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Regularities in the influence exerted by mineralising agents on the manufacturing process of white Portland cement clinker
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Construction and exploitation possibilities of the automatic apparatus for the determination of carbonates, Holderbank system
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Thermal and X-Ray Diffraction Studies of the NaNbO3–KNbO3 System
Thermal and x-ray diffraction measurements on compositions from the system NaxK1−xNbO3 have revealed the presence of phase boundaries at approximately 82.5, 67.5, and 52.5 mole × NaNbO3 at 25°C, in addition to one very near the NaNbO3 end member. The optimum piezoelectric properties in this system are apparently assoc…
DISTRIBUTION OF PYROPHOSPHATE‐EXTRACTABLE IRON AND ORGANIC CARBON IN SOILS OF VARIOUS GROUPS
Summary Potassium pyrophosphate (0.1 m ) removes very little Fe from crystalline Fe oxides at pH 10, but peptizes finely divided hydrous amorphous oxides and organic matter in soils. Fe and C contents of extracts from each horizon of twenty‐six British soil profiles show distinctive patterns, independent of the residu…
Evidence for Itinerantd-Electron Ferromagnetism
We describe here a metallic ferromagnetic system ${\mathrm{Fe}}_{1\ensuremath{-}x}{\mathrm{Co}}_{x}{\mathrm{S}}_{2}$ and ${\mathrm{Co}}_{1\ensuremath{-}x}{\mathrm{Ni}}_{x}{\mathrm{S}}_{2}$ that appears to have a single doubly degenerate band. The electrons in the band are itinerant as manifested by metallic electrical…
Magnetic Field Effect on Triplet Exciton Quenching in Organic Crystals
The rate of quenching of triplet excitons by paramagnetic impurities in anthracene crystals at room temperature is found to be magnetic-field dependent. A theory of the effect is presented.Received 17 July 1968DOI:https://doi.org/10.1103/PhysRevLett.21.609©1968 American Physical Society
Mollusk Shell: Daily Growth Lines
Ridges forming the concentric sculpture on the shells of laboratory-grown specimens of Pecten diegensis Dall show daily periodicity. Missing growth lines account for all scatter in the data, so that the maximum, not the average, line count is most representative. The variation in spacing between growth lines can be co…
Graphite ablation in high-pressure environments
Abstract : A performance analysis of the thermochemical/thermomechanical behavior of graphite is made extending present analysis procedures to include the allotropic features of bulk graphite. The analysis comprises a complete definition of graphite sublimation, and formulates a model for mechanical erosion based on e…
Crystallite Orientation Distribution in Biaxially Oriented Polyethylene
The procedure of Roe for describing the crystallite orientation in polycrystalline samples having general texture is tested using two samples of biaxially drawn polyethylene. An automated four-circle diffractometer was used to obtain 12 pole figures (4332 fixed points) for the film having stretching ratios 3.0 × 2.0,…
Bis(Thiosemicarbazone) and Other Nitrogen and Sulfur Ligated Complexes of Copper(II)
We have measured the electron paramagnetic resonance and optical absorption properties of several complexes of copper(II) in which the ligands of the copper atom are two nitrogen and two sulfur atoms. Chelate structures varying from two saturated rings to a three-condensed-ring pseudoaromatic system have been explaine…
Reductions with sulfurated borohydrides. I. Preparation of sulfurated borohydrides
Sodium borohydride reacts with sulfur at room temperature in the presence of appropriate organic solvents to give a sulfurated borohydride: NaBH 2 S 3 . The formulation of this hydride has been established by infrared, nuclear magnetic resonance, and elementary analysis. Thermal decomposition and hydrolysis are report…
A NEW ELECTRIC-FIELD-CONTROLLED REFLECTIVE OPTICAL STORAGE EFFECT IN MIXED-LIQUID CRYSTAL SYSTEMS
A new reflective optical storage effect has been found in mixtures of certain nematic liquid crystals and cholesteric liquid crystals. When subjected to a dc field, the initially clear material becomes milky white and remains in this state when the field is removed. The material can be rapidly switched back to its cle…
Inadequacies of Viscosity Theories for B2O3
The viscosity of B2O3 glass was measured from 1010–1014 P by the fiber-elongation method and found to be Arrhenius with an activation energy of 94 kcal/mol. These new data were combined with previously reported rotation data (101–1010 P) and gave a smooth plot. The complete viscosity data were used to test the equatio…
Optical Properties of VO2between 0.25 and 5 eV
The optical constants of V${\mathrm{O}}_{2}$ have been determined between 0.25 and 5 eV both below and above the semiconductor-metal transition temperature ${T}_{t}=340\ifmmode^\circ\else\textdegree\fi{}$K. Reflectivity and transmission spectra have been measured on both single crystals and than films. The reflectivit…
Generalized Susceptibilities and Magnetic Ordering of Heavy Rare Earths
The generalized magnetic susceptibilities, $\ensuremath{\chi}(\stackrel{\ensuremath{\rightarrow}}{\mathrm{q}})$, have been calculated along the line $\ensuremath{\Gamma}$ to $A$ for the heavy rare-earth metals, Gd, Dy, Er, and Lu, using energy bands previously calculated by Keeton and Loucks. The initial ordering peri…
Radiative Decay of Coulomb-Stimulated Plasmons in Spheres
We have studied the excitation of plasmons by energetic electrons, and their subsequent decay, in small spheres. We estimate that plasma decay light from electron bombardment of small, randomly distributed metal spheres suspended in a dielectric medium may be emitted with intensity comparable with that found in experi…
Atomic Displacement Relationship to Curie Temperature and Spontaneous Polarization in Displacive Ferroelectrics
The phase transition from nonpolar to polar in displacive ferroelectric crystals is accompanied by the displacement $\ensuremath{\Delta}z$ of certain atoms from their higher-temperature symmetry positions. A study of all displacive ferroelectrics in which atomic positions have been determined has shown that a fundamen…
Polyolefins containing intra‐molecular crosslinks
Abstract By treating α‐olefins/allylsilane copolymers with alkali/alcohol mixtures, ≡SiH bonds of allylsilane units are transformed into ≡SiOSi≡ crosslinking bonds. Soluble or insoluble polymers are obtained depending on whether copolymers to be treated are suitably dissolved or not dissolved in the alkali/alcohol…
Schlagfestes polystyrol auf acrylesterbasis, ein beitrag zur struktur schlagfester polystyrole
Abstract Wegen des Olefincharakters der Butadienpolymeren ist die Alterungsbeständigkeit von schlagfestem Polystyrol unbefriedigend. Alle Versuche, schlagfeste Polystyrole mit gesättigten Elastomeren auf die übliche Art herzustellen, führten nicht zum Ziel. Es wird über Versuche zur Darstellung von schlagfestem Polyst…