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A note on n-edge chromatic number

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Chinese Science Bulletin 1997年第23期42卷 1952-1954页

作者： SUN Liang and ZHANG Zhongfu1. Department of applied mathematics, Beijing {2. of Technology, Beijing 100081, China 2. institute of applied mathematics, lanzhou {2. of Railway, lanzhou 73.070, China Department of applied mathematics Beijing Institute of Technology Beijing 100081 China

ALL graphs appearing in this note are simple. A graph with p vertices and q edges will becalled a (p, q )-graph. The maximum degree of G is denoted by Δ(G).Let n≥2.be an integer. The n-edge chromatic number X_n (G) of a simple graph G is theminimum cardinality of a set of colors with which one can assign the colors to the edges of Gsuch that the edges on a path of length less than or equal to n receive different *** aim of this note is to explore the bounds for X’_n (G) and X’_n (G) + X’_n (G). It is

关键词： graph complement n-edge chromatic number.

D(β)-vertex-distinguishing total coloring of graphs

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Science China mathematics 2006年第10期49卷 1430-1440页

作者： ZHANG Zhongfu,LI Jingwen,CHEN Xiang’en,YAO Bing, WANG Wenjie & QIU Pengxiang institute of applied Mathematic,{2., lanzhou 73.070, China College of mathematics and Information Science, Northwest Normal university, lanzhou 73.070, China College of Information and Electrical Engineering,{2., lanzhou 73.070, China institute of applied Mathematic Lanzhou Jiaotong University Lanzhou 730070 China College of mathematics Information Science Northwest Normal University Lanzhou 730070 China College of Information Electrical Engineering Lanzhou Jiaotong University Lanzhou 730070 China

A new concept of the D(β)-vertex-distinguishing total coloring of graphs, i.e., the proper total coloring such that any two vertices whose distance is not larger than β have different color sets, where the color set of a vertex is the set composed of all colors of the vertex and the edges incident to it, is proposed in this paper. The D(2.-vertex-distinguishing total colorings of some special graphs are discussed, meanwhile, a conjecture and an open problem are presented.

关键词： graph, total coloring, D(β)-vertex-distinguishing total coloring, D(β)-vertexdistinguishing total chromatic number.

A computer simulation of nucleation and growth of thin films

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Science China(Physics,Mechanics & Astronomy) 2004年第4期47卷 442-451页

作者： ZHENG Xiaoping1,ZHANG Peifeng2.HE Deyan2.LIU Jun2. MA Jiantai3 1. Key Laboratory of Opto-Electronic Technology and Intelligent Control, Ministry of Education, lanzhou jiaotong university, lanzhou 73.070, China 2. School of Physical Science and Technology, {2. university, {2. 730000, China 3. School of Chemistry and Chemistry Engineering, {2. university, {2. 730000, China 1. Key Laboratory of Opto-Electronic Technology and Intelligent Control Ministry of Education Lanzhou Jiaotong University 730070 Lanzhou China 2. School of Physical Science and Technology Lanzhou University 730000 Lanzhou China 3. School of Chemistry and Chemistry Engineering Lanzhou University 730000 Lanzhou China

A three-dimensional kinetic Monte Carlo technique has been developed for simulating the nucleation and growth of thin films. This model involves incident atom attachment, surface diffusion of the atoms on the growing surface and atom detachment from the growing surface. It takes some new effects into account, such as a significant improvement in calculation of activation energy for the atom diffusion, which renders the model more reasonable. In addition three optimum temperatures and the consistency of their dependence on deposition rate have been found out; the dependence of the surface roughness and relative density on the deposition rate has been discussed; and the approximation of freezing neighbour atoms and periodic boundary conditions has been applied.

关键词： Monte Carlo, thin film, nucleation, surface roughness, relative density.

Theory of truth degrees of propositions in the logic system Ln^＊

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Science in China(Series F) 2006年第4期49卷 471-483页

作者： LI Jun1,2.& WANG Guojun1,3 1. institute of mathematics, Shaanxi Normal {2., Xi’an 710062. China 2. School of Sciences, lanzhou {2. of Technology, lanzhou 730050, China 3. Research Center for Science, Xi’an jiaotong {2., Xi’an 710049, China 1. institute of mathematics Shaanxi Normal University Xi’an 710062 China 2. School of Sciences Lanzhou University of Technology Lanzhou 730050 China 3. Research Center for Science Xi’an Jiaotong University Xi’an 710049 China

By means of infinite product of uniformly distributed probability spaces of cardinal n the concept of truth degrees of propositions in the n-valued generalized Lu- kasiewicz propositional logic system Ln^＊ is introduced in the present paper. It is proved that the set consisting of truth degrees of all formulas is dense in [0,1], and a general expres- sion of truth degrees of formulas as well as a deduction rule of truth degrees is then obtained. Moreover, similarity degrees among formulas are proposed and a pseudo-metric is defined therefrom on the set of formulas, and hence a possible framework suitable for developing approximate reasoning theory in n-valued generalized Lukasiewicz propositional logic is established.

关键词： truth degree similarity degree approximate reasoning.

Three Novel Eremophilanolides from Ligularia virgaurea ***

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Chinese Chemical Letters 2004年第12期15卷 1441-1444页

作者： Quan Xiang WU Yan Ping SHI Li YANG State Key Laboratory of applied Organic Chemistry, lanzhou {2., lanzhou 730000 lanzhou institute of Chemical Physics Chinese Academy of Sciences (CAS) lanzhou 730000 State Key Laboratory of applied Organic Chemistry Lanzhou University lanzhou institute of Chemical Physics Chinese Academy of Sciences (CAS)

From the alcoholic extract of the whole plant of Ligularia virgaurea spp. oligocephala,three novel eremophilane sesquiterpene lactones, 6α, 10α-dihydroxy-1-oxoeremophila- 7(11),8(9)-dien-8, 12.olide, 6β, 10α-dihydroxy-1-oxoeremophila-7 (11), 8 (9)-dien-8, 12.olide and10α-diydroxy-1-oxoeremophila-7(11), 8 (9)-dien-8, 12.olide were isolated. Their structure s wereelucidated by various, spectroscopic methods including intensive 2. NMR techniques (COSY,HMQC, HMBC and ~1H-~1H NOESY) and HR-MS.

关键词： Ligularia virgaurea spp oligocephala Compositae sesquiterpene lactones eremophilanolides.

Multifield coupling model and its applications for pile foundation in permafrost

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Science China Earth Sciences 2005年第7期48卷 968-977页

作者： WU Yaping1,2. ZHU Yuanlin2. GUO Chunxiang1, SU Qiang1 & MA Wei2.1. School of Civil Engineering, lanzhou jiaotong university, lanzhou 73.070, China 2. State Key Laboratory of Frozen Soil Engineering, Cold and Arid Regions Environmental and Engineering Research {2., Chinese Academy of Sciences, lanzhou 730000, China School of Civil Engineering Lanzhou Jiaotong University Lanzhou 730070 China State Key Laboratory of Frozen Soil Engineering Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China

Importing the interface element which links the frozen soil base with concrete piles and considering the couplings of stress field, temperature field and moisture field, this paper es- tablishes the nonlinear visco-elastic plastic finite element model of pile-soil. For a practical bridge structure the stress field and displacement field of single pile in freezing process are calculated. This paper emphatically studies the process of the tangential frost heave stress field, freezing stress field and displacement field varying with time, and ulteriorly studies time variation process of single pile carrying capacity in freezing process.

关键词： permafrost pile foundation freezing process multifield coupling analysis model.

Improvements on radiation-hardened performance of static induction transistor

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Science China(Information Sciences) 2010年第5期53卷 1089-1096页

作者： WANG YongShun 1 , LUO XianLiang 1 , LI HaiRong 2., WANG ZiTing 1 , WU Rong 1 , ZHANG CaiZhen 2.& LI SiYuan 2.1 School of Electronic and Information Engineering, lanzhou jiaotong university, lanzhou 73.070, China 2.{2. of Microelectronics, School of Physical Science and Technology, lanzhou university, lanzhou 730000, China 1. School of Electronic and Information Engineering Lanzhou Jiaotong University Lanzhou 730070 China2. Institute of Microelectronics School of Physical Science and Technology Lanzhou University Lanzhou 730000 China

The radiation-hardened performances of static induction transistor (SIT) have been studied in depth in this paper. The effects of radiation of electron beam on the I-V characteristics, carrier distribution and potential distribution in the channel of SIT have been represented. A large number of electron-hole pairs are generated in the depletion region of reversely biased gate-channel PN junction. The radiation-generated electrons drift towards the drain region at high positive potential, while generated holes flow into gate region biased to the lowest potential. With the accumulation of holes in gate region, the gate potential is boosted, resulting in a decrease in the height of potential barrier in channel, and an increase in drain current. I-V characteristics of SIT in the presence of radiation have been theoretically derived, and compared with experimental results. With the increase in thickness of epitaxial layer, the radiation-hardened capability of SIT is continuously improved until the optimum thickness of 2. μm is reached. The optimum matching relationship among geometric, material and technological parameters has been represented to acquire excellent radiation-hardened performances of SIT.

关键词： static induction transistor radiation-resistant potential barrier electron beam radiationgenerated carriers

Regioselective Addition of Silyl Enolates to α, β-Unsaturated Aldehyde and its Acetal Catalyzed by MgI2.Etherate

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Chinese Chemical Letters 2003年第8期14卷 800-803页

作者： Xing Xian ZHANG, Wei Dong Z. LI* National Laboratory of applied Organic Chemistry & institute of Organic Chemistry, {2. university, {2. 730000 National Laboatory of applied Organic Chemistry & institute of Organic Chemistry Lanzhou University Lanzhou 730000

Regioselective addition reactions of silyl enolates to a, b-unsaturated aldehyde and its acetal catalyzed by MgI2.etherate give aldol adducts (1, 2.addition) preferentially over Michael adducts (1, 4-addition). This unique regioselectivity is distinctly different with other Lewis acidic promoters and may be attributed to the high oxyphilicity of IMg+.

关键词： MgI2.etherate silyl enolate addition regioselective.

Two Quinones from the Aerial Parts of Sphallerocarpus gracillis

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Chinese Chemical Letters 1999年第11期10卷 919-920页

作者： Neng Yu CHEN Jun SHI Tao CHEN(institute of Organic Chemistry, State Key Laboratory of applied Organic Chemistry,{2. university, {2. 730000) lanzhou Univ Inst Organ Chem State Key Lab Appl Organ Chem Lanzhou 730000 Peoples R China

Two new quinones were isolated from the aerial parts of Sphallerocarpus gracillis. Their structure were determined by spectroscopic methods (HRMS.2. NMR) and finally confirmed by X-ray crystallography.

关键词： quinones Sphallerocarpus gracillis