ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • Chemistry  (13,620)
  • 2000-2004
  • 1980-1984  (13,620)
  • 1984  (6,762)
  • 1981  (6,858)
  • 1
    facet.materialart.
    Unknown
    American Association for the Advancement of Science (AAAS)
    Publication Date: 1981-08-14
    Description: 〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Klotz, I M -- Haney, D N -- King, L C -- New York, N.Y. -- Science. 1981 Aug 14;213(4509):724-31.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/7256275" target="_blank"〉PubMed〈/a〉
    Keywords: Anemia, Sickle Cell/*drug therapy ; Aspirin/analogs & derivatives/therapeutic use ; Chemical Phenomena ; Chemistry ; *Hemoglobin, Sickle ; Humans ; Protein Binding/drug effects ; Protein Conformation ; Salicylates/*therapeutic use ; Solubility ; Structure-Activity Relationship
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    facet.materialart.
    Unknown
    American Association for the Advancement of Science (AAAS)
    Publication Date: 1984-07-20
    Description: The iron-carbon monoxide stretching mode and the iron-carbon-oxygen bending mode in carbon monoxide-bound cytochrome oxidase have been assigned at 520 and 578 cm-1, respectively. The frequencies, widths, and intensities of these modes show that the Fe-C-O grouping in carbon monoxide-cytochrome a3 is linear but tilted from the normal to the heme plane; that the iron-histidine bond in both five- and six-coordinate cytochrome a3 is strained; and that the carbon monoxide and the proximal histidine each have characteristic, well-defined orientations in all molecules. These data can account for the binding affinities of carbon monoxide and dioxygen under physiological conditions.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Argade, P V -- Ching, Y C -- Rousseau, D L -- New York, N.Y. -- Science. 1984 Jul 20;225(4659):329-31.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/6330890" target="_blank"〉PubMed〈/a〉
    Keywords: Animals ; Carbon Monoxide/metabolism ; Cattle ; Chemical Phenomena ; Chemistry ; Electron Transport Complex IV/*metabolism ; Myoglobin/metabolism ; Oxidation-Reduction ; Oxygen/metabolism ; Spectrum Analysis, Raman
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    facet.materialart.
    Unknown
    American Association for the Advancement of Science (AAAS)
    Publication Date: 1984-01-20
    Description: Peptide synthesis can be used for elucidating the roles of secondary structures in the specificity of hormones, antigens, and toxins. Intermediate sized peptides with these activities assume amphiphilic secondary structures in the presence of membranes. When models are designed to optimize the amphiphilicity of the secondary structure, stronger interactions can be observed with the synthetic peptides than with the naturally occurring analogs.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Kaiser, E T -- Kezdy, F J -- HL-18577/HL/NHLBI NIH HHS/ -- New York, N.Y. -- Science. 1984 Jan 20;223(4633):249-55.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/6322295" target="_blank"〉PubMed〈/a〉
    Keywords: Amino Acid Sequence ; Apolipoprotein A-I ; Apolipoproteins ; Binding Sites ; Calcitonin ; Chemical Phenomena ; Chemistry ; Corticotropin-Releasing Hormone ; Endorphins ; Glucagon ; Growth Hormone-Releasing Hormone ; *Hormones/pharmacology ; Lipoproteins, HDL ; Melitten ; Models, Structural ; *Peptides/chemical synthesis/metabolism/pharmacology ; Protein Conformation ; Structure-Activity Relationship ; beta-Endorphin
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    facet.materialart.
    Unknown
    American Association for the Advancement of Science (AAAS)
    Publication Date: 1984-10-19
    Description: Fourier transform mass spectrometry will play an important role in the future because of its unique combination of high mass resolution, high upper mass limit, and multichannel advantage. These features have already found application in gas chromatography-mass spectrometry, multiphoton ionization, laser desorption, and secondary ion mass spectrometry. However, its most notable feature is the ability to store ions. This characteristic, when combined with the others, will allow expeditious study of the interaction of gas-phase ions with both photons (photodissociation) and neutral molecules, and the convenient application of this fundamental information for chemical analysis.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Gross, M L -- Rempel, D L -- 2-8423576/PHS HHS/ -- New York, N.Y. -- Science. 1984 Oct 19;226(4672):261-8.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/6385250" target="_blank"〉PubMed〈/a〉
    Keywords: Chemical Phenomena ; Chemistry ; *Fourier Analysis ; Ions ; Lasers ; *Mass Spectrometry/instrumentation/methods
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 5
    facet.materialart.
    Unknown
    American Association for the Advancement of Science (AAAS)
    Publication Date: 1984-08-31
    Description: High-resolution carbon-13 nuclear magnetic resonance (NMR) spectra of enzyme-inhibitor and enzyme-substrate complexes provide detailed structural and stereochemical information on the mechanism of enzyme action. The proteases trypsin and papain are shown to form tetrahedrally coordinated complexes and acyl derivatives with a variety of compounds artificially enriched at the site or sites of interest. These results are compared with the structural information derived from x-ray diffraction. Detailed NMR studies have provided a clearer picture of the ionization state of the residues participating in enzyme-catalyzed processes than other more classical techniques. The dynamics of enzymic catalysis can be observed at sub-zero temperatures by a combination of cryoenzymology and carbon-13 NMR spectroscopy. With these powerful techniques, transient, covalently bound intermediates in enzyme-catalyzed reactions can be detected and their structures rigorously assigned.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Mackenzie, N E -- Malthouse, J P -- Scott, A I -- New York, N.Y. -- Science. 1984 Aug 31;225(4665):883-9.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/6433481" target="_blank"〉PubMed〈/a〉
    Keywords: Binding Sites ; Carbon Isotopes ; Carboxypeptidases/metabolism ; Carboxypeptidases A ; Catalysis ; Chemical Phenomena ; Chemistry ; Coenzymes/*metabolism ; Endopeptidases/metabolism ; Enzymes/*metabolism ; Freezing ; Fructose-Bisphosphate Aldolase/metabolism ; Magnetic Resonance Spectroscopy ; Papain/metabolism ; Pepsin A/metabolism ; Peptide Hydrolases/*metabolism ; Protease Inhibitors ; Pterins/metabolism ; Pyridoxal Phosphate/metabolism ; Serine Endopeptidases
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 6
    facet.materialart.
    Unknown
    American Association for the Advancement of Science (AAAS)
    Publication Date: 1984-03-09
    Description: 〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Maugh, T H 2nd -- New York, N.Y. -- Science. 1984 Mar 9;223(4640):1051-2.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/6695193" target="_blank"〉PubMed〈/a〉
    Keywords: *Air Pollutants ; *Atmosphere ; Carbon Tetrachloride ; Chemical Phenomena ; Chemistry ; *Chlorofluorocarbons, Methane ; Free Radicals ; Nitrogen Dioxide ; Nitrous Oxide ; Oxygen ; *Ozone ; Photochemistry ; Risk ; Singlet Oxygen ; Trichloroethanes ; Ultraviolet Rays
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 7
    Publication Date: 1984-10-19
    Description: Pyrolysis mass spectrometry in combination with computerized multivariate statistical analysis enables qualitative and quantitative analysis of nonvolatile organic materials containing molecular assemblies of a complexity and size far beyond the capabilities of direct mass spectrometry. The state of the art in pyrolysis mass spectrometry techniques is illustrated through specific applications, including structural determination and quality control of synthetic polymers, quantitative analysis of polymer mixtures, classification and structural characterization of fossil organic matter, and nonsupervised numerical extraction of component patterns from complex biological samples.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Meuzelaar, H L -- Windig, W -- Harper, A M -- Huff, S M -- McClennen, W H -- Richards, J M -- New York, N.Y. -- Science. 1984 Oct 19;226(4672):268-74.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/6484572" target="_blank"〉PubMed〈/a〉
    Keywords: Biochemical Phenomena ; Biochemistry ; Chemical Phenomena ; Chemistry ; Coal ; Enterobacteriaceae/analysis/isolation & purification ; Hot Temperature ; Mass Spectrometry/*methods ; Polymers
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 8
    Publication Date: 1984-08-31
    Description: The splicing of messenger RNA precursors in vitro proceeds through an intermediate that has the 5' end of the intervening sequence joined to a site near the 3' splice site. This lariat structure, which has been characterized for an adenovirus 2 major late transcript, has a branch point, with 2'-5' and 3'-5' phosphodiester bonds emanating from a single adenosine residue. The excised intervening sequence retains the branch site and terminates in a guanosine residue with a 3' hydroxyl group. The phosphate group at the splice junction between the two exons originates from the 3' splice site at the precursor.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Padgett, R A -- Konarska, M M -- Grabowski, P J -- Hardy, S F -- Sharp, P A -- P01-CA14051/CA/NCI NIH HHS/ -- P01-CA26717/CA/NCI NIH HHS/ -- R01-GM32467/GM/NIGMS NIH HHS/ -- New York, N.Y. -- Science. 1984 Aug 31;225(4665):898-903.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/6206566" target="_blank"〉PubMed〈/a〉
    Keywords: Adenoviruses, Human/metabolism ; Base Sequence ; Chemical Phenomena ; Chemistry ; Nucleic Acid Conformation ; Nucleic Acid Precursors/analysis/*metabolism ; Oligoribonucleotides/metabolism ; Phosphates/metabolism ; RNA/analysis/*metabolism ; RNA Precursors ; *RNA Splicing ; RNA, Messenger/analysis/*metabolism ; RNA, Viral/analysis/*metabolism
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 9
    facet.materialart.
    Unknown
    American Association for the Advancement of Science (AAAS)
    Publication Date: 1984-05-11
    Description: The mechanism of lipid peroxidation and the manner in which antioxidants function is reviewed. beta-Carotene is a purported anticancer agent, which is believed by some to have antioxidant action of a radical-trapping type. However, definitive experimental support for such action has been lacking. New experiments in vitro show that beta-carotene belongs to a previously unknown class of biological antioxidants. Specifically, it exhibits good radical-trapping antioxidant behavior only at partial pressures of oxygen significantly less than 150 torr, the pressure of oxygen in normal air. Such low oxygen partial pressures are found in most tissues under physiological conditions. At higher oxygen pressures, beta-carotene loses its antioxidant activity and shows an autocatalytic, prooxidant effect, particularly at relatively high concentrations. Similar oxygen-pressure-dependent behavior may be shown by other compounds containing many conjugated double bonds.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Burton, G W -- Ingold, K U -- New York, N.Y. -- Science. 1984 May 11;224(4649):569-73.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/6710156" target="_blank"〉PubMed〈/a〉
    Keywords: Antioxidants/*metabolism ; Carotenoids/*metabolism ; Chemical Phenomena ; Chemistry ; Free Radicals ; Humans ; Linoleic Acids/metabolism ; *Lipid Metabolism ; Oxidation-Reduction ; Oxygen/metabolism ; Partial Pressure ; Peroxides/metabolism ; Tetrahydronaphthalenes/metabolism ; beta Carotene
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 10
    facet.materialart.
    Unknown
    American Association for the Advancement of Science (AAAS)
    Publication Date: 1984-03-16
    Description: Yeast phenylalanine transfer RNA was subjected to a 12-picosecond molecular dynamics simulation. The principal features of the x-ray crystallographic analysis are reproduced, and the amplitudes of atomic displacements appear to be determined by the degree of exposure of the atoms. An analysis of the hydrogen bonds shows a correlation between the average length of a bond and the fluctuation in that length and reveals a rocking motion of bases in Watson-Crick guanine X cytosine base pairs. The in-plane motions of the bases are generally of larger amplitude than the out-of-plane motions, and there are correlations in the motions of adjacent bases.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Harvey, S C -- Prabhakaran, M -- Mao, B -- McCammon, J A -- New York, N.Y. -- Science. 1984 Mar 16;223(4641):1189-91.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/6560785" target="_blank"〉PubMed〈/a〉
    Keywords: Chemical Phenomena ; Chemistry ; Computers ; Cytosine ; Guanine ; Hydrogen Bonding ; Nucleic Acid Conformation ; *RNA, Fungal ; *RNA, Transfer, Amino Acyl ; Yeasts/analysis
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 11
    Publication Date: 1984-11-16
    Description: Sequence-dependent variations in DNA revealed by x-ray crystallographic studies have suggested that certain DNA-reactive drugs may react preferentially with defined sequences in DNA. Drugs that wind around the helix and reside within one of the grooves of DNA have perhaps the greatest chance of recognizing sequence-dependent features of DNA. The antitumor antibiotic CC-1065 covalently binds through N-3 of adenine and resides within the minor groove of DNA. This drug overlaps with five base pairs for which a high sequence specificity exists.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Hurley, L H -- Reynolds, V L -- Swenson, D H -- Petzold, G L -- Scahill, T A -- New York, N.Y. -- Science. 1984 Nov 16;226(4676):843-4.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/6494915" target="_blank"〉PubMed〈/a〉
    Keywords: Antibiotics, Antineoplastic/*metabolism ; *Base Sequence ; Binding Sites ; Chemical Phenomena ; Chemistry ; DNA/*metabolism ; *Indoles ; Leucomycins/*metabolism ; Molecular Conformation ; X-Ray Diffraction
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 12
    Publication Date: 1984-06-15
    Description: A new class of synthetic antifungal agents, the allylamines , has been developed by modification of naftifine , a topical antimycotic. SF 86-327, the most effective of these compounds so far, is highly active in vitro against a wide range of fungi and exceeds clinical standards in the oral and topical treatment of guinea pig dermatophytoses. SF 86-327 is a powerful specific inhibitor of fungal squalene epoxidase, a key enzyme in sterol biosynthesis.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Petranyi, G -- Ryder, N S -- Stutz, A -- New York, N.Y. -- Science. 1984 Jun 15;224(4654):1239-41.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/6547247" target="_blank"〉PubMed〈/a〉
    Keywords: Allylamine/analogs & derivatives/*chemical synthesis/pharmacology ; Amines/*chemical synthesis ; Animals ; Antifungal Agents/*chemical synthesis/pharmacology ; Chemical Phenomena ; Chemistry ; Dermatomycoses/drug therapy ; Fungi/*drug effects/enzymology ; Guinea Pigs ; Naphthalenes/chemical synthesis/pharmacology ; Oxygenases/*antagonists & inhibitors ; Squalene Monooxygenase
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 13
    Publication Date: 1984-11-02
    Description: By recombinant DNA techniques, a disulfide bond was introduced at a specific site in T4 lysozyme, a disulfide-free enzyme. This derivative retained full enzymatic activity and was more stable toward thermal inactivation than the wild-type protein. The derivative, T4 lysozyme (Ile3----Cys), was prepared by substituting a Cys codon for an Ile codon at position 3 in the cloned lysozyme gene by means of oligonucleotide-dependent, site-directed mutagenesis. The new gene was expressed in Escherichia coli under control of the (trp-lac) hybrid tac promoter, and the protein was purified. Mild oxidation generated a disulfide bond between the new Cys3 and Cys97, one of the two unpaired cysteines of the native molecule. Oxidized T4 lysozyme (Ile3----Cys) exhibited specific activity identical to that of the wild-type enzyme when measured at 20 degrees C in a cell-clearing assay. The cross-linked protein was more stable than the wild type during incubation at elevated temperatures as determined by recovered enzymatic activity at 20 degrees C.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Perry, L J -- Wetzel, R -- New York, N.Y. -- Science. 1984 Nov 2;226(4674):555-7.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/6387910" target="_blank"〉PubMed〈/a〉
    Keywords: Chemical Phenomena ; Chemistry ; DNA, Recombinant/metabolism ; Escherichia coli/enzymology ; *Genetic Engineering ; Kinetics ; Muramidase/*genetics/metabolism ; Protein Denaturation
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 14
    facet.materialart.
    Unknown
    American Association for the Advancement of Science (AAAS)
    Publication Date: 1984-06-08
    Description: The effect of a partial pressure of nitrogen of 50 atmospheres (5065 kilopascals ) on the hydrogen evolution reaction of nitrogenase has been investigated. Evolution of hydrogen was not blocked completely by 50 atmospheres of nitrogen in any of four experiments; rather, 27.3 +/- 2.4 percent of the total electron flux through nitrogenase was directed toward production of hydrogen. The ratio of hydrogen evolved to nitrogen fixed was close to 1:1, which implies that hydrogen evolution is obligatory in the fixation of molecular nitrogen by nitrogenase.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Simpson, F B -- Burris, R H -- AI-00848/AI/NIAID NIH HHS/ -- New York, N.Y. -- Science. 1984 Jun 8;224(4653):1095-7.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/6585956" target="_blank"〉PubMed〈/a〉
    Keywords: Chemical Phenomena ; Chemistry ; *Hydrogen ; *Nitrogen ; Nitrogen Fixation ; *Nitrogenase ; Partial Pressure
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 15
    Publication Date: 1981-10-16
    Description: The DNA/RNA Synthesizer provides a complete and automated procedure for the synthesis of DNA sequences. Each base unit is added in a 30-minute cycle, permitting a tetradecamer to be constructed in 6 1/2 hours. The complete procedure is described, including a practical procedure for isolation and purification of the desired DNA sequence.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Alvarado-Urbina, G -- Sathe, G M -- Liu, W C -- Gillen, M F -- Duck, P D -- Bender, R -- Ogilvie, K K -- New York, N.Y. -- Science. 1981 Oct 16;214(4518):270-4.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/6169150" target="_blank"〉PubMed〈/a〉
    Keywords: Automation ; Chemical Phenomena ; Chemistry ; DNA/*chemical synthesis ; *Genes, Synthetic ; RNA/*chemical synthesis ; Solubility
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 16
    facet.materialart.
    Unknown
    American Association for the Advancement of Science (AAAS)
    Publication Date: 1981-05-15
    Description: Research on chitin as a marine resource is pointing to novel applications for this cellulose-like biopolymer. Discovery of nondegrading solvent systems has permitted the spinning of filaments, for example, for use as surgical sutures. New methods for preparing the bioactive alkyl glycoside of N-acetyl-D-glucosamine (the monomer unit of chitin) and a microcrystalline chitin has encouraged their use as promoters for growth of bifidobacteria and as an aid in digestion of high-lactose cheese whey by domestic animals. Chitin-protein complexes of several crustacean species show great variability in ratios of chitin to covalently bound protein and in residual protein in the "purified" chitins.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Austin, P R -- Brine, C J -- Castle, J E -- Zikakis, J P -- New York, N.Y. -- Science. 1981 May 15;212(4496):749-53.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/7221561" target="_blank"〉PubMed〈/a〉
    Keywords: Animal Feed ; Animals ; Cheese ; Chemical Phenomena ; Chemistry ; Chickens ; *Chitin ; Crystallography ; Lactose/metabolism ; Proteins/analysis ; Sutures ; *Technology
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 17
    facet.materialart.
    Unknown
    American Association for the Advancement of Science (AAAS)
    Publication Date: 1981-12-18
    Description: 〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Gilbert, W -- New York, N.Y. -- Science. 1981 Dec 18;214(4527):1305-12.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/7313687" target="_blank"〉PubMed〈/a〉
    Keywords: Base Sequence ; Chemical Phenomena ; Chemistry ; DNA/*genetics ; Eukaryotic Cells/physiology ; *Genes ; Hydrazines ; Lac Operon ; Methylation ; Prokaryotic Cells/physiology ; Sulfuric Acid Esters
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 18
    facet.materialart.
    Unknown
    American Association for the Advancement of Science (AAAS)
    Publication Date: 1981-12-11
    Description: The scrapie agent causes a degenerative nervous system disease in sheep and goats. Studies with extensively purified preparations demonstrated that the agent contains a protein that is required for infectivity. Chemical modification of the scrapie agent by diethyl pyrocarbonate reduced the titer 1000-fold. Exposure of the inactivated agent to hydroxylamine, a strong nucleophile, resulted in complete restoration of infectivity. Presumably, nucleophilic residues within a scrapie agent protein undergo carbethoxylation on reaction with diethyl pyrocarbonate, and subsequent addition of hydroxylamine displaces these carbethoxy groups.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉McKinley, M P -- Masiarz, F R -- Prusiner, S B -- NS14069/NS/NINDS NIH HHS/ -- New York, N.Y. -- Science. 1981 Dec 11;214(4526):1259-61.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/6795721" target="_blank"〉PubMed〈/a〉
    Keywords: Animals ; Biological Assay ; Brain/microbiology ; Chemical Phenomena ; Chemistry ; Cricetinae ; Diethyl Pyrocarbonate/pharmacology ; Histidine/pharmacology ; *Prions ; Ribonucleases/pharmacology ; Serum Albumin, Bovine/pharmacology ; Viral Proteins/*isolation & purification/pharmacology
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 19
    facet.materialart.
    Unknown
    American Association for the Advancement of Science (AAAS)
    Publication Date: 1981-01-30
    Description: The incubation of lens proteins with reducing sugars leads to the formation of fluorescent yellow pigments and cross-like similar to those reported in aging and cataractous human lenses. Called nonenzymatic browning or the Maillard reaction, this aging process also occurs in stored foods. Reducing sugars condense with the free amino group of proteins, then rearrange and dehydrate to form unsaturated pigments and cross-linked products. Although most proteins in living systems turn over with sufficient rapidity to avoid nonenzymatic browning, some, such as lens crystallins and skin collagen, are exceptionally long-lived and may be vulnerable.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Monnier, V M -- Cerami, A -- AM 19655/AM/NIADDK NIH HHS/ -- New York, N.Y. -- Science. 1981 Jan 30;211(4481):491-3.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/6779377" target="_blank"〉PubMed〈/a〉
    Keywords: *Aging ; Animals ; Cattle ; Chemical Phenomena ; Chemistry ; *Crystallins ; Diabetes Mellitus/physiopathology ; Glucose ; Glucosephosphates ; In Vitro Techniques ; Lysine ; *Proteins ; Spectrophotometry, Ultraviolet
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 20
    facet.materialart.
    Unknown
    American Association for the Advancement of Science (AAAS)
    Publication Date: 1981-03-13
    Description: Great advances have been made in fundamental scientific research in recent years. The new knowledge gathered, in addition to deepening our understanding of the physical universe, contributes a range of abilities and opportunities to society that would not otherwise be available. Much research that may be called applied because it addresses needs of society is quite fundamental in character, and support of such research at the National Science Foundation is to be handled in tandem by the research directorates. Other areas that require a refocusing of support are engineering science and education, at all levels, in science and engineering. Increasing our strength in these areas is essential to achieve our national economic, social, and political goals. Steps are being taken by the National Science Foundation to make its structure better able to deal with engineering and applied research and to provide greater mutual reinforcement between applied and basic research.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Slaughter, J B -- New York, N.Y. -- Science. 1981 Mar 13;211(4487):1131-6.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/7466384" target="_blank"〉PubMed〈/a〉
    Keywords: Cell Biology ; Chemical Phenomena ; Chemistry ; *Forecasting ; Geological Phenomena ; Geology ; *Government Agencies ; Molecular Biology ; Neurochemistry ; Physical Phenomena ; Physics ; Research Support as Topic ; United States
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 21
    Publication Date: 1984-05-25
    Description: Polypeptide analogs of the known members of the corticotropin-releasing factor (CRF) family were synthesized and tested in vitro and in vivo for enhanced potency or competitive antagonism. Predictive methods and physicochemical measurements had suggested an internal secondary alpha-helical conformation spanning about 25 residues for at least three members of the CRF family. Maximization of alpha-helix-forming potential by amino acid substitutions from the native known sequences (rat/human and ovine CRF, sauvagine, and carp and sucker urotensin 1) led to the synthesis of an analog that was found to be more than twice as potent as either of the parent peptides in vitro. In contrast, certain amino-terminally shortened fragments, such as alpha-helical CRF or ovine CRF residues 8 to 41, 9 to 41, and 10 to 41, were found to be competitive inhibitors in vitro. Selected antagonists were examined and also found to be active in vivo.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Rivier, J -- Rivier, C -- Vale, W -- AA03504/AA/NIAAA NIH HHS/ -- AM20917/AM/NIADDK NIH HHS/ -- AM26741/AM/NIADDK NIH HHS/ -- etc. -- New York, N.Y. -- Science. 1984 May 25;224(4651):889-91.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/6326264" target="_blank"〉PubMed〈/a〉
    Keywords: Adrenocorticotropic Hormone/secretion ; Animals ; Binding, Competitive ; Chemical Phenomena ; Chemistry ; Corticotropin-Releasing Hormone/*antagonists & inhibitors ; Rats
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 22
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Materialwissenschaft und Werkstofftechnik 12 (1981), S. A2 
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 23
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Materialwissenschaft und Werkstofftechnik 12 (1981), S. 11-13 
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Description / Table of Contents: Quality Control of HDPE Pipes.Trials are reported made with the aim of finding an correlation between creep rupture test results obtained with two different types of testing samples: Pipes under internal pressure and tensile rods cut out of these pipes in a longitudinal direction.
    Notes: Es wird über Versuche berichtet, eine Korrelation zwischen Ergebnissen aus Zeitstand-Innendruckversuchen an HDPE-Rohren und Zeitstandversuchen an Längszugstäben aus diesen Rohren zu finden.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 24
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Materialwissenschaft und Werkstofftechnik 12 (1981), S. 23-31 
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Description / Table of Contents: Controlled Pickling of Apparatus made of Chemical-Resistant SteelsExamples of material failure and corrosion trials are used to show that the chemical resistance of austenitic steel depends in many ways on the surface condition. Pickling is the best method for removing layers of oxide in preparation for passivation. Internal tensile stresses which are created near the surface by mechanical working, e.g. by turning, drilling and grinding, can assume higher values than those caused by shaping and welding. As a result stress corrosion cracking often occurs only in the region where the surface has been worked. Because the stresses responsible for this phenomenon rapidly fall off below the surface, it is usually possible to reduce them by pickling to the point at which damage of this kind is prevented. The amount of material which must be removed by pickling is determined by trials and pickling must be controlled accordingly.
    Notes: An Schadensfällen und durch Korrosionsversuche wird gezeigt, daß die chemische Beständigkeit der austenitischen Stähle in mehrfacher Weise von ihrem Oberflächenzustand abhängt. Beim Entfernen von Oxidbelägen, als Voraussetzung für eine gute Passivschicht, liefert das Beizen das beste Ergebnis. Oberflächennahe Zug-Eigenspannungen, die durch eine mechanische Bearbeitung, z. B. Drehen, Bohren, Schleifen, eingebracht werden, können höhere Werte annehmen als die durch Verformen und Schweißen verursachten Spannungen. Als Folge davon tritt oft nur im Bereich einer Oberflächenbearbeitung Spannungsrißkorrosion auf. Weil die zugehörigen Spannungen unter der Oberfläche schnell abfallen, ist es meist möglich, sie durch ein abtragendes Beizen so weit abzubauen, daß Schäden dieser Art unterbleiben. Der notwendige Beizabtrag ist durch Versuche zu ermitteln und das Beizen entsprechend zu überwachen.
    Additional Material: 16 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 25
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Materialwissenschaft und Werkstofftechnik 12 (1981), S. 90-96 
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Description / Table of Contents: Crack Growth Behaviour of Structural Steels in SeawaterThe influence of a synthetic seawater environment upon the crack growth behaviour of two structural steels was investigated. The results were presented in terms of the stress intensity fracture toughness parameter. Data were generated in air and in seawater with or without a cathodic protection. Results show that seawater environment and a cathodic protection influence the crack propagation at the applied frequencies of 0,04 and 0,25 Hz. The use of cathodic protection raises questions concerning the resistance to hydrogen embrittlement of the two steels. Some fractographic examinations of selected specimens show the microstructure of the two steels at various test conditions.
    Notes: Die Kenntnis der Ausbreitungsgeschwindigkeit von Rissen an Materialien in korrosiver Atmosphäre unter Betriebsbelastung ist für die Konstruktionsauslegung von großer Bedeutung. Von den Baustählen X70 sowie St70 ist mittels angeschwungener CT-Proben die Rißausbreitung bestimmt worden. Die Versuchsfrequenzen lagen - bezogen auf realistische Seegangsspektren - bei 0,04 Hz und 0,25 Hz. Durch Aufgabe kathodischer Schutzpotentiale wird bei Vorhandensein von Anrissen die Rißausbreitung stark beschleunigt. Es tritt eine wasserstoffinduzierte Spannungsrißkorrosion auf. Über das Ausmaß der Wasserstoffaufname der Bruchflächen werden Angaben gemacht. Durch REM-Aufnahmen wird das Bruchaussehen dokumentiert.
    Additional Material: 15 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 26
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Materialwissenschaft und Werkstofftechnik 12 (1981), S. 107-108 
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 27
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Materialwissenschaft und Werkstofftechnik 12 (1981), S. A28 
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 28
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Materialwissenschaft und Werkstofftechnik 12 (1981), S. 19-22 
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Description / Table of Contents: Investigation of Different Welding Processes with Nickel-Alloy NiMo 16 Cr 16 TIThe overall favourable corrosion resistance of the nickel-chromium-molybdenum alloy NiMo 16Cr 16 Ti against attack by powerful oxidizing acids ensures a wide field of applications for this material. The alloy is readily processable using encased rod electrodes and shielded are welding. However, shielded arc welding should be given preference, as there are considerable differences in the analytical results between smelted welded material from encased rod electrodes and bright rods and wires. The different welded materials influence the corrosion resistance and the possibilities of forging welded constructions.
    Notes: Die allgemeine gute Korrosionsbeständigkeit der Nickelbasislegierung NiMo 16 Cr 16 Ti gegen den Angriff stark oxidierender Säuren sichert diesem Werkstoff ein breites Einsatzgebiet. Die Legierung ist mit umhüllten Stabelektroden und nach Schutzgasschweißverfahren gut zu verarbeiten. Bevorzugt sollte jedoch das Schutzgasschweißen eingesetzt werden, da erhebliche Analyseunterschiede zwischen dem niedergeschmolzenen Schweißgut aus umhüllten Stabelektroden und aus blanken Stäben und Drähten bestehen. Das unterschiedliche Schweißgut hat Einfluß auf das Korrosionsverhalten und die Warmformgebungsmöglichkeiten von geschweißten Konstruktionen.
    Additional Material: 11 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 29
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Materialwissenschaft und Werkstofftechnik 12 (1981), S. A10 
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 30
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Materialwissenschaft und Werkstofftechnik 12 (1981), S. 150-150 
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 31
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Materialwissenschaft und Werkstofftechnik 12 (1981), S. A34 
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 32
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Materialwissenschaft und Werkstofftechnik 12 (1981), S. 256-262 
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Description / Table of Contents: Anisotropy Effects in Copper Alloy Strip MaterialsThe textures and effects of mechanical anisotropy have been measured in several copper alloy strip materials with commercial hardness levels. In most cases mixed textures have been found with a qualitative correlation to the mechanical effects.The optimum position for spring elements proved to be transverse to rolling direction, especially the relation of the elastic limit in bonding to yield strength has a maximum in this direction.
    Notes: Bei Bändern aus verschiedenen Kupferlegierungen in handelsüblichen Festigkeitszuständen wurden die Texturen und die mechanischen Anisotropieeffekte gemessen. In den meisten Fällen wurden Mischtexturen festgestellt, welche die mechanischen Anisotropieeffekte qualitativ erklären.Für Federelemente ist die Querlage die günstigste, insbesondere ist in dieser Richtung das Verhältnis Federbiegegrenze zu Streckgrenze am höchsten.
    Additional Material: 10 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 33
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Materialwissenschaft und Werkstofftechnik 12 (1981) 
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 34
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Materialwissenschaft und Werkstofftechnik 12 (1981), S. 330-334 
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Description / Table of Contents: The Guarantee of Quality for the Steel Hoops of the Refueling Machine of the Nuclear Ship OTTO HAHN by Way of a Special Procedure with UltrasonicThe basic overhaul and renewal of the refueling machine constructed 1965-1967 for the reactor system of the nuclear ship OTTO HAHN required among other things the replacement of the lifting hoops which are necessary for raising the fuel elements and guiding the gripping device. These steel hoops are the critical components of the refueling machine. Therefore the quality assurance of the material was articularly specified.On way of ensuring this guarantee of quality is to carry out tests involving the use of ultrasonic equipment as desired and applied here. The process is explained and its application with the results obtained is described.
    Notes: Die Grundüberholung und teilweise Erneuerung der in den Jahren 1965-1967 gebauten Brennelement-Wechselmaschine für die Reaktoranalage des NS OTTO HAHN erforderte u.a. die Auswechselung der zur Lastaufnahme und Greifersteuerung dienenden Hubbänder. Diese Stahlbänder sind die kritischen Bauteile der Brennelement-Wechselmaschine. Aus diesem Grunde wurde die Gütesicherung besonders spezifiert. Eine der Gütesicherung dienende zerstörungsfreie Prüfung ist die hier beschriebene und angewendete Impuls-Durchschallung in Tauchtechnik. Das Verfahren wird erklärt und die Durchführung mit dem erzielten Ergebnis beschrieben.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 35
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Materialwissenschaft und Werkstofftechnik 12 (1981), S. 315-324 
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Description / Table of Contents: Behaviour of Hip - Joint Endoprostheses under quasi-static and dynamic LoadClinical experience with total-hip endoprostheses has shown that the following problems take priority: - Loosening of the socket (acetabular cup) and the femoral prosthesis - Fracture of the femoral prosthesis - Loosing due to deep infection.Accordingly aims the research at locating the biological and mechanical reasons for the failures as well as testing alternative solutions such as - methods of fixation - construction of protheses - new materials and finishing methods. This publication concerns areas of the mechanical side of the problem.The comparison between the original system of proximal femur and acetabulum and the implanted prosthetic system shows changes in the stiffness of the systems depending on the different types of implanted endoprostheses.The influence of the frequency of loading on the deformation of the system is investigated in a frequency range between quasi-static and dynamically changing loads.The movements between implanted cup and neighbouring pelvic bone during cyclic load is measured.The results of these examinations give clues concerning qualitative and quantitative repercussions from the different endoprosthetic systems under conditions optimal in view of true comparison, and possible or desirable alternative solutions of the problem in view of construction and material.
    Notes: Aufgrund bisher vorliegender klinischer Erfahrungen mit Hüftgelenks-Totalendoprothesen nehmen folgende Problemstellungen eine gewisse Priorität ein: - Pfannen- und Schaftlockerungen, - Schaftbrüche - Infektlockerungen.Dementsprechend konzentriert sich die Forschung auf die Ermittlung der biologischen und mechanischen Ursachen des Fehlverhaltens sowie auf die Erprobung alternativer Lösungen hinsichtlich - Fixationsmethodik - Konstruktion von Endoprothesen - Werkstoff und Fertigungsmethoden.Die vorliegende Arbeit bezieht sich auf Teile des mechanischen Komplexes dieser Problemstellung.Durch vergleichende Untersuchungen am Original- sowie am Implantatsystem „proximaler Femur/Hüftgelenkspfanne“ wird die Änderung der Steifigkeit infolge Implantation unterschiedlicher Typen von Endoprothesen ermittelt.Der Einfluß der Belastungsfrequenz auf die Deformationsverhältnisse in diesem System wird in einem Frequenzbereich überprüft, der sich von quasi-statischer bis zu dynamisch-wechselnder Belastung erstreckt.Die Relativbewegung zwischen implantierter Hüftgelenkspfanne und benachbartem knöchernen Bereich wird bei zyklischer Belastung erfaßt und messend verfolgt.Die Befunde geben punktuelle Hinweise hinsichtlich qualitativer und quantitativer Auswirkungen unterschiedlicher endoprothetischer Maßnahmen unter Bedingungen optimierter Vergleichbarkeit sowie hinsichtlich möglicher oder zweckmäßiger alternativer Lösungen im konstruktiven und stofflichen Bereich der anstehenden Fragestellungen.
    Additional Material: 15 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 36
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Materialwissenschaft und Werkstofftechnik 12 (1981), S. A76 
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 37
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Materialwissenschaft und Werkstofftechnik 12 (1981), S. 335-335 
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 38
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Materialwissenschaft und Werkstofftechnik 12 (1981), S. 366-374 
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Description / Table of Contents: Exact and Approximate Calculations of UD-LayersIt is shown that the quasi-elastic solution of layers nearly almost used in practical viscoelastic calculations is an excellent approach. The exact solution achieved with simple integral equations are compared with the quasi-elastic solution and the occuring deviations are described. The creep functions of layers are given the form of the uniaxial creep function of the isotropic viscoelastic material. This makes the creep behaviour of layers very clear and symplifies practical calculations. The given solutions are under no restriction with regard to the chosen form of the uni-axial creep function.
    Notes: Es wird gezeigt, daß die in der Praxis zur viskoelastischen Berechnung unidirektionaler Laminate verwendete quasielastische Lösung eine hervorragende Näherungslösung darstellt. Die exakten, mit Hilfe einfacher Integralbeziehungen gewonnenen, Lösungen werden mit der quasielastischen Lösung verglichen und es werden die zu erwartenden Abweichungen beschrieben. Die Kriechfunktionen der Laminate werden auf die Form der Kriechfunktion des viskoelastisch-isotropen Materials bei einachsiger Beanspruchung gebracht. Dadurch wird das Kriechverhalten der Laminate besonders deutlich und die praktische Rechnung wird vereinfacht. Die bereitgestellten Lösungen unterliegen keiner Beschränkungen hinsichtlich der funktionalen Form der einachsigen Kriechfunktion.
    Additional Material: 12 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 39
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Materialwissenschaft und Werkstofftechnik 12 (1981), S. 402-407 
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Description / Table of Contents: Pitting Corrosion at Copper Tubes of Tap Water Systems released by Soldering FluxThe pitting corrosion is the mostly observed reason for getting corrosion damage of copper tubes in tap water systems. In case of loss the reason for corrosion attack is ascribed to rests of cracked drawing compounds at the copper tube wall.The results from own examinations of copper tubes corroded in different tap waters show in case of loss the reason for corrosion damage as cracked soldering flux. This gets by the different described ways into the copper tube and becomes cracked by the soldering temperature. This way formed corrosion attacks often show breaches firstly far away from the soldered joint so that mostly other reasons of damage (cracked drawing compounds) are simulated.
    Notes: Die häufigste zum Versagen von Kupferrohren in der Trinkwasserinstallation führende Korrosionsart ist die Lochkorrosion. Als schadensauslösend werden dabei in der Literatur die beim Weichglühen der Rohre gecrackten Ziehmittelreste (Kohlenstoffbeläge der Rohrinnenwandungen) und Rückstände von chloridhaltigen Weichlöt-Fluß-mitteln angesehen.Eigene Untersuchungen von Schadensfällen an Kupferrohren der Trinkwasserinstallation zeigen, daß die Ursache, welche zum Versagen der Rohre führt, meistens nicht gecrackte Ziehmittelreste oder eingeflossenes Flußmittel, sondern gecrackte Flußmittel sind. Diese gelangen, auf unterschiedlichste Art und Weise, in das Rohrinnere und werden beim Einwirken der Löttemperatur gecrackt. Da ein so eingeleiteter Korrosionsangriff oftmals erst in relativ weiter Entfernung von der Lötstelle zum Durchbruch führt (Kondensatzone), werden meist andere Schadensursachen (z. B. gecrackte Ziehmittelreste) vorgetäuscht.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 40
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Materialwissenschaft und Werkstofftechnik 12 (1981), S. 438-439 
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 41
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 42
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Materialwissenschaft und Werkstofftechnik 15 (1984), S. 49-58 
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Description / Table of Contents: Fundamentals of Material Selection in the Conditions of Erosive WearProblems of proper selection of materials for parts subjected to wear by a stream of abrasive particles are discussed. Considering the main laws governing such kind of wear, the author concludes that target material selection in the case of erosion, like in any other case of abrasive wear, will depend on the ratio of abrasive grain hardness to material hardness. Special attention should be given to hard components in the abrasive. It has been established that a 10-15% content of quartz particles in the abrasive is enough to cause an abrupt fall in the wear resistance of chilled steels, white iron and hard surfacing alloys, thus making their use questionable. Finegrained WC-Co-type sintered carbides have shown the highest wear resistance in such conditions.The conclusions drawn in this paper are borne cut by a considerable body of experimental data.
    Notes: In dem Artikel werden Probleme der zweckmäßigen Werkstoffauswahl bei der Strahlverschleißbekämpfung behandelt, die allgemeinen Gesetzmäßigkeiten deser Verschleißart dargelegt und gezeigt, daß analog zu anderen Abrasivverschleißarten auch in diesem Fall die Materialauswahl durch einen Vergleich von Werkstoff- und Schleifkornhärte erleichtert wird. Besondere Aufmerksamkeit gilt dem Einfluß von Zusätzen harter Körner in Strahlmittel. Schon ein etwa 10-15prozentiger Anteil von Quarzteilchen ruft eine jähe Senkung des relativen Verschleißwiderstandes bei gehärteten Stählen, Hartguß und Auftragsschweißwiderstandes bei gehärteten Stählen, Hartguß und Auftragsschweißungen hervor und macht deren Anwendung problematisch. Den größten Verschleißwiderstand unter solchen Bedingungen haben feinkörniger WC-Co-Sinterhartmetalle.Die Schlußfolgerungen werden durch umfangreiche Versuchsergebnisse belegt.
    Additional Material: 12 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 43
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Materialwissenschaft und Werkstofftechnik 15 (1984), S. 95-96 
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Description / Table of Contents: A Study on Alloy Element Loss in MIG Welding of Stainless SteelsAAS-analysis of welding fume yields information about alloy element loss in MIG welding of stainless steels. Welding under shielding gases short of oxygen, the heavy metal loss can be correlated with the element's partial pressures in the welding wire alloy.
    Notes: Durch Analyse des Schweißrauches läßt sich Aufschluß über das Abbrandverhalten von Drahtelektroden gewinnen. Beim MAG-Schweißen unter sauerstoffarmen Schutzgasen wird der Schwermetall-Abbrand durch die Partialdrucke der Legierungskomponenten kontrolliert.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 44
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Materialwissenschaft und Werkstofftechnik 15 (1984), S. 102-107 
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Additional Material: 11 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 45
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 46
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Materialwissenschaft und Werkstofftechnik 12 (1981), S. 14-18 
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Description / Table of Contents: Creep Behaviour of Steel × 10 NiCrATi 32 20 at Elevated Temperatures and Over Long Periods.The demands made on the quality of materials for chemical plants are continually increasing. Not only has there been a changeover to large units and an increase in the pressures and temperatures employed, but for technical and financial reasons the properties of the materials must be optimally utilized. In components subjected to the highest stresses due to pressure and temperature, the service life has to be calculated with the aid of creep strength characteristics. On the basis of the austenitic material × 10NiCrAlTi 32 20 an attempt is made, with the aid of creep strength characteristics, which have been determined in our own long-time test, to make a statement regarding the structural states existing at defined times and to draw conclusions for the use of this material.
    Notes: Die Ansprüche an die Leistungsfähigkeit der Werkstoffe für Chemieanlagen wachsen ständig. So ist neben dem Übergang zu großen Einheiten nicht nur ein Ansteigen der Drücke und Temperaturen zu verzeichnen, sondern aus technischen und wirtschaftlichen Gründen auch ein optimale Ausnutzung der Werkstoffeigenschaften. Bei den durch Druck und Temperatur höchstbeanspruchten Bauteilen muß die Lebensdauer anhand von Zeitstandfestigkeitskennwerten berechnet werden.An dem austenitischen Werkstoff × 10 NiCrAlTi 32 20 wird versucht, anhand von Zeitstandfestigkeitsuntersuchungen, die im eigenen Langzeitversuch ermittelt sind, eine Aussage über die zeitabhängige Gefügeausbildung zu machen und daraus Schlüsse für den Einsatz dieses Werkstoffes zu ziehen.
    Additional Material: 13 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 47
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Materialwissenschaft und Werkstofftechnik 12 (1981), S. A7 
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 48
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Materialwissenschaft und Werkstofftechnik 12 (1981), S. 33-39 
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Description / Table of Contents: Parametric Analysis of Creep Tests under Pressur and Kind of Failure in Thermoplastic Tubes under Chemical LoadCreep tests under pressure are a method to evaluate the long term behaviour of tubes under mechanical, thermic and chemical loading. However, this method does not enclude essential criteria of failure. In form of a parametric analysis this paper proves that “weeping” takes place much earlier than total failure by rupture.Investigations on the different kinds of damage within the tube material using light microscopy and electron scanning microscopy reveal- that it is not correct to transform results of creep tests with small and thin tubes to such of practically used dimensions. This is on the one hand based on the existance of different microstructures which are specific to the semicristalline material and on the macrostructure determined by production process on the other hand.In order to determine failure of tubes sufficiently new test methods are proposed.
    Notes: Das Zeitstandverhalten von Thermoplastrohren unter mechanischer, thermischer und chemischer Belastung wird durch den Zeitstandinnendruckversuch geprüft.Dabei werden bei der Versuchsdurchführung in der bisher üblichen Form wesentliche Versagenskriterien nicht erfaßt. In dieser Arbeit wird im Rahmen einer Parameteranalyse zum Zeitstandinnendruckversuch am Beispiel des Systems LDPE/H2SO4 nachgewiesen, daß ein Versagen durch Medienaustritt („Schwitzen“) weit vor dem mechanischen Versagen der Prüfkörper durch Bruch stattfindet. Die Betrachtung der Schädigungsmechanismen innerhalb der Rohrwand mit licht- und elektronenmikroskopischen Methoden zeigen, daß die Übertragbarkeit der an relativ kleinen Proberohren ermittelten Zeitstandwerte auf Rohre größerer Dimensionen nicht gegeben sein kann. Dies ist sowohl durch die werkstoffspezifischen Mikrostrukturen teilkristalliner Thermoplaste, als auch durch die herstellungsbedingten Makrostrukturen begründet.Es werden Versuchsanordnungen vorgeschlagen, die es erlauben, das Versagen von innendruckbelasteten Rohrproben hinreichend zu erfassen.
    Additional Material: 17 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 49
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Materialwissenschaft und Werkstofftechnik 12 (1981), S. 72-72 
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 50
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Materialwissenschaft und Werkstofftechnik 12 (1981), S. 88-90 
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Description / Table of Contents: Influence of undeformable particles on the extrusion texture of composite materialsThe influence of α-Al2O3 particles on the extrusion texture of Ni-, Cu or CuZn30-composites has been investigated, variing particle size and interparticles spacing.The rods show a 〈100〉-recrystallization texture, which decreases with greater values of the interparticle spacing. In the case of the addition-free Cu and CuZn30 a random orientation distribution of the crystals was found. These results are discussed in comparison with the results found on Al—Al2O3-composites.
    Notes: Der Einfluß von Teilchengröße und Teilchenabstand einer unverformbaren Phase (α-Al2O3) auf die Texturausbildung einer metallischen Matrix wird an stranggepreßten Verbundstangen mit Nickel-, Kupferoder CuZn30-Matrix untersucht.Alle stranggepreßten Stangen weisen bei kleinem Teilchenabstand (2,5 m̈m) eine scharfe 〈100〉-Rekristallisationstextur auf, die mit zunehmendem Abstand schwächer wird. Im Falle von zusatzfreiem Cu bzw. CuZn30 ist sogar eine regellose Orientierungsverteilung der Kristalle zu beobachten.Die Ergebnisse werden im Vergleich zu den bei Al—Al2O3 Verbundstangen gefundenen diskutiert.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 51
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Materialwissenschaft und Werkstofftechnik 15 (1984), S. 109-117 
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Description / Table of Contents: Influence of Specimen Size on the Fracture Mechanical Behaviour of Sintered SteelFracture mechanics testing was carried out with small and big specimens using high-temperature sintered Fe-2%Cu-2.5%Ni-alloys in the densities of ρ = 7.1 and 7.4 g/cm3. These steels are often used in the manufacturing of PM-parts. Due to the different dismensions the crack propagation is for the bigger sizes faster than for the smaller sizes. Also the conditional fracture toughness of the big specimens is superiour to the toughness of the small specimens. But under consideration of a plain strain state for the big specimens and of a plain stress state for the small specimens valid fracture toughness values being independent from the specimen size can be calculated applying linear-elastic fracture mechanics.These results were obtained for both densities investigated. The increase of the density delivers principally better fracture mechanical data. Hereby the relation of strength data with the microstructure is also discussed.
    Notes: Am Beispiel von in der Formteilherstellung häufig verwendeten hochtemperaturgesinterten Fe-2%Cu-2,5%Ni-Legierungen in den Dichten ρ = 7,1 und 7,4 g/cm3 wurden bruchmechanische Untersuchungen an Klein- und Großproben vorgenommen. Aufgrund der unterschiedlichen Abmessungen ergibt sich bei Großproben eine größere Rißfortschrittsgeschwindigkeit und eine größere vorläufige Bruchzähigkeit als bei den Kleinproben. Durch Zuordnung des ebenen Dehnungszustandes zu den Großproben und des ebenen Spannungszustandes zu den Kleinproben läßt sich jedoch unter Berücksichtigung der jeweiligen plastischen Zonen ein von der Probenform unabhängiger gültiger Bruchzähigkeitswert auf der Basis der linear-elastischen Bruchmechanik berechnen.Diese Ergebnisse gelten für beide Dichtevarianten, wobei die Erhöhung der Dichte die bruchmechanischen Kennwerte grundsätzlich verbessert. Hierbei wird auch auf den Zusammenhang zwischen den Festigkeitskennwerten und dem Gefüge eingegangen.
    Additional Material: 10 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 52
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Materialwissenschaft und Werkstofftechnik 15 (1984), S. A35 
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 53
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Materialwissenschaft und Werkstofftechnik 15 (1984), S. 140-148 
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Description / Table of Contents: Remote Testing of Polymers with Photothermal Analysis of Thermal WavesAfter an introduction to thermal waves a comparison is made of photoacoustic detection methods (gas cell, piezoceramic) and photothermal detection arrangements (front surface and rear surface methods). Previously only photoacoustic methods have been applied to polymer related problems, while the advantages of photothermal measurements - remote and nondestructive evaluation - have been demonstrated on metals. The experimental part of this paper presents first steps to apply photothermal analysis of thermal waves to some problems of polymers: thickness measurement of thin layers; on-surface and subsurface defects; delamination of bonding and coating curing reactions; glass fibre content; orientation of fibres and molecules; aging processes.The present results indicate that the method can be used for nondestructive remote quality assurance of thin layers and foils. Further development is required to apply the method to nondestructive testing of thick walled components.
    Notes: Nach einer Einführung in die Grundlagen von Wärmewellen werden die photoakustischen Meßmethoden (Gaszelle, Piezokeramik) den photothermischen Meßmöglichkeiten (Frontseiten- und Rückseitenmethode) erläuternd gegenübergestellt. Kunststoffbezogene Problemstellungen wurden bisher nahezu ausschließlich mit photoakustischen Methoden bearbeitet. Die Vorteile der photothermischen Messungen - berührungslose und zerstörungsfreie Prüfung - konnten bisher an Metallen verdeutlicht werden. Der experimentelle Teil dieser Arbeit zeigt in ersten Schritten auf, daß auch bei Kunststoffen folgende Problemstellungen mit der Methode der photothermischen Wärmewellenanalyse bearbeitet werden können.Dickenmessung dünner Schichten; äußere und innere Fehlstellen; Haftungsfehler bei Verklebungen oder Beschichtungen; Vernetzungsreaktionen; Glasfaseranteil; Glasfaser- und Molekülorientierungen; Alterungsvorgänge.Die bisherigen Ergebnisse lassen sich in die zerstörungsfreie Qualitätssicherung dünner Schichten und Folien übertragen. Die zerstörungsfreie Prüfung von dickwandigen Bauteilen bedarf einer methodischen Weiterentwicklung.
    Additional Material: 15 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 54
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Materialwissenschaft und Werkstofftechnik 15 (1984), S. A101 
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 55
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Materialwissenschaft und Werkstofftechnik 12 (1981), S. 160-167 
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Description / Table of Contents: Separation of Acoustic Emission Signals by Computerized AnalysesFeatures extracted from acoustic emission signals by means of different analysis methods can be evaluated by the application of pattern recognition computer programs. By these methods it can be established, whether the employed features - maximum amplitude, signal rise time, pulse sum, pulse area, pulse energy and mean amplitude as well as simple characteristics of frequency spectra - are capable to distinguish acoustic emission signals or whether combinations of features lead to better results when single features fail.The efficiency of different analyses and the pattern recongnition programs is examined by four simulated types of signals. According to the employed analysis method there are distinct differences regarding the separation of acoustic emission. However, by applying feature combinations signal groups not separable by single analysis methods can be distinguished.
    Notes: Merkmale, die mit Hilfe verschiedener Analyseverfahren aus Schallemissionssignalen gewonnen werden, können durch den Einsatz von Rechenverfahren zur Mustererkennung bewertet werden. Durch Anwendung dieser Programme kann festgestellt werden, ob die verwendeten Merkmale - maximale Amplitude, Signalanstiegszeit, Schallsumme, Impulsfläche, Impulsenergie und mittlere Amplitude sowie einfache Kenngrößen aus Frequenzspektren - die Schallemissionssignale trennen können oder ob für den Fall, daß ein einzelnes Merkmal diese Aufgabe nicht löst, eine Kombination von Merkmalen zu einem besseren Ergebnis führt.Die Möglichkeiten der verschiedenen Analysen sowie der Mustererkennungsprogramme werden anhand von vier simulierten Signalarten überprüft. Je nach Analyseverfahren ergeben sich dabei deutliche Unterschiede hinsichtlich der Trennung der Schallemissionen. Jedoch kann selbst bei Signalgruppen, die mit einem Analyseverfahren nicht getrennt werden können, durch die Anwendung von Merkmalskombinationen die Unterscheidung verbessert werden.
    Additional Material: 10 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 56
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Materialwissenschaft und Werkstofftechnik 12 (1981), S. 174-181 
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Description / Table of Contents: Special Methods of Anti-Corrosion Treatment in Heat ExchangersAn anti-corrosion treatment must be adapted to the design of the heat exchanger and the conditions under which it is used. It is often the case, therefore, that highly specialized solutions are found. For the tubular heat exchanger, an organic coating has frequently proved suitable. The results obtained are determined by the construction, the surface characteristics of the components and paying attention to the risk of blister formation. The enamelling is problematic due to the complicated shapes involved and is still at the early stages of development. With water-cooled condensers, cleaning of the tubes while the equipment is running has proved successful. It alleviates the corrosion problem and assists the action of the inhibitors. Equipment made from materials such as titanium and austenitic CrNi steels, which are capable of being passivated, can frequently be retained in a passive state by adding air to the corrosive medium. In such cases, the excessive corrosion would normally necessitate the use of an expensive material. Where damage is caused by gaps and dead spaces it is not always possible to find a constructional remedy. A well-devised construction can subsequently be decisively influenced by manufacturing techniques relating to the structure, the state of internal stress or the surface condition.
    Notes: Ein Korrosionsschutz muß auf Bauart und Einsatzbedingungen des Wärmetauschers abgestimmt sein, so daß sich oft ganz spezielle Lösungen ergeben. Für den Röhrenwärmetauscher bietet sich häufig eine organische Beschichtung an. Konstruktion, Oberflächenbeschaffenheit des Halbzeugs und Rücksicht auf die Gefahr der Blasenbildung bestimmen den Erfolg. Die Emaillierung ist wegen der komplizierten Formen problematisch und noch am Anfang der Entwicklung. Bei wassergekühlten Kondensatoren hat sich das Rohrreinigungsverfahren unter laufendem Betrieb bewährt. Es entschärft das Korrosionsproblem und unterstützt die Wirkung von Inhibitoren. Apparate aus passivierbaren Werkstoffen, wie Titan und austenitischen CrNi-Stählen, lassen sich häufig durch eine Dosierung von Luft zum angreifenden Medium passiv halten, wo andernfalls infolge zu starker Korrosion ein teureres Material erforderlich wäre. Für Schäden, die durch Spalte und Toträume bedingt sind, läßt sich nicht immer eine konstruktive Abhilfe finden. Eine gut durchdachte Konstruktion kann durch fertigungstechnische Maßnahmen, die das Gefüge, den Eigenspannungs- oder Oberflächenzustand betreffen, noch entscheidend beeinflußt werden.
    Additional Material: 16 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 57
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Materialwissenschaft und Werkstofftechnik 12 (1981), S. A44 
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 58
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Description / Table of Contents: Influence of Different Degrees of Purity on the Fatigue Strength of Spring Steel 55 Cr 3One of the most important factors for construction and development of high strength springs is the material selection. In this connection the opinion is often represented in bibliography that material defects are the main reason for fractures.Besides surface defects (surface decarburization or rolling defects) essentially nonmetallic inclusions are described as causes of fractures. Therefore high degrees of purity are demanded especially for severe strained springs, which only can be obtained by very expensive special melting processes.By testing specimens of spring steel 55 Cr 3 with different degrees of purity in the present work the quantitative influence of nonmetallic inclusions on the fatigue life was to be examined. About 400 repeated torsion tests with annealed as well as annealed and shotpeened specimens were carried out accompanied by investigations to determine inclusions causing fracture and their size.
    Notes: Bei der Konstruktion und Entwicklung von Federn spielt die Werkstoffauswahl im Hinblick auf die Dauerschwingfestigkeit eine wichtige Rolle. In diesem Zusammenhang begegnet man im entsprechenden Schrifttum häufig der Auffassung, daß Werkstoffehler als Hauptursache von Brüchen infrage kommen.Neben den äußeren Fehlern, wie Randentkohlung, Walzfehler usw. werden bevorzugt nichtmetallische Einschlüsse als Ursache von Brüchen dargestellt, so daß vor allem bei hochbeanspruchten Federn Reinheitsgrade gefordert werden, die nur mit sehr teueren Sondererschmelzungsverfahren zu erreichen sind.In der vorliegenden Arbeit wurde versucht, an Proben der Federstahlgüte 55 Cr 3 (W.-Nr. 1.7176) mit gezielt unterschiedlich eingestelltem Reinheitsgrad den Einfluß von Größe und Anzahl nichtmetallischer Einschlüsse auf die Lebensdauer von Schwingproben quantitativ zu erfassen. Anhand von etwa 400 Torsionsschwellversuchen an vergüteten und polierten bzw. kugelgestrahlten Probestäben sollten diese Zusammenhänge aufgezeigt und durch begleitende Untersuchungen, insbesondere durch Ermittlung bruchauslösender Einschlüsse und deren Größenbestimmung, ergänzt werden.
    Additional Material: 20 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 59
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Materialwissenschaft und Werkstofftechnik 12 (1981), S. 227-229 
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Description / Table of Contents: Diffusion Bonding of Silicon CarbidesSilicon carbide is a material that is suitable for high temperature application, especially for heat exchangers at high temperatures.Besides the problem of producing large components out of ceramics a technique for joining silicon carbide has to be developed. At high temperatures the joint has to be gastight und sufficient strength must be guaranteed. Diffusion bonding proved to be a good technique. The temperatures necessary for diffusion bonding are around 1200 °C, inert atmosphere or vacuum was used. The parameters of the procedures are discussed and correlated to strength, microstructure and permeability for gases.
    Notes: Siliziumcarbid ist ein Werkstoff, der für Hochtemperaturanwendungen, besonders für Hochtemperatur-Wärmetauscher geeignet ist.Neben dem Problem, große Bauteile aus dieser Keramik zu produzieren, muß eine Fügetechnik entwickelt werden. Bei hohen Temperaturen sollen gefügte Teile gasdicht sein und ausreichende Festigkeiten müssen garantiert werden. Diffusionsschweißen hat sich dafür bewährt.Die Temperatur, die für die Diffusionsschweißung in Vakuum oder Schutzgas benötigt worden ist, lag bei 1200 °C. Es werden die Verfahrensparameter in Korrelation zu der Festigkeit des Verbundes, dem Gefüge und der Gasdurchlässigkeit diskutiert.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 60
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Materialwissenschaft und Werkstofftechnik 12 (1981), S. A55 
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 61
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Materialwissenschaft und Werkstofftechnik 12 (1981), S. A60 
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 62
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Description / Table of Contents: Influence of a Gradient of Composition on X-Ray Stress AnalysisIn the last years several factors were shown which lead to nonlinear sin2Ψ-distributions in x-ray stress analysis, like rotation of the principal stresses with respect to the normal to surface, steep stress gradients under the surface and a texture in the material under investigation.A fourth factor is revealed which becomes active, when gradients of the composition are present. In case of a chromized Fe-sample the influence on x-ray stress analysis is shown by measurement and theoretically as well. A method of correction is introduced, which is checked by use of a model sample.The x-ray residual stresses of the chromized Fe-sample are in accordance with such ones determined mechanically.
    Notes: Es wurden in den letzten Jahren verschiedene Einflußfaktoren aufgezeigt, die zu nichtlinearen sin2Ψ-Verteilungen bei röntgenographischen Spannungsmessungen führen. Hierzu gehören eine Drehung der wirksamen Hauptspannungen gegenüber der Probenoberflächennormalen, ein starker Gradient des Spannungszustandes nach der Tiefe unter der Oberfläche sowie das Vorliegen einer Textur im zu untersuchenden Material.Es wird hier ein vierter Einflußfaktor aufgezeigt, der in Kraft tritt, wenn Konzentrationsgefälle der Zusammensetzung auftreten. Anhand des Beispieles einer chromierten Fe-Probe wird meßtechnisch und theoretisch dieser Einfluß auf die röntgenographische Spannungsanalyse erörtert und eine Korrektur ermöglicht. Mit Hilfe eines Modellwerkstoffes wird die Methode überprüft. Es ergibt sich eine gute Übereinstimmung zwischen röntgenographisch und mechanisch ermittelten Werten der Eigenspannungen an dem chromierten Eisen.
    Additional Material: 15 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 63
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Materialwissenschaft und Werkstofftechnik 12 (1981), S. A63 
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 64
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Materialwissenschaft und Werkstofftechnik 12 (1981), S. 309-315 
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Experimental Factors Affecting Oxide GrowthResults of galvanostatic anodization of various metals with varying valve-metal behaviour including Nb, Ta, Zr, Ti, Al, W, Te, Sb, and Bi are compiled and compared with respect to the effect of various experimental factors such as surface pretreatment, stirring, solution composition, temperature of the bath, on the efficiency of oxide growth relative to that for other anodic processes. It is concluded that all of the above factors play an important role in the anodization of the non-typical valve metals, particularly Sb, Bi and W. Typical anodic charging curves associated with the process of oxide growth are given for several valve metals. Experimental data relevant to the phenomena of oxide breakdown are recorded and compared. The results indicate that the mechanism of breakdown varies for the same metal with variations in the experimental conditions.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 65
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Materialwissenschaft und Werkstofftechnik 12 (1981), S. 375-383 
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Description / Table of Contents: New Perceptions and Potentialities in Polymer-, Chemical-, Apparatus- and Piping ConstructionsAfter fundamental observations on diffusion and swelling behaviour of polymers follows an explanation for the “stress-cracking-corrosion” phenomenon also found in plastics, with the action of aggressive chemicals. This phenomenon is attributed to residual stresses due to diffusion.Fibre reinforced plastic constructions are difficult to classify into their reliability. New technics for the mechanical fabrication of important semi - finished products as for example pipes etc. have been developed. The scheme of a filament winding with a computer for winding pipes is introduced. At last is pointed to the development of the fabrication of GRP-constructions by robots.
    Notes: Nach grundlegenden Betrachtungen zum Diffusions- und Quellverhalten von polymeren Werkstoffen wird das auch bei Kunststoffen auftretende Phänomen der „Spannungsrißkorrosion“ bei Einwirkung aggressiver Medien beschrieben, das auf diffusionsbedingte Eigenspannungen rückgeführt werden kann.Faserverstärkte Kunststoffkonstruktionen sind wegen der weitgehend manuellen Fertigung in ihrer Zuverlässigkeit schwer einzustufen. Neue Techniken für die maschinelle Fertigung wichtiger Halbzeuge wie Rohre, T-Stücke und Krümmer wurden entwickelt. Das Schema einer rechnergesteuerten Wickelanlage zum Wickeln von Rohrformstücken wird vorgestellt.Abschließend wird auf die Entwicklung einer Fertigung von GFK-Bauteilen mit Hilfe von Robotern hingewiesen, durch die das Handlaminieren entfallen kann.
    Additional Material: 16 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 66
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Materialwissenschaft und Werkstofftechnik 12 (1981) 
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 67
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Materialwissenschaft und Werkstofftechnik 12 (1981), S. 411-420 
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Description / Table of Contents: Basic Chemistry and Physics of Macromolecular MaterialsPlastics are high polymers, and their molecular configuration differs from that of many classical materials. The molecular character governs their appearance and properties. They are produced by polymerisation, polycondensation and polyaddition processes.Plastics that are important for the construction of chemical engineering equipment are produced by polymerisation.Developments in plastics have by no means been completed. Although new classes of products can no longer be expected, the trends will be towards composites, materials systems and optimation of chemical and physical properties.
    Notes: Kunststoffe sind hochpolymere Werkstoffe und unterscheiden sich von vielen, sogenannten „klassischen Werkstoffen“ durch ihren molekularen Aufbau. Der molekulare Charakter bestimmt das Erscheinungsbild der Kunststoffe und gleichfalls ihre Eigenschaften. Herstellungsverfahren für Kunststoffe sind:Polymerisation, Polykondensation und Polyaddition.Die für den chemischen Apparatebau wichtigsten Chemiewerkstoffe werden nach dem Verfahren der Polymerisation hergestellt.Die Entwicklung der Kunststoffe ist noch keineswegs abgeschlossen. Wenn aber keine neuen Produktklassen mehr zu erwarten sind, so ist der weitere Weg der Kunststoffentwicklung gekennzeichnet durch Verbundwerkstoffe, Werkstoff-Systeme und Optimierung der chemisch-physikalischen Eigenschaften.
    Additional Material: 24 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 68
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Materialwissenschaft und Werkstofftechnik 12 (1981), S. 449-449 
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 69
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Materialwissenschaft und Werkstofftechnik 15 (1984), S. 411-415 
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Steel of the type 13%Cr6%Ni modified with 0.56%Mo allows to achieve favourable mechanical metallurgy properties, including decrease of the susceptibility to temper embrittlement. Application of two-stage tempering (first at 625°C, second at 575-600 °C) leads to counterbalanced mechanical properties and to the improvement of corrosion resistance in dependence on the modification of structure.The physical metallurgy characteristics were completed by potentiodynamic measurements. It was found that this evaluation indicates very sensitively the formation of austenite in the structure after applying tempering at intercritical temperatures. A model of austenite stabilization using the single and two-stage tempering method is presented.
    Additional Material: 12 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 70
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Materialwissenschaft und Werkstofftechnik 15 (1984), S. 436-436 
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 71
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Materialwissenschaft und Werkstofftechnik 15 (1984), S. A2 
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 72
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Materialwissenschaft und Werkstofftechnik 15 (1984) 
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 73
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Description / Table of Contents: Finsh and Solid Rolling of Automotive Running Gear and Drive ComponentsAutomotive parts, in particular running gear and drive components, are subject to high dynamic loads in regards to strength.When designing new parts, this is taken into account through dimensioning, material selection and constructional conception. Normally the mentioned measures will not be applied to old designs if, for example, they are subjected later to higher loads because of an increase in engine power output. Only the selection of different materials as well as strength increasing measures and methods remain for these parts.An important method is solid rolling. The examples of completed designs demonstrate the possible strength improvements, influence of rolling force on component strength as well as desired and undesired accompaniments.A comparison is made between solid rolling and other strength improving measures, such as inductive hardening.The results show the solid rolling method to be cost-favorable, very effective and safe in handling. The method has its limits in geometry (open rotation-symmetrical cross sections are required), size (component too large, cross section too filigreed) and application range (temperature) of components.
    Notes: Kraftfahrzeug-Bauteile, insbesondere Fahrwerkskomponenten und Antriebsbauelemente sind festigkeitsmäßig dynamisch hoch beansprucht.Bei der Neukonstruktion wird dem durch Dimension, Werkstoffauswahl und Konstruktionsprinzip Rechnung getragen. An bestehenden Konstruktionen, wenn diese beispielsweise durch spätere Leistungssteigerung höher belastet werden, scheiden in der Regel die genannten Maßnahmen aus. Hier bleiben dann neben anderer Werkstoffwahl nur festigkeitssteigernde Maßnahmen und Verfahren.Als ein bedeutendes Verfahren steht hier das Festwalzen. Die Beispiele ausgeführter Konstruktionen zeigen die möglichen Festigkeitssteigerungen, den Einfluß der Walzkräfte auf die Bauteilfestigkeit sowie erwünschte und unerwünschte Begleiterscheinungen.Es wird verglichen zwischen Festwalzen und anderen Maßnahmen zur Festigkeitssteigerung wie Induktivhärten.Das Ergebnis zeigt das Festwalzverfahren als kostengünstig, sehr wirksam und sicher in der Handhabung. Grenzen liegen verfahrensbedingt in der Geometrie (offene rotationssymmetrische Querschnitte notwendig), Dimension (Bauteil zu groß, Querschnitt zu filigran) und im Einsatzbereich (Temperatur) der Bauteile.
    Additional Material: 10 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 74
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Materialwissenschaft und Werkstofftechnik 15 (1984), S. 65-72 
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Description / Table of Contents: Activation Enthalpies and Mechanisms of Subcritical Crack Propagation in Aluminium Oxide CeramicsProgressive crack propagation has been investigated in the temperature range between 25 and 1000°C for two commercial varieties of Al2O3 ceramic, using double torsion specimens. 3 different temperature regions have been found, each of them with a different dependence of the effective activation enthalpie on the stress intensity factor. While at low temperatures the crack propagation rate is mainly controlled by the reaction of the grain boundary phase with the water vapor partial pressure of the environment, the softening of this phase is the predominent factor at high temperatures.
    Notes: An zwei Qualitäten kommerzieller Al2O3-Keramik unterschiedlichen SiO2-Gehalts wurde an Doppeltorsionsproben die langsame Rißausbreitung im Temperatubereich von 25 bis 1000°C untersucht. Es wurden drei Bereiche gefunden, die eine unterschiedliche Abhängigkeit der effektiven Aktivierungsenthalpien vom Spannungsintensitätsfaktor aufweisen. Bei niedrigen Temperaturen steuert im wesentlichen die Reaktion des Wasserdampfes der umgebenden Luft mit der Korngrenzenphase die Rißausbreitung, bei hohen Temperaturen spielt die Erweichung dieser Korngrenzenphase die entscheidende Rolle.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 75
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Description / Table of Contents: Ductility of Metallic Diffusion Type Coatings on Nickel-Based Alloys and its DeterminationA test method is being presented by which ductility properties of metallic diffusion coatings, which are used against hot corrosion e.g. on turbine blades, can be measured. The ductility measurements are based upon the acoustic emission during crack initiation within coated specimens under mechanical load. By plotting the acoustic emission and the stress vs. elongation simultaneously, the crack initiation stress vs. elongation simultaneously, the crack initiation stress of the coating and the 0,2%-proof stress of the substrate can be determined by the same experiment. Correlations between these two stress levels led to ductility characteristics and within the scope of these investigations to dependences on temperature, coating thickness, strain rate and thermal history of the coating/substrate system. The investigations were carried out on three different diffusion coatings combined with two nickel-base superalloys. Ductility measurements up to 850°C led to ductile-brittle-transition-temperatures as well as to temperature dependant stress and strain levels, below which the coatings on certain substrate behave in a ductile manner.
    Notes: Diffusionsschutzschichten gegen Heißgaskorrosion sind vielfach bei niedrigen Temperaturen spröde und werden erst bei höheren Temperaturen zäh. Für das Betriebsverhalten beschichteter Turbinenschaufeln z. B. ist die Kenntnis der Übergangstemperatur vom spröden zum zähen Verhalten von Bedeutung, wobei die Eigenschaften der Schutzschicht vom jeweiligen Trägerwerkstoff beeinflußt werden. - Es wird nun ein Prüfverfahren vorgestellt, mit dem an beschichteten Proben unter mechanischer Beanspruchung das Auftreten erster Anrisse in der Schutzschicht durch Schallemissionsmessungen nachgewiesen und gleichzeitig durch die Aufnahme eines Spannung-Dehnung-Schaubildes die relative Lage der Anrißspannung der Schutzschicht und der 0,2 Grenze des Trägerwerkstoffes erfaßt werden. Aus den durchgeführten Versuchen ließen sich Angaben über die Zähigkeit in Abhängigkeit von der Temperatur und anderen Einflußgrößen wie Schichtdicke, Dehngeschwindigkeit und thermischer Vorgeschichte ableiten. Auf diese Weise konnten für drei verschiedene Schutzschichten, dei mit zwei hochwarmfesten Nickellegierungen kombiniert waren, Spröde Zäh-Übergangstemperaturen bestimmt werden. Weiterhin ergaben sich bis zur höchsten Prüftemperatur von 850°C Spannungs- und Dehnungsgrenzen, unterhalb derer die untersuchten Schutzschichten auf den Trägerwerkstoffen rißfrei bleiben.
    Additional Material: 15 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 76
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Materialwissenschaft und Werkstofftechnik 15 (1984), S. 108-108 
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 77
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Materialwissenschaft und Werkstofftechnik 15 (1984) 
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 78
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Materialwissenschaft und Werkstofftechnik 15 (1984), S. 117-123 
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Description / Table of Contents: Ergebnisse von Untersuchungen mit einem instrumentierten Kerbschlaghammer an einer Molybdänbasislegierung, Nickelbasislegierungen und Incoloy 800Mit einem instrumentierten Pendelschlagwerk wurden Experimente an der Molybdänbasislegierung TZM, den Nickelbasislegierungen Nimocast 713 LC, Inconel 625, Nimonic 86, Hastelloy S und der Eisenbasislegierung Incoloy 800 durchgeführt. Die Ergebnisse werden unter den Gesichtspunkten der verbrauchten Schlagenergien und der dynamischen Bruchzähigkeit diskutiert.In allen Fällen war die Übereinstimmung zwischen den Energien, die am Schleppzeiger des Hammers abgelesen wurden und den Energien, die durch die Integration des Kraft-Weg Diagrammes ermittelt wurden, ausgezeichnet.Ein Verfahren für die Bestimmung der dynamischen Bruchzähigkeit für eine Last vs. Lastpunktverschiebungskurve mit hohen Oszillationen unter Verwendung einer gemittelten Kurve wurde vorgeschlagen. Verwendet man dieses Verfahren, findet man keinen deutlichen Einfluß der Experimente mit Hammer und Stössel (5,0 m/s und 0,1 m/s) auf die dynamische Bruchzähigkeit. Halbiert man die Fallhöhe, d.h. halbiert man die totale Schlagenergie, so werden die dynamischen Bruchzähigkeitswerte für die Legierungstypen erniedrigt.Niedrige absorbierte Schlagenergien sind oft verknüpft mit hohen Bruchzähigkeitswerten. Hier fehlt die Reserve in der Verformung und/oder im stabilen Rißwachstum.
    Notes: Experiments were performed on the molybdenum base alloy TZM, the nickel base alloys Nimocast 713 LC, Inconel 625, Nimonic 86, Hastelloy S, and the iron base alloy Incoloy 800 with an instrumented impact machine. The results are discussed in terms of absorbed impact energies and dynamic fracture toughness.In all cases the agreement between the energy determined by the dial reading and the energy determined by the integration of the load vs. load point displacement diagram was excellent.A procedure for the determination of the dynamic fracture toughness for load vs. load point displacement diagrams exhibiting high oscillations using an averaged curve is proposed. Using this procedure a pronounced influence of the experiments with tup and chisel (5.0 m/s and 0.1 m/s respectively) on the dynamic fracture toughness is not detectable. Using half the drop height, i.e. halving the total energy, lowers the dynamic fracture toughness values for these types of alloys. Low absorbed impact energies are often combined with high fracture toughness values. In these cases there is no or only a small reserve in deformation and/or stable crack growth.
    Additional Material: 18 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 79
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Materialwissenschaft und Werkstofftechnik 15 (1984), S. 149-153 
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Description / Table of Contents: Welding in Tank and Plant ConstructionSince a relatively limited number of plastics types are used, the welding tasks involved in chemical apparatus engineering can be accomplished with just a few welding techniques are well-known and welding can be carried out efficiently, reliably and economically by this means. In this respect, however, a number of important principles have to be observed. The DVS guidelines provide vital information on questions relating to calculation, design, personnel, equipment, material and testing. Extrusion welding enjoys prime importance as regards quality and economic aspects.
    Notes: Die Schweißaufgaben im chemischen Apparatebau werden an einer relative geringen Anzahl von Kunststofftypen mit wenigen Schweißverfahren bewältigt. Diese Verfahren sind in ihren Grenzen erfaßt und erlauben sichere und wirtschaftliche Schweißungen. Es sind hierbei allerdings eine Reihe wichtiger Grundsätze zu beachten. Die entsprechenden DVS-Richtlinien geben zu Berechnungs-, Gestaltungs, Personal-, Geräte-, Material- und Prüffragen wesentliche Hinweise. Vorrangige Bedeutung im Hinblick auf Qualität und Wirtschaftlichkeit im Behälter- und Apparatebau hat das Extrusionsschweißen.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 80
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Materialwissenschaft und Werkstofftechnik 15 (1984), S. 153-157 
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Description / Table of Contents: Long Term Testing of Welded Joints from HDPE under Complex LoadingTest methods to determine the long term weld-factors for heated tool butt weldings, extrusion weldings and hot gas weldings are presented. Instead of tensile bars welded pipers are tested under internal pressure to abbreviate the test times. The results of long term creep tests with welded and unwelded PE-HD pipes under the influence of several fluids are also discussed.
    Notes: Für die im Apparate- und Behälterbau am meisten angewandten Schweißverfahren: Heizelementstumpf-, Extrusions- und Warmgas-schweißen werden Prüfmethoden zur Bestimmung der Langzeit-schweißfaktoren vorgestellt. Als Prüfkörper werden hierbei geschweißte Rohre verwendet, um einen mehrdimensionalen Span-nungszustand zu realisieren und die Prüfzeiten zu verkürzen. Desweiteren wird der Einfluß einiger Medien auf geschweißte Rohre im Vergleich mit ungeschweißten Rohren untersucht.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 81
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Materialwissenschaft und Werkstofftechnik 15 (1984), S. 183-185 
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Description / Table of Contents: Experiences in Welding Highly Pure, Gas-Sensitive MaterialsHighly pure steels and non-ferrous react during processing, particularly welding, with atmospheric gases and change their service properties. Hence special measures are often necessary in forming and inert gas welding. Taking the specific example of a high pure chromium steel (superferritic), welding properties, processing data and selection of suitable inert gas torches are described. The possibility of applying this information to other materials such as titanium is discussed.
    Notes: Hochreine Stähle und Nichteisenmetalle reagieren bei der Verarbeitung, insbesondere beim Schweißen mit den Gasen der Luft und verändern ihre Gebrauchseigenschaften. Daher sind vielfach Sondermaßnahmen beim Formieren und Schutzgasschweißen notwendig. Speziell am Beispiel eines Chromstahles hoher Reinheit (Superferrit) werden die Schweißeigenschaften, Daten der Verarbeitung sowie die Auswahl geeigneter Schutzgasbrenner beschrieben. Vergleichende Hinweise und Anwendungsbeispiele für andere Werkstoffe wie z. B. Titan sind möglich.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 82
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Materialwissenschaft und Werkstofftechnik 15 (1984), S. 190-190 
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 83
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Materialwissenschaft und Werkstofftechnik 15 (1984), S. 199-206 
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Description / Table of Contents: Untersuchungen zum Einfluß der Hammergeschwindigkeit und der Auslagerung auf die dynamische Bruchzähigkeit für Inconel 625Mit einem instrumentierten Pendelschlagwerk wurden Experimente an der Nickelbasislegierung Inconel 625 im Anlieferungszustand und nach Auslagerung über 3,6 Ms (1000 h) bei 923 K (650°C) unter Anwendung unterschiedlicher Fallhöhen durchgeführt. Die verbrauchte Schlagenergie kann sowohl über den Schleppzeiger, über die Integration des Kraft-Lastpunktverschiebungs-Diagrammes als auch aus der Integration des Kraft-Zeit-Diagrammes bei gleichzeitiger Kenntnis der Schlaggeschwindigkeit v0 unmittelbar vor Auftreffen des Hammers auf die Probe ermittelt werden. In allen Fällen ist die Übereinstimmung gut.Es wird gezeigt. -daß die dynamische Bruchzähigkeit abhängig ist von der Hammergeschwindigkeit v0 und damit von der totalen Energie des Hammers bei unterschiedlichen Fallhöhen.-daß die Versprödung infolge Wärmebehandlung nicht mit einer Absenkung der Bruchzähigkeit verbunden ist, obwohl eine starke Abnahme der verbrauchten Schlagenergie beobachtet wird. Definiert man eine dynamische Spannung σ aus der Geschwindigkeitsabhängigkeit der Bruchzähigkeit, so ist σ größer für das versprödete Material im Vergleich zum Anlieferungszustand. Diese Tendenz ist von Zugversuchen her bekannt.-daß die dynamische Bruchzähigkeit mit der absorbierten Schlagenergie bis zum Lastmaximum für das wärmebehandelte Material korreliert werden kann, während für den Anlieferungszustand keine Abhängigkeit gefunden wird.Die Änderung der Hammergeschwindigkeit im Verlauf des Stoßprozesses ist nur klein für diesen Werkstofftyp.
    Notes: Experiments were performed with an instrumented impact machine using different drop heights, on the nickel base alloy Inconel 625 in the as-received state and after heat treatment for about 3.6 Ms (1000 h) at 923 K (650°C).The absorbed impact energy can be obtained either by the direct dial reading, by the integration of the load versus load point displacement diagram or by the integration of the load versus time diagram, knowing the initial impact velocity v0 of the tup. In all cases the agreement was excellent.It is shown that. -the dynamic fracture toughness is dependent on the tup velocity v0 and, as a consequence, on the total energy of the hammer at the different drop heights.-defining a dynamic stress σ from the velocity dependence of the fracture toughness, the stress σ is higher for the embrittled material - a tendency verified by tensile tests.-the dynamic fracture toughness can be correlated with the absorbed impact energy up to the load maximum for the heat treated material while the as-received material exhibits no such dependence.The change in the tup velocity during the impact process is only small for this type of material.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 84
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 85
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Materialwissenschaft und Werkstofftechnik 15 (1984) 
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 86
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Materialwissenschaft und Werkstofftechnik 15 (1984), S. 246-250 
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Description / Table of Contents: Schallemissionsprüfung von Wärmetauschern des Reaktors SaphirDie Schallemissionsanalyse ist eine zerstörungsfreie Prüfmethode, die zur Untersuchung und Überwachung von Strukturen und druckführenden Komponenten verwendet wird. Das Ziel der Messung am 5 MW Forschungsreaktor Saphir war die Untersuchung und Auswertung der hohen Betriebsgeräusche in den Wärmetauschern des Kühl-systems.Die Ergebnisse zeigten, daß von den 9 Wärmetauschern, die in 3 Gruppen angeordnet sind, 5 Wärmetauscher ein hohes Betriebsgeräusch aufweisen. Die Ursache ist auf die Schwingung der Rohrbündel in Wärmetauschern beim Durchfluß des Pool-Wassers zurückzuführen. Die axiale Ortung bestätigte, daß die Geräusche von mehreren Quellen verursacht werden.
    Notes: The acoustic emission technique is a non-destructive testing method used for inspection and surveillance of structures and pressurized components. In particular, the purpose of the measurement on the 5 MW research reactor SAPHIR was to investigate and evaluate the abnormally high noise levels during operation of the heat exchangers of the cooling system.The results showed that 5 heat exchangers out of the total of 9 (assembled in 3 groups) were responsible for the higher noise level. This is probably due to some abnormal vibration of the tube bundles therein, caused by the through-flow of the pool water. Indeed, attempts of localizing the source showed that there must be several, distributed sources.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 87
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Materialwissenschaft und Werkstofftechnik 15 (1984), S. 250-256 
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Description / Table of Contents: Ultrasonic Testing of Metal DepositsThe adhesive strength of Ni-deposits has been determined with the well known ring shear test and by a test procedure which usually is used to analyze the resistance of a material against cavitation. In this case the specimen is fastened at the top of an ultrasonic vibrator and oscillates in an aqueous fluid. The deposit/substrate interface is strengthened by high accelerative forces and by mechanical attack of imploding bubbles in the fluid. It was shown that this method is able to distinguish the effect of different pretreatment of the substrate surface. The test result is given as the duration of attack without any exfoliation of the deposit.
    Notes: Die Prüfung der Haftfestigkeit metallischer Überzüge auf z. B. metallischen Grundwerkstoffen spielt eine wichtige Rolle im Hinblick auf die Funktionalität der beschichteten Bauteile im Betrieb. Ihre Bestimmung ist nicht in einfacher Weise möglich, wenn es gilt, Zahlenwerte zu erhalten. Nachfolgend werden zwei Verfahren vorgestellt, von denen das eine, nämlich der ring-shear-test, schon seit längerer Zeit bekannt ist, das andere jedoch, die Untersuchung mit dem Ultraschallkoppelschwinger, neu entwickelt wurde. Die Heranziehung des ring-shear-testes dient in der vorliegenden Arbeit dem Vergleich, wobei hier bekanntlich Zahlenwerte mit der Dimension einer Spannung erhalten werden, während der Versuch mit dem Ultraschallkoppelschwinger Beständigkeitszeiten als Entscheidungskriterium liefert.Gleichzeitig ließ sich mit beiden Methoden der Einfluß der Vorbehandlung auf die Haftfestigkeit eindeutig nachweisen.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 88
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Materialwissenschaft und Werkstofftechnik 15 (1984), S. 257-264 
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Description / Table of Contents: Statistical Size Effect at Random LoadingResults of random tests are used to show the applicability of the theory of statistical size effect. The specimens of all the tests of this report were made from the aluminium alloy 7075 T 7351. The specimens were machined from plates (2000 × 1000 × 40 mm). The main dimension of the specimens corresponds with the rolling direction. A standard random load sequence of Gaussian type which is recommended for general application in fatigue testing was used as loading program [19].In a first test series notched round bar specimens (Fig. 2) were used to investigate the sequence effect. 30 specimens were tested with the standard load sequence, 30 specimens with the variable load sequence. All the other test conditions were kept constant. Fig. 4 shows that the scatter of lifetime (cycles to fracture) is not influenced by the load sequence.In a second test series flat specimens with central holes were tested (Fig. 5) in order to show the existence of a pure statistical size effect at random loading. If the specimen has 1, 3 or 7 holes and all the other test conditions are kept constant, only the size of the area where cracks can initiate is enlarged. The results which are plotted in Fig. 6 show a very clear size effect. The results of the 1-hole specimen (A = A0) were used to determine the constants of Eq. (5). By inserting A = 3 A0 resp. A = 7 A0 the other test results can be predicted. In a third test series round bar specimens with a circumferential notch with different notch root radius (ρ = 1 mm resp. ρ = 6 mm) were tested (Fig. 2, Table 1). The specimens were loaded in such a way that the maximum stress in the notch root and its time-dependence was equal. In this very common case, the stress integral must be determined by applying Eq. (3). Additional tests to determine k and numerical calculations were necessary to evaluate Eq. (3). The final results are plotted in Fig. 8. By inserting A = A0 resp. A = 5 A0 into Eq. (7) the results can be described.The basis of the applicability of the theory of statistical size effect is the weakest link concept. The examination of the fracture surface and X-ray analyses showed that there was a higher content of iron (Fig. 11) in those regions where the fatigue cracks initiated. It is supposed that inclusions of intermetallic Al-Fe particles are those weakest links in the structure, where fatigue cracks nucleate.
    Notes: Es wurde der Einfluß der Bauteilgröße auf das Anrißlebensdauerverhalten bei zufallsartiger Schwingbeanspruchung an gekerbten Prüfkörpern aus der Al-Legierung AlZnMgCu 1,5 (7075T7351) untersucht. Durch geeignete Prüfkörperwahl gelang eine Trennung des statistischen (Fehlstellenmodell) und des spannungsmechanischen (Stützwirkungsmodell) Effekts und damit der Nachweis des rein statistischen Einflusses der Baugröße. Darüber hinaus wurde gezeigt, daß das auf dem Fehlstellenmodell beruhende Rechenverfahren auch bei Änderung der Stützwirkung im Bauteil seine Gültigkeit bewahrt. Der Begriff der Fehlstelle konnte durch eine konkrete mikrostrukturelle Werkstoffinhomogenität ersetzt werden. Diese zufällig im Material verteilten Fehler werden als Ursache für die Lebensdauerstreuung angesehen. In diesem Zusammenhang konnte für eine auf einem stationären Gaußprozeß beruhende Lastfolge geklärt werden, daß die Lebensdauerstreuung nicht von der Lastspielreihenfolge abhängt, wenn das Beanspruchungskollektiv und der zeitliche Charakter des Lastablaufs erhalten bleiben.
    Additional Material: 11 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 89
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Materialwissenschaft und Werkstofftechnik 15 (1984), S. A65 
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 90
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Materialwissenschaft und Werkstofftechnik 15 (1984), S. 309-314 
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Description / Table of Contents: Oszillationen des Korrosionspotentials bei rostfreien StählenDie Korrosionspotentiale von rostfreien Stählen in chloridhaltigen Lösungen sind in Umgebungen, in denen weder Lochfraß noch Spaltkorrosion auftreten, konstant. In diesen Fall sind die Korrosionspotentiale weitgehend unabhängig von der Temperatur und der Chloridionkonzentration. Bei Stählen mit abnehmendem Korrosions widerstand oder mit zunehmender Temperatur und zunehmender Chloridionkonzentration tritt eine Situation ein, bei der das Korrosionspotential zu oszillieren beginnt - und zwar zwischen zwei Werten, die ungefähr dem Lochfraßpotential Ep und dem Repassivierungspotential Epp entsprechen. Diese Potentialoszillationen sind häufig von Lochfraß und Spaltkorrosion begleitet; andererseits gibt es Fälle, bei denen sogar nach langer Zeit kein Korrosionsanriß sichtbar ist. Die Oszillationen werden einem instabilen Passivitätsverhalten zugeschrieben.
    Notes: The corrosion potentials of stainless steels in chloride solutions for conditions significantly removed from those leading to pitting and crevice corrosion are constant and to a first approximation largely independent of temperature and chloride ion concentration. With increasing temperature and/or chloride ion concentration or with decreasing corrosion resistance there comes a situation when the corrosion potential begins to oscillate, between two and values roughly corresponding to Ep and Epp. These potential oscillations are often associated with pitting and crevice corrosion, although there are clear cases when no corrosion attack was visible even after prolonged exposure. The oscillations are attributed to unstable passivity.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 91
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Materialwissenschaft und Werkstofftechnik 15 (1984), S. 323-330 
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Description / Table of Contents: On the Interaction between Work-Material and Forming-Process and its Investigation by ExperimentsExperiments are described and discussed for determining material properties before metal forming as well as process parameters during the metal forming operation and workpiece properties after metal forming.Before metal forming “pure” properties of matter have to be determined which in many cases is achieved by standardized testing methods. During and after the forming operation, however, the testing methods of interest are not yet standardized to the same extent. In particular it is necessary after metal forming, to take into account the effect of geometry on the workpiece properties which results into modified conditions for testing material and workpiece properties.
    Notes: Es werden Versuche beschrieben und diskutiert, in denen Werkstoffeigenschaften vor dem Umformvorgang, Verfahrensparameter während der Umformung sowie Werkstoff- und Werkstückeigenschaften nach der Umformung erfaßt werden können.Zur Bestimmung von Werkstoffeigenschaften vor der Umformung stehen zahlreiche genormte oder sonstwie vereinheitlichte Prüfverfahren zur Verfügung. Dies ist bei Versuchen während und nach der Umformung nicht in gleichem Maße der Fall. Insbesondere muß nach der Umformung der Einfluß der Geometrie auf die Werkstückeigenschaften berücksichtigt werden, wodurch sich veränderte Bedingun-gen für Versuche zur Erfassung von Werkstoff- und Werkstückeigenschaften ergeben.
    Additional Material: 13 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 92
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Materialwissenschaft und Werkstofftechnik 15 (1984), S. 359-362 
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 93
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Materialwissenschaft und Werkstofftechnik 15 (1984), S. A83 
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 94
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Materialwissenschaft und Werkstofftechnik 15 (1984), S. 371-377 
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Description / Table of Contents: Bruchenergiemessungen an keramischen WärmedämmschichtenDie Bruchenergie von plasmagespritzten Wärmedämmschichten aus ZrO2 · MgO, ZrO2 · Y2O3, ZrO3 · CaO · Al2O3 und Al2O3 · TiO2 auf Metallsubstraten wurde sowohl für einen Adhäsionsbruch als auch für einen Kohäsionsbruch der Deckschichten mit Hilfe gekerbter Schichtverbundbiegeproben ermittelt. Die verallgemeinerte Energiefreisetzungsrate wurde als Maß für die Bruchenergie benutzt. Sie berücksichtigt die in der Kraft-Durchbiegungskurve der Proben auftretende Nichtlinearität. Das Versagen der Proben innerhalb der Deckschicht oder in der Grenzfläche wird von der Bildung und Vereinigung von sekundären Rissen in der Deckschicht begleitet. Diese Vorgänge verursachen das nichtlineare Verformungsverhalten und eine von der Rißgeschwindigkeit abhängige Bruchmorphologie.
    Notes: The fracture energy of plasma-sprayed thermal barrier coatings of ZrO2 · MgO, ZrO2 · Y2O3, ZrO2 · CaO · Al2O3, and Al2O3 · TiO2 on metal substrates is obtained for both adhesive and cohesive failure modes of the coatings using notched layer-bonded bend test specimens. The generalized energy release rate was employed as a measure of the fracture energy. It takes account of the nonlinearity found in the load-deflection curves of the specimens. The failure of the specimens within the coating or at the interface is accompanied by the formation and linking of secondary cracks in the coating. This causes the non-linearity in the deformation behaviour and a rate-dependent failure morphology.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 95
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Materialwissenschaft und Werkstofftechnik 15 (1984), S. 402-402 
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 96
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Materialwissenschaft und Werkstofftechnik 15 (1984), S. A93 
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 97
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Materialwissenschaft und Werkstofftechnik 15 (1984), S. 416-420 
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Description / Table of Contents: Improvement of Fatigue Properties by Roll PeeningWith sophisticated calculations a better understanding of the roll peening process is possible. Calculations together with experimental determination of the fatigue properties allow for a reduced test program to determine the fatigue limit of specimens with similar geometrical shape.
    Notes: Mit Hilfe verbesserter Berechungsverfahren lassen sich vertiefte Erkenntnisse über die Vorgänge beim Festwalzen gewinnen. Darüber hinaus bietet die rechnerische Analyse der Vorgänge zusammen mit der experimentellen Ermittlung der Schwingfestigkeit die Möglichkeit einer Übertragbarkeit auf andere Werkstoffzustände und Proben - bzw. Kerbformen. Hierdurch lassen sich Einsparungen durch verminderten Versuchsaufwand erreichen.
    Additional Material: 13 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 98
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Materialwissenschaft und Werkstofftechnik 15 (1984), S. 436-436 
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 99
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Particle and Particle Systems Characterization 1 (1984), S. 7-13 
    ISSN: 0934-0866
    Keywords: Chemistry ; Industrial Chemistry and Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Process Engineering, Biotechnology, Nutrition Technology
    Notes: In the application and the development of on-line methods for particle size analysis one has to distinguish three principally different problem areas:aallocation and preparation of a representative sample,banalysis of the sample,cevaluation of the results.Methods and problems connected with these areas will be discussed in this paper. Some of the methods available for rapid response analysis of particle size distributions mark the beginning of a new era of particle size analysis. One has to recognize however that a uniform solution of the problems of on-line particle size analysis is extremely difficult if not impossible to find. The boundary conditions vary to such an extent that similar methods or combinations of methods can rarely be used in different cases. Since instrument manufacturers will in most cases not be able to adopt their instruments to different industrial applications, specialists will have to solve the problem. One has to recognize, however, that not all of the steps described in this paper have been investigated to an extent which renders possible appropriate solutions. There is still room for improvement.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 100
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Particle and Particle Systems Characterization 1 (1984), S. 22-27 
    ISSN: 0934-0866
    Keywords: Chemistry ; Industrial Chemistry and Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Process Engineering, Biotechnology, Nutrition Technology
    Notes: For some time studies have been made relating the values obtained from simple shape description to bulk powder properties. More recently the detailed mathematical description of particle outline has become possible and quite powerful techniques have been developed. These techniques may be used for the regeneration by computer of the shape and, more importantly, for studies relating shape to individual particle behaviour and to bulk powder properties. Quite inadequate attention has been directed to the task of obtaining from the laboratory sample of the bulk powder a representative sample of shapes without bias. In this communication the considerations to be included in the sampling procedure are reviewed and a possible solution to the problems posed is presented.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...