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71.
热效应对光折变晶体两波耦合的特性影响的理论分析 总被引:3,自引:1,他引:2
用一种模型对两波耦合进行了分析,导出了强度相位的解析式,对影响两波耦合的参数进行了理论分析。分析了对BaTiO3光折变晶体的两波耦合的测量结果。 相似文献
72.
It is conceptually proposed that the total entropy of polymer solution is contributed from two distinct parts: the positional and the oomformational. The former can be represented analytically, while the latter can be simulated with the random self-avoiding walk model on the simple cubic lattice for multichain systems. The obtained results indicated that both the conformational entropy and the mixing heat are consistent with the scaling laws wry well. 相似文献
73.
74.
In a general measure-theoretic context, it is proved that the action of a stochastic map on a pair of probability distributions can be characterized by the criterion of decreasing mixing distance. 相似文献
75.
Mordechai I. Henig 《Mathematical Programming》1990,46(1-3):205-217
In the absence of a clear objective value function, it is still possible in many cases to construct a domination cone according to which efficient (nondominated) solutions can be found. The relations between value functions and domination cones and between efficiency and optimality are analyzed here. We show that such cones must be convex, strictly supported and, frequently, closed as well. Furthermore, in most applications potential optimal solutions are equivalent to properly efficient points. These solutions can often be produced by maximizing with respect to a class of concave functions or, under convexity conditions, a class of affine functions. 相似文献
76.
Donald R. Schreiber James Huebner Seyed Rahmani Frank J. Millero 《Journal of solution chemistry》1993,22(3):201-210
Enthalpies of mixing (m
H) aqueous solutions of CoCl2, CuCl2, and MnCl2 with NaCl solutions were measured at constant ionic strengths of 0.5, 1.0, and 3.0 molal at 25°C. The excess enthalpy equations of Pitzer were then fit to the resulting m
H data. The resulting parameters are the temperature derivatives of the activity coefficient mixing parameters in the Pitzer system. The heat of mixing data for CoCl2 and CuCl2 were in agreement with earlier isomolal results by other workers. 相似文献
77.
用马来酸二丁酯(DBM)为接枝单体,过氧化二枯基(DCPO)为引发剂,对低密度聚乙烯(LDPE)进行了熔融接枝功能化。样品的红外光谱表明接枝反应确已发生。通过对样品中酯基的皂化水解测定产物的接枝率,对产物进行萃取,用凝胶量间接表征产物的交联程度;用溶液的特性粘度从侧面显示样品的支化或降解情况。实验结果表明,产物的接枝率和凝胶量可以通过选择反应条件(温度、时间及反应混合物的组成)来控制;过量的DCPO是引起交联产生凝胶的主要原因;向体系中添加DMF可阻止交联反应的发生,但产物的接枝率也有所下降,以自由基机理对上述结果进行了讨论。 相似文献
78.
镀铜铁屑-H_2O_2催化氧化降解含酚废水 总被引:2,自引:0,他引:2
采用镀铜铁屑代替传统Fenton体系中的FeSO4作为催化剂,通过改变H2O2与镀铜铁屑的投加量、溶液的pH值、反应温度、反应时间等条件,研究了该体系对处理苯酚废水的影响。结果表明,常温下处理实际含酚印染废水,在pH值为4~6,30%H2O2 12mL/L,镀铜铁屑5g/L,反应时间为45min时,COD去除率可达96%,其CODCr从5827mg/L降至419mg/L,色度从2000降至30,符合国家三级排放标准。 相似文献
79.
Summary Inverse gas chromatography is shown to be suitable for the study of the oxidation of vegetable oils. With air as carrier gas
characteristic plots of retention index versus time are obtained for hydroxylic test solutes that are consistent with the
oxidation behaviour of vegetable oils. Shifts of retention are found to be accompanied by changes of column efficiency due
to the oxidative crosslinking of polyunsaturated vegetable oils. The technique also leads to useful information concerning
the oxidation of antioxidant inhibited systems.
Presented at the 15th International Symposium on Chromatography, Nürnberg, October 1984 相似文献
80.
Summary To match the need of high efficiency capillary column (plate number N2, Plate height H2 and carrier gas linear velocity U2), a new high efficiency packed column (N1, H1 and U1) at high carrier gas velocity with small capacity factor has been developed in the light of theoretical discussion of factors
effecting the column efficiency utilization ratio. 相似文献