Silicones sur terres cuites
no disponible
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。
Un mortier insecticide
No disponible
LV. The optical and electrical properties of single crystals of sodium niobate
The optical strains and dielectric constants of small single crystals of sodium niobate have been measured over the temperature range -190°c to +650°c. At room temperature the properties are consistent with an antiferroelectric structure, and for high fields applied perpendicular to the orthorhombic c axis, double hys…
Etch Patterns and Ferroelectric Domains in BaTiO3Single Crystals
It has been found that ferroelectric BaTi${\mathrm{O}}_{3}$ single crystals show a differential etch rate when etched in hydrochloric acid. The positive end of the electric polarization etches much faster than the negative one. Thus this phenomenon affords a valuable new tool for the investigation of the ferroelectric…
Theory of Ionic Ordering, Crystal Distortion, and Magnetic Exchange Due to Covalent Forces in Spinels
Elastic- and electrostatic-energy considerations are insufficient for an explanation of cation ordering between tetrahedral and octahedral sites in spinels. Tetrahedral, octahedral, and square covalent bonds are also important when cations are to be accommodated in these sites. The square bonds in octahedral sites can…
The crystal structure of Mn2Sb
The crystal structure of Mn2Sb has been re-examined. Rotation and Laue patterns from small fragments and patterns using powdered samples confirmed the published tetragonal structure with a ----4.08, c -----6.56 A. Large single crystals were grown to make possible a study of reflections from 00/, h00 and hhO planes. Re…
Anwendung der Halbleiter‐Theorie auf Probleme der heterogenen Katalyse
Abstract Es wird der Stand der heutigen Katalyse‐Forschung aufgezeigt und die gegenseitige Beziehung zu der Halbleiter‐Theorie herausgestellt. Nach Behandlung der Grundlagen der Randschicht‐Theorie der Chemisorption wird vor allem am Beispiel des N 2 O‐Zerfalls und der CO‐Oxydation der Mechanismus des wechselseitigen…
The Reactions of Two Diaryl Diselenides with Mercury(II) Chloride
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTThe Reactions of Two Diaryl Diselenides with Mercury(II) ChlorideEdwin S. Gould and Albert AmendolaCite this: J. Am. Chem. Soc. 1955, 77, 8, 2103–2104Publication Date (Print):April 1, 1955Publication History Published online1 May 2002Published inissue 1 April 1955https://pub…
Zur Komplexchemie der 2‐ und 3 wertigen Seltenen Erden Polarographische Untersuchungen an Europiumkomplexen
Abstract Unter Hinzuziehung spektroskopischer Ergebnisse werden für Äthylendiaminotetraessigsäure und o‐Cyclohexandiaminotetraessigsäure als Komplexbildner die Bildungskonstanten sowohl der Eu (III)‐ als auch der Eu (II)‐Komplexe aus polarographischen Messungen ermittelt und damit die Existenzbereiche der einzelnen Ko…
Low Temperature Heat Capacity and Entropy at 298.16°K. of Analcite
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTLow Temperature Heat Capacity and Entropy at 298.16°K. of AnalciteE. G. KingCite this: J. Am. Chem. Soc. 1955, 77, 8, 2192–2193Publication Date (Print):April 1, 1955Publication History Published online1 May 2002Published inissue 1 April 1955https://pubs.acs.org/doi/10.1021/j…
High Temperature Heat Contents of Some Titanates of Aluminum, Iron and Zinc
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTHigh Temperature Heat Contents of Some Titanates of Aluminum, Iron and ZincK. R. BonnicksonCite this: J. Am. Chem. Soc. 1955, 77, 8, 2152–2154Publication Date (Print):April 1, 1955Publication History Published online1 May 2002Published inissue 1 April 1955https://pubs.acs.or…
17—The Motion of Floating Fibres During Drafting of Worsted Slivers
The reasons for the acceleration of floating fibres, mentioned in a previous paper, are discussed here in greater detail. The paper indicates the importance of considering each fibre individually and shows that, when this is done, the predicted and observed fibre movements agree. The paper then goes on to discuss the…
The crystal structure of berthierite, FeSb2S4
The general arrangement of atoms in berthierite had been suggested in an earlier publication by solving the Patterson function P(xy), with the aid of the minimum function M8(xy). In this paper a report is given of the refinement of the structure. The intensities were measured by the M.I.T. modification of the Dawton m…
Preparation and Half Life of Carrier-Free Yttrium-90
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTPreparation and Half Life of Carrier-Free Yttrium-90M. L. Salutsky and H. W. KirbyCite this: Anal. Chem. 1955, 27, 4, 567–569Publication Date (Print):April 1, 1955Publication History Published online1 May 2002Published inissue 1 April 1955https://pubs.acs.org/doi/10.1021/ac6…
The polymorphism of cordierite and indialite
Optical and x-ray studies of synthetic and natural material of magnesium cordierite composition lead to the conclusion that there are five polymorphic modifications. It is proposed to restrict the name cordierite to the two pseudohexagonal forms (connected by high-low inversion relation) and to designate the two hexag…
A direct analytical test of the Flory‐Schulz distribution in nylon 6 type equilibrium polymers. Preliminary communication
Abstract The validity of the Flory‐Schulz distribution of chain length in equilibrium polymers produced from ϵ‐caprolactam and water (Nylon 6) over a DP range from ∼14 to ∼90 is tested by determination of the content of monomer (ϵ‐aminocaproic acid, ACA) by means of a chromatographic technique. Experiments show genera…
Experimental Study of the Mechanism of Thermoluminescence in Irradiated Sodium Chloride
The general configuration of the emission spectrum of synthetic NaCl crystals which had been irradiated with 7 × 105r of x-rays at room temperature and were then permitted to luminesce at 500°K was determined, and bands were located with maxima at 362, 418, 432, and 525 millimicrons. The glow curves for NaCl crystals…
Physical Limits of Glauconite Formation
ABSTRACT Available records indicate that the formation of glauconite requires marine water near normal salinity, reducing conditions, and appropriate source materials. It is favored by high organic content of the bottom sediments in which it forms, and by slow or negative sedimentation. It may form under a fairly wide…
Acid Catalysis in the Thermal Decomposition of Ammonium Nitrate
Experimental measurements of the kinetics of thermal decomposition of ammonium nitrate have been made in the temperature range from 443 to 553°K. The results indicate that the degradation of ammonium nitrate is an autocatalytic liquid-phase reaction, the rate of which is proportional to the product of the mass of salt…
Interaction of Methylene Deformation Frequencies in Paraffin Crystals II. A Theoretical Treatment of the Interaction of Vibrations
The splitting of the methylene deformation frequencies in crystals of n-paraffins is described in terms of interaction between nearest-neighbor molecules On the basis of a simplified model, the order of magnitude of the splitting may be accounted for Polarization behavior and changes occurring upon heating, cooling, a…