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Nonlinear analysis on the coupling process of electromagnetic vibrator and earth

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Science china Earth Sciences 2005年第8期48卷 1175-1182页

作者： CHEN Zubin1,2. TENG Jiwen2. LIN Jun1, ZHANG Linhang1 & JIANG Zhongjin1 1. Institute of Intelligent Instrument & measurement Control Technology, Jilin University, Changchun 13002., china 2. Institute of Geology & Geophysics, Chinese Academy of Sciences, Beijing 10002., china 1. Institute of Intelligent Instrument & measurement Control Technology Jilin University 130026 Changchun China 2. Institute of Geology & Geophysics Chinese Academy of Sciences 100029 Beijing China

The linear model based on the hydraulic pressure vibrator has been no longer adaptable to the electromagnetic vibrator. In order to realize the effective transmission of the limited energy from the vibrator to the ground, it is important to study the coupling model of the electromagnetic vibrator and the earth. In this paper, a nonlinear restore term was introduced to the coupling model because of the existence of a large amount of harmonics in the vibrator baseplate. The nonlinear vibration analysis was applied to the model by the multiscale method. In the course of energy transmission from the vibrator to the ground, ultraharmonic resonance was used to explain the generation of harmonics. An improved scheme was advanced to select the cross correlation reference signal in the vibrator seismic exploration. Good application results were obtained in field experiments.

关键词： vibrator, coupling model, electromagnetic, nonlinear vibration.

Polynomial analysis of canopy spectra and biochemical component content inversion

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Science china Earth Sciences 2005年第10期48卷 1780-1791页

作者： YAN Chunyan1, LIU Qiang1, NIU Zheng1, WANG Jihua2. HUANG Wenjiang2.& LIU Liangyun 2.1. State Key Laboratory of Remote Sensing Science, Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University, Beijing 100101, china 2. National Engineering Research center for Information Technology in Agriculture, Beijing 100089, china State Key Laboratory of Remote Sensing Science Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University Beijing china National Engineering Research center for Information Technology in Agriculture Beijing china

A polynomial expression model was developed in this paper to describe directional canopy spectra, and the decomposition of the polynomial expression was used as a tool for re-trieving biochemical component content from canopy multi-angle spectra. First, the basic formula of the polynomial expression was introduced and the physical meaning of its terms and coeffi-cients was discussed. Based on this analysis, a complete polynomial expression model and its decomposition method were given. By decomposing the canopy spectra simulated with SAILH model, it shows that the polynomial expression can not only fit well the canopy spectra, but also show the contribution of every order scattering to the whole reflectance. Taking the first scattering coefficients a10 and a01 for example, the test results show that the polynomial coefficients reflect very well the hot spot phenomenon and the effects of viewing angles, LAI and leaf inclination angle on canopy spectra. By coupling the polynomial expression with leaf model PROSPECT, a canopy biochemical component content inversion model was given. In the simulated test, the canopy multi-angle spectra were simulated by two different models, SAILH and 4-SCALE re-spectively, then the biochemical component content was retrieved by inverting the coupled polynomial expression + PROSPECT model. Results of the simulated test are promising, and when applying the algorithm to measured corn canopy multi-angle spectra, we also get relatively accurate chlorophyll content. It shows that the polynomial analysis provides a new method to get biochemical component content independent of any specific canopy model.

关键词： polynomial expression, canopy spectra, decomposition, biochemical component content, inversion.

Comprehensive evaluation of mechanism of "chimney effect" using principles of magnetism, geochemistry and mineralogy

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Chinese Science Bulletin 1998年第9期43卷 743-748页

作者： LIU Qingsheng 1, CHENG Tongjin 2.and LIU Shugen 3 1. Department of Applied Geophysics, china University of Geosciences, Wuhan 430074, china 2. {2. of Petroleum Geochemistry, china National Star Petroleum Corporation, Hefei 2.002., china 3. The St Department of Applied Geophysics China University of Geosciences Wuhan China center of Petroleum Geochemistry China National Star Petroleum Corporation Hefei China The State Key Laboratory of Oil/Gas Reservoir Geology and Exploitation of china Chengdu Institute of Technology Chengdu China

Study of forming mechanism of "chimney-effect" (CE) has important significance for basic theory and applications of non-seismic geophysical and geochemical methods locating oil/gas reservoirs. The theoretical basis of comprehensive evaluation of mechanism of CE using principles of magnetism, geochemistry and mineralogy has been reviewed, with the problems to be solved: (ⅰ) study for the relationship between process of oil/gas migration and geochemical field; (ⅱ) analysis of genesis of magnetic, geochemical and mineralogical anomaly; (ⅲ) interpretation of surface soil magnetism and geochemical anomaly combined with seismic data.

关键词： chimney effect (CE) hydrocarbon microseepage oil/gas accumulation.

Orbit determination for geostationary satellites with the combination of transfer ranging and pseudorange data

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Science china(Physics,Mechanics & Astronomy) 2010年第9期53卷 1746-1754页

作者： GUO Rui1,2.3,4,HU XiaoGong2.4,LIU Li1,WU XiaoLi1,HUANG Yong2.4 & HE Feng1 1 Beijing Global Information Application and Development center,Beijing 100094,china 2.Shanghai Astronomical Observatory,Chinese Academy of Sciences,Shanghai 2.0030,china 3 Graduate University of Chinese Academy of Sciences,Beijing 100049,china 4 Space Navigation and Positioning Technology,Laboratory of Shanghai Municipal,Shanghai 2.0030,china 1. Beijing Global Information Application and Development center Beijing 100094 China2. Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030 China3. Graduate University of Chinese Academy of Sciences Beijing 100049 China4. Space Navigation and Positioning Technology Laboratory of Shanghai Municipal Shanghai 200030 China

Geostationary satellites(GEOs) play a significant role in the regional satellite navigation *** experiments show that the clock corrections could be mitigated through a single strategy or double differencing strategies for a navigation constellation,but for the mode of individual GEO orbit determination,high precision orbit and clock correction could not be obtained in the orbit determination based on the pseudorange data.A new GEO combined precise orbit determination(POD) strategy is studied in this paper,which combines pseudorange data and C-band transfer ranging *** strategy overcomes the deficiency of C-band transfer ranging caused by limited stations and tracking time *** the combination of transfer ranging and pseudorange data,clock corrections between the GEO and the stations can be estimated simultaneously along with orbital parameters,maintaining self-consistency between the satellite ephemeris and clock correction *** error covariance analysis is conducted to illuminate the contributions from the transfer ranging data and the psudoranging *** data collected for a Chinese GEO satellite with 3 C-band transfer ranging stations and 4 L-band pseudorange tracking stations,POD experiments indicate that a meter-level accuracy is *** root-mean-square(RMS) of the post-fit C-band ranging data is about 0.2.3 m,and the RMS of the post-fit pseudorange is 0.408 *** component errors of the POD experiments are independently evaluated with the satellite laser ranging(SLR) data from a station in Beijing,with the residual RMS of 0.076 *** SLR evaluation also suggests that for 2.h orbital predication,the predicted radial error is about 0.404 m,and the clock correction error is about 1.38 *** for the combination of one C-band transfer ranging station and 4 pseudorange stations,POD is able to achieve a reasonable accuracy with the radial error of 0.2.0 m and the 2.h predicted radial error of 0.888 *** syn

关键词： satellite navigation precise orbit determination pseudorange equipment ranging delay GEO SLR

Expression and function analysis of the metallo-thionein-like (MT-like) gene from Festuca rubra in Chlamydomonas reinhardtii chloroplast

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Science china(Life Sciences) 2008年第12期51卷 1076-1081页

作者： HAN SiHai1,2. HU ZhangLi1 & LEI AnPing1 1 Institute of Eco-Environment, College of Life Science, Shenzhen University, Shenzhen 518060, china 2.Research center for Analytical Instrumentation, State Key Lab of Industrial Control Technology, Institute of Cyber-Systems and Control, {2. University, hangzhou 310058, china 1. Institute of Eco-Environment College of Life Science Shenzhen University Shenzhen 518060 China 2. Research center for Analytical Instrumentation State Key Lab of Industrial Control Technology Institute of Cyber-Systems and Control Zhejiang University Hangzhou 310058 China

The cDNA of the metallothionein-like (MT-like) gene from Festuca rubra cv. Merlin was optimized with bias codon of Chlamydomonous reinhardtii chloroplast genome. The optimized MT-like gene was de-livered into C. reinhardtii chloroplast and the transgenic strains expressing MT-like gene was obtained. PCR-Southern blot and RT-PCR-Southern blot analysis demonstrated that the MT-like gene was inte-grated into chloroplast genome of C. reinhardtii and expressed at the transcriptional level. The cad-mium binding capacity of the transgenic C. reinhardtii was determined by hydride generation-atomic fluorescence spectrometry (HG-AFS) and the binding properties were analyzed. Results showed that the transgenic C. reinhardtii expressing the MT-like gene exhibited remarkably higher Cd2. binding capacity and grew to higher densities at toxic Cd2. concentrations (40-100 μmol/L) than the wild type strain, and that the IC50 of Cd2. (3-d treating ) to algal cell growth of transgenic strain was 55.43% higher than that of the wild type strain, indicating that the Cd2. binding capacity and Cd2. tolerance of C. reinhardtii was enhanced through the expression of the foreign MT-like gene in chloroplast.

关键词： Chlamydomonas reinhardtii chloroplast metallothionein-like (MT-like) gene cadmium binding properties

Crystal structure and single crystal EPR of (NH_4)_2.15-crown-5)_3[Cu(mnt)_2. and (NH_4)_2.benzo-15-crown-5)_4[Cu(mnt)_2.·0.5H_2.

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Science china Chemistry 2007年第5期50卷 607-613页

作者： SUI YunXia1, WEN LiLi2. ZHANG Huan3 & MENG QingJin2.1 center of Modern analysis, Nanjing University, Nanjing 2.0093,{2. 2.State Key Laboratory of Coordination Chemistry, Coordination Chemistry Institute, Nanjing University, Nanjing 2.0093,{2. 3 Jiangnan Institute of Computing Technology, Wuxi 2.4083,{2. 1. center of Modern analysis Nanjing University Nanjing 210093 China 2. State Key Laboratory of Coordination Chemistry Coordination Chemistry Institute Nanjing University Nanjing 210093 China 3. Jiangnan Institute of Computing Technology Wuxi 214083 China

The X-ray crystal structures of (NH4)2.15-crown-5)3[Cu(mnt)2. (1) and(NH4)2.benzo-15-crown-5)4-[Cu(mnt)2. ident to 0.5H2. (2. were *** single crystals arecomposed of distinct structures of ammonium-crown ether supramolecular cation and [Cu(mnt)2.^(2.)*** triple-decker dication in complex 1 and a sandwich dimmer in complex 2.wereobserved.X-Band EPR studies on the single crystals of both complex 1 and complex 2.have been carriedout at room temperature,which revealed that complex 2.showed a perfect hyperfine structure of Cuwhereas that of complex 1 could not be *** principal values and direction cosines of theprincipal axes of the g and A tensors were computed by a least-squares fitting *** spindensity of Cu(ll) was estimated according to the principal values of the A tensors and compared wellwith the results calculated based on DFT method.

关键词： supramolecular cation, H-bonding interaction, EPR, g and A tensors, DFT

A method of constructing a database-free optimal dynamical system and a global optimal dynamical system

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Science china(Physics,Mechanics & Astronomy) 2008年第7期51卷 905-915页

作者： WU ChuiJie1? & WANG Liang2.1 State Key Laboratory of Structural analysis for Industrial Equipment, Dalian University of Technology, Dalian 11602., china 2.Research {2. for Fluid Dynamics, School of Science, PLA University of Science and Technology, Nanjing 2.1101, china 1. State Key Laboratory of Structural analysis for Industrial Equipment Dalian University of Technology Dalian 116024 China 2. Research center for Fluid Dynamics School of Science PLA University of Science and Technology Nanjing 211101 China

In this paper, to overcome the drawbacks of POT which minimize the reminder, not only the optimal functional with minimal residual is put forward, but also the method of global optimization is used. Under the condition of large reminder, the optimal bases can also be obtained through the method of POTres without the approaching of initial conditions. In addition, compared with local optimization, the advantage of global optimization is remarkable. On the one hand, we can expect that the dynamical system based on the global optimal bases will include more information than the ones based on the local optimal bases, since the global optimal bases are much more precise than the local optimal bases. On the other hand, from the point of view of error, the global optimal bases are independent of the choice of the object functional and the initial bases.

关键词： dynamical system residual global optimization

Interannual variability of Antarctic Oscillation and its influence on East Asian climate during boreal winter and spring

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Science china Earth Sciences 2006年第5期49卷 554-560页

作者： FAN Ke1,2.3 & WANG Huijun2.1. Nansen-Zhu International Research center, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 10002., china 2. Department of Atmospheric Science, Yunnan University, Kunming 650091, china 3. Graduate University of the Chinese Academy of Sciences, Beijing 100049, china 1. Nansen-Zhu International Research center Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China 2. Department of Atmospheric Science Yunnan University Kunming 650091 China 3. Graduate University of the Chinese Academy of Sciences Beijing 100049 China

The interannual variability of Antarctic Oscillation (AAO) and its influence on East Asian climate during both boreal winter and spring are addressed. The results show that the positive AAO anomaly decreases the cold activity over East Asia during both boreal winter and spring. AAO-related barotropic meridional teleconnection from Antarctic to Arctic is found through analysis of mean me- ridional circulations. This meridional teleconnection is remarkable over Eurasia during boreal winter and over the Pacific Ocean during boreal spring. The results also show that zonal mean zonal wind at high latitudes in Southern Hemisphere has well positive correlation with that of Eurasia during boreal winter and has negative correlation with Pacific North American teleconnection (PNA) during boreal spring, which again display the meridional teleconnection. Thus, local meridional teleconnection is a possible linkage for interaction of circulations at mid-high latitudes between both hemispheres.

关键词： Antarctic Oscillation, Eurasian west wind, meridional teleconnection, mean meridional circulation.

Rapid quantification of the metabolite of valacyclovir hydrochloride in human plasma by liquid chromatography-tandem mass spectrometry

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Journal of Pharmaceutical analysis 2010年第2期22卷 83-90页

作者： Yuan Tian1,2.Hui Lin1,2.Xue-Yu Zhang1,2.Zun-Jian Zhang1,2.Guo-Guang Mao31. Key Laboratory of Drug Quality Control and Pharmacovigilance (china Pharmaceutical University),Ministry of Education,Nanjing 2.0009 2. center for Instrumental {2.,china Pharmaceutical University,Nanjing 2.0009 3. Department of Clinical Pharmacology,Wannan Medical College,Wuhu 2.1000,china. Key Laboratory of Drug Quality Control and Pharmacovigilance (china Pharmaceutical University) Ministry of Education Nanjing 210009 China center for Instrumental analysis China Pharmaceutical University Nanjing 210009 China Department of Clinical Pharmacology Wannan Medical College Wuhu 241000 China

Objective To establish a rapid,sensitive and selective liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the determination of acyclovir (the metabolite of valacyclovir hydrochloride) in human plasma. Methods After addition of ganciclovir as internal standard (IS),plasma samples were prepared by one-step protein precipitation using acetonitrile as precipitant,followed by an isocratic elution with 0.1% formic acid solution-methanol (95∶5,v/v) on an Agilent ZORBAX SB-C18 (150mm×2.1mm i.d.,3.5μm) column. Detection was performed on a triple-quadrupole mass spectrometer utilizing electrospray ionization (ESI) interface operating in positive ion and selected reaction monitoring (SRM) mode with the precursor to product ion transitions m/z 2.6.2.152.1 for acyclovir and m/z 2.6.2.152.1 for the IS. Results The analytical results demonstrated a good linearity over the ranges from 0.005 to 4μg/mL (r=0.9999) for valacyclovir hydrochloride. The relative standard deviations (RSD) of intra-batch and inter-batch were less than 4.06% and 9.2.%,respectively. The limit of detection and lower limit of quantification in human plasma were 2.g/mL and 5ng/mL,respectively. Conclusion The method was simple,sensitive,accurate and reproducible and has been successfully applied to a bioequivalence study of valacyclovir hydrochloride capsules in Chinese healthy male volunteers.

关键词： valacyclovir hydrochloride acyclovir liquid chromatography-tandem mass spectrometry method validation human plasma