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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
将Phelps引理, Ekeland变分原理, Pareto有效性定理推广到拓扑线性空间,同时证明了这三个定理与郑喜印证明的拓扑线性空间中的Drop定理彼此等价. 相似文献
992.
993.
The “true detection limit” CL,true was measured by a method proposed by Boumans et al. for 10 prominent lines of La, Ce, Pr, Nd and Sm, the most abundant rare
earth elements (REEs) in geological samples. It is demonstrated how spectral interferences can increase of CL,true. The spectra were excited in an argon arc plasma jet with evaporation powders of five complex natural samples. The data show
that there is a significant increase of CL,true in real samples containing large concentrations of such elements as Ti, Zr, Cr, Nb, Ta and REEs emitting complex spectra.
Received: 17 June 1997 / Revised: 20 October 1997 / Accepted: 26 October 1997 相似文献
994.
M. G. Bettoli M. Ravanelli L. Tositti O. Tubertini L. Guzzi W. Martinotti G. Queirazza M. Tamba 《Radiation Physics and Chemistry》1998,52(1-6):327-331
Decomposition by ionizing radiations of p-chlorophenol and tetrachloroethylene in synthetic water samples at about 2 mg Cl L−1, has been studied on laboratory-scale experiments. Bicarbonate/carbonate and nitrate ions, at two concentration levels (20 and 200 mg HCO3−1 and 1 and 50 mg NO3−L−) were added to synthetic samples in order to evaluate their influence on decomposition yield. At 5 kGy γ dose level, a quantitative degradation of p-chlorophenol is obtained whereas only qualitative consideration can be drawn on tetracholoroethylene. Comparative study with respect to degradation of p-cholophenol solutions (about 2 mg Cl L−1) by γ-rays and electron beam irradiation treatment at 0.5 kGy dose level, are in progress; preliminary results indicate that irradiation with γ-rays seems to be more efficient in terms of removal efficiency respect to electron beams source. 相似文献
995.
996.
Semilinear Differential Inclusions in Separable Banach SpacesXueXingmei(薛星美)andSongGuozhu(宋国柱)(DepartmentofMathematics,Nanjin... 相似文献
997.
V. V. Rumyantsev S. P. Sosnitskii 《Journal of Applied Mathematics and Mechanics》1993,57(6):1101-1122
The problem of the stability of the equilibrium positions and steady motions of holonomic conservative systems has been fairly completely treated in a number of reviews [44,58,9]. However, investigations are continuing in this field and a number of new important results have recently been obtained (in 1982–1992). This review analyses these results and compares them with previous ones. 相似文献
998.
Anupama Chaurasia Krishna K. Verma 《Fresenius' Journal of Analytical Chemistry》1995,351(2-3):335-337
2,4-Dinitrophenylhydrazine has been suggested as a new reagent for the flow-injection spectrophotometric determination of residual chlorine based on its oxidation to 2,4-dinitrophenyldiazonium ion. The measurement of the decrease in colour intensity under reversed flow-injection (reagent injection) conditions has been used for the determination of 0.1–10 mg/l Cl present as free or combined chlorine, and for its speciation. The limit of detection was 0.05 mg/l Cl. Copper (II), iron (III) and many other ions have been found not to vitiate the results. 相似文献
999.
1000.
Richard A. Cairncross Jeffrey G. Becker Shri Ramaswamy Ryan O'Connor 《Applied biochemistry and biotechnology》1996,131(1-3):774-785
Management of moisture penetration and hydrolytic degradation of polylactide (PLA) is extremely important during the manufacturing,
shipping, storage, and end-use of PLA products. Moisture transport, crystallization, and degradation, in PLA have been measured
through a variety of experimental techniques including size-exclusion chromatography, differential scanning calorimetry, and
X-ray diffraction. Quartz crystal microbalance and dynamic vapor sorption experiments have also been used to measure moisture
sorption isotherms in PLA films with varying crystallinity. A surprising result is that, within the accuracy of the experiments,
crystalline and amorphous PLA films exhibit identical sorption isotherms. 相似文献