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 local structural arrangement of ions around a substitutional Cr 3+ ion in sapphire (ruby) has been studied experimentally using extended X‐ray absorption fine structure (EXAFS) in the vicinity of the Cr absorption edge. The findings are compared with an ionic model (Mott‐Littleton) computation using two sets of pa…
The solution of the cubic crystal form (a = 167.8 A) of concanavalin A complexed with the monosaccharide methyl alpha-D-glucopyranoside is described. The space group has been determined as I2(1)3 rather than I23. The use of cadmium to replace cobalt at the transition metal-ion binding site and to replace calcium at it…
The literature on the setting mechanisms of dental amalgams made from powders of silver-rich alloys of tin and/or copper has been critically reviewed. In Part 1 of the review, the microstructure and phase content of recently set amalgams are described. The composition, morphology, and location of product phases are em…
Flashover of wet polluted insulation is caused by the propagation of arcs along the electrolytic surface. Several factors affect this flashover process under actual operating conditions. These include the variation in pollution resistance due to arc root movement and thermal effects. The difference between the dischar…
Eight different nickel porphycenes bearing substituents on the pyrrole β and/or ethylenic carbon positions of the macrocycle were investigated as to their redox properties in benzonitrile containing 0.1 M tetrabutylammonium perchlorate. Half-wave potentials were utilized to evaluate the effect of substituents and exte…
Reaction of manganese(II) perchlorate hexahydrate with a methanol solution of 1-thia-4,7-diazacyclononane ([9]aneN(2)S) resulted in the isolation of the manganese(II) complex [Mn([9]aneN(2)S)(2)](ClO(4))(2). The X-ray structure of this complex is reported: crystal system orthorhombic, space group Pbam, No. 55, a = 7.9…
Abstraet-The laser contact angle goniometry technique was applied to measure the wettability of water droplets on polymer surfaces in different normal alkanes. Using the modified two-liquid contact angle technique and the model recently proposed by us, we can determine the dispersive and non-dispersive (acid-base) con…
The adsorption and reaction of maleic anhydride and deuterated maleic anhydride on Mo(110), monolayer Pd/Mo(110), and multilayer Pd(111)/Mo(110) surfaces have been studied using temperature-programmed desorption (TPD) and high-resolution electron energy loss spectroscopy (HREELS). Maleic anhydride adsorbs irreversibly…
Mononuclear nitrido complexes of Cr and Mo, NCr(OBut)3 and NMo(OSiMe3)3(py), are synthesized; the chromium complex has an idealized C3ν symmetry while the molybdenum complex has a distorted square-pyramidal geometry with the nitrido ligand at apical position; the N–Cr distance is 1.538(5)Å while the average N–Mo dista…
Dithizone and thiosemicarbazide were investigated as inhibitors of the corrosion of type 304 stainless steel in 1·0M sulphuric acid solution by studying weight loss, polarisation curves, and polarisation resistance and using scanning electron microscopy and Auger electron spectroscopy. Various corrosion parameters suc…
Biodegradations of random copolymers of ( R )-3-methyl-4-oxa-6-hexanolide [( R )-MOHEL] with various lactones such as ε-caprolactone (24/76 ratio), δ-valerolactone (22/78), and β-propiolactone (31/69) were examined with normal or acclimated activated sludge. As a consequence, the biodegradability was found to increase…
Core losses of an 18.5 kW asynchronous motor were measured and computed, by means of a suitable electromagnetic fields package, improved for core loss calculation. The results show that a 1 to 3% improvement in efficiency is possible by replacing the conventional soft laminations by new materials. The differences betw…
The synthesis of a new class of high-barrier polymers, poly(hydroxy amide ethers), is described. The polymers are formed by the reactions of bisphenol-A diglycidyl ether, OCH 2 CHCH 2 OC 6 H 4 C(CH 3 ) 2 C 6 H 4 OCH 2 CHCH 2 O, and amide-containing bisphenols of the general formula HOC 6 H 4 NHC(O)RC(O)NHC 6 H 4 OH [R…
Poly(siloxyethylene glycol) (PSEG), which consists of alternating oligo(dimethylsiloxane) and oligo(ethylene glycol) (OEG) units in the main chain, was synthesized through polycondensation reactions between oligosiloxane having two diethylamino groups and OEG. The molecular weight of the polymer was in the range 3500−…
The electronic structure of small clusters forming the inorganic cores in cadmium thiolate complexes is analyzed on the basis of semiempirical quantum chemical calculations. Orbital energies, atom charges, and peculiarities of chemical bond formation are considered for sphalerite lattice fragments Cd x S y ( x ≤ 20, y…
Femtosecond transient absorption and picosecond fluorescence spectra and kinetics have been measured for an ethylene-bridged porphyrin dimer molecule, trans -1,2-bis( meso -octaethylporphyrinyl)ethene (tbis OEP). In part 1 of this work it was shown with the help of absorption and fluorescence spectroscopy that in solu…
Two new copper(I) arenethiolates with ortho -chelating nitrogen donor atoms [Cu(SC 6 H 4 NMe 2 -2)] 3 ( 5 ) and [Cu(S-1-C 10 H 6 NMe 2 -8)] 9 ( 6 ) have been synthesized by reacting Me 3 SiSAr (Ar = C 6 H 4 NMe 2 -2 or 1-C 10 H 6 NMe 2 -8) with copper(I) chloride in a 1:1 molar ratio. Copper(I) arenethiolate 5 is a wh…
Addition of TCNQ to a solution of tetrakis(dimethylamino)ethylene in MeCN produces the salt [TDAE][TCNQ]2; the dipositive cation, [{(CH3)2N}2C–C{N(CH3)2}2]2+, is nonplanar, with a dihedral angle of 63.9°, while the TCNQ anions crystallize as [TCNQ]22– dimers with an interplanar separation of 3.16 Å. The complex [TDAE]…
Stoichiometry dependent hydrolysis of (arylamino)-silyltrichlorides using anhydrous N2H4 as the HCl acceptor and dehydrating agent leads to the formation of the primary and secondary condensation products of silanetriols, tetrahydroxydisiloxanes [Ar(SiMe3)NSi(OH)2]2O and cyclotrihydroxytrisiloxanes [Ar(SiMe3)NSi(OH)O]…
Oxidation of CoII by HSO5– to CoIII in weakly acidic solution, in the presence of molybdate, resulted in the formation of (primarily) the soluble dicobalt species [H4Co2Mo10O38]6–. The kinetics of formation of this species was examined at 15–35 °C over the range pH 4.0–5.5 and found to exhibit three separate kinetical…