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Paleomagnetic dating of the Cenjiawan Paleolithic site in the Nihewan Basin, northern china

Science china Earth Sciences 2006年第3期49卷 295-303页

作者： WANG Hongqiang1.2. DENG Chenglong1. {1. Rixiang1.& XIE Fei3 1. Paleomagnetism and Geochronology Laboratory (SKL-LE), Institute of Geology and Geophysics, Chinese Academy of Sci- ences, Beijing 1.002., china 2. {2. of the Earth Sciences and Resources, china university of Geosciences, Beijing 1.0083, china 3. Hebei Province Institute of Cultural Relics, Shijia{1.ang 050000, china 1. Paleomagnetism and Geochronology Laboratory (SKL-LE) Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China 2. {1. of the Earth Sciences and Resources China University of Geosciences Beijing 100083 China 3. Hebei Province Institute of Cultural Relics Shijiazhuang 050000 China

Rock magnetic and magnetostratigraphic investigations on a lacustrine sequence in the Nihewan Basin, northern china, which bears the Cenjiawan Paleolithic site, indicate that the dominant magnetic mineral and remanence carrier contained in the sediments is magnetite. While hematite co-exists with magnetite in some portions of the Cenjiawan sequence, where characteristic remanent magnetizations are carried by both magnetite and hematite. Measurements of anisotropy of magnetic susceptibility confirm that the Cenjiawan sequence has preserved the original sedimentary features and is suitable for magnetostratigraphic study. Paleomagnetic results indicate that the Cenjiawan Paleolithic site is formed just posterior to the Punaruu normal event, which is dated at about 1.1.Ma. Combined with the paleomagnetic results of the Donggutuo, Xiaochangliang and Majuangou sections, it is concluded that early humans were occupying the Nihewan Basin around 1.6, 1.3 and 1.1.Ma. This integrated result is significant to understanding the ability of migration and adaptation to the envi- ronment of early humans.

关键词： Nihewan Basin, Early Pleistocene, Cenjiawan, Paleolithic site, paleomagnetism.

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Study on frictional behavior of SiC_(f)/SiC composite clad tube clamping condition under nuclear irradiation

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Friction 2024年第5期12卷 919-938页

作者： Chenglong XIAO Liangliang SHEN Tianqi zhu Jianbo TANG Ximing XIE Xinyu {1. Jian XU Zhiying REN school of Mechanical Engineering Zhejiang University of TechnologyHangzhou310023China Engineering Laboratory of Advanced Energy Materials Ningbo Institute of Material Technology and EngineeringChinese Academy of SciencesNingbo315201China State Key Laboratory of Fine Chemicals Liaoning High-Performance Polymer Engineering Research CenterSchool of Chemical EngineeringDalian University of TechnologyDalian116024China school of Mechanical Engineering and Automation Fuzhou UniversityFuzhou350116China school of Computer Science and Technology Shandong UniversityQingdao266237China Aviation Industry Corporation of china Ltd.Beijing100028China

Silicon carbide fiber reinforced silicon carbide matrix(SiC_(f)/SiC)composite is the key cladding material of nuclear fuel,which determines the safety and reliability of nuclear fuel storage and *** replacement of its storage and transportation scenario needs to be completed by the manipulator,but the application of SiC_(f)/SiC wear,fracture,and nuclear leakage in the snatching process of brittle-flexible-rigid contact in the irradiation environment has been seriously restricted due to unclear understanding of the damage ***,the effects of irradiation dose and clamping load on the friction characteristics of the contact interface between SiC_(f)/SiC clad tube are studied in this paper,and the effects of irradiation parameters and clamping force on the static friction coefficient of the contact interface between the clad tube and flexible nitrile are *** on the Greenwood-Williamson tribological model,a numerical model of the shape and structure of the contact micro-convex at the micro-scale of the clamping interface is constructed by introducing the multi-surface integral,and finally verified by *** research results show that there is a unique“Irradiation suppression zone”under the clamping condition of SiC_(f)/SiC cladding tube under the nuclear irradiation environment,and the growth of static friction coefficient slows down until stagnates after irradiation reaches a certain extent(600 kGy),and there will be a decline when the irradiation dose continues to increase,among which the clamping force of 1..2.N within the irradiation interval of 1.000 kGy can meet the safety of nuclear environment *** results of this paper can provide an important theoretical basis and application guidance for the safe operation of SiC_(f)/SiC cladding tubes in the storage and transportation clamping process.

关键词： SiC_(f)/SiC Clad tube nuclear irradiation conditions Greenwood-Williamson tribological model multi-surface integral

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Melittin analog p5RHH enhances recombinant adeno-associated virus transduction efficiency

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Journal of Integrative Medicine 2024年第1期22卷 72-82页

作者： Jing-shun Meng yun He Heng-bin Yang Li-{1. Zhou Si-yuan Wang Xi-lin Feng Omar Yahya Al-shargi Xiao-min Yu Li-qing {2. Chang-quan Ling Shanghai university of Traditional Chinese Medicine Shanghai 201203China Oncology Department of Traditional Chinese Medicine Changhai HospitalNaval Medical UniversityShanghai 200433China Faculty of Traditional Chinese Medicine Naval Medical UniversityShanghai 200043China State Key Laboratory of Genetic Engineering and Engineering Research Center of Gene Technology(Ministry of Education) School of Life SciencesZhongshan HospitalFudan UniversityShanghai 200438China Yantai Fuheng Biological Technology Co. Ltd.YantaiShandong Province 264006China. Department of Clinical Laboratory the First Affiliated Hospital of Wenzhou Medical UniversityWenzhou 325000Zhejiang ProvinceChina

Objective Melittin and its derivatives have been characterized to establish effective gene delivery *** capability of facilitating endosomal release enhances the nanoparticles-based gene ***,little investigation has been conducted to explore its potential application in the context of viral *** Various melittin-derived peptides were inserted into the loop VIII of the capsid proteins of recombinant adeno-associated virus *** vectors carrying either gfp or fluc genes were subjected to qPCR assays and transduction assays of HEK2.3T cells to investigate the efficiency of vector production and gene *** addition,the ability of a specific p5RHH-rAAV vector to deliver genes was examined through in vitro transduction of different cultured cells and in vivo tail vein administration to C57BL/6 ***,the intricate details of the vector-mediated transduction mechanisms were revealed by specific pharmacological inhibitors of every stage of the rAAV2.intracellular life *** A total of 76 melittin-related peptides were compiled from existing *** them,cMA2.Melt1.,p5RHH and aAR3 were found to significantly enhance the gene delivery efficiency of rAAV2.*** p5RHH-rAAV2.vectors efficiently transduced not only rAAV-potent cell lines but also cell lines previously considered resistant to ***,bafilomycin A1.a vacuolar endosome acidification inhibitor,completely inhibited the transgene expression mediated by the p5RHH-rAAV2.*** importantly,p5RHH-rAAV8 vectors also demonstrated increased hepatic transduction in vivo in C57BL/6 *** The incorporation of melittin analogues into the rAAV capsids results in a significant improvement in rAAV-mediated transgene *** further modifications remain an area of interest,our studies have substantially broadened the pharmacological prospects of melittin in the context of viral vector-mediated gene delivery.

关键词： Melittin Recombinant adeno-associated virus Capsid engineering Transduction efficiency

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Azobenzene-based ultrathin peptoid nanoribbons for the potential on highly efficient artificial light-harvesting

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Science china Chemistry 2024年第5期67卷 1680-1686页

作者： Zichao Sun Lingrong zhu Jingze Liu {1. Liu Pengchao Wu Pengliang Sui Haibao Jin Shaoliang Lin Shanghai Key Laboratory of Advance Polymeric Materials Frontiers Science Center for Materiobiology and Dynamic ChemistrySchool of Materials Science and EngineeringEast China University of Science and TechnologyShanghai 200237China

The development of artificial light-harvesting systems based on long-range ordered ultrathin organic nanomaterials(i.e., below3 nm), which were assembled from stimuli-responsive sequence-controlled biomimetic polymers, remains challenging. Herein,we report the self-assembly of azobenzene-containing amphiphilic ternary alternating peptoids to construct photo-responsive ultrathin peptoids nanoribbons(UTPNRs) with a thickness of ~2.3 nm and the length in several micrometers. The pendants hydrophobic conjugate stacking mechanism explained the formation of one-dimensional ultrathin nanostructures, whose thickness was highly dependent on the length of side groups. The photo-isomerization of azobenzene moiety endowed the aggregates with a reversible morphology transformation from UTPNRs to spherical micelles(46.5 nm), upon the alternative irradiation with ultraviolet and visible light. Donor of 4-(2.hydroxyethylamino)-7-nitro-2.1.3-benzoxadiazole(NBD) and acceptor of rhodamine B(RB) were introduced onto the hydrophobic and hydrophilic regions, respectively, to generate photocontrollable artificial light-harvesting systems. Compared with the spheres-based systems, the obtained NBD-UTPNRs@RB composite proved a higher energy transfer efficiency(90.6%) and a lower requirement of RB acceptors in water. A proof-ofconcept use as fluorescent writable ink demonstrated the potential of UTPNRs on information encryption.

关键词： azobenzene-based peptoid ultrathin nanoribbon photo-responsive light-harvesting information encryption

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Multifunctional AlPO_(4)reconstructed LiMn_(2.O_(4)surface for electrochemical lithium extraction from brine

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Journal of Energy Chemistry 2024年第2期89卷 410-421,I0010页

作者： Jun Gu Linlin Chen Xiaowei Li Guiling Luo Linjing fan Yanhong Chao Haiyan Ji Wenshuai {1. school of Materials Science and Engineering Jiangsu UniversityZhenjiang 212013JiangsuChina school of Chemistry and Chemical Engineering Jiangsu UniversityZhenjiang 212013JiangsuChina College of Science State Key Laboratory of Heavy Oil ProcessingChina University of Petroleum-BeijingBeijing 102249China school of the Environment and Safety Engineering Jiangsu UniversityZhenjiang 212013JiangsuChina

LiMn_(2.O_(4)(LMO)electrochemical lithium-ion pump has gained widespread attention due to its green,high efficiency,and low energy consumption in selectively extracting lithium from ***,collapse of crystal structure and loss of lithium extraction capacity caused by Mn dissolution loss limits its industrialized ***,a multifunctional coating was developed by depositing amorphous AlPO_(4)on the surface of LMO using sol-gel *** characterization and electrochemical performance test provided insights into the mechanism of Li^(+)embedment and de-embedment and revealed that multifunctional AlPO_(4)can reconstruct the physical and chemical state of LMO surface to improve the interface hydrophilicity,promote the transport of Li^(+),strengthen cycle ***,after 2. cycles,the capacity retention rate of 0.5AP-LMO reached 93.6%with only 0.1.7%Mn dissolution *** average Li^(+)release capacity of 0.5AP-LMO//Ag system in simulated brine is 2..77 mg/(g h),which is 90.4%higher than ***,even in the more complex Zabuye real brine,0.5AP-LMO//Ag can still maintain excellent lithium extraction *** results indicate that the 0.5AP-LMO//Ag lithium-ion pump shows promising potential as a Li^(+)selective extraction system.

关键词： LiMn_(2.O_(4) Multifunctional AlPO_(4)coating Li^(+)embedment and de-embedment mechanism Stability Hydrophilicity Various solution

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Persistence of bounded solutions to degenerate Sobolev-Galpern equations

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Science china {1. 2010年第11期53卷 2831-2846页

作者： zhu ChangRong1.& ZHANG WeiNian{1. 1.2} of {{1., Chongqing university, Chongqing 400044, china {1.angtze Center of {{1. and Department of {{1., Sichuan university, Chengdu 61.064, china 1. school of {1. Chongqing University Chongqing 400044 China2. Yangtze Center of Mathematics and Department of Mathematics Sichuan University Chengdu 610064 China

In this paper the persistence of bounded solutions to degenerate evolution equations of Sobolev-Galpern type is discussed. In order to define the evolution operator well, we study the existence and uniqueness of solutions to its linear form. On this basis we discuss exponential dichotomies of the evolution operator and give the Fredholm alternative result for bounded solutions of nonhomogeneous linear degenerate equations. This result enables us to give a condition for the persistence of bounded solutions of a general degenerate nonlinear autonomous equation under a nonautonomous perturbation.

关键词： degenerate evolution equation Sobolev-Galpern type boundedness Fredholm alternative exponential dichotomy

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Carbon coated LaFe_(0.92.Pd_(0.08)O_(3) composites for catalytic transfer hydrogenation:Balance in the ability of substrates adsorption and conversion

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Nano Research 2024年第5期17卷 3724-3732页

作者： Bowen Wang Nan Zhang ping Xiao Jian Zhang Sónia A.C.Carabineiro Junjiang {1. hubei Key Laboratory of Biomass Fibers and Eco-dyeing&Finishing College of Chemistry and Chemical EngineeringWuhan Textile UniversityWuhan 430200China College of Chemistry and Materials Engineering Wenzhou UniversityWenzhou 325035China LAQV-REQUIMTE Department of ChemistryNOVA School of Science and TechnologyUniversidade NOVA de LisboaLargo da Torre2829-516 CaparicaPortugal

Catalytic transfer hydrogenation(CTH)is a green and efficient pathway for selective hydrogenation of unsaturated aldehydes and ***,managing the abilities of solid catalysts to adsorb substrates and to convert them into desired products is a challenging ***,we report the synthesis of carbon coated LaFe_(0.92.Pd_(0.08)O_(3) composites(LFPO-8@C)for CTH of benzaldehyde(BzH)into benzyl alcohol(BzOH),using isopropanol(IPA)as hydrogen *** coating with carbon improves the ability to adsorb/transfer reactants from solution to active sites,and the do{1. of Pd2.at Fe3+site strengthens the ability of LaFeO_(3) to convert BzH into BzOH.A balanced point between them(i.e.,abilities to adsorb BzH and to convert BzH into BzOH)is obtained at LFPO-8@C,which exhibits a BzOH formation rate of 3.88 mmol·gcat^(-1.·h^(-1. at 1.0℃ for 3 h,which is 1.50 and 2.72.times faster than those of LFPO-8 and LaFeO_(3)@C.A reaction mechanism is proposed,in which the acidic sites(e.g.,Fe^(4+),oxygen vacancy)are used for the activation of C=O bond of BzH and O-H bond of IPA,and the basic sites(e.g.,lattice oxygen)for the activation ofα-H(O-H)bond of IPA.

关键词： LaFe_(0.92.Pd_(0.08)O_(3) porous carbon catalytic transfer hydrogenation isopropanol reaction mechanism

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Two-dimensional bimetallic selenium-containing metal-organic frameworks and their calcinated derivatives as electrocatalysts for overall water splitting

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Frontiers in Energy 2024年第3期18卷 378-389页

作者： Zhao-ting SHANG Tang-ming LI Bing-qian HU Min LIU Wang-ting LU fan YU {1. ZHENG Key Laboratory of Optoelectronic Chemical Materials and Devices of Ministry of Education College of Optoelectronic Materials and TechnologyJianghan UniversityWuhan 430056China Institute of New Energy Materials and Engineering School of Materials Science and EngineeringFuzhou UniversityFuzhou 350108China Department of Chemical Engineering University of WaterlooWaterlooOntario N2L 3G1Canada

The use of two-dimensional(2.)layered metal-organic frameworks(MOFs)as self-sacrificial templates has been proven to be a successful method to create high-efficiency Selenium(Se)-containing electrocatalysts for overall water ***,two strategies are then utilized to introduce Se element into the Co–Fe MOF,one being the etching of as-prepared MOF by SeO_(2. solution,and the other,the replacing of SCN−with SeCN−as the construction *** electrochemical activity of the pristine 2. MOF and their calcinated derivatives for catalyzing the hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)is evaluated and further *** is found that the effect of introducing Se on improving electrochemical catalytic activity is significant for the HER ***,the calcinated derivative in the replacing method exhibits an overpotential of 2.5 mV for HER and 2.0 mV for OER at a current density of 1. mA/*** comparing the two methods of introducing Se element into MOF,similar electrocatalytic activity can be achieved on the their calcinated *** high electrochemical performance of 2. CoFe-MOF derivatives may be resulted from the unique 2. hierarchical porous structure and strong synergistic effect between different components in the material.

关键词： 2. MOF selenium(Se)-containing materials hydrogen evolution reaction(HER) oxygen evolution reaction(OER)

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A new method of discovering new meteor showers from the IMO single-station video meteor database

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Science china(Physics,Mechanics & Astronomy) 2008年第8期51卷 1170-1178页

作者： LI Jun1.2.& {1. Jin3 1.No.2.Middle school of Beijing,Beijing 1.001.,{2. 2.school of Journalism and Communication,Tsinghua university,Beijing 1.0084,{2. 3 Beijing Planterium,Beijing 1.0044,{2. 1. No.2.Middle {1. of Beijing Beijing 100010 China 2. {1. of Journalism and Communication Tsinghua University Beijing 100084 China 3. Beijing Planterium Beijing 100044 China

It has been found that unknown meteor showers could be efficiently discovered from the single station video meteor database of the International Meteor Organization(IMO) by assuming the geocentric velocity and adjusting it within the dynamically permitted range. The mean geocentric velocities of new meteor showers can be obtained,as well as the coordinates of the radiants. The activity period and maximum time can also be obtained if there are sufficient shower meteors. All single station video meteor observations between February 1. and 1.(from 2.00 to 2.05) in IMO's database are processed with this method. As a result,two new meteor showers,one near RA=2.5.1.°,Dec=41.82. in Hercules and the other near RA=2.3.03°,Dec=1..04° in Serpenids,are discovered. Some dynamical characteristics of the new meteor showers are also determined. Considering the random nature on the selection of period in this work,it is expected that there are some more potential new meteor showers in IMO's video database.

关键词： single-station video meteor database the process of single-station video meteor database discovery of new meteor showers

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Multi-dimensional project management models for mega-construction companies and their applications

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Science china(Technological Sciences) 2011年第S1期54卷 118-124页

作者： LIN ZhengHang 1,2.QIANG MaoShan 1,2.TANG WenZhe 1,2.fan QiXiang 3 &LIU Qiang 4 1 Institute of Project Management and Construction Technology,Tsinghua university,Beijing 100084,{2. 2.State Key Laboratory of Hydraulic and Engineering,Tsinghua university,Beijing 100084,{2. 3 china Three Gorges Corporation,Yichang 443002.{2. 4 school of Software,Tsinghua university,Beijing 100084,{2. 1. Institute of Project Management and Construction Technology Tsinghua University Beijing 100084 China2. State Key Laboratory of Hydraulic and Engineering Tsinghua University Beijing 100084 China3. China Three Gorges Corporation Yichang 443002 China4. School of Software Tsinghua University Beijing 100084 China

china is undertaking an increasing number of mega-infrastructure projects along with its rapid economic *** participants in these projects,understand how to adapt the proper and efficient management strategies is *** this paper,we propose three distinct models for companies under various background and management requirements,based on sophisticated data analysis and model ***,we successfully committed these models with hydropower development projects and achieved a great progress in enhancing management efficiency.

关键词： project management models mega-construction companies applications hydropower development companies

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