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 first non-calamitic/disc-shaped metal organyl series 3 and 6 containing two or even four palladium atoms and eight or twelve flexible side chains presented here have been synthesized via the novel roof-shaped/bent dimers 2 or (the thermomesomorphic) 5, respectively. In addition, from the chemical point of view the…
The ~nduction of sexuality was documented during a fall bloon~ of the marine diatom Ditylum brightwellii.Large numbers of cells bearing male and female gametes and some resting spores occurred simultaneously.When laboratory cultures of D. brightwellii became sexual after nitrogen starvation, sinking rates of cells in…
The controlled growth of semiconductor clusters from a precursor phenyl-capped CdS molecule, [Cd10S4(SPh)16]4–, by the addition of stoichiometric amounts of sulfide ion has led to a material having a sharp (full width at half-maximum at room temperature ≈ 800 cm–1) excitonic feature at 351 nm (3.53 eV) in its absorpti…
A TGM beamline for the spectral range 12–310 eV is being built at Laboratório Nacional de Luz Síncrotron (LNLS). This beam line consists of safety devices, a condensing mirror, a toroidal grating monochromator, and a refocusing mirror. This beam line has been assembled up to the exit slits. A spherical grating monochr…
Oxidative deprotonation of [M(P)(NH2But)2][M = Ru, Os; P= porphyrin dianion] gives [Ru(P)(O)(NBut)], [Os(P)(O)(NBut)]and [OS(P)(NBut)2], which are characterised by IR and 1H NMR spectroscopy.
[4′-(Dimethylamino)biphenyl-4-yl]dimesitylborane (BNB) and 4-[4′-(Dimethylamino)pnenylazo]phenyldimesityl-borane (BNA) have been investigated by X-ray diffraction; crystallographic data were used to calculate dipole moments in the ground state and the hyperpolarizability coefficient βo was measured by the EFISH techni…
An important step in understanding how a protein folds is to determine those regions of the sequence that are critical to both its stability and its folding pathway. We chose phosphoribosyl anthranilate isomerase from Escherichia coli, which is a monomeric representative of the (beta alpha)8 barrel family of proteins,…
The aging of epoxy electrical insulation by unipolar, repetitive voltage surges has been investigated to determine whether such surges can precipitate premature failure of high-voltage motor windings and gas insulated switchgear spacers. A full factorial statistical test was devised and performed on 180 pure epoxy ins…
Chitosan-like materials were extracted from five different fungal cells with NaOH and acetic acid, with the yields varying from 1.2 to 10.4% of the dry fungal cell weight. The degree of N-acetylation of the extracts measured by the colloidal titration method varied considerably depending on the individual species. By…
Crystal geometry and symmetry Diffraction geometry and its practical realization Preparation and examination of specimens Determination of lattice parameters Interpretation of diffracted intensities Measurement of intensities Refinement of structural parameters Basic structural features Precautions against radiation i…
In response to severe quality requirements resulting from remarkable progress in rolling techniques, composite type high performance roll was developed. With the adoption of this method, tough core metal, fine structure and high alloy at shell metal can be obtained with ease. Rolls with shell metal of high speed tool…
Abstract Sandy Coastal Plain soils have relatively low reserves of K and may not be able to supply adequate K for intensive corn ( Zea mays L.) production. Field experiments were conducted on Dothan loamy sand (fine‐loamy, siliceous, thermic Plinthic Paleudult) for 3 y to determine K fertilizer rate and placement effe…
Net-collected Ethmodiscus spp. were examined and found to be capable of positive buoyancy with ascent rates averaging 1.4 m h−1 on individually measured cells, and 0.3 m h−1 using a homogeneous settling technique. These data, together with published reports of positive buoyancy in Rhizosolenia, indicate that upward mo…
The purpose of this paper is to review the multiscattering models for spherical particles, quasistatic mixture laws, effective medium theories, percolation equations, and finally the general effective medium equation (GEM), which are all used for modeling the dielectric properties of complex mixture materials. These a…
A large glass forming region, which includes both homogeneous and phase separated glasses, has been found for the yttrium aluminosilicate system. Both the density (2.9 to 3.7 g/cm 3 ) and refractive index (1.54 to 1.72) of these glasses increase dramatically with increasing yttria content, but only slightly with incre…
Reaction of silica, montmorillonite and polystyrene bearing amino functions with several polyhalogenated metalloporphyrins gave an easy one-step access to new supported catalysts, owing to a selective nucleophilic substitution of the para-halogen atoms of the porphyrin meso-aryl groups by the polymer amine function; t…
The barium titanates BaTiO3, Ba2TiO4, BaTi2O5 and BaTi4O9 can be synthesized by a sol–gel method at low temperatures. The reaction between barium acetate solutions and titanium(IV) isopropoxide leads to the formation of barium titanate gels. The gels can be converted to the barium titanates by drying and calcination.…
A new, better method of producing cotton covered/polyester staple-core yarn on a modified ring spinning frame is described. The method uses the concept of twisting a “sandwich” formed by two drafted strands of cotton (rovings) on the outside and a drafted strand of polyester on the inside, thus using a total of three…
The shapes of 112 Co(II)O 6 polyhedra in 72 crystal structures of inorganic compounds were analyzed in this study. Most of these polyhedra are significantly distorted from the ideal octahedral symmetry m 3 m , observed point symmetries of the Co(II) sites are: 1(34%); [unk](29%); 2(14%); m (7%); 2/ m , 3(4%); [unk] m…
Rhodesite from Zeilberg, Unterfranken, Germany ( Z ), from Trinity County, California, USA ( TC ), and from San Venanzo, Rieti, Italy ( SV ), is orthorhombic with space group Pmam . Crystallographic data, given in the order ( Z ), ( TC ), ( SV ), are: a 0 = 23.416(5)/23.444(5)/23.428(20) Å, b 0 = 6.555(1)/6.553(1)/6.5…