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  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Archives of microbiology 39 (1961), S. 298-312 
    ISSN: 1432-072X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary It is proposed that the grouping of unicellular forms of bacteria into clusters or colonies may be the first step in the evolution of multicellular forms and that any further evolutionary advance would require the subordination of the impulses of the individual in favour of the needs of the “colony”. This latter relationship is exemplified by the group movement of certain aerobic sporeforming bacilli. A description of the nature of this movement on the surface of nutrient agar has been made. Studies on 54 strains showing this group movement reveal that they taxonomically constitute a nebulous group in Morphological Group II of the genus Bacillus according to the presently accepted system of classification (Bergey's Manual 1957). While the large majority of the strains studied morphologically resemble B. alvei, none exhibit the typical physiological characteristics of this species. Considering all the characteristics studied, the strains in our collection could be placed in an indefinite group comprising B. alvei, B. circulans, B. laterosporus and B. pulvifaciens. This however does not reflect any marked dissimilarities between the strains studied but rather the unsatisfactory taxonomy of the species enumerated. A re-examination of the determinative classification of these four species especially with reference to the unsatisfactory use of starch hydrolysis in the key to the genus is suggested.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Archives of toxicology 64 (1990), S. 332-335 
    ISSN: 1432-0738
    Keywords: Methyl isocyanate ; Scanning electron microscopy ; Osmotic fragility ; Erythrocytes ; ATPase
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Changes in surface morphology of rat erythrocytes were studied by scanning electron microscopy after a single and repeated exposure of methyl isocyanate under static conditions. Marked morphological changes (echinocytes and spherocytes) were observed, followed by an increase in osmotic fragility of the erythrocyte membrane. The activity of the membrane bound enzyme adenosine triphosphatase (Na+, K+, Mg++) was inhibited.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Springer
    Colloid & polymer science 253 (1975), S. 337-337 
    ISSN: 1435-1536
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 17 (1979), S. 4129-4133 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: No Abstract
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 19 (1981), S. 1517-1524 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The aqueous polymerization of methacrylamide (I) initiated by KBrO3-thioglycolic acid (TGA) has been studied at 30 ± 0.2°C in nitrogen. The rate is given by K[M]1.19 [thioglycolic acid]1 [KBrO3]0.53 for 10-15% conversion. Activation energy was found to be 53.96 kJ/mole (12.92 kcal/mole) in the investigated range of temperature 30-45°C. The role of addition of a series of aliphatic alcohols and some salts was also determined. The kinetics of polymerization was followed iodometrically.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
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  • 6
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 2665-2674 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The aqueous polymerization of methyl methacrylate (MMA) initiated by potassium persulfate (I)-thiomalic acid (TMA) redox couple has been studied at 30 ± 0.2°C under nitrogen atmosphere. The rate of polymerization is given by \documentclass{article}\pagestyle{empty}\begin{document}$$ R_p = K[{\rm MMA}]^{0.98} [{\rm K}_2 {\rm S}_2 {\rm O}_8]^x [{\rm TMA}]^{0.44} $$\end{document} up to 20.0 mmol/L TMA concentration, where x = 0.52 for the I concentration 0.6-10 mmol/L and x = 0.27 for higher I concentrations. The temperature had a marked effect on initial rate and maximum conversion. The overall energy of activation was found to be 11.79 kcal/mol (49.31 kJ/mol). Injection of more initiator (I) at intermediate stages enhanced both the initial rate and maximum conversion. Ag (I) and Fe (III) depressed initial rate as well as maximum conversion, while Cu (II) activated the polymerization. The effect of solvent was also studied.
    Additional Material: 10 Ill.
    Type of Medium: Electronic Resource
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  • 7
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 11 (1973), S. 751-762 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The polymerization of acrylamide initiated by the acidic permanganate-ascorbic acid redox pair has been studied in aqueous media at 30 ± 0.2°C in nitrogen atmosphere. The initial rate of polymerization has been found to be proportional to nearly the first power of the catalyst KMnO4 concentration within the range 6.0 × 10-3-14.0 × 10-3 mole/l. The rate is proportional to the first power of the monomer concentration within the range 4.00 × 10-2-12.0 × 10-2 mole/l. However, the rate of polymerization is independent of ascorbic acid concentration within the range 3.0 × 10-3-6.0 × 10-3 mole/l., but the further increase of the concentration depresses the rate of polymerization as well as maximum conversion. The initial rate increases but the maximum conversion decreases as the temperature is increased within the range 20-35°C. The overall energy of activation has been found to be 9.8 kcal/mole. The optimum amount of sulfuric acid is essential to initiate the polymerization but its presence in excess produces no effect either on the rate of reaction or the maximum conversion. Water-miscible organic solvents and salts, e.g., CH3OH, C2H5OH, (CH3)2CHOH, KCl, and Na2SO4, depress the rate. Slight amounts of MnSO4 · H2O and a complexing agent NaF increase the rate of polymerization. Cationic and anionic detergents have been found to decrease and increase the rate, respectively, while nonionic surfactants have no effect on the rate of polymerization.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
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  • 8
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 17 (1979), S. 531-538 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The polymerization of acrylamide (I) initiated by a potassium bromate - thioglycollic acid (TGA) redox pair has been studied in aqueous media at 30°C in a nitrogen atmosphere. The reaction order related to the catalyst concentration (KBrO3) was 0.501, which indicated a bimolecular mechanism for the termination reaction in the range of 1.0-3.0 × 10-3 mole/liter. The polymerization rate varied linearly with monomer (I) concentration over the range of 1.0-5.0 × 10-2 mole/liter. A typical behavior is observed, however, by changing the thioglycollic acid concentration. The initial rate of polymerization (Ri), as well as the maximum conversion, increases by increasing the temperature to 30°C, but the initial rate and the maximum conversion falls as the temperature rises above 30°C. The overall energy of activation is 6.218 kcal in the temperature range of 20-40°C. Water-miscible organic solvents, namely, CH3OH and C2H5OH, depress the rate of polymerization.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
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  • 9
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 3401-3405 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Novel polyhydrazides having inherent viscosities in the range of 0.24-0.38 dL g-1 were prepared by polymerizing a series of hydrazides with different diacid chlorides in polar aprotic solvents. These polymers display a wide range of solubility in a number of solvents. They start decomposing at about 200°C in air. Results of differential thermal and thermogravimetric analysis show that a steep weight loss takes place mainly in the range of 300-440°C.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
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  • 10
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 3599-3602 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
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