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Online uniform machine covering with the known largest size

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Progress in Natural Science:Materials International 2007年第11期17卷 1271-1278页

作者： Cao Shunjuan1,2.and Tan Zhiyi1,3.1. department of Mathematics, Zhejiang {2., Hangzhou 3.002., China 2. department of Mathematics, Zhejiang Forestry {2., Hangzhou 3.13.0, China 3. State Key Laboratory of CAD & CG, Zhejiang {2., Hangzhou 3.002., China) department of Mathematics Zhejiang University Hangzhou 310027 China department of Mathematics Zhejiang Forestry University Hangzhou 311300 China State Key Laboratory of CAD & CG Zhejiang University Hangzhou 310027 China

This paper investigates the semi-online scheduling problem with the known largest size on two uniform machines. The objective is to maximize the minimum machine completion time. Both lower bounds and algorithms are given. Algorithms are optimal for the majority values of s≥1, where s is the speed ratio of the two machines. The largest gap between the competitive ratio and the lower bound is about 0.064. Moreover, the overall competitive ratio 2.matches the overall lower bound.

关键词： scheduling and covering uniform machine design and analysis of algorithm online competitive ratio

The regular representation and regular covariant representation of crossed products of Woronowicz C^(*)-algebras

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Science China Mathematics 2005年第9期48卷 1245-1259页

作者： ZHANG Xiaoxia~(1,2. & GUO Maozheng~(1,3. 1. School of Mathematical Sciences,Peking university,Beijing 100871,China 2. {2. of Mathematics,Yantai university,Yantai 2.4005,China 3. LMAM,Peking university,Beijing 100871,China School of Mathematical Sciences Peking University Beijing China department of Mathematics Yantai University Yantai China LMAM Peking University Beijing China

In this paper,it is shown that the regular representation and regular covariant representation of the crossed products A×α G correspond to the twisted multiplicative unitary operators,where A is a Woronowicz C~*-algebra acted upon by a discrete group ***,it is also shown that the regular covariant C~*-algebra is the Woronowicz C~*-algebra which corresponds to a multiplicative ***,an explicit description of the multiplicative unitary operator for C(SU_q(2. )×α (?) is given in terms of those of the Woronowicz C~*-algebra C(SU_q(2. ) and the discrete group G.

关键词： multiplicative unitary operator, Woronowicz C*-algebra, crossed product.

Parabolic equation of the m-Laplacian with nonlinear boundary condition

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Chinese Science Bulletin 1998年第11期43卷 905-908页

作者： WANG Shu+ 1, 2. WANG Mingxin 3. XIE Chunhong 1 1. department of Mathematics, Nanjing {2., Nanjing 2.0093. China 2. department of Mathematics, Henan {2., Kaifeng 475001, China 3. department of Applied Mathematics, Southeast {2., department of Mathernntics Nanjing University Nanjing China department of Mathematics Henan University Kaifeng China department of Applied Mathematics Southeast University Nanjing China

The existence and nonexistence of global positive weak solutions of parabolic equation of the m-Laplician with nonlinear boundary condition are dealt with. The necessary and sufficient conditions on the existence of a... 详细信息

关键词： nonlinear boundary condition parabolic equation of m-Laplacian global solution blow-up.

Effect of D-allethrin on proteinase activity in the midgut of the spider Pardosa pseudoannulata detected by bulk acoustic wave impedance technique

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Progress in Natural Science:Materials International 2007年第12期17卷 1521-1526页

作者： Wang Zhi1, Fu Xiuqin2. Rao Liqun1 and Lu Xiangyang1(1. College of Bioscience & Biotechnology, hunan Agriculture university, {2. 41012., China 2. College of Life Science, hunan Normal university, {2. 410081, China) College of Bioscience & Biotechnology Hunan Agriculture University Changsha 410128 China College of Life Science Hunan Normal University Changsha 410081 China

The piezoelectric bulk acoustic wave (BAW) impedance analysis method was employed to monitor in situ the proteinase-catalyzed hydrolyzation of casein and the effect of pesticide D-allethrin on the proteinase activity in the midgut of the spider Pardosa pseudoannulata, and the results obtained were verified by ultraviolet spectroscopy. The hydrolyzation was significantly increased in the presence of low-dose D-allethrin, whereas significantly inhibited in the presence of high-dose D-allethrin, and a correlation was found precisely between the enzyme activity reflected by the final frequency shift after the hydrolyzation and the concentration of D-allethrin, with a significant frequency response observed even at a 1.5×10-5 volume ratio of D-allethrin to distilled water. The present work may have presented a novel method feasible for study on the mechanism of excitability of spiders under low-dose D-allethrin pesticide and quick detection of proteinase activity.

关键词： Pardosa pseudoannulata D-allethrin proteinase activity ultraviolet spectroscopy piezoelectric bulk acoustic wave impedance method.

Local and non-local sources of airborne particulate pollution at Beijing——The ratio of Mg/Al as an element tracer for estimating the contributions of mineral aerosols from outside Beijing

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Science China chemistry 2005年第3期48卷 253-264页

作者： HAN Lihui1, ZHUANG Guoshun1,2.3. SUN Yele1 & WANG Zifa3.1. The Center for Atmospheric Environmental Study, {2. of chemistry, Beijing Normal university, Beijing 100875, China 2. Center for Atmospheric chemistry Study, {2. of Environmental Science & Engineering, Fudan university, Shanghai 2.043., China 3. LAPC/NZC, Institute of Atmospheric Physics, CAS, Beijing 10002., China The Center for Atmospheric Environmental Study Department of Chemistry Beijing Normal University Beijing China Center for Atmospheric chemistry Study Department of Environmental Science & Engineering Fudan University Shanghai China Institute of Atmospheric Physics CAS LAPC/NZC Beijing China

A new element tracer technique has firstly been established to estimate the contri-butions of mineral aerosols from both inside and outside Beijing. The ratio of Mg/Al in aerosol is a feasible element tracer to distinguish between the sources of inside and outside Beijing. Mineral aerosol, inorganic pollution aerosol mainly as sulfate and nitrate, and organic aerosol are the major components of airborne particulates in Beijing, of which mineral aerosol accounted for 3.%―67% of total suspended particles （TSP）, 10%―70% of fine particles （PM2.5）, and as high as 74% and 90% of TSP and PM2.5, respectively, in dust storm. The sources from outside Beijing contributed 62. （3.%―86%） of the total mineral aerosols in TSP, 69% （52.―90%） in PM10, and 76% （59%―93.） in PM2.5 in spring, and 69% （52.―83.）, 79% （52.―93.）, and 45% （7%―79%） in TSP, PM10, and PM2.5, respectively, in winter, while only2.% in summer and autumn. The sources from outside Beijing contributed as high as 97% during dust storm and were the dominant source of airborne particulates in Beijing. The contributions from outside Bei-jing in spring and winter are higher than those in summer, indicating clearly that it was related to the various meteorological factors.

关键词： mineral aerosol local sources non-local sources dust storm re-suspended dust element tracer technique.

Morphology and electrical conductivity of PACS

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Journal of Environmental Sciences 2000年第3期12卷 319-324页

作者： GAO Bao\|yu\+1, LIU Zong\|gang\+2. YUE Qin\|yan\+3. ZHAO Hua\|zhang\+3.(1. {2. of Environmental Engineering, Shandong university, Jinan 2.0100, China 2. Environmental Monitoring Station of Huaiyin, Jinan 2.002., China 3. {2. of Environ 山东大学山东济南 2 50 1 0 0 山东济南市槐荫区环境监测山东济南 2 50 0 2 2

Polyaluminium chlorides with sulfate ion(PACS) were prepared by using AlCl 3.6H 2., Al(SO 4) 3.18H 2. and Na 2.O 3.as raw materials. The effects of basicity ( r ), Al 3. /SO 4 2. molar ratio and aging time on the morphology of PACS were observed by transmission electrical microscope. The influence of aging time on charge neutralization and coagulation effect of PACS was studied. The effects of basicity ( r ), Al 3. /SO 4 2. molar ratio and aging time on the electrical conductivity of PACS solution were also investigated. The experimental results show that the degree of polymerization of polyaluminium chloride(PAC) increases when SO 4 2. ion is added. The higher the basicity( r ) and the longer the aging time, the larger the size of polymer PACS. The ability of PACS neutralizing the charge on Kaolinite decreases with the increase of aging time. The electrical conductivity of PACS solution(the concentration of Al 3. ion is 0.18 mol/L) with different aging time is the function of the basicity and Al 3. /SO 4 2. molar ratios and has its maximum at r =0.5 and Al 3. /SO 4 2. =12.

关键词： coagulant PACS morphology transmission electron microscope electrical conductivity coagulation

Density functional study on enantioselective reduction of keto oxime ether with borane catalyzed by oxazaborolidine

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Science China chemistry 2006年第4期49卷 296-307页

作者： LI Ming1, ZHENG Wenxu2.& TIAN Anmin2.1. department of chemistry, Southwest-China Normal {2., Chongqing 400715, China 2. department of chemistry, Sichuan {2., Chengdu 610064, China department of chemistry Southwest-China Normal University Chongqing China department of chemistry Sichuan University Chengdu China

The enantioselective reduction of keto oxime ether with borane catalyzed by oxazaborolidine is discussed by the density functional theory (DFT) method. The main intermediates and transition states for this reaction are optimized completely at the B3.YP/6-3.g(d) level, and the transition states are verified by vibrational modes. As shown, the chirality-controlled steps for this re- action are the hydride transfer from borane to carbonyl carbon and oxime carbon of keto oxime ether, and the chirality for the reduced products is determined in these two reaction steps. In all examined reaction paths, the first hydride is transferred via a six-membered ring and the second hydride via a five-membered ring or a four-membered ring.

关键词： keto oxime ether, oxazaborolidine, enantioselective reduction, DFT.

Electrocatalytic Oxidation of Hypophosphite on Nickel Electrode ──In Situ UV-Vis Spectroscopic study

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Chinese Chemical Letters 1999年第10期10卷 863-866页

作者： Yue ZENG Shao Min ZHOU ( department of chemistry. {2. Normal {3., changsha 410006 State Key Laboratory for Physical chemistry of the Solid Surface.department of chemistry. Xiamen {3., Xiamen 3.1005) department of chemistry Hunan Normal University State Key Laboratory for Physical chemistry of the Solid Surface Department of Chemistry Xiamen University

The electrocatalytic oxidation of hypophosphite on a nickel electrode has been studiedby means of in site UV-Vis subtractive reflectance spectroscopy. An absorbency band around 2.5um . which was ascribed to the formation of an intermediate, PHO2., was observed in theelectrocatalytic oxidation process. Accordingly, the electrocatalytic oxidation of hypophosphitemight undergo a H abstraction of hypophosphite from the P-H bond to form the phosphoruscentred radical PHO2., which is subsequently electrooxidized to the final product, phosphite.

关键词： In situ UV-Vis subtractive reflectance spectroscopy electrooxidation hypophosphite mechanism.

THE LARGEST SOLUTION OF LINEAR EQUATION OVER THE COMPLETE HEYTING ALGEBRA

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Acta Mathematica Scientia 2010年第3期30卷 810-818页

作者：周惊雷李庆国 College of Mathematics and Econometrics Hunan University department of Mathematics Hunan University of Arts and Science

Let （L, 〈, V, A） be a complete Heyting algebra. In this article, the linear system Ax = b over a complete Heyting algebra, where classical addition and multiplication operations are replaced by V and A respectively, is studied. We obtain：（i） the necessary and sufficient conditions for S（A,b）≠Ф; （ii） the necessary conditions for IS（A,b）｜ = 1. We also obtain the vector x ∈ Ln and prove that it is the largest element of S（A, b） if S（A, b）≠Ф.

关键词： Complete lattice Heyting algebra linear system minimal covering