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On the Possibility to Construct Gravitational Eye

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Communications in Theoretical Physics 2007年第5期47卷 851-860页

作者： chen ying-Tian Department of Astronomy and Applied Physics University of Science and Technology of China Hefei 230026 China Institute of Theoretical Physics the Chinese Academy of Sciences Beijing 100080 China Cavendish Laboratory University of Cambridge Cambridge U.K.

The possibility of modifying a conventional Cavendish torsion pendulum into a half-armed pendulum oscillator to measure the horizontal gravitational acceleration is discussed. A new kind of gravitational detector, gravieye, as we named, can be made by a proper combination of such oscillators to ＂see＂ remote objects and to be used, e.g. to detect the movement of huge mass at a long distance.

关键词： gravitational eye Cavandish torsion pendulum gravitational experiment gravieye

The role of m^(6)A RNA methylation in autoimmune diseases: Novel therapeutic opportunities

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Genes & Diseases 2024年第1期11卷 252-267页

作者： Yunan shan Wei chen Yanbin Li The First Clinical Medical College Shandong University of Traditional Chinese MedicineJinanShandong 250013China Department of Neurology The First Affiliated Hospital of Shandong First Medical University&Shandong Provincial Qjanfoshan HospitalShandong Institute of NeuroimmunologyShandong Key Laboratory of Rheumatic Disease and Translational MedicineJinanShandong 250013China Department of Gastroenterology Shanghai Sixth People's Hospital Affiliated to Shanghai Jiao Tong University School of MedicineShanghai 200233China

N6-methyladenosine m^(6)A modifications,as one of the most common forms of in-ternal RNA chemical modifications in eukaryotic cells,have gained increasing attention in recent *** m^(6)A RNA modifications exert various crucial roles in various biological pro-cesses,such as embryonic development,neurogenesis,circadian rhythms,and *** advances have highlighted that m^(6)A RNA modification plays an important role in im-mune response,especially in the initiation and progression of autoimmune *** this re-view,we summarized the regulatory mechanisms of m^(6)A methylation and its biological functions in the immune system and mainly focused on recent progress in research on the po-tential role of m^(6)A RNA methylation in the pathogenesis of autoimmune diseases,thus providing possible biomarkers and potential targets for the prevention and treatment of auto-immunediseases.

关键词： Adaptive immunity Autoimmune diseases Innate immunity Immune response m^(6)A RNA methylation

Numerical investigation of the effect of geosynthetic clay liner chemical incompatibility on flow and contaminant transport through a defective composite liner

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2023年第7期24卷 557-568页

作者： Shiyuan YAO Yuchao LI shan TONG Guannian chen Yunmin chen MOE Key Laboratory of Soft Soils and Geoenvironmental Engineering Department of Civil EngineeringZhejiang UniversityHangzhou 310058 China School of Civil&Environmental Engineering and Geography Science Ningbo UniversityNingbo 315211China Ningbo ZCONE High-tech Co. Ltd.Ningbo 315000China

A composite liner consisting of a geomembrane(GMB)and a geosynthetic clay liner(GCL)can be compromised by inorganic contaminants because of a defective *** the composite liner with defective GMB is exposed to aggressive leachate conditions,the neglect of the chemical incompatibility of the GCL can potentially result in an underestimation of the leakage rate and flux through the composite *** paper proposed a numerical investigation on the effect of chemical incompatibility of GCL on the barrier performance of the composite liner with hole *** cases with leachate solutions having varied cation valencies and ionic strengths were analyzed,in which the hydraulic conductivity of GCL was *** the effect of the chemical incompatibility of GCL and the mechanisms were *** incompatibility of GCL resulted in significant increases in leakage rate and flux through the composite liner by factors of up to 4.9 and 5.0,*** incompatibility-affected area in GCL is located within 0.1 m from the center of the hole in the *** coupled increase in the hydraulic conductivity of GCL and pore water concentration impacts the flux and leakage in a short period of *** GCL chemical incompatibility considered,advection may dominate the contaminant transport through GCL.

关键词： Geosvnthetic clay liner(GCL) Chemical incompatibility Leakage Contaminant transport Hvdraulic conductivity

A Weak∞-Functor in Morse Theory

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Acta Mathematica Sinica,English Series 2024年第11期40卷 2571-2614页

作者： shan Zhong SUN chen Xi WANG Department of Mathematics Capital Normal UniversityBeijing100048P.R.China Academy for Multidisciplinary Studies Capital Normal UniversityBeijing100048P.R.China

In the spirit of Morse homology initiated by Witten and Floer,we construct two∞-categories A and *** weak one A comes out of the Morse-Smale pairs and their higher homotopies,and the strict one B concerns the chain complexes of the Morse *** on the boundary structures of the compactified moduli space of gradient flow lines of Morse functions with parameters,we build up a weak∞-functor F:A→*** algebraic structures behind Morse homology are revealed with the perspective of defects in topological quantum field theory.

关键词： Morse function moduli space of gradient flow lines compactifications weak n/∞-category higher morphism homotopy

Strong　earthquake　activity　all　over　the　world　and　strong-moderate　earthquake　activity　within　and　nea

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Acta Seismologica Sinica(English Edition) 1998年第4期11卷 515-516页

作者： Pei-shan chen Institute of Geophysics China Seismological Bureau Beijing China

Ｓｔｒｏｎｇｅａｒｔｈｑｕａｋｅａｃｔｉｖｉｔｙａｌｌｏｖｅｒｔｈｅｗｏｒｌｄａｎｄｓｔｒｏｎｇ－ｍｏｄｅｒａｔｅｅａｒｔｈｑｕａｋｅａｃｔｉｖｉｔｙｗｉｔｈｉｎａｎｄｎｅａｒＣｈｉｎａ（Ｆｅｂｒｕａｒｙ，１９９８－... 详细信息

Ｓｔｒｏｎｇｅａｒｔｈｑｕａｋｅａｃｔｉｖｉｔｙａｌｌｏｖｅｒｔｈｅｗｏｒｌｄａｎｄｓｔｒｏｎｇ－ｍｏｄｅｒａｔｅｅａｒｔｈｑｕａｋｅａｃｔｉｖｉｔｙｗｉｔｈｉｎａｎｄｎｅａｒＣｈｉｎａ（Ｆｅｂｒｕａｒｙ，１９９８－Ｍａｒｃｈ，１９９８）ＰＥＩ－ＳＨ...

关键词： over all the world activity Strong

Vortex analysis of water flow through gates by different vortex identification methods

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Journal of Hydrodynamics 2023年第1期35卷 112-124页

作者： Chun-ying Shen Rui-guo Yang shan Qing Shi-hua He Faculty of Electrical Power Engineering Kunming University of Science and TechnologyKunming650500China

The pre-gate suction vortex,gate-bottom-edge transverse vortex,gate-slot vertical vortex,and downstream-of-gate return vortex are important factors affecting the flow instability of flat gates,which may lead to fatigue failure in severe *** study used the volume of fluid(VOF)model and large eddy simulation(LES)method to accurately capture the transient turbulence characteristics of flow under different water flow conditions and reveal the flow field and vortex *** Q—criterion,Omega(Ω)method,and latest third-generation Liutex vortex identification method were used to analyze and compare the pre-gate suction vortex,gate-slot vertical vortex,and downstream-of-gate return vortex,focusing on the ability of each vortex identification method to capture the flow field information and vortex *** results reveal that theΩmethod and Liutex method are less dependent on the threshold value,and the Liutex method captures a wide range of pre-gate *** flow conditions cause changes in the vortex structure of over-gate *** the relative opening of the gate is smaller,the intensity of the vortices in the flow field around the gate is greater,the return vortices downstream of the gate are more disordered,and the vortex changes are more violent,which in turn affects the efficient and stable operation of the gate.

关键词： Vortex features vortex identification methods Liutex Ωmethod Q-criterion large eddy simulation(LES)

Confinement and the global SU(3)color symmetry

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Chinese Physics C 2021年第4期45卷 1-5页

作者： ying chen Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China School of Physics University of Chinese Academy of SciencesBeijing 100049China

The global SU(3)color symmetry and its physical consequences are *** Nother current is actually governed by the conserved matter current of color charges if the color field generated by this charge is properly *** color field strength of a charge can have a uniform part due to the nontrivial QCD vacuum field and the nonzero gluon condensate,which implies that the self-energy of a system with a net color charge is infinite and,therefore,cannot exist as a free *** is precisely what color confinement ***,the Cornell type potential with the feature of Casimir scaling is derived for a color singlet system composed of a static color charge and an *** uniform color field also implies that a hadron has a minimal size and minimal ***,the global S U(3)color symmetry requires that the minimal irreducible color singlet systems can only be qq,qqq,gg,ggg,qqg,qqqg,qqqg,etc.,therefore a multi-quark system can only exist as a molecular configuration if there are no other binding mechanisms.

关键词： confinement global SU(3)color symmetry static potential

Plant Terpenoids： Biosynthesis and Ecological Functions

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Journal of Integrative Plant Biology 2007年第2期49卷 179-186页

作者： Ai-Xia cheng Yong-Gen Lou ying-Bo Mao shan Lu Ling-Jian Wang Xiao-Ya chen National Key Laboratory of Plant Molecular Genetics Institute of Plant Physiology and Ecology Shanghai Institutes for Biological Sciences the Chinese Academy of Sciences Shanghai 200032 China Institute of Insect Sciences Zhejiang University Hangzhou 310029 China

Among plant secondary metabolites terpenolds are a structurally most diverse group; they function as phytoalexins In plant direct defense, or as signals In Indirect defense responses which involves herbivores and their natural enemies. In recent years, more and more attention has been paid to the Investigation of the ecological role of plant terpenolds. The biosynthesis pathways of monoterpenes, sesquiterpenes, and diterpenes Include the synthesis of C5 precursor isopentenyl diphosphate （IPP） and Its allylic isomer dlmethylallyl dlphosphate （DMAPP）, the synthesis of the immediate diphosphate precursors, and the formation of the diverse terpenoids. Terpene synthases （TPSs） play a key role In volatile terpene synthesis. By expression of the TPS genes, significant achievements have been made on metabolic engineering to Increase terpenoid production. This review mainly summarizes the recent research progress In elucidating the ecological role of terpenoids and characterization of the enzymes Involved in the terpenold biosynthesis. Spatial and temporal regulations of terpenoids metabolism are also discussed.

关键词： chemical ecology metabolism regulation plant terpenoids terpene synthase.

Defect passivation of CsPbI2Br perovskites through Zn（Ⅱ） doping:toward efficient and stable solar cells

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Science China Chemistry 2019年第8期62卷 1044-1050页

作者： Jiajun Lu shan-Ci chen Qingdong Zheng State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China University of Chinese Academy of Sciences Beijing 100049China School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210China shanghai Institute of Ceramics Chinese Academy of SciencesShanghai 200050China

Defect passivation is an important strategy to achieve perovskite solar cells(PVSCs) with enhanced power conversion efficiencies(PCEs) and improved stability because the trap states induced by defects in the interfaces and grain boundaries of perovskites are harmful to both large open circuit voltage and high photocurrent of devices. Here, zinc cations(Zn^2+) were used as a dopant to passivate defects of the CsPbI2Br perovskite leading to Zn^2+-doped CsPbI2Br film with fewer trap states, improved charge transportation, and enhanced light-harvesting ability. Thus, the best-performance PVSC based on CsPbI2 Br with the optimal Zn^2+doping shows a higher PCE of 12.16% with a larger open-circuit voltage(VOC) of 1.236 V, an improved shortcircuit current(JSC) of 15.61 mA cm^-2 in comparison with the control device based on the pure CsPbI2Br which exhibits a PCE of 10.21% with a VOCof 1.123 V, a JSCof 13.27 mA cm^-2. Time-resolved photoluminescence results show that the Zn^2+doping leads to perovskite film with extended photoluminescence lifetime which means a longer diffusion length and subsequently enhanced photocurrent and open circuit voltage. This work provides a simple strategy to boost the performance of PVSCs through Zn^2+doping.

关键词： CsPbI2Br perovskites defect passivation Zn(Ⅱ) doping all-inorganic perovskite solar cells power conversion efficiency