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1.
以甲基丙烯酸甲酯(MMA)和三氯甲烷(CHCl3)为油相制备反胶束微乳液, 依靠表面活性剂十六烷基三甲基溴化铵(CTAB)自组装形成的“微反应器”作为模板成功地制备了PMMA/Eu(OH)3/EG和PMMA/Ni(OH)2/EG纳米复合材料. 并用红外光谱(IR)、扫描电镜(SEM)、透射电镜(TEM)、X射线衍射(XRD)和差热-热重(TG-DTA)对该复合材料进行了表征和分析. 研究结果表明, 反胶束法可以有效地应用于有机-无机纳米复合材料的制备.  相似文献   
2.
含八齿苦味酸根的超分子苦味酸钾的合成和结构   总被引:1,自引:0,他引:1  
A supramolecular complex, [Kpic]n (pic- is picratol, (NO2)3C6H2O-), has been synthesized unexpectedly in acetone solution, and characterized by elemental analysis, IR and X-ray crystallography. In the complex, the K+∶pic- is 1∶1, and one K(Ⅰ) ion is surrounded by six picrate anions, one picrate anion can coordinate to six K(Ⅰ) ions. The coordination number of every potassium atom is eight. Interestingly, the picratol adopts an eight-coordinated ideal mode unreported. CCDC: 630627.  相似文献   
3.
Two new mono- and dinuclear Cu(II) complexes, namely [CuL1]·0.5H2O (1) and [(Cu2(L2)2)(DMF)]·0.5DMF (2) (H2L1 = 1,2-bis{[(Z)-(3-methyl-5-oxo-1-phenyl-1H-pyrazolidin-4(4H)-yl)(phenyl)]methylene-aminooxy}ethane; H2L2 = 1,3-bis{[(Z)-(3-methyl-5-oxo-1-phenyl-1H-pyrazolidin-4(4H)-yl)(phenyl)] methyleneaminooxy}propane), have been synthesized and characterized by X-ray crystallography. The unit cell of complex 1 contains two crystallographically independent but chemically identical [CuL1] molecules and one crystalline water molecule, showing a slightly distorted square-planar coordination geometry and forming a wave-like pattern running along the a-axis via hydrogen bonding and π···π stacking interactions. Complex 2 has a dinuclear structure, comprising two Cu(II) atoms, two completely deprotonated phenolate bisoxime (L2)2− moieties (in the form of enol), and both coordinated and hemi-crystalline DMF molecules. Complex 2 has square-planar and square-pyramidal geometries around the two copper centers, whose basic coordination planes are almost perpendicular and form an infinite three-dimensional supramolecular network structure involving intermolecular C–H···N, C–H···O, and C–H···π(Ph) hydrogen bonding and π···π stacking interactions of neighboring pyrazole rings.  相似文献   
4.
The transport of the overdamped Brownian particles in a spatially periodic potential subject to the three value Poissonian noise in the stationary state is considered. We show that for the spatially periodic potential, no matter whether it is asymmetric, or is symmetric, flux can be induced. But the mechanism is different. The former is the common action of broken reflection symmetry and transition among three-value Poissonian noise in a cyclic way; the latter is single behavior of transition among three-value Poissonian noise in a cyclic way.  相似文献   
5.
In this paper, we consider three kinds of temporal-spatial dichotomous noises. Three systems driven by these noises are studied, respectively. The master equations for these systems are derived.  相似文献   
6.
The phenomenon of stochastic resonance (SR) in a bistable nonlinear system is studied when the system is driven by the asymmetric potential and additive Gaussian colored noise. Using the unified colored noise approximation method, the additive Gaussian colored noise can be simplified to additive Gaussian white noise. The signal-to-noise ratio (SNR) is calculated according to the generalized two-state theory (shown in [H.S. Wio and S. Bouzat, Brazilian J.Phys. 29 (1999) 136]). We find that the SNR increases with the proximity of a to zero. In addition, the correlation time τ between the additive Gaussian colored noise is also an ingredient to improve SR. The shorter the correlation time τ between the Gaussian additive colored noise is, the higher of the peak value of SNR.  相似文献   
7.
In this paper, we obtain a 1+1 dimensional integrable differential-difference model for the sine-Gordon equation by Hirota's discretization method. A bilinear Backlund transformation and the associated Lax pair are also proposed/or this model.  相似文献   
8.
Ni-Al bimetallic catalysis proves to be an efficient catalytic strategy for unreactive bond transformations. Recently, chiral bifunctional ligands, especially amphoteric secondary phosphine oxide(SPO) ligand, are used for a more powerful synergistic effect in the bimetal-catalyzed reactions, providing not only milder reaction conditions and higher reactivity but also excellent reaction selectivity. Herein, we give a brief review on the development of Ni-Al bimetallic catalytic system and highlight recent advances in enantioselective Ni-Al bimetallic catalysis for unreactive bond transformation.  相似文献   
9.
Two CoII complexes, namely {[CoL(MeOH)(μ-OAc)]2Co}·2MeCN·2MeOH (1) and {[CoL(EtOH)(μ-OAc)]2Co}·3EtOH (2) (H2L=3,3′-dimethoxy-2,2′-[(1,3-propylene)dioxybis(nitrilomethylidyne)]diphenol), have been synthesized and characterized by X-ray crystallography. Both complexes contain octahedral coordination geometries, comprising three CoII atoms, two deprotonated bisoxime L2− units in which four μ-phenoxo oxygen atoms form two [CoL(X)] (X = MeOH or EtOH) units, two acetate ligands coordinated to three CoII centers through Co–O–C–O–Co bridges, and coordinated and non-coordinated solvent. Both complexes exhibit 2D supramolecular networks through different intermolecular hydrogen-bonding interactions.  相似文献   
10.
In this paper, we prove that the global existence of classical solutions to the Cauchy problem for the minimal surface equation with slow decay initial value in Minkowskian space time.  相似文献   
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