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Crystal Structure of 1,3-Dibenzyl-2-benzylaminothiocarbonyl-1,3,4- diazaphospholidin-5-thione-4-sulfide

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chinese Journal of Structural Chemistry 2002年第1期21卷 31-33页

作者： chi guo-chen② chen ru-yu② (Institute and National Key Laboratory of Elemento-Organic Chemistry, Nankai University, Tianjin 300071, china) 南开大学 National Key Laboratory of Elemento-Organic Chemistry 天津 300071

The title compound, C31H30N3OPS3, crystallizes in monoclinic system, space group P21/n,with a = 11.839(7), b = 8.975(5), c = 29.15(2)? b = 100.07(1), V = 3049(3)?, Z = 4, Dc = 1.280g/cm3, Mr = 587.73, F(000) = 1232, m = 0.324mm-1, the final R = 0.0434 and wR = 0.1140 for 4787 observed reflections with I >2s(I). The title compound is a five-membered heterocycle containing a phosphorus, two nitrogen and two carbon *** analysis result shows that the five-membered ring is nearly coplanar. The P(1)N(1) bond length(1.685? indicates the existence of pd?bond between N(1) and P(1) atoms of the title compound.

关键词： phosphorus heterocycle Lawesson抯 reagent crystal structure

Synthesis and Enhanced Acetone-sensing Properties of Ordered Large-pore Mesoporous Nickel Oxides with Ultrathin Crystalline Frameworks

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Chemical Research in chinese Universities 2024年第3期40卷 521-528页

作者： SHAO chen guo ru LI Hui WANG Xiaozhong YANG Qingfeng LAI Xiaoyong State Key Laboratory of High-efficiency Utilization of Coal and Green Chemical Engineering School of Chemistry and Chemical EngineeringNingxia UniversityYinchuan 750021P.R.China

Acetone is a tracer for monitoring air quality and a potential breath maker for diabetes. It remains a great challenge for current portable sensors to sensitively and selectively detect acetone at low-ppb (part per billion) level. Herein, we present an ordered mesoporous nickel oxide (NiO) with both large mesopores and ultrathin crystalline frameworks for the detection of low-ppb acetone. The ordered mesoporous NiO replicas with predominant large mesopores of 11 nm, high specific surface areas of 121–128 m2/g and ultrathin crystalline frameworks of 5 nm were synthesized by the nanocasting method and the crystalline properties of NiO frameworks were adjusted by changing the annealing temperature from 300℃ to 750℃, which resulted in different contents of oxygen deficient on the surface of ultrathin frameworks. The gas-sensing properties for all the NiO samples were investigated and the ordered large-pore mesoporous NiO (NiO-600) with maximum oxygen deficient obtained at 600℃ exhibited the highest response (R_(gas)/R_(air)−1=2.9) toward acetone (1 ppm, ppm: part per million), which is 3.4 and 30 times larger than those for common mesoporous NiO obtained at 300℃ and bulk NiO. Notably, a low detection limit (2 ppb), good selectivity and cycling stability were also observed in NiO-600.

关键词： Mesoporous semiconductor NiO Gas sensing Acetone

A modern survey method for determining live loads based on multi-source and open-access data on the Internet

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Frontiers of Structural and Civil Engineering 2024年第8期18卷 1135-1147页

作者： chi XU Jun chen Jie LI School of Civil Engineering Tongji UniversityShanghai 200092China The State Key Laboratory on Disaster Reduction in Civil Engineering Tongji UniversityShanghai 200092China

Sufficient survey data are required to describe the stochastic behaviors of live ***,due to manual and on-site operation required by traditional survey methods,traditional surveys face challenges like occupant resistance,high costs,and long implementation *** study proposes a new survey method to access live load data online and *** samples are acquired from multi-source,open-access and dynamically updated data on the *** change intervals,geometrical dimensions and object quantities are obtained from transaction information,building attributes and virtual reality models on real estate websites,*** object weights are collected from commodity information on e-commerce *** integration of the aforementioned data allows for the extraction of necessary statistics to describe a live load *** proposed method is applied to a live load survey in china,covering 20040 m^(2),with around 90000 samples acquired for object weights and load *** survey results reveal that about 70%−80%of the amplitude statistics are attributable to 1/6 of the total object types.

关键词： live load online survey method data acquisition data integration

Analysis of the joint detection capability of the SMILE satellite and EISCAT-3D radar

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Earth and Planetary Physics 2024年第1期8卷 299-306页

作者： JiaoJiao Zhang TianRan Sun XiZheng yu DaLin Li Hang Li JiaQi guo ZongHua Ding Tao chen Jian Wu chi Wang State Key Laboratory of Space Weather National Space Science CenterChinese Academy of SciencesBeijing 100190China Key Laboratory of Solar Activity and Space Weather National Space Science CenterChinese Academy of SciencesBeijing 100190China University of chinese Academy of Sciences Beijing 101408China Key Laboratory of Electronics and Information Technology for Space Systems Chinese Academy of SciencesBeijing 100190China china Research Institute of Radio-wave Propagation Qingdao 266075China

The Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)satellite is a small magnetosphere–ionosphere link explorer developed cooperatively between china and *** pioneers the use of X-ray imaging technology to perform large-scale imaging of the Earth’s magnetosheath and polar cusp *** uses a high-precision ultraviolet imager to image the overall configuration of the aurora and monitor changes in the source of solar wind in real time,using in situ detection instruments to improve human understanding of the relationship between solar activity and changes in the Earth’s magnetic *** SMILE satellite is scheduled to launch in *** European Incoherent Scatter Sciences Association(EISCAT)-3D radar is a new generation of European incoherent scatter radar constructed by EISCAT and is the most advanced ground-based ionospheric experimental device in the high-latitude polar *** has multibeam and multidirectional quasi-real-time three-dimensional(3D)imaging capabilities,continuous monitoring and operation capabilities,and multiple-baseline interferometry *** detection by the SMILE satellite and the EISCAT-3D radar is of great significance for revealing the coupling process of the solar wind–magnetosphere–***,we performed an analysis of the joint detection capability of the SMILE satellite and EISCAT-3D,analyzed the period during which the two can perform joint detection,and defined the key scientific problems that can be solved by joint *** addition,we developed Web-based software to search for and visualize the joint detection period of the SMILE satellite and EISCAT-3D radar,which lays the foundation for subsequent joint detection experiments and scientific research.

关键词： Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)satellite European Incoherent Scatter Sciences Association(EISCAT)-3D radar joint detection

A Systematic Analysis of Early Life Exposure to the chinese Famine(1959-1961)and the Health of Older Adults-china,2008-2023

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china CDC weekly 2024年第11期6卷 203-207,I0001-I0003页

作者： chi Shen Xi chen School of Public Policy and Administration Xi’an Jiaotong UniversityXi’an CityShaanxi ProvinceChina Department of Health Policy and Management Yale School of Public HealthNew HavenCTU.S Department of Economics Yale UniversityNew HavenCTU.S

What is already known about this topic?There is mounting evidence indicating that the aging process initiates during early life stages,with in utero the individual’s environment playing a significant ***,it is crucial to comprehend the enduring effects of early life circumstances on health in old *** is added by this report?In this study,we conducted a meta-analysis to examine the effects of the chinese Famine(1959–1961)on the health of older *** also explored potential mechanisms underlying these *** are the implications for public health practice?The complex interplay between early life circumstances,multiple health-related sectors,and healthy aging necessitates a comprehensive life-course approach and strategic interventions to enhance public health in an aging society.

关键词： life aging mount

Heterogeneous expression of stearoyl-acyl carrier protein desaturase genes SAD1 and SAD2 from Linum usitatissimum enhances seed oleic acid accumulation and seedling cold and drought tolerance in Brassica napus

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Journal of Integrative Agriculture 2024年第6期23卷 1864-1878页

作者： Jianjun Wang Yanan Shao Xin Yang chi Zhang yuan guo Zijin Liu Mingxun chen State Key Laboratory of Crop Stress Biology for Arid Areas/National Yangling Agricultural Biotechnology&Breeding Center/Shaanxi Key Laboratory of Crop Heterosis/College of Agronomy Northwest A&F UniversityYangling 712100China

Flax(Linum usitatissimum L.)is a versatile crop and its seeds are a major source of unsaturated fatty ***-acyl carrier protein desaturase(SAD)is a dehydrogenase enzyme that plays a key role in oleic acid biosynthesis as well as responses to biotic and abiotic ***,the function of SAD orthologs from *** has not been ***,we found that two LuSAD genes,LuSAD1 and LuSAD2,are present in the genome of *** cultivar‘Longya 10’.Heterogeneous expression of either LuSAD1 or LuSAD2 in Arabidopsis thaliana resulted in higher contents of total fatty acids and oleic acid in the ***,ectopic expression of LuSAD2 in *** caused altered plant ***,the overexpression of either LuSAD1 or LuSAD2 in Brassica napus also resulted in increased contents of total fatty acids and oleic acid in the ***,we demonstrated that either LuSAD1 or LuSAD2 enhances seedling resistance to cold and drought stresses by improving antioxidant enzyme activity and nonenzymatic antioxidant levels,as well as reducing membrane *** findings not only broaden our knowledge of the LuSAD functions in plants,but also offer promising targets for improving the quantity and quality of oil,and the abiotic stress tolerance of oil-producing crops,through molecular manipulation.

关键词： LuSAD oleic acid cold tolerance drought tolerance Linum usitatissimum Brassica napus

Atomically Dispersed ruthenium Catalysts with Open Hollow Structure for Lithium-Oxygen Batteries

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Nano-Micro Letters 2024年第2期16卷 154-164页

作者： Xin chen yu Zhang Chang chen Huinan Li yuran Lin Ke yu Caiyun Nan chen chen Beijing Advanced Innovation Center for Materials Genome Engineering Institute of Solid State ChemistryUniversity of Science and Technology BeijingBeijing 100083People’s Republic of China Engineering Research Center of Advanced Rare Earth Materials Department of ChemistryTsinghua UniversityBeijing 100084People’s Republic of China Beijing Key Laboratory of Energy Conversion and Storage Materials Institution College of ChemistryBeijing Normal UniversityBeijing 100875People’s Republic of China

Lithium–oxygen battery with ultrahigh theoretical energy density is considered a highly competitive next-generation energy storage device,but its practical application is severely hindered by issues such as difficult decomposition of discharge products at ***,we have developed N-doped carbon anchored atomically dispersed ru sites cathode catalyst with open hollow structure(h-ruNC)for Lithium–oxygen *** one hand,the abundance of atomically dispersed ru sites can effectively catalyze the formation and decomposition of discharge products,thereby greatly enhancing the redox *** the other hand,the open hollow structure not only enhances the mass activity of atomically dispersed ru sites but also improves the diffusion efficiency of catalytic ***,the excellent activity from atomically dispersed ru sites and the enhanced diffusion from open hollow structure respectively improve the redox kinetics and cycling stability,ultimately achieving a high-performance lithium–oxygen battery.

关键词： Atomically dispersed Open hollow structure Discharge product Lithium Oxygen battery

Di-and tri-methylation of histone H3K36 play distinct roles in DNA double-strand break repair

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Science china(Life Sciences) 2024年第6期67卷 1089-1105页

作者： runfa chen Meng-Jie Zhao yu-Min Li Ao-Hui Liu ru-Xin Wang yu-Chao Mei Xuefeng chen Hai-Ning Du Hubei Key Laboratory of Cell Homeostasis College of Life SciencesTaiKang Center for Life and Medical SciencesFrontier Science Center for Immunology and MetabolismHubei Clinical Research Center of Emergency and ResuscitationEmergency Center of Zhongnan HospitalWuhan UniversityWuhan 430072China Hubei Key Laboratory of Cell Homeostasis College of Life SciencesTaiKang Center for Life and Medical SciencesFrontier Science Center for Immunology and MetabolismWuhan UniversityWuhan 430072China

Histone H3 Lys36(H3K36)methylation and its associated modifiers are crucial for DNA double-strand break(DSB)repair,but the mechanism governing whether and how different H3K36 methylation forms impact repair pathways is ***,we unveil the distinct roles of H3K36 dimethylation(H3K36me2)and H3K36 trimethylation(H3K36me3)in DSB repair via non-homologous end joining(NHEJ)or homologous recombination(HR).Yeast cells lacking H3K36me2 or H3K36me3 exhibit reduced NHEJ or HR efficiency.y Ku70 and Rfa1 bind H3K36me2-or H3K36me3-modified peptides and chromatin,*** these interactions impairs y Ku70 and Rfa1 recruitment to damaged H3K36me2-or H3K36me3-rich loci,increasing DNA damage sensitivity and decreasing repair ***,H3K36me2-enriched intergenic regions and H3K36me3-enriched gene bodies independently recruit y Ku70 or Rfa1 under DSB ***,human KU70 and RPA1,the homologs of y Ku70 and Rfa1,exclusively associate with H3K36me2 and H3K36me3 in a conserved *** findings provide valuable insights into how H3K36me2 and H3K36me3 regulate distinct DSB repair pathways,highlighting H3K36 methylation as a critical element in the choice of DSB repair pathway.

关键词： histone H3K36 methylation Ku70 RPA non-homologous end joining homologous recombination

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Transient long-range distance measurement by a Vernier spectral interferometry

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Photonics Research 2024年第6期12卷 1107-1114页

作者： LIANG XU KUN WANG chen LIU WENYING chen chi ZHANG XINLIANG ZHANG Wuhan National Laboratory for Optoelectronics Huazhong University of Science and TechnologyWuhan 430074China Optics Valley Laboratory Wuhan 430074China

Rapid and long-range distance measurements are essential in various industrial and scientific applications,and among them,the dual-comb ranging system attracts great attention due to its high ***,the tem-poral asynchronous sampling results in the tradeoff between frame rate and ranging precision,and the non-ambiguity range(NAR)is also limited by the comb cycle,which hinders the further advancement of the dual-comb ranging *** this constraint,we introduce a Vernier spectral interferometry to improve the frame rate and NAR of the ranging ***,leveraging the dispersive time-stretch technology,the dual-comb interferometry becomes spectral ***,the asynchronous time step is unlimited,and the frame rate is improved to 100 ***,dual-wavelength bands are introduced to implement a Vernier spectral interferometry,whose NAR is enlarged from 1.5 m to 1.5 ***,this fast and long-range system also demonstrated high precision,with a 22.91-nm Allan deviation over 10-ms averaging *** a result,the proposed Vernier spectral interferometry ranging system is promising for diverse applications that necessitate rapid and extensive distance measurement.

关键词： interferometry spectral system