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On-line Preconcentration and Determination of Trace Metals in Water Samples by Flow Injection Combined with Flame Atomic Absorption Spectrometry via Calix[4]arene Carboxylic Acid Packed Micro-column

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Chemical Research in Chinese Universities 2012年第1期28卷 26-30页

作者： GUO Da-wang, ZHAO Xiao-wei, JIA Qiong and ZHOU Wei-hong college of Chemistry, jilin university, changchun 130012, P. R. china jilin Univ Coll Chem Changchun 130012 Peoples R China

An adsorbent calix[4]arene carboxylic acid was employed as the adsorption material for on-line flow in jection（FI） micro-column preconcentration coupled with flame atomic absorption spectrometry（FAAS） determination of trace heavy metals（Cu, Pb, Co, Ni and Cd）. Parameters such as the pH, loading time and flow rate of sample, and the concentration, volume and flow rate of eluent were optimized. The enrichment factors are 50.0, 56.5, 11.6, 12.1 and 19.1 for Cu, Pb, Co, Ni, and Cd, respectively, and a sample throughput of 20 h–1 was obtained. The limits of de tection for Cu, Pb, Co, Ni, and Cd were in a range of 1.56―3.91 μg/L, and the relative standard deviations（RSDs） were less than 2.76%（n=7）. Furthermore, the proposed method was successfully applied to the determination of Cu, Pb, Co, Ni, and Cd in certified reference materials and various water samples.

关键词： Calixarene carboxylic acid Preconcentration Flow injection Metal ion Flame atomic absorptionspectrometry(FAAS)

Magnetic Energy of Force-Free Fields with Detached Field Lines

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Chinese Journal of Astronomy and Astrophysics 2003年第6期3卷 555-562页

作者： Guo-Qiang Li and You-Qiu HuSchool of earth and Space sciences, university of Science and Technology of china, Hefei 230026 School of earth and Space sciences University of Science and Technology of China Hefei 230026

Using an axisymmetrical ideal MHD model in spherical coordinates, we present a numerical study of magnetic configurations characterized by a levitating flux rope embedded in a bipolar background field whose normal field at the solar surface is the same or very close to that of a central dipole. The characteristic plasma β (the ratio between gas pressure and magnetic pressure) is taken to be so small (β = 10-4) that the magnetic field is close to being force-free. The system as a whole is then let evolve quasi-statically with a slow increase of either the annular magnetic flux or the axial magnetic flux of the rope, and the total magnetic energy of the system grows accordingly. It is found that there exists an energy threshold: the flux rope sticks to the solar surface in equilibrium if the magnetic energy of the system is below the threshold, whereas it loses equilibrium if the threshold is exceeded. The energy threshold is found to be larger than that of the corresponding fully-open magnetic field by a factor of nearly 1.08 irrespective as to whether the background field is completely closed or partly open, or whether the magnetic energy is enhanced by an increase of annular or axial flux of the rope. This gives an example showing that a force-free magnetic field may have an energy larger than the corresponding open field energy if part of the field lines is allowed to be detached from the solar surface. The implication of such a conclusion in coronal mass ejections is briefly discussed and some comments are made on the maximum energy of force-free magnetic fields.

关键词： Sun: magnetic fields - Sun: coronal mass ejections (CMEs) -methods: numerical

Effect of solution concentration on the structured order and optical properties of short-chain polyene biomolecules

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Science china(Physics,Mechanics & Astronomy) 2010年第9期53卷 1646-1650页

作者： OUYANG ShunLi1,2,SUN ChengLin1,2,ZHOU Mi1,2,LI DongFei2,WANG WeiWei1,2,QU GuanNan1,LI ZuoWei1,2,GAO ShuQin1 & YANG JianGe3 1 State Key Laboratory of Superhard Materials,jilin university,changchun 130012,china 2 college of Physics,jilin university,changchun 130023,china 3 The ordnance Engineering Department,Air Force Aviation university,changchun 130022,china 1. State Key Laboratory of Superhard Materials Jilin University Changchun 130012 China2. College of Physics Jilin University Changchun 130023 China3. The ordnance Engineering Department Air Force Aviation University Changchun 130022 China

We have measured the Raman spectra and UV-Vis absorption spectra of linear polyene biomolecules(β-carotene and lycopene) in CS2 at low concentrations(10-6-10-10 mol/L).With decreasing concentration,all the carbon-carbon vibrations form a coherent mode in ordered β-carotene and lycopene due to extended π-conjugation that gives strong electron-phonon coupling,which leads to an anomalous experimental *** observed an extremely high Raman scattering cross section(RSCS) and the Raman activities in β-carotene and lycopene are characterized by intensive overtones and ***,the UV-Vis absorption bands become narrower.

关键词： molecular structured order Raman spectroscopy Raman scattering cross section

URBANIZATION AND ITS IMPACTS ON WATER ENVIRONMENT IN TUMEN RIVER BASIN

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Chinese Geographical Science 2002年第3期12卷 273-281页

作者： WANG Shi-jun,WANG Dan,YANG Xiang-h ua(college of Urban and Environmental sciences,Northeast Normal university,changchun 130024,P.R.china) college of Urban and Environmental sciences Northeast Normal University Changchun 130024 P. R. China

The trans-boundary scope of the Tume n River Basin(TRB)going through china,Russia and DPRK has been defined,and on the basis of this,status of urbanization and its impacts on water environment in recent 20years in TRB have been *** n in TRB can be characterized as:1)There is medium level of overall urbanization in *** distance still exists compared with developed *** it is lower than the average urbanization level of Russia and higher than that o f china.2)There is unbalanced distribution of urbanization development in *** in china part owns the c haracter of low starting point and hi gh-speed *** Russia part,charac-ter of urbanization can be described as high starting point and stable *** DPRK part,urbanizatio n level is low,and motive power lacks.3)Due to large population,in china part there is broader region urbanized,larger radius and higher frequency of human activities,which lead to heavier pressure on ***,the paper has point-ed that impacts of urbanization on wa ter environment are as follows:1)Urban population growth and industr y develop-ment increase the demand for freshwa ter,and also exacerbate the contrad iction between limited water supply and increas-ing freshwater demand.2)Urban infrastructure doesn’t match with urban productive function especially treatment facili-ties,which results in the pollution of the Tumen River.3)The pollution situation in the Tumen River got peak point in1995,and presently,such situation has been improved in great scale,due to effective interventions ***,there still exist 2enterprises that are urgent to be ***,pollution of municipal sewage will become more and more apparent.4)The influence of urbanization on soil is mainly caused by industrial effl uent and slag,and pollut-ed water *** and water l oss has also been a serious problem caused by urbanization.5)Urbanization results in the decrease of wet

关键词： tumen river basin (TRB) urbanization water environment

The Republic of Yemen Petroleum Overview

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Global Geology 2001年第2期6卷 159-161,199页

作者： NEDHAM Mohammed Darsi (college of earth Science, jilin university, 130061 P.R.china) college of earth Science Jilin University 130061 P.R. China

AbstractYemen located on the southwest corner of the Arabian Peninsula. It is known that Yemen is important to world energy markets because of its oil and natural gas resources as well as its strategic location at the Bab el-Mandab strait linking the Red Sea and the Gulf of Aden. Due to the Ministry of Oil and Mineral Resources (MOMR, 1998E) the Yemeni Oil Production was estimated to be 385 000 barrels per day (bbl/d), Oil Consumption was 69 000 bbl/d and Net Oil Exports was 316 000 barrels per day (bbl/d). On 1999 the Yemeni Proven Oil Reserves was estimated to be 4 billion barrels and the Natural Gas Reserves was estimated to be 16.9 trillion cubic feet (Tcf) (Ministry of Oil and Mineral Resources, 1999). At this time, many researchers, scientific expeditions and foreign companies are interested in Yemen. This paper discussed the petroleum overview of the Republic of Yemen. In my opinion, Yemen is not just going to attract all with its oil and gas discoveries in the near future, but also with its new geological data and information.

关键词： Republic of Yemen, Petroleum

Terrain classification based on adaptive weights with airborne LiDAR data for mining area

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中国有色金属学会会刊：英文版 2011年第S3期21卷 648-653页

作者： LI Hui-ying1, WANG Zhi2, SUN Ya-feng1, LI Wen-hui1 1. college of Computer Science and Technology, jilin university, changchun 130012, china 2. college of Resources and Civil Engineering, Northeastern university, Shenyang 110004, china [a] college of Computer Science and Technology Jilin University Changchun 130012 China [b] college of Resources and Civil Engineering Northeastern University Shenyang 110004 China

The fast high-efficiency inspection for mining subsidence of mine area is a reliable way for forecasting accident and evaluating losing expense. In order to monitor mining subsidence of exploitation mine efficiently, LiDAR data were used and a novel strip division method was brought forward based on separating-treatment theory, which divided the mass of discrete three-dimensional point cloud data into a series of parallel strips and reduced the dimension in each strip. Polynomial fitting algorithm based on the adaptive weights, which located in the range of the strip, was used for classification complex terrain data of mine-area. The results show that LiDAR datamation can be greatly reduced. In the mean time, the time spending for calculation is shortened, and computational complexity is simplified. Therefore, high-efficiency terrain classification of LiDAR point cloud method can be great beneficial to monitoring environment of mine area.

关键词： mining subsidence airborne LiDAR strip division adaptive weights

Simulating the Folding Pathway of RNA Secondary Structure Using the Modified Ant Colony Algorithm

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Journal of Bionic Engineering 2010年第4期7卷 382-389页

作者： Jun Yu~(1,2),Changhai Zhang~(1,2),Yuanning Liu~(1,2),Xin Li~(1,2) 1.college of Computer Science and Technology,jilin university,changchun 130012,P.R.china 2.Key Laboratory of Symbolic Computation and Knowledge Engineering (Ministry of Education,china) jilin university,changchun 130012,P.R.china [a] college of Computer Science Technology Jilin University Changchun 130012 P. R. China [b] Key Laboratory of Symbolic Computation Knowledge Engineering (Ministry of Education China) Jilin University Changchun 130012 P. R. China

A new method for simulating the folding pathway of RNA secondary structure using the modified ant colony algorithmis *** a given RNA sequence,the set of all possible stems is obtained and the energy of each stem iscalculated and stored at the initial ***,a more realistic formula is used to compute the energy ofmulti-branch loop in the following *** a folding pathway is simulated,including such processes as constructionof the heuristic information,the rule of initializing the pheromone,the mechanism of choosing the initial andnext stem and the strategy of updating the pheromone between two different *** by testing RNA sequences withknown secondary structures from the public databases,we analyze the experimental data to select appropriate values *** measure indexes show that our procedure is more consistent with phylogenetically proven structures thansoftware RNAstructure sometimes and more effective than the standard Genetic Algorithm.

关键词： RNA secondary structure folding pathway ant colony algorithm

Discovery of a pterodactylid pterosaur from the Yixian Formation of western Liaoning,china

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Chinese Science Bulletin 2001年第13期46卷 1112-1117页

作者： WANG Xiaolin & LU Junchang1. Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of sciences, Beijing 100044, china 2. college of earth sciences and Resources, china university of Geo-sciences, Beijing 100083, china 3. Department of Geological sciences, Southern Methodist university, Dallas, TX 75275, USA Institute of Vertebrate Paleontology Chinese Academy of Sciences Beijing 100044 China

A well-preserved pterosaur with nearly complete skull is described from the Lower Cretaceous Yixian Formation at Sihetun in western Liaoning. It is characterized by a low and long crestless skull, slender and pointed teeth, long metacarpal, nearly equal length of metatarsals I -III and short pedal digit V. It is referred to a new genus and species of the family Pterodactylidae: Haopterus gracilis gen. et sp. nov. This is the first pterosaur with a nearly complete skull from the Jehol Biota; it also represents the first non-controversial fossil record of Pterodactylidae in Asia. Haopterus is more derived than Pterodactylus from the Late Jurassic Solnhofen in Germany. This discovery extends the distribution of the family Pterodactylidae from Europe and Africa to Asia and its latest occurrence from the Late Jurassic to the Early Cretaceous. The discovery of Haopterus gracilis provides further evidence for the study of the originand radiation of the Jehol Biota; it also sheds new light on the evolution and

关键词： western Liaoning Early Cretaceous Yixian Formation Pterodactylidae.

Using multi-matching system based on a simplified deformable model of the human iris for iris recognition

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Journal of Bionic Engineering 2004年第3期1卷 183-190页

作者： MING Xing , XU Tao , WANG Zheng-xuan 1 2 3 1. college of Computer Science and Technology, Nanling Campus,jilin university, 5988 Renmin Street,changchun 130022, P. R. china 2. college of Mechanical Science and Engineering, Nanling Campus,jilin university, 5988 Renmin Street, changchun 130022, P. R. china 3. college of Computer Science and Technology, Qianwei Campus,jilin university, 10 Qianwei Road, changchun 130012, P. R. china. jilin university jilin university jilin university

A new method for iris recognition using a multi-matching system based on a simplified deformable model of the human iris was proposed. The method defined iris feature points and formed the feature space based on a wavelet transform. In the matching stage it worked in a crude manner. Driven by a simplified deformable iris model, the crude matching was refined. By means of such multi-matching system, the task of iris recognition was accomplished. This process can preserve the elastic deformation between an input iris image and a template and improve precision for iris recognition. The experimental results indicate the va- lidity of this method.

关键词： iris recognition wavelet transform feature points deformable model