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91.
92.
程立新 《应用泛函分析学报》2011,13(4):349-350,391
从泛函分析观点来看Lebesgue积分,使得Lebesgue积分可以用泛函分析最简单最基本的方法独立导出.基本做法是将Riemann对于区间[0,1]上的连续函数的积分看成连续函数空间C[0,1]上的连续线性泛函,再将它“自然”延拓到C[0,1]在积分范数意义下的完备化空间,而这个完备化空间正是Lebesgue可积函数空间L1[0,1]. 相似文献
93.
In this paper, we show that every infinite dimensional Banach space admits a homogenous measure of non-compactness not equivalent to the Hausdorff measure. Therefore, it resolves a long-standing question. 相似文献
94.
ABSTRACTIn this paper, synthesis of titanium silicon carbide (Ti3SiC2) under high pressure and high-temperature condition has been investigated by using the reactant systems Ti/Si/C, Ti/SiC/TiC, Ti/SiC/C and Ti/TiC/Si. Results reveal that Ti/TiC/Si is unsuited to the synthesis of Ti3SiC2 under a high pressure of 2.0?GPa, while an elemental mixture of Ti/Si/C is applicable. By the addition of Al, Ti3SiC2 with 95.8?wt% purity was obtained from elemental mixture with a large excess of silicon. The optimum experimental parameters were determined as Ti/Si/Al/C having the molar ratio of 3:1.5:0.5:1.9, holding at 2.0?GPa and 1300?°C for 60?min. 相似文献
95.
First we study several extremal problems on minimax, and prove that they are equivalent. Then we connect this result with the exact values of some approximation characteristics of diagonal operators in different settings, such as the best n-term approximation, the linear average and stochastic n-widths, and the Kolmogorov and linear n-widths. Most of these exact values were known before, but in terms of equivalence of these extremal problems, we present a unified approach to give them a direct proof. 相似文献
96.
Gustavo A. Narvaez Lixin He Gabriel Bester Alex Zunger 《Physica E: Low-dimensional Systems and Nanostructures》2006,32(1-2):93
We show how an atomistic pseudopotential plus many-body configuration interaction theory can address the main spectroscopic features of self-assembled dots including, excitons, trions, biexcitons, fine-structure, charging spectra as well as electric-field dependence of entanglement in dot molecules. 相似文献
97.
98.
Lixin Xing 《Tetrahedron》2007,63(38):9382-9386
Pd-C catalyzed hydrogenolysis of benzaldehydes to methylbenzenes has been described to proceed via a ‘benzenemethanol pathway’. In this article, a novel ‘acetal pathway’ was first revealed by a systematic study when lower alcohols were used as solvents and a solvent-controlled highly efficient procedure was established. 相似文献
99.
本文用正电子湮没技术对等离子体喷涂铜基合金压缩形变的微观缺陷进行了测量。对等离子体喷涂合金,随着压缩量的增加,正电子寿命变短,这一现象与常规合金中观察到的情况相反。 相似文献
100.
Zhaohui Tang Xuesi Chen Qizhi Liang Xinchao Bian Lixin Yang Longhai Piao Xiabin Jing 《Journal of polymer science. Part A, Polymer chemistry》2003,41(13):1934-1941
An amino isopropoxyl strontium (Sr‐PO) initiator, which was prepared by the reaction of propylene oxide with liquid strontium ammoniate solution, was used to carry out the ring‐opening polymerization (ROP) of cyclic esters to obtain aliphatic polyesters, such as poly(ε‐caprolactone) (PCL) and poly(L ‐lactide) (PLLA). The Sr‐PO initiator demonstrated an effective initiating activity for the ROP of ε‐caprolactone (ε‐CL) and L‐lactide (LLA) under mild conditions and adjusted the molecular weight by the ratio of monomer to Sr‐PO initiator. Block copolymer PCL‐b‐PLLA was prepared by sequential polymerization of ε‐CL and LLA, which was demonstrated by 1H NMR, 13C NMR, and gel permeation chromatography. The chemical structure of Sr‐PO initiator was confirmed by elemental analysis of Sr and N, 1H NMR analysis of the end groups in ε‐CL oligomer, and Fourier transform infrared (FTIR) spectroscopy. The end groups of PCL were hydroxyl and isopropoxycarbonyl, and FTIR spectroscopy showed the coordination between Sr‐PO initiator and model monomer γ‐butyrolactone. These experimental facts indicated that the ROP of cyclic esters followed a coordination‐insertion mechanism, and cyclic esters exclusively inserted into the Sr–O bond. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 1934–1941, 2003 相似文献