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On adjacent-vertex-distinguishing total coloring of graphs

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Science china {1. 2005年第3期48卷 289-299页

作者： ZHANG Zhongfu, CHEN Xiang’en, LI Jingwen, YAO Bing, LU Xinzhong & WANG Jianfang College of mathematics and Information Science, Northwest Normal University,{1.,{2. Department of Computer, lanzhou Normal College,{1.,{2. institute of Applied mathematics, lanzhou Jiaotong University,{1.,{2. College of Information and Electrical Engineering, lanzhou Jiaotong University,{1.,{2. institute of Applied mathematics, Chinese Academy of Sciences, Beijing 1.0080,{2. 1. College of mathematics and Information Science Northwest Normal University 730070 Lanzhou China 2. Department of Computer Lanzhou Normal College 730070 Lanzhou China 3. institute of Applied {1. Lanzhou Jiaotong University 730070 Lanzhou China 4. College of Information and Electrical Engineering Lanzhou Jiaotong University 730070 Lanzhou China 5. institute of Applied {1. Chinese Academy of Sciences 100080 Beijing China

In this paper, we present a new concept of the adjacent-vertex-distinguishing total coloring of graphs (briefly, AVDTC of graphs) and, meanwhile, have obtained the adjacent-vertex-distinguishing total chromatic number... 详细信息

关键词： graph, proper total coloring, adjacent-vertex-distinguishing total coloring, adjacent-vertex-distinguishing total chromatic number.

Two types of changes in apparent resistivity in earthquake prediction

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Science china Earth Sciences 2011年第1期54卷 145-156页

作者： DU XueBin1.2.1.1. institute of Seismology,{2. Earthquake Administration, {1. 730000,{2. 2.0} Base of Earthquake Science institute,{2. Earthquake Administration, {1. 730000,{2. 1. lanzhou {1. of Seismology China Earthquake Administration Lanzhou 730000 China2. Lanzhou Base of Earthquake Science Institute China Earthquake Administration Lanzhou 730000 China

Two types of changes in apparent resistivity (AR) have been linked to earthquake occurrences. This paper studies the changes and their causes, in detail with the ultimate purpose of developing and assessing a method of earthquake (EQ) prediction. The AR changes of the first type (CFT) are considered to be precursors related to earthquakes (EQs); these appear mostly in the medium-term period before EQs and in the short-term period preceding EQs. The changes of the second type (CST) are characterized by a turning anomaly of a long-trend AR variation or the drastically descending/ascending anomaly superimposed on such a variation; these appear synchronously in large areas, such as the Chinese mainland, and northern and northwestern china, ect. Their spatio-temporal clusters correspond well to high seismicities in the areas and distant great EQs around the Chinese mainland. Based on the behaviors of the two types of changes, the AR changes observed prior to the Ms8.0 Wenchuan EQ of {1.08 are studied. The results show that in the medium-term period before the EQ, noticeable anomalies appeared synchronously at four stations around the Songpan-Ganzi active block, but only weak upward changes were observed in the short-term period preceding the EQ, which caused the prediction of the imminent EQ to fail.

关键词： strong earthquake apparent resistivity two types of changes spatio-temporal cluster Wenchuan earthquake

Strengthening of the boreal winter Hadley circulation and its connection with ENSO

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Progress in Natural Science:Materials International 2007年第11期17卷 1327-1333页

作者： Ma Jie1.2.and Li Jianping2.1. College of Atmospheric Sciences, lanzhou University, lanzhou 730000,{2. 2. LASG, institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 1.002.,{2.) College of Atmospheric Sciences Lanzhou University Lanzhou 730000 China LASG Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

Empirical orthogonal function (EOF) analysis is carried out for the year-to-year variability of the boreal winter (DJF) mass stream function of the mean meridional circulation (MMC) during the period 1.48—2.05. The results demonstrate that it is dominated by the equatorially asymmetric and symmetric modes. Further analysis shows that the former mode is linked with the boreal winter Hadley cell mainly on the decadal time-scale, and the latter on the interannual time-scale. The asymmetric mode index (AMI) with a clear upward trend contributes to the decadal strengthening of the boreal Hadley circulation, and is closely correlated with the tropical SST warming, especially in the region of Indo-west Pacific warm pool (INWP). Furthermore, the AMI also contributes to the abrupt change of the correlation coefficient between the boreal Hadley circulation and ENSO after 1.76. The symmetric mode index (SMI) with robust and stable linkage with ENSO shows a significant interannual variability, suggesting that the variability of the Hadley circulation is mainly associated with ENSO on the interannual time-scale.

关键词： the Hadley circulation interannual time-scale decadal time-scale

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 730070,{2. 2. State Key Laboratory of Frozen Soil Engineering, Cold and Arid Regions Environmental and Engineering Research institute, Chinese Academy of Sciences, lanzhou 730000,{2. 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.

Mantle-derived rare-gas releasing features at the Tianchi volcanic area, Changbaishan Mountains

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Chinese Science Bulletin 1997年第9期42卷 768-771页

作者： SHANGGUAN Zhiguan and SUN Mingliang1. institute of Geology, State Seismological Bureau, Beijing 1.00{1., china {1. {{1. institute of Geology, Chinese Academy of Sciences, {{1. 730000, china institute of Geology State Seismological Bureau Beijing China lanzhou {1. of Geology Chinese Academy of Sciences Lanzhou China

TIANCHI volcano,Changbaishan Mountains isthe largest modern active volcano in East *** times strong volcanic erupting activ-ities occurred in the Cenozoic *** vol-canic activities have revived again in the *** investi... 详细信息

关键词： Tianchi volcanic area Changbaishan Mountains mantle-derived rare gas 3He/ 4He 40 Ar/36 Ar 4He/2. Ne 4He/40Ar isotope ratios.

Radiobiological response of human hepatoma and normal liver cells exposed to carbon ions generated by Heavy Ion Research Facility in lanzhou

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Science china(Physics,Mechanics & Astronomy) 2006年第1期49卷 72-76页

作者： YANG Jianshe1.2. LI Wenjian1. JIN Xiaodong1. JING Xigang1. GUO Chuanling1. WEI Wei1.& GAO Qingxiang3 1. {1. of Modern Physics, Chinese Academy of Sciences, lanzhou 730000,{2. 2. Life Science School of North West Normal University, lanzhou 730070,{2. 3. Life Science School of lanzhou University, lanzhou 730000,{2. 1. institute of Modern Physics Chinese Academy of Sciences Lanzhou 730000 China 2. Life Science School of North West Normal University Lanzhou 730070 China 3. Life Science School of lanzhou University Lanzhou 730000 China

Human hepatoma and normal liver cells were irradiated with 1.0}6+ ion beams (LET = 96.05 keV/μm) and γ-rays at Heavy Ion Research Facility in {1. (HIRFL). The chromatid breaks and break types were detected using the premature chromosome con- densation technique. Our experimental results showed that chromatid breaks seem to have a good relation with 1.0}6+ absorbed dose and 1.0}6+ are more effective to induce chromatid breaks as compared to the γ-rays. For 1.0}6+ ion irradiation the major break was isochromatid break, while chromatid breaks were dominant for γ-ray irradiation. We also observed that the Relative Biology Effectiveness (RBE) of 1.0}6+ ion is about 2.5 times higher than that of γ-rays.

关键词： biological response, tumor cell, normal cell, heavy ion HIRFL.

Friction-reducing and antiwear behavior of metal halide-stabilized linear phosphazene derivatives as lubricants for a steel-on-steel contact

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Science china(Technological Sciences) 2005年第3期48卷 282-291页

作者： ZHU Jiamei 1.2., LIU Weimin 2.& LIANG Yongmin 2.1. School of Chemical Engineering and Technology, china University of Mining and Technology, Xuzhou 2.1.08, china 2. State Key Laboratory of Solid Lubrication, {2. institute of Chemical Physics, Chinese Academy of Sciences, {2. 730000, china 1. School of Chemical Engineering and Technology China University of Mining and Technology 221008 Xuzhou China 2. State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical Physics Chinese Academy of Sciences 730000 Lanzhou China

A series of novel metal halide-stabilized linear phosphazene derivatives were synthesized. The friction-reducing and antiwear abilities of the resulting products as the lubricants for a steel-on-steel contact were comparatively investigated on an Optimol SRV oscillating friction and wear tester. The morphology of the worn steel surface was observed on a scanning electron microscope, while the chemical states of some typical elements on the worn steel surface were examined by means of X-ray photoelectron spectroscopy. It was found that both the side branch structures and central metals influenced the friction-reducing and antiwear behaviors of the synthetic derivatives as the lubricants, which was related to the different adsorption activities of the organic compounds composed of different organic ingredients and metallic ions on a nascent metal surface. All the synthetic lubricants except for the iron (III) derivative showed increased antiwear abilities with increasing metallic ionic radius. A protective layer originated from the tribochemical reaction together with the adsorbed boundary lubricating layer containing organic fluorine compounds, nitrogen oxide, and Fe 3 (PO 4 ) 2.plays an important role in improving the friction and wear behavior of the steel-on-steel system.

关键词： metal halide-stabilized linear phosphazene derivatives,lubricant,steel,tribological properties.

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. {1. of mathematics, Shaanxi Normal University, Xi’an 71.062.{2. 2. School of Sciences, lanzhou University of Technology, lanzhou 730050,{2. 3. Research Center for Science, Xi’an Jiaotong University, Xi’an 71.049,{2. 1. institute of {1. 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.

Pollen records of Holocene vegetation and climate changes in the Longzhong Basin of the Chinese Loess Plateau

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Progress in Natural Science:Materials International 2007年第12期17卷 1445-1456页

作者： Tang Lingyu1.and An Chengbang2.1. Nanjing {1. of Geology and Paleontology, Chinese Academy of Sciences, Nanjing 2.0008, china 2. Key Laboratory of Western china’s Environment Systems, MOE, lanzhou University, lanzhou 730000, china) Nanjing institute of Geology and Paleontology Chinese Academy of Sciences Nanjing 210008 China Key Laboratory of Western china’s Environment Systems MOE Lanzhou University Lanzhou 730000 China

Pollen records with an average time resolution of 2.-2.0 years from Holocene loess sections at Dingxi, Qin'an, and other localities of Gansu Province reveal a detailed history of vegetation and climate changes in the western Loess Plateau. For most time of the Holocene, the landscape was dominated by grasslands or forest steppes. However, during the middle Holocene (7.5-5.8 ka BP), relatively dense forests developed, and the endemic vegetation flourished, suggesting a much warmer and more humid climate condition than the present. Superimposed upon this general pattern are several dry intervals marked by the episodic expansion of grasslands or forest steppe. Xeric vegetation expanded after 3.8 ka BP, indicating a trend towards dry conditions.

关键词： pollen records glasslands coniferous forests Holocene Loess Plateau.