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 new formulation of the single‐polynomial analysis is presented, in which the electron density profile is assumed to begin with a flat base at a height equal to the lowest measured virtual height. This formulation gives a more accurately defined profile with only a small number of points and agrees with the assumptio…
M. J. Broadhurst, R. Grigg and A. W. Johnson, J. Chem. Soc. D, 1969, 23 DOI: 10.1039/C29690000023
The early stages of the shell regeneration in Helix pomatia have been studied by electron microscopy. Within 1 hour after the removal of a piece of shell, minute crystals of CaCO 3 appear in the injured area. Electron diffraction study showed these crystals to be aragonite. Calcite crystals were also present at later…
Results are presented of parallel calorimetric and dilatometric experiments on several meltcrystallized polyethylenes, with various thermal histories, over the range –35°→ liquidus. Enthalpic and weight fraction degrees of crystallinity are in good agreement up to 60°C, where direct comparison with n-alkane data is po…
O. A. Y. Jackson, Fitting a Gamma or Log-Normal Distribution to Fibre-Diameter Measurements on Wool Tops, Journal of the Royal Statistical Society. Series C (Applied Statistics), Vol. 18, No. 1 (1969), pp. 70-75
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTIncorporation of zinc ion into a synthetic water-soluble porphyrinT. Peter Stein and Robert A. PlaneCite this: J. Am. Chem. Soc. 1969, 91, 3, 607–610Publication Date (Print):January 1, 1969Publication History Published online1 May 2002Published inissue 1 January 1969https://…
AGGREGATE TEST METHODS TO IDENTIFY FROST-SUSCEPTIBLE PARTICLES IN CONCRETE AGGREGATES ARE EVALUATED. TWO APPROACHES TO THE PROBLEM OF IDENTIFYING FROST-SUSCEPTIBLE AGGREGATE PARTICLES WERE FOLLOWED. RELATIVELY HOMOGENEOUS AGGREGATE FRACTIONS WERE TESTED IN CONCRETE UNDER SIMULATED FIELD CONDITIONS, TO (1) DEVELOP A RA…
Abstract New, bifunctional, bridgehead‐substituted triptycenes were synthesized and used to prepare a series of triptycene polymers, including polyesters, polyamides, polyurethanes, and a polyoxadiazole. Certain of these partially aliphatic polymers were thermally stable. Clear and colorless films were obtained in som…
Complexes of the general type CuLx(CF3CO2)2, where x= 2 or 4, L = pyridine, mono-and di-substituted pyridines, quinoline, or isoquinoline, have been prepared and characterised by spectroscopic methods. The complexes are six-co-ordinate with the trifluoroacetate group involved in either mono-or bi-dentate attachment to…
Abstract A study of the swelling of Acala 4‐42 cotton in aqueous alkalis and acids has been carried out. The degree of swelling of the cotton in the reagents has been indicated by measurement of the variations in width of the cotton at its widest point. The nature of the swelling process whether interfibrillar or intr…
When iron is oxidized at 500°C in oxygen at 10 Torr, blisters develop in the scale. This does not occur when the iron is oxidized at 500°C in oxygen at 700 Torr, nor when the iron contains carbon as a cementite precipitate. It appears that the iron oxide scale blisters if cation vacancies can accumulate at the oxide‐m…
Some apparently penta-co-ordinate mononitrosyls, prepared by the reaction of nitric oxide with the high-spin compounds, NN′-ethylenebis(salicylideneiminato)iron(II) and its 5-Me-, 3-NO2-, 5-Cl-, 4-Cl-, and 5-NO2-substituted derivatives, have three unpaired electrons at room temperature. The magnetic moment of the unsu…
Abstract In this article an investigation is made of deformation of the molecular crystal due to electronic excitation. It is shown that in a three‐dimensional crystals at a sufficiently large resonance interaction between molecules the states of free excitations with positive effective mass correspond to minimum of t…
Two melting reactions, (i) CaCO_3 + Ca(OH)_2 = liquid and (ii) CaCO_3 + Ca(OH)_2 + vapor = liquid, have been extended from 4 kb to 40 kb using piston-cylinder \napparatus. Points measured for reaction (i) are: 655°C at 4 kb, 659°C at 15.5 \nkb, 662°C at 25 kb, and 666°C at 40.7 kb; and for reaction (ii): 630°C…
Abstract In 1959, Hyde and Wehrly described an emulsion polymerization of permethylcyclosiloxanes. This unique example of an emulsion polymerization proceeding via an ionic mechanism involved base catalysis with a cationic surfactant. An analogous acid‐catalyzed anionic emulsion polymerization has now been developed w…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTQuenching of pyrochlorophyll fluorescence by nitro compoundsGilbert R. SeelyCite this: J. Phys. Chem. 1969, 73, 1, 125–129Publication Date (Print):January 1, 1969Publication History Published online1 May 2002Published inissue 1 January 1969https://pubs.acs.org/doi/10.1021/j1…
The syntheses of tristetrachlorobenzene-1,2-dithiolene complexes [M(S2C6Cl4)3]z(z=–2, M = Ti, V, Cr, Mn, Fe and W; z= 1, M = V, W, and Re; z= O, M = W) are reported. The preparation of [W(S2C6H3Me)3]– and of a manganese tristoluene-dithiolene species are described. Voltammetric studies of these tris-tetrachlorobenzene…
The adhesion between glass or oxidized Si substrates and evaporated gold films in combination with an adherent intermediate layer of Ta, Si, Ge, or Cr has been investigated. The experimental results regarding changes of adhesion as a function of the relative thickness of the Au and underlayer films as well as time, en…
The vibrational spectrum of crystalline Re2O7 is discussed from the point of view of a factor-group analysis. The Raman spectrum changes radically on passing from the solid state to the gaseous or liquid states. The changes observed reflect the presence of a monomeric species in the gaseous or liquid state, compared w…
Abstract Three different emulsion polymerization techniques, the batch (B), monomer addition (M Add), and emulsion addition (E Add) procedures were studied. Rates of polymerization indicated that the B reacted more rapidly than either the M Add or E Add. This was related to the lower monomer concentration present in t…