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同济大学学报（自然科学版） 2001年第12期29卷 1503-1506页

作者：宋小欣西南交通大学机械工程学院四川成都610031

变速箱中齿轮传动过程通常分为单齿对啮合区和双齿对啮合区 .为了详细研究这一齿轮传动动力学过程 ,在给出双齿对啮合动力学方程的同时 ,引入了时间系数并制定了算法使其离散化。

关键词：动力学分析啮合数字仿真变速箱齿轮铁道机车

Surfactant-Enhanced Phytoremediation of Soils Contaminated with Hydrophobic Organic Contaminants:Potential and Assessment

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Pedosphere 2007年第4期17卷 409-418页

作者： GAO Yan-Zheng LING Wan-Ting ZHU Li-Zhong ZHAO Bao-Wei ZHENG Qing-Song College of Resource and environmental sciences Nanjing Agricultural University Nanjing 210095 College of environmental and Resource sciences Zhejiang University Hangzhou 310028 （China） school of environmental and Municipal engineering Lanzhou Jiaotong University Lanzhou 730070 （China）

Phytoremediation is becoming a cost-effective technology for the in-situ clean up of sites polluted with hydrophobic organic contaminants （HOCs）. The major factors limiting phytoremediation are the mass transfer, rate of plant uptake, and microbial biodegradation of HOCs. This article discusses the potential of surfactants to enhance desorption, plant uptake, and biodegradation of HOCs in the contaminated sites. Positive effects of surfactants on phytoremediation have been recently observed in greenhouse studies. The presence of some nonionic surfactants including polyoxyethylene sorbltan monooleate （Tween 80） and polyoxyethylene（23.dodecanol （Brij3.） at relatively low concentrations resulted in significant positive effects on phytoremediation for pyrene-contaminated soil. However, the anionic surfactant （sodium dodecyl sulfate, SDS） and the cationic surfactant （cetyltrimethylammonium bromide, CTMAB） were not useful because of their phytotoxicity or low efficiency for surfactant-enhanced phytoremediation （SEPR）. The mechanisms of SEPR for HOC-contaminated sites were evaluated by considering experimental observations. In view of concerns about the cost effectiveness and toxicity of surfactants to plants, more research is needed to enhance the use of SEPR technology.

关键词： hydrophobic organic contaminant remediation SEPR soil surfaztant

New Eremophilane Derivatives From Senecio dianthus

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New Eremophilane Derivatives From Senecio dianthus

A New Secure Password Authentication Scheme Using Smart Cards

中国化学会第9届天然有机化学学术会议

作者： Shuai Huang,Jing Huang,Hui Li,Xiao-li Zhou,Xian-li Zhou~* school of Life science and engineering,{3.,chengdu 61003.,sichuan,.china.

＜正＞Senecio dianthus *** to the Asteraceae family,is herbaceous plant that is widely distributed in china,mostly distributed in Tibet and reputed for reducing fever and detoxification in Tibetan herbal *** chemical components had been investigated by Yan-Hui Li ***,which led to the identification of seven eremophilenolides and eremophilenolide *** this paper,five new eremophilane glucosides（1-5） and one new eremophilane（6）（Figure 1）,together with sixteen known compounds were isolated from this

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Wuhan university Journal of Natural sciences 2008年第6期13卷 739-743页

作者： WANG Bangju1,2, WANG Yuhua3. ZHANG Huanguo1 1. school of Computer, Wuhan university/Key Laboratory of Aerospace Information Security and Trust Computing of Ministry of Education, Wuhan 43.072, Hubei, china 2. school of science, Huazhong Agricultural university, Wuhan 43.070, Hubei, china 3. College of Information science and engineering, Henan university of Technology Zhengzhou 450001, Henan, china school of Information science and Technology Southwest Jiaotong University Chengdu 610031 Sichuan China

Thirteen security requirements for an ideal password authentication scheme using smart cards are listed and a new smart card based password authentication scheme with identity anonymity is proposed. The new scheme can satisfy all the listed ideal security requirements and has the following merits：（1） it can resist all the attacks listed in introduction; （2） less storage memory requirement due to no verification table stored in server; （3. low computational cost due to hash functions based operations; （4） even if the smart card is lost, the new system is still secure; （5） As user identity is anonymous, this scheme is more practical. The new proposed scheme can be applied in source constraint networks.

关键词： password password authentication hash function attack smart card

Two Algorithm Contrast on Temperature Drift in Metal Tube Rotameter

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Two Algorithm Contrast on Temperature Drift in Metal Tube Ro...

Disequilibrium　Analysis　of　Money　Market　in　china

第二届21世纪和谐核电系统国际会议（ISSNP2008）

作者： Ning Jing~1,Peng Jie-gang~2 1.school of Mechanical Eng,southwest jiaotong university,chengdu {3. 61003.,PR china 2.school of Automation,university of Electronic science and Technology of china,chengdu,{3. 610054,PR china

A temperature compensation algorithm was researched based on BP neural network in metal tube *** effect of temperature interference on sense organ(hall organ) of Metal Tube Rotameter was *** temperature drift on hall metal tube rotameter was investigated in thermotank by *** fitting and BP neural network was proposed based on *** results of the two methods were *** last,an off-line training method based on virtual instrument has been put forward.

关键词： Hall Element Temperature Drift Polynomial Fitting BP Neural Network

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Journal of Modern Transportation 1996年第2期13卷 81-87页

作者： Wang Chengzhang Jia Zhiyong Zhao Xinghai school of Economics and Management,southwest jiaotong university,chengdu 61003.,{3. school of Econmics and Management Southwest Jiaotong University Chengdu 610031 China

By the disequilibrium economic theory,this paper first investigates the disequilibrium mathematical economic model of the money market in ***,we study the ... 详细信息

By the disequilibrium economic theory,this paper first investigates the disequilibrium mathematical economic model of the money market in ***,we study the disequilibrium transition of Chinese money market from 1954 to 1993. using a non parametric local fitting *** assuming explicit functional forms,the method of locally weighted maximum likelihood is applied to estimate and test the variations in demand and supply during the period between 1954 to ***,the disequilibrium state and mechanism of Chinese money market are inspected and the direction,the strength and the fluctuation of the disequilibrium are discussed *** the policy suggestions are given about adjusting effectively money demand and supply under the condition of co existing of plan and market *** this paper,a brief review on the disequilibrium researches on money market in foreign countries is also given.

关键词： disequilibrium transition locally weighted optimization Chinese economy money market.

The application of geographic information technology to coastal geomorphology

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Acta Oceanologica Sinica 2009年第5期28卷 49-57页

作者： GUO Wei LI Shuheng ZHU Dakui school of Human Settlements and Civil engineering Xi＇an Jiaotong University Xi＇an 710049 China Department of Computer sciences Xi＇an Jiaotong University Xi＇an 710049 China Department of Urban and Resources sciences Northwest University Xi＇an 710032 China Faculty of environmental sciences University of Waterloo Waterloo N2L3G1 Canada Key Laboratory of Coast ＆ Island Development of Ministry of Education Nanjing University Nanjing 210093 China

With the development of modern oceanic observation technologies, coastal survey data have been experiencing a substantial growth. The integration management of the data from different disciplines, different sources and different formats has become a major research field in coastal geomorphology by using Geographic Information System （GIS）. This paper puts forward a new methodology framework of GIS techniques in coastal ocean geomorphology, including data acquisition, process, analysis, and representation. It focuses on some major GIS techniques to study the land-ocean interaction mechanism, such as spatial analysis, submarine topography model and three-dimension （3.） visualization, and apply its result to coastal urban planning, harbor site selection and geomorphology environment about coral reef and islands on the continental shelf. The case studies cover the whole coastal ocean to serve the social community, economical development and diplomatic rights for decision-making all round in the coastal zone. The research shows clearly that the application of coastal multi-source geospatial platform has changed the traditional coastal geomorphology science dramatically from its research scope, fields and methods, however, as made clear in this paper, extracting accurate information from remote sensing data and GIS databases for coastal geomorphological applications is a nontrivial challenge that requires the combined knowledge and skills of information scientists and geomorphologists.

关键词： coastal geomorphology geographic information system (GIS) spatial analysis threedimensional visualization

Derivative Synthesis of Wanpeinine A,a Major Steroidal Alkaloid from Fritillaria shuchengensis

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Chinese Herbal Medicines 2010年第2期2卷 141-144页

作者： WEN Juan,ZHOU Xian-li,YAN Ren-long,HUANG Shuai,WANG Yin-hui school of Life science and engineering,{3.,chengdu 61003.,china school of Life science and engineering Southwest Jiaotong UniversityChengdu 610031China

Objective To design and synthesize derivatives of wanpeinine A,the main steroidal alkaloid isolated from the plant Fritillaria shuchengensis,and further study on the structure-activity relationship of the steroidal *** Acylation and alkylation were used to synthesize the derivatives and their structures were identified via NMR and *** The acylation of wanpeinine A(1) produced 3.,6α-diacetylwanpeinine A(2),3.,6α-dipropionyl-wanpeinine A(3.,3.,6α-dichloracetylwanpeinine A(4),3.,6α-dibenzoylwanpeinine A(5),and 3.-methoxy-acylwanpeinine A(6).The alkylation of wanpeinine A formed 3.,6α-dimethoxymethylwanpeinine A(7).Conclusion All compounds are new except for 3.,6α-diacetylwanpeinine A.

关键词： Fritillaria shuchengensis steroid alkaloid wanpeinine A

A New Approach for Performance Evaluation of TCP over Interference-Limited Wireless Channels over Interference Wireless Channels

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Journal of Electronic science and Technology of china 2003年第1期1卷 18-21页

作者： LUO Rui FAN Pingzhi(school of Computer and Communications Enginerring,southwest jiaotong university chengdu 61003. {3.) school of Computer and Communications Enginerring Southwest Jiaotong University Chengdu 610031 China

A new metric for performance evaluation of transport control protocol(TCP) overwireless channels based on the interference-limited characteristics of code division multipleaddress(CDMA) system is *** to the new metric,the performance of TCP over CDMAcorrelated channel for different protocol parameters and different versions is *** resultsshow that appropriate selection of protocol parameters and packet error rate(PER) operation point canimprove significantly the capacity of packet-switched CDMA-based network.

关键词： effective factor capacity code division multiple address(CDMA) transport control protocol(TCP)

A Hammerstein-based Model for Rate-dependent Hysteresis in Piezoelectric Actuator

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A Hammerstein-based Model for Rate-dependent Hysteresis in P...