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 optical absorption spectrum of Tm 3+ in TmVO 4 has been studied to obtain information on the cooperative Jahn-Teller phase transition which occurs in this material at 2.14+or-0.04 K. The temperature dependence of the absorption lines below 2.14 K was in good agreement with the predictions of molecular field theory…
The adsorption of di- and tri-methylamine has been studied at 280 and 276°K, respectively, on a range of silica gels and on silica–alumina. Adsorption–desorption isotherms and isothermal calorimetric heats of adsorption were measured. Heats of adsorption for di-methylamine on silica gel varied from 29.0 kcal/mol at θ…
A phase diagram of the semiconducting uniaxial ferroelectric antiferromagnetic Fe1-xS covering the available experimental evidence is given.
Two aminoacylases [EC 3. 5. 1] from Mycobacterium smegmatis were purified as single protein components, based on analysis by ultracentrifugation and electrophoresis. The enzyme, “short acyl aminoacylase” which exhibited hydrolytic activity toward N-short chain fatty acyl amino acids, had a sedimentation coefficient s2…
In an investigation of X-ray counting circuits the fundamental quantity governing component interaction and system counting efficiency was the pulse duration associated with a single counting event. Theoretical expressions governing the behaviour of counting systems consisting of two components were derived assuming e…
The radiation-induced bulk polymerization of liquid hexamethylcyclotrisiloxane has been achieved. Appreciable yields of polymer from octamethylcyclotetrasiloxane liquid have also been obtained. These results were achieved on “ultra-dry” monomers and are interpreted in terms of an ionic polymerization mechanism.
The thermodynamics of a water‐vapor‐E‐glass system were studied by adsorption‐isotherm analysis. The seven isotherms completed were Brunauer type IV with permanent hysteresis. The first adsorbed water layer could not be removed by pumping, indicating permanent hydrolysis. Application of heat removed the remaining wate…
Abstract The methods of Hermans and Weidinger and of Wakelin et al. (the correlation and integral methods) were used to determine the degree of crystallinity in poly(ethylene terephthalate) (PET) fibers. A standarization of cutting of the amorphous background scattering in PET fibers, indispensable for the method of H…
The crystal structure of Ca(H2AsO4)2 (triclinic, PT, with two formula units per cell) has been refined by single-crystal neutron-diffraction analysis to give an R value of 0.025 over 930 independent neutron reflexions. For the non-hydrogen atoms, bond lengths, angles and thermal parameters agree very closely with the…
Abstract Interlayer K was extracted with sodium tetraphenylboron solution from a powdered sericite heated to the temperature of dehydroxylation and quenched to room temperature. By this procedure, sericite of the 2 M 1 type was changed to an interstratified mineral. The X-ray diffraction properties of this interstrati…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTChemical studies of closo-1,5-dicarbapentaborane(5)Anton B. Burg and Thomas J. ReillyCite this: Inorg. Chem. 1972, 11, 8, 1962–1964Publication Date (Print):August 1, 1972Publication History Published online1 May 2002Published inissue 1 August 1972https://pubs.acs.org/doi/10.…
Gold films are used as an alloying flux to form 5 μ thick indium film seals at temperatures below 300°C. Pyrex was sealed to quartz, ULE, CER-VIT, Irtran 2, Ge, GaAs, Invar, Kovar, Al, and Cu. The seals can also be used as current feedthroughs and graded seals.
The structure of ferroelectric tetragonal KTN (KTaxNb1 - xO3 with x = 0.56), which is isomorphous with BaTiO3, has been determined by neutron diffraction. The atomic displacements from the cubic perovskite positions are δ(K) = 0.012 ± 0.003, δ(Ta,Nb) = 0.0003, δ(O(1)) = -0.010 ± 0.001 and δ(O(2)) = δ(O(3)) = -0.011 ±…
Transmission electron microscopy and selected area electron diffraction have been used to study the structural changes produced in thin (0001) crystals of NbSe2 and MoS2 by intercalation with sodium in ammonia solution. Three distinct superlattice structures have been identified, one, with orthorhombic symmetry, assoc…
Abstract Rare earth carbonates which give the same X-ray powder diffraction pattern as tengerite were prepared by heating aqueous solutions containing rare earth chlorides and ammonium trichloroacetate. Y, Er, Ho, and Gd gavee xactly the same X-ray powder pattern as tengerite, while Nd and Sm were similar to tengerite…
The room temperature Gd3+ EPR spectrum in SrF2 containing Ce3+ as a second dopant exhibits three types of symmetry sites: cubic, trigonal, and tetragonal. Relative intensities of the spectra from these sites have been determined as a function of the Ce3+ codopant level in crystals having nominally 0.1 molar % of Gd3+.…
Article Wasserstoff in intermetallischen Phasen am Beispiel des Systems Titan-Nickel-Wasserstoff was published on August 1, 1972 in the journal International Journal of Materials Research (volume 63, issue 8).
Abstract The magnetic susceptibilities of CuX2L (X: halide ion, L: 1,2,4-triazole, pyridazine, phthalazine, 4-amino-1,2,4-triazole) conform to the linear Ising model or Heisenberg model, indicating the presence of linear magnetic chains in the crystals. Fermi contact shift observed in the broad-line PMR spectrum indic…
The structure of ammonium hydrogen sulphate (AHS) has been determined in an (010) projection from X-ray diffraction data collected photographically at - 81°C. At this temperature AHS is in its ferroelectric phase. The asymmetric unit of the pseudo-orthorhombic unit cell (space group Ba) contains four formula units whi…
Abstract An aspartate racemase has been purified approximately 60-fold from the supernatant fraction of Streptococcus faecalis (ATCC 9790), a gram-positive organism whose peptidoglycan is cross-linked by d-isoasparagine residues. This partially purified preparation racemizes l-alanine about half as rapidly as it racem…