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 experimental information available from x-ray photoemission spectroscopy regarding the electron correlation energy $U$ of $3d$ and $4f$ electrons in solids is considered. It is found that $U$ is of the order of 7 eV for $4f$ electrons and \ensuremath{\sim} 2 eV for $3d$ electrons.
The thermal conductivity, electrical resistivity, and thermoelectric power of well-characterized, polycrystalline specimens of pure Co have been determined in the temperature range of 90 to 1250 K. Additionally, the measurements of the electrical resistivity have been extended to 1750 K, and the coefficient of thermal…
Cation self-diffusion coefficients have been obtained for MgO in an argon atomosphere over a temperature range 1000–2400°C from concentration gradients determined with the aid of mass spectrometry. The problems associated with use of the short-lived radioisotope 28Mg were avoided by employing the stable isotope 26Mg a…
The high-resolution x-ray-photoemission-spectroscopy (XPS) valence-band spectrum from a cleaved natural-diamond single crystal is reported. The absence of extrinsic structure allows a reliable comparison with band theory. The XPS molecular-orbital spectra of methane, silane, and germane are also given. The modulation…
The design and operation of a magnetocalorimeter for the highly accurate measurement of the enthalpy increase and magnetic properties of CMN over the range 0.0006 to 0.01°K are described. The essentials were as follows: A Pyrex calorimeter equipped with a Pt-9%W noninductively wound heater and carbon thermometers, and…
The pressure and temperature dependence of the refractive index and absorption edge have been measured for a group of amorphous semiconductors with average coordination number between two and four, all containing group-VI elements in twofold coordination (lone-pair semiconductors). Clear compositional trends are obser…
The theory of the thermal resistivity of dielectric crystals at ordinary and high temperatures in terms of anharmonic three-phonon interactions is reformulated. The resistivity is similar in form to that obtained by Leibfried and Schl\"omann, but larger by a factor of 6.8. The theory is then extended to crystals where…
For pt. I see abstr. A7013 of 1972. Expressions for the g-values and hyperfine structure parameters of Cu 2+ ions in tetragonally distorted tetrahedral sites are derived by including the effects of covalency, 4p mixing and the dynamic Jahn-Teller effect. The results are applied to Cu:Cs 2 ZnCl 4 where agreement with E…
The ESR spectra of several brown diamonds measured at 77 K show a central group of three equally strong lines, with two groups of six closely spaced anisotropic lines of equal intensity at about 30-40 G on either side of the central group. The central group of lines has double the intensity of the side lines. Spacings…
A simple method is proposed for calculating by hand the thickness of surface films using data obtained from the microprobe analyser. It is shown that, if one exploits the scaling properties of electron scattering distributions, a set of curves may be obtained representing the fraction of characteristic ionization prod…
A critical examination is presented of the available experimental evidence relating to the frequency dependence of the electrical conductivity of a wide range of disordered and amorphous semiconductors and insulators. It is pointed out that there is no justification for regarding these effects as true bulk phenomena,…
An experimental study of critical phenomena in thin ferroelectric films is presented which, for the first time, conclusively demonstrates that the polarization in thin films is drastically reduced as a result of depolarization effects. Other causes, like impurities, structural defects, and domain formation, which can…
The existence of a monoclinic phase of hydroxyapatite, Ca(2)(PO(4))(4)OH, has been confirmed, by single-crystal structure analysis (weighted "reliability" factor = 3.9 percent on |F|(2)). The structure has space group P21/b, a = 9.4214(8) angstroms, b = 2a, c = 6.8814(7) angstroms, and gamma = 120 degrees , and is ana…
The formation of the polyoctamolybdate ion [Mo 8 O 6- ]n results from two condensation principles. First the octamolybdate ion [H 2 Mo 8 O 28 ] 27 6- is formed by stepwise aggregation according to the condensation mechanism formerly proposed 2 . This species is subjected to a polycondensation resulting in an octamolyb…
Summary In this work, the effect of the corrosion accelerating substances sulphur dioxide and nitrate, which may be present in foods as residues was investigated. The amount of dissolved tin and iron were taken as the corrosion criteria. Sulphur dioxide was found to act as a corrosion accelerator, in an acid medium of…
Abstract Infrared frequency band assignments are given for Group IV A polyesters and polyoxides of the below form: magnified image The infrared band assignments are in general agreement with those reported for the corresponding mono‐ and diesters and oxides. Either or both (d‐p)π bonding or sigma electronic inductive…
Abstract A previously suggested new theoretical model for the extension of the charge density of 3d electrons of atoms of ferromagnetic metals of the iron group (in comparison to that in a free atom) and a concept of a neutral atom in metals is considered and on the same basis a calculation has been made for the elect…
The necessity and difficulty of developing an ideal formulation of a chemical coating for optimum man-made fiber processing on textile equipment under varying conditions is stressed. In the absence of such a coating, the fiber has little economic value. The phrase "spin-finish" is defined. The various compounds chiefl…
Summary Phosphate minerals of the plumbogummite group were tentatively identified in a strongly weathered and leached New Zealand soil formed from granite by comparing changes in inorganic phosphate fractions, after calcination, of a soil sample with those occurring in Christmas Island rock phosphate. This identificat…
Relaxation processes were studied in bulk B 2 O 3 glasses compacted under hydrostatic pressures up to 21 kbars at room temperature. Measurements of room‐temperature density and refractive index at 1 atm revealed that (1) more than one ordering parameter is required to describe observed time‐dependent volumetric behavi…