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991.
The interaction between vibrational excitation and chemical reactions in high-temperature flows is examined through an example of a typical boundary-layer, i.e. the thermal layer generated by a shock wave reflecting at the end-wall of a shock-tube. During the development of this boundary-layer in space and time, particular features are pointed out, like the existence of a freezing zone close to the wall, responsible of dissociation rate constants remaining significant in this zone where the translational temperature is decreasing. The catalytic role of the wall is also examined and its influence is important on the vibrational temperature profiles and therefore on the rate constants themselves. 相似文献
992.
在NA相依样本条件下,对未知分布函数F(x)的递归核估计进行研究,在适当的条件下,得到了估计的r^-阶平均相合速度,逐点强相合和一致强相合速度,作为应用,讨论了平均剩余寿命函数估计的相合速度。 相似文献
993.
电喷雾质谱法研究人参皂苷与溶菌酶的相互作用 总被引:1,自引:0,他引:1
用电喷雾质谱法研究了溶菌酶与人参皂苷Rg1和Re的非共价相互作用。非共价复合物的解离常数可以由溶菌酶和复合物的峰高直接计算得到。由各个体系得到的溶菌酶与Rg1和Re的一级解离常数KD, 1是一致的,但是二级解离常数KD, 2的差别较大。由此可以推断出复合物的峰高越强,结果的精密度越好。当固定溶菌酶的浓度不变时,复合物的解离常数会随着人参皂苷的浓度的增加而略微的增大。而当固定人参皂苷的浓度时,复合物的解离常数会随着溶菌酶的浓度的增加而减小。计算结果还证明了人参皂苷Rg1与溶菌酶的结合能力大于Re。 相似文献
994.
利用Gausian94量子化学从头算程序,选择UMP2/6-311G方法,对N+2Nen(n=1,2,3)的离子簇合物进行了几何全优化,并通过频率分析确认了体系的稳定构型,得到了各稳定簇合物的离解能.用UHF/6-311G方法,计算了N+2离子在n个氖原子(n=1,2,3)氛围中的转动势垒.计算表明:线性结构是N+2Nen(n=1,2)的最稳定结构;与N+2Hen比较,N+2Nen的诱导电荷更大,束缚势阱更深,各向导性明显,N+2没有在原子氛围中的自由这些计算与Maier实验结果一致. 相似文献
995.
Qin Tian Xian Zhao Xiaozhen Tang Yunxiang Zhang 《Journal of Polymer Science.Polymer Physics》2002,40(12):1236-1244
A series of hydrophobically modified poly(acrylic acid) gels were prepared by the radical copolymerization of acrylic acid and small amounts of hydrophobic comonomers, 2‐(N‐ethylperfluorooctane‐sulfoamido)ethyl methacrylate and lauryl acrylate, in tert‐butanol. The effects of the fractions and species of hydrophobes on hydrophobic association were determined. The hydrophobic association within the hydrophobically modified gels was proven with measurements of swelling and fluorescence as well as Fourier transform infrared spectroscopy. Fluorocarbon‐modified hydrogels showed stronger hydrophobicity than hydrocarbon‐modified hydrogels. © 2002 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 40: 1236–1244, 2002 相似文献
996.
Payne [4] constructed an association scheme from a generalized quadrangle with a quasiregular point. We show that an association scheme with appropriate parameters and satisfying an assumption about maximal cliques must be one of these schemes arising from a generalized quadrangle. 相似文献
997.
Summary The final product of the gamma-radiolysis of tetralithium iron (III) trioxalate chloride nonahydrate has been identified by
M?ssbauer spectroscopy as FeC2O4·2H2O. The radiolytic decomposition proceeds as a first-order process due to the original compound depletion and to the radiolytic
stability of the ferrous compound. Chemical calibration of the relative peaks areas of the two iron species indicates that
the correspondingf-factors ratio is unaffected by the radiolysis.
Paper presented at ICAME-95, Rimini, 10–16, September 1995. 相似文献
999.
针对对象式系统的特点,提出了一种新的测试模型,并以此模型设计了动态测试工具OODT。该工具依据使用事件(USE CASE)生成对象式系统测试过程中的对象关联图(即执行路径)和LOG文件,LOG文件记录执行路径关键点信息。以此实现被测试路径的动态跟踪与执行结果的分析,因此OODT是支持系统的动态测试与测试覆盖率分析的有效工具。 相似文献
1000.
Multidimensional assignment formulation of data association problems arising from multitarget and multisensor tracking 总被引:4,自引:0,他引:4
Aubrey B. Poore 《Computational Optimization and Applications》1994,3(1):27-57
The ever-increasing demand in surveillance is to produce highly accurate target and track identification and estimation in real-time, even for dense target scenarios and in regions of high track contention. The use of multiple sensors, through more varied information, has the potential to greatly enhance target identification and state estimation. For multitarget tracking, the processing of multiple scans all at once yields high track identification. However, to achieve this accurate state estimation and track identification, one must solve an NP-hard data association problem of partitioning observations into tracks and false alarms in real-time. The primary objective in this work is to formulate a general class of these data association problems as multidimensional assignment problems to which new, fast, near-optimal, Lagrangian relaxation based algorithms are applicable. The dimension of the formulated assignment problem corresponds to the number of data sets being partitioned with the constraints defining such a partition. The linear objective function is developed from Bayesian estimation and is the negative log posterior or likelihood function, so that the optimal solution yields the maximum a posteriori estimate. After formulating this general class of problems, the equivalence between solving data association problems by these multidimensional assignment problems and by the currently most popular method of multiple hypothesis tracking is established. Track initiation and track maintenance using anN-scan sliding window are then used as illustrations. Since multiple hypothesis tracking also permeates multisensor data fusion, two example classes of problems are formulated as multidimensional assignment problems.This work was partially supported by the Air Force Office of Scientific Research through AFOSR Grant Numbers AFOSR-91-0138 and F49620-93-1-0133 and by the Federal Systems Company of the IBM Corporation in Boulder, CO and Owego, NY. 相似文献