ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

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
  • Articles  (1,400)
  • Chemistry  (1,301)
  • Life and Medical Sciences  (99)
  • ASTROPHYSICS
  • 1965-1969  (1,211)
  • 1905-1909
Collection
  • Articles  (1,400)
Publisher
Years
Year
  • 1
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 12 (1968), S. 2191-2200 
    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: Infrared and NMR group-type methods for the analysis of the anhydride content of maleic anhydride copolymers such as poly(maleic anhydride-co-α-olefin) and the half ester content of their reaction products with alcohols are described. The infrared analyses are based on the integrated absorptivities of the anhydride carbonyl and the combination of the acid and ester carbonyl. The NMR method is based on the intensities of the various chemically shifted groups in the copolymer. The use of dimethyl sulfoxide as an auxiliary solvent has made the infrared analysis possible.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Cellular Physiology 72 (1968), S. 219-230 
    ISSN: 0021-9541
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Biopolymers 7 (1969), S. 5-19 
    ISSN: 0006-3525
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The osmotic pressure equation for nonideal, associating systems of the type nA +mB ⇄ AnBm, has been derived, by using the assumption yAnBm/yAnyBm = 1. This treatment can also be applied to related associations such as nA + mB ⇄ AB + AB2 + A2B + …. From osmotic pressure experiments on the pure reactants it is possible to obtain the molecular weights (MA and MB) of the reactants and also the virial coefficients (BAA and BBB) of the reactants. The osmotic pressure of a nonreacting mixture of A and B can be calculated from these measurements. It can be used along with osmotic pressure measurements on equilibrium mixtures of A and B to obtain expressions containing the equilibrium constant (or constants) and the cross-virial coefficients (BAB and BBA). Several procedures are described for the evaluation of the equilibrium constant (or constants) and the BAB or BBA terms. It appears that this procedure is a general one which is applicable to associations of the type nA + mB ⇄ AB + A2B + AB2 + …. By correcting for nonideal behavior, one should then be able to apply it to any method available for analyzing ideal associations of the types considered here. In addition it is possible, subject to certain restrictions, to analyze associations of the type 3A + B ⇄ A2 + AB.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 10 (1966), S. 75-80 
    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: Relaxation times of polyethylene melts have been measured by Aloisio, Matsuoka, and Maxwell. One implication regarding their observations is that the elastic properties of polymer melts must be time-dependent. In particular, the steady-flow shear modulus depends on the strain rate. Some interpretations of data in the literature have been based on concepts in rubber elasticity where the steady-flow modulus is an equilibrium value, independent of strain rate. We have used Pao's theory for viscoelastic flow together with measurements of relaxation times to discuss the strain rate dependence of the steady-flow shear modulus of melts. The existence of a strain rate-dependent shear modulus leads naturally to a nonlinear relation between shear stress and recoverable shear strain. The conclusions regarding the molecular weight dependence of the modulus also differ from interpretations based on rubber elasticity.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 5
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 13 (1969), S. 2721-2733 
    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: The influence of hydrogen bonding on the flow behavior of polymer melts at high shear rate has been investigated using a capillary extrusion rheometer. The systems studied were copolymers of ethylene and acrylic or methacrylic acid. Hydrogen bonding was found to substantially enhance both flow activation energy and viscosity level, as well as the degree of dependence of viscosity on rate of shear. It was also found that hydrogen bonding does not influence the critical shear stress for onset of “melt fracture.” The data support the view that hydrogen bonds act effectively as temporary (quasi-) crosslinks during the short time scales of deformation involved in flow at high shear rates.
    Additional Material: 10 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 6
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Biotechnology and Bioengineering 8 (1966), S. 337-352 
    ISSN: 0006-3592
    Keywords: Chemistry ; Biochemistry and Biotechnology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Oxygen uptake of Penicillium chrysogenum hyphae growing in automatically aerated deep cultures was the subject of local and periodical change. The change depended on the concentration of carbon dioxide which accumulated in the gas phase of system during the evolution of foam bubbles, and which was suddenly liberated when the foam was destroyed. The actual concentration of sunflower oil added as an antifoaming agent also influenced the oxygen uptake of culture.
    Additional Material: 10 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 7
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Biotechnology and Bioengineering 7 (1965), S. 343-354 
    ISSN: 0006-3592
    Keywords: Chemistry ; Biochemistry and Biotechnology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: The oxygen demand of Penicillium chrysogenum culture was supplied by an automatic aeration control system on the basis of the actual respiration of the cells. The simultaneous use of the automatic aeration apparatus and a turbomixer of great shear stress revealed that some effects of agitation are independent of aeration. These effects of agitation are manifested in two ways: (1) in the increased break down of the cell clumps, thus assuring large free cell surfaces for contact with the substrates; and (2) in the increased mixing effect, which assures a continuous mass transfer towardes the free cell surfaces. These effects of the agitation can improve the yield when the O2 level is maintained near to the saturation value. By means of an automatic aeration control system, the influence of carbon dioxide on the metabolism of hyphae and the production of penicillin was found to be demonstrably inhibitory when the dissolved oxygen was above the critical concentration in the culture liquid. This result is supporting evidence for the assumption that aeration is necessary to biosynthetic processes in two equally important ways: (1) to maintain the oxygen level above the critical value; and (2) to assure ventilation, by which the carbon dioxide level may be kept below its inhibitory critical value.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 8
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Biotechnology and Bioengineering 10 (1968), S. 133-150 
    ISSN: 0006-3592
    Keywords: Chemistry ; Biochemistry and Biotechnology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: The rate of dissolution and dehydration of CO2 in a liquid model system was investigated. Components in the model system established the main conditions which may exist, in the extracellular space of a microbiological culture liquid. The charge in voltage of a glass electrode was measured which indicated the formation of H+ ions in the H2CO3 ⇌ HCO3- H+ reaction. The rate of CO2 hydration increased with the increase of temperature from 0 to 40°C. Likewise the equilibrium of the reaction was shifted towards the forward reaction. Similar results were observed when the tip velocity of the impeller was increased. Data suggest that agitation promotes the dissolution of CO2 in the culture liquid through the reduction of gas-liquid film resistance in the diffusion of this gas. The rate of hydration of CO2 into the bulk of the liquid was independent of pCO2 above the surface of the liquid but depended on pCO2 in the gas bubble within the liquid. The concentration of HCO3- was, furthermore, influenced by the buffer components, buffer capacity, and the viscosity of the system. Since pCO2 and the HCO3- concentration in the extracellular space depend on both physical and chemical factors, the ventilation of a culture liquid necessitates both exhaust of CO2 from the gas bubbles of the culture broth and shift of the H2CO3 ⇌ HCO3- + H+ reaction towards the backward direction.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 9
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Biotechnology and Bioengineering 11 (1969), S. 1227-1232 
    ISSN: 0006-3592
    Keywords: Chemistry ; Biochemistry and Biotechnology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Bromination of the thiazole ring by the enzyme chloroperoxidase, produced by the fungus Caldariomyces fumago, was demonstrated. Both 2-acetoacetamido-4-methylthiazole and 2-acetamidothiazole were brominated on C-5 of the thiazole ring in the presence of chloroperoxidase, bromide, and hydrogen peroxide in 0.06 M Phosphate solution at pH 3.0. No reaction occurred in the absence of enzyme.
    Additional Material: 2 Tab.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 10
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Biotechnology and Bioengineering 7 (1965), S. 91-100 
    ISSN: 0006-3592
    Keywords: Chemistry ; Biochemistry and Biotechnology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: An automatic aeration controller was constructed to assure the optimal amount of oxygen for aerobic biosynthetic processes. A platinum electrode and a KCl bridge for the calomel electrode were inserted hermetically into the fermentor and were sterilized with the culture medium. The electrode potential developed at the surface of the Pt electrode continuously indicated the actual oxygen concentration of the medium. This served as the controlled variable of the system. The concentration of dissolved oxygen resulted from the actual demand and supply of the microorganism. The electrode potential, which was the measured variable of the process, operated a closed-loop automatic aeration system. The controller activated an air inlet valve in order to balance the controlled variable. The automatic controller operated in fermentors of industrial scale for long periods in a satisfactory manner.
    Additional Material: 3 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...