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41.
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Ravinder Agarwal V. R. Singh M. M. Pradhan Ved Singh 《International Journal of Infrared and Millimeter Waves》1991,12(2):115-123
The occurance of the urinary stones varies according to the geographical regions. The presence of stones in the urinary system causes pain and discomfort. These generate colics and hence are sometimes life threatening. In the present study, infrared measurements have been made on several stone samples. It has been found that calcium oxalate, calcium phosphate, magnesiunm ammonium phosphate, calcium carbonate, uric acid, -cystine and xanthin are present, as expected. Also, silicon dioxide is found to be present in some of the stones but in small quantity, in addition to the above constituents. This constituent is responsible to exhibit piezoelectricity in the urinary calculi. 相似文献
43.
44.
Sushma Agarwal 《Journal of solution chemistry》1978,7(10):795-798
The excess volume of mixing of some electron-donating aromatic hydrocarbons like benzene, toluene,p-xylene, and mesitylene with an electronaccepting liquid 1,2,4-trichlorobenzene have been measured at 30°C. The results indicate that the interaction between the components increases as the electron-donating power of the hydrocarbons increases. The V
m
e
values are related to the ionization potentials of the hydrocarbons. 相似文献
45.
Biswanath Das Maddeboina Krishnaiah Keetha Laxminarayana K. Ravinder Reddy 《Journal of molecular catalysis. A, Chemical》2007,270(1-2):284-288
Sulfated zirconia has been employed as an efficient recyclable catalyst for the preparation of various β-acetamidoketones or esters at room temperature. The process involves the one-pot multicomponent reactions of aromatic aldehydes, enolizable ketones or β-ketoesters and acetonitrile in the presence of acetyl chloride. 相似文献
46.
In this paper we establish some new dynamic inequalities on time scales which contain in particular generalizations of integral and discrete inequalities due to Hardy, Littlewood, P′olya, D'Apuzzo, Sbordone and Popoli. We also apply these inequalities to prove a higher integrability theorem for decreasing functions on time scales. 相似文献
47.
By establishing a comparison result and using the monotone iterative technique combined with the method of upper and lower solutions, we investigate the existence of solutions for systems of nonlinear fractional differential equations. 相似文献
48.
Parallel rods / tubes flame support layers were used to study variations in geometry and materials on radiant burner performance. An increased density of rods increased the efficiency, as more surface area was provided to extract the heat of combustion. This effect was attenuated far fraction closed areas above 0·33 because of increased interference of direct base-to-load radiation. Thinner rods (with fraction closed area constant), having a lower thermal conduction resistance, fostered higher efficiency. Greater distances between the base and rods decreased efficiency due to air entrainment. This functioned to cool the base, increasing the range of combustion intensities where a portion of combustion lifted from the burner base. Isolation of radiating materials from conducting to the burner housing resulted in a ~ 5% upward shift in efficiency. Low to high efficiency was measured for alumina, mullite, and oxidized stainless steel rods, respectively; this was related directly to the emittances of the materials used. SiC and MoSi2 coatings on alumina rods resulted in burners which were as efficient as one with stainless steel rods. A burner designed as a restricted band spectral emitter was not as efficient in its high-emission range as a more graybody emitter under the same combustion intensity; the higher-temperature spectral emitter discouraged extraction of sensible heat from the combustion product stream. 相似文献
49.
Structural Chemistry - This work reports hydrogen uptake capacity and equilibrium isotope effect (EIE) for the Be, Li, and Ti-doped closoborate (B6H6) complexes using first-principles calculations... 相似文献
50.