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Transition-metal complexes with sulfur ligands. 62. Hydrogen evolution upon reaction of protons with sulfur-coordinated iron(II) complexes. Investigation of the proton, hydrogen and hydride interactions with iron 1,2-benzenedithiolate complexes

Dieter Sellmann、Michael Geck、Matthias Moll1991-07-01Journal of the American Chemical Society

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTTransition-metal complexes with sulfur ligands. 62. Hydrogen evolution upon reaction of protons with sulfur-coordinated iron(II) complexes. Investigation of the proton, hydrogen and hydride interactions with iron 1,2-benzenedithiolate complexesDieter Sellmann, Michael Geck,…

Metal complexes synthesis and propertiesCorrosion Behavior and InhibitionMetalloenzymes and iron-sulfur proteins

A New Approach to the Theory of the Compression of Fiber Assemblies

Takashi Komori、Motoyoshi Itoh1991-07-01Textile Research Journal

A formula is presented for the mechanics of a fiber mass under extensive compres sion. The mass is treated as the assembly of the fiber elements whose individual bending behaviors are combined into the overall response of the mass. The stress-strain relation and Poisson's ratio are expressed in terms of the strain-dep…

Mechanical Behavior of CompositesTextile materials and evaluationsMechanical Engineering and Vibrations Research

Chemical Characterization of Si‐Al‐C‐O Precursor and Its Pyrolysis

Florence Babonneau、Gian Domenico Sorarù、Kevin J. Thorne 等 4 位作者1991-07-01Journal of the American Ceramic Society

Polycarbosilane was modified by reaction with an aluminum alkoxide to get a precursor for Si‐Al‐C‐O ceramics. The precursor was essentially characterized by magic‐angle spinning nuclear magnetic resonance ( 29 Si, 27 Al, and 13 C) and appeared as a dispersion of Al(OH) 3 ‐based particles in a polycarbosilane chain mat…

Advanced ceramic materials synthesisAluminum Alloys Composites PropertiesBoron and Carbon Nanomaterials Research

The role of 90° domain wall displacements in forming physical properties of perovskite ferroelectric ceramics

E. I. Bondarenko、V. Yu. Topolov、A. V. Turik1991-07-01Ferroelectrics Letters Section

A proposed model which takes into account an elastic interaction between a polydomain grain and a surrounding ceramic matrix under weak external mechanical stresses has been used for evaluating a contribution from 90° domain wall displacements to piezoelectric and elastic constants of the perovskite ferroelectric cera…

Ferroelectric and Piezoelectric MaterialsComposite Material MechanicsDielectric materials and actuators

Dynamic high-pressure properties of AlN ceramic as determined by flyer plate impact

Z. Rosenberg、N. S. Brar、Stephan Bless1991-07-01Journal of Applied Physics

The dynamic properties of hot-pressed aluminum nitride ceramics were determined in a series of plate impact experiments using longitudinal and transverse in-material manganin gauges. The Hugoniot curve for hot pressed specimens was determined in the range of 0–190 kbar with a value of 94±2 kbar for the Hugoniot elasti…

Advanced ceramic materials synthesisMetal and Thin Film MechanicsAcoustic Wave Resonator Technologies

Nematic director orientation in a liquid-crystal-dispersed polymer: A deuterium nuclear-magnetic-resonance approach

Ralf Stannarius、G. P. Crawford、Ling‐Chu Chien 等 4 位作者1991-07-01Journal of Applied Physics

The nuclear-magnetic-resonance (NMR) technique is employed to liquid-crystal-dispersed-polymer (LCDP) systems. Deuterium NMR is used to determine director distributions in LCDP cells in the presence of a magnetic field. The samples consist of a nematic liquid crystal mixed with small percentages of a monomer that is p…

Liquid Crystal Research AdvancementsNonlinear Dynamics and Pattern FormationMolecular spectroscopy and chirality

The dynamic properties, temperature transitions, and thermal stability of poly (etherether ketone)‐thermotropic liquid crystalline polymer blends

Atul M. Mehta、А. I. Isayev1991-07-01Polymer Engineering and Science

Abstract Differential scanning calorimetry, dynamic mechanical measurements, and thermal gravimetric analysis techniques have been used to thermally characterize blends of poly(etherether ketone)‐thermotropic liquid crystalline polymer (LCP) based on hydroxybenzoic and hydroxynaphthoic acid (HBA/HNA). Based upon diffe…

Liquid Crystal Research AdvancementsPolymer Nanocomposites and PropertiesRheology and Fluid Dynamics Studies

Weathering Environments and Occurrence of Imogolite/Allophane in Selected Andisols and Spodosols

F. C. Ugolini、Randy A. Dahlgren1991-07-01Soil Science Society of America Journal

Abstract Imogolite and allophane have been found in various soil environments, but most commonly occur in Spodosols and Andisols. Controversy exists regarding the origin of these short‐range‐order aluminosilicates, especially in Spodosols. The proto‐imogolite theory suggests that imogolite forms in the surficial miner…

Soil and Unsaturated FlowClay minerals and soil interactionsTherapeutic Uses of Natural Elements

Pressure dependence of the structural properties of α-quartz near the amorphous transition

James R. Chelikowsky、N. Troullier、José Luı́s Martins 等 4 位作者1991-07-01Physical review. B, Condensed matter

Silicon dioxide exists in a number of structures. The lowest-energy structure is that of \ensuremath{\alpha}-quartz. We predict the structural properties of \ensuremath{\alpha}-quartz as a function of pressure via total-energy calculations. The calculations are based on recently developed pseudopotentials constructed…

High-pressure geophysics and materialsGlass properties and applicationsSeismic Waves and Analysis

Observation of Propagation Speed of Conductive Front in Electrochemical Doping Process of Polypyrrole Films

Yoshihiko Tezuka、Shigeru Ohyama、Tadahiro Ishii 等 4 位作者1991-07-01Bulletin of the Chemical Society of Japan

Abstract According to the propagation theory of a conductive zone for the electrochemical doping process of conducting polymer films, an oxidized conductive zone works as an electrode for oxidizing the reduced non-conductive region and is propagated throughout the film under charge transfer control. This theory was ve…

Advanced Sensor and Energy Harvesting MaterialsConducting polymers and applicationsAnalytical Chemistry and Sensors

THE GENUSCRATICULA

David G. Mann、Alan J. Stickle1991-07-01Diatom Research

The history and characteristics of the genus Craticula are reviewed, to justify its separation from Navicula and from the Naviculaceae. Members of the genus have previously been put in Navicula sect. Orthostichae; they include such species as those formerly known as Navicula cuspidata, N. ambigua, N. perrotettii and N…

Analytical chemistry methods developmentAquatic Ecosystems and Phytoplankton DynamicsDiatoms and Algae Research

The microstructure of polydisperse, charged colloidal suspensions by light and neutron scattering

Norman J. Wagner、R. Krause、Adrian R. Rennie 等 5 位作者1991-07-01The Journal of Chemical Physics

Structure measurements of a suspension of charged polystyrene spheres with significant polydispersity (16%) are reported for a wide range of particle and added salt concentrations and scattering wave vector. Small angle neutron scattering yielded the structure factors of concentrated samples that have had extensive rh…

Material Dynamics and PropertiesRheology and Fluid Dynamics StudiesElectrostatics and Colloid Interactions

Influence of potential on metal-adsorbate structure: solvent-independent nature of infrared spectra for platinum(111) carbon monoxide

Si Chung Chang、Xudong Jiang、Joseph D. Roth 等 4 位作者1991-07-01The Journal of Physical Chemistry

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTInfluence of potential on metal-adsorbate structure: solvent-independent nature of infrared spectra for platinum(111) carbon monoxideSi Chung Chang, Xudong Jiang, Joseph D. Roth, and Michael J. WeaverCite this: J. Phys. Chem. 1991, 95, 14, 5378–5382Publication Date (Print):J…

Catalytic Processes in Materials ScienceCatalysis and Oxidation ReactionsElectron and X-Ray Spectroscopy Techniques

p-Aminobenzoate biosynthesis in Escherichia coli. Purification of aminodeoxychorismate lyase and cloning of pabC

Jacalyn M. Green、Brian P. Nichols1991-07-01Journal of Biological Chemistry

p-Aminobenzoate, a component of the vitamin folate, is one of seven compounds derived from the aromatic precursor chorismate in Escherichia coli. Historically the gene products of pabA and pabB were assumed to be sufficient for de novo p-aminobenzoate biosynthesis. Recent studies, however, have shown that these protei…

Microbial Metabolic Engineering and BioproductionMetabolism and Genetic DisordersEnzyme Structure and Function

Influence of Stress Ratio on the Elevated‐Temperature Fatigue of a Silicon Carbide Fiber‐Reinforced Silicon Nitride Composite

John W. Holmes1991-07-01Journal of the American Ceramic Society

The influence of stress ratio on the tensile fatigue behavior of a unidirectional SiC‐fiber/Si 3 N 4 ‐matrix composite was investigated at 1200°C. Tensile stress ratios of 0.1, 0.3, and 0.5 were examined. Fatigue testing was conducted in air, at a sinusoidal loading frequency of 10 Hz. For peak fatigue stresses below…

Advanced ceramic materials synthesisMechanical Behavior of CompositesFire effects on concrete materials

Reactions of iodoethane, iodopropane, 2-iodopropane, chloroiodomethane adsorbed on silver(111)

Xiaojing Zhou、John White1991-07-01The Journal of Physical Chemistry

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTReactions of iodoethane, iodopropane, 2-iodopropane, chloroiodomethane adsorbed on silver(111)X. L. Zhou and J. M. WhiteCite this: J. Phys. Chem. 1991, 95, 14, 5575–5580Publication Date (Print):July 1, 1991Publication History Published online1 May 2002Published inissue 1 Jul…

Electronic and Structural Properties of Oxides

FerroelectricSr0.60Ba0.40Nb2O6thin films by the sol-gel process: Electrical and optical properties

Yuhuan Xu、Ching Jih Chen、Ren Xu 等 4 位作者1991-07-01Physical review. B, Condensed matter

Transparent ferroelectric strontium barium niobate (SBN) thin films were made on fused silica, silicon, and GaAs substrates by the sol-gel process. The microstructure of these thin films was studied. Preferentially oriented SBN thin films on fused silica substrates can be obtained by applying a dc electric field durin…

Ferroelectric and Piezoelectric MaterialsPhotorefractive and Nonlinear OpticsMicrowave Dielectric Ceramics Synthesis

Luminescence from the chair and cube isomers of tetrakis[(triphenylphosphine)iodosilver]

Maher M. Henary、Jeffrey I. Zink1991-07-01Inorganic Chemistry

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTLuminescence from the chair and cube isomers of tetrakis[(triphenylphosphine)iodosilver]Maher Henary and Jeffrey I. ZinkCite this: Inorg. Chem. 1991, 30, 15, 3111–3112Publication Date (Print):July 1, 1991Publication History Published online1 May 2002Published inissue 1 July…

Lanthanide and Transition Metal Complexes

An X‐ray photoelectron spectroscopic investigation of the selectivity of hydroxyl derivatization reactions

Ashutosh Chilkoti、Buddy D. Ratner1991-07-01Surface and Interface Analysis

Abstract The Selectivity of trifluoroacetic anhydride (TFAA), used for the vapor‐phase derivatization of hydroxyl groups in multifunctional oxygen‐containing polymeric surfaces, has been investigated by XPS studies on model epoxides systems. The reactivity of TFAA towards epoxides observed here is discussed in the con…

Analytical Chemistry and SensorsElectron and X-Ray Spectroscopy TechniquesSilicone and Siloxane Chemistry

Analysis and nucleotide sequence of the genes encoding the surface‐layer glycoproteins of the hyperthermophilic methanogens Methanothermus fervidus and Methanothermus sociabilis

Günther Bröckl、Michael Behr、Stefan Fabry 等 7 位作者1991-07-01European Journal of Biochemistry

The genes (slgA) encoding the surface-layer glycoproteins of the hyperthermophilic methanogens Methano-thermus pervidus and Methanothermus sociabilis were cloned and sequenced. The nucleotide sequences of these genes differ at only nine positions, resulting in three amino acid differences. In both organisms, the trans…

Bacterial Genetics and BiotechnologyEnzyme Structure and FunctionPorphyrin Metabolism and Disorders