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。
The chromium(II) compound [C[graphic ommitted])-µ-Na(thf)2}2]1 has been isolated and structurally characterised; in combination with trimethylaluminium, it is a precatalyst for the polymerisation of ethene to linear polyethylene.
Abstract The results of the sorption and diffusion of aldehydes and ketones into structurally different elastomers such as ethylene propylene diene terpolymer, styrene butadiene rubber, nitrile butadiene rubber, neoprene and natural rubber are described in the temperature interval of 25‐60°C. From these data, the Arrh…
A series of copolyimides based on 3,3′,4,4′-biphenyltetracarboxylic dianhydride (BPDA), pyromellitic dianhydride (PMDA)(1,2,4,5,-benzenetetracarboxylic dianhydride) and 2,2′-bis(trifluoromethyl) benzidene (PFMB) have been synthesized with varying BPDA–PFMB and PMDA–PFMB compositions. A systematic change in the linear…
The effects of tensile pseudoelastic cycling of Cu–Zn–Al single crystals containing a dense distribution of small (≈10 nm) γ-phase precipitates have been studied. The σ-ε curves show a reduction of hysteresis after the first transformation cycles caused by a shift of the direct transformation to progressively lower st…
A series of fully aromatic copolyimides have been synthesized from 3,3′,4,4′-biphenyltetracarboxylic dianhydride (BPDA), pyromellitic dianhydride (PMDA), and 2,2′-bis(trifluoromethyl)-4,4′-diaminobiphenyl (PFMB) in m-cresol, (BPDA–PFMB)x-(PMDA–PFMB)y. The molar composition ratios are 100 : 0, 85 : 15, 70 : 30 and 50 :…
Lateral substitution in the peripheral phenyl groups of the triphenylen-2,3,6,7,10,11-hexayl hexakis(4-alkoxybenzoate)s has been investigated via dimethyl substitution ortho to the terminal alkoxy chain or the ester linking group. Similarly, lateral methyl substitution in the terminal alkoxy chain was also investigate…
The cation [Ru(C8H12)]2+ was supported on [P3O9]3–, [V4O12]4– and [Nb2W4O19]4– polyoxoanions. All the complexes were stable in air and were characterized by elemental and thermogravimetric analysis, IR, 1H, 13C and 31P NMR spectroscopy. The crystal and molecular structure of [NBu4][Ru(C8H12)(MeCN)-(P3O9)]·Et2O has bee…
The reaction of a nickel(II) imidazolate complex [NiL1](H2L1= 5-{o-[5-chloro-2-hydroxyphenyl)phenylmethyleneamino]phenyliminomethyl}imidazole) with iron(III) Schiff-base complexes [FeL2Cl], [FeL3]+ and [FeL4]+[H2L = R(NCHC6H4OH-o)2; R =(CH2)2(L1), (CH2)3NH(CH2)3(L2) or (CH2)3NMe(CH2)3(L3)] yielded the imidazolate-brid…
ABSTRACT Acetic acid solutions (0.5, 1.0 and 3.0%) were packed in polyethylene aluminum foil laminated material and adhesion between the layers was measured during 28‐days storage at room temperature (∼23°C). Peel tests showed that in 3% acetic acid adhesion between layers was almost totally lacking after 4 days. Afte…
This paper describes the application of ab initio molecular orbital (MO) theories in conjunction with reaction rate theory to obtain thermochemistry and energetics of nucleation processes. The specific example used for the illustration of this approach is the nucleation of SiO. MO computations on the equilibrium struc…
Abstract Zinc solubility in clay and soil suspensions was controlled by chemisorption at pH 4.5 – 7.0. The solubility in clay mineral suspensions was in the order palygorskite < montmorillonite « kaolinite and reflected the high affinity of zinc to palygorskite and the high CEC of montmorillonite. The solubility in…
The oxidation of primary aromatic amines to the corresponding nitro derivatives has been observed in catalytic systems (turnovers/hour up to 18000) containing tert-butyl hydroperoxide and metallo-tetraaryl porphyrins (metal = FeIII or MnIII) in the presence of heterocyclic nitrogen bases acting as axial ligands.
In this paper we report the synthesis and the structural, thermal, electrical properties of 1-D polymeric chlorocadmates(II), having N-methylpropane-1,3-diammonium (mepnH2) andlV^Vdiethylpropane-1,3-diammonium (et2pnH2) as countercations.The (mepnH2)2[Cd3Cli0] crys- tallizes in space group P2i/c.The unit cell dimensio…
Particulates of atmospheric interest, including soot, oxidized soot, and oxides of transition metals, “fellow travelers” in the combustion of solid or liquid fossil fuels, have been examined for their influence on the heterogeneous oxidation of S(IV) to S(VI), both with and without the presence of simulated solar radi…
The material (R)-1-methylheptyl 4-(4′-n-dodecyloxybiphenyl-4-ylcarbonyloxy)-3-fluorobenzoate has been prepared and its liquid-crystalline properties investigated. This material was selected for synthesis because it was expected to exhibit a ferroelectric smectic C* phase with a large value for its spontaneous polariza…
The interaction of AlMe3 with the polydialkylsiloxanes (OSiRMe)x and (OSiPh2)3 for long periods at elevated temperatures leads to the rupture of the silicon–oxygen framework and yields dimeric dimethylaluminium siloxides [Me2Al(OSiMe2R)]2, R = Me (1), n-C6H13(2), n-C8H17(3), n-C14H29(4), n-C18H37(5), -CH2CH2CF3(6), Ph…
Abstract On the basis of sterical and electrostatical arguments, it is deduced that the stoichiometry of Na + ‐ and CO 3 2‐ ‐containing calciumhydroxyapatite can be accounted for by 6 substitution mechanisms magnified image where V x stands for a vacancy in the X‐sublattice. It is shown that every mechanism proposed i…
Expressions to describe the initial collection efficiency of electret filters for both charged and neutral particles were derived covering a wide range of Coulombic force and induced force parameters including the interceptional effect. The prediction equations were in good agreement with the experimental data. Furthe…
The binary lyotropic liquid crystalline system caesium pentadecafluoro-octanoate (CsPFO)/water (2H2O) exhibits an isotropic micellar phase, a lyotropic nematic phase and a positionally ordered, lamellar phase whose planes contain substantial water filled defects. It has been suggested that the structural unit in all t…
A simple and accurate method for determination of filler material density is described. Rice husk ash (RHA) which consists predominantly of silica serves as a filler in polypropylene. The filler density was determined from first principles using a pyknometer. The filler was compounded in polypropylene and the densitie…