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Diversity patterns of cushion plants on the Qinghai-Tibet Plateau:A basic study for future conservation efforts on alpine ecosystems

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Plant Diversity 2022年第3期44卷 231-242页

作者： Ya-Zhou Zhang Li-Shen Qian xu-fang chen Lu Sun Hang Sun Jian-Guo chen Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of BotanyChinese Academy of SciencesKunmingYunnanChina University of Chinese Academy of Sciences BeijingChina School of Life Sciences Yunnan UniversityKunmingYunnanChina

The Qinghai-Tibet Plateau(QTP)is an important cushion plant ***,the distribution of cushion plants on the QTP is unknown,as are the factors that drive cushion plant distribution,limiting our understanding of the evolution of cushion species in the *** this study,we assessed spatial patterns of total cushion plant diversity(including taxonomic and phylogenetic)over the entire QTP and compared patterns of diversity of cushion plants with different typologies(i.e.,compact ***).We also examined how these patterns were related to climatic *** results indicate that the southern QTP hosts the highest total cushion plant richness,especially in the south-central Hengduan Mountains *** total number of cushion species declines from south to north and from southeast to *** cushion plants exhibit similar patterns as the total cushion plant richness,whereas loose cushion plants show random *** plant phylogenetic diversity showed a similar pattern as that of the total cushion plant *** addition,cushion plant phylogenetic community structure was clustered in the eastern and southwestern QTP,whereas random or overdispersed in other *** features represented by annual energy and water trends,seasonality and extreme environmental factors,had significant effects on cushion plant diversity patterns but limited effects on the phylogenetic community structure,suggesting that climatic features indeed promote the formation of cushion *** cushion plants play vital roles in alpine ecosystems,our findings not only promote our understanding of the evolution and formation of alpine cushion plant diversity but also provide an indispensable foundation for future studies on cushion plant functions and thus alpine ecosystem sustainability in the entire QTP region.

关键词： Climatic features Cushion distribution Ecosystem engineer Hengduan mountains Phylogenetic diversity Phylogenetic community structure

Superior compound coatings prepared by low-temperature vanadium-nitrocarburizing duplex treatment

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Rare Metals 2024年第4期43卷 1828-1835页

作者： Gen Jin fang-fang xu xun-xun Hu Yue xu School of Chemistry Beihang UniversityBeijing100191China Guobiao(Beijing)Testing and Certification Co. LtdBeijing100088China School of Materials Science and Engineering Beihang UniversityBeijing100191China

Superior compound coatings were prepared on CK45 steel surface by vanadium-nitrocarburizing duplex treatment in low-temperature salt *** this study,the microhardness,the phase constitution and the compositional distribution in the coatings prepared under different conditions were systematically *** results indicated that the reactions among activated vanadium,carbon and nitrogen atoms occurred on the steel surface,leading to the formation of compound coatings composed of outermost and compound *** mechanism for the formation of compound layer as well as the growth kinetics of the layer was also *** the duplex treatment,the wear and corrosion resistances of steel surface were significantly *** was found that the growth kinetics of compound layer obeyed the parabolic law,with the activation energy of 122.82 kJ·moL^(-1).

关键词： Vanadium-nitrocarburizing duplex treatment Compound coatings Microstructure Formation mechanism Growth kinetics

Survival Analysis of Patients Undergoing Intraoperative Contrast-enhanced Ultrasound in the Surgical Treatment of Malignant Glioma

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Current Medical Science 2024年第2期44卷 399-405页

作者： xu chen Ya-ni PENG fang-ling chenG Dan CAO An-yu TAO Jian chen Department of Neurosurgery Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China Department of Urology Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China Department of Medical Ultrasound Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China

Objective:Complete resection of malignant gliomas is often *** previous study indicated that intraoperative contrast-enhanced ultrasound(ICEUS)could aid in the detection of residual tumor remnants and the total removal of brain *** study aimed to investigate the survival rates of patients undergoing resection with or without the use of ICEUS and to assess the impact of ICEUS on the prognosis of patients with malignant ***:A total of 64 patients diagnosed with malignant glioma(WHO grade HI and IV)who underwent surgery between 2012 and 2018 were *** them,29 patients received *** effects of ICEUS on overall survival(OS)and progression-free survival(PFS)of patients were evaluated.A quantitative analysis was performed to compare ICEUS parameters between gliomas and the surrounding ***:The ICEUS group showed better survival rates both in OS and PFS than the control *** univariate analysis revealed that age,pathology and ICEUS were significant prognostic factors for PFS,with only age being a significant prognostic factor for *** multivariate analysis,age and ICEUS were significant prognostic factors for both OS and *** quantitative analysis showed that the intensity and transit time of microbubbles reaching the tumors were significantly different from those of microbubbles reaching the surrounding ***:ICEUS facilitates the identification of residual *** and ICEUS are prognostic factors for malignant glioma surgery,and use of ICEUS offers a better prognosis for patients with malignant glioma.

关键词： intraoperative contrast-enhanced ultrasound malignant glioma extent of resection survival prognosis

Numerical investigation on thermomechanical behavior of alumina–calcium hexaluminate refractories for purging plug

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Journal of Iron and Steel Research(International) 2024年第2期31卷 389-400页

作者： Li-ping Pan Ya-wei Li fang-guan Tan Yi-chen chen Yang-fan xu Zhu He Bao-kuan Li The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan430081HubeiChina National-Provincial Joint Engineering Research Center of High Temperature Materials and Lining Technology Wuhan University of Science and TechnologyWuhan430081HubeiChina

Alumina–spinel refractories used in slit-type purging plugs are susceptible to cross-sectional damage,resulting in a serious mismatch between their service life and that of ***–calcium hexaluminate refractories have gradually become the new trend in purging plug materials with the development of refining *** thermomechanical damage of slit-type purging plugs with alumina–calcium hexaluminate refractory was investigated by the thermo-solid coupling *** with the polynomial fitting and design of experiments methods,the influence of thermophysical parameters on temperature and thermal stress of alumina–calcium hexaluminate refractories for purging plugs was systematically *** results show that the maximum thermal stress of the purging plugs appears during the stages of steel transporting and stirring,and the vulnerable parts are located above Y=0.323 *** thermal conductivity and the coefficient of thermal expansion of the material are the most sensitive parameters to the temperature and thermal stress inside the structure,*** addition of more calcium hexaluminate can relieve the stress concentration and large deformation around the ***,when the content of calcium hexaluminate is 47 wt.%and in the form of aggregate-binder,the temperature and thermal stress distribution inside the refractory are optimal,which can effectively improve the service life of the slit-type purging plug.

关键词： Purging plug Thermomechanical damage Refractory Design of experiments method Stress

Chronological Study of Coal-seam Water and its Implication on Gas Production in the South Qinshui Basin

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Acta Geologica Sinica(English Edition) 2024年第1期98卷 207-219页

作者： chen Biying fang Lujia LANG Yunchao xu Sheng LIU Congqiang ZHANG Luyuan HOU Xiaolin Institute of Surface-Earth System Science School of Earth System ScienceTianjin UniversityTianjin 300072China Institute of Earth Environments Chinese Academy of SciencesXi’an 710061China

The knowledge of the residence time of formation water is fundamental to understanding the subsurface flow and hydrological *** better identify the origin and evolution of coal seam water and its impact on gas storage and production,this study collected coalbed methane co-produced water in the southeast Qinshui Basin and detected chemical and isotopic compositions,especially 36Cl and 129I *** calculated tracer ages of 129I(5.2–50.6 Ma)and 36Cl(0.13–0.76 Ma)are significantly younger than the age of coal-bearing formation(Pennsylvanian-Cisuralian),indicating freshwater recharge after coal *** model that utilises 129I/I and 36Cl/Cl ratios to constrain the timing of recharge and the proportion of recharge water reveals that over 60%of pre-anthropogenic meteoric water entered coal seams since 10 Ma and mixed with residue initial deposition water,corresponding to the basin inversion in *** spatial distribution of major ion concentrations reveals the primary recharge pathway for meteoric water from coal outcrops at the eastern margin to the basin *** study demonstrates the occurrence of higher gas production rates from wells that accept water recharge in recent times and suggests the possible potential of the non-stagnant zones for high gas production.

关键词： CBM co-produced water iodine-129 chlorine-36 water chemistry Qinshui Basin

Pairs of thiol-substituted 1,2,4-triazole-based isomeric covalent inhibitors with tunable reactivity and selectivity

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Chinese Chemical Letters 2024年第7期35卷 329-335页

作者： Shiqi xu Zi Ye Shuang Shang Fengge Wang Huan Zhang Lianguo chen Hao Lin chen chen fang Hua Chong-Jing Zhang State Key Laboratory of Bioactive Substance and Function of Natural Medicines Beijing Key Laboratory of Active Substance Discovery and Druggability EvaluationInstitute of Materia MedicaChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100050China State Key Laboratory of Bioactive Substance and Function of Natural Medicines Beijing Key Laboratory of New Drug Mechanisms and Pharmacological Evaluation Study(BZ0150)Institute of Materia MedicaPeking Union Medical College and Chinese Academy of Medical SciencesBeijing 100050China The First Affiliated Hospital of Wenzhou Medical University Wenzhou 325000China

Covalent bioactive compounds are successfully used in clinic and attracted intense research efforts in the fundamental study as well as drug *** advantageous effects of covalent compounds compared with non-covalent ones are highly dependent on electrophilic ***,electrophilic warheads with tunable reactivity and selectivity are highly demanded in fields of medicinal chemistry and chemical ***,we report a novel electrophilic warhead,chloromethyl group activated by thiol-substituted 1,2,***,a pair of regioisomers could be simultaneously occurred in the step of alkylation during the synthesis of this unique *** is a rare example that the alkylation could simultaneously generate these two separable regioisomers of 1,2,4-triazole at the nitrogen or sulfur *** covalent-working mechanism of this new warhead is confirmed by various chemoproteomics experiments including target identification and binding site ***,the reactivity and selectivity of this new electrophilic warhead could be efficiently tuned by virtue of stereo ***,one pair of regioisomers(19S and 19X)induced distinct modes of cell *** 19S could induce apoptosis of colon cancer cells while 19X could induce both apoptosis and ***,this study provides pairs of novel electrophilic warheads that could be useful not only in supporting the design of covalent compounds for drug discovery but also in providing chemical probes for the fundamental biological study.

关键词： Electrophilic warhead Covalent inhibitor 1,2,4-Triazole Chemical proteomics GSTO1

Enhanced hydrogen evolution performance by 3D ordered macroporous Ru-CoP@NC electrocatalysts

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Rare Metals 2024年第3期43卷 1095-1107页

作者： chen-chen Zhang Sheng Wei Li-Xian Sun Yi-fang Ouyang Fen xu Hai-Liang Chu Hong-GePan Li-Xin chen xue-Zhang Xiao School of Material Science and Engineering Guilin University of Electronic TechnologyGuilin541004China School of Chemistry and Chemical Engineering Guangxi UniversityNanning530004China Shenzhen Institute of Advanced Technology Chinese Academy of SciencesShenzhen518055GuangdongChina Institute of Science and Technology for New Energy Xi'an Technological UniversityXi'an710021China School of Materials Science and Engineering Zhejiang UniversityHangzhou310058China

Electrocatalytic water splitting coupled with sustainable energies is identified as an environmentally friendly and renewable strategy to generate high-quality hydrogen for the fuel ***,the main challenge is to develop high performance,low cost and chemically stable electrocatalysts to decline the energy barriers and enhance the sluggish kinetics of hydrogen evolution reaction(HER).Herein,a three-dimensional hierarchically ordered macroporous Ru-CoP@NC electrocatalyst(3DOM Ru-CoP@NC)derived from ordered macro-microporous metal-organic frameworks has been prepared using the precursor@template and double-solvent *** prepared 3DOM Ru-CoP@NC catalyst exhibits an overpotential of 15 mV(j=10 mA·cm^(-2))and a reaction Tafel slope of 38 mV·dec^(-1)in alkaline electrolyte,which are superior to commercial Pt@C ***,the overpotential and reaction Tafel slope of this catalyst in acidic media are 45 mV and 50 mV·dec^(-1),*** outstanding HER activities of 3DOM Ru-CoP@NC catalysts are ascribed to the 3D highly interconnectedreticular nanospaces that can increase effective reaction active *** N dope d carbon framework improves the electronic properties and ***,the strong interaction of Ru and CoP nanoparticles also boosts the HER *** results indicate that 3DOM Ru-CoP@NC catalysts with high catalytic activities have a broad application prospect in the future.

关键词： Hydrogen evolution reaction Template method 3D ordered macroporous Ru-CoP@NC

Multifunctional Integrated Organic-Inorganic-Metal Hybrid Aerogel for Excellent Thermal Insulation and Electromagnetic Shielding Performance

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Nano-Micro Letters 2024年第10期16卷 163-175页

作者： Zhaoqi Niu Fengjin Qu fang chen Xiaoyan Ma Beixi chen Luyao Wang Miao xu Shumeng Wang Liang Jin chengshuang Zhang Xiao Hou Ministry of Industry and Information Technology Key Laboratory of Special Function and Smart Polymer Materials Key Laboratory of Materials Physics and Chemistry of Ministry of Education for Extraordinary ConditionsNorthwestern Polytechnical UniversityXi'an 710072People's Republic of China Spallation Neutron Source Science Center Institution Dongguan 523803People's Republic of China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049People's Republic of China China Aerospace Science and Industry Corporation Sixth Academy Hohhot 022185People's Republic of China Xi'an Aerospace Composites Research Institute Xi'an 710025People's Republic of China China Aerospace Science and Technology Corporation Beijing 100037People's Republic of China

Vehicles operating in space need to withstand extreme thermal and electromagnetic environments in light of the burgeoning of space science and *** is imperatively desired to high insulation materials with lightweight and extensive mechanical ***,a boron-silica-tantalum ternary hybrid phenolic aerogel(BSiTa-PA)with exceptional thermal stability,extensive mechanical strength,low thermal conductivity(49.6 mW m^(-1)K^(-1)),and heightened ablative resistance is prepared by an expeditious *** extremely thermal erosion,the obtained carbon aerogel demonstrates noteworthy electromagnetic interference(EMI)shielding performance with an efficiency of 31.6 dB,accompanied by notable loading property with specific modulus of 272.8 kN·m kg^(-1).This novel design concept has laid the foundation for the development of insulation materials in more complex extreme environments.

关键词： Multi-hybrid aerogel Metal-phenolic coordination Thermal insulation EMI shielding Convertibility and multifunctionality

A methodology for laser tool setters calibration and its precise mathematical model

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Chinese Journal of Aeronautics 2024年第7期37卷 564-581页

作者： Tao fang Zixi fang Ze Zhong chen Zhiyong CHANG School of Mechanical Engineering Northwestern Polytechnical UniversityXi’an 710072China Gina Cody School of Engineering and Computer Science Concordia UniversityMontrealQuebec H3G 1M8Canada Changsha Optimum CNC Corporation Changsha 410221China Institute for Aero-engine Smart Assembly of Shaanxi Province Xi’an 710072China

On-machine tool setting is a pivotal approach in achieving intelligent manufacturing,and laser tool setters have become a crucial component of smart machine *** tool setters play a crucial role in precisely measuring the dimensions of cutting tools during the part machining process,focusing on tool length and *** a measuring instrument,the positions of the laser axis of the laser tool setter need to be accurately calibrated before ***,in actual calibration scenarios,traditional calibration methods face challenges due to installation errors in the tool setter and geometric errors in the measuring *** address this issue,this study proposes a novel calibration ***,the calibration mechanism of the laser beam axis is *** on the accurate mathematical model of the laser beam and the measuring rod,and using the polygon clipping algorithm,the mathematical mechanism of the laser tool setter’s work is ***,a novel method is introduced to calculate the compensation distance between the laser beam reference point and the rod bottom center point at each moment during ***,by utilizing the kinematic chain of the tool setter calibration system,a new calibration method is developed to accurately calibrate the position of the laser beam axis in the machine tool coordinate ***,the accuracy of the calibration method is verified through simulation experiments and calibration *** method improves the calibration accuracy of the tool setter,and the mathematical model of the laser tool setter can be extended to the measurement of tools,thereby improving the precision of tool *** research significantly improves the efficient production performance of smart machine tools.

关键词： On-machine tool setting Smart machine tools Mathematical model Calibration method Laser tool sette