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81.
82.
本文纠正了Hanai等用开紧连续映射刻画具有σ-点有限基的空间的一个错误,定义了诱导开的弱紧连续映射建立度量空间与具有σ-点有限基空间的映射联系. 相似文献
83.
延迟微分方程单支θ方法的非线性稳定性 总被引:1,自引:0,他引:1
本文讨论了一类延迟量满足Lipschitz条件且最小Lipschitz常数小于 1的非线性变延迟微分方程初值问题 ,得到了带线性插值的单支θ方法的非线性稳定性结果 相似文献
84.
Lin‐Bao Zhang Xin‐Qi Hao Zhan‐Jiang Liu Xin‐Xiang Zheng Shou‐Kun Zhang Jun‐Long Niu Mao‐Ping Song 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2015,127(34):10150-10153
A highly efficient cobalt(II)‐catalyzed alkynylation/annulation of terminal alkynes assisted by an N,O‐bidentate directing group is described. This protocol is characterized by wide substrate scope utilizing cheap cobalt catalysts, and offers a new approach to 3‐methyleneisoindolin‐1‐one, which can be converted into an oxadiazine salt in one step. Moreover, the directing group could be removed in three steps. 相似文献
85.
Lot‐sizing policies for deterioration items under two‐level trade credit with partial trade credit to credit‐risk retailer and limited storage capacity 下载免费PDF全文
Jui‐Jung Liao Kuo‐Nan Huang Kun‐Jen Chung Pin‐Shou Ting Shy‐Der Lin H. M. Srivastava 《Mathematical Methods in the Applied Sciences》2017,40(6):2122-2139
The main purpose of this article is to investigate the optimal wholesaler's replenishment decisions for deterioration items under two levels of the trade credit policy and two storage facilities in order to reflect the supply chain management situation within the economic order quantity framework. In this study, each of the following assumptions have been made: (1) The own warehouse with limited capacity always is not sufficient to store the order quantity, so that a rented warehouse is needed to store the excess units over the capacity of the own warehouse; (2) The wholesaler always obtains the partial trade credit, which is independent of the order quantity offered by the supplier, but the wholesaler offers the full trade credit to the retailer; (3) The wholesaler must take a loan to pay his or her supplier the partial payment immediately when the order is received and then pay off the loan with the entire revenue. Under these three conditions, the wholesaler can obtain the least costs. Furthermore, this study models the wholesaler's optimal replenishment decisions under the aforementioned conditions in the supply chain management. Two theorems are developed to efficiently determine the optimal replenishment decisions for the wholesaler. Finally, numerical examples are given to illustrate the theorems that are proven in this study, and the sensitivity analysis with respect to the major parameters in this study is performed. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
86.
Bor Yuan Lin Moo Been Chang Hsin Liang Chen How Ming Lee Sheng Jen Yu Shou Nan Li 《Plasma Chemistry and Plasma Processing》2011,31(4):585-594
The feasibility of C3F8 abatement via combining nonthermal plasma with adsorption and/or catalysis is investigated in this study. In terms of the simultaneous combination of plasma, adsorption and catalysis (CPAC), three different configurations including A/C layer (adsorbent layer prior to catalyst layer), C/A layer (catalyst layer prior to adsorbent layer) and A/C mixture (adsorbent and catalyst are mechanically mixed) are adopted. For all the experimental tests conducted in this study, the gas stream consists of 500 ppm C3F8, 2% O2, and balanced N2. The experimental results indicate that C3F8 removal efficiencies depend on what kind of packing material is adopted (adsorbent, catalyst or both) and how the material is packed within the plasma reactor. The removal efficiencies obtained with different reactors are in the order as: CPAC (A/C layer; AC mixture) > CPA (plasma with adsorbent alone) > CPC (plasma with catalyst alone) > CPAC (C/A layer). The indentified products after treatment include CO2, CO, N2O and CF4. The formation of C2F6 is not observed in this study, which is encouraging since the global warming potential of C2F6 is actually higher than that of C3F8. 相似文献
87.
本文给出了带正则*-断面的正则半群的若干性质,获得了带拟理想正则*-断面的正则半群的一个构造方法.利用这一构造定理,考虑了这类半群上的同余. 相似文献
88.
The reaction of the thiocarbamoyl‐molybdenum complex [Mo(CO)2(η2‐SCNMe2)(PPh3)2Cl] 1 , with EtOCS2K and C4H8NCS2NH4 in dichloromethane at room temperature yielded the seven coordinated ethyldithiocarbonate thiocarbamoyl‐molybdenum complex [Mo(CO)2(η2‐S2COEt)(η2‐SCNMe2)(PPh3)] 2 , and the dithiocarbamate thiocarbamoyl‐molybdenum complex [Mo(CO)2(η2‐S2CNC4H8)(η2‐SCNMe2)(PPh3)] 3 . The geometry around the metal atom of compounds 2 and 3 are capped octahedrons as revealed by X‐ray diffraction analyses. The thiocarbamoyl and ethyldithiocarbonate or pyrrolidinyldithiocarbamate ligands coordinate to the molybdenum metal center through the carbon and sulfur and two sulfur atoms, respectively. Structure parameters, NMR, IR and Mass spectra are in agreement with the crystal chemistry of the two compounds. 相似文献
89.
Chien‐Chih Chen Pai‐Chieh Cheng Shou‐Ling Huang Prof. Dr. Ying‐Chih Lin Yi‐Hong Liu 《化学:亚洲杂志》2011,6(11):3122-3131
Two cyclopropyl allenylidene complexes [Ru]=CCC(R)(C3H5) ([Ru]=[RuCp(PPh3)2], Cp=Cyclopentadienyl; R=thiophene ( 2a ) and R=Ph ( 2b )) are prepared from the reactions of [Ru]Cl with the corresponding 1‐cyclopropyl‐2‐propyn‐1‐ol in the presence of KPF6. Thermal treatment, halide‐anion addition, and palladium‐catalyzed reactions of 2a and 2b all lead to a ring expansion of the cyclopropyl group, giving the vinylidene complexes 4a and 4b , respectively, each with a five‐membered ring. This ring expansion proceeds by C C bond formation between Cβ of the cumulative double bond and a methylene group of the cyclopropyl ring. In the reaction of 2a with pyrrole, consecutive formation of two C C bonds, one between C‐2 of pyrrole and Cγ of 2a and the other between C‐3 of pyrrole and Cα, results in the formation of 6a . The reaction proceeds by addition of pyrrole and 1,3‐proton shifts. The hydrogenation of 2a by NaBH4 is carried out in different solvents. The cumulative double bonds are reduced regioselectively to give a mixture of 7a and 8a . Interestingly, use of different solvents leads to different ratios of 7a and 8a . Presence of a protic solvent like methanol in dichloromethane or chloroform solution increases the yield of 8a , thus revealing that both the rates of hydroboration and deboronation increase. The structures of two new complexes 4a and 6a have been firmly established by X‐ray diffraction analysis. 相似文献
90.
Let A = (aij)n × n be an invertible matrix and A−1 = (aij)n × n be the inverse of A. In this paper, we consider the generalized Liouville system (0.1) where 0 < hj ∈ C1(M) and \input amssym $\rho_j \in \Bbb R^+$ , and prove that, under the assumptions of (H1) and (H2) (see Introduction), the Leray‐Schauder degree of (0.1) is equal to if ρ = (ρ1, …, ρn) satisfies Equation (0.1) is a natural generalization of the classic Liouville equation and is the Euler‐Lagrangian equation of the nonlinear function Φρ: The Liouville system (0.1) has arisen in many different research areas in mathematics and physics. Our counting formulas are the first result in degree theory for Liouville systems. © 2010 Wiley Periodicals, Inc. 相似文献