Materials Literature
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An update of the taxa assigned to the genus Mastogloia is given. An estimated 410 taxa have been described as at November 1988. A cross-reference database of the similarities existing between 164 recently described taxa and 83 well-known ones is also reported. This may facilitate the identification of troublesome spec…
Abstract Alkylammonium benzene-, pyridine-3-, p-toluene-, and p-ethylbenzenesulfonates were found to be smectogenic when the cation carries an octyl or longer alkyl group. The thermal stability of the mesophase usually reaches its maximum at the octadecylammonium salt. The temperature range of stable existence is in t…
Steady-state and transient photoconductivity measurements have been made at different temperatures and intensities on the amorphous and partially crystallised films of Se 75 Te 25 prepared by vacuum evaporation. Partial crystallisation is achieved by annealing the films at a particular temperature near the crystallisa…
This paper presents the results of a study that was undertaken to optimize the ratio of the components of a new multicomponent inhibitor blend composed of nitrite/molybdate/inorganic phosphate. The mechanistic aspects of inhibition of the blend were also studied. Weight-loss and polarization data indicated that the op…
XPS and AES was used to detect phosphorus on electropolished copper obtained using different hydroxyethylidenediphosphonic acid (HEDP) concentrations, different p H, and various solutions ( , HEDP, and ). Since no phosphorus was detected on the copper surface, the viscous liquid film that formed could be easily elimin…
A three-band model which consists of one σ→σ* and two major π→π* electronic transitions was developed to account for the birefringence dispersion of a uniaxial liquid crystal. By comparing theory with experimental results, the contribution of each band to the overall birefringence is evaluated. The effect of each band…
Abstract The full structure of a new crystalline form of bis(1,2-diphenyl-1,2-ethenedithiolato)nickel, β-Ni(dpedt)2, has been determined by single crystal X-ray diffraction at room temperature. The structure was refined by full matrix least-squares to a final Rw=0.038. Comparison of this triclinic (P\bar1) structure w…
Abstract The new mineral bernardite has been identified on one specimen from Allchar, Macedonia, Yugoslavia, together with orpiment and realgar. It forms black crystals, the size of which may exceed 1 mm. The streak is deep red; on an arbitrarily oriented section R (589nm) ranges from 23.8 to 24.7% in air, from 10.2 t…
Abstract Short-chain alkylammonium derivatives of montmorillonite (< 8 or 10 C atoms in the alkyl chain) adsorb alcohols in the micropores between the alkylammonium ions. The external surface area and the micropore volume are derived from comparison plots of ethanol and butanol adsorption isotherms. The micropore v…
The type material of the type species of Cyclotella, Cyclotella tecta Håkansson & Ross (syn. C. operculata auct., non (Ag.) Kütz.), has been investigated by light and electron microscopy and compared with the original material of C. distinguenda Hustedt and C. plitvicensis Hustedt, and also with other similar taxa. It…
An alternating electric field is applied to a planarly aligned nematic liquid crystal with a positive dielectric anisotropy sandwiched between two electrodes. This leads to a reorientation of the director when the critical threshold for the Fr\'eedericksz transition is exceeded. Triggered by this reorientation process…
SUMMARY Release of potassium from 15 surface samples of benchmark Alluvial, Red and Black soils of India to 0.01 M solutions of BaCl 2 , CaCl 2 , NH 4 Cl and NaCl was studied in soils either untreated or pretreated with 5 × 10 −3 M KCl. In the untreated soils, the efficacy of the extractants declined in the sequence:…
2,3-Bisphosphoglycerate-independent phosphoglycerate mutase (EC 5.4.2.1) was purified and characterized from maize. SDS electrophoresis showed only one band with a molecular mass of 64 kDa, similar to that determined for the native enzyme by gel-filtration chromatography. The kinetic constants were similar to those re…
A method is described for examining and measuring fiber cuticular scale patterns from optical micrographs, impressions, or SEMs. The captured images are initially manipulated using several image processing functions to clarify scale structure. Image analysis is then done using a chain-coding routine that allows a numb…
Pullets of three genetic stocks derived from commercial White Leghorn-type chickens differed in relative productivity when they were beak trimmed or not and kept in 6-hen cages in a well-lighted house. An important part of the apparent discrepancy in rankings among stocks was associated with differences in mortality f…
Dynamic mechanical and tensile stress-strain properties were measured for four sets of acrylic pressure sensitive adhesives, and were compared to industry standard “applications” peel and shear properties. Correlations were established showing that more than half of the range of performance shown by commercial PSA's i…
We have incorporated the flexoelectric terms in developing one-dimensional models of E.H.D. instabilities in nematics both under D.C. and A.C. excitations. It is shown that, using this model, we can account for the following experimental observations, which could not be adequately explained by earlier models: (i) The…
Abstract The thermal degradation of polybutadiene (PB) samples having different initial contents of cis ‐1,4‐, trans ‐1,4‐ and 1,2‐units were investigated at temperatures lower than 250°C, where cyclization, cross‐linking and cis ‐ trans isomerization occur without depolymerization. Changes of the cis ‐ trans content…
Abstract The structure of well ground cellulose I and cellulose II samples was studied by measuring the X‐ray scattering intensities and calculating the corresponding radial atomic density functions (RDFs). Experimentally obtained results have been compared with model calculations mainly varying the packing of nearest…
Abstract The catalytic power of Ca-nontronite, Ca-bentonite, and Ca-kaolinite in promoting the abiotic ring cleavage of pyrogallol (1,2,3-trihydroxybenzene) and the associated formation of humic polymers was studied in systems free of microbial activity. The presence of Ca-kaolinite and especially Ca-nontronite in the…