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Mass extinctions, their causes and consequences: an interview with Douglas *** and Shuzhong Shen

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National Science Review 2024年第1期11卷 66-70页

作者： Shucheng Xie state key laboratory of Biogeology and Environmental Geology China University of Geosciences at Wuhan

‘Mass extinctions’ have been a hot topic for several decades. What triggers a mass extinction? How does a mass extinction impact the evolution of life? How does our ecosystem recover after a mass extinction? These questions attracted the interest of both scientists and the public *** spoke to two renowned researchers in the field of mass extinctions: Prof. Douglas H. Erwin from the National Museum of Natural History of the USA, and Prof. Shuzhong Shen from Nanjing University, China.

关键词： Stratigraphy

Copper-catalyzed enantioselective desymmetrizing C(sp^(2))-H functionalization of azide-ynamides via α-imino copper carbenes

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Science China Chemistry 2024年第9期67卷 2982-2988页

作者： En-He Huang Li-Gao Liu You-Wei Yin Hao-Xuan Dong Ji-Jia Zhou Xin Lu Bo Zhou Long-Wu Ye key laboratory for Chemical Biology of Fujian Province and state key laboratory of Physical Chemistry of Solid Surfaces College of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China state key laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China

α-Imino metal carbenes are versatile intermediates in organic synthesis,and have broad applications in the assembly of divergent ***,the catalytic enantioselective desymmetrization based onα-imino metal carbenes has not been developed to ***,we disclose an enantioselective desymmetrizing C(sp^(2))-H functionalization of azide-ynamides viaα-imino copper carbenes,leading to the efficient assembly of divergent chiral indoloazepines in generally moderate to excellent yields with high ***,this reaction represents the first enantioselective desymmetrization based onα-imino metal *** synthetic transformations and biological tests show the potential utility of this ***,computational studies are employed to elucidate the reaction mechanism and the origin of enantioselectivity.

关键词： enantioselective desymmetrization metal carbenes copper catalysis nitrene transfer alkynes

Discovery of proqodine A derivatives with antitumor activity targeting NAD(P)H:quinone oxidoreductase 1 and nicotinamide phosphoribosyltransferase

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Chinese Journal of Natural Medicines 2024年第1期22卷 75-88页

作者： SONG Jiangzhou ZOU Guiqing ZHAO Zhou ZHU Ya XUE Jiayu AO Lanjia SUN Huiyong HAO Haiping ZHANG Bo XU Xiaowei state key laboratory of Natural Medicines Key Lab of Drug Metabolism and PharmacokineticsChina Pharmaceutical UniversityNanjing 210009China state key laboratory of Natural Medicines China Pharmaceutical UniversityNanjing 210009China

NAD(P)H:quinone oxidoreductase 1(NQO1)is a flavin protease highly expressed in various cancer ***1 catalyzes a futile redox cycle in substrates,leading to substantial reactive oxygen species(ROS)*** ROS generation results in extensive DNA damage and elevated poly(ADP-ribose)polymerase 1(PARP1)-mediated consumption of nicotinamide adenine dinucleotide(NAD^(+)),ultimately causing cell *** phosphoribosyltransferase(NAMPT),the rate-limiting enzyme in the NAD^(+)salvage synthesis pathway,emerges as a critical target in cancer *** concurrent inhibition of NQO1 and NAMPT triggers hyperactivation of PARP1 and intensive NAD+*** this study,we designed,synthesized,and assessed a novel series of proqodine A derivatives targeting both NQO1 and *** these,compound T8 demonstrated potent antitumor ***,T8 selectively inhibited the proliferation of MCF-7 cells and induced apoptosis through mechanisms dependent on both NQO1 and *** discovery offers a promising new molecular entity for advancing anticancer research.

关键词： NQO1 ROS NAMPT NAD^(+) T8

Improving actionable warning identification via the refined warning-inducing context representation

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Science China(Information Sciences) 2024年第5期67卷 321-322页

作者： Xiuting GE Chunrong FANG Xuanye LI Quanjun ZHANG Jia LIU Zhihong ZHAO Zhenyu CHEN state key laboratory for Novel Software Technology Nanjing University

Static analysis tools(SATs) have shown potential ability in software quality assurance [1]. However, SATs report an overwhelming number of warnings, where most warnings are unactionable ones(i.e., warnings that are not acted on or fixed by developers). It is not a trivial task for developers to find actionable warnings(i.e., warnings that are acted on and fixed by developers) in all reported warnings. Hence,the excessive unactionable warnings seriously impede the usability of SATs [2].

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Comparative analysis of frictional behavior and mechanism of molybdenum ditelluride with different structures

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Friction 2024年第1期12卷 110-119页

作者： Lina ZHANG Xinfeng TAN Jianguo JIAO Dan GUO Jianbin LUO state key laboratory of Tribology in Advanced Equipment Tsinghua UniversityBeijing 100084China

Two-dimensional(2D)transition metal dichalcogenides(TMDCs)have layered structures with excellent tribological *** the energy difference between hexagonal-molybdenum ditelluride(2H-MoTe_(2))and distorted octahedral-molybdenum ditelluride(1T′-MoTe_(2))is very small among the transition metal dichalcogenides(TMDCs),MoTe_(2) becomes one of the most promising candidates for phase *** our experiment,we found that the friction force and friction coefficient(COF)of 2H-MoTe_(2) were an order of magnitude smaller than those of 1T′-MoTe_(2) by the atomic force microscope(AFM)*** friction difference between 1T′-MoTe_(2) and 2H-MoTe_(2) was further verified in molecular dynamics(MD)*** density functional theory(DFT)calculations suggest that the friction contrast is related to the difference in sliding energy barrier of the potential energy surface(PES)for a tip sliding across the *** PES obtained from the DFT calculation indicates that the maximum energy barrier and the minimum energy path(MEP)energy barrier of 2H-MoTe_(2) are both smaller than those of 1T′-MoTe_(2),which means that less energy needs to be dissipated during the sliding *** difference in energy barrier of the PES could be ascribed to its larger interlayer spacing and weaker Mo–Te interatomic interactions within the layers of 2H-MoTe_(2) than those of 1T′-MoTe_(2).The obvious friction difference between 1T′-MoTe_(2) and 2H-MoTe_(2) not only provides a new non-destructive means to detect the phase transition by the AFM,but also provides a possibility to tune friction by controlling the phase transition,which has the potential to be applied in extreme environments such as space lubrication.

关键词： friction two-dimensional(2D)materials distorted octahedral-molybdenum ditelluride(1T′-MoTe_(2)) hexagonal-molybdenum ditelluride(2H-MoTe_(2)) phase transition

Crystallization management of CsPbI2Br perovskites by PbAc2-incorporated twice spin-coating process for efficient and stable CsPbI2Br perovskite solar cells

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Journal of Energy Chemistry 2024年第10期97卷 419-428页

作者： Yu Liu Kun Lang Huifang Han Huijing Liu Yao Fu Pengchen Zou Yinhui Lyu Jia Xu Jianxi Yao state key laboratory of Alternate Electrical Power System with Renewable Energy Sources Beijing Key Laboratory of Energy Safety and Clean Utilization North China Electric Power University

CsPbI2Br perovskite solar cell has been extensively studied due to its exceptional thermal stability and relatively stable perovskite phase ***,the presence of bromine leads to a rapid crystallization rate of CsPbI2Br films,resulting in small grain size and high defect ***,CsPbI2Br demonstrates poor light absorption due to its wide ***,it is crucial to control the crystallization rate and increase the film thickness to reduce defect density,enhance light absorption,and improve photovoltaic *** this study,we utilized a PbAc2-incorporated twice spincoating（PTS） process to address these ***,PbAc2was added to the CsPbI2Br precursor solution to form a CsPbI2Br film,which was then coated with the CsPbI2Br precursor solution to produce the PTS film,Ac-can delay the perovskite crystallization,leading to the formation of thicker and denser CsPbI2Br ***,lone-pair electrons of the oxygen atom provided by Ac-formed coordination bonds with under-coordinated Pb2+ions to fill halogen ion vacancies,thereby reducing the defect ***,the PTS CsPbI2Br device achieved a peak power conversion efficiency（PCE） of 16.19% and maintained 96.7% of its initial PCE over 1500 h at room temperature under 25% relative humidity without any encapsulation.

关键词： Crystallization management CsPbI2Br PbAc2 Perovskite solar cells Twice spin-coating process

Challenges and perspectives of air pollution control in China

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Frontiers of Environmental Science & Engineering 2024年第6期18卷 9-16页

作者： Bin Zhao Shuxiao Wang Jiming Hao state key Joint laboratory of Environmental Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing 100084China state Environmental Protection key laboratory of Sources and Control of Air Pollution Complex Beijing 100084China

Air pollution is one of the most challenging environmental issues in the *** has achieved remarkable success in improving air quality in last decade as a result of aggressive air pollution control ***,the average fine particulate matter(PM2.5)concentration in China is still about six times of the World Health Organization(WHO)Global Air Quality Guidelines(AQG)and causing significant human health *** emission reductions of multiple air pollutants are required for China to achieve the *** we identify the major challenges in future air quality improvement and propose corresponding control *** main challenges include the persistently high health risk attributed to PM2.5 pollution,the excessively loose air quality standards,and coordinated control of air pollution,greenhouse gases(GHGs)emissions and emerging *** further improve air quality and protect human health,a health-oriented air pollution control strategy shall be implemented by tightening the air quality standards as well as optimizing emission reduction pathways based on the health risks of various *** the meantime,an“oneatmosphere”concept shall be adopted to strengthen the synergistic control of air pollutants and GHGs and the control of non-combustion sources and emerging pollutants shall be enhanced.

关键词： Air pollution China Health impact Air quality standards GHGs Emerging pollutants

Metal–organic framework wafer enabled fast response radiation detection with ultra-low dark current

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Nano Research 2024年第4期17卷 2988-2993页

作者： Meng Xu Jianxi Liu Wei Wu Yang Chen Donghao Ma Sixin Chen Wanqi Jie Menghua Zhu Yadong Xu state key laboratory of Solidification Processing MIIT Key Laboratory of Radiation Detection Materials and Devices&School of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072China

Semiconductive metal–organic frameworks(MOFs)have attracted great interest for the electronic ***,dark currents of present hybrid organic–inorganic materials are 1000–10,000 times higher than those of commercial inorganic detectors,leading to poor charge ***,we demonstrate a ZIF-8(Zn(mim)_(2),mim=2-methylimidazolate)wafer with ultra-low dark current of 1.27 pA·mm^(-2) under high electric fields of 322 V·mm^(-1).The isostatic pressing preparation process provides ZIF-8 wafers with good ***,the presence of redox-active metals and small spatial separation between components promotes the charge *** ZIF-8-based semiconductor detector shows promising X-ray detection sensitivity of 70.82μC·Gy^(-1)·cm^(-2) with low doses exposures,contributing to superior X-ray imaging capability with a relatively high spatial resolution of 1.2 lp·mm^(-1).Simultaneously,good peak discrimination with the energy resolution of~43.78%is disclosed when the detector is illuminated by uncollimated 241Am@5.48 MeVα-*** results provide a broad prospect of MOFs for future radiation detection applications.

关键词： MOFs lead-free α-particles X-ray detection and imaging dark current fast response

Effect of Y,Al Co‑Doping on Hydrogen Storage Properties of La–Mg–Ni‑Based Alloys

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Acta Metallurgica Sinica(English Letters) 2024年第8期37卷 1399-1410页

作者： Guanjiu Wu Yichao Xie Yuan Li Qing Wang Chenfeng Fan Wenfeng Wang Lu Zhang Shumin Han Hebei key laboratory of Applied Chemistry Yanshan UniversityQinhuangdao 066004China state key laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao 066004China

La–Mg–Ni-based hydrogen storage alloys have excellent hydrogen storage *** work reports the hydrogen storage performance of a series of A_(2)B_(7)-type La_(0.96)Mg_(0.04)N_(i3.34)Al_(0.13)alloy and La_(0.96-x)Y_(x)Mg_(0.04)Ni_(3.47–0.6x)Al_(0.6x)(x=0,0.22,0.33,0.44)alloys,and explores the effect of Y and Al element combined substitution on the microstructure and hydrogen storage performance of A_(2)B_(7)-type La–Mg–Ni-based *** alloys are composed of Ce_(2)Ni_(7)phase and LaNi_(5)*** the increase of x,the cell volume of Ce_(2)Ni_(7)phase decreases,while that of LaNi_(5)phase increases,indicating that Y atom mainly enters Ce_(2)Ni_(7)phase and Al atom mainly enters LaNi_(5)*** appropriate amount of co-substitution increases the hydrogen storage capacity and reduces the hydrogen absorption/desorption plateau pressure hysteresis of the *** x=0.44,the hydrogen storage capacity of the alloy is 1.449 wt%,and the hysteresis coefficient is *** cell volume of Ce_(2)Ni_(7)phase and LaNi_(5)phase expands to different degrees after 20 absorption/desorption *** the increase of x,the volume expansion rate decreases,and the cycle capacity retention rate also gradually *** is related to the amorphization of Ce_(2)Ni_(7)*** x=0.22,the capacity retention rate of the alloy is 91.4%.

关键词： La-Mg-Ni-based alloys Gas-phase hydrogen storage performance Ce_(2)Ni_(7)phase LaNi_(5)phase Capacity retention rate