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Cooperative Enhancement of Cost Threshold in the Spatial N-Person Snowdrift Game

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Chinese Physics Letters 2012年第8期29卷 301-304页

作者： LU Dong-Liang zhang hong-bin GE Juan XU Chen School of Computer Science and Technology Soochow UniversitySuzhou 215006 School of Physical Science and Technology Soochow UniversitySuzhou 215006

We study the cooperative behaviour of the N-person snowdrift game on a square lattice with different neighbourhoods and the cost threshold M for the *** apply the imitation mechanism for the players and find that there is an optimal frequency of cooperation fC as M varies in the game and the peak of fC shifts to higher M when more neighbours on the lattice are involved in the *** a given cost-to-benefit ratio r,the system shows discontinuous phase transitions and the behaviour of fC vs M shows step-like *** construct payoff level structures and find that the above features can be understood by analyzing the transition behaviour between the payoff *** variations of r and M are equivalent to tune the payoff level *** plateaus in the step-like structure have similar payoff level structures and the discontinuous jumps correspond to different payoff level structures.

关键词： behaviour discontinuous apply

Scopariusols L–T, nine new ent-kaurane diterpenoids isolated from Isodon scoparius

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Chinese Journal of Natural Medicines 2018年第6期16卷 456-464页

作者： JIANG Hua-Yi LI Xiao-Nian SUN Han-Dong zhang hong-bin PUNO Pema-Tenzin Key Laboratory of Medicinal Chemistry for Natural Resources Ministry of EducationSchool of Chemical Science and TechnologyYunnan UniversityKunming 650091China State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy ofSciencesKunming 650201China University of Chinese Academy of Sciences Beijing 100049China

Nine new ent-kaurane diterpenoids, named scopariusols L–T(1–9), were isolated from the aerial parts of Isodon scoparius. Their structures were characterized mainly by analyzing the NMR and HR-ESI-MS data, and the absolute configuration of 1 was determined by single-crystal X-ray diffraction. Compound 1 was active against five human tumor cell lines(HL-60, SMMC-7721, A-549, MCF-7, and SW-480), and it also inhibited NO production in LPS-stimulated RAW264.7 cells, with an IC50 value of 0.6 μmol·L-1.

关键词： Isodon scoparius Ent-kaurane diterpenoids X-ray diffraction Cytotoxicity Anti-inflammatory activity

The Study on the Noncovalent Complexes of Silver Ion with Xanthone Diglycosides by Electrospray Ionization with Tandem Mass Spectrometry

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Chinese Chemical Letters 2006年第3期17卷 391-394页

作者： Yan Guo SUN Xi zhang hong bin XIAO Xin Miao LIANG Dalian Institute of Chemical Physics Chinese Academy of Science Dalian 116023

The silver ionic complexes of xanthone glycosides were studied by ESI-MS/MS in the positive ion mode. The fragmentation pathways of silver ionic complexes under collisioninduced dissociation （CID） were investigated and the differences in MS/MS spectra of different silver ionic complexes of xanthones were correlated to the characterization of saccharide and the coordination pattern of silver ion with xanthones, including the glycosilation position and linkage type of disaccharide （1-2 and 1-6 linkages）.

关键词： Electrospray ionization MS/MS xanthone glycosides silver ionic complexes

Temperature change along elevation and its effect on the alpine timberline tree growth in the southeast of the Tibetan Plateau

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Advances in Climate Change Research 2018年第3期9卷 185-191页

作者： CHEN Bao-Xiong SUN Yu-Fang zhang hong-bin HAN Zhi-Hua WANG Jing-Sheng LI Yao-Kui YANG Xiao-Lin Rural Energy & Environment Agency Ministry of Agriculture and Rural Affairs of the People's Republic of China Beijing 100125 China National Defense Examination Center Beijing 100082 China Lhasa Plateau Ecosystem Research Station Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Science Beijing 100101China Tibet Agricultural and Animal Husbandry College Linzhi 860000 China

Smith fir （Abies georgei var. smithii）, which is the timberline constructive tree species in the cool slope of Mt. Sygera in the southeast ofTibet, plays a very important role in maintaining the timberline completeness and indicating global climate change. This study uses theinstrumental recorded meteorological data along the altitude from 3600 to 4400 m at every 200 m in the growing season, investigates the smithfir growth biomass from 2006 to 2010 in the same timberline ecotone, and makes a non-linear regression analysis to determine the relationshipbetween the alpine tree growth biomass and its in-situ environment condition. The results showed that the cool and warm slope share different airtemperature lapse rates, which were 0.48 C （100 m）1 in the warm slope and 0.54 C （100 m）1 in the cool slope, respectively. However, thedominant timberline tree species in the warm slope was Sabina saltuaria, and it can reach as high as 4570 m, which is approximately 170 mhigher than that in the cool slope. Moreover, the smith fir in the cool slope was only distributed in the range of elevation from approximately3600 to 4400 m. The altitude of approximately 3800 m was the appropriate altitude for the growing smith fir, where the mean air temperature inthe growing season was about 9.0 C, and the young smith fir tree can form more biomass. The results suggested that alpine forest chose asuitable environment where trees can grow more in the prolonged succession, but not in the warmer or cooler condition, it could be seen as abiological evidence for climate change.

关键词： Abies georgei var. smithii Growth biomass Sabina saltuaria In-situ environment condition Non-linear regression analysis

Preemptive analgesic effects of flurbiprofen axetil in patients undergoing radical resection of esophageal carcinoma via the left thoracic approach

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Chinese Medical Journal 2012年第4期000卷 579-582页

作者： Wang Yan zhang hong-bin Xia bin Wang Gong-ming zhang Meng-yuan Shandong Univ Prov Hosp Dept Anesthesiol Jinan 250021 Shandong Peoples R China Shandong Univ Prov Hosp Dept Cardiac Surg Jinan 250021 Shandong Peoples R China

Background Systemic non-steroidal anti-inflammatory drugs have been evaluated for their possible preemptive analgesic *** efficacy of flurbiprofen axetil for preemptive analgesia in patients undergoing radical resection of esophageal carcinoma via the left thoracic approach needs further *** aim of this study was to research the preemptive analgesic effects of flurbiprofen axetil in thoracic surgery,and the influence of preoperative administration on postoperative respiratory *** This randomized,double-blind,controlled trial enrolled 60 patients undergoing radical resection of esophageal carcinoma via the left thoracic *** management was *** patient was randomly assigned to receive either 100 mg flurbiprofen axetil intravenously 15 minutes before incision （PA group） or intravenous normal saline as a control （C group）.Postoperative analgesia was with sufentanil delivered by patient-controlled analgesia *** sufentanil consumption,visual analog scale pain scores,plasma levels of interleukin-8,and oxygenation index were *** Compared with the preoperative baseline,postoperative patients in the PA group had no obvious increase in pain scores （P 〉0.05）,but patients in the C group had significantly increased pain scores （P〈0.05）.Pain scores in the C group were significantly higher at 24 hours postoperatively than *** comparisons showed lower visual analog scale scores at 2-24 hours postoperatively in the PA group than the C group （P 〈0.05）.Sufentanil consumption and plasma interleukin-8 levels at 2 and 12 hours postoperatively were significantly lower in the PA group than the C group （P 〈0.05）.The oxygenation index at 2 and 12 hours postoperatively was significantly higher in the PA group than the C group （P〈0.05）.Conclusions Intravenous flurbiprofen axetil appears to have a preemptive analgesic effect in patients undergoing radical resection of esophageal carc

关键词： flurbiprofen axetil preemptive analgesia radical resection esophageal carcinoma

Effects of nuclei ambiguus and dorsal motor nuclei of vagus on gastric H^+ and HCO_3^- secretion in rats

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World Journal of Gastroenterology 2006年第20期12卷 3271-3274页

作者： Xue-Ying zhang hong-bin Ai Xi-Yun Cui College of Life Sciences Shandong Normal University Jinan 250014 Shandong Province China

AIM: To determine the effects of electrical stimulation of nucleus ambiguus (NA) and dorsal motor nuclei of vagus (DMV) on gastric acid and bicarbonate secretion in rats. METHODS: NA and DMV in rats were electrically stimulated. Pylorus ligation or esophagus perfusion was used to collect the gastric secretion. The titratable H+ quantum, H+ concentration, HCO3- secretion quantum were measured. RESULTS: Electrical stimulation of NA had no effects on the volume of gastric juice, titratable acidity and acid concentration, but elicited a pronounced increase in the total bicarbonate. However, electrical stimulation of DMV significantly increased the titratable acidity, the volume of gastric juice and the acid concentration. Similarly, electrical stimulation of either NA or DMV decreased the respiratory frequency and sinus bradycardia. CONCLUSION: NA in rats can not control the secretion of gastric acid but the secretion of bicarbonate in gastric juice, while DMV controls the secretion of gastric acid.

关键词： Rat Nucleus ambiguus Dorsal motor nuclei of vagus Gastric acid Gastric bicarbonate

Studies of Catalysis in Partial Oxidation of Methane to Syngas（Ⅱ）──Chemisorbed Species，Energetics and Mechanism

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Chemical Research in Chinese Universities 1995年第4期11卷 323-335页

作者： CHEN Ping zhang hong-bin LIN Guo-dong andTSAI Khi-rui(Department of Chemistry &State Key Laboratory for Physical Chemistyry of the Solid Surface ,Xiamen University ,Xiamen 361005) XIAMEN UNIV DEPT CHEMXIAMEN 361005PEOPLES R CHINA XIAMEN UNIV STATE KEY LAB PHYS CHEM SOLID SURFACEXIAMEN 361005PEOPLES R CHINA

he characteristic study,by means of in-situ IR spectroscopy, of chemisorbed species on the Ni-catalysts for the partial oxidation of methane(POM)to syngas demonstrated the existence of CH_x(a)and H_xCO(a)adspecies on the functioning Ni-catalysts, Several designed experimental investigations on the reactivities of methane with CO_2 and with O_2,respectively,over the Ni-catalysts, and of CO_2 with the prereduced Ni-catalyst,ats well as of the deposited carbon with CO_2 and with O_2,respectlvely,liave been carried out and the reLqults were unfavorable to the two-step mechanistic interpretation proposed for the POM reaction. By means of tlie BOC-MP Approach,energetics of a set of elementary reactions,which may be involved in the POM process,on the clean(111)surface of Ni,Fe,Cu and Pd, re- spectively,has been *** result;of the experiments and the calculation of the present work favor the direct catalytic dissociation-plus-surface oxidation-plus-further debdrogenation mechanism as the dominant pathway making major contribution to the POM reaction.

关键词： Partial oxidation of methane Syngas Chemisorbed species Energetics. Mechanism

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图像水印容量与可靠性

北京工业大学学报 2005年第4期31卷 348-351页

作者：张帆张鸿宾北京工业大学计算机学院北京100022

为了研究图像的水印容量,在满足水印不可感知性的前提下,基于图像的内容自适应地限制水印的嵌入功率,分析了水印容量问题以及水印容量与检测可靠性的关系.研究结果表明,水印检测错误率主要取决于水印的平均能量和水印容量,而且随着水印... 详细信息

为了研究图像的水印容量,在满足水印不可感知性的前提下,基于图像的内容自适应地限制水印的嵌入功率,分析了水印容量问题以及水印容量与检测可靠性的关系.研究结果表明,水印检测错误率主要取决于水印的平均能量和水印容量,而且随着水印容量的提高而增加.

关键词：数字水印水印容量可靠性

Studies on Catalysis in Partial Oxidation of Methane to Syngas(Ⅰ)──Performance and Characterization of Ni-based Catalysts

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Chemical Research in Chinese Universities 1996年第1期12卷 70-80页

作者： CHEN Ping zhang hong-bin LIN Guo-dong and TSAI Khi-rui (Department of Chemistry &. State Key Laboratory for Physical Chemistry of the Solid Surface, Xiamen University, Xiamen, 361005) XIAMEN UNIV DEPT CHEMXIAMEN 361005PEOPLES R CHINA XIAMEN UNIV STATE KEY LAB PHYS CHEM SOLID SURFACEXIAMEN 361005PEOPLES R CHINA

Highly active and selective Ni-based catalysts for partial oxidation of methane (POM) to syngas (CO/H,) have been studied and developed. Spectroscopic characterization by XRD, XPS, EPR, etc. demonstrated that under the POM reaction conditions, the Ni-components of the catalysts investigated were reduced and enriched on the surface to form metallic Ni0-phase. A comparative study of the first series of transition-metals showed that only Ni and Co have a high POM activity and selectivity, whereas the others (including Mn, Fe, Cu, etc. ) give mainly complete combustion products, Co, and H2O. The results favor the following viewpoints: the PoM activity is related with the rapidly changeable valence transitionmetal sites, M0/M2+ (e. g. Ni0/Ni2+ ), on the surface of the functioning catalysts;the transition-metal sites in zero-valence state seem to be responsible for the activation and dehydrogenation of methane by homolytic splitting of its C-H bonds on these sites. and the nature of rapidly changeable valence of the active sties is requisite for activation and rapid conversion of dioxygen.

关键词： Partial oxidation of methane Syngas Ni-based catalysts