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Photochemical multicomponent transformation of acceptor-only diazoalkanes by merging their cycloaddition and carbene reactivities

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中国化学快报:英文版 2023年第9期34卷 138-142页

作者： Bao-Gui Cai Guo-Yong Xu Jun Xuan Anhui Province Key Laboratory of Chemistry for Inorganic/Organic Hybrid Functionalized Materials College of Chemistry&Chemical EngineeringAnhui UniversityHefei 230601China Key Laboratory of Structure and Functional Regulation of Hybrid Materials Ministry of EducationHefei 230601China institute of physical Science and Information Technology Anhui UniversityHefei 230601China

Herein,we report an efficient photochemical method for the synthesis of poly-substituted pyrazoles through a multicomponent reaction of acceptor-only diazoalkanes,alkynes,and solvents(cyclic ethers or nitriles).The key to this success was driven by the photolysis of acceptor-only diazoalkanes to form free carbene species and the fast in situ[3+2]-cycloaddition formation of nucleophilic N–H pyrazole *** work also serves as an entry to allow future reaction design on the combination of carbene reactivity of diazoalkanes with their other reaction modes.

关键词： Photochemical synthesis Multicomponent reaction Diazoalkanes Carbene Pyrazoles

The role of exercise in brain DNA damage

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Neural Regeneration Research 2020年第11期15卷 1981-1985页

作者： Thais Cereser Vilela Vanessa Moraes de Andrade Zsolt Radak Ricardo Aurino de Pinho Laboratory of Translational Biomedicine Graduate Program of Health SciencesUniversity of Southern Santa Catarina–UNESCCriciumaSCBrazil Research institute of Sport Science University of Physical EducationBudapestHungary Laboratory of Exercise Biochemistry in Health Graduate Program in Health SciencesSchool of MedicinePontificia Universidade Catolica do ParanaCuritibaPRBrazil

Cells are constantly subjected to cytotoxic and genotoxic insults resulting in the accumulation of unrepaired damaged DNA,which leads to neuronal *** this way,DNA damage has been implicated in the pathogenesis of neurological disorders,cancer,and *** factors,such as physical exercise,are neuroprotective and increase brain function by improving cognition,learning,and memory,in addition to regulating the cellular redox *** mechanisms are associated with the effects of exercise in the brain,such as reduced production of oxidants,up-regulation of antioxidant capacity,and a consequent decrease in nuclear DNA ***,physical exercise is a potential strategy for further DNA damage ***,the neuroplasticity molecules that respond to different aspects of physical exercise remain *** this review,we discuss the influence of exercise on DNA damage and adjacent mechanisms in the *** discuss the results of several studies that focus on the effects of physical exercise on brain DNA damage.

关键词： aerobic exercise apoptosis brain-derived neurotrophic factor brain DNA damage DNA repair neurodegenerative disease oxidative stress physical exercise strength exercise

Geometric phase helical PSF for simultaneous orientation and 3D localization microscopy

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Chinese Optics Letters 2024年第3期22卷 25-30页

作者：周勇壮张洪硕沈咏 Andrew R.Harvey 邹宏新 institute for Quantum Science and Technology College of ScienceNational University of Defense TechnologyChangsha 410073China Hunan Key Laboratory of Mechanism and Technology of Quantum Information Changsha 410073China School of Physics and Astronomy University of GlasgowGlasgow G128QQUK

The 3D location and dipole orientation of light emitters provide essential information in many biological,chemical,and physical *** acquisition of both information types typically requires pupil engineering for 3D localization and dual-channel polarization splitting for orientation *** we report a geometric phase helical point spread function for simultaneously estimating the 3D position and dipole orientation of point *** has a compact and simpler optical configuration compared to polarization-splitting techniques and yields achromatic phase modulation in contrast to pupil engineering based on dynamic phase,showing great potential for single-molecule orientation and localization microscopy.

关键词： PSF engineering geometric phase single-molecule orientation and localization microscopy

Formation of the front-gradient bandgap in the Ag doped CZTSe thin films and solar cells

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Journal of Energy Chemistry 2019年第8期28卷 188-196,I0007页

作者： Dongxiao Wang Jianyu Wu Xiyu Liu Li Wu Jianping Ao Wei Liu Yun Sun Yi Zhang institute of Photoelectronic Thin Film Devices and Technology and Tianjin Key Laboratory of Thin Film Devices and Technology Nankai UniversityTianjin 300350 China School of physical Science Nankai UniversityTianjin 300071 China

The graded bandgap of kesterite based absorber layer is an important way to achieve high efficiency solar cells. Incorporation of Ag into CZTSSe thin films can adjust the bandgap and thus reduce the VOC-deficit and improve the quality of crystallization. However, the distribution of Ag is difficult to control due to the quick diffusion of Ag under the high temperature. In this study, we achieve the front Ag-gradient in kesterite structured compound films by prealloying followed by selenization process at 550 °C. AgZn3,Ag3Sn, and Sn–Ag–Cu alloy phases were formed during prealloying stage at 250 °C. After prealloying process, Ag tends to distribute at the front surface of the ACZTSe thin films. Combining the results of experiment and SCAPS simulation, the significantly VOCimprovement of devices is ascribed to the formation of the front Ag-gradient bandgap structure in the absorber layer. This facile prealloying selenization process affords a feasible method to design the graded bandgap structure absorber layers, which will promote the fabrication of high efficient graded bandgap structure solar cells.

关键词： CZTSe solar cell Front Ag-gradient Elements distribution SCAPS simulation

Sexual function history taking in medicine

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World Journal of Methodology 2023年第2期13卷 26-28页

作者： Raktim Swarnakar Shiv Lal Yadav Department of physical Medicine and Rehabilitation All India Institute of Medical SciencesNew DelhiNew Delhi 110029India

Sexual history taking is important for the proper diagnosis and treatment of sexual *** is often neglected in a clinical setting and it is also underre-ported by patients due to stigma and *** we have described how we... 详细信息

关键词： Sexual function Sexual dysfunction History taking Medicine Rehabilitation medicine

Preparation and hydrogen permeation properties of BaCe_(0.95)Nd_(0.05)O_(3-δ) membranes

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Chinese Chemical Letters 2008年第10期19卷 1256-1259页

作者： Ming Ya Cai Hui Xia Luo Zhong Li Armin Feldhoff Jtirgen Caro Hai Hui Wang The Key Lab of Enhanced Heat Transfer and Energy Conservation of Chinese Ministry of Education School of Chemistry Engineering South China University of Technology Wushan Road Guangzhou 510640 China institute of physical Chemistry and Electrochemistry Leibniz University Hannover Callinstr. 3-3A D-30179 Hannover Received 31 March 2008 ＆ Chemical Germany

Dense mixed proton and electron conducting membrane made of BaCe0.95Nd0.05O3-δ （BCNd5） was prepared by pressing followed by sintering. X-ray diffraction （XRD） was used to characterize the phase structure of both the powder and the sintered membranes. The microstructure of the sintered membranes was studied by scanning electron microscopy （SEM）. Hydrogen permeation through the BCNd5 membrane was studied using a high temperature permeator. The hydrogen permeation fluxes under wet conditions are higher than those under dry conditions, which is due to H^＋ hopping via surface OH groups. At 925℃, a hydrogen permeation flux of 0.02 mL/min cm^2 was obtained under wet condition, which recommends BCNd5 as a potential material for hydrogen-selective membranes.

关键词： Hydrogen Mixed conductor Perovskite Membrane

Copper-Catalyzed Carbocyclization of Silyl Enol Ether Tethered Ynamides for Efficient and Practical Synthesis of 2-Azabicyclo[3.2.o] Compounds

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Chinese Journal of Chemistry 2020年第10期38卷 1086-1090页

作者： En-He Huang Zhi-Xin Zhang SiHan Ye Yang Bo Chen Wen-Feng Luo Peng Cheng Qian Long-Wu Ye State Key Llaboratory of physical Chemisty of Solid Surfaces and Key Laboratory for Chemical Biology of Fujian Province Cllege of Chemistry ano.Chemical EngineeringXiamen UniversityXiamenFujian 361005China institute of New Materials&Industry Technology College of Chemistry&Materials EngineeringWenzhou UniversityWenzhouhejiang 325035China State Key Laboratory of Organometollic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China

Summary of main observation and conclusion An efficient copper-catalyzed carbocyclization of silyl enol ether tethered ynamides has been developed,allowing rapid and practical construction of diverse 2-azabicyclo[3.2.0]compounds in generally good to excellent yields with broad substrate scope under mild reaction ***,this protocol not only constitutes a rare example of non-noble metal-catalyzed alkyne carbocyclization,but also represents a rare cyclization on the B-position ofπu-tethered *** possibility of asymmetric carbocyclization via kinetic resolution also emerges.

关键词： conditions. cyclization catalyzed

Quantitative detection of in vivo physical protein–protein interactions based on DNA sequence recognition

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分子细胞生物学报:英文版 2015年第4期7卷 383-386页

作者： Siwei Luo Yihua Jiang Zhi Liang Jiarui Wu Hefei National Laboratory for physical Sciences at Microscale and School of Life Science University of Science&Technology of ChinaHefeiChina Key Laboratory of Systems Biology Institute of Biochemistry and Cell BiologyShanghai Institutes for Biological SciencesChinese Academy of SciencesShanghaiChina School of Life Science and Technology Shanghai Tech UniversityShanghaiChina Shanghai Advanced Research institute Chinese Academy of SciencesShanghaiChina

Dear Editor,Understanding physical protein–protein interactions(PPIs)in vivo is amajor challenge in elucidating the molecular mechanisms in complex biological *** many approaches,such as the yeast two-hybrid(Y2H)assay,protein fragmentcomplementary assay(PCA),and fluorescence resonance energy transfer(FRET)assay,have been developed to assess the intensity of interaction of proteins in living cells,they have practical limitations for quantitation(Morell et al.,2009;Padilla-Parra and Tramier,2012;Stynen et al.,2012).Nucleic acid-based technologies,such as quantitative PCR(qPCR),DNA microarray,and deep sequencing,are probably most featured with quantification,high-throughput,and cost-effective for ***,new methods of detecting biomolecular interactions have been developed based on a strategy that labels target interactions using specific nucleic acid sequences(Soderberg et al.,2006;Yu et al.,2011;Zhu et al.,2013).

关键词： vivo complementary

Is the existence of a J/ψJ/ψbound state plausible?

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Science Bulletin 2021年第24期66卷 2462-2470,M0003页

作者： Xiang-Kun Dong Vadim Baru Feng-Kun Guo Christoph Hanhart Alexey Nefediev Bing-Song Zou CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China School of physical Sciences University of Chinese Academy of SciencesBeijing 100049China Institut für Theoretische Physik Ⅱ Ruhr-Universität BochumBochum D-44780Germany institute for Theoretical and Experimental Physics NRC“Kurchatov institute” Moscow 117218Russia institute for Advanced Simulation Institut für Kernphysik and Jülich Center for Hadron PhysicsForschungszentrum JülichJülich D-52425Germany P.N.Lebedev physical institute of the Russian Academy of Sciences Moscow 119991Russia Moscow institute of Physics and Technology Moscow 141700Russia School of Physics Central South UniversityChangsha 410083China

In a recent measurement LHCb reported pronounced structures in the J/ψJ/ψ*** of the various possible explanations of those is that they emerge from non-perturbative interactions of vector *** is thus important to understand whether it is possible to form a bound state of two charmonia interacting through the exchange of gluons,which hadronise into two pions at the longest *** this paper,we demonstrate that,given our current understanding of hadron-hadron interactions,the exchange of correlated light mesons(pions and kaons)is able to provide sizeable attraction to the di-J/ψsystem,and it is possible for two J/ψmesons to form a bound *** a side result we find from an analysis of the data for theψ/(2 S)J/ψππtransition including bothππand KK final state interactions an improved value for theψ(2 S)→J/ψtransition chromo-electric polarisability:|αψ(2 S)J/ψ|=(1.8±0.1)GeV-3,where the uncertainty also includes the one induced by the final state interactions.

关键词： Fully-charm tetraquark Hadronic molecule Exotic hadron Dispersion relation