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51.
5-(2-苯基-1,2,3-三唑基)-3-芳基吡唑啉衍生物的合成及其荧光性能 总被引:8,自引:0,他引:8
以2-苯基-1, 2, 3-三唑基-4-甲醛为原料, 与苯乙酮[或取代苯乙酮(1a~1d)]发生羟醛缩合, 生成相应的查尔酮(2a~2d), 再与不同的肼反应, 合成了12种新的5位含2-苯基-1, 2, 3-三唑基的吡唑啉衍生物3a~3d, 4a~4d, 5a~5d. 化合物的结构经元素分析、 IR光谱和1 H NMR谱确认, 并测定了化合物的荧光光谱. 结果显示所合成的目标化合物有荧光, 是一类新型的荧光化合物. 相似文献
52.
Chen Hui Li Hua Yu Qiu Cai Hong Xu 《中国化学快报》2007,18(12):1436-1438
Bis-silicon-bridged stilbene derivatives were synthesized in a modified procedure that combined the preparation of bis[2- (silyl)phenyl]acetylene and its intramolecular reductive cyclization in one pot.The results indicated that the one pot approach produced target products in a comparable yield to that of the two-step method reported previously. 相似文献
53.
Gen-di Wang Xiao-hui Zhang Yu-ming Chu 《Journal of Mathematical Analysis and Applications》2006,321(2):589-594
In this paper the authors study a monotonicity of several functions involving ma(r) and μa(r). By using these results, the authors obtain some new bounds of the solutions of Ramanujan's generalized modular equations. 相似文献
54.
Batchelor M. T. Guan X.-W. Oelkers N. Ying Z.-J. 《Journal of statistical physics》2004,116(1-4):571-589
We investigate the quantum phase diagram of the exactly solved mixed spin-(1/2,1) ladder via the thermodynamic Bethe ansatz (TBA). In the absence of a magnetic field the model exhibits three quantum phases associated with su(2), su(4), and su(6) symmetries. In the presence of a strong magnetic field, there is a third and full saturation magnetization plateaux within the strong antiferromagnetic rung coupling regime. Gapless and gapped phases appear in turn as the magnetic field increases. For weak rung coupling, the fractional magnetization plateau vanishs and the model undergoes new quantum phase transitions. However, in the ferromagnetic coupling regime, the system does not have a third saturation magnetization plateau. The critical behaviour in the vicinity of the critical points is also derived systematically using the TBA. 相似文献
55.
The He-McKellar-Wilkens (HMW) effect in non-commutative (NC) space is studied. By solving the Dirac equations on NC space, we obtain topological HMW phase in NC space where the additional terms related to the space non-commutativity are given explicitly. 相似文献
56.
研究了Neuman-Sándor平均NS(a,b)关于调和平均H(a,b)、算术平均A(a,b)、二次平均Q(a,b)若干特殊组合的序关系,给出最佳参数α1,α2,α3,α14,β1,β2,β3,β4∈(0,1),使得下列双向不等式:$\sqrt{a_{1}Q^{2}(a,b)+(1-a_{1})A^{2}(a,b)}< NS(a,b)<\sqrt{\beta_{1}Q^{2}(a,b)+(1-\beta_{1})A^{2}(a,b),}\\ \sqrt{[a_{2}Q(a,b)+(1-a_{2})A(a,b)]A(a,b)}< NS(a,b)<\sqrt{[\beta_{2}Q(a,b)+(1-\beta_{2})A(a,b)]A(a,b),}\\ \sqrt{a_{e}Q^{2}(a,b)+(1-a_{3})H^{2}(a,b)}< NS(a,b)<\sqrt{\beta_{3}Q^{2}(a,b)+(1-\beta_{3})H^{2}(a,b),}\\ \sqrt{[a_{4}Q(a,b)+(1-a_{4})H(a,b)]A(a,b)}< NS(a,b)<\sqrt{[\beta_{4}Q(a,b)+(1-\beta_{4})H(a,b)]A(a,b),}$对所有不同的正实数a和b均成立。 相似文献
57.
TianZhengping 《高校应用数学学报(英文版)》2004,19(4):455-458
A set of n points in the plane determines a total Cn^2 distances (some of them may be the same). Let rn be the ratio of the maximum distance to the minimum distance, and Rn be the greatest lower bound for rn.By using the mathematical software Mathematica,the author gets the following results in this paper.R12≤2.99496…,R13≤cscπ/10. 相似文献
58.
The algebraic structure and Poisson's integral theory of mechanico-electrical
systems are studied. The Hamilton canonical equations and generalized Hamilton
canonical equations and their the contravariant algebraic forms for
mechanico-electrical systems are obtained. The Lie algebraic structure and the
Poisson's integral theory of Lagrange mechanico-electrical systems are derived. The
Lie algebraic structure admitted and Poisson's integral theory of the
Lagrange--Maxwell mechanico-electrical systems are presented. Two examples are
presented to illustrate these results. 相似文献
59.
Lie symmetry algebra of linear nonconservative dynamical systems is
studied in this paper. By using 1--1 mapping, the Lie point and Lie
contact symmetry algebras are obtained from two independent
solutions of the one-dimensional linear equations of motion. 相似文献
60.
Studies on Adsorption Behavior and Mechanism of Copper( Ⅱ ) onto Amino Methylene Phosphonic Acid Resin 总被引:2,自引:0,他引:2
XIONG Chun-hua ** WANG Yong-jiang SHI Lin-mei . College of Food Science Biotechnology Environmental Engineering Hangzhou University of Commerce Hangzhou P. R. China . Department of Chemistry Lishui Teachers College Lishui P. R. China 《高等学校化学研究》2003,19(3):366-369
IntroductionThe adsorption ability of the functional poly-mer used to enrich metal ions is strong and the op-eration of the functional polymer is convenient.The polymer having adsorbed metal ions can be re-covered by means of an acid or an alkaline solutionand the recovered polymeric material can bereused.The adsorption ability of the polymer withvarious functional groups is different for differentmetals.Because nucleophilic atoms such as oxy-gen,nitrogen,sulphur and phosphorous atoms cancoord… 相似文献