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361.
A multi-level solution method is presented for multi-objective optimization of large-scale systems associated with the hierarchical structure of decision-making. The method, consisting of a multi-level problem formulation and an interactive algorithm, has distinct advantages in handling the difficulties which are often experienced in engineering. The method is illustrated by its application to an optimal design of a processing system. 相似文献
362.
A simple direct radioimmunoassay for 11-deoxycortisol in serum is described. A new type of bridge heterologous 125I labeled 11-deoxycortisol was prepared and was applied to the direct radioimmunoassay. Low and high levels of 11-deoxycortisol in serum were sensitively determined by the direct radioimmunoassay. 相似文献
363.
Inside Cover: Activation of Dihydrogen by Masked Doubly Bonded Aluminum Species (Angew. Chem. Int. Ed. 41/2016)
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364.
Norihiro Kamide 《Mathematical Logic Quarterly》2016,62(3):177-189
In this paper, the positive fragment of the logic of contraction‐less relevant implication is extended with the addition of a paraconsistent negation connective similar to the strong negation connective in Nelson's paraconsistent four‐valued logic . This extended relevant logic is called , and it has the property of constructible falsity which is known to be a characteristic property of . A Gentzen‐type sequent calculus for is introduced, and the cut‐elimination and decidability theorems for are proved. Two extended Routley‐Meyer semantics are introduced for , and the completeness theorems with respect to these semantics are proved. 相似文献
365.
The unimolecular reaction dynamics of hydrogen cyanide (HCN) induced by IR multiphoton, femtosecond excitations was studied on the basis of the nuclear wavepacket theory. Both hydrogen dissociation and migration of HCN are taken into account. In evaluating the propagation of the wavepackets in the two-dimensional potential surface, position grid and eigenfunction basis sets were adopted for the dissociation and hydrogen migration coordinates, respectively. The ground state potential energy function and the dipole moment function calculated by using a MCSCF ab-initio procedure were used. Laser-intensity dependencies of the dissociation and hydrogen migration probabilities were evaluated. Effects of mode-couplings on the hydrogen migration were examined. 相似文献
366.
Ab initio calculations were performed to study the molecular structures and the vibrational levels of the low-lying ionic states (2B1, 2A1 and 2B2) of hydrogen sulphide. The equilibrium molecular structure and the vibrational analysis of these states are presented. The normal vibrational calculations at the RHF level and more extensive calculations at the SDCI level using the explicit vibrational Hamiltonians were used for the vibrational analysis. The theoretical ionization intensity curves including the vibrational structures of these ionic states are also presented and compared with the photoelectron spectrum. The results show that the global shape of the potential energy surface has to be taken into consideration in order to analyze the 2A1 and 2B2 states. A new assignment of the photoelectron spectra of H2S is proposed. 相似文献
367.
Ikemoto N Tellers DM Dreher SD Liu J Huang A Rivera NR Njolito E Hsiao Y McWilliams JC Williams JM Armstrong JD Sun Y Mathre DJ Grabowski EJ Tillyer RD 《Journal of the American Chemical Society》2004,126(10):3048-3049
Pure (Z)-enamines readily prepared from beta-ketoesters and amides using (S)-phenylglycine amide were hydrogenated with very high diastereoselectivities (up to 200:1) using heterogeneous catalysis. Hydrogenolytic cleavage of the (S)-phenylglycine amide afforded the corresponding chiral beta-aminoesters and amides. The high geometrical purity of the (Z)-enamine and a simple activation procedure for the PtO2 catalyst are essential in achieving high selectivity. 相似文献
368.
369.
Tomohiro Sugahara Dr. Jing‐Dong Guo Prof. Dr. Takahiro Sasamori Prof. Dr. Shigeru Nagase Prof. Dr. Norihiro Tokitoh 《Angewandte Chemie (International ed. in English)》2018,57(13):3499-3503
The catalytic activation of small neutral molecules followed by the formation of C?C bonds is a highly important method to increase the complexity and/or value of simple starting materials. Reported is an isolable digermyne, a compound with a Ge≡Ge bond, which acts as a precatalyst for the cyclotrimerization of terminal arylacetylenes to afford the corresponding 1,2,4‐triarylbenzenes with absolute regioselectivity. The results demonstrate that bespoke main‐group‐element compounds can catalytically activate and transform small neutral organic molecules and induce the formation of C?C bonds. 相似文献
370.
A kinetically stabilized 9-silaanthracene (1) underwent unique photochemical and thermal reactions to afford 9,10-Dewar-9-silaanthracene 2a and the head-to-tail [4 + 4] dimer 3, respectively. The structure of 2a was confirmed by 1H, 13C, and 29Si NMR spectra, and the kinetic parameters for the thermal reversion of 2a to 1 were obtained by the measurement of UV/vis spectra. The dimer 3 was thermally stable, and the molecular structure of 3 was determined by X-ray crystallographic analysis. It was experimentally demonstrated for the first time that 9-silaanthracene, as well as anthracene, can afford either the Dewar isomer or [4 + 4] dimer, depending on the reaction conditions. 相似文献