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长江中游湿地保护及综合利用刍议

湘潭师范学院学报（自然科学版） 2002年第1期24卷 68-71页

作者：石超艺李长安中国地质大学地球科学学院武汉430074

湿地这一独特的生态系统因处于陆地生态系统与水体生态系统之间而具有高生产力和生物与生态多样性的特点 ,同时又因处于过渡地带而极易遭到破坏 ,生态系统极为脆弱。长江中游湿地由于人类对其不合理的开发和利用 ,遭到了极大的破坏。我... 详细信息

湿地这一独特的生态系统因处于陆地生态系统与水体生态系统之间而具有高生产力和生物与生态多样性的特点 ,同时又因处于过渡地带而极易遭到破坏 ,生态系统极为脆弱。长江中游湿地由于人类对其不合理的开发和利用 ,遭到了极大的破坏。我们应采取一系列保护及综合利用该区湿地资源的措施 ,以实现其可持续发展 ,并达到取得最佳经济、社会、生态效益的目的。

关键词：长江中游湿地资源综合利用可持续发展生态系统生态保护

An Extended Hierarchical Trusted Model for Wireless Sensor Networks

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Wuhan university Journal of Natural sciences 2006年第6期11卷 1489-1492页

作者： DU Ruiying XU Mingdi ZHANG Huanguo school of Computer Wuhan University Wuhan 430072 Hubei China

Cryptography and authentication are traditional approach for providing network security. However, they are not sufficient for solving the problems which malicious nodes compromise whole wireless sensor network leading to invalid data transmission and wasting resource by using vicious behaviors. This paper puts forward an extended hierarchical trusted architecture for wireless sensor network, and establishes trusted congregations by three-tier framework. The method combines statistics, economics with encrypt mechanism for developing two trusted models which evaluate cluster head nodes and common sensor nodes respectively. The models form logical trusted-link from command node to common sensor nodes and guarantees the network can run in secure and reliable circumstance.

关键词： wireless sensor networks security trust reputation

Design and Parameters Tune of High Precision Diode Laser Temperature Controller

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Design and Parameters Tune of High Precision Diode Laser Tem...

2.d International Symposium on Advanced Optical Manufacturing and Testing Technologies

作者： Sun Li and Bao Jian school of Information and Computer, Anhui Agricultural university, Hefei, P.R.{2. Anhui Institute of Optics and Fine Mechanic, Chinese Academy {3., Hefei, P.R.{2.

＜正＞The emitting frequency of a diode laser is very sensitive to operating temperature. In the design of the temperature controller of a diode laser, it is important that the control parameters of PID should be tuned to match with the characteristic of the controlled target in order to get an optimal correcting effect. In the experiments, two methods of determining PID parameters, Ziegler-Nichols and critical level of proportion methods, were used, and the approximate same results were obtained. The measured result shows the controlling precision of the temperature controller is ＋2.℃ after PID parameters are tuned.

关键词： Diode laser PID corrector Temperature control

测定粮食、水果、蔬菜稀土总量的二溴羧基偶氮胂比色法

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分析测试学报 2001年第1期20卷 69-71页

作者：胡谟彪胡烈宇罗玲四川省农业科学院分析测试中心四川成都610066 南京大学化学学院江苏南京210093

以一定比例的镧、铈、镨、钕、钐的氧化物配制的混合标准溶液在酸性条件下与二溴羧基偶氮胂反应 ,63.nm处的吸光度在0～1.5mg/L范围内符合比耳定律 ,检出限为1.5μg/L,相关系数为0.9995。方法不需加掩蔽剂。试样实测结果的相对标准偏差<... 详细信息

以一定比例的镧、铈、镨、钕、钐的氧化物配制的混合标准溶液在酸性条件下与二溴羧基偶氮胂反应 ,63.nm处的吸光度在0～1.5mg/L范围内符合比耳定律 ,检出限为1.5μg/L,相关系数为0.9995。方法不需加掩蔽剂。试样实测结果的相对标准偏差<7 % (n=5) ,加标回收率在84 %～108%之间。

关键词：稀土总量二溴羟羧基偶氮胂粮食水果蔬菜比色法测定方法

A General Search Method Based on Social Communities in P2. Networks

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A General Search Method Based on Social Communities in P2P N...

The 2.10 IEEE International Conference on Progress in Informatics and Computing

作者： Mo Hai Shuhang Guo school of Information Central university of Finance and Economics Beijing {2.

＜正＞With the increase of the amount of information stored in P2. networks,how to search the information satisfying users’ needs efficiently becomes very *** researches on search algorithms focus on increasing search efficiency（measured by the length of routing path） or decreasing search cost（measured by the number of messages） at the cost of sacrificing the recall ***,there is no work which increases search efficiency,decreases search cost and increase the recall *** this paper,we propose a general search method which can be applied in both unstructured P2. networks and structured P2. *** this method,social communities are formed dynamically on top of P2. overlay *** social community is made up of peers who share similar characteristics, such as interests,search behavior,*** characteristics are dynamic,so the social communities will change as any peer’s characteristics have *** this method,a search request is forwarded by taking use of the social *** results show our proposed method achieves a higher search efficiency,a lower search cost and a higher recall rate compared with traditional search algorithms.

关键词： P2. networks search efficiency search cost social community

Stabilization of atractylone liposomes by surfactant in supercritical carbon dioxide meduim

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Stabilization of atractylone liposomes by surfactant in supe...

2.09 International Conference of Natural Products and Traditional Medicine(ICNPTM’ 09)

作者： Zhen Wen 1* Man Ren2.Bo Liu1 Zongkun Zheng1 Xinkui You1 Yitao Pu1(1.school of chemistry and chemical engineering Shenzhen university Shenzhen 518060 {2. 2.State Key Laboratory of Organic Geochemistry Chinese Academy of {3. Guangzhou 510640 {2. Guangzhou 510640 {2.)

In order to form stable liopsome suspensions in supercritical carbon dioxide（SC-CO2.,the atractylone was incorporated into liposomes by rapid expansion from supercritical to surfactant solution process（RESSS）.In this process,surfactant provided stabilization for liposomes by preventing bubbles overflowing and liposomes agglomeration during the spraying *** stabilization ability could be controlled by changing expansion processing conditions such as amount of surfactant and solution flow *** the solution of liposomal materials and atractylone was sprayed into 5.0% Poloxamer l88 solution at a flow rate of 2./min,the entrapment efficiency and average particle size of liposomes were found to be 87.2.% and 12. nm *** with the liposomes prepared by thin film dispersion,the liposomes stabilized by Poloxamer l88 using RESSS process showed smaller particle size and exhibited a uniform and narrow-dispersed distribution,which achieved the standards of Chinese pharmacopoeia.

关键词： liposome surfactant supercritical carbon dioxide rapid expansion atractylone

Researches on detection of 3.D underground cave based on TEM technique

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Researches on detection of 3-D underground cave based on TEM...

中国科学院地质与地球物理研究所第11届（2.11年度）学术年会

作者： G.Q.Xue·Y.J.Yan·J.L.Cheng Key Laboratory of Mineral Resources, Institute of Geology and Geophysics, Chinese Academy of sciences,Beijing 10002.,china Department of Engineering Mechanics,{2. of Mechanics Civil and Architecture,Institute of Vibration Engineering, Northwestern Polytechnical {3.,Xi’an 710072. People’s Republic of china State Key Laboratory of Coal Resources and Safe Mining, china {3. of Mining and Technology, Beijing 100083.china

Because of unreasonable coal mining in china, there are many unknown underground caves,and the inhabited environment of humans is threatened by many geologic hazards,such as cracking of the buildings,ground subsidence,*** make the coal companies aware of the harmfulness of these hazards,it is urgent to determine the reasons for the *** this paper,transient electromagnetic method(TEM) is used to detect the ground resistance caves,instead of the time-consuming and expensive direct drilling *** results of the 3.D synthetic model and real field survey data are given. The results showed that the TEM method can be used to detect a complicated air-filled underground 3.D cave and coincide with the results of direct drilling survey.

关键词： Transient electromagnetic method Underground cave detection 3.D modeling

Solution structure and function of proteins relevant to pre-mRNA splicing

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生物物理学报 2009年第S1期25卷 76-76页

作者： Yunyu Shi, Jihui Wu, Xiaojuan Huang, Xingsheng Wang Hefei National Laboratory for Physical sciences at Microscale and school of Life sciences, {3. of Science and Technology of china, Hefei, Anhui, 2.3}02., P.R.china

Pre-mRNA splicing is a dynamic process. It is catalyzed by the spliceosome which is a large machine formed by an ordered interactions of several small nuclear ribonucleoproteins, U1,

关键词： mRNA Solution structure and function of proteins relevant to pre-mRNA splicing

Inversion of Ionospheric Electron Density from GPS Beacon Observations

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Wuhan university Journal of Natural sciences 2003年第4A期8卷 1116-1120页

作者： Zou Yu-hua,Xu Ji-sheng  school of Electronic Information,Wuhan university,Wuhan 4{2.072.Hubei,china school of Electronic Information Wuhan UniversityWuhan 430072 Hubei China

This paper studies the mathematical foundation of time-dependent three-dependent three-dimensional (3.D) computerized ionospheric tomography (CIT) for reconstructing ionospheric electron density,N_e,from ground-based GPS beacon obser\|vations,After simplifying the relation between N_e and time, the time-dependent 3.D inversion in consideration is reduced to a 3.D tomography with incomplete projections. To see clearly the effects of the incompleteness on the quality of reconstruction under 3.D condition,the fromula of 3.D parallelbeam tomography is deduced theoretically. After establishing the mathematical foundation,simulations based on actual GPS ray paths with the help of the IRI-90 model are performed, and reasonable time-dependent 3.D distribution images of N_e are obtained when taking proper layout of the network and allowing variable resolutions. The quality of the reconstruction is rather good when compared with the images from the IRI90 model directly. Therefore, results in this paper demonstrate that imaging of the ionospheric electron density distribution from GPS beacon observations is reasonable in theory and feasible in pratice.

关键词： ionosphere time-dependent three-dimensional CT GPS beacon