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71.
AL Saari H Hyvönen M Lahtinen M Ylisirniö P Turhanen E Kolehmainen S Peräniemi J Vepsäläinen 《Molecules (Basel, Switzerland)》2012,17(9):10928-10945
Aminobisphosphonates, e.g., alendronate and neridronate, are a well known class of molecules used as drugs for various bone diseases. Although these molecules have been available for decades, a detailed understanding of their most important physicochemical properties under comparable conditions is lacking. In this study, ten aminobisphosphonates, H2N(CH2)nC(OH)[P(O)(OH)2]2, in which n = 2-5, 7-11 and 15 have been synthesized. Their aqueous solubility as a function of temperature and pH, pKa-values, thermal stability, IR absorptions, and NMR spectral data for bothliquid (1H, 13C, 31P-NMR) and solid state (13C, 15N and 31P-CPMAS NMR) were determined. 相似文献
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75.
Basavaraju Srinivas Kannekanti Lalitha Police Anil Kumar Reddy Gajeelli Rajesh Valluri Durga Kumari Machiraju Subrahmanyam Bhudev Ranjan De 《Research on Chemical Intermediates》2011,37(8):1069-1086
Abstract
The liquid-phase selective dehydrogenation of cyclohexanol has been investigated using two classes of catalyst containing either Cu2O or CuO on TiO2 under solar light in deaerated conditions at room temperature using acetonitrile medium in a batch reactor. The effect on dehydrogenation of three conditions, cyclohexanol concentration, copper loading on TiO2, and amount of catalyst, were investigated. The maximum yield of cyclohexanone obtained was 40%. The catalysts were characterized by XRD, UV–DRS, TEM, SEM–EDAX, and XPS. It was found that 1% (w/w) Cu2O/TiO2 was 100% selective for photocatalytic dehydrogenation of cyclohexanol. 相似文献76.
Miscibility studies of chitosan (CHI)/poly(vinyl alcohol) (PVA) blend in buffer solution were carried out in several blend compositions (10/90, 20/80, … , 90/10). Viscosity, ultrasonic velocity, density and refractive were measured at 30, 40 and 50°C, respectively. Using viscosity data, the interaction parameters μ and thermodynamic parameter α were computed to determine the miscibility of the blend in solution. These values revealed that the blend is miscible when the chitosan content is more than 60% in the blend. The obtained results were further confirmed by the ultrasonic velocity, density and refractive index study. 相似文献
77.
Manu Vaishakh 《Optik》2011,122(21):1947-1949
In confocal microscopes employing image fiber bundle, a focused beam is scanned sequentially over each fibers to build up the image. The effect of neighboring fibers around the illumination fiber on the confocality achieved is studied using Gaussian theory. It is shown that with proper packing of the fibers in the image fiber bundle, multiple fibers can be illuminated simultaneously without affecting the confocality. This will reduce the scanning time considerably without affecting the image resolution. 相似文献
78.
Devulapalli Venu Gopal Basavaraju Srinivas Mangalampalli Venkata Phanikrishna Sharma Lipsa Panda Pullur Anil Kumar Machiraju Subrahmanyam Valluri Durga Kumari 《Reaction Kinetics and Catalysis Letters》2004,83(1):63-70
The vapor phase hydrogenation of acetophenone at atmospheric pressure is carried out for the synthesis of 1-phenylethanol
in a fixed bed reactor using Cu-Zn-Al-O (LTS-1) and LTS-2, Zn-Cr-Al-O (HTS-1) and Zn-Cu-Cr-Al-O (HTS-2) metal oxide catalysts.
Our studies clearly indicate that a catalyst of low temperature hydrogenation activity, when modified for its acidity with
magnesium oxide, shows maximum selectivity of 1-phenylethanol.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
79.
The redox reaction between the 12-tungstocobaltate(III) ion and carbohydrazide is first order with respect to both the oxidant and the substrate. The observed pseudo first-order rate constant, kobs, is retarded by increasing the concentrations of H+ and alkali metal ion (Li+, Na+ and K+). There is a linear correlation between the kobs and the concentrations of carbohydrazide and H+ ion, but the plots of kobs against the concentrations of the alkali metal ions is non-linear. However, the same data is applicable to the Davies equation for the effect of the ionic strength on the kobs. 相似文献
80.
A recently reported study [Phys. Rev.
A49, 3664 (1994)] of elastic scattering of 81 keVγ rays in the angular range from 60° to 133° has been extended to smaller and larger angles. Previously reportedS matrix calculations of atomic Rayleigh scattering have been shown to require a subtraction of contributions from spurious
resonances. Most of the experimental data are in agreement with the calculations. Calculations (MF + ASF) based on a combination
of relativistic modified form factors (MF’s) and angle independent anomalous scattering factors (ASF’s) are found to be inadequate
for an explanation of experimental cross-sections in the case of highZ elements at angles larger than about 120°. 相似文献