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  • 1
    Electronic Resource
    Electronic Resource
    Crystalline modifications of cellulose. Part V. A crystallographic study of ordered molecular arrangements (1960)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 42 (1960), S. 173-188 
    Details
    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: With the arrangements of molecular chains postulated in Part III as a basis, crystal structures for the ordered regions of ramie and regenerated celluloses have been set up. Comparison of the (hkl) x-ray intensities calculated for cellulose I structures with the measurements reported in Part IV reveals serious discrepancies on the first layer-line. From extensive calculations over a range of structures, it appears that no conventionally ordered structure built from a P21 unit cell of approximate dimensions 8.2 × 10.3 × 7.9 A., β = 84°, can be expected to yield as weak (h1l) planes as are observed. An element of randomness in the polarity of the chains would diminish the discrete intensities on the higher layers relative to the (h0l) reflections and so be more in accord with experiment. For cellulose II, attention was concentrated on antiparallel chain structures with the r shift near 0.29. Although the overall agreement was better than for cellulose I, such structures did not account for the very weak low-order (h1l) reflections observed. The disparity was not reduced by types of disordering acceptable on stereochemical and spectroscopic grounds. The major part of the disagreement is tentatively attributed to regarding the observed coherent scattering as emanating from fully ordered unit cells of the accepted dimensions and symmetry, and to neglecting contributions from oriented amorphous regions.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1960.1204213920
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  • 2
    Electronic Resource
    Electronic Resource
    Proton magnetic resonance absorption in dry nylons 66 and 610 (1962)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 59 (1962), S. 271-281 
    Details
    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: A comparison of the temperature dependence of the nuclear resonance line-width and second moment for dried chip and rod samples of nylon 66 and 610, as measured by several authors, reveals discrepancies within the range 80 to 400°K. Room temperature measurements with a Pound-Watkins spectrometer suggest that neither linewidth nor second moment varies greatly with radiofrequency field, although saturation may occur at low temperatures. It is concluded that the nuclear resonance differences reflect sample differences, at least for the higher temperatures. Evidence is considered for the decomposition of the continuous nuclear resonance changes in polyamides into more discrete “transitions;” in nylon 66, there are nuclear resonance effects near 120, 200, 330, and 370°K.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1962.1205916805
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  • 3
    Electronic Resource
    Electronic Resource
    High resolution 1H NMR spectra of 2,2′-biquinoline (1982)
    Chichester : Wiley-Blackwell
    Organic Magnetic Resonance 18 (1982), S. 42-44 
    Details
    ISSN: 0030-4921
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: From analysis and refinement by the LAOCOON III program of the 220 MHz 1H spectrum of 2,2′-biquinoline, recorded as a saturated solution in carbon disulphide, most derived chemical shifts and coupling constants are close to corresponding values in quinoline. However, H-3 is at 1.5 ppm lower field in 2,2′-biquinoline than in quinoline and the ortho-coupling 3J(34) in the heterocyclic ring is 0.5 Hz larger in 2,2′-biquinoline than in quinoline; fairly free rotation about the 2,2′ bond is inferred.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/mrc.1270180110
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  • 4
    Electronic Resource
    Electronic Resource
    High-resolution nuclear magnetic resonance spectra of phenanthrenes-IVFor part III, see Ref. 1. Phenyl derivatives of phenanthrene (1970)
    Chichester : Wiley-Blackwell
    Organic Magnetic Resonance 2 (1970), S. 259-270 
    Details
    ISSN: 0030-4921
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Proton magnetic resonance spectra at 60 MHz are reported for 9, 9′-biphenanthryl, 1-phenylfluoranthene, 9-benzylphenanthrene, 1-, 4- and 9-phenylphenanthrenes and 9-methyl-10-phenylphenanthrene, all in CS2 solution. Approximate values of some of the chemical shifts and coupling constants were extracted from the overlapped and often collapsed AB, ABC ABCD and AA′BB′C (phenyl) spin systems. By comparison with data for phenanthrene itself, estimates have been made for the dihedral angle, θ, between the planes of the phenyl ring and the phenanthrene nucleus in phenylphenanthrenes. These lead, except for 9-phenylphenanthrene for which the angle derived from H(10) by PMR is higher than UV suggests, to plausible values for θ: 90°, 75°, 40° and 45 to 60°, for 4-phenyl, 9-methyl-10-phenyl-, 1- and 9-phenylphenanthrenes, respectively.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/mrc.1270020306
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  • 5
    Electronic Resource
    Electronic Resource
    High-resolution NMR spectra of fluorene and its derivatives: VIFor Part V see Ref. 2. - 1-methylfluorene, truxene and decacyclene (1980)
    Chichester : Wiley-Blackwell
    Organic Magnetic Resonance 14 (1980), S. 272-277 
    Details
    ISSN: 0030-4921
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The overlapping spin systems in the 220 MHz 1H spectra of 1-methylfluorene (1) in carbon disulphide and deuteriated chloroform solutions have been analysed separately and refined by LAOCOON with the aid of methyl- and methylene-decoupled spectra. Ortho-coupling constants in the 6-membered rings are similar to each other and to those in fluorene (4). Solvent and concentration shifts suggest loose pairing of solute molecules. 220 MHz 1H spectra of α-truxene (2) in carbon tetrachloride and deuteriated nitrobenzene, 220 MHz 1H spectra of decacyclene (3) in carbon tetrachloride, and 90 MHz FT 1H spectra of 3 in deuteriated chloroform show steric deshielding; the solvent dependence of shifts also suggests solute pairing in 2. Shifts in 1H decoupled 22.6 MHz 13C spectra of 2 in deuteriated chloroform were assigned with the aid of Cr(acac)3 relaxation agent.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/mrc.1270140410
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  • 6
    Electronic Resource
    Electronic Resource
    Notes on the plenary session on risk management (1994)
    New York, NY [u.a.] : Wiley-Blackwell
    Process Safety Progress 13 (1994), S. 8-8 
    Details
    ISSN: 1066-8527
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/prs.680130108
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  • 7
    Electronic Resource
    Electronic Resource
    A minimization approach for the improvement of cellulose structure models (1968)
    New York : Wiley-Blackwell
    Biopolymers 6 (1968), S. 771-773 
    Details
    ISSN: 0006-3525
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/bip.1968.360060511
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  • 8
    Electronic Resource
    Electronic Resource
    Molecular motion in poly(β-benzyl-L-aspartate) (1971)
    New York : Wiley-Blackwell
    Biopolymers 10 (1971), S. 2039-2048 
    Details
    ISSN: 0006-3525
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: As the temperature of solid poly(β-benzyl-L-aspartate) (PBLA), (CO.NH.CH.-CH2COOCH2C6H5)n, in the α-helieal form is raised from -150 °C, tlie line width and second moment of the proton magnetic resonance (PMR) signal decrease in stages until the conformational transition to the ω-helix occurs at about 90 °C. A similar temperature dependence of the PMR parameters is observed as the transformed polymer is cooled. Below -100°C (where the lattice is presumed to be rigid), the measured second moments are 9.5 Oe2 and 10.7 Oe2 for the α and ω forms, respectively. Second moments, calculated from the Van Vleck formula for the rigid lattice and also estimated for possible motional cases in which the polymer is taken to be in the ω form, are compared with the PMH data. By combination with the results of X-ray diffraction and infrared spectroscopic measurements, a tentative explanation can be made of the types of motion occurring in PBLA.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/bip.360101019
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  • 9
    Electronic Resource
    Electronic Resource
    Crystalline modifications of cellulose. Part III. The derivation and preliminary study of possible crystal structures (1958)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 32 (1958), S. 371-394 
    Details
    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Scale models are described for a stereochemical study of the cellulose chain assuming standard armchair β-glucose residues crystallizing in space-group P21. Infrared evidence about the hydrogen bonding and intensity data for the strongest equatorial and meridional x-ray reflections are utilized in assessing the validity of many models. The structures published by Meyer and Misch and by other workers do not comply with the criteria thus set up. Some fully hydrogen bonded structures, which are likely to form the basis of the most highly ordered regions in cellulose I and II, are discussed.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1958.1203212508
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  • 10
    Electronic Resource
    Electronic Resource
    Crystallization of experimental bioactive glass compositions (1996)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Biomedical Materials Research 32 (1996), S. 119-124 
    Details
    ISSN: 0021-9304
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine , Technology
    Notes: Crystallization kinetics studies for six experimental glass formulations in the system Na2O-CaO-SiO2-P2O5 synthesized by wet chemistry were conducted by means of differential thermal analysis. These glasses had CaO/P2O5 and SiO2/(CaO + Na2O) ratios ranging from 8.74-3.38 and 0.92-3.03, respectively. Samples of each glass (n = 30 were heated from 23 to 1250°C under N2 atmosphere at heating rates ranging from 10 to 50°C/min. Glass-ceramics were obtained after heat treating the initial glasses at temperatures determined from their DTA exotherms. The activation energy of crystallization for each glass composition was calculated from an expression-relating log-heating rate and the reciprocal of the exothermic peak temperature. The compositions of the six glasses were significantly different (p = 0.05). The activation energy of crystallization (Q) values ranged from 196 to 782 kJ/mole. A correlation was obtained between Q and CaO/P2O5 and between Q and the Young's modulus (p 〈 0.001). Two of the six glasses exhibited bulk crystallization. X-ray diffraction studies showed that four of the six glasses exhibited different proportions of crystalline phases following heat treatment. These phases were wollastonite (CaSiO3), Na2CaSi3O9, combeite [Na4Ca3SI6O16(OH)2], and some unidentifiable phases. Two of the six bioceramic materials had a mixture of unknown crystalline phases. © 1996 John Wiley & Sons, Inc.
    Additional Material: 13 Ill.
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