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A microchip to analyze single crystal growth and size-controllability

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Science China Chemistry 2009年第7期52卷 1014-1020页

作者： PANG YuanFeng LIU JiangJiang LI HaiFang lin jinming The Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology Department of ChemistryTsinghua UniversityBeijing 100084China

A microfluidic device to control single crystallization on the micron scale has been developed. The salt solution was stored in the nano-volume gaps between the arrays of protrudent circular plots in the microchip. The mixed organic solvent was injected into the chip as the counter diffusion phase for crystallization forming. This device provides a liquid-liquid interface through which only one phase flows while the other stays at the fixed plot. Therefore, it is possible to control the position of crystallization on the fixed plot. We can control the size and the uniformity of single crystals from 5 to 50 μm in length by adjusting the relative factors, such as interface lifetime, breeds of the mix-organic solvents and injecting velocities. The longer interface lifetime and lower organic solvent injecting velocities can bring up larger and more asymmetric crystals, which nearly shows the same trend compared with the macroscopic crystallization. Finally, the effect of the surfactant on the crystallization in the microdevice was studied. By adding the surfactant into the liquid-liquid interface, smaller sizes of crystals can be obtained without changing the crystal configuration.

关键词： microfluidic device single crystallization liquid-liquid interface size controllability

On-chip solid phase extraction coupled with electrophoresis using modified magnetic microspheres as stationary phase

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Science China Chemistry 2009年第12期52卷 2287-2294页

作者： LI Hong LI HaiFang CHEN ZhiFeng lin jinming Department of Chemistry Tsinghua UniversityBeijing 100084China Chinese Academy of Inspection and Quarantine Beijing 100123China

A poly(dimethylsiloxane)(PDMS)/glass hybrid microchip for on-line solid phase extraction (SPE) and electrophoresis separation has been developed and evaluated. The SPE microchannel was crossed to the electrophoresis microchannel. All the microfluidic channels were etched on the glass substrate. The magnetic microspheres were coated with hydroxyl-terminated poly-dimethylsiloxane (PDMS-OH) serving as extraction phase,which could be conveniently immobilized into the sample pretreatment channel by magnetic field. The PDMS-OH microspheres were mobilized into and out of the pretreatment channel by injection flow. The 0.1 μmol/L solution of fluorescence isothiocyanate (FITC)-labeled phenylalanine (Phe) was electrically injected into the SPE channel and extracted onto the PDMS-OH microspheres bed. The enriched FITC-labeled Phe was electrically eluted by 9 mmol/L sodium acetate containing 10% acetonitrile and electrically driven into the electrophoresis channel and then separated. The preconcentration factor could reach 87.5 after sufficient extraction. A linear preconcentration curve was obtained with the initial FITC-labeled Phe concentration ranging from 6 nmol/L to 300 nmol/L (R2=0.9922) with 200 s loading time. The detection limit (S/N=3) for the FITC-labeled Phe was 3 nmol/L.

关键词： microfluidic device solid phase extraction magnetic microspheres hydroxyl-terminated poly-dimethylsiloxane

Lipid profiling of mammalian cells with in situ matrix-assisted laser desorption ionization-mass spectrometry

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Science China Chemistry 2014年第3期57卷 442-446,1-3页

作者： ZHANG YanDong LI HaiFang MA Yuan lin jinming Beijing Key Laboratory of Microanalytical Methods and Instrumentation The Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology Department of Chemistry Tsinghua University

The analysis of cellular lipids and phospholipids has been of continuously increasing research interest due to the importance of these molecules in psychological *** this work,a mass spectrometry-based method for direct,in situ analysis of lipids in cells was *** cells were directly cultured on ITO-coated glass and then analyzed by matrix-assisted laser desorption ionization-mass spectrometry(MALDI-MS).The matrix application process was achieved by electrospray coating,which produced a homogenous layer of matrix crystal on the *** detection results and reproducibility are *** this method,a profile of abundant membrane lipids is generated,which is characteristic of cell *** conclusion,this in situ MALDI-MS cellular lipid analysis method provides a platform for sensitive and robust molecular profiling of mammalian cells.

关键词： lipid profiling MALDI-MS linear discriminative analysis

Sensitized chemiluminescence reaction between hydrogen peroxide and periodate of different types of Mn-doped ZnS quantum dots

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Chinese Science Bulletin 2010年第30期55卷 3479-3484页

作者： LIU JunXiao CHEN Hui lin ling LU Chao lin jinming State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology Beijing 100029 China Department of Chemistry Tsinghua University Beijing 100084 China

In this work,different types of Mn-doped ZnS QDs were prepared and applied to study of the chemiluminescence reaction of hydrogen peroxide and periodate. The effects of the size of nanoparticles,shell protection and the stabilizing agents on chemilu-minescence intensity were studied. The results indicated that the size of quantum dots was not the only factor to enhance the intensity of chemiluminescence system. Different stabilizing agents and the silica film protection will also influence the performance of the quantum dots in the chemiluminescence reaction. A CL spectrum was examined by using a series of high-energy cut-off optical filters and a possible mechanism of the CL was also proposed.

关键词：化学发光反应过氧化氢量子点 ZnS 锰掺杂类型高碘敏化

Exploring the correlation between temperature and crime:A case-crossover study of eight cities in America

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Journal of Safety Science and Resilience 2024年第1期5卷 13-36页

作者： jinming Hu Xiaofeng Hu Xin’ge Han Yan lin Huanggang Wu Bing Shen School of Information Technology and Cyber Security People’s Public Security University of ChinaBeijing 100038China Center for Capital Social Safety People’s Public Security University of ChinaBeijing 100038China China Association for Public Safety Beijing 100084China School of Emergency Management and Safety Engineering China University of Mining and TechnologyBeijing 100083China School of International Police Studies People’s Public Security University of ChinaBeijing 100038China

Recent years have seen increasing academic interest in exploring the correlation between temperature and ***,it is uncertain whether similar long-term trends or seasonality(rather than causal effect)of temper-ature and crime is the major reason for the observed correlation between *** explore whether there is still a correlation between temperature and crime when long-term trends and seasonal cycles are filtered out,we use the Kalman filter to decompose the time series of temperature and crimes,and then the fast Fourier transform is used to calculate the exact circle of their seasonality *** on that,the box-plot method and linear regression are used to explore the correlation between temperature residuals and crime *** results show that more than half of the crime types have similar seasonal cycles(approximately 1 year)to that of ***,the daily residual analyses show that temperature residuals have a positive correlation with assault and robbery residuals in all cities,whose average slopes are more than *** other four types of crimes vary greatly from case to *** temperature residuals show a weak correlation with the residuals of some crime types.

关键词： Time series decomposition Crime Temperature Kalman filter Fast fourier transform

Determination of Trace Silver( Ⅰ ) in Basic Aqueous Solution by Electrochemiluminescence of a New Reagent 6-(2-Hydroxy-4-Diethylaminophenylazo)-2,3-Dihydro-1,4-Phthalazine-1,4-Dione

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Chemical Research in Chinese Universities 1991年第1期7卷 32-36页

作者： An Jingru lin jinming (Department of Chemistry, Fuzhou University, Fuzhou) To whom correspondence should be addressed.

The electrochemiluminescence (ECL) of a new reagent 6- (2-hydroxy- 4 diethy laminophenylazo)-2,3-dihydro-1 ,4-phthalazine-1,4-dione (HDEA) in a basic aqueous so lution was studied by using the apparatus designed by ourselves. Trace amounts of silver ( Ⅰ ) shows a significant effect on the efficiency of light emission of HDEA during a positive trigonometrical wave pulse was exerted on the solution. The linear relationship between the light intensity and the concentration of silver( Ⅰ ) occurs in the range of 5. 0×10-8 to 3. 0×10-8 mol/L Ag(Ⅰ ) in a medium of KOH-KCl-HDEA (pH= 12. 8). The detection limit of the method is 2. 0×10-8 mol/LAg( Ⅰ ), and the r. s. d. for 1.0×10-7 mo)/L Ag ( Ⅰ ) is 5%. Of 21 metal ions concerned, only nickel( Ⅱ ), cerium( Ⅳ ) and cobalt( Ⅱ ) interfere the silver detection seriously; Ⅰ and Br also have some interference.

关键词： Electrochemiluminescence Reagent Silver 6 ( 2 Hydroxy-4 diethy laminophenylazo)-2,3-dihydro-1 4-phthalazine 1 ,4-dione

The first CICEM held last September

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Electricity 1992年第2期 24-25页

作者： lin jinming Huazhong Univ. of Science and Technology

The first China InternationalConference on Electrical Ma-chines was held in Wuhan on September 18-20, 1991. The conference was supported byChina Association for Science and Technol-ogy and ICEM (Europe), and was sponsoredby CSEE, CES and IEE (London). A total of165 participants attended the conference,coming from relevant academic, researchand educational institutions as well as R & Dand engineering faculties in the power ondmanufacturing industries in China andabroad. The conference proceedings con-tained 186 papers contributed by authors of18 different countries.

关键词： proceedings Wuhan educational institutions attended compensated coming discussions please committee

CHIRAL SEPARATION AND DETERMINATION OF ANTIPARKINSONIAN DRUG ROTIGOTINE AND RELATED CHIRAL IMPURITIES BY CAPILLARY ZONE ELECTROPHORESIS USING DUAL CYCLODEXTRIN SYSTEM

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CHIRAL SEPARATION AND DETERMINATION OF ANTIPARKINSONIAN DRUG...

AUTOMATIC, ON-linE MONITORING OF THE ORGANIC POLLUTANTS IN THE SEAWATER USING THE HOME-MADE LUMINOMETER

第十二届北京分析测试学术报告会暨展览会(BCEIA 2007)

作者： Baolin CHU Baoyuan GUO jinming lin State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology Department of Chemistry Tsinghua University State Key Laboratory of Environmental and Ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences

The pharmaceutical quality control is of great importance for maximizing the efficacy and the safety of the drug therapy and the economy of the production of *** and toxicological characteristics often vary between enantiomers of the racemic drug because of the enantioselective biological interactions and ***,the determination of individual enantiomers is

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AUTOMATIC, ON-LINE MONITORING OF THE ORGANIC POLLUTANTS IN T...