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  • 1
    Electronic Resource
    Electronic Resource
    Graft polymerization of methyl methacrylate onto nylon 6 using pentavalent vanadium as initiator (1981)
    Weinheim : Wiley-Blackwell
    Angewandte Makromolekulare Chemie 96 (1981), S. 59-68 
    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: Es wurde die durch 5wertiges Vanadium induzierte Pfropfcopolymerisation von Methylmethacrylat auf Nylon 6 untersucht. Die Pfropfausbeute sowie der Gesamtumsatz wurden in Abhängigkeit von der Vanadiumkonzentration, des Lösungsmittelgemisches sowie der Reaktionstemperatur bestimmt.
    Notes: Pentavalent vanadium ion (Vv)-induced graft polymerization of methyl methacrylate onto nylon 6 was investigated under a variety of conditions. Increasing the Vv-concentration up to 2 mmol/l was accompanied by an enhancement in grafting; the latter was not affected by further increase in Vv-concentration. Unlike grafting, the homopolymer and total conversion tended to increase by increasing Vv concentration. The graft yield enhanced significantly when the MMA-concentration was increased up to 3% further increase in MMA-concentration had no effect on grafting. Raising the polymerization temperature from 50° up to 70°C caused a significant increase in the rates of grafting, homopolymerization and total conversion. Using a solvent-water mixture as medium for polymerization affected considerably the magnitude of grafting. While using methyl alcohol, ethyl alcohol and acetone at any ratio in the solvent-water mixture resulted in decreased grafting, using an isopropyl alcohol-water mixture up to a ratio of 25 : 75 gave rise to increased grafting.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/apmc.1981.050960105
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  • 2
    Electronic Resource
    Electronic Resource
    Helix-Coil transition in polypeptides: A microscopical approach (1990)
    New York : Wiley-Blackwell
    Biopolymers 30 (1990), S. 357-367 
    Details
    ISSN: 0006-3525
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Analogous with the Potts model that describes the helix-coil transition in the isolated polypeptide chain (a Hamiltonian model allowing for the energy U of hydrogen bond formation) the number Q of conformational states of a repeating unit of the chain and the topology of Δ = 3 hydrogen bond formation (the hydrogen bond fixing three pairs of ϕψ chain rotations) has been constructed and the corresponding transfer-matrix has been obtained. In the thermodynamical limit, the partition function is expressed through the principal root of the cubic equation. The degree of helicity, the transition point and range, the correlation length, the number of junctions between the helical and coiling sections as well as the mean length of helical and coiling sections are calculated. Empirically introduced parameters of the Zimm-Bragg theory, constants of hydrogen bond formation s, and the cooperativity parameter σ as functions of microscopic parameters U, Q, and Δ are obtained by direct calculations. The behavior of this model was investigated at other topologies of the hydrogen-bond closing Δ = 2 and Δ = 4, and it was suggested that the actual polypeptide chain (Δ = 3) provides the optimum correlation of helical structure of the order of globule dimensions. An expression was obtained for the maximum correlation length of the order ξ ∼ Q(Δ-1)/2. For a System with solvent competing for the formation of hydrogen bonds with peptide groups a Hamiltonian model was constructed that took account of the energy E of the formation of hydrogen bond with the solvent and the number q of orientations of a solvent molecule about the peptide groups. It is shown that by the redefinition of the temperature parameter, the model with solvent reduces to the model of an isolated chain. Aside from the definition relationship that exists between the parameters of the theory U 〈 2E 〈 Uq and the ordinary helix-coil transitions (“melting”), the model also describes the transition from the coiling state to the helical one (“arrangement”) under heating. The change in temperature and transition range with solvent parameters was discussed and it was shown, that despite the difference in ΔT for the given polypeptide chain (Q = constant) with different solvent parameters, at “melting” and “arrangement,” the transition occurred at the same correlation length (the same cooperativity).
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/bip.360300313
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  • 3
    Electronic Resource
    Electronic Resource
    The helix-coil transition in polypeptides: A microscopic approach. II (1995)
    New York : Wiley-Blackwell
    Biopolymers 35 (1995), S. 75-84 
    Details
    ISSN: 0006-3525
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: In the framework of an earlier constructed model [N. S. Ananikyan et al. (1990) Biopolymers, Vol. 30. pp. 357-367], some analytical estimates for the correlation length and degree of helicity near the transition point were obtained in the case of an arbitrary topology of hydrogen bond closing (Δ). It was shown that the Zimm-Bragg cooperativity parameter σ is determined by the set of (Δ-1) amino acid residues and so is nonlocal. An analytic expression for cooperatively parameters in a heteropolypeptide chain was obtained and numerical calculations showed that in case of heteropolypeptide with random primary structure the nonlocality of cooperativity parameter influenced the temperature dependence of helicity degree. © 1995 John Wiley & Sons, Inc.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/bip.360350108
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  • 4
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    Comparison of produced fish protein hydrolysate from viscera and head of silver carp (Hypophthalmichthys molitrix) using alcalase enzyme and internal tissue enzymes (2021)
    In:  http://aquaticcommons.org/id/eprint/21909 | 18721 | 2018-01-16 10:47:13 | 21909 | Iranian Fisheries Science Research Institute
    Details
    Publication Date: 2021-07-04
    Description: In the present study, hydrolysed protein of viscera and head of Silver carp (Hypophthalmichthys molitrix) was compared using Alcalase enzyme and internal tissue enzymes at 2 and 4 hours. The result indicated that product by Alcalase (Treatment 1) had significantly higher protein and rate of hydrolysates than that produced by internal tissue enzymes (Treatment 2). So, the highest mean (±SD) protein (68.10±1.33) was related to treatment 1-head (with Alcalase enzyme) after 4 hours and the highest rate of hydrolysates (29.36±1.35) was related to treatment 1-head (with Alcalase enzyme) after 4 hours. The result indicated that rate of hydrolysates raised as time of hydrolysates increased. However the intensity and rate of hydrolysates is reduced. The highest rate of hydrolysates occurred at 120 minutes in the first. This mode was similar for two treatments. The result can be considered as the Alcalase was preferred to internal enzyme.
    Keywords: Chemistry ; Fisheries ; Biotechnology ; Fish processing ; Fish wast ; Hypophthalmichthys molitrix ; protein ; Silver carp ; tissue ; enzymes ; Iran
    Repository Name: AquaDocs
    Type: article , TRUE
    Format: application/pdf
    Format: application/pdf
    Format: 55-62
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  • 5
    Electronic Resource
    Electronic Resource
    Photodegradation of natural substances: Photooxygenation and Ozonolysis of 4-methoxy-7-methyl-5 H-furo [3,2-g][1]benzopyran-5-one (Visnagin) (1993)
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 335 (1993), S. 225-229 
    Details
    ISSN: 0941-1216
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The photooxygenation of 4-methoxy-7-methyl-5 H-furo[3,2-g][1]benzopyran-5-one (Visnagin, 1) in methanol in absence and in presence of a sensitizer (methylene blue) has been studied, 6-Formyl-7-hydroxy-5-methoxy-2-methylchromone (4a), methyl 7-hydroxy-5-methoxy-2-methylchromone-6-carboxylate (4b) and 7-hydroxy-5-methoxy-2-methylchromone-6-carboxylic acid (4c) could be isolated and identified in each case. The formation can be interpreted in terms of intermediate production of a 1.2-dioxetane like 2.A comparative study on the ozonolysis of Visnagin (1) in ethyl acetate both in absence and in presence of dimethyl sulfide, was also undertaken. Ozone attacks 1 either at the furan ring (to give 4a, c) or at both the furan and γ-pyrone site (to afford 10). Possible reaction mechanisms are considered and the structures of the new products are based upon compatible and spectroscopic evidences.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/prac.19933350303
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  • 6
    Electronic Resource
    Electronic Resource
    Untersuchung der Spannungsschicht des 18-8-Stahles mit Hilfe von Elektronenbeugung (1959)
    Weinheim [u.a.] : Wiley-Blackwell
    Materials and Corrosion/Werkstoffe und Korrosion 10 (1959), S. 499-501 
    Details
    ISSN: 0947-5117
    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 on the Stress-Layer of 18/8 Steel by means of Electron-DiffractionThe ferritic stress layer of 18/8 steel was investigated crystallographically as well as magnetically by means of electron diffraction. Furthermore its thickness was estimated magnetically.This method represents a convenient completion of 18/8 steels quality tests.
    Notes: Untersucht wurde die ferritische “Spannungsschicht” von 18/8-Stahl mit Hilfe von Elektronenbeugung sowohl kristallographisch als auch magnetisch, außerdem wurde ihre Dicke magnetisch abgeschätzt. Das neue Verfahren ergänzt die Güteprüfung von 18/8-Stahl in wertvollem Sinne.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/maco.19590100806
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  • 7
    Electronic Resource
    Electronic Resource
    Studies on the Pitting Corrosion of the Delta-52 Steel in aqueous solutions. 2. Variation of the pitting potential in relation to the concentration of the aggressive anion (1976)
    Weinheim [u.a.] : Wiley-Blackwell
    Materials and Corrosion/Werkstoffe und Korrosion 27 (1976), S. 630-636 
    Details
    ISSN: 0947-5117
    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 zur Lochkorrosion des Stahls Delta-52 in wässerigen Lösungen. -2. Änderung des Lochkorrosionspotentials in Abhängigkeit von der Konzentration des angreifenden AnionsDie potentiodynamischen anodischen Polarisationskurven wurden für eine Elektrode aus dem Stahl Delta-52 (0, 40, C, 0, 78Mn, 0, 045S, 0, 06p, 0, 23Si) aufgenommen; als Prüflösung diente verdünntes KOH mit und ohne Zusatz von Kaliumchlorid, -bromid und -jodid. Der auf dem Stahl vorhandene Oxidfilm beeinflußt die aktive Auflösung nicht, erst bei Potentialen über+2 V (ges. Calomal) tritt Passivität auf. Das Polarisationsverhalten des Stahls wird durch Zusatz der Halidionen nicht beeinflußt; oberhalb einer bestimmten Konzentration der Halide nimmt jedoch der Auflösungsstrom plötzlich steil zu, was auf den Beginn von Lochkorrosion hinweist; zwischen dem Lochkorrosionspotential und der Konzentration der Anionen besteht eine eindeutige Beziehung.
    Notes: Potentiodynamic anodic polarization curves have been traced for an electrode of the steel Delta-52 (0.40, 0.78Mn, 0.045 S, 0.06P, 0.23 Si): the aggresive media used were potassium hydroxide without and with additions of potassium chloride, bromide and iodide. The oxide film present on the steel surface does not inhibit active dissolution; only at potentials exceeding+2 (S. C. E.) passivity sets in. The polarization behaviour of the steel is not influenced by the addition of the halide salts; above a certain salt concentration, however, there is a sharp increase in dissolution current. This phenomenon is an indication of the start of pitting. Between the pitting potential and the anion concentration there exists a well defined relation.
    Additional Material: 10 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/maco.19760270905
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  • 8
    Electronic Resource
    Electronic Resource
    Synthesis of polymers containing carbazolyl groups via ringopening metathesis polymerization (ROMP) of a carbazolyl-substituted norborneneSystematic IUPAC name of norbornene: 8,9,10-trinor-2-bornene. derivative (1994)
    Weinheim : Wiley-Blackwell
    Macromolecular Rapid Communications 15 (1994), S. 155-159 
    Details
    ISSN: 1022-1336
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/marc.1994.030150211
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  • 9
    Electronic Resource
    Electronic Resource
    Asymmetric hydrosilylation of prochiral ketones in the presence of N-benzyl-N-methylephedrinium halometallates (1987)
    New York, NY [u.a.] : Wiley-Blackwell
    Applied Organometallic Chemistry 1 (1987), S. 435-439 
    Details
    ISSN: 0268-2605
    Keywords: Asymmetric hydrosilylation ; bis(N-benzyl-N-methylephedrinium) hexachloroplatinate(IV) ; N-benzyl-N-methylephedrinium bromotrichlororhodate(III) ; ( - )-bis(N-benzyl-N-methylephedrinium) dibromodichlorozincate(II) ; chiral synthesis, enantioselectivity ; Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: N-benzyl-N-methylephedrinium hexachloroplatinate(IV), bromotrichlororhodate(III), and dibromodichlorozincate(II) have been synthesized by reacting ( - )-N-benzyl-N-methylephedrinium bromide with K2PtCl6, RhCl3 · 4H2O and ZnCl2, respectively. The above halometallates have been found to catalyse the asymmetric hydrosilylation of acetophenone and 3-acetylpyridine with diphenylsilane. The hydrosilylation of 3-acetylpyridine in the presence of ( - )-N-benzyl-N-methylephedrinium zincate followed by silyl ether hydrolysis gives 1-(3-pyridyl)ethanol in ca 50% optical yield.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aoc.590010508
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  • 10
    Electronic Resource
    Electronic Resource
    Poly(2-vinylpyridine) complexes of palladium as catalysts of unsaturated alcohol hydrogenation (1986)
    Basel : Wiley-Blackwell
    Die Makromolekulare Chemie, Rapid Communications 7 (1986), S. 187-191 
    Details
    ISSN: 0173-2803
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/marc.1986.030070405
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