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。
Systematic investigations have allowed us to formulate a structural model representing the relationship between vitrification and mesogenity in low-molecular-weight liquid-crystalline compounds. The tendency to transform the highly viscous mesophases into glass phases is caused mainly by the bulkiness of the molecules…
A series of palladium clusters containing from four to several hundred Pd atoms in the metal skeleton has been prepared and characterized with respect to structure and chemical properties, including catalytic activity. For smaller clusters good agreement was observed. between single-crystal X-ray and EXAFS structural…
Photoluminescence and intramolecular energy-transfer properties of Eu2(H2O)12[Mo8O27]·6H2O, 1 have been determined in connection with the crystal structure. The compound has been prepared by treating K2[MoO4] with Eu(NO3)3 in aqueous solution at pH 3.0 and isolated in a crystalline form with a belt structure. A single…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTCleavage of the nitrogen-nitrogen bond in a high oxidation state tungsten or molybdenum hydrazine complex and the catalytic reduction of hydrazineRichard R. Schrock, Timothy E. Glassman, and Michael G. ValeCite this: J. Am. Chem. Soc. 1991, 113, 2, 725–726Publication Date (P…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTpH-responsive liposomes which contain amphiphiles prepared by using lipophilic radical initiatorHiromi Kitano, Yasumasa Akatsuka, and Norio IseCite this: Macromolecules 1991, 24, 1, 42–46Publication Date (Print):January 1, 1991Publication History Published online1 May 2002Pu…
Abstract Raman spectra of the CC stretching region of strained gel‐spun ultradrawn ultrahighmolecular weight polyethylene fibers were recorded. On the low‐wavenumber side of both the asymmetric and symmetric band, an additional broad band appeared during straining of the fiber, indicating the presence of CC bonds ex…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTStructure and catalytic activity of alumina-supported platinum-cobalt bimetallic catalysts. 1. Characterization by x-ray photoelectron spectroscopyZoltan Zsoldos, Tamas Hoffer, and Laszlo GucziCite this: J. Phys. Chem. 1991, 95, 2, 798–801Publication Date (Print):January 1,…
When an aqueous AgClO4–sodium dodecylsulphate (SDS)–isopropyl alcohol (Pri OH) solution was photolysed with 253.7 nm light, a sharp and intense absorption band of colloidal silver (λ= 390–400 nm) appeared after a relatively long induction period. In contrast, the sharp colloidal absorption rapidly developed when an Ag…
Abstract New soluble polyimides with inherent viscosities of 0.2–0.6 dL/g were synthesized from 3,4‐bis (4‐aminophenyl)‐2,5‐diphenylfuran and various aromatic tetracarboxylic dianhydrides by the conventional two‐step method which involved ring‐opening polyaddition and subsequent cyclodehydration. Almost all of the pol…
This review critically evaluates the suitability of Auger spectral line shape analysis as a source of electronic structure information. Methods for extracting the true Auger line shape from the raw data and a theoretical framework for semiquantitative interpretation of that line shape are presented. A wide range of re…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTLight-scattering study of kinetics of spinodal decomposition in a polymer solutionJyotsana Lal and Rama BansilCite this: Macromolecules 1991, 24, 1, 290–297Publication Date (Print):January 1, 1991Publication History Published online1 May 2002Published inissue 1 January 1991h…
Iron porphyrins containing perhalogenated pyrroles are found to be much better catalysts for the hydroxylation of poorly reactive alkanes like pentane or heptane by PhIO (yields as high as 80%) than the corresponding iron porphyrins without halogens on the pyrrole rings; the chemoselectivity and regioselectivity of th…
Expansion of the orientational distribution function f(θ, t) of molecular dipoles in terms of Legendre polynomials with spherical modified Bessel functions in(μE/kT) as coefficients yields an analytic relation between the steady-state birefringence Δnz(ω) and the electro-optic coefficient χxxz(2)(-ω;ω,0) for a poled n…
We report polarized two-photon excitation spectra of the $^{3}$${\mathit{A}}_{2}$${\ensuremath{\rightarrow}}^{3}$${\mathit{T}}_{2}$, $^{1}$E, and $^{3}\mathrm{T}_{1}$ transitions of ${\mathrm{Ni}}^{2+}$-doped MgO measured by detecting the $^{3}$${\mathit{T}}_{2}$${\ensuremath{\rightarrow}}^{3}$${\mathit{A}}_{2}$ infra…
High-level waste (HL W) is a natural component of the nuclear fuel cycle. Because of its radioactivity, HL W needs to be handled with great care. Different alternatives for permanently storing HL W are evaluated. Studies have shown that the disposal of HL W is safest when the waste is first vitrified before storage. S…
At temperatures below 60 K A2ReCl6(A = K, Rb, Cs) crystals emit intense, well resolved luminescence in the 13 900–12 800 cm–1 region under blue–green excitation. The emission is strongly temperature dependent and also depends somewhat on the excitation wavelength and crystal quality. It is here assigned as the vibroni…
ダイヤモンドライクカーボン(DLC)は,著しい低摩擦特性と高硬度とをあわせもつ長寿命の固体潤滑皮膜として有望である。低い温度で密着性よく皮膜形成する手段として,有機化合物の蒸着とイオン照射を併用したイオンビームアシスト蒸着法を紹介する。典型的なDLCである水素を含む非晶質炭素(a-C:H)は,真空中や乾燥雰囲気下では～0.02という著しく低い摩擦係数,μを示す。しかし水分を含む雰囲気下ではμは,0.2程度まで増大する。この水分による摩擦特性の劣化は,Siとの合金化によって著しく改善できる。すなわちa-C1-xSix:H(0.05≦x≦0.35)は,高湿度雰囲気下でもμ～0.05であり,真空中や乾燥雰囲気下ではμ≦0.02である。こ…
Two kinds of resins for molded transformers have been developed and their electric and mechanical characteristics were evaluated at various temperatures. Each resin has good characteristics below the glass transition temperature. During the past 12 years, 20000 molded transformers using these resins have been produced…
Abstract In single crystals of scapolite from two different localities, three paramagnetic centres are detected by electron paramagnetic resonance (EPR): 1. One isotropic singlet with g iso = 2.005; 2. One triclinic singlet with g ‖ = 2.005 ± 0.001 and g ⟂= 2.009; 3. One triclinic sextet with g ‖= 2.005 ± 0.001, g ⟂ =…
Grain boundary deformation measured using the electron lithographic microgrid technique has been found to give rise to regions of compressive longitudinal strain as well as strain concentrations in a uniaxial tensile creep test. The complexity of the experimental strain distribution is better explained by the use of a…