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91.
Zhensheng Yu Yangchen Liu Xinyue Gan 《Numerical Functional Analysis & Optimization》2017,38(11):1458-1472
This paper presents a nonmonotone inexact Newton-type method for the extended linear complementarity problem (ELCP). We first reformulate the optimization system of the ELCP problem into a system of smoothed equations. Then we solve this system by a nonmonotone inexact Newton-type algorithm. The global convergence is obtained and numerical tests for some classes of ELCP include linear complementarity, horizontal linear complementarity, and generalized linear complementarity problems are also given to show the e?ciency of the proposed algorithm. 相似文献
92.
分析归纳了国际市场营销管理与信息的特征,把系统目标分解为三级,依此提出的国际市场营销管理与决策信息系统结构模式,充分考虑了计算机在企业管理中应用的优势与特点,同时又考虑到国情,便于企业开发实施。 相似文献
93.
B值随机元阵列加权和的收敛性与大数定律 总被引:6,自引:0,他引:6
甘师信 《武汉大学学报(理学版)》1997,(5)
令{Xni,1≤i≤kn↑∞,n≥1}为B值随机元阵列,{ani,1≤i≤kn,n≥1}为实数阵列.讨论加权和Sn=kni=1aniXni,n≥1的收敛性.在条件supn,iP(Xni>x)=0(x-r)下给出了一些收敛性结果(1≤r<p≤2),同时用这种收敛性刻划了Banach空间的p型性质 相似文献
94.
Wenbo Huang Liqiao Shi Manli Liu Zhigang Zhang Fang Liu Tong Long Shaohua Wen Daye Huang Kaimei Wang Ronghua Zhou Wei Fang Hongtao Hu Shaoyong Ke 《Molecules (Basel, Switzerland)》2022,27(5)
Primary arylsulfonamide functional groups feature prominently in diverse pharmaceuticals. However, natural arylsulfonamides are relatively infrequent. In this work, two novel arylsulfonamide natural products were first synthesized, and then a series of novel molecules derived from natural arylsulfonamides were designed and synthesized, and their in vitro cytotoxic activities against A875, HepG2, and MARC145 cell lines were systematically evaluated. The results indicate that some of these arylsulfonamide derivatives exhibit significantly good cytotoxic activity against the tested cell lines compared with the control 5-fluorouracil (5-FU), such as compounds 10l, 10p, 10q, and 10r. In particular, the potential molecule 10q, containing a carbazole moiety, exhibited the highest inhibitory activity against all tested cell lines, with IC50 values of 4.19 ± 0.78, 3.55 ± 0.63, and 2.95 ± 0.78 μg/mL, respectively. This will offer the potential to discover novel drug-like compounds from the sparsely populated area of natural products that can lead to effective anticancer agents. 相似文献
95.
Photoactivatable analogues 4-6 of cholesterol (1), having their cross-linking site in the ring D sterol region, have been synthesized starting from bromotetralone 14 via enantioselective Robinson annulation to enone 13 and Suzuki carbonylative coupling to the appropriate phenylboronic acid. Each of 4-6 was shown to substitute successfully for 1 in an assay of apo A-I-induced cellular cholesterol efflux, indicating that these analogues equilibrated with 1 in all major cellular pools. 相似文献
96.
Many chiral pesticides exhibit enantioselectivity in biotransformation and ecotoxicity in the environment. A significant class of chiral pesticides is imidazolinone herbicides, of which enantioselectivity has not been well studied. Development of efficient chiral separation methods is the first step for allowing characterization of enantioselectivity in environmental processes. In this study, we attempted to resolve enantiomers of imidazolinone herbicides using reversed-phase and normal-phase high-performance liquid chromatography with polysaccharide-type chiral columns. Enantiomers of imazethapyr, imazaquin, and imazamox were separated on a Chiralcel OD-R column using 50mM phosphate buffer-acetonitrile as mobile phase. Enantiomers of imazapyr, imazapic, imazethapyr, imazamox and imazaquin were resolved on a Chiralcel OJ column using n-hexane (0.1% trifluoroacetic acid)-alcohol as mobile phase. The enantiomers of five methyl derivatives of imidazolinone herbicides were also resolved on the Chiralcel OJ column. The Deltak' values revealed a structure-enantioselectivity relationship for the separation behaviors of the enantiomers on the OJ column. The described method was successfully applied for chiral analysis of two imidazolinone herbicides (imazapyr and imazaquin) in spiked soil samples. 相似文献
97.
In this paper, a generalized JKR model is investigated, in which an elastic cylinder adhesively contacts with an elastic half space and the contact region is assumed to be perfect bonding. An external pulling force is acted on the cylinder in an arbitrary direction. The contact area changes during the pull-off process, which can be predicted using the dynamic Griffith energy balance criterion as the contact edge shifts. Full coupled solution with an oscillatory singularity is obtained and analyzed by numerical calculations. The effect of Dundurs' parameter on the pull-off process is analyzed, which shows that a nonoscillatory solution can approximate the general one under some conditions, i.e., larger pulling angle (pi/2 is the maximum value), smaller a/R or larger nondimensional parameter value of Deltagamma/E*R. Relations among the contact half width, the external pulling force and the pulling angle are used to determine the pull-off force and pull-off contact half width explicitly. All the results in the present paper as basic solutions are helpful and applicable for experimenters and engineers. 相似文献
98.
A new series of cellulose-graft-poly(N-isopropylacrylamide)(cellulose-g-PNIPAM) copolymers were prepared by atom transfer radical polymerization(ATRP) of N-isopropylacrylamide monomers from a cellulose-based macro-initiator, which was homogeneously synthesized in an ionic liquid 1-allyl-3-methylimidazolium chloride(Amim Cl). The composition of cellulose-g-PNIPAM copolymers could be adjusted by altering the feeding ratio and reaction time. The resultant copolymers with relatively high content of PNIPAM segments(molar substitution of PNIPAM ? 18.3) were soluble in water at room temperature. Aqueous solutions of cellulose-g-PNIPAM copolymers exhibited clear temperature-sensitive behavior, and their sol-to-gel phase transition properties were investigated by dynamic light scattering(DLS) and UV measurements. Compared with pure PNIPAM, the cellulose-g-PNIPAM copolymers possessed higher lower critical solution temperatures(LCST) in a range from 36.9 ?C to 40.8 ?C, which are close to normal human body temperature, and could be tuned by adjusting the content of PNIPAM segments in copolymers. Spherical structure of cellulose-g-PNIPAM copolymers formed at temperatures above LCST and its morphology was observed by TEM and SEM. These novel cellulose-g-PNIPAM copolymers may be attractive substrates for some biomedical applications, such as drug release and tissue engineering. 相似文献
99.
(17)O-(1)H double resonance NMR spectroscopy was used to study the local structure of zeolite H-Mordenite. Different contact times were used in cross-polarization magic angle spinning (CPMAS) NMR, CP rotational-echo double resonance (CP-REDOR) NMR, and heteronuclear correlation (HETCOR) NMR spectroscopy to distinguish between Br?nsted acid sites with different O-H distances. The accessibility of the various Br?nsted acid sites was quantified by adsorbing the basic probe molecule trimethylphosphine in known amounts. On the basis of these experiments, locations of different Br?nsted acid sites in H-Mordenite (H-MOR) were proposed. The use of (17)O chemical shift correlations to help assign sites is discussed. 相似文献
100.
Xie S Lu X Zhai T Gan J Li W Xu M Yu M Zhang YM Tong Y 《Langmuir : the ACS journal of surfaces and colloids》2012,28(28):10558-10564
We report the synthesis of Zn(x)Cd(1-x)S@ZnO nanorod arrays via a facile two-step process and the implementation of these core-shell nanorods as an environmental friendly and recyclable photocatalyst for methyl orange degradation. The band gap of Zn(x)Cd(1-x)S@ZnO core-shell nanorods can be readily tunable by adjusting the ratio of Zn/Cd during the synthesis. These Zn(x)Cd(1-x)S@ZnO core-shell nanorods exhibit a high photocatalytic activity and good stability in the degradation of the methyl orange. Moreover, these films grown on FTO substrates make the collection and recycle of the photocatalyst easier. These findings may open new opportunities for the design of effective, stable, and easy-recyclable photocatalytic materials. 相似文献