ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
feed icon rss

Your email was sent successfully. Check your inbox.

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

Proceed reservation?

Export
Filter
  • Chemistry  (375)
  • 1990-1994
  • 1970-1974  (375)
  • 1955-1959
  • 1935-1939
  • 1974  (375)
Collection
Keywords
Publisher
Years
  • 1990-1994
  • 1970-1974  (375)
  • 1955-1959
  • 1935-1939
Year
  • 1
    Electronic Resource
    Electronic Resource
    Studies on akroflex CD antioxidant loss from neoprene rubber. I. The determination of antioxidant content and the loss mechanism during aging (1974)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 18 (1974), S. 3543-3553 
    Details
    ISSN: 0021-8995
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: An analytical procedure for determining the antioxidant (i.e., Akroflex CD) content in neoprene rubber has been developed. The method is based on the infrared absorption analyses of chloroform extractables from the cured rubber at 1600 cm-1 and 1300 cm-1. Good agreement is found between these two independent sets of measurements. In an attempt to elucidate the antioxidant loss mechanism found with neoprene, thermal aging studies were carried out over the temperature range of 80°-200°C. Using the infrared analytical procedure, antioxidant loss rates at the different temperatures were established. The activation energy value (5.1 kcal/mole) for the loss rate as well as other aging data suggest that the antioxidant is lost by a diffusion mechanism.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1974.070181205
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Recovery of erythropoietin from anemic sheep plasma (1974)
    New York, NY [u.a.] : Wiley-Blackwell
    Biotechnology and Bioengineering 16 (1974), S. 1069-1079 
    Details
    ISSN: 0006-3592
    Keywords: Chemistry ; Biochemistry and Biotechnology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: A method is described for the large-scale preparation of erythropoietin from anemic sheep plasma. DEAE-cellulose and carboxymethylcellulose column chromatography was used to prepare Step II erythropoietin. A total of 168 sheep yielded 499 liters of plasma from which 323,000 IU of Step II erythropoietin was obtained.
    Additional Material: 3 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/bit.260160807
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Optimization in the recovery of a labile intracellular enzymePresented at the 166th American Chemical Society Meeting, Chicago, August, 1973. (1974)
    New York, NY [u.a.] : Wiley-Blackwell
    Biotechnology and Bioengineering 16 (1974), S. 1433-1447 
    Details
    ISSN: 0006-3592
    Keywords: Chemistry ; Biochemistry and Biotechnology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: A high molecular weight intracellular enzyme of Bacillus brevis ATCC 9999 is released when the organism is disrupted by sonication of homogenization. However, both processes also degrade the enzyme. Assays for protein release and specific enzymatic activity of the released protein indicate that both release and degradation can be represented by first-order kinetic models. Utilization of the difference between the kinetics of release and degradation allows optimization in the recovery of this enzyme for both the sonication and homogenization processes.
    Additional Material: 10 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/bit.260161102
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Response of the adenosine phosphate pool level to changes in the catabolic pattern of Saccharomyces cerevisiae (1974)
    New York, NY [u.a.] : Wiley-Blackwell
    Biotechnology and Bioengineering 16 (1974), S. 455-474 
    Details
    ISSN: 0006-3592
    Keywords: Chemistry ; Biochemistry and Biotechnology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Changes in the catabolic pattern of Saccharomyces cerevisiae, growing in continuous culture, were effected by altering the glucose feed rate or the dissolved oxygen concentration. The cytochrome concentrations and the adenosine phosphate pool level of the yeast in a series of steady states and during three transitions were measured and compared with the glucose uptake rate (QG), the respiration rate (QO2), and the rate of ethanolic fermentation (QE).Respiration was decreased at high glucose feed rates only if oxygen was low but cytochromes were glucose repressible at both high and low oxygen concentrations. In the main, QE and the levels of ATP, ADP, and AMP were decreased and cytochrome concentration were elevated at low QG values. No consistent relationship between any of the adenosine phosphate parameters and QO2 was discernible.Evidence is presented for the concept that the QG directly controls the adenosine phosphate pool level and that a relationship between the concentration of adenosine phosphate anhydride bonds and the adenosine phosphate level is constantly maintained.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/bit.260160403
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Immobilized enzyme reaction stability: Attrition of the support material (1974)
    New York, NY [u.a.] : Wiley-Blackwell
    Biotechnology and Bioengineering 16 (1974), S. 333-343 
    Details
    ISSN: 0006-3592
    Keywords: Chemistry ; Biochemistry and Biotechnology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: One of the main reasons for immobilizing an enzyme is to enable its reuse, or continuous use, in a reactor. Consequently immobilized enzyme stability is an important factor in enzyme reactor design. The performance of the reactor will decrease if during operation the support material disintegrates into smaller particles that pass out of the reactor system.When β-galactosidase is immobilized by covalent attachment to AE-cellulose, the smaller particles have a higher activity. After subjection of the immobilized enxyme to a shear stress the average particle size decreases and the total enzymic activity increases. A loss of small particles from the reactor, although constituting a small weight percent loss of support, will result in a disproportionately large loss in activity. The relevance of these observations to reactor performance is discussed.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/bit.260160304
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Influence of intraparticle diffuisional limitation on the observed kinetics of immobilized enzymes and on catalyst design (1974)
    New York, NY [u.a.] : Wiley-Blackwell
    Biotechnology and Bioengineering 16 (1974), S. 1081-1093 
    Details
    ISSN: 0006-3592
    Keywords: Chemistry ; Biochemistry and Biotechnology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Numerical solutions to the equations describing simultaneous mass transfer and enzymic reaction within porous spherical particles have been used to examine the effect of enzyme content and other parameters on the kinetic behavior of immobilized enzymes. These solutions have also been compared with experimental data for enzymes immobilized to DEAE-cellulose particles. The influence of particle size and enzyme content on catalyst design is discussed.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/bit.260160808
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Mixing by impeller agitation in continuous flow systems containing polysaccharide solutionsPresented at the Annual Meeting of the American Chemical Society Chicago, Illinois, August 26-31, 1973. (1974)
    New York, NY [u.a.] : Wiley-Blackwell
    Biotechnology and Bioengineering 16 (1974), S. 1283-1297 
    Details
    ISSN: 0006-3592
    Keywords: Chemistry ; Biochemistry and Biotechnology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: System response data for step changes in input tracer concentration have been obtained for two different impeller agitated continuous flow mixing systems containing aqueous polysaccharide solutions. The vessel volumes were 1.6 and 10.9 liters. Polysaccharide concentration, dilution rate, and impeller speed were varied according to a plan devised using dimensional analysis and assuming that bulk motion is the predominant mass transport mechanism in the system. The data show that this is not true and that serious errors may occur if scale-up calculations are based on assuming that bulk motion predominates. Under the operating conditions used, perfect mixing was not observed.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/bit.260160911
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Turbulent drag reduction in fiber-polymer systems: Specificity considerations (1974)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 20 (1974), S. 1218-1219 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690200626
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Effect of phase-volume ratio and phase-inversion on viscosity of microemulsions and liquid crystals (1974)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 20 (1974), S. 510-514 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Microemulsions, which are optically transparent oil-water dispersions, were spontaneously produced upon mixing hexadecane, hexanol, potassium oleate, and water in specific proportions. The viscosity of the microemulsions was measured for several water/oil ratios including the phase-inversion region. The striking optical and viscosity changes observed at specific water/oil ratios were in agreement with the proposed mechanism of phase-inversion, namely, water spheres → water cylinders → water lammellae → continuous water phase, for this system. In the phase-inversion region, the dispersion exhibited birefringence and rheopectic properties. An extremely high viscosity (〉 100,000 cps) exhibited by the dispersions between water/oil ratios of 2.0 and 3.5 were explained in terms of ion-dipole association between oleate and hexanol molecules on adjacent droplets.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690200311
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Kohlenstoffäden (1974)
    Weinheim : Wiley-Blackwell
    Angewandte Makromolekulare Chemie 40 (1974), S. 423-443 
    Details
    ISSN: 0003-3146
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Since a few years the development of carbon fibres from polyacrylonitrile (PAN) is concentrated in particular on improvements of the stabilization stage, i.e. of the early stage of the thermal degradation of PAN.The chemical and physical changes of PAN in the temperature range from 150 to 350°C influencing the properties of carbon fibres are discussed. According to the complex reaction process there exists a variety of possible technical procedures. In conformity with the actual knowledge it may be advantageous to substitute the usual stabilization treatment of PAN in air by a catalytic treatment in fluid reaction mediums. Nitroaromatic compounds in the presence of SnCI4 adducts are most suited for this purpose. In this way a remarkable shortening of the stabilization time is realized without diminishing the quality of the resulting carbon fibres.
    Notes: Die Entwicklung von Kohlenstoff-Fasern aus Polyacrylnitril (PAN) konzentriert sich seit einigen Jahren insbesondere auf Verfahrensverbesserungen der sog. Stabilisierungsstufe, d. h. auf das Frühstadium des thermischen Abbaus von PAN.Es werden die chemischen und physikalischen Veränderungen des PAN im Temperaturbereich zwischen 150 und 350°C diskutiert, die die Endeigenschaften der Kohlenstoff-Fasern wesentlich bestimmen. Aufgrund des komplexen Reaktionsgeschehens ist der Stand der Technik durch eine Vielfalt von möglichen Verfahrensvarianten gekennzeichnet. Nach dem heutigen Wissensstand ist es naheliegend, die herkömmliche Stabilisierungsbehandlung des PAN in Luft durch eine katalytisch beschleunigte Behandlung in flüssigen Reaktionsmedien zu ersetzen. Für eine solche Behandlung eignen sich insbesondere Nitroaromaten in Gegenwart von SnCl4-Addukten. Dadurch wird eine erhebliche Verkürzung der Stabilisierungszeit ohne nachteilige Qualitätseinbußen bei den resultierenden Kohlenstoff-Fasern erzielt.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/apmc.1974.050400120
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...