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。
Results of luminescence studies on chelates of La3+, Sm3+, Eu3+, Gd3+, Tb3+, Dy3+, Tm3+, Yb3+, and Lu3+ are reported. It is shown that the intramolecular energy transfer efficiency is a sensitive function of the relative positions of the resonance energy levels of the ions and the metastable triplet states of the comp…
Abstract Zinc whiskers and platelets with their largest faces in the basal plane and thin enough (~½μ) to be transparent to 100 kV electrons were strained in tension inside the electron microscope and the nucleation and growth of twins observed by the transmission technique. These observations were then related to the…
A calculation of the influence of electron exchange on the dispersion relation of a high-density electron gas at 0\ifmmode^\circ\else\textdegree\fi{}K is described. The result is compared with those obtained by various authors using different methods.
Low-energy electron-diffraction and secondary electron-emission measurements have been made on (111) and ($11\overline{1}$) surfaces of GaSb and (100) surfaces of InSb. To account for the diffraction patterns observed both for these materials and previously for Ge and Si, a general model for (111) surfaces of diamond-…
Abstract The clay mineralogy of a soil profile developed in a New England glacial till has been studied to a depth of 55 in. Degraded soil micas, probably produced by weathering, have been chloritized by both iron and aluminum hydroxide complexes. Aluminum and iron determinations and X-ray analyses indicate that iron…
The energy relations existing between the congruently melting compounds Li 2 O ‐2B 2 O 3 , Na 2 O–2B 2 O 3 , Na 2 O‐4B 2 O 3 , and K 2 O‐4B 2 O 3 and their glasses have been determined for the temperature range 25° to 1100°C. High‐temperature heat‐content, entropy, and heat of solution data are given for both the glas…
Abstract The majority of, but not all, bundles of bacterial cellulose microfibrils show a characteristic left‐handed twist which has a pitch of about 1 μ. The remainder show no apparent coiling. The twist must reflect an internal strain in the component microfibrils which may be due to a slight progressive molecular a…
Several types of failure observed in tin plate containers are described in terms of tin-steel potential and current relationships. The effect of Sn++ on potentials and polarization of tin and steel electrodes in deaerated 1N HCl and 0.1M citrate buffer is shown to be important to proper design of electrochemical test…
A study has been made of the effect of oxygen on the intensity of absorption in the green or ``fluctuation'' bands by the gas phase in equilibrium with B2O3(l). The reaction which forms the substance responsible for the bands from B2O3(l) in the presence of oxygen was found to be 70 kcal/mole endothermic, in the range…
Measurements of the thermionic emission as a function of temperature and the photoelectric yield as a function of the photon energy in the range from 2.5 ev to 11.5 ev have been made on magnesium oxide in the form of thin films, powders, and single crystals. The thermionic emission measurements indicate that the posit…
Much available chemical evidence supports the hypothesis that covalent cross-linking is the best way to improve the resilience of cellulosic fabrics. This paper reviews the theories relating physical properties to cross-linking in rubbery polymers and shows that they apply in some qualitative aspects to cellulose. Par…
The crystal structure of Na 2 504 .10H 200, has been determined to explain the entropy which remains at low temperatures.This substance is monoclinic, space group P2 1 /c, with a =I.1.51 A. , b 10. 38 A. , c 12. 83 A,, each 0.01 A., 3 = 107 0 4511± 10 1 , Z = 4.The corresponding compounds with S replaced by Cr, Se, Mo…
The prisms in the shell of Mytilus edulis Linné are calcite needles. Their small size and their thin conchiolin cases distinguish them from the prisms of many other species of mollusks. These Mytilus prisms have been studied with the electron microscope. The material consisted of positive replicas of surfaces of the p…
The above title was used (Luder and Sheldon, 1955) to describe a family in which a renal tubular reabsorption defect involving glucose and amino acids appeared in three successive generations (female twins then aged 5, their father and his father). The purpose of this communication is to correct the impression given i…
A new type of dislocation motion, called 'conservative climb', has been observed in zinc platelets deformed in tension inside an electron microscope. Circular, prismatic dislocation loops are often forced to climb out of their glide cylinders by their repulsive interaction with edge dislocations. It is observed that t…
Experimental evidence is presented for the proportionality between secondary electron yield and the energy dissipated by electrons near the surface of a solid. Using measurements of the energy carried away by electrons transmitted and reflected from thin foils of aluminum and carbon, the energy dissipated in an increm…
It is shown experimentally that backscattered electrons emitted from solids under electron bombardment contribute significantly to the observed secondary yield, even for the case of low backscattering coefficients. Thus, it was found that in Al with a backscattering coefficient of only 0.14, about 40% of all secondari…
The enthalpies of mixing in binary liquid alkali nitrate systems have been measured, and are all negative. It is found that the magnitude of the molar mixing enthalpy (ΔHM) increases in a regular fashion with increasing difference in size between the two participating cations, according to the following approximate re…
Views Icon Views Article contents Figures & tables Video Audio Supplementary Data Peer Review Share Icon Share Twitter Facebook Reddit LinkedIn Tools Icon Tools Reprints and Permissions Cite Icon Cite Search Site Citation E. C. Subbarao; Ferroelectricity in Mixed Bismuth Oxides with Layer‐Type Structure. J. Chem. Phys…
The pulse-height distribution at the output of an electron multiplier structure for a single electron input has been calculated assuming a Poisson distribution at each stage. Graphs are given which illustrate the change in pulse-height distribution as a function of the number of stages. This has been done for intersta…