Materials Literature
文献浏览
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。
Dependence of Mechanical Strength of Brittle Polycrystalline Specimens on Porosity and Grain Size
An empirical equation form, approximating the apparent dependence of the strength of brittle polycrystalline specimens on the combined effect of porosity and grain size, has been developed from concepts and data in the literature. The form is shown to be applicable to data for thoria and chromium carbide specimens.
Total Photoelectric Cross Sections of Copper, Molybdenum, Silver, Tantalum, and Gold at 662 kev
The total photoelectric cross sections of copper, molybdenum, silver, tantalum, and gold have been measured at 662 kev. A highly collimated beam of gammas from a Cs-137 source impinged upon a thin disk of a target material. Photoelectrons from a target were detected by a plastic scintillator subtending very nearly $4\…
Crystal Structure of the Ferroelectric Phase of(Glycine)3·H2SO4
Ferroelectric ${(\mathrm{glycine})}_{3}$\ifmmode\cdot\else\textperiodcentered\fi{}${\mathrm{H}}_{2}$S${\mathrm{O}}_{4}$ crystallizes at room temperature in the monoclinic system with $a={9.41}_{7}$ A, $b={12.64}_{3}$ A, $c={5.73}_{5}$ A, $\ensuremath{\beta}=110\ifmmode^\circ\else\textdegree\fi{}{23}^{\ensuremath{'}}$;…
Clay Minerals in Playas of the Mojave Desert, California
Montmorillonite, illite, chlorite, and kaolinite in the playas of southern California are traceable directly to the source areas surrounding the basins. No evidence found in this investigation suggests that these clay minerals are unstable in the sodic or calcic saline lake environment, but this conclusion may not be…
The crystal structure of proto-enstatite, MgSiO3
Proto-enstatite, at room temperature, is orthorhombie with 8 units of MgSiO3 in a cell of dimensions a ----9.25, b ----8.74, c = 5.32 A, pseudo space group Pbcn. The atomic coordinates of the pseudo space group were determined from X-ray powder data. The SiO3 chain is fully extended. One of the Mg atoms has an irregul…
The crystal structure of a simple rhombohedral form of boron
A new modification of boron, resulting from the pyrolytic decomposition of BI z on a heated surface (800 C. to 1100 C.), has been found to have a simple rhombohedral structure, with a 0 = 5.057 /~ and c~ = 58.06 , space group R3m, Z ----12. The atomic parameters have been obtained from a single crystal using the prece…
The crystal structure of baddeleyite (monoclinic ZrO2)
The structure was determined and refined by use of Pa t te rson and Fourier projections on the three faces of the uni t cell. The seven shortest Zr-O separations in the coordination polyhedron around each zirconium range from 2.04 to 2.26 A; since the next nearest Zr-O separat ion is 3.77 ~ , the coordination number o…
The Influence of Activators on the Vulcanization Process. II. The Influence of Zinc Oxide on the Structure of Vulcanizates
Abstract The influence of zinc oxide and stearic acid on the structures of vulcanizates was traced in stocks with mercaptobenzothiazole by means of the kinetics of swelling. It was found that zinc oxide in the presence of stearic acid has a marked influence on the rate and degree of crosslinked network formation in vu…
Reaction of Hydrazine Hydrate and Phenylhydrazine with Malononitrile
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTReaction of Hydrazine Hydrate and Phenylhydrazine with MalononitrileTADASHI SATOCite this: J. Org. Chem. 1959, 24, 7, 963–966Publication Date (Print):July 1, 1959Publication History Published online1 May 2002Published inissue 1 July 1959https://pubs.acs.org/doi/10.1021/jo010…
Thermal‐oxidative degradation of poly(ethyl acrylate)
Abstract The thermal‐oxidative degradation of films of poly(ethyl acrylate) about 35 μ thick were studied in the temperature range of 80 to 120°C. The degradation was followed by determining intrinsic viscosity changes, absorption of oxygen, and production of titratable acidity in the polymer. From viscosity results a…
24—AN EXPERIMENTAL STUDY OF THE GEOMETRICAL STRUCTURE OF SINGLE YARNS
Results of measurements of retraction as a function of twist are given for yarns produced by continuous twisting processes, as opposed to the twisting of a fixed length. These are compared with Tattersall's2 earlier work and also with the predictions of Treloar's1 theory. When continuous twisting methods are used, the…
The saturation magnetostriction of ferromagnetics
(1959). The saturation magnetostriction of ferromagnetics. Advances in Physics: Vol. 8, No. 31, pp. 252-291.
The inhibition of the corrosion of iron in neutral and alkaline solutions. I
Abstract The potentials at which iron is converted into anhydrous cubic oxide in certain inhibitive solutions have been measured and it has been shown that these potentials are more negative than the potentials acquired by unpolarised specimens immersed in the solutions for 3 days. It is suggested that when iron, carr…
Effects of gamma radiation on some physical properties of polytetrafluoroethylene resin
Abstract Effects of gamma radiation on the properties, such as melt viscosity, elastic modulus above the melting point, creep fracture time above the melting point, density, and the degree of crystallinity by x‐ray diffraction, of polytetrafluoroethylene resin were studied. When exposed to the radiation from a Co 60 g…
The effect of the sorption process on the dynamic rigidity modulus of the wool fiber
Abstract Using a torsion pendulum, measurements have been made of the dynamic modulus of rigidity of wool fibers during the process of sorbing or desorbing water (from the vapor phase). Anomalous behavior is observed, with low values of rigidity which cannot be accounted for in terms of equilibrium data. It appears th…
Crystallization kinetics of isotactic polypropylene
Abstract Crystallization kinetics of Hercules polypropylenes were studied between 133 and 155 ° C. using dilatometers. The crystallization rates of these samples became too rapid below 133 ° C. for accurate dilatometric measurements. One sample (A) was a commercial sample containing stabilizer and 9% extractable polym…
Systematics in the Chemistry of the Boron Hydrides
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTSystematics in the Chemistry of the Boron HydridesR. W. Parry and L. J. EdwardsCite this: J. Am. Chem. Soc. 1959, 81, 14, 3554–3560Publication Date (Print):July 1, 1959Publication History Published online1 May 2002Published inissue 1 July 1959https://doi.org/10.1021/ja01523a…
Experimental and theoretical study of kinetics of bulk crystallization in poly(chlorotrifluoroethylene)
The rate of isothe rm al bulk crystalli zation of poly (e hloro trifluoroethylene) , 2'm = 221 C, was measured from 170 0 to 200 0 C. The intrinsic bulk cr ystallization, which acc uraLe ly ~o llow e d a n n= 2 la\,:, was. shown t o be a res ult of the i~lj ect ion of primary nu clei spora di cally III Lime, with on e…
Studies on the orientation phenomena by fiber formation from polymer melts. Part I. Preliminary investigations on polycapronamide
Abstract The problem of the mechanism of macromolecule orientation occurring in the formation of fibers from polymer melts has been qualitatively analyzed. As a result of birefringence, x‐ray, and spinning stress investigations carried out on polycapronamide fibers, the main parameters determining orientation have bee…