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在25±0.1℃、I=0.1 mol·L-1 KNO3条件下,应用pH法测定了氨基酸水杨醛席夫碱(Sal∶A,A配体)-α-氨基酸(Aa,B配体)三元配合物的稳定常数,实验发现在三元配合物的稳定性与B配体的碱性之间存在良好的线性自由能关系。同时,以稳定性数据为探针,研究了三元配合物分子内存在的配体间疏水缔合作用。  相似文献   
3.
氨基酸水杨醛席夫碱与铜(Ⅱ)配合物的合成及其抗菌活性和稳定性、结构间的关系毕思玮*刘树祥(曲阜师范大学化学系,曲阜273165)关键词:氨基酸水杨醛席夫碱铜(Ⅱ)稳定常数抗菌活性实验部分将10mmol氨基酸和0.56g(10mmol)KOH溶于热的9...  相似文献   
4.
Water swelling rubber (WSR) was prepared by reaction blending SBR andsodium polyacrylate (PAANa). The existing states of water in the WSR was studied bymeans of DSC and TG. It was found that water exists in three states: nonfreezing water,bound freezable water and free water. The relationships between water states and structureof PAANa were investigated. The results showed that the amount of non-freezing waterwas related to total water content, and the ratio of non-freezing water versus -COONagroups on PAANa (mol/mol) was about 4. However, total water content slightly affectedthe content of bound freezable water and remarkably affected the amount of free waer.  相似文献   
5.
n-Salicylideneamino acids and their Cu(Ⅱ) complexes are synthesized. The structures of the compounds are characterized by elementary analysis, molar conductance, magnetic susceptibility, electronic and infrared spectra. The stability constants and the antibacterial activities have been determined. The relativity between antibacterial activities and structures of ligands and stability of complexes has been preliminarily studied.  相似文献   
6.
In this paper we formulate a continuous-time mean–variance portfolio selection model with multiple risky assets and one liability in an incomplete market. The risky assets’ prices are governed by geometric Brownian motions while the liability evolves according to a Brownian motion with drift. The correlations between the risky assets and the liability are considered. The objective is to maximize the expected terminal wealth while minimizing the variance of the terminal wealth. We derive explicitly the optimal dynamic strategy and the mean–variance efficient frontier in closed forms by using the general stochastic linear-quadratic (LQ) control technique. Several special cases are discussed and a numerical example is also given.  相似文献   
7.
In this paper, we introduce the notion of f-harmonic map with potential H with respect to the functional E f,H . We use the stress-energy tensor to obtain some monotonicity formulas and Liouville type theorems for f-harmonic maps with potential H under some conditions on f and H.  相似文献   
8.
A series of novel N-arylpyrazole derivatives (4a–4l) bearing the sulfonamide moiety were synthesized by the condensation reaction of 1,3-dicarbonyl compounds with 4-hydrazinylbenzenesulfonamide. The structures of the obtained compounds were established on the basis of elemental (C, H, and N) and spectral analysis (1H NMR, 13C NMR, ESIMS, and FT-IR). These compounds were tested for their in vitro cytotoxic activity against three human tumor cell lines: MCF-7, Hela, and A549. The results showed that most of the obtained compounds exhibited promising cytotoxicity against the tested cell lines with low IC50 values. The pyrazole derivative 4k, bearing two methoxy groups on the 3-position and 4-position of the phenyl ring, was the most effective one. Its inhibition of cell growth of MCF-7 cells was better than that of celecoxib and cisplatin.  相似文献   
9.
In this paper, we propose a new prototype model of a micro pump using ICPF (Ionic Conducting Polymer Film) actuator as the servo actuator. This micro pump consists of two active oneway valves that make use of the same ICPF actuator. The overall size of this micro pump prototype is 12mm in diameter and 20 mm in length. The actuating mechanism is as follows: (1) The ICPF actuator as the diaphragm is bent into anode side by application of electricity. Then the volume of the pump chamber increases, resulting in the inflow of liquid from the inlet to the chamber. (2) By changing the current direction, the volume of the pump chamber decreases, resulting in the liquid flow from the chamber to the outlet. (3) The ICPF actuator is put on a sine voltage, the micro pump provides liquid flow from the inlet to the outlet continuously. Characteristic of the micro pump is measured. The experimental results indicate that the micro pump has the satisfactory responses.  相似文献   
10.
In this paper,using the notion of an isolating block and Conley's attractor theory,an existence criterion of trajectories connecting a pair of invariant sets of ordinary differential equations is given.  相似文献   
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