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Influence of alkalis on the properties of cement and Portland cement clinker

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Control of fresh concrete

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Contribution to the determination of the expanding properties of ceramic raw materials

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Bibliografía

Considerations on the accelerated resistance testing of cement

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Natural and controlled expansion of expanded clays for the production of lightweight aggregates

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Chemical control in the cement industry. Its importance

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Standardization of cement. Notes and explanations on the revision of the German cement standard DIN 1164, June 1970

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Etude en microscopie electronique du glissement pyramidal {1122} 〈1123〉 dans le magnesium

Electron Microscope Study of Pyramidal Slip {112} 〈113〉 in Magnesium We have investigated {112} 〈113〉 pyramidal slip in magnesium whose CRSS exhibits an anomalous dependence on temperature and increases between 270 and 375 K. Typical dislocation configurations were investigated by TEM in various temperature ranges. A…

Aggregation of meso-substituted water-soluble porphyrins

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTAggregation of meso-substituted water-soluble porphyrinsRobert F. Pasternack, Peter R. Huber, P. Boyd, G. Engasser, L. Francesconi, E. Gibbs, P. Fasella, G. Cerio Venturo, and L. deC. HindsCite this: J. Am. Chem. Soc. 1972, 94, 13, 4511–4517Publication Date (Print):June 1, 1…

Serially Deposited Amorphous Aggregates of Hard Spheres

Aggregates of several thousand equal hard spheres were constructed by depositing additional spheres, one at a time, at surface sites on a small seed cluster, placing each new sphere in contact with three already present and not moving it afterward. Always choosing the site closest to the center of the original seed re…

Phase Analysis in Zirconia Systems

Linear calibration curves were developed for determining the content of free ZrO 2 in partially stabilized zirconia ceramics by X‐ray diffraction techniques. Two methods were studied. The matrix method, in which free ZrO 2 was considered to be distributed in a matrix (the cubic phase), gave approximately equal mass ab…

Study of Tautomerism by Nuclear Magnetic Resonance Spectroscopy

The present review describes the contribution of NMR to the study of prototropic tautomerism of various types, with the exception of keto-enol tautomerism, which was dealt with in an earlier review. The bibliography contains 221 references.

Observation of Second Sound in Bismuth

We have observed the transition from ballistic to second sound to diffusive propagation of heat (phonon) pulses in the semimetal bismuth in the temperature range of 1.2 to 4.0 K. The saturated second-sound velocity is found to be independent of orientation and has a a value of (0.78\ifmmode\pm\else\textpm\fi{}0.05)\if…

ac Conductivity of Glasses

We investigate the ac conductivity of glasses due to atomic and electronic hopping between sites with random space and energy separations. Several examples are considered including the structural model of glasses recently introduced by Anderson, Halperin, and Varma, and by Philips. We find that glassy materials should…

Raman scattering and theoretical studies of Jahn—Teller induced phase transitions in some rare-earth compounds

Abstract The rare-earth crystals DyVO4, DyAsO4 and TbVO4 undergo structural phase transitions at 14, 12 and 34 K respectively induced by a cooperative Jahn-Teller effect. An experimental investigation of the phase changes has been made using Raman scattering methods. For purposes of comparison, the Raman spectra of Dy…

Charge Localization at Metal-Insulator Transitions inTi4O7andV4O7

Single-crystal x-ray investigations reveal charge localization in the insulating phases of ${\mathrm{Ti}}_{4}$${\mathrm{O}}_{7}$ and ${\mathrm{V}}_{4}$${\mathrm{O}}_{7}$. Chains of ${M}^{3+}$ and ${M}^{4+}$ sites run parallel to the pseudorutile $c$ axis, whereas the metal valences are disordered in the metallic phase…

Relation between pH and viscosity of some poly(alkylvinylpyridine N‐oxides) in aqueous solution

Abstract The variation with pH of the viscosities of aqueous solutions of the following polyvinylpyridine oxide derivatives has been studied, viz. atactic poly(2‐vinylpyridine 1‐oxide), poly(2‐methyl‐6‐vinylpyridine 1‐oxide), poly(3‐methyl‐2‐vinylpyridine 1‐oxide), poly(5‐ethyl‐2‐vinylpyridine 1‐oxide), poly(4‐vinylpy…

Atomic and magnetic structure of the Heusler alloys Ni2MnSb, Ni2MnSn, and Co2MnSn

Saturation magnetization, X-ray and neutron diffraction measurements were made on ferromagnetic alloys in the compositions Ni2MnSb, Ni2MnSn, and Co2MnSn. The compounds investigated have a crystallo-chemical structure of L21 type, with a partial disorder among NiSb atoms in the case of Ni2MnSb and Ni(Co)‒Mn atoms in t…

Structure of OrthorhombicV0.95Cr0.05O2

A structure determination of the orthorhombic phase of ${\mathrm{V}}_{0.95}$${\mathrm{Cr}}_{0.05}$${\mathrm{O}}_{2}$ based on powder data indicates that the probable space group is $F222$ and the room-temperature lattice parameters are ${a}_{o}=13.015$ \AA{}, ${b}_{o}=12.597$ \AA{}, and ${c}_{o}=5.795$ \AA{}. The stru…