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Nuclear Science and Techniques 2024年第9期35卷 82-91页

作者： Bing-Bao Mei Liang-Xin Wang song-qi gu Xiao-Zhi Su Shuo Zhang Yao Wei Jing-Yuan Ma Zheng Jiang Fei song Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201800China Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201204China National Synchrotron Radiation Laboratory University of Science and Technology of ChinaHefei 230026China

A Johann-type X-ray spectrometer was successfully developed at the hard X-ray branch(in-vacuum undulator with a 24-mm periodic length)of the energy material beamline(E-line)at the Shanghai Synchrotron Radiation Facility(SSRF).This spectrometer was utilized to implement X-ray emission spectroscopy(XES),high-energy resolution fluorescence-detected X-ray absorption spectroscopy(HERFD-XAS),and resonant inelastic X-ray *** spherically bent crystals were positioned on the respective vertical 500-mm-diameter Rowland circles,adopting an area detector to increase the solid angle to 1.75%of 4πsr,facilitating the study of low-concentrate systems under complex reaction *** under the atmosphere pressure,the spectrometer covers the energy region from 3.5 to 18 keV,with the Bragg angle ranging from 73°to 86°during vertical *** offers a promised energy resolution of sub-eV(XES)and super-eV(HERFD-XAS).Generally,these comprehensive core-level spectroscopy methods based on hard X-rays at the E-line with an extremely high photon flux can meet the crucial requirements of a green energy ***,they provide substantial support for scientific advances in fundamental research.

关键词： X-ray emission spectroscopy High-energy-resolution X-ray spectrometer Johann geometry Energy materials SSRF

Data-collection system for high-throughput X-ray absorption fine structure measurements

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Nuclear Science and Techniques 2016年第4期27卷 38-45页

作者： Rui-You Lu qian Gao song-qi gu Ya-Yun Yang Rui Si Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai 201204 China University of Chinese Academy of Sciences Beijing 100049 China

A new X-ray absorption fine structure(XAFS)data-collection system based on the Experimental Physics and Industrial Control System software environment has been established at the BL14W1 beamline of the Shanghai Synchrotron Radiation Facility. The system provides for automatic sequential analysis of multiple samples for continuous high-throughput(HT) measurements. Specifically, 8 sample pellets are loaded into an alumina holder,and a high-precision two-dimensional translation stage is programmed to switch these samples automatically for collecting the XAFS spectrum of each sample in *** implement HT measurements via a graphical user interface developed with Control System ***, the successful operation of the HT XAFS system is demonstrated by running experiments on two groups of copper–ceria catalysts, each of which contains 8 different powder samples.

关键词： X射线吸收精细结构数据采集系统结构测量高通量上海同步辐射装置 XAFS谱测量与控制系统粉末样品

Soller slits automatic focusing method for multi-element fluorescence detector

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Nuclear Science and Techniques 2016年第5期27卷 179-187页

作者： Ya-Yun Yang qian Gao song-qi gu Hai-Sheng Yu Rui-You Lu Yu-Ying Huang Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai 201204 China University of Chinese Academy of Sciences Beijing 100049 China

In X-ray absorption fine structure(XAFS) experiments,Soller slits are widely used as filter devices in order to improve the signal to noise *** high accuracy manual focusing operations is a time-consuming process;therefore,this work introduces an automatic focusing method for Soller slits in multi-element fluorescence *** method establishes a relation model between the fluorescence intensity distribution and the coordinates of the fluorescence excitation *** to this relation model,the actual coordinates of the fluorescence excitation point can be deduced from the detected fluorescence intensity distribution and used in focusing *** method has proven to be feasible in an XAFS experiment at the BL14W1 beamline of the Shanghai Synchrotron Radiation Facility.

关键词：荧光检测器聚焦方法狭缝 X射线吸收精细结构 XAFS实验关系模型光强度分布高信噪比

Local structural evolutions of CuO/ZnO/Al2O3 catalyst for methanol synthesis under operando conditions studied by in situ quick X-ray absorption spectroscopy

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Nuclear Science and Techniques 2017年第2期28卷 35-43页

作者： Xue-Ping Sun Fan-Fei Sun song-qi gu Jing Chen Xian-Long Du Jian-qiang Wang Yu-Ying Huang Zheng Jiang Shanghai Institute of Applied Physics Chinese Academy of Sciences Zhangjiang Campus Shanghai 201204 China University of Chinese Academy of Sciences Beijing 100049China

In situ quick X-ray absorption spectroscopy(QXAFS) at the Cu and Zn K-edge under operando conditions has been used to unravel the Cu/Zn interaction and identify possible active site of CuO/ZnO/Al_2O_3 catalyst for methanol synthesis. In this work, the catalyst, whose activity increases with the reaction temperature and pressure, was studied at calcined, reduced, and reacted conditions. TEM and EDX images for the calcined and reduced catalysts showed that copper was distributed uniformly at both conditions. TPR profile revealed two reduction peaks at 165 and 195 °C for copper species in the calcined catalyst. QXAFS results demonstrated that the calcined form consisted mainly of a mixed Cu O and Zn O, and it was progressively transformed into Cu metal particles and dispersed Zn O species as the reduction treatment. It was demonstrated that activation of the catalyst precursor occurred via a Cu^+intermediate, and the active catalyst predominantly consisted of metallic Cu and Zn O evenunder higher pressures. Structure of the active catalyst did not change with the temperature or pressure, indicating that the role of the Zn was mainly to improve Cu *** indicates the potential of QXAFS method in studying the structure evolutions of catalysts in methanol synthesis.

关键词： In situ Quick X-ray absorption spectroscopy CuO/ZnO/Al2O3 catalyst Operando condition

Predictors of Adverse Pregnancy Outcomes Following Traumatic Injuries

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Current Medical Science 2024年第3期44卷 642-647页

作者： Wan-rong LU Ping WU Gong song Mei-qi gu Zhe XU Li HE National Clinical Research Center for Gynecology and Obstetrics Cancer Biology Research CenterTongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430030China Department of Traumatic Surgery Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430030China

Objective After traumatic injury in pregnant women,providing timely and appropriate management for high-risk patients is crucial for both pregnant women and *** study aimed to identify risk factors that predict adverse pregnancy outcomes after traumatic *** A retrospective cohort study including 317 pregnant patients who experienced trauma was *** collected data included general demographics,injury mechanisms and adverse pregnancy *** were divided into two subgroups based on the absence or presence of trauma-related adverse pregnancy *** and multivariate logistic regressions were conducted to estimate the associations between clinical variables and adverse pregnancy *** A total of 41(12.93%)patients experienced adverse pregnancy outcomes within the first 24 h *** study revealed that age>35 years(OR=14.995,95%CI:5.024–44.755,P<0.001),third trimester trauma(OR=3.878,95%CI:1.343–11.204,P=0.012),abdominal pain(OR=3.032,95%CI:1.221–7.527,P=0.017),vaginal bleeding(OR=3.226,95%CI:1.093–9.523,P=0.034),positive scan in focused assessment with sonography for trauma(FAST)positive(OR=8.496,95%CI:2.825–25.555,P<0.001),9≤injury severity score(ISS)<16(OR=3.039,95%CI:1.046–8.835,P=0.041)and ISS≥16(OR=5.553,95%CI:1.387–22.225,P=0.015)increased the probability of posttraumatic adverse pregnancy *** age,gestational age at delivery,vaginal bleeding and positive FAST results were risk factors for abnormal *** Advanced maternal age,third trimester,and positive FAST results should alert multidisciplinary trauma teams to closely monitor patients to prevent adverse pregnancy outcomes.

关键词： adverse pregnancy outcomes predictive factors abnormal delivery trauma

Graphene-anchored sodium single atoms:A highly active and stable catalyst for transesterification reaction

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Nano Research 2024年第6期17卷 4979-4985页

作者： song-song Peng Yao Nian Xing-Ru song Xiang-Bin Shao Chen gu Zhi-Wei Xing Shi-Chao qi Peng Tan You Han Xiao-qin Liu Lin-Bing Sun State Key Laboratory of Materials-Oriented Chemical Engineering Jiangsu National Synergetic Innovation Center for Advanced Materials(SICAM)College of Chemical EngineeringNanjing Tech University30 South Puzhu RoadNanjing 211816China School of Chemical Engineering and Technology Tianjin UniversityTianjin 300072China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China

Solid strong base catalysts have received considerable attention in various organic reactions due to their facile separation,neglectable corrosion,and environmental *** great progress has been made in the preparation of solid strong base catalysts,it is still challenging to avoid basic sites aggregation on support and active sites loss in reaction ***,we report a tandem redox strategy to prepare Na single atoms on graphene,producing a new kind of solid strong base catalyst(Na1/G).The base precursor NaNO_(3)was first reduced to Na2O by graphene(400℃)and successively to single atoms Na anchored on the graphene vacancies(800℃).Owing to the atomically dispersed of basicity,the resultant catalyst presents high activity toward the transesterification of methanol and ethylene carbonate to synthesize dimethyl carbonate(turnover frequency(TOF)value:125.7 h^(−1)),which is much better than the conventional counterpart Na2O/G and various reported solid strong bases(TOF:1.0-90.1 h^(−1)).Furthermore,thanks to the basicity anchored on graphene,the Na1/G catalyst shows excellent durability during *** work may provide a new direction for the development of solid strong base catalysts.

关键词： solid strong base catalyst basic sites redox graphene single Na atoms

Explosion damage effects of aviation kerosene storage tank under strong ignition

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Defence Technology（防务技术） 2024年第7期37卷 27-38页

作者： Shixiang song Cheng Wang Boyang qiao Gongtian gu State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China

In order to study the blast damage effects of aviation kerosene storage tanks,the out-field explosion experiments of 8 m3fixed-roof tanks were carried *** fragments,shock wave and fireball thermal radiation of the tank in the presence of bottom oil,half oil and full oil,as well as empty tank,were investigated under internal explosion by various TNT charge contents(1.8 kg,3.5 kg and 6.2 kg).The results showed that the tank roof was the only fragment produced,and the damage forms could be divided into three *** increase of TNT charge content and oil volume enlarged the deformation of the tank,while the hole ratio presented a trend of increase first and then *** H_r,maxand V_(max)values positively increased as increasing the TNT charge content and oil volume(from empty to half oil),but decreased in full *** Pmaxvalues had a progressive increase with the increment of TNT charge content,but not the case with the increase in oil *** development of fireball was divided into three stages:tank roof‘towed'flame,jet flow flame tumbling and rising,and jet flow flame *** Dmaxand Hf,maxvalues both increased as increasing TNT charge content and oil *** oscillation phenomenon of fireball temperature was observed in the cooling *** average temperature of fireball surface was positively correlated with TNT charge content,and negatively correlated with oil volumes.

关键词： Aviation kerosene Storage tank Internal explosion Shock wave Fireball

Flexible polydimethylsiloxane pressure sensor with micro-pyramid structures and embedded silver nanowires:A novel application in urinary flow measurement

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Nanotechnology and Precision Engineering 2024年第3期7卷 1-12页

作者： Ben-song Wang Ang Gao song-Wei Huang qi-Hong Ning Cheng Zhou qi-Xiang song Da-XiangCui School of Electronic Information and Electrical Engineering Shanghai Jiao Tong UniversityShanghai 200240China Department of Urology Renji HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghai 200240China

Flexible pressure sensors are lightweight and highly sensitive,making them suitable for use in small portable devices to achieve precise measurements of tiny *** article introduces a low-cost and easy-fabrication strategy for piezoresistive flexible pressure *** embedding silver nanowires into a polydimethylsiloxane layer with micro-pyramids on its surface,a flexible pressure sensor is created that can detect low pressure (17.3 Pa) with fast response (<20 ms) and high sensitivity (69.6 mA kPa-1).Furthermore,the pressure sensor exhibits a sensitive and stable response to a small amount of water flowing on its *** this basis,the flexible pressure sensor is innovatively combined with a micro-rotor to fabricate a novel urinary flow-rate meter (uroflowmeter),and results from a simulated human urination experiment show that the uroflowmeter accurately captured all the essential shape characteristics that were present in the pump-simulated urination *** ahead,this research provides a new reference for using flexible pressure sensors in urinary flow-rate monitoring.

关键词： Flexible pressure sensor Silver nanowires Portable device Uroﬂowmeter Healthcare

Compressed Data Separation via ℓ_(q)-Split Analysis with ℓ_(∞)-Constraint

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Acta Mathematica Sinica,English Series 2024年第7期40卷 1655-1673页

作者： Ming Yang gu song Li Jun Hong Lin School of Mathematical Science Zhejiang UniversityHangzhou310027P.R.China Center for Data Science Zhejiang UniversityHangzhou310027P.R.China

In this paper,we study compressed data separation(CDS)problem,i.e.,sparse data separation from a few linear random *** propose the nonconvex ℓ_(q)-split analysis with ℓ_(∞)-constraint and 0 详细信息

In this paper,we study compressed data separation(CDS)problem,i.e.,sparse data separation from a few linear random *** propose the nonconvex ℓ_(q)-split analysis with ℓ_(∞)-constraint and 0

关键词： Data separation ℓ_(q)-split analysis Dantzig selector frames restricted isometry property compressed sensing

The essential roles of m^(6)A modification in osteogenesis and common bone diseases

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Genes & Diseases 2024年第1期11卷 335-345页

作者： Yuxi gu Yidan song Yihua Pan Jun Liu State Key Laboratory of Oral Diseases&National Clinical Research Center for Oral Diseases Department of OrthodonticsWest China Hospital of StomatologySichuan UniversityChengduSichuan 610041China

N6-methyladenosine(m^(6)A)is the most prevalent modification in the eukaryotic transcriptome and has a wide range of functions in coding and noncoding *** affects the fate of the modified RNA,including its stability,splicing,and translation,and plays an important role in post-transcriptional *** play a key role in supporting and pro-tecting muscles and other organs,facilitating the movement of the organism,ensuring blood production,*** diseases such as osteoarthritis,osteoporosis,and bone tumors are serious public health *** processes of bone development and osteogenic differen-tiation require the precise regulation of gene expression through epigenetic mechanisms including histone,DNA,and RNA *** a reversible dynamic epigenetic mark,m^(6)A modifications affect nearly every important biological process,cellular component,and molecular function,including skeletal development and *** recent years,studies have shown that m^(6)A modification is involved in osteogenesis and bone-related *** this review,we summarized the proteins involved in RNA m^(6)A modification and the latest progress in elucidating the regulatory role of m^(6)A modification in bone formation and stem cell direc-tional *** also discussed the pathological roles and potential molecular mech-anisms of m^(6)A modification in bone-related diseases like osteoporosis and osteosarcoma and suggested potential areas for new strategies that could be used to prevent or treat bone de-fects and bone diseases.

关键词： Bone diseases m^(6)A modification Osteogenesis Regulatory role Stem cells