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101.
根据反应层的概念对在任一给定形状微电极上进行的准一级和二级均相催化反应机理(EC'')的稳态电化学行为进行了研究。本方法简便易行,不需要解复杂方程的数学技巧。利用推导出的这些方程,可计算准一级和二级均相催化反应的动力学常数。 相似文献
102.
One novel complex [Co(p-MBA)2(2,2'-bipy)(H2O)]·(H2O) has been synthesized by the reaction of p-methylbenzoic acid with 2,2'-bipyridine in the solvent mixture of water and methanol. It crystallizes in triclinic, space group P-1 with a=0.70479(14), b=1.1211(2), c=1.6718(3) nm, α=103.806(3), β=90.795(3), γ=104.207(3)°, V=1.2399(4) nm3, Mr=512.41, Dc=1.373 g/cm3, Z=2, F(000)=532, μ=0.733 mm-1, R=0.0432 and wR=0.0957. The crystal structural analysis shows that the cobalt atom is coordinated with three oxygen atoms from two p-methylbenzoic acids and one water molecule and two nitrogen atoms from one 2,2'-bipyridine,forming a distorted square-pyramidal coordination geometry. The cyclic voltammetry behavior of the complex is also reported. 相似文献
103.
合成了9种具L-氨基酸衍生物结构的介晶化合物(I-Ⅲ,Ⅳab,Ⅴa,b,Ⅵa,b)、4种氨基酸衍生物(A1-4)和6种介晶化合物(M1-6).新化合物(Ⅰ-Ⅲ,Ⅳa,b,Ⅴa,b,Ⅵa,b,A4,M3-6)的化学结构通过IR、1HNMR和元素分析证实;并用偏光显微观察和DSC分析研究了其相变行为,结果表明有8种化合物(M3-6,Ⅵa,b,Ⅴb,Ⅵb)呈现液晶相变。测定了它们的比旋光度。通过X射线衍射研究了化合物Ⅵh120~130℃和Ⅵb170~180℃的近晶结构,Ⅵb显,Ⅵb呈。测定了化合物Ⅳb的电滞回线,证明其具铁电性。 相似文献
104.
105.
Evaporation behavior of water from aqueous dispersions of multihollow particles prepared by the stepwise alkali/acid method 总被引:1,自引:0,他引:1
In order to clarify the formation mechanism of multihollow structures inside styrene–methacrylic acid copolymer particles
prepared by the stepwise alkali/acid method, which we proposed in 1990, the evaporation behavior of water from aqueous dispersions
of the original carboxylated particles and those after the alkali treatment and the stepwise alkali/acid treatments was examined.
It is concluded that the particle after the alkali treatment had a number of small water pools inside.
Received: 22 February 2001 Accepted: 20 June 2001 相似文献
106.
In this paper,p-tricyanovinyl-N,N-dialkylanilines were synthesized as model compounds and through their spectroscopic behavior,the photo-induced electron transfer,charge separation were discussed and the aggregation in DMSO-H_2O system was investigated. 相似文献
107.
We developed a new method to measure the average aggregation number of large rod-like micelles using static fluorescence self-quenching of a solubilized fluorophore. The method is based on the increase of self-quenching of micelle-solubilized pyrene through excimer formation. We consider the effect of random distribution of pyrene in micelles and the micellar size distribution. The measured average aggregation <n> M is based on a new M-weighted raging similar to our exponential-weighted averaging in the transient decay method. We apply this method to study the effect of a large concentration of salt on the average aggregation behavior of sodium dodecyl sulfate (SDS) and cetyle tetraammonium bromide (CTAB). The sizes increase with increasing ionic concentrations. For SDS, we used the thermodynamic model developed by Missel et al. to calculate < n > M which we compare with experimental results. 相似文献
108.
Hal Tasaki 《Journal of statistical physics》1987,49(3-4):841-847
A set of new critical exponent inequalities,d(1 –1 /)2 –, dv(1 – 1/), andd> 1, is proved for a general class of random cluster models, which includes (independent or dependent) percolations, lattice animals (with any interactions), and various stochastic cluster growth models. The inequalities imply that the critical phenomena in the models are inevitably not mean-field-like in the dimensions one, two, and three.The present work was reported at the 56th Statistical Mechanics Meeting (Rutgers, December 1986). 相似文献
109.
We study the two-dimensional first passage problem in which bonds have zero and unit passage times with probabilityp and 1–p, respectively. We prove that as the zero-time bonds approach the percolation thresholdp
c, the first passage time exhibits the same critical behavior as the correlation function of the underlying percolation problem. In particular, if the correlation length obeys(p) ¦p–p
c¦–v, then the first passage time constant satisfies(p)¦p–p
c¦v. At pc, where it has been asserted that the first passage time from 0 tox scales as ¦x¦ to a power with 0<<1, we show that the passage times grow like log ¦x¦, i.e., the fluid spreads exponentially rapidly. 相似文献
110.
The reaction of diethyl 3-ethoxycarbonyl-2-methyl-2-propenylphosphonate (1a) with 3-methylbutanal (2) in heterogeneous MOH (solid)-benzene systems in the presence of 5–10 mol.% of benzyltriethylammonium chloride (BTEAC) gives the reaction product (3) with a higher, for M=K, or lower, for M=Li, ratio of 2E,4E and 2Z,4E-stereoisomers than that observed in the absence of BTEAC. Tetrabutylammonium bromide (TBAB) as a catalyst of the reaction1a + 2 3 in the system KOH (solid)-wet benzene leads to a higher [2E,4E-3][2Z,4E-3] ratio than BTEAC; this ratio grows from 4456 without TBAB to 8020 at 100 mol.% of TBAB. In the latter case the stereochemical outcome of the reaction is similar to that obtained when tetrabutylammonium hydroxide in dry benzene is used as the deprotonating agent. The corresponding diisopropyl phosphonate (1b) and 3,7-dimethyloctanal (4a) interact in the system KOH (solid)-wet benzene-TBAB to give hydroprene (5) containing 88 % of the 2E,4E-isomer (5a) while in the case of 1 equiv. of [(n-Bu4)N]OH in dry benzene the content of5a is 92 %. Diisopropyl 3-isopropoxycarbonyl-2-methyl-2-propenylphosphonate (1c) and 7-methoxy-3,7-dimethyloctanal (4b) under either of these conditions afford methoprene (6) containing 93 % of the 2E,4E-isomer.Part 6, see ref. 1.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1094–1098, June, 1993. 相似文献