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Mechanical and damping performances of TPMS lattice metamaterials fabricated by laser powder bed fusion

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China Foundry 2024年第4期21卷 327-333页

作者： Yan-peng Wei Huai-qian Li jing-jing Han Ying-chun Ma Hao-ran Zhou jing-chang cheng Jian Shi Zhi-quan miao Bo Yu Feng Lin National Key Laboratory of Advanced Casting Technologies Shenyang Research Institute of Foundry Co.Ltd.CAMShenyang 110022China Department of Mechanical Engineering Tsinghua UniversityBeijing 100084China Key Laboratory of Space Physics Beijing 100076China

Lattice metamaterials based on three-period minimum surface(TPMS)are an effective means to achieve lightweight and high-strength materials which are widely used in various fields such as aerospace and ***,its vibration and noise reduction,and damping properties have not been fully ***,in this study,the TPMS structures with parameterization were designed by the method of surface migration,and the TPMS structures with high forming quality was manufactured by laser powder bed fusion(LPBF).The mechanical properties and energy absorption characteristics of the beam and TPMS structures were studied and compared by quasi-static *** modal shapes of the beam lattice structures and TPMS structures were obtained by the free modal analysis,and the damping properties of two structures were obtained by modal *** the two structures after heat treatment with the same porosity of 70%,the yield strength of the beam lattice structure reaches 40.76 MPa,elastic modulus is 20.38 GPa,the energy absorption value is 32.23 MJ·m^(-3),the damping ratio is 0.52%.The yield strength,elastic modulus,energy absorption value,and damping ratio of the TPMS structure are 50.74 MPa,25.37 GPa,47.34 MJ·m^(-3),and 0.99%,*** results show that TPMS structures exhibit more excellent mechanical properties and energy absorption,better damping performance,and obvious advantages in structural load and vibration and noise reduction compared with the beam lattice structures under the same porosity.

关键词： lattice metamaterials TPMS energy absorption damping laser powder bed fusion

Elevational distribution of forests and its spatiotemporal dynamics in subtropical China from 2000 to 2019

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Science China Earth Sciences 2024年第8期67卷 2563-2582页

作者： Zhencan ZHENG Liuwen ZHUANG Guofang miao Han LIU Zhiqiang cheng Wenyu LI Rong SHANG Peng GONG jing Ming CHEN Institute of Geography Fujian Normal University Key Laboratory of Humid Subtropical Eco-Geographical Process (Ministry of Education) Fujian Normal University School of Geographical Sciences Fujian Normal University National Land Consolidation Center Ministry of Natural Resources Key Laboratory of Land Consolidation and Rehabilitation Ministry of Natural Resources Key Laboratory of Digital Mapping and Land Information Application Ministry of Natural Resources Department of Geography & Planning University of Toronto Department of Geography The University of Hong Kong

The subtropical region of China possesses abundant forest resources and features a mountainous *** the implementation of policies such as natural forest protection,the Grain for Green Project,and other initiatives since the beginning of the 21st century,coupled with climate change,the forest resources in this region have undergone significant changes compared to historical *** addition,forest resources distributing mainly in mountainous areas also implies that these changes may vary significantly with *** explore the spatiotemporal dynamics of forest distribution in subtropical China since 2000,especially the trend of changes with elevation,we analyzed the data from two land cover products focusing on forest cover and forest *** used a hierarchical approach,in which coarse-classification forest cover data with relatively small uncertainties impose constraints on forest type data with larger uncertainties,to achieve a reasonable balance between obtaining more details and reducing data *** first divided the forest cover data into‘unchanged'and‘changed'*** the constraints by the forest cover results,we further analyzed the‘unchanged'and‘changed'forest *** results indicated that,since the implementation of ecological engineering and management policies,54%of the area in the subtropical region had maintained unchanged forest cover attributes over the past 20 years,which implied the good state of ecological *** results also showed that dynamic conversions existed in the long term between forests and lands for essential production needs like *** elevational variations of forest cover suggested that the dominant changes came from the conversion between forests and croplands in low-elevation regions below 700 m,the conversion between forests and shrublands in mid-elevation regions of 700–1500 m,and the conversion between forests and grasslands in high-elevation regions above 2000 *** the regio

关键词： Subtropical China Land cover Forest cover Forest type Elevational distribution

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Polymer-on-HOF:a new strategy for fabricating“armour-plated”HOFs to sequester radioactive anions

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Science China Chemistry 2024年第9期67卷 2958-2967页

作者： Hai-Ruo Li Shitao Wu Xuezhuo jing Zhengyi Di Kun Liu Lu Wang cheng-Peng Li Zhong Liu miao Du College of Chemistry Tianjin Key Laboratory of Structure and Performance for Functional MoleculesTianjin Normal UniversityTianjin 300387China Shanghai Key Laboratory of High-Resolution Electron Microscopy School of Physical Science and TechnologyShanghaiTech UniversityShanghai 201210China Key Laboratory of Comprehensive and Highly Efficient Utilization of Salt Lake Resources Qinghai Provincial Key Laboratory of Resources and Chemistry of Salt LakesQinghai Institute of Salt LakesChinese Academy of SciencesXining 810008China College of Material and Chemical Engineering Institute of New Energy Science and TechnologySchool of Future Hydrogen Energy TechnologyZhengzhou University of Light IndustryZhengzhou 450001China

The development of hydrogen-bonded organic frameworks(HOFs)faces significant constraints,primarily attributed to their fragile architectures and limited functionalization *** overcome these limitations,this work presents a new polymeron-HOF strategy by covalently tethering armor-like polymers onto the surface of *** application of this approach not only bolsters the stability of HOFs,but also facilitates the customization of their functional expansion in radionuclide *** optimized HOF-polymer materials display extraordinary ability in radionuclide sequestration,achieving uptake of I^(-)(0.699 g g^(-1)),IO_(3)^(-)(0.285 g g^(-1))and ReO_(4)^(-)(1.616 g g^(-1),setting a world record),fast adsorption kinetics(~100% removal within 45 s),and exceptional regeneration capability(>30 cycles)under continuous flow *** outstanding performances benefit from the internal porous channels and surface imidazolium polymer coatings of HOFs,as proved by density functional theory calculation and molecular dynamics *** work paves the way for the rational design of HOF-based hybrid materials tailored to versatile applications.

关键词： hydrogen-bonded organic frameworks(HOFs) post-synthetic modification radionuclide sequestration

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Shock Initiation Experiments with Modeling on a DNAN Based MeltCast Insensitive Explosive

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Defence Technology（防务技术） 2024年第2期32卷 655-662页

作者： Feichao miao Dandan Li Yangfan cheng Junjiong Meng Lin Zhou School of Chemical Engineering Anhui University of Science and TechnologyHuainan 232001China Composite Explosive Research Department Xi'an Modern Chemistry Research InstituteXi'an 710065China State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China

2,4-dinitroanisole(DNAN)is a good replacement for 2,4,6-trinitrotoluene(TNT)in melt-cast explosives due to its superior *** the increasing use of DNAN-based melt-cast explosives,the prediction of reaction violence and hazard assessment of the explosives subjected to shock is of great *** study investigated the shock initiation characteristics for a DNAN-based melt-cast explosive,DHFA,using the one-dimensional Lagrangian *** embedded manganin gauges in the apparatus record the pressure histories at four Lagrangian positions and show that shock-todetonation transition in DHFA needs a high input shock *** experimental data are analyzed to calibrate the Ignition and Growth *** calibration is performed using an objective function based on both pressure history and the arrival time of *** agreement between experimental and calculated pressure histories indicates the high accuracy of the calibrated parameters with the optimization method.

关键词： 2,4-Dinitroanisole(DNAN) Shock initiation Insensitive explosives Ignition and growth model Equation of state(EOS)

Editorial Commentary:Top Five Stories of the Cellular Landscape and Therapies of Atherosclerosis:Current Knowledge and Future Perspectives

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Current Medical Science 2024年第1期44卷 241-243页

作者： miao YU Xiang cheng Department of Cardiology Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430022China Hubei Key Laboratory of Biological Targeted Therapy Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430022China Hubei Provincial Engineering Research Center of Immunological Diagnosis and Therapy for Cardiovascular Diseases Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430022China

Atherosclerosis(AS)is the main underlyingpathology of atherosclerotic cardiovascular disease(ASCVD),which is the leading cause of mortality inthe worldwide[1,2].Since the 19th century,Virchowhas already stated that AS is a chronic inflammatorystate induced by *** that,it took at leastthree decades’worth of study to establish the multipleinflammatory pathways related to AS.

关键词： Virchow mortality cardiovascular

Mitigating set-stuck failure in 3D phase change memory: substituting square pulses with surge pulses

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Science China(Information Sciences) 2024年第5期67卷 295-301页

作者： Ninghua LI Wang CAI Jun XIANG Hao TONG Weiming cheng Xiangshui miao School of Integrated Circuits Huazhong University of Science and Technology Hubei Yangtze Memory Laboratories Hubei Institute of Measurement and Testing Technology

In the devices that integrate phase change memory(PCM) and ovonic threshold switching(OTS),the OTS threshold voltage often surpasses the RESET operation voltage of PCM. The conventional application of square pulses hinders the successful completion of the SET operation in these integrated devices. To address this challenge, a novel pulse called the surge pulse is introduced, which comprises a high amplitude pulse for OTS activation and a low amplitude pulse for PCM operation. By employing COMSOL simulation,the operational effectiveness of both square pulses and surge pulses is validated. Test results reveal that using a square pulse to operate the integrated device accelerates the occurrence of SET-stuck failure(SSF).In contrast, the surge pulse enables the integrated device to operate for at least 1000 cycles while preserving the essential cyclic characteristics. Additionally, an investigation into the overshoot component of the surge pulse is conducted, revealing that an increase in overshoot amplitude and pulse width also accelerates the emergence of SSF. By applying the theory of ion migration induced by the electric field, the root cause of SSF in integrated devices is explained, and the accuracy of the theory is validated through the application of a reverse pulse. In summary, this study elucidates the rationality of replacing the square pulse with a surge pulse, presenting a superior approach for operating PCM and OTS integrated devices.

关键词： surge pulse phase change memory (PCM) integration SET-stuck failure (SSF) square pulse

Dual modification of LiNi_(0.83)Co_(0.11)Mn_(0.06)O_(2) cathode materials by K^(+) doping and Li_(3)PO_(4) coating for lithium ions batteries

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Rare Metals 2024年第7期43卷 3007-3018页

作者： Wei Xiao Jia-Le Wang Zhi-cheng Yi cheng-Jin Liu Chang miao Yu Xin Shu-Qing Nie College of Chemistry and Environmental Engineering Yangtze UniversityJingzhou 434023China

Li_(3)PO_(4)@Li_(0.99)K_(0.01)Ni_(0.83)Co_(0.11)Mn_(O.06)O_(2)(NCM-KP) cathode powders are synthesized via K^(+)doping in calcination processes and H_3PO_4 coating in sol-gel processes.K^(+) precisely enters into the lattice to widen the(003) plane to 0.4746 nm with a lower cationic disordered degree of 1.87%.Moreover,the surface residual lithium salts are treated by H_3PO_4 to generate a uniform Li_(3)PO_(4) coating layer of approximately 11.41 nm,which completely covers on the surface of secondary spherical particles to improve the interfacial *** 25℃,the NCM-KP electrode delivers a discharge specific capacity of 148.9 mAh·g^(-1) with a remarkable capacity retention ratio of 84.1% after 200 cycles at 1.0C and retains a high reversible specific capacity of 154.4 mAh·g^(-1) at *** at 1.0C and 60℃,it can maintain a reversible discharge specific capacity of 114.6 mAh·g^(-1) with 0.21% of capacity decay per cycle after 200 cycles,which is significantly lower than 0.40% for the pristine NCM ***,the charge transfer resistance of 238.89 Ω for the NCM-KP electrode is significantly lower than 947.41 Ω for the pristine NCM one by restricting the interfacial side ***,combining K+doping and Li_(3)PO_(4) coating is an effective strategy to enable the significant improvement of the electrochemical property of high-nickel cathode materials,which may be mainly attributed to the widened diffusion pathway and the formed Li_(3)PO_(4) protective layer,thus promoting Li~+diffusion rate and preventing the erosion of HF.

关键词： High-nickel cathode material Residual lithium K^(+)doping Li_(3)PO_(4)coating Lithium ions battery

Health risk assessment of trace metal(loid)s in agricultural soils based on Monte Carlo simulation coupled with positive matrix factorization model in Chongqing, southwest China

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Journal of Mountain Science 2024年第1期21卷 100-112页

作者： MA Jie CHU Lijuan SUN jing WANG Shenglan GE miao DENG Li Chongqing Ecological and Environmental Monitoring Center Chongqing 401147China Key Laboratory of Organic Pollutants in Environmental Chemical Behavior and Ecological Toxicology of Chongqing Chongqing 401147China Department of Pediatrics Chongqing Health Center for Women and ChildrenChongqing 401147China Department of Pediatrics Women and Children’s Hospital of Chongqing Medical UniversityChongqing 401147China

This study aimed to investigate the pollution characteristics, source apportionment, and health risks associated with trace metal(loid)s(TMs) in the major agricultural producing areas in Chongqing, China. We analyzed the source apportionment and assessed the health risk of TMs in agricultural soils by using positive matrix factorization(PMF) model and health risk assessment(HRA) model based on Monte Carlo simulation. Meanwhile, we combined PMF and HRA models to explore the health risks of TMs in agricultural soils by different pollution sources to determine the priority control factors. Results showed that the average contents of cadmium(Cd), arsenic (As), lead(Pb), chromium(Cr), copper(Cu), nickel(Ni), and zinc(Zn) in the soil were found to be 0.26, 5.93, 27.14, 61.32, 23.81, 32.45, and 78.65 mg/kg, respectively. Spatial analysis and source apportionment analysis revealed that urban and industrial sources, agricultural sources, and natural sources accounted for 33.0%, 27.7%, and 39.3% of TM accumulation in the soil, respectively. In the HRA model based on Monte Carlo simulation, noncarcinogenic risks were deemed negligible(hazard index <1), the carcinogenic risks were at acceptable level(10^(-6)

关键词： Monte Carlo simulation Health risk assessment Trace metal(loid)s Positive matrix factorization Agricultural soils

Salivary metabolites are promising noninvasive biomarkers of druginduced liver injury

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World Journal of Gastroenterology 2024年第18期30卷 2454-2466页

作者： Si-miao Yu Hao-cheng Zheng Si-Ci Wang Wen-Ya Rong Ping Li jing jing Ting-Ting He Jia-Hui Li Xia Ding Rui-Lin Wang School of Traditional Chinese Medicine Beijing University of Chinese MedicineBeijing 100029China School of Traditional Chinese Medicine Southern Medical UniversityGuangzhou 510515Guangdong ProvinceChina Department of Hepatology of Traditional Chinese Medicine The Fifth Medical Center of PLA General HospitalBeijing 100039China The First Clinical Medical College Henan University of Traditional Chinese MedicineZhengzhou 450000Henan ProvinceChina

BACKGROUND Drug-induced liver injury(DILI)is one of the most common adverse events of medication use,and its incidence is ***,early detection of DILI is a crucial challenge due to a lack of biomarkers and noninvasive *** To identify salivary metabolic biomarkers of DILI for the future development of noninvasive diagnostic *** Saliva samples from 31 DILI patients and 35 healthy controls(HCs)were subjected to untargeted metabolomics using ultrahigh-pressure liquid chromatography coupled with tandem mass *** analyses,including partial least squares-discriminant analysis modeling,t tests and weighted metabolite coexpression network analysis(WMCNA),were conducted to identify key differentially expressed metabolites(DEMs)and metabolite *** we utilized least absolute shrinkage and selection operato and random fores analyses for biomarker *** use of each metabolite and metabolite set to detect DILI was evaluated with area under the receiver operating characteristic *** We found 247 differentially expressed salivary metabolites between the DILI group and the HC *** WMCNA,we identified a set of 8 DEMs closely related to liver injury for further prediction ***,the distinct separation of DILI patients and HCs was achieved with five metabolites,namely,12-hydroxydodecanoic acid,3-hydroxydecanoic acid,tetradecanedioic acid,hypoxanthine,and inosine(area under the curve:0.733-1).CONCLUSION Salivary metabolomics revealed previously unreported metabolic alterations and diagnostic biomarkers in the saliva of DILI *** study may provide a potentially feasible and noninvasive diagnostic method for DILI,but further validation is needed.

关键词： Drug-Induced liver injury Salivary Metabolomics Biomarker Weighted metabolite Coexpression network analysis Machine learning Noninvasive Diagnostic method Metabolites