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。
4-n-Alkyl-4′-cyanobiphenyls (1) have achieved widespread application as stable thermotropic liquid crystals with mesophases at room temperature. The importance of the cyano functional group in the liquid-crystalline behaviour of these compounds is not clearly defined. By modifying this functional group with minimal ch…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTSynthesis, characterization, and rubber elasticity of end-linked poly(tetrahydrofuran) elastomerLei Jong and R. S. SteinCite this: Macromolecules 1991, 24, 9, 2323–2329Publication Date (Print):April 29, 1991Publication History Published online1 May 2002Published inissue 29 A…
Abstract The plate method was used to measure the surface tension of different epoxy prepolymers and different hardeners. The values are correlated to the chemical structure. The effect of molecular weight is very weak for diglycidyl ether of bisphenol A (DGEBA) prepolymers. For α,ω‐diamino‐terminated poly(propylene o…
Regions of incomplete charge collection, or dead layers, are compared for Si(Li) detectors fabricated with Au and Pd entrance-window electrodes. The dead layers were measured by characterizing the detector spectral response to X-ray energies above and below the Si K alpha absorption edge. It was found that Si(Li) dete…
A new data-acquisition and display system has been developed for magnetic domain observation using spin-polarized scanning electron microscopy. The system is composed of 32 frame memories (512×512×16 bit), an image processor with two high-speed digital signal processors, and a 1280×1024 pixel color monitor. It has the…
Chitosan has been reductively N-alkylated with a 6-O-substituted galactose derivative bearing an iminodiacetate residue, to give a chitosan derivative having a hydrophilic branch and a metal chelating group. The Cu(II) binding capacity of the derivative was comparable to native chitosan, but showed better ion-exchange…
Article Cross Sections for the 100 MeV Proton-Induced Nuclear Reactions and Yields of some Radionuclides Used in Nuclear Medicine was published on April 1, 1991 in the journal Radiochimica Acta (volume 54, issue 2).
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTCharacterization of hydrolytically degradable amino acid containing poly(anhydride-co-imides)Andrea Staubli, Edith Mathiowitz, Melissa Lucarelli, and Robert LangerCite this: Macromolecules 1991, 24, 9, 2283–2290Publication Date (Print):April 29, 1991Publication History Publi…
Abstract The dependences of phase structure and notch impact strength on conditions of mixing have been compared for the binary blend PP/EPDM and for two ternary blends PP/EPDM/PE possessing different viscosities of polyethylene. At low rates and short times of mixing a phase structure with pronounced inhomogeneities…
Thermal expansion was measured in two crystals of blue bronze (${\mathrm{K}}_{0.3}$${\mathrm{MoO}}_{3}$). At the Peierls temperature, the expansion coefficients exhibited a small steplike decrease along the chain direction, a nearly negligible change perpendicular to the cleavage planes, and a large steplike increase…
The passive film on a zinc electrode is often assumed to be composed of . Since removal of the electrode from the solution could alter the film composition, an in situ measurement technique is required for a qualitative analysis. We have developed a model to simulate the kinetics of anodic dissolution and passivation…
Abstract A new vertical microfurnace‐type pyrolyzer for thermal desorption and/or pyrolysis‐gas chromatography has been developed. The pyrolyzer consists of two independent temperature‐controlled ovens. Initially, in the desorption process, a sample cup containing the polymeric sample of interest is inserted into an o…
The acyl cyanides 1a — d are prepared from the corresponding acyl chlorides. The Paternó‐Büchi reaction of 1a — f with furan ( 2 ) yields the bicyclic oxetanes 3a — f with an endo / exo ratio varying from 3.5: 1 ( 1a ) to 16: 1 (1 d ). However, in the reaction of the chiral acyl cyanides 1b and 1c , a low chiral induc…
Abstract Elastomeric polymer consisting of poly(oxytetramethylene) segments and viologen units (PTV) was synthesized by the reaction of dicationic living poly(tetrahydrofuran) with 4,4′‐bipyridine at −70°C. The chloride or bromide ion was introduced as the counter anion into the viologen groups of PTV by the treatment…
An investigation of the synthesis by the flux method and the characterization of for cathode ray tube application is presented. In order to obtain an excellent europium distribution inside the matrix, an yttrium‐europium coprecipitated oxide has been used as the raw material. The optimization of firing conditions has…
Although calcium ions are crucial in a variety of bacterial processes, including spore development, reports of calmodulin in procaryotes have been few. We have purified to homogeneity a calmodulinlike protein (CaLP) from sporulating cells of Bacillus subtilis grown in a chemically defined sporulation medium; purificat…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTSmall-angle x-ray scattering from dilute solutions of substituted phthalocyaninato-polysiloxanesThomas Sauer and Gerhard WegnerCite this: Macromolecules 1991, 24, 9, 2240–2252Publication Date (Print):April 29, 1991Publication History Published online1 May 2002Published iniss…
If permanent setting of the wool fibre, which occurs during dyeing, can be restricted, the impairment of physical properties is reduced. This can be achieved by adding an oxidising agent, such as potassium bromate or hydrogen peroxide, to the dyebath. Oxidising agents also restrict the extent to which hygral expansion…
Mean depths and profiles of charge distributions in 34 to 40 mu m thick polypropylene films during and after injection of 10 to 40 keV electrons are investigated with the split Faraday cup and the laser-induced pressure pulse methods. For an open front (irradiated) electrode, the mean charge depth increases with time…
Crystalline hydroxyapaiite ultrafine particles were synthesized by hydrothermal treatment of the same powders prepared by mining aqueous ratio of Ca to P (1·67) at room temperature. The relations of the particle size and shape to such operating conditions as hydrothermal temperature, Ca(NO3) 2 concentration, stirring…