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。
Frustulia bahlsii sp. nov. is formally described from soft-water sites from Maine to North Carolina along the eastern United States. The new species is separated from other members of the genus by the following suite of characters: large size, spatulate terminal raphe ends (i.e. not provided with a “porte-crayon”), an…
Abstract The new compound SrCuTe 2 O 6 has been prepared by quenching single crystals grown from a flux of SrCO 3 , TeO 2 and CuCO 3· Cu(OH) 2 . X-ray investigations show cubic symmetry, space group O 7 -P4 1 32, lattice constant a = 12.473(1), Z = 12. The crystal structure is characterized by square planar CuO 4 poly…
In the synthesis of dexamethasone acetate from tigogenin, the introduction of the 17α-hydroxy-16α-methyl and the 1,4-diene moieties was improved. For the introduction of the 17α-hydroxy-16α-methyl moiety, the key step, epoxidation, was accomplished in high yield with peracetic acid in a buffer solution of sodium aceta…
The shapes, sizes, and distribution of second phase precipitates are the principal factors determining the mechanical, electrical, and magnetic properties of a wide variety of high technology alloys and ceramics. In the initial processing, and also in high temperature applications, such as jet engine superalloys, the…
We have investigated the effect of a metal coating—copper—on the tetragonal structure of fine barium titanate (BaTiO 3 ) particles. The BaTiO 3 particles were synthesized by a sol‐gel method and heat treated at temperatures >900°C for various amounts of time before coating. The copper coating was achieved by an ele…
This paper is concerned with the application of a modification process to cotton friction spun singles yarns. The experimental results show that the yarn modification process can effectively reduce or eliminate residual torque in dref-III singles yarns as well as fabric spirality in plain knitted structures. The prope…
The kinetic behavior of NO reduction by CO over a Pt/Al 2 O 3 catalyst has been investigated in the temperature range of 465−520 K. The NO + CO reaction exhibits isothermal steady-state multiplicity. A high-conversion steady state was obtained starting with a net oxidizing feed composition ([NO] 0 > [CO] 0 ), and a lo…
PURPOSE: Previous observations in rats caused us to speculate whether the injection of iotrolan, a nonionic dimeric contrast medium (CM), would increase urine viscosity enough to obstruct urine outflow in the collecting duct. MATERIAL AND METHODS: The urine viscosity in dogs was measured directly with a viscosimeter a…
4-Hexadecyloxyphenyl-4-carboxybenzoate (A) and 4-carboxyphenyl-4-hexadecyloxy benz- oate (B) were prepared and thermally characterized by polarized light microscopy and differential scanning calorimetry. Both compounds possess high transition temperatures indicating the formation of linear dimer molecules in the solid…
Transverse magnetoresistance for paramagnetic ${\mathrm{Mn}}_{x}{\mathrm{TiS}}_{2}$ $(0.02<~x<~0.25)$ crystals has been measured at three fixed temperatures 77, 4.2, and 1.8 K at fields up to 31 T using a compact home-made pulsed magnet. We have found a large negative magnetoresistance $\ensuremath{\Delta}\ensur…
Integral skin foams consist of a cellular core and a near solid skin of the same material surrounding the core. A study of the effect of mica on the flexural properties of free rise and integral skin polyurethane foams is presented. Addition of a small amount of mica (5% v/v) is found to significantly increase the fle…
To evaluate the serviceability of a new textile product made of an unconventional fiber blend, it is important to determine if the fabric meets the specific standards required for the intended end-use. The value-added textile products of interest are fabrics made of 50/50 kenaf/cotton in the filling direction and 100%…
Shape memory alloys (SMA) show a high ratio of work capacity per material volume. This makes the application of SMA especially useful in micron-sized systems. The development of robotic grippers is one important prerequisite for the successful automation of the assembly of micro systems. Therefore the SMA may also pla…
The compounds Mn 8 [BeSiO 4 ] 6 X 2 (X = S, Se, Te) Mn 8 [BeGeO 4 ] 6 X 2 (X = S, Se) have been synthesized by solid state reactions of the constituent oxides and MnX at 1000−1100 °C in sealed quartz ampules. The materials crystallize with the cubic sodalite unit cell with an ordered Be/Z 4+ (Z 4+ = Ge/Si) framework i…
The structure of the superionic glass ${(\mathrm{L}\mathrm{i}}_{2}{\mathrm{S})}_{0.5}{(\mathrm{S}\mathrm{i}\mathrm{S}}_{2}{)}_{0.5}$ has been studied using Li-isotopic-substitution neutron diffraction. A marked difference has been observed in the intensity of the first sharp diffraction peak (FSDP) in the structure fa…
A student experiment is described concerning properties of ferromagnets near the Curie point. Gadolinium provides a good opportunity to determine the magnetic susceptibility above the transition point and to evaluate the critical exponent of the susceptibility. The temperature dependence of the electrical resistance o…
We present Cs2NaYF6:Ce3+ or Pr3+ as new x-ray storage phosphors. The radiation damage centers upon x irradiation were investigated using magneto-optical and magnetic resonance spectroscopy. F centers are the photostimulable electron trap centers. For the activator Pr3+ it could be shown that upon room temperature x ir…
Abstract Proton NMR second moments and spin-lattice relaxation times of polycrystalline C(NH 2 ) 3 PbI 3 and [C(NH 2 ) 3 ] 2 PbI 4 were studied in a wide temperature range. The order-disorder character of the existing solid-solid phase transitions was confirmed and for tetraiodoplumbate a new phase transition at 170 K…
Physicochemical and structural properties of microbial cell surfaces play an important role in their adhesion to surfaces and are determined by the chemical composition of the outermost cell surface. Many traditional methods used to determine microbial cell wall composition require fractionation of the organisms and c…
Secondary electron emission properties from crystalline and polycrystalline diamond films containing different boron concentrations were measured. The secondary electron yields δ were high. Yields were independent of incident beam angle and crystallographic orientation. The secondary electron yields were greatest for…