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1.
M K Parida Nita Sinha B Adhikary B Allanach A Alok K S Babu B Brahmachari D Choudhury E J Chun P K Das A Ghosal D Hitlin W S Hou S Kumar H N Li E Ma S K Majee G Majumdar B Mishra G Mohanty S Nandi H Pas M K Parida S D Rindani J P Saha N Sahu Y Sakai S Sen C Sharma C D Sharma S Shalgar N N Singh S Uma Sankar N Sinha R Sinha F Simonetto R Srikanth R Vaidya 《Pramana》2006,67(5):849-860
This is the report of flavor physics and model building working group at WHEPP-9. While activites in flavor physics have been
mainly focused on B-physics, those in model building have been primarily devoted to neutrino physics. We present summary of working group discussions
carried out during the workshop in the above fields, and also briefly review the progress made in some projects subsequently. 相似文献
2.
Kamat R. V. Sawant R. M. Mhatre H. R. Chaudhuri N. K. Vaidya V. N. 《Journal of Radioanalytical and Nuclear Chemistry》1998,238(1-2):33-41
pH titration curves generated by slow addition of alkali to solutions containing varying concentrations of uranyl nitrate
and nitric acid were studied using an autotitrator linked to a personal computer. A procedure with multiple choice of equations
has been developed for the estimation of free acid, nitrate and uranium in pure uranyl nitrate solution by a single titration.
The technique provides a simple single-step method with required accuracy and precision for the simultaneous estimation of
the three quantities in the uranyl nitrate feed solution of the sol-gel process for making UO3 microspheres. The relative standard deviations in the determination of uranium and nitrate were ±0.82% and ±1.52%, respectively,
in 15 determinations. 相似文献
3.
P. C. Vaidya 《General Relativity and Gravitation》1978,9(9):801-807
The metric for the standard static Einstein model of the universe can be expressed in coordinates for which a congruence of spacelike world lines of the model will be twisting. A method of shifting the twist has been devised by which the twist on spacelike world lines is shifted onto the timelike world lines. The model universe then becomes Gödel's model. A combined Einstein-Gödel model containing a parameter is obtained. Switching from +1 to –1 will effect the shift of twist in the world lines and lead from the Einstein model to the Gödel model. 相似文献
4.
A DTA apparatus has been built to examine some of the errors neglected in present quantitative DTA. The heat transfer characteristics within DTA systems were found to limit in situ measurements of powder thermal conductivity. It was also demonstrated that the negligence of heat lost to the DTA block from the sample cell during an exothermic reaction and heat gained from the DTA block by the sample cell during endothermic reactions lead to large errors in quantitative estimations. A modified double differential thermocouple DTA was designed to take these heat losses into account. The apparatus was calibrated with CaCO3 and kaolinite endotherms and the kaolinite exotherm and tested on the SrCO3 rhombic trigonal inversion endotherm. The result was found to be in good agreement with accepted literature values.
Zusammenfassung Ein DTA-Apparatur wurde gebaut um einige in der gegenwärtig üblichen quantitativen DTA vernachlässigte Fehler zu prüfen. Es wurde gefunden, daß die Wärmeübertragungscharakteristika in DTA-Systemen die in situ Messungen der Wärmeleitfähigkeit von Pulvern begrenzen. Es wurde ebenfalls gezeigt, daß die Vernachlässigung von Wärmeverlusten der Probezelle an den DTA-Block bei exothermen Reaktionen und vom Wärmegewinn der Probezelle vom DTA-Block bei endothermen Reaktionen zu bedeutenden Fehlern in den quantitativen Bestimmungen führt. Ein DTA-Gerät mit doppeltem Differentialthermoelement wurde entworfen um diese Wärmeverluste zu berücksichtigen. Der Apparat wurde mittels der endothermen Reaktionen von CaCO3 und Kaolinit, bzw. mittels der exothermen Reaktion von Kaolinit geeicht und an der Inversion von rhombischem zu trigonalem SrCO3 erprobt.
Résumé On a réalisé un appareil ATD pour étudier certaines erreurs négligées jusqu'à présent en ATD quantitative. On a trouvé ainsi que les caractéristiques du transfert de chaleur limitent la mesure in situ de la conductivité thermique des poudres. On montre également que le fait de négliger les échanges de chaleur entre la cellule renfermant l'échantillon et le bloc ATD (pertes ou gains de chaleur suivant que les réactions sont exothermiques ou endothermiques) conduit à des erreurs considérables dans les dosages. Un double thermocouple différentiel a été conçu pour tenir compte de ces pertes. L'étalonnage de l'appareil a été ré alisé à l'aide des réactions endothermiques de CaCO3 et de la kaolinite et contrôlé avec la transition endothermique de SrCO3 (rhomboédrique-trigonal).
DTA , DTA. , DTA . , , DTA DTA . , . CaCO3 SrCO3.相似文献
5.
Highlights? Recycling of genetic material is important for the origins of life ? Simulation studies show recycling leads to the selection of genotypes from a pool ? Recycling can lead to the sudden emergence of a high-fitness RNA genotype ? Experimental studies with the Azoarcus ribozyme show fragment recycling 相似文献
6.
7.
Menon S Vaidya H Pillai S Vidya R Mitscher LA 《Combinatorial chemistry & high throughput screening》2003,6(5):471-480
A solution phase strategy for the multiple parallel synthesis of a demonstration library of indazoles is described by which regio-selectivity problems inherent to previous syntheses of this nucleus are largely overcome. Synthesis of selected components proceeded satisfactorily indicating that a fully realized library of indazole analogs could readily be produced using this methodology. Simple modifications of the basic nucleophilic aromatic substitution route unambiguously produce a range of N-1 substitutions (alkyl, aryl and aralkyl) in 50-75% yields. Next a range of substituents was introduced at the C-3 position in 50-80% yields by O-alkylation. Careful choice of reagents and reaction conditions were required to prevent by-product formation due to competing alkylation at N-2 (trace to 15% yields). When present, these contaminants were readily removed by chromofiltration. A third diversity site was sketched in at C-5 in 75-90% yield by reductive alkylation or acylation. Screening of some of the demonstration library members in vitro revealed highly active antioxidants suggesting that producing a full library would be worthwhile. 相似文献
8.
Nayan Patel Mehmet Krta Vaidya Sankaran Suresh Menon 《Proceedings of the Combustion Institute》2007,31(2):2327-2334
Large-eddy simulation (LES) of a liquid-fueled lean-direct injection (LDI) combustor is carried out by resolving the entire inlet flow path through the swirl vanes and the combustor. A localized dynamic subgrid closure is combined with a subgrid mixing and combustion model so that no adjustable parameters are required for both non-reacting and reacting LES. Time-averaged velocity predictions compare well with the measured data. The unsteady flow features that play a major role in spray dispersion, fuel–air mixing and flame stabilization are identified from the simulation data. It is shown that the vortex breakdown bubble (VBB) is smaller with more intense reverse flow when there is heat release. The swirling shear layer plays a major role in spray dispersion and the VBB provides an efficient flameholding mechanism to stabilize the flame. 相似文献
9.
Gundibasappa K. Nagaraja Vijayavittala P. Vaidya Koodamara Sheshappa Rai Kittappa M. Mahadevan 《Phosphorus, sulfur, and silicon and the related elements》2013,188(12):2797-2806
A novel and efficient method for the synthesis of substituted thiazepines and diazepines has been developed. A simple one-pot reaction of chalcones 1a–f with 1-amino-2-mercapto-5-phenyl-1,3,4-triazole and o-phenylenediamine in the presence of a catalytic amount of sodium acetate under microwave irradiation gave 2-(3,8-diphenyl-7,8-dihydro[1,2,4]triazolo[3,4-b][1,3,4]thiadiazepin-6-yl)phenoles 2a–f and 2-(2-phenyl-2,3-dihydro-1H-1,5-benzodiazepin-4-yl)phenoles 3a–f, respectively. The structure of all the synthesized compounds was elucidated on the basis of elemental analysis, IR, 1H and 13C NMR, and mass spectral data. 相似文献
10.
Vikas V. Vaidya Santosh M. Yetal Shikha M. N. Roy Noel A. Gomes Santosh S. Joshi 《Chromatographia》2007,66(11-12):925-928
A rapid, sensitive and specific method to quantify pregabalin in human plasma using metaxalone as the internal standard is described. Sample preparation involved simple protein precipitation by using acetronitrile as solvent. The extract was analyzed by high-performance liquid chromatography coupled to electrospray tandem mass spectrometry (LC-MS–MS). Chromatography was performed isocratically on Thermo Hypurity C18 5 μm analytical column, (50 mm × 4.6 mm i.d.). The assay of pegabalin was linear calibration curve over the range 10.000–10000.000 ng mL?1. The lower limit of quantification was 10.000 ng mL?1 in plasma. The method was successfully applied to the bioequivalence study of pregabalin capsules (150.0 mg) administered as a single oral dose. 相似文献