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31.
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   
32.
本文就计算机在物理实验方面的辅助教学进行了较为深刻的研究和探索,并提出可行性的方案。  相似文献   
33.
The angular distributions of the (p, d), (d, t) and(3He, ) reactions on13C have been analysed within the framework of DWBA in which additional information on nuclear vertex constants was introduced. Although all these reactions seem to be similar single nucleon transfer, their mechanism is shown to be quite different and so is the information extracted thereof. While from the (p, d) reactions spectroscopic factors may be extracted unambiguously, from the (d, t) reactions it is possible to obtain directly the values of vertex constants only, which in turn are consistent with those determined by extrapolation of the experimental cross sections of the (p, d) reactions to the pole.In the case of (3He, ) reactions, however, the analysis indicates inadequacy of the DWBA concerning the calculations of central partial amplitudes. For a more reliable extraction of structural information, besides the correct normalization of peripheral amplitudes, a contribution of more complex mechanisms must be taken into account.  相似文献   
34.
In this paper, a natural R + n+1 extension of singular integrals, i.e.,T κ:fK t *t with K a standard C-Z kernel and ϕ usual one, is investigated. One of the main results is: Let (dμ, udx) ∈C1 and u-Mw, w∈A, then Tk is of type (Lp(udx), Lp(dμ)). As a related topic, a maximal operator is proved to be of type , where , provided (dμ, udx) ∈C1 and u∈ A. Supported by National Science Foundation of China  相似文献   
35.
The differential cross sections of tritons from the (d, t) reaction on9Be,10B and13C targets have been measured in the angular range of 5° LAB110° with relatively small errors, 5%. The experimental data were analysed in terms of the standard DWBA using both zero-range and exact finite-range approaches.  相似文献   
36.
在强有机碱1,8-二氮杂双环[5,4,0]十一-7烯(简称DBU)存在下,MnCl2与邻二氰基苯在某些二元醇溶剂中可高效合成Mn(Ⅱ)Pc(Pc表示酞菁),同时研究了不同溶剂对合成产物的物种及产率的影响和不同氧化态锰的酞菁配合物在一些醇溶剂中的互变现象  相似文献   
37.
采用喷雾干燥-高温固相法制备纳米LiFePO4与LiFePO4/C正极材料,用X-射线衍射,扫描电镜等对合成材料进行了表征,并对以LiFePO4为正极的电池进行了电化学性能测试。结果表明:材料合成最佳煅烧温度为600 ℃;合成过程中由于碳对LiFePO4晶型的生长有一定的抑制作用,相对于纯LiFePO4材料,LiFePO4/C材料粒径更小;并且,在此最佳合成温度下合成的LiF  相似文献   
38.
A vacuum ultraviolet photoionization mass spectrometric study of acetone   总被引:1,自引:0,他引:1  
The photoionization and dissociative photoionization of acetone have been studied at the photon energy range of 8-20 eV. Photoionization efficiency spectra for ions CH3COCH3+, CH3+, C2H3+, C3H3+, C3H5+, CH(2-)CO+, CH3CO+, C3H4O+, and CH3COCH2+ have been measured. In addition, the energetics of the dissociative photoionization has been examined by ab initio Gaussian-3 (G3) calculations. The computational results are useful in establishing the dissociation channels near the ionization thresholds. With the help of G3 results, the dissociation channels for the formation of the fragment ions CH3CO+, CH2CO+, CH3+, C3H3+, and CH3COCH2+ have been established. The G3 results are in fair to excellent agreement with the experimental data.  相似文献   
39.
INTRODUCTIONAdsorption has been considered to be the best available technology for removing organics from water in the USSafe Drinking Water Act[1]. Due to many drawbacks of activated carbon[2-7], the most widely used adsorbent,hypercrosslinked polymeric adsorbents developed by Tsyurupa and Davankov[8] have been increasingly viewedas an alternative to activated carbon for selective removal of specific organic substances from contaminatedwater[9-12], and series of researches have been do…  相似文献   
40.
A series of aminoalkyl-substituted polyfluorene copolymers with benzothiadiazole (BTDZ) of different content were synthesized by Suzuki coupling reaction, and their quaternized ammonium polyelectrolyte derivatives were obtained through a postpolymerization treatment on the terminal amino groups. Copolymers are soluble in environmentally friendlier solvents, such as alcohols. It was found that the efficient energy transfer occurs by exciton trapping on the narrow band gap BTDZ site under UV illumination. Only 1% of BTDZ content is needed to completely quench a fluorene emission for both the neutral and the quaternized copolymers in the neat film. Absolute PL efficiencies of copolymer films were greatly enhanced as a result of the suppression of excimer formation. Light-emitting devices fabricated from these copolymers show high external quantum efficiencies over 3% and 1% for the neutral precursor and the quaternized copolymers, respectively, with high work function metals such as Al as a cathode. To the best of our knowledge, this is the first report on an electroluminescent polymer which bears the high EL efficiency, the electron-injection ability from high work function metals, and the solubility in environment-friendly solvents at the same time. These features make them a promising candidate for the next generation of light-emitting copolymers in PLED flat panel display application.  相似文献   
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