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The consideration and choice on exploiting energy source

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chinese Science Bulletin 1999年第18期44卷 1717-1728页

作者： WANG XianbinState key laboratory of Gas Geochemistry, lanzhou {2. of Geology, chinese academy of sciences , lanzhou 730000, China State key laboratory of Gas Geochemistry Lanzhou Institute of Geology Chinese Academy of Sciences Lanxhou China

A problem of petroleum energy crisis will probably be faced in the late 2.st century. It is impossible to discover the giant oil fields again based on the traditional knowledge and theory of petroleum geology. From the global development point of view as well as the situation in China, the five choices of energy source in the future are to ( i ) extend the field of exploration in conventional petroleum and natural gas source, and exploit oil-gas source in ocean and

关键词： energy sources in the future unconventional gas coal hydrogen controllable nuclear fusion 3He source on the moon.

PIXE and INAA studies on ancient potteries from Guangfulin relics in Shanghai

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Progress in Natural Science:Materials International 2007年第11期17卷 1348-1356页

作者： lin Jiawei1, Cheng Huansheng1, Zhang Zhengquan1, Zhang Bin1, Feng Songlin2. Song Jian3, Gao Menghe4 and Zhu Dan1(1. Applied Ion Beam physics laboratory, {2. laboratory of the Ministry of Education, institute of Modern physics, Fudan University, Shanghai 2.0433, China 2. {2. laboratory of Nuclear Analytical Techniques, institute of high energy physics, Beijing 100039, China 3. Shanghai Museum, Shanghai 2.0003, China 4. Department of Cultural Heritage and Museology, Fudan University, Shanghai 2.0433, China) Applied Ion Beam physics laboratory Institute of Modern Physics Fudan University Shanghai 200433 China key laboratory of Nuclear Analytical Techniques Institute of High Energy Physics Beijing 100039 China Shanghai Museum Shanghai 200003 China Department of Cultural Heritage and Museology Fudan University Shanghai 200433 China

This paper reports the study of ancient potteries unearthed from the Guangfulin site in Shanghai. From the external features of these potteries, archeologists can classify them into two different cultural types: liangzhu culture (local culture) and a new culture which might be derived elsewhere, but they can not recognize whether they were produced in the same place. Proton induced X-ray emission (PIXE) and instrumental neutron activation analysis (INAA) were used to measure the chemical compositions of the samples and the results were analyzed using multivariate statistics. We found that the two methods can complement each other and their database can be mutually referenced in the study of ancient potteries. Experimental results show that the compositions of the potteries from the two cultural types are different, which means that the materials for ancient potteries of new culture originate from elsewhere. This supports the archaeologists’ speculation that a group of ancient people migrated to Shanghai from some other places 4000 years ago.

关键词： PIXE INAA factor analysis Guangfulin ancient pottery

Polyfluorenes containing pyrazine units:Synthesis,photophysics and electroluminescence

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Science China Chemistry 2011年第4期54卷 656-665页

作者： WANG Ming,lI Ying,XIE ZhiYuan & WANG liXiang State key laboratory of Polymer {2. and Chemistry Changchun institute of Applied Chemistry,chinese academy of sciences,Changchun 13002.,China State key laboratory of Polymer {2. and Chemistry Changchun institute of Applied Chemistry Chinese Academy of Sciences Changchun China

A series of conjugated copolymers of 9,9-dioctylfluorene and symmetrical pyrazine unit (BY) were synthesized by Suzuki copolymerization and were used as novel light-emitting materials in *** energy transfer was observed in both thin film and *** with the lowest occupied molecular orbital (lUMO) energy level of the polyfluorenes homopolymer (PFO),the lower lUMO energy levels of copolymers indicated that the introduction of the BY unit would be benefit to electron *** turn-on voltages of their single-layer electroluminescent (El) devices (ITO/PEDOT/polymer/liF/Al) were at 6.1-4.0 V,which were much lower than that of PFO (7.0 V).The maximum brightness,current efficiency,and external quantum efficiency of all PFBY copolymers were higher than those of the PFO *** single-layer device of PFBY5 was the best one in the copolymers,with a maximum brightness of 485 cd/m2.a current efficiency of 0.2. cd/A,and an external quantum efficiency of 0.10%.The introduction of PVK and TPBI for the multilayer device of PFBY5 increased the device efficiencies,which showed a maximum brightness of 3012.cd/m2.a maximum current efficiency of 1.81 cd/A,and an external quantum efficiency of 0.66%.

关键词： pyrazine polyfluorenes energy transfer PlED

KINETICS STUDY ON MElT GRAFTING ACRYlIC ACID ONTO llDPE USING REACTIVE EXTRUSION

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chinese Journal of Polymer Science 2005年第6期23卷 603-610页

作者： Qiang Shi lian-chao Zhu Chuan-lun Cai and Jing-hua Yin State key laboratory of Polymer {2. and Chemistry,Changchun institute of Applied Chemistry,chinese academy of sciences,Changchun 13002.,China State key laboratory of Polymer {2. and Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 China

The kinetics of melt grafting acrylic acid （AA） onto linear low density polyethylene （llDPE） by using reactive extrusion was investigated. The polymeric peroxides （POOP and POOH） generated by electron beam irradiation were used to initiate the graft reaction. The samples taken out from the barrel at five ports along screw axis were analyzed by FTIR. The spectra show that both the graft copolymerization and homopolymerization proceed in two stages： the graft degree （or mass of homopolymer） increases linearly with the reaction time in the initial stage, and then gradually in the second stage. The rate of graft copolymerization Rg is always faster than that of homopolymerization Rh in the present system and the activation energy is 131 kJ · mol^-1 for graft copolymerization and 12. kJ · mol^-1 for homopolymeirzation. These results were interpreted in terms of solubility and diffusion of monomer, as well as the reactivity and the concentration of reactive species. The relationships between reaction rate and monomer concentration and peroxide concentration were found to be： Rg ∞ [M]^1.46[POOP＋POOH]^0.53 and Rh ∞ [M] ^1.08[POOH]^0.51, which indicate that the addition of monomer to polymeric radicals is a slow step for the graft copolymerization.

关键词： Graft copolymerization Kinetics Reactive extrusion

Validity of the Bouchet's complementary relationship at 102.observatories across China

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Science China Earth sciences 2009年第5期52卷 708-713页

作者： YU JingJie1,2.ZHANG YongQiang3,lIU ChangMing1,2.1 institute of Geographic sciences and Natural Resources Research,{2. academy of sciences,Beijing 100101,China 2.key laboratory of Water Cycle and Related land Surface Processes,{2. academy of sciences,Beijing 100101,China 3 CSIRO land and Water,PO Box 1666,Canberra ACT 2.01,Australia institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences Beijing China key laboratory of Water Cycle and Related land Surface Processes Chinese Academy of Sciences Beijing China CSIRO land and Water Canberra Australia

Bouchet in 1963 hypothesized that for large homogeneous land surface with minimum advection of heat and moisture,there exists a 1:1 complementary relationship of potential and actual evaporation coupled through land-atmosphere *** complementary relationship has been widely used to estimate regional actual evaporation and explain the pan evaporation *** examine the standardized potential evaporation(potential evaporation divided by wet environment evaporation) at 102.observatories at different elevations across ***,the relationship is appropriate at the low elevations(levation,vapor transfer power becomes much less than radiation energy budget because of lower vapor pressure deficit and stronger global solar *** a result,at the {2. elevations(over 1000 m),the excess energy resulted by limited moisture availability is not enough to be converted into drying power of the *** result suggests that the complementary relationship is asymmetric at the {2. elevations.

关键词： evaporation complementary relationship elevation China

Identification and Categorization of Horizontally Transferred Genes in Prokaryotic Genomes

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Acta Biochimica et Biophysica Sinica 2005年第8期37卷 561-566页

作者： Shuo-Yong SHI~1 xiao-Hui CAI~1 and Da-fu DING~(1,2.) key {2. of Proteomics.institute of Biochemistry and Cell Biology.Shanghai institutes for Biological sciences,chinese academy of sciences,Graduate School of the chinese academy of sciences.Shanghai 2.0031,China ~2.School of life Science & Technology.Shanghai Jiaotong University.Shanghai 2.0030.China key laboratory of Proteomics Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Graduate School of the Chinese Academy of SciencesShanghai 200031 China School of life Science & Technology Shanghai Jiaotong UniversityShanghai 200030 China

Horizontal gene transfer(HGT),a process through which genomes acquire genetic materialsfrom distantly related organisms,is believed to be one of the major forces in prokaryotic genome ***,systematic investigation is still scarce to clarify two basic issues about HGT:(1) what types ofgenes are transferred:and(2.what influence HGT events over the organization and evolution of ***-scale investigations of these two issues will advance the systematical understanding ofHGT in the context of prokaryotic genome *** investigated 82.genomes,we constructed anHGT database across broad evolutionary *** identified four function categories containing a highproportion of horizontally transferred genes:cell envelope,energy metabolism,regulatory functions,andtransport/binding *** biased function distribution indicates that HGT is not completely random;instead,it is under high selective pressure,required by function restraints in ***,wemapped the transferred genes onto the connectivity structure map of organism-specific pathways listed inKyoto Encyclopedia of Genes and Genomes(KEGG).Our results suggest that recruitment of transferredgenes into pathways is also selectively constrained because of the tuned interaction between original *** organization structures still conserve well through evolution even with the recruitment ofhorizontally transferred ***,in pathways whose organization were significantly affected byHGT events,the operon-like arrangement of transferred genes was found to be *** resultssuggest that operon plays an essential and directional role in the integration of alien genes into pathways.

关键词： genome evolution horizontal gene transfer function and pathway analysis

Global Impact and Balancing Act:Deciphering the Effect of Fluorination on B 1s Binding Energies in Fluorinated h‑BN Nanosheets

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Precision Chemistry 2024年第6期2卷 239-244页

作者： Yang xiao Jun-rong Zhang Sheng-Yu Wang Weijie Hua MIIT key laboratory of Semiconductor Microstructure and Quantum Sensing Department of Applied PhysicsSchool of PhysicsNanjing University of Science and Technology210094 NanjingChina

X-ray photoelectron spectroscopy(XPS)is an important characterization tool in the pursuit of controllable fluorination of two-dimensional hexagonal boron nitride(h-BN).However,there is a lack of clear spectral interpretation,and seemingly conflicting measurements *** discern the structure−spectroscopy relation,we performed a comprehensive first-principles study on the boron 1s edge XPS of fluorinated h-BN(F-BN)*** gradually introducing 1−6 fluorine atoms into different boron or nitrogen sites,we created various F-BN structures with doping ratios ranging from 1 to 6%.Our calculations reveal that fluorines landed at boron or nitrogen sites exert competitive effects on the B 1s binding energies(BEs),leading to red or blue shifts in different *** calculations affirmed the hypothesis that fluorination affects 1s BEs of all borons in theπ-conjugated system,opposing the transferability from h-BN to ***,we observe that BE generally increases with higher fluorine concentration when both borons and nitrogens are nonexclusively *** findings provide critical insights into how fluorination affects boron’s 1s BEs,contributing to a better understanding of fluorination functionalization processes in h-BN and its potential applications in materials science.

关键词： X-ray photoelectron spectroscopy Core-electron binding energy Fluorination Hexagonal boron nitride Cluster-periodic method Born-Oppenheimer molecular dynamics

Adsorption of zinc on manganite(γ-MnOOH): particle concentration effect and adsorption reversibility

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Journal of Environmental sciences 2004年第4期16卷 627-630页

作者： QIN Yan-wen1, PAN Gang 1,2., ZHANG Ming-ming1, lI Xian-liang1 (1. State key laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental {2., chinese academy of sciences, Beijing 100085, China. 2. Qingdao University of Science & Technology, Qingdao 2.6042. China) State key laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China.

The adsorption and desorption processes of Zn(Ⅱ) on γ-MnOOH as a function of particle concentrations(C p) were studied. An obvious C p effect was observed in this adsorption system. The degree of adsorption hysteresis increased greatly with the increasing of C p, indicating that the extent of the real metastable-equilibrium states deviating from the ideal equilibrium state was enhanced with the increasing of C p. The C p-reversibility relationship confirmed the metastable-equilibrium adsorption(MEA) inequality(Pan, 1998a), which was the core formulation of the MEA theory. Because the MEA inequality was based on the basic hypothesis of MEA theory that adsorption density Γ is not a state variable, the C p-reversibility relationship gave indirect evidence to the basic hypothesis of MEA theory.

关键词： zinc γ-MnOOH adsorption reversibility

Rational design of superior catalysts from topological semimetals with nontrivial energy window

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Rare Metals 2024年第5期43卷 1956-1964页

作者： Min Zhao li-rong Wang Wei liu Ming-Hang li Ying liu Xue-Fang Dai Guo-Dong liu xiao-Ming Zhang key laboratory of Reliability and Intelligence of Electrical Equipment School of Materials Science and Engineering ManufacturingHebei University of TechnologyTianjin 300130China

Materials featuring topological energy bands and nontrivial surface states hold significant promise in unlocking unprecedented opportunities for innovating electrocatalytic ***,it remains a challenge to realize superior topological catalysts which can carry both high catalytic activity and excellent catalytic ***,we propose that a family of Ni-based binary materials hosting fantasying topological conjunct-nodalpoint state and a large nontrivial energy window(NEWD)represents an ideal choice for such superior topological catalysts in hydrogen evolution *** presence of conjunct-nodal-points ensures long Fermi arcs on the surface,thereby enabling an extremely high catalytic *** NEWD plays a crucial role in stabilizing the high catalytic activity against external perturbations,such as strain and electron/hole *** roles for conjunctnodal-points and NEWD are substantiated by the observable weakening of catalytic performance during topological phase transitions,which result in the removal of the conjunct-nodal-points,NEWD and their corresponding long Fermi *** work unveils a hidden mechanism and opens a feasible route for developing superior quantum catalysts from novel topology point of view.

关键词： First-principles modeling Topological semimetal Nontrivial surface states Hydrogen evolution reaction