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Dative B–N bonds weaven toward two-dimensional purely organic materials for single crystals

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Science China Chemistry 2025年第1期68卷 12-14页

作者： Wei-lei zhou Siwei Wang Yong Chen College of Chemistry and Materials Science Inner Mongolia Key Laboratory of Chemistry for Nature Products and Synthesis for Functional MoleculesInnovation Team of Optical Functional Molecular DevicesInner Mongolia Minzu UniversityTongliao 028000China College of Chemistry Nankai UniversityTianjin 300071China

Molecular topology is one of the important topics to study and understand the relationship between molecular structure and properties^([1]).Particularly,two-dimensional(2D)materials with extremely high surface area and ultra-thin morphology have attracted considerable attention due to their unexpected properties in materials and chemistry^([2,3]).

关键词： bonds purely dimensional

Statistical characteristics and classification of ionospheric mid-latitude trough as revealed by the observations of DMSP-F18

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Earth and Planetary Physics 2025年第1期9卷 137-147页

作者： Yi Liu JiuHou lei FuQing Huang Su zhou School of Earth and Space Sciences University of Science and Technology of ChinaHefei 230026China School of Science Guiyang UniversityGuiyang 550005China

Statistical characteristics and the classification of the topside ionospheric mid-latitude trough are systemically analyzed,using observations from the Defense Meteorological Satellite Program F18(DMSP-F18)*** data was obtained at an altitude of around 860 km in near polar orbit,throughout *** study identified the auroral boundary based on the in-situ electron density and electron spectrum,allowing us to precisely determine the location of the mid-latitude *** differs from most previous works,which only use Total Electron Content(TEC)or in-situ electron *** our study,the troughs exhibited a higher occurrence rate in local winter than in summer,and extended to lower latitudes with increasing geomagnetic *** was found that the ionospheric mid-latitude trough,which is associated with temperature changes or enhanced ion drift,exhibited distinct ***,the ionospheric mid-latitude troughs related to electron temperature(Te)peak were located more equatorward of auroral oval boundary in winter than in *** ionospheric mid-latitude troughs related to Te-maximum were less frequently observed at 60−70°S magnetic latitude and 90−240°E ***,the troughs related to ion temperature(Ti)maximums were observed at relatively higher latitudes,occurring more frequently in *** addition,the troughs related to ion velocity(Vi)maximums could be observed in all *** troughs with the maximum-Ti and maximum-Vi were located closer to the equatorward boundary of the auroral oval at the nightside,and in both *** implies that enhanced ion drift velocity contributes to increased collisional frictional heating and enhanced ion temperatures,resulting in a density depletion within the trough region.

关键词： topside ionosphere mid-latitude trough ionospheric main trough auroral oval boundary temperature maximum

Perspectives on additive manufacturing for warhead applications

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Defence Technology(防务技术) 2025年第1期43卷 225-251页

作者： Hao Xue Qiang zhou Chuan xiao Guangyan Huang State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China Ordnance Science and Research Academy of China Beijing 100089China Beijing Institute of Technology Chongqing Innovation Center Chongqing 401120China

According to different damage modes,warheads are roughly divided into three types:fragmentation warheads,shaped charge warheads,and penetrating *** to limitations in material and structural manufacturing,traditional manufacturing methods make it difficult to fully utilize the damage ability of the *** manufacturing(AM)technology can fabricate complex structures,with classified materials composition and customized components,while achieving low cost,high accuracy,and rapid production of the *** maturity of AM technology has brought about a new round of revolution in the field of *** this paper,we first review the principles,classifications,and characteristics of different AM *** development trends of AM technologies are pointed out,including multi-material AM technology,hybrid AM technology,and smart AM *** our survey,PBF,DED,and EBM technologies are mainly used to manufacture warhead damage *** and DIW technologies are mainly used to manufacture warhead ***,the research on the application of AM technology in three types of warhead and warhead charges was reviewed and the existing problems and progress of AM technologies in each warhead were ***,we summarized the typical applications and look forward to the application prospects of AM technology in the field of warheads.

关键词： Additive manufacturing Fragmentation warhead Shaped charge warhead Penetrating warhead Warhead charge

Nanoplastics and nano-ZnO facilitate Cd accumulation in zebrafish larvae via a distinct pathway: Revelation by LA-ICP-MS imaging

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Chinese Chemical Letters 2025年第2期36卷 436-440页

作者： Pengyu Chen Beibei Chen Man He Yuxi zhou lei lei Jian Han Bingsheng zhou Ligang Hu Bin Hu Department of Chemistry Wuhan University State Key Laboratory of Freshwater Ecology and Biotechnology Institute of Hydrobiology Chinese Academy of Sciences State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences

The interaction between nanoparticles （NPs） and pollutants affects their bioavailability and ***,the processes by which NPs and pollutants change in vivo have rarely been ***,using laser ablation-inductively coupled plasma-mass spectrometry （LA-ICP–MS）,we found that both nanoplastics and ZnO NPs caused more Cd to accumulate in zebrafish larvae,but with distinct *** could adsorb Cd2+and transfer it into the larvae through the“Trojan horse”*** coexposure of nanoplastics and Cd2+caused Cd to accumulate in the abdomen where the nanoplastics were located without dissociation,showing a lower toxic effect than Cd2+exposure *** NPs weakly adsorbed Cd2+,but they increased the Zn and Cd contents in larvae by enhancing the expression of metal *** coexposure of ZnO and Cd2+evenly distributed Cd in the larvae,revealing a more severe toxic effect than Cd2+exposure *** results demonstrated the changing bioavailability and toxicity of Cd induced by different *** also shows the vital role LA-ICP-MS plays in revealing the relationship between toxicity and *** addition,the long-term effect of bioavailability on heavy metal toxicity and nanosafety deserves further investigation.

关键词： Cadmium Combined effect LA-ICP-MS Nanoplastics Zebrafish larvae ZnO nanoparticles

Design and Application of Turbine Cascade Partitioned Endwall Profiling

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Journal of Thermal Science 2025年第1期34卷 110-128页

作者： ZENG Fei JIANG Ruiqi XUE Xingxu DU Wei LUO lei zhou Xun AECC Hunan Aviation Powerplant Research Institute Zhuzhou 412002China School of Energy Science and Technology Harbin Institute of TechnologyHarbin 150001China Science and Technology on Diesel Engine Turbocharging Laboratory China North Engine Research InstituteTianjin 300270China

The influence of partitioned profiling design based on a large-pitch highly loaded cascade is studied by numerical *** partitioned profile is mainly composed of a pressure-side convex structure near the leading edge and a suction-side convex structure at the midstream and downstream sides of the *** influence of the change in the vertex axial position and peak value of the B-line on the secondary flow control is *** this paper,air(ideal gas)is selected as the flow *** average static pressure at the outlet and the average total temperature at the inlet are kept *** γ-θ is used as the turbulence *** results show that the pressure-side convex structure suppresses the spanwise and pitchwise migration of the inlet flow by adjusting the static pressure distribution of the flow field,so the development of the pressure-side leg of the horseshoe vortex is effectively *** suction-side convex structure adjusts the static pressure distribution of the flow field and increases the included angle between the cross-flow and suction surface,so the accumulation of low-momentum fluid,the development of a corner vortex and the flow separation at the trailing edge of the suction-side surface are all suppressed near the endwall-suction ***,the energy loss coefficient of the large-pitch highly loaded cascade is decreased from 0.0564 to 0.0485,representing a 25% reduction in secondary flow losses.

关键词： large-pitch highly loaded cascade highly loaded design non-axisymmetrical endwall design secondary flow control partitioned endwall profiling

Significant improvement of machinability of C_(f)/SiC composites through matching laser scanning spacing and abrasive belt grain size

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Chinese Journal of Aeronautics 2025年第1期38卷 185-201页

作者： Guijian xiao Zhengyu YANG Kun zhou Yi HE Xin LI College of Mechanical and Vehicle Engineering Chongqing UniversityChongqing 400044China State Key Laboratory of Mechanical Transmissions for Advanced Equipment Chongqing UniversityChongqing 400044China

To improve the application and service of C_(f)/SiC composites as advanced hightemperature structural materials,it is critical to achieve their high-efficiency and low-damage *** this study,the laser-ablating assisted grinding(LAAG)method was presented,and the connection of damage behavior and removal mechanism with laser and grinding processes was *** results demonstrated that the surface of C_(f)/SiC composites after laser ablation was covered with a substantial number of loose oxides primarily composed of *** ablating process,grinding parameter and abrasive belt selection have a significant impact on the machining *** fabricating an ablative layer with small laser scanning spacing,and selecting small abrasive grains and feed rate during grinding,the machinability was improved and a relatively lowerdamage grinding surface could be *** the optimal combination of process parameters,the grinding force and temperature of LAAG could be reduced by up to 85%and 35%,*** this case,the subsurface damage of C_(f)/SiC composites occurred only in the form of microcracks rather large-scale fracture,and the formation of interface debonding and matrix cracking was significantly ***,the grinding chips were mostly shown as micron-sized powders,indicating that the removal mechanism of C_(f)/SiC composites was primarily the microfractured and attrition wear of laser-ablated layer.

关键词： Ceramic matrix composites Laser ablating Grinding Material removal Fracture damage

A new aristolactam alkaloid from the stems of Dasymaschalon trichophorum

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中国天然药物 2013年第1期11卷 81-83页

作者： zhou xiao-lei WU Jiu-Hong BAI Jiao HU xiao-Lan LI En-Zhen SHINing PEI Yue-Hu Department of Pharmacy The 306th hospital of PLA Beijing 100101 China School of rra-ditional Chinese Materia Medica Shenyang P-harmaceutical University Shenyang 110016 China Institute of Pharmacology and Toxicology Academy of Military Medical Sciences Be(jing 100850 China

试图学习混合物被各种各样的层析的方法孤立并且净化的 Dasymaschaon trichophorum Merr 方法的茎的化学成分。他们的结构根据分光镜的方法被阐明。结果五 aristolactam 碱被获得，他们的结构作为 10-amino-3,6-dihydroxy-2,4-dimethoxy... 详细信息

试图学习混合物被各种各样的层析的方法孤立并且净化的 Dasymaschaon trichophorum Merr 方法的茎的化学成分。他们的结构根据分光镜的方法被阐明。结果五 aristolactam 碱被获得，他们的结构作为 10-amino-3,6-dihydroxy-2,4-dimethoxyphenanthrene-1-carboxylic 酸被识别酮(1 ) ， enterocarpam-II (2 ) ， oldhamactam (3 ) ， goniopedaline (4 ) ，和 stigmalactam (5 ) 分别地。结论化合物 1 是新 aristolactam 碱，当时混合物 25 第一次从这个类被报导。

关键词：番荔枝科皂帽花生物碱

Distribution and Hydrogeochemical Characteristic of High Iodine Groundwater in Oasis Zone in the Tarim Basin in Xinjiang,China

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Journal of Earth Science 2025年第1期36卷 173-183页

作者： Ying Sun Yinzhu zhou Jinlong zhou Yanyan Zeng Yuanyuan Ji Mi lei College of Hydraulic and Civil Engineering Xinjiang Agricultural UniversityUrumqi 830052China Xinjiang Hydrology and Water Resources Engineering Research Center Urumqi 830052China Xinjiang Key Laboratory of Hydraulic Engineering Security and Water Disasters Prevention Urumqi 830052China Center for Hydrogeology and Environmental Geology China Geological SurveyTianjin 300304China Xinjiang Agricultural Professional Technological College Changji 831100China

Groundwater is the main water supply source in the Tarim Basin in *** disease caused by high iodine(I)groundwater in the Tarim Basin was reported ***,it is crucial to systematically identify the distribution and genesis of groundwater *** on hydrochemical analysis of 717 groundwater samples collected in 2015–2018,spatial distribution and hydrogeochemistry characteristic of high I groundwater in different aquifers were *** showed that groundwater I ranged between100.00μg/L)accounted for 7.25%of the total ***,groundwater I significantly increased from recharge zone(RZ)to transition zone(TZ)and to evaporation zone(EZ).Vertically,groundwater in shallow confined aquifer(SCA)had the greatest I concentration,followed by single-structure phreatic aquifer(SSPA),phreatic aquifer in confined groundwater area(PACGA),while groundwater in deep confined aquifer(DCA)generally had low I *** I enrichment in SSPA was mainly affected by organic matter(OM)decomposition and that in SCA was mainly affected by evaporite mineral dissolution,OM decomposition under alkaline *** I enrichment in groundwater of PACGA was restrained under neutral *** sedimentary environment was crucial for I enrichment in ***,fine-grained lithology of aquifer,smooth topographic slope,shallow buried depth of groundwater,weak alkaline and reducing environment,reductive dissolution of iron oxide/hydroxide minerals and OM decomposition were advantageous to I enrichment in groundwater.

关键词： high iodine groundwater hydrogeochemical processes depositional environment hydrogeological condition Tarim Basin

A FUNCTIONAL ORLICZ BUSEMANN-PETTY CENTROID INEQUALITY FOR LOG-CONCAVE FUNCTIONS

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Acta Mathematica Scientia 2025年第1期45卷 52-71页

作者： xiao LI Jiazu zhou School of Mathematical Sciences Chongqing Normal UniversityChongqing401331China School of Mathematics and Big Data Guizhou Education UniversityGuiyang550018China

In this paper,the Orlicz centroid function for log-concave functions is introduced.A rearrangement inequality of the Orlicz centroid function for log-concave functions is *** rearrangement inequality implies the Orlic... 详细信息

关键词： centroid bodies Busemann-Petty centroid inequality log-concave functions Steiner symmetrization