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
  • 1
    facet.materialart.
    Unknown
    Expression of procollagen C-proteinase enhancer-1 in the remodeling rat heart is stimulated by aldosterone (2006)
    Elsevier
    Details
    Publication Date: 2006-03-01
    Print ISSN: 1357-2725
    Electronic ISSN: 1878-5875
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Published by Elsevier
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 2
    Electronic Resource
    Electronic Resource
    Zur Charakterisierung der Siebröhren-Kallose (1957)
    Springer
    Cellular and molecular life sciences 13 (1957), S. 22-23 
    Details
    ISSN: 1420-9071
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Callose of sieve plates from the phloem ofVitis vinifera is characterized by a high density of 1.62 and a refraction index of 1.532±0.002. The X-ray diffraction pattern yields 5 diffuse rings, the strongest of which indicates a periodicity of 15.5 Å.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02156942
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Heredozelluläre Strahlenschäden im Hoden des Zahnkarpfens Lebistes reticulatus (1957)
    Springer
    Naturwissenschaften 44 (1957), S. 19-20 
    Details
    ISSN: 1432-1904
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology , Natural Sciences in General
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00629346
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Die Wirkung der Röntgenstrahlen auf den Hoden und die sekundären Geschlechtsmerkmale von Lebistes reticulatüs Peters (1957)
    Springer
    Journal of comparative physiology 40 (1957), S. 492-528 
    Details
    ISSN: 1432-1351
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Zusammenfassung 1. Infantile, juvenile und adulte Männchen von Lebistes reticulatus (Pisces, Cyprinodontae) wurden mit Röntgenstrahlen (Dosen: 500, 1000, 2000, 3000 und 4000 r) bestrahlt. Die histologische Untersuchung der bestrahlten Tiere ergab folgendes: a) Das empfindlichste Stadium der Spermatogenese sind die sekundären Spermatogonien. Im Vergleich dazu erweisen sich Spermatiden und Spermien und (im Gegensatz zu vorliegenden Literaturangaben) auch die Spermatozyten I. und II. Ordnung sowie die Reifeteilung als relativ strahlenresistent. b) Die Empfindlichkeit der Spermatogonienzysten ist um so größer, je älter sie sind. Durch selektiven Ausfall der empfindlichsten Stadien entsteht im Spermatogenesezyklus eine Lücke, die mit steigender Dosis immer größer wird, bis nur noch Primärspermatogonien und Reifungsstadien von der Meiose ab vorhanden sind. c) Die Primärspermatogonien (Urspermatogonien und Zysten mit 2–32 Zellen) bleiben äußerlich unverändert, solange sie sich nicht teilen. Bei einem Teil dieser Zellen erweist sich jedoch bei der nächsten Zellteilung der Kernapparat als gestört (Chromosomenstörungen = sog. Sekundäreffekte). Die Zahl der geschädigten Zellen ist dosisabhängig. Der Zeitpunkt des Wiederauftretens normaler (vom Sekundäreffekt ungeschädigter) Spermatogonienmitosen und damit der Wiederbeginn der Spermatogenese schiebt sich mit zunehmender Dosishöhe immer weiter hinaus. Infolgedessen kann es vorübergehend zu einer Depopulation des Hodens kommen. d) Die somatischen Hodenelemente sind sehr strahlenresistent. Abgestorbene Zellen des Keimepithels werden von den Wandzellen der Zyste (Sertolizellen) resorbiert. 2. Neben den von anderen Objekten her bekannten Formen der Zellschädigung (Frühbzw. Sekundäreffekte, Kernpyknosen usw.) wurden Spätschäden an den aus bestrahlten Primärspermatogonien hervorgegangenen Zysten beobachtet. Diese betreffen alle Abkömmlinge einer bestrahlten Mutterzelle und können sowohl im diploiden Zustand (in älteren Spermatogonienzysten) wie auch im haploiden Zustand bei der Spermienbildung auftreten. Die Strahlenschädigung einer Zelle kann also über mehrere Zellteilungen hinweg latent weitergegeben werden („heredozelluläre Wirkung“). 3. Ein „Mitosestop“ von längerer Dauer wurde auf keinem Stadium der Spermatogenese beobachtet. 4. Bei Dosen über 1000 r wurden in den ersten 2–3 Wochen nach der Bestrahlung Hautschäden (Verfärbung, Nekrosen) und andere somatische Schäden beobachtet. Diese klingen (sofern sie nicht tödlich sind) verhältnismäßig rasch wieder ab und beeinflussen die Reaktion des Hodens anscheinend nicht wesentlich. 5. Bei gleichbleibender Dosis ist die Wirkung auf den juvenilen Hoden um so geringer, je jünger die Fische sind. Dagegen sind die Jungfische gegenüber den somatischen Schäden sehr viel empfindlicher als geschlechtsreife Männchen.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00343748
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Berechnung der Läufererwärmung von Turbogeneratoren mittels der Methode der äquivalenten Wärmequellennetze (1957)
    Springer
    Electrical engineering 43 (1957), S. 133-140 
    Details
    ISSN: 1432-0487
    Source: Springer Online Journal Archives 1860-2000
    Topics: Electrical Engineering, Measurement and Control Technology
    Notes: Zusammenfassung Aus dem angeführten Beispiel ist ersichtlich, daß trotz äußerst einfachen Formeln, die sich aus der Benutzung der Methode der äquivalenten Wärmequellennetzes ergeben, ein Ergebnis erhalten wird, daß dem mittels eindimensionaler Wärmeströmung errechnetem, gleichwertig ist. Dabei ist der gesamte Rechenaufwand bedeutend geringer und einfacher1. Die Resultate sind sehr instruktiv und durchsichtig, denn das Wärmequellennetz-Schema gibt ein gutes Bild der thermischen Verhältnisse und der thermischen Belastung des Läufers. So ist z. B. ohne weiteres zu ersehen, in welchem Verhältnis der Einfluß der einzelnen Größen d L ,ϑ 2 undϑ 3 usf. auf die Wärmeabfuhr ist, oder daß z. B. bei relativ geringer Verbesserung des Wärmeüberganges im Ventilationsspalt, der Temperaturanstieg bei verringerter Nutzahl bedeutend geringer sein wird, usf. Es sei allerdings bemerkt, daß natürlich die richtige Zusammenstellung des Netzschemas und die richtigen Formeln zur Wertbestimmung der Widerstände äußerst wichtig sind2.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01479339
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Effect of Certain Nucleic Acid Components Upon the Status of Iron, Deoxyribonucleic Acid, and Lime-Induced Chlorosis in Fruit Trees (1957)
    [s.l.] : Nature Publishing Group
    Nature 179 (1957), S. 1015-1016 
    Details
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] IN the course of a study of the metabolism of nucleic acids, a close relation was found between the level of nucleic acids and the status of inorganic nutrients in fruit trees. Thus it was found that the addition of adenine and guanine causes an increase of deoxyribonucleic acid and brings about ...
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1038/1791015a0
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Age Hardening of Forged Aluminium Components – Mechanical Properties and Distortion Behaviour after Gas Quenching (2006)
    s.l. ; Stafa-Zurich, Switzerland
    Materials science forum Vol. 519-521 (July 2006), p. 383-388 
    Details
    ISSN: 1662-9752
    Source: Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: For quenching of age hardenable aluminum alloys today predominantly aqueousquenching media are used, which can lead due to the Leidenfrost phenomenon to a non-uniformcooling of the parts and thus to distortion. In relation to the conventional quenching procedures inaqueous media, gas quenching exhibits a number of technological, ecological, and economicaladvantages. The quenching intensity can be adjusted by the variable parameters gas pressure, gasvelocity as well as the kind of gas and thus can be adapted to the requirements of the component.By the higher uniformity and the better reproducibility, gas quenching offers a high potential toreduce distortion. Cost savings would be possible, because of reduced distortion and therefore lessreworking. High-pressure gas quenching with nitrogen or helium, as well as air quenching atambient pressure in a gas nozzle field was applied to the spray formed aluminum alloyAl-17Si-4Fe-3Cu-0.5Mg-0.4Zr (DISPAL S232). Hardness and tensile tests have been carried out todetermine the mechanical properties after gas quenching and aging compared to water quenching.The distortion behavior of a forged aluminum component of the spray formed alloy was examinedafter gas quenching and after water quenching. Gas quenching showed remarkable advantagesregarding distortion
    Type of Medium: Electronic Resource
    URL: http://www.tib-hannover.de/fulltexts/2011/0528/02/13/transtech_doi~10.4028%252Fwww.scientific.net%252FMSF.519-521.383.pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    New Light-Weight Aluminium Alloys with High Mg〈sub〉2〈/sub〉Si-Content by Spray Forming (2006)
    s.l. ; Stafa-Zurich, Switzerland
    Materials science forum Vol. 519-521 (July 2006), p. 1245-1250 
    Details
    ISSN: 1662-9752
    Source: Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Aluminum alloys with high Mg2Si-content (〉10 %) offer the possibility of a significant decreasein density and an increase in stiffness at the same time. But these alloys can hardly be produced incasting processes, due to an oxidation and a generation of pores by hydrogen solubility of the melt.Furthermore, the usual solidification rate is not sufficient for a fine microstructure morphology. Afine distribution of Mg2Si is possible by spray forming, where a coarsening of the particles can beavoided due to a higher solidification rate. Different aluminum alloys with high Mg2Si-content(〉10 %) have successfully been produced by spray forming, extrusion and age hardening.Mg-excess as well as Si-excess has been investigated. An additional alloying with copper leads to afurther increase in strength by the precipitation sequence of Al2Cu. The new light-weight aluminumalloys have been investigated regarding age hardening, physical and mechanical properties.Densities of 2.5-2.6 g/cm3 and Young´s modulus of approx. 80,000 MPa have been found.Microstructures were dense, homogeneous and of fine morphology. The yield strength of thesealloys reached values of approx. 400 MPa after artificial aging, whereby only a slight decrease forthe hot yield strength was observed up to a temperature of 200 °C. Applications of the newlight-weight aluminum alloys can be expected where a reduced density together with a high hotyield strength would lead to a more compact design in high temperature environments, e.g. incombustion engines
    Type of Medium: Electronic Resource
    URL: http://www.tib-hannover.de/fulltexts/2011/0528/02/13/transtech_doi~10.4028%252Fwww.scientific.net%252FMSF.519-521.1245.pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Continuous Cooling Transformation (CCT) Diagram of Aluminium Alloy Al-4.5Zn-1Mg (2006)
    s.l. ; Stafa-Zurich, Switzerland
    Materials science forum Vol. 519-521 (July 2006), p. 1467-1472 
    Details
    ISSN: 1662-9752
    Source: Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Age hardening is one of the most important processes to strengthen aluminium alloys. Itusually consists of the steps solution annealing, quenching and aging. For heat treatmentsimulations as well as for the appropriate choice of quenching processes in heat treatment shops,knowledge of the temperature- and time-dependent precipitation behaviour during continuouscooling is required. Quenching should happen as fast as necessary to reach high strengths, but alsoas slow as possible, to reduce residual stresses and distortion. This optimal quenching rate of analuminium component depends on its chemical composition, initial microstructure and solutionannealing parameters as well as on its dimensions. Unfortunately continuous cooling transformation(CCT) diagrams of aluminium alloys do almost not exist. Instead isothermal transformation (IT)diagrams or given average quenching rates are used to estimate quenching processes, but they arenot satisfying neither for heat treatment simulations nor for heat treatment shops.Thermal analysis, especially Differential Scanning Calorimetry (DSC) provides an approach forCCT-diagrams of aluminium alloys, if the relevant quenching rates can be realized in the DSCequipment.The aluminium alloy Al-4.5Zn-1Mg (7020) is known for its relatively low quenchingsensitivity as well as for its technical importance. The complete CCT-diagram of 7020 with coolingrates from a few K/min to some 100 K/min has been recorded. Samples have been solutionannealed and quenched with different cooling rates in a high speed DSC. The resulting precipitationheat peaks during cooling have been evaluated for temperature and time of precipitation start, aswell as their areas as a measure for the precipitate amount. Quenched samples have been furtherinvestigated regarding their microstructure by light and electron microscopy, hardness after agingand precipitation behaviour during re-heating in DSC. The CCT-diagram correlated very well withthe microstructure, hardness and re-heating results. A critical cooling rate with no detectableprecipitation during continuous cooling 155 K/min could be determined for 7020. A model tointegrate the CCT-diagram in heat treatment simulation of aluminium alloys is under development
    Type of Medium: Electronic Resource
    URL: http://www.tib-hannover.de/fulltexts/2011/0528/02/13/transtech_doi~10.4028%252Fwww.scientific.net%252FMSF.519-521.1467.pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Stoffwechselphysiologische Untersuchungen an Hydrogenase enthaltenden Grünalgen (1957)
    Springer
    Archives of microbiology 27 (1957), S. 166-181 
    Details
    ISSN: 1432-072X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00410266
    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...