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81.
2,3-Disubstituted indoles were synthesized by solid-phase reaction using the Fischer indole synthesis. A "traceless" silicon linker was employed with the silicon-carbon bonding being cleaved with TFA. An oxygen atom was placed into the middle of the spacer/linker so as to enhance solid-phase synthesis by better solvation. 相似文献
82.
83.
A microscopic site binding model to treat binding of several metal ions to multi-center receptors is proposed. The model introduces the appropriate parameterization in terms of microscopic complexation constants and metal-metal pair interaction energies. The model is solved with statistical mechanical techniques, including direct enumeration or transfer matrices. We obtain microscopic and macroscopic complexation constants, microstate probabilities, and binding isotherms for chain-like receptors, including the long-chain limit. Various examples to illustrate the usefulness of the model are given. 相似文献
84.
YoonMee Ham & Sang sup Yum 《偏微分方程(英文版)》1995,8(3):211-218
We consider a free boundary problem in a parabolic partial differential equation with multiple interfacial curves which is reduced to a reaction-diffusion equation. The forcing term of this problem is not continuously differentiable and thus we use Green's function to make a regular one. The existence, uniqueness and dependence. on initial conditions will be shown in this paper. 相似文献
85.
Young Sun Mok Sung Won Ham In-Sik Nam 《IEEE transactions on plasma science. IEEE Nuclear and Plasma Sciences Society》1998,26(5):1566-1574
A mathematical model was proposed to describe the behaviour of the removal of nitrogen oxides (NOx) in a positive pulsed corona discharge reactor. The proposed model takes into account radical production at each pulsing and subsequent radical utilization for NOx removal. The production efficiencies of radicals such as O, OH, H, and N were derived by considering direct electron impact on dissociation of gaseous molecules, followed by excitation transfer reactions of excited oxygen atoms. The production efficiencies of those species were used for the model calculations. The proposed model could adequately predict the experimental data. Of the active species present, the ozone (O3) produced by the reaction of O radical with oxygen was found to play the crucial role in oxidation of NO to NO2 , both theoretically and experimentally 相似文献
86.
In this paper we consider constructing some higher-order modifications of Newton’s method for solving nonlinear equations which increase the order of convergence of existing iterative methods by one or two or three units. This construction can be applied to any iteration formula, and per iteration the resulting methods add only one additional function evaluation to increase the order. Some illustrative examples are provided and several numerical results are given to show the performance of the presented methods. 相似文献
87.
Quantum control of stationary multi-color (MC) light fields in resonant medium with multi-Λ scheme of atomic transition is
proposed. We have found the general analytical solution in the adiabatic limit of quantum evolution resulting from the interaction
of the slow probe light with the new fields generated in the nondegenerate multi-wave mixing scheme. We have found a critical
condition for the stopping and quantum manipulation of the MC-light fields where the united light group velocity can be reduced
down to zero with optimal spectral parameters while preserving the delicate quantum correlations of the initial probe light
pulse. The manipulations, which provide the effective transference of quantum probe light to the new multifrequency light
fields have been analyzed.
The text was submitted by the authors in English. 相似文献
88.
89.
G. E. Ham 《Colloid and polymer science》1978,256(2):201
Ohne Zusammenfassung 相似文献
90.
J.P.C. Kleijnen A.J. van den Burg R.Th. van der Ham 《European Journal of Operational Research》1979,3(1):50-64
The major purpose of this paper is to evaluate the practical use of statistical techniques in both the generalization or analysis of simulation results, and the design of simulation experiments. This problem is investigated with the help of a real-life system, namely the container terminus of ECT in Rotterdam. This system is modeled by a simulation program. The relationship between the simulation response and its input variables is modeled by a linear regression model: metamodel or auxiliary model. The paper summarizes regression analysis including generalized least squares which might be used for simulation responses with non-constant variances. The validity of the postulated regression metamodel is tested statistically: F- and t-statistics. The selection of the situations to be simulated, is done through experimental design methodology, permitting both quantitative and qualitative factors. The statistical techniques apply not only to simulation but also to real-life experiments. 相似文献