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。
A thermodynamic and high‐temperature X‐ray diffraction study was performed on polycrystalline nonstoichiometric BaTiO 3 . The oxygen composition was measured from 940° to 1215°C at O 2 partial pressures between 10 −10 and 10 −21 atm by a thermogravimetric technique. The isothermal weight change data exhibit a two‐slop…
The extensional moduli and Poisson's ratios of cold-drawn low-density polyethylene sheets have been determined by direct observation of the changes in dimensions under load of electron microscope grids printed on the surfaces of the sheets. The highly drawn sheets show incompressible behavior only for vanishingly smal…
Abstract Nach einem kurzen Überblick über bisherige Untersuchungen an Epoxidharz–Dizyandiamid‐Systemen, wurde der Reaktionsverlauf eines handelsüblichen dizyandiamidhärtenden Epoxidharzes mittels Ultrarotspektroskopie verfolgt und mit den Ergebnissen früherer anderer Methoden am gleichen System verglichen. Dabei ergab…
Abstract Die Infrarot‐ und Ramanspektren von Thioharnstoff‐Einkristallen bei 300 und 120°K werden mit polarisierter Strahlung aufgenommen. Zusätzlich werden die Spektren der deuterierten Verbindung an polykristallinen Proben und die Fern‐Infrarot‐Spektren an pulverförmigen Proben gewonnen. Damit ist eine vollständige…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTSelf-consistent-field wave functions of P2 and PO, and the role of d functions in chemical bonding and of s-p hybridization in N2 and P2Robert S. Mulliken and Bowen LiuCite this: J. Am. Chem. Soc. 1971, 93, 25, 6738–6744Publication Date (Print):December 1, 1971Publication Hi…
Abstract The small‐angle light scattering (SALS) theory for optically anisotropic spheres and disks is examined in depth. An error is found in the existing sphere equations. The correct form of the equations is identified and then experimentally verified for dilute starch suspensions. Increased concentrations and soli…
Abstract Li-, Na-, K- and Ca-saturated Wyoming montmorillonites have been prepared and used to obtain Li,Na-, Li,K-, and Li,Ca-montmorillonites with a range of Li contents. These were heated at 220°C for 24 hr, causing the Li + ions to migrate mainly into the layer structure and leaving varying amounts of Li + , Na +…
The dislocation arrangements in single crystals of Cu 2% at. Al and Cu 10% at. Al deformed into stage II of the work-hardening curve have been observed by transmission electron microscopy. The observations are described and discussed in relation to the theories of stage II work-hardening. It is concluded that the beha…
The drift of charge carriers in thin vitreous films of arsenic triselenide has been examined by a transit time technique. The specimens used were prepared by cooling from the molten state, rather than by evaporation. Electron mobility measurements were found to be impractical, the mobility being estimated as less than…
The article deals with the distribution and ecology of the Thalassionema, Asterionella, Amphicampa, Peronia, Eunotia and Actinella species known in Finland.
Collagen has been extracted from the skin of dermatosparaxic calves and fractionated by acrylamide-gel electrophoresis and CM-cellulose chromatography. This collagen contains in large proportion two additional types of α-chains, P-α1 and P-α2. The first, P-α1, ressembles α1, of a collagen extracted from the skin of a…
The X-ray diffraction lines from twelve powder samples of iron and high-speed steel with various mesh sizes and chemical compositions were measured and the data analysed using the centroid and variance as measures of line position and width. Values of lattice parameter, apparent crystallite size and mean lattice strai…
Abstract Clay fractions in soils from a transect of the Mazama ash deposit (6600-yr-old) contained more than 80% amorphous material. Instrumental neutron activation analysis was used to compare the trace element composition of the soil clay with the unweathered volcanic glass. The clay fractions had only 10% as much N…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTPolar Tautomer Dimerization of Ionic Arylazonaphthols in WaterAlan Monahan, Allen DeLuca, and Anthony WardCite this: J. Org. Chem. 1971, 36, 24, 3838–3842Publication Date (Print):December 1, 1971Publication History Published online23 December 2002Published inissue 1 December…
Abstract A variety of stevensite was collected at the Obori mine, Yamagata Prefecture, Japan. Analysis shows close agreement with published data for stevensite. Chemical composition: SiO 2 52·76%; A1203 trace; Fe203 0·38%; MgO 23·67%; MnO 1·57%; CaO 2·19%; Na 2 O 0·37%; K 2 O 0·00%; H 2 O + 6·52%; H 2 O − 12·38%; Tota…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTElectron transfer in the type II photoelimination of .alpha.-aminoacetophenonesAlbert Padwa, William Eisenhardt, Robert Gruber, and Deran PashayanCite this: J. Am. Chem. Soc. 1971, 93, 25, 6998–7005Publication Date (Print):December 1, 1971Publication History Published online…
Abstract The radiation‐induced copolymerization of chlorotrifluoroethylene with ethyl vinyl ether was investigated in the liquid phase at 20 and −78°C over a wide range of monomer compositions. A copolymer was obtained in which the monomers alternate with regularity along the polymer chain over the entire range of mon…
In impact-produced spall fracture, a material undergoes drastic dynamic precompression immediately prior to the time of fracture. In this paper a technique is described for varying the precompression stress wave magnitude σc relative to the magnitude σr of the rarefaction wave, which produces the spall, in the range o…
Abstract— Three different types of photomotion reactions, photokinesis, photo‐topotaxis and photo‐phobotaxis, have been investigated in the diatom Nitzschia communis . In photokinesis the active light appears to be absorbed by the photosynthetic pigments. Apparently, the acceleration of movement by light is due to an…
The anisotropic threshold energy for atomic displacements and the displacement cascade process in electron-irradiated pyrolytic graphite are studied in the energy range from 0.12 to 1.0 MeV at three different temperatures by observing the a -axis electrical resistivity increases. The threshold energy T d is represente…