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Science China Chemistry 2007年第5期50卷 638-642页

作者： YAN Dan1,2,3, JIN Cheng1, XIAO XiaoHe1 & DONG XiaoPing2 1 institute of Chinese Medicine, 302 Hospital of People’s Liberation Army, Beijing 100039, China 2 chengdu University of Traditional Chinese Medicine, chengdu 610075, China 3 Chongqing institute of Technology, Chongqing 400050, China institute of Chinese Medicine 302 Hospital of People’s Liberation Army Beijing China chengdu University of Traditional Chinese Medicine Chengdu China Chongqing institute of Technology Chongqing China

The inhibitory effects of five berberines alkaloids (BAs) from rhizoma ofCoptis chinensis Franch,a traditional Chinese medicinal (TCM) herb,on Bacillus shigae(***)growth were investigated by *** power-time curves of *** with and without BAswere acquired;meanwhile,the extent and duration of inhibitory effects on the metabolism wereevaluated by growth rate constants (k1,k2),half inhibitory ratio (IC50),maximum heat output(P_(max)),and peak time (t_p).The values of k1 and k2 of a shigae in the presence of the five BAsdecreased with the increasing concentrations of ***,P_(max) was reduced,and the value oft_p increased with increasing concentrations of the five *** inhibitory activity varied withdifferent ***50 of the five BAs was respectively 75 mu g/mL for berberine,90 ng/mL forcoptisine,115 mu g/mL for palmatine,220 mu g/mL for epiberberine,and 400 mu g/mL *** sequence of antimicrobial activity of the five BAs:berberine > coptisine >palmatine > epiberberine > *** functional groups methylenedioxy at C2 and C3 on phenylring improve antimicrobial activity more strongly than methoxyl at C2 and C3 on ***,the effect of bacteriostasis is not significant with methylenedioxy or methoxyl at C9and C10 on phenyl ring.

关键词： berberines alkaloids, microcalorimetry, Bacillus shigae, inhibitory effect

GLOBAL STRUCTURE OF A KIND OF PREDATOR-PREY SYSTEM

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Applied Mathematics and Mechanics(English Edition) 1988年第10期9卷 999-1003页

作者：丁孙荭 institute of Mathematical Sciences Chengdu Branch Academia Sinica Chengdu

In this paper we prove a theorem, theorem 2, on nonexistence of closed trajectory for a general predator-prey system. Then, using this theorem and another theorem on existence and uniqueness of limit cycle for predator-prey system, we complete the investigation of a concrete model of predator-prey system (?)=γx(1-x/K)-yx~n/(a+x~2) (?)=y(μx~n/(a+x~2)-D)(n=1,2)under the conditions of all kinds of parameters.

关键词： In GLOBAL STRUCTURE OF A KIND OF PREDATOR-PREY SYSTEM cycle

Permian/Triassic Boundary and Its Correlation in the Daxian-Xuanhan Area, Northeastern Sichuan Province, China

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Acta Geologica Sinica(English Edition) 2008年第1期82卷 56-62页

作者： MA Yongsheng MOU Chuanlong TAN Qinyin YU Qian WANG Ruihua Southern Exploration ＆ Development Company SINOPEC Kunming Yunnan 650200 chengdu institute of Geology and Mineral Resources Chengdu Sichuan 610082

There are different opinions about the Permian/Triassic boundary and its correlation in the Daxian-Xuanhan area because of lacking typical lithological symbols and fossil criterions. Especially, it is very hard to determine the Permian/Triassic boundary in the Daxian-Xuanhan buried areas. This brings many difficulties to geological research and oil and gas exploration. Based on field investigation and studies of well cores, newly found fossils, lithological characteristics and well log analyses, the authors discussed the Permian/Triassic boundary in the Daxian-Xuanhan area and brought forward a specific scheme for its determination and regional correlation.

关键词： Permian/Triassic boundary correlation Daxian-Xuanhan area

How Government Policy Is Implemented in the Private University:A Case Study from China

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Frontiers of Education in China 2018年第3期13卷 426-447页

作者： LIU Xu institute of Fashion and Art design Sichuan Normal UniversityChengdu 610010China institute of Education University College LondonLondon WC1H 0ALEngland

This article is based on original research into institutional governance in private *** provides an in-depth qualitative study of how the private university in China has responded in practice to government *** analysis focuses on three dimensions:the roles of the university council,the president,and the university *** study adopted two methods of data collection:31 separate semi-structured interviews with 21 informants as well as extensive documentary *** revealed that while external policies provide an impetus for change for each university,how key actors in institutional governance understand these policies has a significant effect on how the policies are *** can result in change that can be viewed as either symbolic alteration or as operational *** study provides insights from an empirical investigation by way of a case study on private university governance in China,and also a referential perspective on the governance of private universities in general for policy makers,senior managers,and academics.

关键词： policy implementation accountability governance China

Microcalorimetric investigation of the effect of berberine alkaloids from Coptis chinensis Franch on Staphylococcus aureus growth

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Science China Chemistry 2008年第7期51卷 640-645页

作者： YAN Dan XIAO XiaoHe JIN Cheng DONG XiaoPing institute of Chinese Medicine 302 Hospital of People’s Liberation ArmyBeijing 100039China chengdu University of Traditional Chinese Medicine Chengdu 610075China

The inhibitory effects of three berberine alkaloids (BAs) from rhizome of Coptis chinensis Franch, a traditional Chinese medicinal (TCM) herb, on Staphylococcus aureus growth were investigated by mi- crocalorimetry. The power–time curves of S. aureus with and without BAs were acquired; meanwhile the extent and duration of inhibitory effects on the metabolism were evaluated by studying the growth rate constant (k), half inhibitory ratio (IC50), maximum heat-output power (Pmax), peak time of maximum heat-output power (tp) and total heat production (Qt). The value of k of S. aureus in the presence of the three BAs decreased with the increasing concentrations of BAs. Moreover, Pmax was reduced and the value of tp increased with increasing concentrations of the three drugs. The inhibitory activity varied with different drugs. The values of IC50 of the three BAs are respectively, 101.4 μg/mL for berberine, 241.0 μg/mL for palmatine and 792.3 μg/mL for jateorrhizine. The sequence of antimicrobial activity of the three BAs is: berberine > palmatine > jateorrhizine. It is suggested that the functional group me- thylenedioxy or methoxyl at C2 on the phenyl ring could possibly improve antimicrobial activity more strongly than hydroxyl at C2 on the phenyl ring.

关键词： berberine alkaloid microcalorimetry Staphylococcus aureus inhibitory effect

Anti-seismic research on nuclear engineering siting

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Global Geology 2006年第2期9卷 224-226页

作者： Li CHEN Lei NIE Jijiang LI Delong WANG Xiangyu REN College of Construction Engineering Jilin University Changchun 130026 China Bureau of Environment Ministry of Land and Resources Beijing 100081 China Liaoning Department of Land and Resources shenyang 110032 China institute of Northeast hydroelectric investigation design Changchun 130062 China

Nuclear engineering belongs to significant project;there is higher requirement on *** study has discussed basic factors of selecting sites,anti-seismic research on sitings including the seismic ground motion,probability methods of seismic hazard analysis as well as interaction about structure and foundation,meanwhile provide the reason for nuclear engineering selecting sites.

关键词： nuclear engineering anti-seismic research siting

Visualization analysis of rainfall-induced landslides hazards based on remote sensing and geographic information system-an overview

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International Journal of Digital Earth 2023年第1期16卷 2374-2402页

作者： Zhengli Yang Heng Lu Zhijie Zhang Chao Liu Ruihua Nie Wanchang Zhang Gang Fan Chen Chen Lei Ma Xiaoai Dai Min Zhang Donghui Zhang State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan UniversityChengduPeople’s Republic of China College of Hydraulic and hydroelectric Engineering Sichuan UniversityChengduPeople’s Republic of China School of Geography Development&EnvironmentUniversity of ArizonaTucsonAZUSA Key Laboratory of Digital Earth Science Aerospace Information Research InstituteChinese Academy of SciencesBeijingPeople’s Republic of China School of Geography and Ocean Science Nanjing UniversityNanjingPeople’s Republic of China College of Earth Science Chengdu University of TechnologyChengduPeople’s Republic of China School of Environmental and Geographical Sciences Shanghai Normal UniversityShanghaiPeople’s Republic of China

In recent years,RS and GIS technologies have played an increasingly important role in various aspects of rainfall induced landslide *** order to systematically understand their application situation,this paper extensively used various visualization analysis technologies for in-depth analysis of 1,161 documents collected by the WOS data platform in the past 27 years by combining quantitative and qualitative ***,this article focuses on sub domain analysis from four aspects:landslide detection and monitoring,prediction models,sensitivity mapping,and risk *** study found that the number of literature in thisfield has steadily increased and is expected to continue to *** literature review has attracted widespread attention from the academic community,but it challenging to meet research *** and effective cooperationis between countries,institutions,and authors is very beneficial for promoting progress in *** future development direction is a new intelligent hybrid model that integrates multiple research *** study can provide researchers in thisfield with the core research force,hot topic evolution,and future development trends of future rainfall-induced landslides and contribute to landslide prevention and control decision-making and achieving the United Nations’sustainable development goals.

关键词： Landslide rainfall-induced detection and monitoring predictive model sensitivity mapping risk assessment visual analysis

Sequence Stratigraphy of the Lower Cretaceous Uraniferous Measures and Mineralization of the Sandstone-hosted Tamusu Large Uranium Deposit,North China

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Acta Geologica Sinica(English Edition) 2022年第1期96卷 167-192页

作者： LIU Bo SHI Zhiqiang PENG Yunbiao ZHANG Pengfei LI Peng institute of Sedimentary Geology Chengdu University of TechnologyChengdu 610059China Geologic Party No.208 China Nuclear GeologyBaotouInner Mongolia 014010China

The Bayingobi basin is the Mesozoic-Cenozoic basin in North China in which the Tamusu uranium deposit is *** ore-target layer of the deposit is the Lower Cretaceous Bayingobi Formation,which developed as a fan deltashallow lacustrine *** distributary channel sand body of the fan delta plain and the underwater distributary channel sand body of the fan delta front formed a favorable uranium reservoir,so the study of sequence stratigraphy is extremely important to understanding the genesis of uranium *** the basis of field investigation and a large number of borehole logs,the high resolution sequence stratigraphy of the Lower Cretaceous is divided and the system tracts of different periods are *** relationship between deposition,interlayer oxidation and uranium enrichment is *** Lower Cretaceous Bayingobi Formation can be divided into two fourth-order sequences(Sq1 and Sq2).The lower member of the Bayingobi Formation is referred to as Sq1,which is composed of a falling-stage system tract(FSST)on *** the other hand,the upper member of the Bayingobi Formation is referred to as Sq2,which is composed of a lowstand system tract(LST),transgressive system tract(TST)and highstand system tract(HST).The lowstand system tract forms a favorable stratigraphic structure(mud-sand-mud formation)with the lacustrine mudstone of the overlying transgressive system tract,that is conducive for the migration of uranium-bearing oxygen *** organic matter and pyrite in the fan delta sand body,as well as the dark mudstone in the distributary bay,provided a reducing medium for uranium *** ore body mainly occurs in the distributary channel,underwater distributary channel or the mouth bar of the fan *** a result of the moderate thickness,high permeability,favorable barrier and rich reducing medium,the rich ore body mainly occurs in the underwater distributary channel and mouth bar sand body of the delta *** on study

关键词： Bayingobi Formation sequence stratigraphy fan delta uranium mineralization Tamusu uranium deposit

^(137)Cs Finger Printing Technique for Erosion and Sedimentation Studies

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Journal of Mountain Science 2012年第1期9卷 34-40页

作者： LONG Yi ZHANG Xinbao WEN Anbang HE Xiubin institute of Mountain Hazards and Environment CASChengdu610041China Key Laboratory of Mountain Environment Change and Regulation Chengdu610041China State Key Laboratory of Environmental Geochemistry Institute of GeochemistryCASGuiyang 550002China

137 Cs is an artificial radionuclide with a half-life of 30.2 years,which was released into the environment as a byproduct of atmospheric testing of nuclear weapons during the period of 1950s to 1970s with a peak deposition in 1963.137 Cs fallout was strongly and rapidly adsorbed by soil particles when it deposited on the ground mostly with *** following movements will associate with the adsorbed particles.137 Cs tracing technique has been widely used in soil erosion and sedimentation studies since *** paper introduces the basis of the technique and shows several case studies of assessment of soil erosion rates,investigation of sediment sources and dating of reservoir deposits by using the technique in the Loess Plateau and the Upper Yangtze River Basin.

关键词： 137 Cs soil and sedimentation the Loess Plateau the Upper Yangtze River Basin

Exhaust emission inventory of typical construction machinery and its contribution to atmospheric pollutants in chengdu, China

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Journal of Environmental Sciences 2023年第3期125卷 761-773页

作者： Wubo Fan Wenju Jiang Junhui Chen Fumo Yang Jun Qian Hong Ye institute of New Energy and Low-Carbon Technology Sichuan University(Wangjiang Campus)Chengdu 610207China Sichuan Academy of Environmental Sciences Chengdu 610041China Tsinghua University Beijing 100084China

To study the emission characteristics of typical construction machinery in chengdu,12 construction machinery (excavators,bulldozers,loaders,and forklifts) under idling mode,moving mode,and working mode,were tested using a portable emission measurement system(PEMS).Under three operating modes,the typical construction machinery in the working mode was higher in the fuel-based average emission factors of PM_(2.5)and NOx,while the fuel-based average emission factors of HC and CO were higher in idling *** the results of investigation on ownership and activity levels of construction machinery,an exhaust emission inventory of typical construction machinery of chengdu in 2018 was established according to the recommendation *** annual emission of PM_(2.5),NOx,HC,and CO were 1.67×106,1.61×108,3.83×106,and 1.26×107kg,respectively,and the excavator contributed the maximum emissions,accounting for an average proportion of 43.95%.The emission of construction machinery in chengdu exhibited a clear monthly trend,with the highest from April to October and the lowest from November to *** addition,the exhaust emissions presented an obvious spot-like characteristics,and the high-value areas were mainly concentrated in the surrounding suburban counties such as Shuangliu Wenjiang *** reduce pollution from construction machinery and improve the quality of the atmospheric environment,more effective measures on housing construction and municipal construction should be taken in those districts in chengdu.

关键词： Construction equipment PEMS Emission factor Emission inventory Contribution chengdu