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181.
Ducouret G Chassenieux C Martins S Lequeux F Bouteiller L 《Journal of colloid and interface science》2007,310(2):624-629
The rheological properties of hydrogen bonded reversible aggregates in apolar solvent have been investigated. The zero shear viscosity, the plateau modulus and the terminal viscoelastic relaxation time exhibit power laws dependencies with the concentration that have been compared with the behaviours expected for reversible polymers. It appears that the dynamics originate from scission/recombination mechanisms. Moreover, the growth of the aggregates with concentration follows the laws observed and predicted for worm-like micelles at low concentrations allowing the length of the aggregates to be estimated 500 nm at 3 g L(-1). However, at the highest concentrations investigated, deviations from the power laws suggest the presence of some intrinsic chain stopper poisons in the solutions. 相似文献
182.
B.M. Roehner 《The European Physical Journal B - Condensed Matter and Complex Systems》2000,13(1):175-187
It is a common belief nowadays that the world economy is fairly well “integrated”. Yet, this belief often turns out to be
in contradiction with empirical evidence. As a matter of fact the way distant markets interact is a question that has largely
been ignored by economists. In this series of two papers we examine the role that space, that is to say geographical distance,
plays in the economics of commodity markets. The first of these papers presents the empirical evidence while the second develops
a theoretical framework. The empirical enquiry discloses several noteworthy features, e.g. (i) with respect to spatial interaction there is a sharp contrast between stock markets and commodity markets. While there
is almost perfect spatial arbitrage in the first case, this is not true for commodity markets. (ii) In spite of their chaotic
behavior in the course of time commodity prices display well defined spatial patterns, (iii) as in statistical physics and
fluid dynamics interactions can be described in terms of correlation length. The correlation length of a set of markets is
seen to increase along with the number of transactions; it also increases when transport costs decline as was the case during
the “transportation revolution” of the mid-nineteenth century. Using the notion of correlation length one is able to give
a quantitative meaning to the otherwise ill-defined concept of market integration.
Received 17 May 1999 and Received in final form 31 May 1999 相似文献
183.
丙烯酰胺-二氰二胺大单体及其与苯乙烯共聚物的研究(Ⅱ)——共聚物与甲基橙及其同系物的相互作用 总被引:1,自引:0,他引:1
用平衡渗析法研究了主链含疏水基、侧链含亲水基的接枝共聚物P-M-St和二氰二胺同甲醛、氧化铵的缩合物D-F与甲基橙MO及乙基橙EO,橙黄ⅣO-Ⅳ相互作用的热力学.由Klotz方程求得键合常数K1和△G、△H和△S.D-F与P-M-St相比,其与MO的键合作用较弱.P-M-St与染料的键合程度:O-Ⅳ>EO>MO.脲或甲醇能削弱高聚物与染料的相互作用. 相似文献
184.
AbInitioStudiesontheStructureandBindingInteractionofM+CO2(M=Sc,Ti…Zn)*FANHong-Jun,ZHONGShi-Jun,LIUChun-Wan**(FujianInstituteo... 相似文献
185.
用共沉淀法制备了以Keggin结构为骨架的不同反荷离子钼磷酸盐,利用FTIR、XRD等手段进行了表征。结果表明,Li、Na、K、Cs分别作为反荷离子时的杂多酸盐的热稳定性依次增强,并考察了催化剂对异丁醛一步氧化制甲基丙烯酸的催化活性,其中Cs盐的催化活性最优。 相似文献
186.
B. Lobe W. Janke K. Binder 《The European Physical Journal B - Condensed Matter and Complex Systems》1999,7(2):283-291
We analyze recently extended high-temperature series expansions for the “Edwards-Anderson” spin-glass susceptibility of the
p-state Potts glass model on d-dimensional hypercubic lattices for the case of a symmetric bimodal distribution of ferro- and antiferromagnetic nearest-neighbor
couplings . In these star-graph expansions up to order 22 in the inverse temperature , the number of Potts states p and the dimension d are kept as free parameters which can take any value. By applying several series analysis techniques to the new series expansions,
this enabled us to determine the critical coupling Kc and the critical exponent of the spin-glass susceptibility in a large region of the two-dimensional (p,d)-parameter space. We discuss the thus obtained information with emphasis on the lower and upper critical dimensions of the
model and present a careful comparison with previous estimates for special values of p and d.
Received: 25 May 1998 / Revised and Accepted: 11 August 1998 相似文献
187.
A.K. Hartmann U. Nowak 《The European Physical Journal B - Condensed Matter and Complex Systems》1999,7(1):105-109
We investigate the critical behavior of three-dimensional random-field Ising systems with both Gauss and bimodal distribution
of random fields and additional the three-dimensional diluted Ising antiferromagnet in an external field. These models are
expected to be in the same universality class. We use exact ground-state calculations with an integer optimization algorithm
and by a finite-size scaling analysis we calculate the critical exponents , , and . While the random-field model with Gauss distribution of random fields and the diluted antiferromagnet appear to be in same
universality class, the critical exponents of the random-field model with bimodal distribution of random fields seem to be
significantly different.
Received: 9 July 1998 / Received in final form: 15 July 1998 / Accepted: 20 July
1998 相似文献
188.
本文通过一个简单的模型证明了有偿付约束的无限期资产经济均衡存在性,所用条件与已有文献相比更加简明.这一研究可望为我们今后研究无限期经济提供方向:同时也可以更好地理解偿付约束(或保证金制度)在资本市场中的作用 相似文献
189.
190.
交联低密度聚乙烯交联程度表征方法的研究 总被引:2,自引:0,他引:2
硅烷交联法和过氧化物交联法是聚乙烯交联改性的两种重要方法[1],以往的文献上通常都以凝胶含量来表征这两种方法制备的交联产物的交联程度[2~6],但是在实践中我们发现,凝胶含量基本相同的硅烷交联聚乙烯和过氧化物交联聚乙烯的性能存在着很大的差异,例如在70℃的二甲苯中凝胶含量为62%的过氧化物交联低密度聚乙烯(LDPE)的平衡溶胀比是相同凝胶含量的硅烷交联LDPE的4倍,150℃时凝胶含量为70%的硅烷交联聚乙烯的热延伸率比相同凝胶含量的过氧化物交联聚乙烯小三倍,而且二者的结晶行为和结晶度也有很大的… 相似文献