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  • 1
    Electronic Resource
    Electronic Resource
    Secondary ion mass spectrometry round-robin study of impurity analysis in gallium arsenide using uniformly-doped standard gallium arsenide specimens (1994)
    Chichester [u.a.] : Wiley-Blackwell
    Surface and Interface Analysis 21 (1994), S. 23-31 
    Details
    ISSN: 0142-2421
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: This paper reports results of the second SIMS round-robin study on GaAs impurity analysis in which 16 laboratories participated. Three different types of SIMS instruments, including Cameca IMS-3F or IMS-4F, Atomika ADIDA-3000 and Hitachi IMA-3, were used for this study. The specimens were cut from identical multielement-doped GaAs crystals and distributed as common standards for the quantitative impurity analyses. The interlaboratory deviations in quatitative results based on the common standards were found to be 10-20%, except for some low-concentration specimens and the results for zinc. This was approximately half of the corresponding results produced from standard specimens provided by the laboratories themselves. The interlaboratory deviations of relative ion intensity between impurity and matrix were 〈50% for those laboratories employing instruments of the same type, except for low-concentration specimens. These results show that quantitative analysis to an accuracy of 50% can be performed without standard specimens by utilizing relative sensitivity factors for each type of instrument.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/sia.740210104
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  • 2
    Electronic Resource
    Electronic Resource
    Restricted rotation involving the tetrahedral carbon: XXIIIFor Part XXII. see Ref. 1. - comparison of barriers to rotation of 9-(2-isopropylphenyl) fluorene obtained by 1H DNMR, 13C DNMR, double resonance and kinetic measurements (1979)
    Chichester : Wiley-Blackwell
    Organic Magnetic Resonance 12 (1979), S. 702-707 
    Details
    ISSN: 0030-4921
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Rates of rotation about the C-9-C-ar bond of 9-(2-isopropylphenyl) fluorene were measured by 1H DNMR, 13C DNMR, double resonance, and a kinetic method. The kinetic data obtained by these methods were critically examined. The DNMR methods afforded satisfactory results if rate data obtained by total line shape analyses of complicated signals with couplings were used, and those derived from simple patterns were abandoned. Agreement among the data yielded by the four different methods was excellent, provided that the data which might contain dubiously large errors were excluded.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/mrc.1270121211
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  • 3
    Electronic Resource
    Electronic Resource
    Molecular aggregation of PEEK with PES blends and the block copolymers composed of PEEK and PES components (1989)
    Weinheim : Wiley-Blackwell
    Angewandte Makromolekulare Chemie 173 (1989), S. 163-181 
    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: Röntgendiffraktometrische Untersuchungen und DSC-Messungen an Blend-Filmen, die aus Lösungen von PEEK und PES hergestellt wurden, zeigen eine Phasenseparation bei den Filmen, die bei 340°C hergestellt wurden. Das Kristallisationsverhalten von Filmen, die bei 340°C hergestellt, anschließend abgeschreckt und bei 180°C getempert wurden, ist identisch mit dem von PEEK. Filme, die bei 300°C hergestellt wurden, kristallisierten erst durch Tempern bei 250°C. Blockcopolymere, die aus Oligomeren von PEEK und PES erhalten wurden, unterscheiden sich in dieser Hinsicht von Blends der gleichen Zusammensetzung. Die Glastemperatur von Copolymeren mit einem PEEK-Gehalt von mehr als 50% liegt höher als die von PEEK selbst, während der Schmelzpunkt dieser Copolymeren niedriger als der von PEEK ist.
    Notes: Polymer blends of PEEK with PES were prepared by the solution blending method. Copolymers composed of PEEK and PES components were synthesized from these oligomers. The formation conditions exerted an influence over the molecular aggregation and the crystallization behaviors of the blend films and block copolymers which were examined by X-ray diffractometry and DSC analysis. As a result, phase-separation in the blend films was found when the formation temperature was high. The blend films formed at 340°C, quenched and annealed at 180°C, exhibited the same crystallization behavior as those of PEEK. In the case of the blend films formed at 300°C, the annealing of the films at 250°C was required to crystallize the blend films. The Tg of a copolymer with a PEEK component content of more than 50% tends to shift toward a higher temperature than the Tg of PEEK itself, and the Tm of the copolymer toward a lower temperature than that of PEEK ist.
    Additional Material: 16 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/apmc.1989.051730113
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  • 4
    Electronic Resource
    Electronic Resource
    1H-, 13C-, and 113Cd-nmr study of the Cd(II) complex of a blocked peptide, Z-Cys-Ala-Pro-His-OMe, in organic solvents (1995)
    New York : Wiley-Blackwell
    Biopolymers 35 (1995), S. 319-329 
    Details
    ISSN: 0006-3525
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The Cd(II) complex of a peptide, Z-Cys-Ala-Pro-His-OMe was prepared and characterized by absorption, CD, 1H-, 13C-, and 113Cd-nmr, and nuclear Overhauser effect spectroscopy (NOESY) spectra to show the coordination of cysteine thiolate and histidine imizazole to Cd(II) ion. The NOESY spectra in dimethyl formamide showed that the cysteine residue was in proximity to the histidine residue. These results reveal the dictation of Z-Cys-Ala-Pro-His-OMe to Cd(II) ion in solution. Temperature-dependent dissociation equilibrium of histidine imidazole in solution was observed in this complex. Structural features of the chelating peptide are discussed. © 1995 John Wiley & Sons, Inc.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/bip.360350307
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  • 5
    Electronic Resource
    Electronic Resource
    Thermal and viscoelastic behavior of polyetheretherketone/polyethersulfone blends (1989)
    Weinheim : Wiley-Blackwell
    Angewandte Makromolekulare Chemie 171 (1989), S. 119-130 
    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: Die aus Lösung hergestellten Polymermischungen zeigen den Typus der vollmischbaren Polymerlegierungen. Proben, die durch Formpressen der Polymermischungen unterhalb des Schmelzpunkts von Polyetheretherketon (PEEK) erhallten wurden, zeigen ein für mischbare Polymerlegierungen typisches viskoelastisches Verhalten. Hingegen zeigt sich bei Mischungen, die oberhalb des Schmelzpunktes von PEEK verpreßt wurden, im dynamisch-viskoelastischen Verhalten eine Phasentrennung.
    Notes: The polymer blends obtained by the solution blending method show a type of compatible polymer blends. The samples obtained by compression molding the polymer blends below the melting point of the polyetheretherketon (PEEK) exhibit dynamic viscoelastic behavior characteristic of compatible polymer blends, but those by compression molding above the melting point of the PEEK show a phase separation in dynamic viscoelastic behavior.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/apmc.1989.051710109
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  • 6
    Electronic Resource
    Electronic Resource
    Photochemische Reaktionen 115. Mitteilung [1]. Zur Photochemie konjugierter γ,δ-Epoxyenone: Der Einfluss eines Hydroxylsubstituenten in ∊-StellungMit den besten Wünschen Herrn Dr. Willy G. Stoll zum 70. Geburtstag zugeeignet (1980)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 63 (1980), S. 2230-2257 
    Details
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Photochemistry of Conjugated γ,δ-Epoxyenones: The Influence of a Hydroxy Substituent in ∊-PositionOn 1n, π*- or 1π,π*-excitation (λ ≥ 347 or λ=254 nm), the ε-hydroxy-γ;,δ-epoxyenone 8 undergoes fission of the C(γ)—O bond followed by the cleavage of the C(δ)-C(ε) bond. This hitherto unknown sequence of reactions is evidenced by the structure determination of the new type products 10-17 and 25, including a synthetic proof for 12 and the X-ray analysis of 11 (X-ray data: triclinic P1; a=7,386(2), b=8,904(4), c=9,684(5)Å; α=82,29(4)°, β=74,46(3)°, γ=82,29(3)°; Z=2).The selective 1π,π*-excitation also induces competitive C(γ)-C(δ) bond cleavage to yield the bicyclic acetal 18 and a ketonium-ylide intermediate a, which photochemically forms a carbene b giving the allene 19 and the cyclopropene 20.On 1n,π*-excitation of the acetate 9 the initial C(γ)-O bond fission is, in contrast to the behaviour of the corresponding alcohol 8, followed by a 1,2-methyl shift affording (E/Z)-28 or by a cyclization-autoxidation process yielding the lactone 29.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/hlca.19800630813
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  • 7
    Electronic Resource
    Electronic Resource
    Photochemische Reaktionen 130. Mitteilung129. Mitteilung s. [1].. Zur Photochemie von 5,6-Epoxy-1,3-dienen: Der Einfluss eines 7-Hydroxysubstituenten auf die CarbenbildungTeil II; Teil I s. [2]. (1983)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 66 (1983), S. 2236-2251 
    Details
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Photochemistry of 5,6-Epoxy-1,3-dienes: Influence of a 7-Hydroxy Substituent on the Carbene FormationOn singlet excitation (λ=254 nm) in MeCN the hydroxy-epoxydiene (E)-4 undergoes photocleavage to the carbene intermediates d and e as main processes. The carbene d, showing behaviour typical of vinyl carbenes, undergoes addition to the adjacent double bond furnishing the cyclopropenes 5A + B. The carbene e, however, undergoes an insertion reaction into the neighbouring carbinol C,H-bond leading to the enol intermediate 21, which gives rise to the compounds 6A + B and 7A + B. To a lesser extent the products 8A + B are formed via another enol intermediate (32). On photolysis of (E)-4 in MeOH instead of MeCN the enol intermediates 21 and 32 undergo rapid tautomerisation to the ketones 9A + B (main products) and 11.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/hlca.19830660735
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  • 8
    Electronic Resource
    Electronic Resource
    Norbornadiene(bipyridyl)molybdenum(II) Complexes: Synthesis, Structure and Reactivity of [Mo(CO)(C7H8)(C10H6R2N2)X2] (X = I, Br)Dedicated to Professor Dr. Helmut Werner on the occasion of his birthday. (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 1007-1013 
    Details
    ISSN: 0009-2940
    Keywords: Tetracarbonyl(norbornadiene)molybdenum(0) ; Oxidative addition of I2 ; Dihalogeno(bipyridyl)molybdenum(II) complexes ; 7-Coordinated complexes ; Neutral and cationic molybdenum(II) complexes ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The reaction of [Mo(CO)4(C7H8)] (1) with I2 gave the norbornadienemolybdenum(II) complex [Mo(CO)2(C7H8)I2]n≥1 (2), which existed in an equilibrium of two isomeric forms. In acetonitrile, 2 reversibly formed the adduct [Mo(CO)2-(C7H8)(NCCH3)I2] (3), whereas on treatment with 2,2′-bipyridine or 4,4′-di-2,2′-tBu-bipyridine, it gave stable 7-coordinated molybdenum(II) complexes, [Mo(CO)(C7H8)-(C10H8N2)I2] (4) and [Mo(CO)(C7H8)(C10H6tBu2N2)I2] (5), in good yield. In similar reactions, the related dibromomolybdenum compounds [Mo(CO)(C7H8)(C10H8N2)Br2] (6) and [Mo-(CO)(C7H8)(C10H6tBu2N2)Br2] (7) were prepared by oxidation of 1 with two equivalents of CuBr2. The X-ray structural analysis of 6 reveals that the geometry around the molybdenum atom is nearly perfectly pentagonal bipyramidal, with the CO and one of the bipyridyl rings perpendicular to the plane formed by the other ligands. The compounds 5 and 6 react with AgSbF6 by halogen abstraction to give cationic complexes, {[Mo(CO)(C7H8)(C10H8N2)Br]SbF6}n≥1 (8) and {[Mo(CO)(C7H8)(C10H6tBu2N2)I]SbF6}n≥1 (9): In acetone, 8 and 9 reversibly formed the adducts [Mo(CO)(C7H8)(C10H8N2)(acetone)Br]SbF6 (8′) and [Mo(CO)(C7H8)(C10H6tBu2N2)(acetone)I]SbF6 (9′); while on treatment with PMe3, the stable monomeric complexes, [Mo(CO)(C7H8)(C10H8N2)(PMe3)Br]SbF6 (10) and [Mo(CO)(C7H8)(C10H6tBu2N2)(PMe3)I]SbF6 (11), were isolated in almost quantitative yield. In the presence of KBr, compound 8′ reverted to the dibromo complex 6, whereas 9′ reacted to produce a 1:1:2 mixture of 5, 7 and the bromo(iodo) complex [Mo(CO)(C7H8)(C10H6tBu2N2)BrI] (12). The same mixture is available from the reaction of 5 with one equivalent of 7.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951281008
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  • 9
    Electronic Resource
    Electronic Resource
    Novel Aromatic Azopolymers with Regularly Interposed Tellurium Atoms in the Backbone (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 703-709 
    Details
    ISSN: 0009-2940
    Keywords: Copolymers ; Electrical conductivity ; Azo compounds ; Tellurides, organo ; Telluration ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Previously unknown alt-copoly(telluro-1,4-phenylene/azo-1,4-phenylene) and related polymers were synthesized by several different approaches, which include a) reductive polymerization of bis(4-nitrophenyl) tellurides with zinc; b) oxidative polymerization of bis(4-aminophenyl) telluride using a CuI/CuII redox system as catalyst under oxygen; c) electrochemical polymerization of bis(4-amino-3,5-dimethylphenyl) telluride; d) condensation polymerization of 1,4-dinitrosobenzene with bis(4-aminophenyl) telluride Te, Te-dichloride, and e) condensation polymerization of bis(4-nitrophenyl) telluride with bis(4-aminophenyl) telluride in the presence of sodium hydroxide. The polymers obtained were characterized by elemental analysis, 13C-CPMAS NMR, IR and UV-vis spectroscopy, GPC, and inherent viscosity measurements, and their properties were examined, particularly their electrical conductivity. The electrical conductivities of the new polymers 9b c, and 10 were shown to increase from below 10-7 up to 10-5 ∽ 10-2 S cm-1 upon bromine doping in spite of their formally interrupted conjugation structure.
    Additional Material: 2 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951280708
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  • 10
    Electronic Resource
    Electronic Resource
    Synthesis of hexacyclo[5.4.1.02,6.03,10.04,8.09,12]dodecane-5,11-dione and its conversion to di-, tri-, and tetranitro-1,3-bishomopentaprismanes (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 3782-3800 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Synthese von Hexacyclo[5.4.1.02,6.03,10.04,8.09,12]dodecan-5,11-dion und seine Umwandlung in Di-, Tri- und Tetranitro-1,3-bishomoprismaneSulfenylierung des Dianions von Dimethyl-tetracyclo[7.2.1.04,11.06,10]dodeca-2,7-dien-5,12-dicarboxylat (9) mit Dimethyldisulfid ergab das exo,exo-Bis(methylthio)-Derivat 10a. Nachfolgende Hydrolyse und oxidative Decarboxylierung führte zu Tetracyclo[7.2.1.04,11.06,10]-dodeca-2,7-dien-5,12-dion (4), ein wichtiges Zwischenprodukt. Es wurde in das Bisketal 11 übergeführt und dieses zum doppelt funktionalisierten 1,3-Bishomopentaprismen 12 photolysiert. Nachfolgende saure Hydrolyse ergab die Titelverbindung 5, woraus drei Dinitro-(14 - 16), zwei Trinitro- (20, 21) und ein Tetranitro-Derivat (22) erhalten wurden. Die Konfigurationszuordnung der ersten vier Produkte erfolgte 1H-NMR-spektroskopisch und durch Röntgenstrukturanalyse von 21. Die Stereochemie der Nitro-substituierten Käfigmoleküle wird aufgrund ihrer Bildung und ihrer Dichte diskutiert, die in vielen Fällen erhöht ist. Auch von Tetranitro-bishomopentaprisman 22 wurden die strukturellen Eigenschaften durch eine Röntgenstrukturanalyse erhellt.
    Notes: Sulfenylation of the dianion of dimethyl tetracyclo[7.2.1.04,11.06,10]dodeca-2,7-diene-5,12-dicarboxylate (9) with dimethyl disulfide delivered the exo,exo-bis(methylthio) derivative 10a. Subsequent saponification and oxidative decarboxylation resulted in transformation to tetracyclo[7.2.1.04,11.06,10]dodeca-2,7-diene-5,12-dione (4). Upon photolysis of the bisketal 11 of this pivotal intermediate, arrival at the doubly functionalized 1,3-bishomopentaprismane 12 was achieved. Following acidic hydrolysis to give the title compound 5, elaboration of three dinitro (14 - 16), two trinitro (20, 21), and a tetranitro derivative (22) was accomplished. The configurational assignment to the first four products was achieved by means of 1H NMR spectroscopy and an X-ray crystal structure analysis of 21. The stereochemistries of the nitro-substituted cage molecules are discussed in terms of the mechanism of their formation and their densities, many of which are markedly enhanced. The structural features of the tetranitro-bishomopentaprismane 22 have also been elucidated by X-ray methods.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19861191222
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