Materials Literature
按标题、摘要、年份、主题和来源检索公开元数据。结果保留作者、摘要、分类与原始来源链接。
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTKeto-enol tautomerism and vibrational spectra of phenylpyruvic acidsKazuhiko Hanai, Akio Kuwae, Satoshi Kawai, and Yoko OnoCite this: J. Phys. Chem. 1989, 93, 16, 6013–6016Publication Date (Print):August 1, 1989Publication History Published online1 May 2002Published inissue…
The proton NMR spectra of a variety of low-spin and high-spin ferric complexes of the naturally occurring chlorin derivative pyropheophorbide a methyl ester have been recorded and assigned. The complete assignments for the low-spin, dicyano complex were effected by a combination of partial isotope labeling, paramagnet…
Ligands such as complexing organic acids play a significant role in the dynamics of release of plant nutrients in soils. The objective of this work was to study the dynamics of slowly exchangeable K and Mg release from 12 Quebec soils by ten successive extractions with 5 × 10 −4 M citric acid, over a period of 1800 h,…
The method of strained coordinates is applied to the inward solidification problem. Constant thermal properties are assumed throughout the analysis for the liquid, which is initially at the fusion temperature. A unified approach is adopted that allows the simultaneous treatment of the problem in plane, cylindrical, an…
For momentum transfers of order 6 A${\r{}}^{\mathrm{\ensuremath{-}}1}$ nondipole transitions can make the same contribution to inner-shell energy-loss spectra as dipole transitions. Nondipole transitions are particularly significant when there is a high density of dipole-forbidden states in the near-threshold region.…
The densification and shear behavior of glass powder compacts were determined by measuring their axial strain and radial strain during uniaxial compression. The experiments were conducted nonisothermally at constant rates of heating. The densification and the shear strain were plotted as a function of temperature. Bot…
A theory is presented for estimating the stopping of bound electrons, whose internal system described in momentum space is considered as a dense interacting electron gas with a Gaussian occupation probability. With the use of an alternative type of random-phase-approximation dielectric function proposed herein, the sh…
Abstract 1 H and 2 H NMR spectra were recorded for the paramagnetic metallocenes Cp 2 M (M = V, Cr, Mn, Co, Ni). For Cp 2 V, Cp 2 Cr, Cp 2 Mn and Cp 2 Ni, a signal narrowing factor of 36–37 is observed on going from Cp 2 M‐ h 10 to Cp 2 M‐ d 10 , which is close to simple theoretical predictions. Additional quadrupolar…
Europium oxide has been investigated as a sintering aid and dopant for AIN. Pressureless sintering was carried out with 0 to 9 wt% Eu 2 O 3 additives, and dense sintered specimens were obtained using 1 to 4 wt% Eu 2 O 3 . With increasing Eu 2 O 3 content, two additional phases were observed in the X‐ray diffraction pa…
A vanadium oxide glass has been prepared by a rapid quenching technique, and the electrochemical lithium insertion into the glass has been investigated. The open‐circuit voltage (OCV) of the lithium cell with the glass gradually is decreased with increasing the stoichiometric parameter , while OCV of crystalline has t…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTESR study of the dynamic molecular structure of a reentrant nematic liquid crystalAkbar Nayeem and Jack H. FreedCite this: J. Phys. Chem. 1989, 93, 17, 6539–6550Publication Date (Print):August 1, 1989Publication History Published online1 May 2002Published inissue 1 August 19…
Abstract This paper describes the development of process control schemes for the free radical initiated (reactive) degradation of polypropylene in an extruder (reactive extrusion). The objective of the work was to control the amount of degradation in order to produce polypropylene with a specified molecular weight. Th…
Direct current and alternating current electrical conductivity measurements are used to determine the activation energies for the formation of oxygen vacancies by breakup of bound defect complexes (0.32 eV) and their migration (0.84 eV) at low temperatures (<600°C) in Y 2 O 3 ‐fully‐stabilized ZrO 2 single crystals…
The adhesion of micro‐organisms to metal surfaces has been shown to be important in the corrosion process, but the cell surface structures participating in this adhesion have not previously been identified. Evidence is presented that a bacterial substance taking part in the initial adhesion of Pseudomonas fluorescens…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTLiquid crystalline polyethers and copolyethers based on conformational isomerism. 3. The influence of thermal history on the phase transitions of the thermotropic polyethers and copolyethers based on 1-(4-hydroxyphenyl)-2-(2-methyl-4-hydroxyphenyl)ethane and flexible spacers…
This work deals with the changes in mechanical properties of yttrium oxide ceramics induced by nonstoichiometry. The maximum fracture toughness, K lc , is observed at the stoichiometric composition. For an oxygendeficient ceramic, a decrease of K lc is observed from 3.5 to 2.3 MPa.m 1/2 . On the other hand, the Vicker…
In an effort to clarify the effects of molybdenum, which greatly retards the kinetics of temper embrittlement of alloy steels, the incidence of intergranular fracture and the segregation of phosphorus and other elements to grain boundaries were studied in a series of Fe-Mo-P alloys by means of fracture experiments in…
Abstract The production of a polymer containing basic functional groups via the reactive processing of polyethylene was investigated. Grafting of dimethylamino ethyl methacrylate, DMAEMA, to linear low‐density polyethylene in the melt was carried out, and the effects of initiator type, feed composition, and reaction t…
Effects of n -type dopants Si and Se on band-gap energy ( E g ) and on sublattice ordering for Ga 0.5 In 0.5 P grown by metalorganic vapor phase epitaxy, under conditions in which E g shows anomalously low E g values if the doping is not carried out, were studied by means of photoluminescence and transmission electron…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTPhotoinduced electron transfer on a single .alpha.-helical polypeptide chainMasahiko Sisido, Ryo Tanaka, Yoshihito Inai, and Yukio ImanishiCite this: J. Am. Chem. Soc. 1989, 111, 17, 6790–6796Publication Date (Print):August 1, 1989Publication History Published online1 May 20…