Vicente Rubio、Javier Lizardi Cervera、Carol J. Lusty 等 5 位作者1991-01-01Biochemistry
The large subunit of Escherichia coli carbamoyl phosphate synthetase (a polypeptide of 117.7 kDa that consists of two homologous halves) is responsible for carbamoyl phosphate synthesis from NH3 and for the binding of the allosteric activators ornithine and IMP and of the inhibitor UMP. Elastase, trypsin, and chymotry…
Computational Drug Discovery MethodsEnzyme Structure and FunctionBiochemical and Molecular Research
Thomas P. Gall、Edward J. Krämer1991-01-01Polymer
The diffusion of deuterated toluene (d-toluene) from the vapour into glassy polystyrene has been studied using forward recoil spectrometry (FRES) over a range of temperatures (20–35°C) and d-toluene activities (0.10 to 0.35). At the highest d-toluene activity a Case II diffusion front is observed to form and propagate…
Polymer crystallization and propertiesPhase Equilibria and ThermodynamicsMaterial Dynamics and Properties
R. Franz、H. Werheit1991-01-01AIP conference proceedings
The Jahn‐Teller effect is shown to be the fundamental reason of the general distortion of the B12 icosahedra in molecular and crystalline structures. In consequence of the Jahn‐Teller effect the degeneracy of the upermost partly occupied energy level is lifted, and occupied and unoccupied states become separated. This…
Boron and Carbon Nanomaterials ResearchBoron Compounds in ChemistrySuperconductivity in MgB2 and Alloys
A.M. Bruning、D.G. Kasture、F. J. Campbell 等 4 位作者1991-01-01IEEE Transactions on Electrical Insulation
Calculations and experiments applying voltage to a test cell simulating a high-resistance conducting path in series with a cavity in polyethylene are discussed. These experiments generated chemical changes on the surface wall of the cavities for both subcorona currents (currents produced by voltage below critical ince…
High voltage insulation and dielectric phenomenaLightning and Electromagnetic PhenomenaPower Transformer Diagnostics and Insulation
Adrian J. Moore、Martin R. Bryce、David Ando 等 4 位作者1991-01-01Journal of the Chemical Society Chemical Communications
The efficient synthesis of three new vinylogous derivatives 6–8 of bis(ethylenedithio)tetrathiafulvalene (BEDT–TTF) is described; cyclic voltammetry establishes that the new donors have significantly lower solution oxidation potentials than that of BEDT–TTF, and the single crystal X-ray structure of compound 8 is desc…
Magnetism in coordination complexesOrganic and Molecular Conductors ResearchSolid-state spectroscopy and crystallography
Élie Protopopoff、Philippe Marcus1991-01-01Journal de Chimie Physique
The effects of chemisorbed sulphur on the hydrogen adsorption and evolution in aqueous acid solution are reviewed for well-controlled surfaces of platinum, nickel, iron and silver. The hydrogen underpotential adsorption (HUA) on platinum is poisoned by adsorbed sulphur. The hydrogen evolution reaction (HER) on Pt, Ni,…
Corrosion Behavior and InhibitionMolecular Junctions and NanostructuresElectrodeposition and Electroless Coatings
Mohan Ram、Joseph T. Hupp1991-01-01Inorganic Chemistry
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTGeneralized synthesis of cis- and trans-dioxorhenium(V) (bi)pyridyl complexesM. S. Ram and Joseph T. HuppCite this: Inorg. Chem. 1991, 30, 1, 130–133Publication Date (Print):January 1, 1991Publication History Published online1 May 2002Published inissue 1 January 1991https://…
Radioactive element chemistry and processingPolyoxometalates: Synthesis and ApplicationsSynthetic Organic Chemistry Methods
J.L. Sessler、Michael Cyr、Anthony K. Burrell1991-01-01Synlett
All articles of this category Sapphyrin, so called due to its intense blue-green color, is a 22 π-electron pentapyrrolic molecule known for over 20 years. This macrocycle can now be prepared in good yield and is becoming the subject of serious current study. Although planar and aromatic, the larger size of this "expan…
Porphyrin and Phthalocyanine Chemistry
Masayuki Kuzuya、Akihiro Noguchi、Hideki Ito 等 5 位作者1991-01-01Journal of Polymer Science Part A Polymer Chemistry
Abstract Plasma‐induced polystyrene radicals were first studied by electron spin resonance (ESR). The room temperature ESR spectrum was compared with those obtained by γ‐irradiation, UV‐irradiation, and mechanical fracture. It was found that even less than a few seconds of plasma‐irradiation gave rise to a large amoun…
GaN-based semiconductor devices and materialsSurface Modification and SuperhydrophobicityOrganic Light-Emitting Diodes Research
Renate Foerch、J. Izawa、G. Spears1991-01-01Journal of Adhesion Science and Technology
The effects of remote nitrogen plasma, remote oxygen plasma, and corona discharge treatments on linear low-density polyethylene were studied with regard to the chemical and physical surface modification, depth of modification, and surface stability. An attempt was made to correlate the type and the extent of modificat…
Surface Modification and SuperhydrophobicityRecycling and Waste Management TechniquesElectron and X-Ray Spectroscopy Techniques
Robert W. Gensemer1991-01-01Limnology and Oceanography
The effects of pH and Al on the acidophilic diatom Asterionella ralfsii var. americana Körn. were examined in axenic batch cultures. Experiments were performed under conditions of both high (pH 5) and low (pH 6) Al solubility over a range of concentrations from 0 to 30 µ mol liter −1 total Al. Growth rates were analyz…
Diatoms and Algae Research
G. Bodor1991-01-01Ellis Horwood eBooks
Part 1 Characterization of polymer molecules: chemical composition of polymeric chains molecular mass of polymers molecular mass distribution in polymers - general characterization of the distribution curve. Part 2 Arrangement of polymers and polymer morphology: the two-phase structure of polymers - crystallinity meth…
Material Properties and ApplicationsAdsorption, diffusion, and thermodynamic properties of materialsPolymer Science and Applications
Adrian J. Moore、Martin R. Bryce1991-01-01Synthesis
All articles of this category 2-Dimethoxyphosphoryl-5,6-dihydro-1,3-dithiolo[4,5- b ][1,4]-2-dithiin ( 8 ) and 2-triphenylphosphonio-5,6-dihydro-1,3-dithiolo-[4,5- b ][1,4]dithiin tetrafluoroborate ( 9 ) have been obtained in four steps from 4,5-ethylenedithio-1,3-dithiole-2-thione ( 4 ) (ca. 75% overall yield). Depro…
Organic and Molecular Conductors ResearchSynthesis and Catalytic ReactionsSynthesis and Reactivity of Sulfur-Containing Compounds
HIROO FUKUYO、Hsin-Hua Tsai、T. Oyama 等 4 位作者1991-01-01ISIJ International
Elevated temperature (1 023 to 1 193 K) tensile properties are described for a fine (6 μm) and coarse (100 μm) grained ultrahigh carbon (1.25 %) steel containing 10 % aluminum. The coarse-grained steel exhibits Class I solid solution alloy behavior wherein a stress exponent of three is noted. The fine-grained steel ex…
Microstructure and mechanical propertiesMetallurgy and Material FormingMetal Alloys Wear and Properties
Raymond C. Stevens、Yuh Min Chook、Charles Y. Cho 等 5 位作者1991-01-01Protein Engineering Design and Selection
Crystal structures are known for aspartate carbamoyltransferase (ATCase) in the T and R states, with and without the allosteric activator adenosine triphosphate (ATP) or inhibitor cytidine triphosphate (CTP). Visual inspection of X-ray crystal structures does not provide all of the information necessary for the determ…
Enzyme Structure and FunctionAmino Acid Enzymes and MetabolismBiochemical and Molecular Research
C.T. Liu、C. L. Fu、E.P. George 等 4 位作者1991-01-01ISIJ International
In this paper we review experimental and theoretical findings related to the recently discovered mechanism of moisture-induced environmental embrittlement in FeAl-based alloys. We show that when low aluminum content FeAl alloys (35 and 36.5% Al) are tested in air, the aluminum in the alloys reacts with moisture in the…
Intermetallics and Advanced Alloy PropertiesAdvanced Materials Characterization TechniquesMetallurgical and Alloy Processes
Z. Trybuła、V. Hugo Schmidt、John E. Drumheller1991-01-01Physical review. B, Condensed matter
The mixed crystal ${\mathrm{Rb}}_{1\mathrm{\ensuremath{-}}\mathit{x}}$(${\mathrm{NH}}_{4}$${)}_{\mathit{x}}$${\mathrm{H}}_{2}$${\mathrm{AsO}}_{4}$ (RADA) has been investigated for several values of (x=0,0.12,0.15, and 0.20) by measuring the complex dielectric permittivity along the a tetragonal axis in the temperature…
earthquake and tectonic studiesSolid-state spectroscopy and crystallographyEarthquake Detection and Analysis
R. C. Newman、B.J. Webster、Robert G. Kelly1991-01-01ISIJ International
Sulfate-reducing bacteria can cause or influence corrosion in both carbon (or low-alloy) steels and stainless steels. The electrochemical reactions and rate-controlling processes are quite different in these two cases, the common feature being the catalysis of anodic dissolution by adsorption of hydrogen sulfide. In t…
Corrosion Behavior and InhibitionHydrogen embrittlement and corrosion behaviors in metalsConcrete Corrosion and Durability
Karl M. Kadish、Michelle Franzen、Baocheng Han 等 5 位作者1991-01-01Journal of the American Chemical Society
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTFactors determining the site of electroreduction in nickel metalloporphyrins. Spectral characterization of nickel(I) porphyrins, nickel(II) porphyrin .pi.-anion radicals, and nickel(II) porphyrin .pi.-anion radicals with some nickel(I) characterK. M. Kadish, M. M. Franzen, B…
Porphyrin and Phthalocyanine ChemistryPhotochemistry and Electron Transfer StudiesCO2 Reduction Techniques and Catalysts
Alan R. Mackie、J. Mingins、A.N. North1991-01-01Journal of the Chemical Society Faraday Transactions
The combined use of small-angle X-ray scattering (SAXS) and photon correlation spectroscopy (PCS) to characterise adsorbed layers of β-casein at the solid/liquid interface is reported. The protein was adsorbed to polystyrene latex particles at room temperature, low ionic strength and neutral pH and adsorption densitie…
Proteins in Food SystemsSurfactants and Colloidal SystemsPolymer Surface Interaction Studies