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THE INTENSITYCHARACTERISTICS OF DIATOMIC IONINSECONDARY ION MASS SPECTROMETRY

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Chinese Science Bulletin 1984年第11期29卷 1469-1474页

作者：汪国良林卓然 scientific instrument factory Academia Sinica Beijing Institute of Geology State Seismological Bureau Beijing

Ⅰ. INTRODUCTION In recent years, ion microprobe secondary ion mass spectrometry has found a wide application in ***, isotopic and molecular ion mass interferences have posed a problem in qualitative or quantitative i... 详细信息

关键词： SIMS isotopic interpretation qualitative posed isotopes Probability mostly derivation overlapping

N,N,O-Tridentate One-dimensional Methyl-bridged Heterobimetallic Complex: Synthesis, Crystal Structure and Catalytic Activity

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Chinese Journal of Structural Chemistry 2020年第7期39卷 1343-1349页

作者： HUA Yu-Peng PANG Jing-Lin GAO Yan-Peng WEI Xue-Hong Ordos Institute of Technology Ordos 017000Inner MongoliaChina scientific instrument Center Shanxi UniversityTaiyuan 030006China

The sequential reaction of the N,N,O-tridentate ligand HOC(CH2)5CH2N(Me)CH2CH2NMe2(LH)in diethyl ether with AlEtCl2 and MeLi afforded a lithium-aluminum complex containing a polymeric structure of one-dimensional chain[{-LiOC(CH2)5CH2N(Me)CH2CH2NMe2}AlMe2CH3-}n](1),which was characterized by 1H,13C NMR spectra,elemental analyses and single-crystal X-ray diffraction *** 1 crystallizes in triclinic,space group P1 with a=10.526(3),b=10.949(3),c=17.799(4)?,β=76.211(11)°,V=1915.3(8)?3,Dc=1.014 g·cm–3,F(000)=648 andμ=0.104 mm–*** addition,the heterobimetallic complex 1 was used to catalyze the Meerwein-Ponndorf-Verley(MPV)reaction and exhibited excellent catalytic activities in good yield(up to 97%).

关键词： heterobimetallic complex synthesis characterization catalytic reaction

Synthesis and Crystal Structure of a New Guanidinatoaluminium Complex and Its Utilityin the Meerwein-Ponndorf-Verley Reduction

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Chinese Journal of Structural Chemistry 2018年第4期37卷 624-630页

作者：韩红斐李文娟张少峰魏学红 Department of Chemistry Taiyuan Normal University The School of Chemistry and Chemical Engineering Shanxi University scientific instrument Center Shanxi University

The treatment of pyrrolidine （C4HsNI-I） with sequentially trimethylaluminum andcarbodiimide CyN--C=NCy in a molar ratio of 1 ：1：1 in the presence of O2 afforded a newguanidinatoaluminurn complex, [{（C4HsN）C（NCy）2}AIMe（/I-OMe）]2 （1）, which was characterizedby elemental analyses, 1H, 13C NMR spectra and single-crystal X-ray diffraction analysis. ComplexI crystallizes in monoclinic, space group P21/c with a = 9.8330（9）, b = 8.5786（8）, c = 24.159（2） A,β= 92.927（2）°, V= 2035.3（3） A3, Dc = 1.141 g cm^-3, F（000） = 768 and μ= 0.110 mm^-l. In addition,complex 1 was used to catalyze the Meerwein-Ponndorf-Verley （MPV） reduction and 1 as apre-catalyst at low catalyst loadings （5 tool%） exhibited good catalytic activity for the reduction ofa series of aldehydes to the corresponding alcohols in good yields （cony. up to 99%）.

关键词： guanidinatoaluminium complex synthesis crystal structure MPV reaction

Ultravilolet-radiation-induced graft polymerization of acrylamide onto the melt-blown polypropylene filter element by dynamic method

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Journal of Environmental Sciences 2007年第11期19卷 1387-1392页

作者： WU Lin-lin WU Guang-xia XU Shu-guang ZHONG Hui SHEN Ying-jie LIU He-zhi HUANG Zheng-ming YANG Xin-bo YUAN Zong-huan TANG Lian-yi LIN Xiang-wei ZHANG Shao-lai ZHANG Wei-jun Research Center for Eco-environmental Sciences Chinese Academy of Sciences Beijing 100085 China Insititute for Drug and instrument Control of Health Dept GLD of PLA Beijing 100071 China 302 Hospital of PLA Beijing 100039 China 301 Hospital of PLA Beijing 100853 China The Greatwall Pharmaceutical factory of Beijing Beijing 100071 China Beijing Tong Ren Tang Company Limited scientific Research Institute Beijing 100011 China

By dynamic method under UV irradiation, commercial melt-blown polypropylene （PPMB） filter element was modified with acrylamide （AAm） using benzophenone （BP） as initiator. Attenuated total reflection-Fourier transform infrared spectroscopy and scanning electron microscope verified that polyacrylamide chain was grafted on the fiber surface of PPMB filter element. Elemental content analysis with energy dispersive X-ray of fibers revealed that the polymerization content in the inner part of filter element was relatively higher than that in the outer. Degree of grafting changed with initiator concentration, monomer concentration, reaction temperature and reached 2.6% at the reaction condition： CBp=0.06 mol/L, CAAm=2.0 mol/L, irradiation time： 80 min, temperature： 60℃. Relative water flux altered with the hydrophilicity and pore size of filter element. In the antifouling test, the modified filter gave greater flux recovery （approximately 70%） after filtration of the water extract of Liuweidihuang, suggesting that the fouling layer was more easily reversible due to the hydrophilic nature of the modified filter.

关键词： melt-blown polypropylene filter element UV-induced graft polymerization surface modification dynamic method

Identification and characterization of phenolics and terpenoids from ethanolic extracts of Phyllanthus species by HPLC-ESI-QTOF-MS/MS

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Journal of Pharmaceutical Analysis 2017年第4期7卷 214-222页

作者： Sunil Kumar Awantika Singh Brijesh Kumar Sophisticated Analytical instrument Facility CSIR-Central Drug Research InstituteLucknow 226031Uttar PradeshIndia Academy of scientific and Innovative Research (AcSIR) New Delhi 110025India

Phyllanthus species plants are a rich source of phenolics and widely used due to their medicinal properties. A liquid chromatography–tandem mass spectrometry(LC–MS/MS) method was developed using high-pressure liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry(HPLC-ESI-QTOFMS/MS) for the identification and characterization of quercetin, kaempferol, ellagic acid and their derivatives in ethanolic extracts of Phyllanthus species. The chromatographic separation was carried out on Thermo Betasil C_8 column(250 mm×4.5 mm, 5 μm) using 0.1% formic acid in water and 0.1% formic acid in methanol as the mobile phase. The identification of diagnostic fragment ions and optimization of collision energies were carried out using 21 reference standards. Totally 51 compounds were identified which include 21 compounds identified and characterized unambiguously by comparison with their authentic standards and the remaining 30 were tentatively identified and characterized in ethanolic extracts of P. emblica, P. fraternus, P. amarus and ***.

关键词： Phyllanthus species HPLC-ESI-QTOF-MS/MS Phenolics

Wrist joint moments of walker-assisted gait:a study of biomechanics and instrumentation

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仪器仪表学报 2007年第9期28卷 1537-1542页

作者： Ming Dong Wang Weijie Wan Baikun Hu Yong Department of Biomedical Engineering and scientific instrument Tianjin University Tianfin 300072 China Department of Orthopaedic and Trauma Surgery University of Dundee UK Department of Orthopaedics and Traumatology Hong Kong University Hong Kong SAR China

While walkers are commonly prescribed to improve patient stability and ambulatory ability,quantitative study of the biomechanical and functional requirements for effective walker use is *** investigate the changes in wrist joint moments that occur with the use of a standard walker,a strain gauge-based walker instrumentation sys- tem was developed for the measurement of wrist joint *** walker dynamometer was integrated with an up- per extremity biomechanical *** system data were collected for twelve healthy,right-handed young a- dults following informed *** upper extremity kinematic data were acquired with a six-camera motion a- nalysis *** joint moments at the wrist were determined in the three clinical planes using the inverse dy- namics *** showed that during a walker-assisted gait there were several typical demands of wrist abduc- tor,adductor,flexor and external *** interesting'bare phase'of wrist joint moments was also found in phase angle[-30°,30°]of gait *** description of wrist joint moments during walker-assisted gait may pro- vide insight into walker use parameters and rehabilitative strategies.

关键词：生物力学仪表助行器辅助步法桡腕关节矩

Effect of radiation-induced color centers absorption in optical fibers on fiber optic gyroscope for space application

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Chinese Physics B 2016年第8期25卷 216-221页

作者：金靖李亚张祖琛吴春晓宋凝芳 School of instrument Science and Optic-electronics Engineering Beihang University

The effects of color centers＇ absorption on fibers and interferometric fiber optical gyroscopes（IFOGs） are studied in the paper. The irradiation induced attenuation（RIA） spectra of three types of polarization-maintaining fibers（PMFs）, i.e.,P-doped, Ge-doped, and pure silica, irradiated at 100 Gy and 1000 Gy are measured in a wavelength range from 1100 nm to1600 nm and decomposed according to the Gaussian model. The relationship of the color centers absorption intensity with radiation dose is investigated based on a power model. Furthermore, the effects of all color centers＇ absorption on RIA and mean wavelength shifts（MWS） at 1300 nm and 1550 nm are discussed respectively. Finally, the random walk coefficient（RWC） degradation induced from RIA and the scale factor error induced by MWS of the IFOG are simulated and tested at a wavelength of 1300 nm. This research will contribute to the applications of the fibers in radiation environments.

关键词： color centers' absorption radiation-induced attenuation mean wavelength shift fiber optical gyroscope

Ultra-low power anti-crosstalk collision avoidance light detection and ranging using chaotic pulse position modulation approach

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Chinese Physics B 2016年第7期25卷 250-257页

作者：郝杰巩马理杜鹏飞卢宝杰张帆张海涛付星 Center for Photonics and Electronics Department of Precision Instrument Tsinghua University

A novel concept of collision avoidance single-photon light detection and ranging（LIDAR） for vehicles has been demonstrated, in which chaotic pulse position modulation is applied on the transmitted laser pulses for robust anti-crosstalk purposes. Besides, single-photon detectors（SPD） and time correlated single photon counting techniques are adapted, to sense the ultra-low power used for the consideration of compact structure and eye safety. Parameters including pulse rate, discrimination threshold, and number of accumulated pulses have been thoroughly analyzed based on the detection requirements, resulting in specified receiver operating characteristics curves. Both simulation and indoor experiments were performed to verify the excellent anti-crosstalk capability of the presented collision avoidance LIDAR despite ultra-low transmitting power.

关键词： collision avoidance chaotic pulse position modulation time-correlated single photon counting anti-crosstalk

Determination of trace Pb(II), Cd(II) and Zn(II) using differential pulse stripping voltammetry without Hg modification

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Science China Chemistry 2013年第12期56卷 1749-1756页

作者： LIN Qi LIN HongMei ZHANG YuanHui RONG MingCong KE HuiXian TANG XinHua CHEN Xi Key Lab of Global Change and Marine-Atmospheric Chemistry SOA Third Institute of Oceanography SOA Department of Chemistry College of Chemistry and Chemical Engineering Xiamen University Xiamen Standard scientific instrument Co. Ltd.

In this work,we reported a simultaneous determination approach for Pb(II),Cd(II)and Zn(II)atμg L 1concentration levels using differential pulse stripping voltammetry on a bismuth film electrode(BiFE).The BiFE could be prepared in situ when the sample solution contained a suitable amount of Bi(NO)3,and its analytical performance was evaluated for the simultaneous determination of Pb(II),Cd(II)and Zn(II)in *** determination limits were found to be 0.19μg L 1for Zn(II),and0.28μg L 1for Pb(II)and Cd(II),with a preconcentration time of 300 *** BiFE approach was successfully applied to determine Pb(II),Cd(II)and Zn(II)in tea leaf and infusion samples,and the results were in agreement with those obtained using an atomic absorption spectrometry *** Hg usage,the in situ preparation for BiFE supplied a green and acceptability sensitive method for the determination of the heavy metal ions.

关键词： bismuth film electrode differential pulse stripping voltammetry tea leaves tea infusion