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排序方式: 共有666条查询结果,搜索用时 15 毫秒
71.
72.
Arvind Kumar Jain Harsh Mohan Sunita Sharma 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2010,268(11-12):1790-1792
The collision progression including ionization of an inner-shell by an energetic proton and decay of vacancy is a motivating theme in ion-beam analysis. To explore measured vacancy de-excitation parameters for Pb, intensity ratios are experimentally determined from L X-rays with proton impact in the energy range 225–400 keV. Predictions of UAECPSSR theory are employed for ionization cross-sections. For atomic parameters such as transition rates, fluorescence, Auger and Coster–Kronig (CK) yields, various databases are used. In this paper, significance of these features and current progress are discussed. 相似文献
73.
Arvind Bharti 《Bulletin of Materials Science》1988,11(2-3):191-212
A brief state-of-the-art review of laser welding has been presented. Results of our experimental studies on laser welding
of Ti-6Al-4V have been reported. Results of weld evaluation including microstructure, mechanical properties and microchemistry
have also been presented. 相似文献
74.
75.
R. Heidinger J. Knaster H. Matsumoto M. Sugimoto A. Mosnier F. Arbeiter N. Baluc P. Cara S. Chel A. Facco P. Favuzza V. Heinzel A. Ibarra V. Massaut G. Micciche F.S. Nitti J. Theile 《Fusion Engineering and Design》2013,88(6-8):631-634
The International Fusion Materials Irradiation Facility (IFMIF) Engineering Design and Engineering Validation Activities (EVEDA) are being developed in a joint project in the framework of the Broader Approach (BA) Agreement between EU and Japan. This project has now entered into a crucial phase as the engineering design of IFMIF is now being formulated in a series of 3 subsequent phases for delivering an Interim IFMIF Engineering Design Report (IIEDR) by mid of 2013. Content of these phases is explained, including the plant configuration detailing the 5 IFMIF facilities and their systems. Together with the Engineering Design Activities, prototyping sub-projects are pursued in the Engineering Validation Activities which consist of the design, manufacturing and testing of the following prototypical systems: Linear IFMIF Prototype Accelerator (LIPAc), EVEDA Lithium Test Loop (ELTL), and High Flux Test Module (HFTM) with the prototypical helium cooling loop (HELOKA). Highlights are described from recent experiments in the Engineering Validation Activities. 相似文献
76.
77.
A stability indicating assay method based on highperformance liquid chromatography has been developed for the quantitation of hydrochlorothiazide in combination with methyldopa and propranolol hydrochloride. The method is accurate, reproducible and precise with an average percent relative standard deviation of 1.3. The method can also be used for the quantitation of the only known impurity/decomposition product (4-amino, 6 chloro, 1,3 benzenedisulfonamide) in hydrochlorothiazide. For the complete separation of methyldopa from hydrochlorothiazide, a counterion, 1-heptanesulfonic acid sodium was added to the mobile phase to increase the retention time of methyldopa. A 4-5 minutes time to extract hydrochlorothiazide from tablets appears to be satisfactory. 相似文献
78.
The recently developed mathematical technique for studying the parametric sensitivity of reactors is extended to include chain polymerization systems exhibiting the gel and glass effects, as well as physical property variations. The sensitivities of the two temperature maxima with respect to various parameters are computed. It is found that, for a sample system, poly(methyl methacrylate), all the sensitivities of the gel effect induced temperature peak attain their maxima at the same conditions—this leads to a generalized temperature sensitivity constraint applicable to reactor design or operation. This sensitivity boundary is associated with high conversions and high molecular weights. The analysis shows that the dimensionless propagation activation energy, ?p, and the dimensionless initiation activation energy, ?d, are the two most important parameters governing the system performance. Sensitivities of the gel effect-induced number average chain length peak with respect to various parameters are also obtained. Again, all of these chain length sensitivities show maxima at the same condition, leading to the concept of a generalized chain length sensitivity criterion of constraint. Most importantly, the temperature and chain length sensitivity boundaries are virtually identical. 相似文献
79.
80.
Arvind Narurkar Pai-Chang Sheen Ernest L. Hurwitz Matthew A. Augustine 《Drug development and industrial pharmacy》1987,13(2):319-328
The particle size reduction of chlorthalidone by fluid energy milling, Alpine milling and Fitzpatrick milling were evaluated. The desired particle size was achieved by both the fluid energy milling and Alpine milling processes. Alpine mil1ing, however, is a more complex process and is susceptible to product decomposition, whereas fluid energy milling is a simple and efficient process without any risk of product decomposition. The desired particle size cannot be achieved by Fitzmilling because of the low probability of impaction force on particles. The dissolution rate of the chlorthalidone from chlorthalidone/propranolol hydrochloride tablets (25/80 mg) prepared with fluid energy milled chlorthalidone was significantly better than the tablets prepared with Fitzpatrick - milled chlorthalidone. The minimum effective specific surface area of chlorthalidone needed for maximum dissolution in water was found to be around 3.5 m2/g. 相似文献