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Local and non-local sources of airborne particulate pollution at Beijing——The ratio of Mg/Al as an element tracer for estimating the contributions of mineral aerosols from outside Beijing

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Science china chemistry 2005年第3期48卷 253-264页

作者： HAN Lihui1, ZHUANG Guoshun1,2,3. SUN Yele1 & WANG Zifa3.1. The Center for Atmospheric Environmental Study, department of chemistry, Beijing Normal university, Beijing 100875, {3. 2. Center for Atmospheric chemistry Study, department of Environmental Science & Engineering, Fudan university, Shanghai 20043., {3. 3. LAPC/NZC, Institute of Atmospheric Physics, CAS, Beijing 100029, {3. 1. The Center for Atmospheric Environmental Study Department of Chemistry Beijing Normal University 100875 Beijing China 2. Center for Atmospheric chemistry Study Department of Environmental Science & Engineering Fudan University 200433 Shanghai China 3. Institute of Atmospheric Physics CAS LAPC/NZC 100029 Beijing China

A new element tracer technique has firstly been established to estimate the contri-butions of mineral aerosols from both inside and outside Beijing. The ratio of Mg/Al in aerosol is a feasible element tracer to distinguish between the sources of inside and outside Beijing. Mineral aerosol, inorganic pollution aerosol mainly as sulfate and nitrate, and organic aerosol are the major components of airborne particulates in Beijing, of which mineral aerosol accounted for 3.%―67% of total suspended particles （TSP）, 10%―70% of fine particles （PM2.5）, and as high as 74% and 90% of TSP and PM2.5, respectively, in dust storm. The sources from outside Beijing contributed 62% （3.%―86%） of the total mineral aerosols in TSP, 69% （52%―90%） in PM10, and 76% （59%―93.） in PM2.5 in spring, and 69% （52%―83.）, 79% （52%―93.）, and 45% （7%―79%） in TSP, PM10, and PM2.5, respectively, in winter, while only20% in summer and autumn. The sources from outside Beijing contributed as high as 97% during dust storm and were the dominant source of airborne particulates in Beijing. The contributions from outside Bei-jing in spring and winter are higher than those in summer, indicating clearly that it was related to the various meteorological factors.

关键词： mineral aerosol local sources non-local sources dust storm re-suspended dust element tracer technique.

Synthesis and Efficiency of a SphericalMacroporous Epoxy-dicyandiamide ChelateResin for Preconcentrating and SeparatingTrace Au, Hg, Pd and Ru from Samples

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Chemical Research in Chinese Universities 2001年第2期17卷 168-174页

作者： GONG Bo-lin, LI Xue-qiang and WANG Feng-rong (department of chemistry, Ningxia university, Yinchuan 750021, {3.) CHANG Xi-jun (department of chemistry, Lanzhou university, Lanzhou 73.000, {3.) Ningxia Univ Dept Chem Yinchuan 750021 Peoples R China Lanzhou Univ Dept Chem Lanzhou 730000 Peoples R China

A novel spherical macroporous epoxy-dicyandiamide chelate resin was synthesized simply and rapidly from epoxy resin and used for the preconcentration and separation of trace amounts of Au (Ⅲ ), Hg (Ⅱ ), Pd (Ⅳ) and Ru (Ⅲ) ions from solution samples. The analyzed ions can be quantitatively concentrated by the resin at a flow rate of 2. 0 mL/min at pH 4, and can also be desorbed with 15 mL of 4 mol/L HCl + 0. 3.g thiourea from the resin column with recoveries of 96. 5%-99. 0%. After the chelate resin was reused for 7 times, the recoveries of these ions were still over 92%, and 400-1 000 times of excess of Fe(Ⅲ ), Al(Ⅲ ), Ni( II), Mn( Ⅱ ), Cr (Ⅲ ), Cu ( Ⅱ ), Cd (Ⅱ ) and Pb (Ⅱ ) caused little interference with the determination of these ions by an inductively coupled plasma optical emission spectrometer (ICP-OES ). The capacities of the resin for the analytes are in the range of 0. 3.~0. 92 mmol/g. The RSDs of the proposed method are in the range of 1. 1 % ~4. 0% for each kind of the analyzed ions. The recoveries of a standard added in real solution samples are between 96. 5% and 98. 5%, and the results for the analyzed ions in a powder sample are in good agreement with their reported values.

关键词： Concentration Separation Macroporous epoxy-dicyandiamide chelate resin Gold Mercury Palladium and ruthenium.

Synthesis and Crystal Structure of CoCl(ieaa)(C_(10)H_7-ieai)(C_(10)H_7NH_2)

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Chinese Journal of Structural chemistry 2002年第1期21卷 22-25页

作者： FENG Yun-Long (department of chemistry, Zhejiang Normal university Jinhua 23.004,{3.) department of chemistry Zhejiang Normal University Jinhua 231004

The title complex CoCl(ieaa)(C10H7-ieai)(C10H7NH2), C3.H3.ClCoN4O7, Mr= 679.00; (ieaa- and C10H7-ieai- are the anions of isonitrosoethylacetoacetate and its N-a- naphthylamine derivative of Schiff base, respectively, C10H7NH2 is a-naphthylamine), crystallizes in the monoclinic system, space group P21/n with a=11.846(2), b=23.912(5), c=12.783.3.? b=116.54(3., V=3.3.(1)?, Dc=1.3.2g/cm3. F(000)=1408, Mr=679.00, m(MoKa)=0.665mm-1, Z=4, final R=0.0584 and wR=0.13.8 for 4177 observed reflections (I ≥ 2s(I)). A nitrogen atom of the ieaa- ligand and two nitrogen atoms of the C10H7-ieai- ligand define one of the triangular faces in the distorted octahedral geometry about the cobalt atom. The title complex contains isonitroso-b-ketoimine.

关键词： cobalt complex isonitroso-b-ketoimine Schiff base crystal structure

CMC surfaces in the hyperbolic 3.space

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Chinese Science Bulletin 1998年第7期43卷 547-550页

作者： YU Zuhuan 1, 2 and LI Zhenqi 1, 3.1. Institute of Mathematics, Fudan university, Shanghai 20043., china 2. department of Mathematics,Sichuan Union university, Chengdu 610064, china 3. department of Mathematics, Nanchang university, Nanchang 3. nstitute of Mathemalics Fudan University Shanghai China department of Mathematics Sichuan Union University Chengdu China department of Mathematics Nanchang University Nanchang China

CMC-H surfaces satisfying H≥1 are studied. It is proved that these surfaces possess a natural representation which is a generalization of the Bryant’s result.

关键词： hyperbolic space CMC surface Weierstrass representation.

Boron nitride microribbons strengthened and toughened alumina composite ceramics with excellent mechanical,dielectric,and thermal conductivity properties

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Journal of Advanced Ceramics 2024年第4期13卷 496-506页

作者： jilin Wang Dongping Lu Weiping Xuan Yuchun Ji Ruiqi Chen Shaofei Li Wenbiao Li Wenzhuo Chen Shilin Tang Guoyuan Zheng Fei Long Guangxi Key Laboratory of Optical and Electronic Materials and Devices Collaborative Innovation Center for Exploration of Nonferrous Metal Deposits and Efficient Utilization of ResourcesSchool of Materials Science and EngineeringGuilin University of TechnologyGuilin 541004China Key Laboratory of New Processing Technology for Nonferrous Metals and Materials of Ministry of Education Guilin University of TechnologyGuilin 541004China School of Materials Science and Engineering Peking UniversityBeijing 100871China department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityKowloon 999077Hong KongChina

Aluminum oxide(Al_(2)O_(3.)ceramics have been widely utilized as circuit substrates owing to their exceptional *** this study,boron nitride microribbon(BNMR)/Al_(2)O_(3.composite ceramics are prepared using spark plasma sintering(SPS).This study examines the effect of varying the amount of toughened phase BNMR on the density,mechanical properties,dielectric constant,and thermal conductivity of BNMR/Al_(2)O_(3.composite ceramics while also exploring the mechanisms behind the toughening and increased thermal conductivity of the fabricated *** results showed that for a BNMR content of 5 wt%,BNMR/Al_(2)O_(3.composite ceramics displayed more enhanced characteristics than pure Al_(2)O_(3.*** particular,the relative density,hardness,fracture toughness,and bending strength were 99.95%±0.025%,3..11±1.5 GPa,5.42±0.21 MPa·m^(1/2),and 3.5±2.5 MPa,*** values represent increases of 0.76%,70%,3.%,and 25%,respectively,compared with the corresponding values for pure Al_(2)O_(3.***,during the SPS process,BNMRs are subjected to high temperatures and pressures,resulting in the bending and deformation of the Al_(2)O_(3.matrix;this leads to the formation of special thermal pathways within *** dielectric constant of the composite ceramics decreased by 25.6%,whereas the thermal conductivity increased by 45.6%compared with that of the pure Al_(2)O_(3.*** results of this study provide valuable insights into ways of enhancing the performance of Al_(2)O_(3.-based ceramic substrates by incorporating novel BNMRs as a second *** improvements are significant for potential applications in circuit substrates and related fields that require high-performance materials with improved mechanical properties and thermal conductivities.

关键词： boron nitride microribbons/aluminum oxide(BNMRs/Al_(2)O_(3.)composite ceramics boron nitride microribbon(BNMR) spark plasma sintering(SPS) strengthening and toughening thermal conductivity

Constraints on Characteristics and Distribution of Gas Hydrate and Free Gas Using Broad-Band Processing of Three-Dimensional Seismic Data

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Journal of Ocean university of china 2024年第5期23卷 1233-1247页

作者： WANG Xiujuan ZHOU jilin LI Sanzhong LI Lixia LI Jie LI Yuanping WANG Linfei SU Pibo JIN Jiapeng GONG Zhi State Key Laboratory of Offshore Natural Gas Hydrate Beijing 100028China Frontiers Science Center for Deep Ocean Multispheres and Earth System Key Laboratory of Submarine Geosciences and Prospecting TechniquesMOE and College of Marine GeosciencesOcean University of ChinaQingdao 266100China Laboratory for Marine Mineral Resources Qingdao Marine Science and Technology CenterQingdao 266237China CNOOC Research Institute Co. Ltd.Beijing 100028China CNOOC china Limited Shenzhen BranchShenzhen 518054China Guangzhou Marine Geological Survey China Geological SurveyGuangzhou 510000China

Gas hydrate drilling expeditions in the Pearl River Mouth Basin,South china Sea,have identified concentrated gas hydrates with variable ***,free gas and the coexistence of gas hydrate and free gas have been confirmed by logging,coring,and production tests in the foraminifera-rich silty sediments with complex bottom-simulating reflectors(BSRs).The broad-band processing is conducted on conventional three-dimensional(3.)seismic data to improve the image and detection accuracy of gas hydratebearing layers and delineate the saturation and thickness of gas hydrate-and free gas-bearing *** geophysical attributes extracted along the base of the gas hydrate stability zone are used to demonstrate the variable distribution and the controlling factors for the differential enrichment of gas *** inverted gas hydrate saturation at the production zone is over 40% with a thickness of 90 m,showing the interbedded distribution with different boundaries between gas hydrate-and free gas-bearing ***,the gas hydrate saturation value at the adjacent canyon is 70%,with 3.-m-thick patches and linear *** lithological and fault controls on gas hydrate and free gas distributions are demonstrated by tracing each gas hydrate-bearing ***,the BSR depths based on broad-band reprocessed 3. seismic data not only exhibit variations due to small-scale topographic changes caused by seafloor sedimentation and erosion but also show the upward shift of BSR and the blocky distribution of the coexistence of gas hydrate and free gas in the Pearl River Mouth Basin.

关键词： gas hydrate free gas shift of BSR broad-band processing

Online uniform machine covering with the known largest size

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Progress in Natural Science:Materials International 2007年第11期17卷 1271-1278页

作者： Cao Shunjuan1,2 and Tan Zhiyi1,3.1. department of Mathematics, Zhejiang university, Hangzhou 3.0027, china 2. department of Mathematics, Zhejiang Forestry university, Hangzhou 3.13.0, china 3. State Key Laboratory of CAD & CG, Zhejiang university, Hangzhou 3.0027, china) department of Mathematics Zhejiang University Hangzhou 310027 China department of Mathematics Zhejiang Forestry University Hangzhou 311300 China State Key Laboratory of CAD & CG Zhejiang University Hangzhou 310027 China

This paper investigates the semi-online scheduling problem with the known largest size on two uniform machines. The objective is to maximize the minimum machine completion time. Both lower bounds and algorithms are given. Algorithms are optimal for the majority values of s≥1, where s is the speed ratio of the two machines. The largest gap between the competitive ratio and the lower bound is about 0.064. Moreover, the overall competitive ratio 2 matches the overall lower bound.

关键词： scheduling and covering uniform machine design and analysis of algorithm online competitive ratio

Synthesis and Conductivity of Undecatungstocobaltoruthenic Polyoxometallic Acid

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Chemical Research in Chinese Universities 2012年第1期28卷 1-3页

作者： XU Sheng-xian1,2, WU Qing-yin2 and YAN Wen-fu3.1. School of chemistry and Chemical Engineering, Jiangxi Science & Technology Normal university, Nanchang 3.0013. P. R. china 2. {3. of chemistry, Zhejiang university, Hangzhou 3.0027, P. R. china 3. State Key Laboratory of Inorganic Synthesis and Preparative chemistry, jilin university, Changchun 13.012, P. R. china Zhejiang Univ Dept Chem Hangzhou 310027 Zhejiang Peoples R China Jiangxi Sci & Technol Normal Univ Sch Chem & Chem Engn Nanchang 330013 Peoples R China jilin Univ State Key Lab Inorgan Synth & Preparat Chem Changchun 130012 Peoples R China

Undecatungstocobaltoruthenic polyoxometallic acid H7[Ru（H2O）CoW11O3.] 22H2O was synthesized by the stepwise acidification and the stepwise addition of solutions of the component elements as well as the ion ex changing-cooling method. The optimal proportion of the component compound and the pH of the synthesis reaction were given. The product was characterized by means of inductively coupled plasma（ICP）, IR, UV and thermal analy sis. The IR and UV results indicate that H7[Ru（H2O）CoW11O3.] 22H2O possesses the Keggin structure. The results of AC impedance measurement show that its proton conductivity is 2.3.×10-3.S/cm at room temperature（295 K） and a relative humidity of 75%.

关键词： Polyoxometallic acid Keggin structure Conductivity Ruthenium

COMPARISON　THEOREMS　TO　BOUNDARY　VALUE　PROBLEMS　FOR　ORDINARY　DIFFERENTIAL　EQUATIONS

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Chinese Annals of Mathematics,Series B 1994年第2期15卷 165-172页

作者： LI YONG WANG HUAIZHONG(department of Matehematics,jilin university, Changchun 13.023. jilin, china) jilin UNIV DEPT MATHCHANGCHUN 130023PEOPLES R CHINA

A unified approach is given to several classes of nonlinear boundary value problems, and some previous existence theorems are extended.

关键词： Boundary value problem Existence theorem Brouwer degree,Schauder's fixed point theorem.