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Behaviors analysis of on-coming cluster based on knowledge under cluster security requirements

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Chinese Journal of Aeronautics 2024年第9期37卷 448-462页

作者： Huixia ZHANG Yan LIANG ying shi Yuedong WANG Chaoxiong MA Ran WANG School of Automation Northwestern Polytechnical UniversityXi'an 710129China Key Laboratory of Information Fusion Technology Ministry of EducationXi'an 710129China

Analysis of cluster behaviors of the on-coming cluster is an essential measure for high value locations on the *** target tracking and clustering analysis,cluster behaviors analysis under cluster security requirements remains an open issue,which is a joint analysis of clus-tering,intent reasoning and activity *** address this issue,a framework for cluster behav-iors analysis is proposed by incorporating expert knowledge and domain knowledge,and a knowledge-assisted score function with is designed to improve the accuracy of intent reasoning net-work,overcoming the effects of possible knowledge *** framework consists of three mod-ules for cluster analysis,intent reasoning and activity region analysis for typical tasks,in which an intent reasoning network is constructed to obtain cluster intents by using a hybrid knowledge and data driven ***,considering the complexity of the battlefield environment,dif-ferent tasks and corresponding activity region optimization functions are designed for cluster activ-ity region analysis,which are vital elements of cluster behaviors *** demonstrate the effectiveness of the proposed cluster behaviors analysis framework.

关键词： Cluster analysis Intent reasoning,Activity region analysis Cluster behavior Battlefield environment

Micro-aluminum powder with bi-or tri-component alloy coating as a promising catalyst:Boosting pyrolysis and combustion of ammonium perchlorate

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Defence Technology（防务技术） 2024年第3期33卷 100-113页

作者： Chao Wang ying Liu Mingze Wu Jia Li ying Feng Xianjin Ning Hong Li Ningfei Wang Baolu shi School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China

A novel design of micro-aluminum(μAl)powder coated with bi-/tri-component alloy layer,such as:Ni-P and Ni-P-Cu(namely,Al@Ni-P,Al@Ni-P-Cu,respectively),as combustion catalysts,were introduced to release its huge energy inside Al-core and promote rapid pyrolysis of ammonium perchlorate(AP)at a lower temperature in aluminized *** microstructure of Al@Ni-P-Cu demonstrates that a three-layer Ni-P-Cu shell,with the thickness of~100 nm,is uniformly supported byμAl carrier(fuel unit),which has an amorphous surface with a thickness of~2.3 nm(catalytic unit).The peak temperature of AP with the addition of Al@Ni-P-Cu(3.5%)could significantly drop to 316.2℃ at high-temperature thermal decomposition,reduced by 124.3℃,in comparison to that of pure AP with 440.5℃.It illustrated that the introduction of Al@Ni-P-Cu could weaken or even eliminate the obstacle of AP pyrolysis due to its reduction of activation energy with 118.28 kJ/*** laser ignition results showed that the ignition delay time of Al@Ni-P-Cu/AP mixture with 78 ms in air is shorter than that of Al@Ni-P/AP(118 ms),decreased by 33.90%.Those astonishing breakthroughs were attributed to the synergistic effects of adequate active sites on amorphous surface and oxidation exothermic reactions(7597.7 J/g)of Al@Ni-P-Cu,resulting in accelerated mass and/or heat transfer rate to catalyze AP pyrolysis and ***,it is believed to provide an alternative Al-based combustion catalyst for propellant designer,to promote the development the propellants toward a higher energy.

关键词： Micro-aluminum powder(μAl) Nano-sized alloy coating Combustion catalyst Ammonium perchlorate Pyrolysis behavior Ignition and combustion

Photocatalytic vinyl radical-mediated multicomponent 1,4-/1,8-carboimination across alkynes and olefins/(hetero)arenes

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Science China Chemistry 2024年第2期67卷 558-567页

作者： Shan-Shan Li Yu-shi Jiang xue-Ling Luo Xuming Ran Yuqiang Li Dong Wu Cheng-xue Pan Peng-Ju Xia School of Chemistry and Pharmaceutical Sciences Guangxi Normal UniversityGuilin541004China Shanghai Artificial Intelligence Laboratory Shanghai200433China The Institute for Advanced Studies Wuhan UniversityWuhan430064China

We developed a highly selective and efficient multicomponent transformation by utilizing alkynes and olefins/(hetero)arenes through photoinduced energy-transfer *** reaction involves the formation of three distinct chemical bonds,namely C(sp~3)–C(sp~2),C(sp~2)–C(sp~3),and C(sp~3)–N,in a single coordinated *** strategy used a vinyl radical-mediated radical relay approach under mild conditions,exhibiting a broad substrate scope(>70 examples),excellent functional-group tolerance,and remarkable regio-and *** the utilization of a combination of experimental techniques and density functional theory(DFT),we delved deeper into the mechanistic intricacies of this distinctive *** revealed that the selective radical addition to electron-deficient alkynes,rather than olefins,was governed by the inherent reactivity of alkyl *** discovery presented a highly effective approach for the synthesis of stereodefined multisubstituted alkenes.

关键词： alkyne-olefin coupling DFT studies regio-and anti-stereoselectivity multisubstituted alkenes

Effects of oxygen vacancy on bond ionicity,lattice energy,and microwave dielectric properties of CeO_(2) ceramics with Yb^(3+) substitution

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Journal of Advanced Ceramics 2024年第2期13卷 247-254页

作者： Mingan shi Shuyang Ma Wangsuo Xia ying Wang Jinzi Yu Haitao Wu School of Materials Science and Physics China University of Mining and TechnologyXuzhou 221008China School of Environment and Material Engineering Yantai UniversityYantai 264005China

Novel Yb_(x)Ce_(1-x)O_(2-0.5x)(x=0-0.8)ceramics,designed by replacing Ce^(4+)with Yb^(3+)ions were prepared by conventional oxide reaction,and the structural stability of the cubic fluorite structure was assessed using lattice energy and ionic properties of Ce/Yb-O *** oxygen vacancy caused by unequal substitution,which played a decisive role in bond ionicity and lattice energy,was analyzed experimentally by XPS and also theoretically by first *** Yb_(x)Ce_(1-x)O_(2-0.5x) ceramics maintain a stable cubic fluorite structure when x≤0.47,corresponding to the minimum lattice energy of 4142 kJ/mol with the lowest ionicity as ƒ_(i)=87.57%.For microwave dielectric properties,when the Yb_(x)Ce_(1-x)O_(2-0.5x)(x=0-0.4)ceramics are pure phase,the porosity-corrected permittivity is dependent on the bond *** Q×ƒ values are related to the lattice energy and grain *** temperature coefficient of resonance frequency has been analyzed using bond *** the Yb_(x)Ce_(1-x)O_(2-0.5x)(x=0.5-0.8)ceramics are multiple phases,the microwave dielectric properties are associated with the phase composition and grain growth.

关键词： structure stability bond ionicity oxygen vacancy electronic localization function(ELF)

Electroacupuncture Promotes Angiogenesis in Mice with Cerebral Ischemia by Inhibiting miR-7

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Chinese Journal of Integrative Medicine 2024年第6期30卷 543-550页

作者： YU Qian SHU shi JU Xin-yao PENG Wei REN xue-qi SI Shu-han SONG shi-zhen XIE xue-yun FANG Bang-jiang ZHOU Shuang School of Acupuncture-Moxibustion and Tuina Shanghai University of Traditional Chinese MedicineShanghai201203China College of Basic Medicine Shanghai University of Traditional Chinese MedicineShanghai201203China Department of Emergency Longhua HospitalShanghai University of Traditional Chinese MedicineShanghai200032China

Objective To observe the angiogenesis effect of electroacupuncture(EA)at Shuigou acupoint(GV 26)in the treatment of cerebral ischemia,and explore the value of miRNA-7(miR-7)in *** First,48 mice were randomly divided into sham operation,middle cerebral artery occlusion(MCAO)model,and EA treatment *** 9 mice were divided into carrier control group,miR-7 knockout group and miR-7 overexpression group(n=3 each group).Finally,20 mice were divided into model and carrier control group,model and miR-7 knockout group,EA treatment and carrier control group and EA treatment and miR-7 overexpression group,with 3–6 mice in each *** MCAO model was established in the MCAO and EA *** deficit score and 2,3,5-triphenyltetrazolium chloride(TTC)staining were used to evaluate the severity of cerebral ***-eosin staining was used to describe basic pathological *** was used to quantify cerebral microvessel ***-time PCR and Western blot were used to detect the expression of miR-7 and its downstream target genes Krüppel-like factor 4/vascular endothelial growth factor(KLF4/VEGF)and angiopoietin-2(ANG-2)in the ischemic cerebral *** After EA,neurological deficit scores and infarction volumes decreased,and the density of cerebral microvessels *** the MCAO group,miR-7 expression was higher than that in the sham group(P<0.01).After EA at GV 26,miR-7 expression decreased(P<0.01)and the expression of downstream target genes KLF4/VEGF and ANG-2 increased as compared with the MCAO group(P<0.01).After EA combined with overexpression of miR-7,the expression of downstream target genes KLF4/VEGF and ANG-2 decreased compared to the control EA group(P<0.01).After miR-7 knockdown,the expression of KLF4/VEGF and ANG-2 increased(P<0.05 or P<0.01).Conclusions EA could promote angiogenesis in MCAO mice likely by inhibiting the expression of miR-7 and relieving inhibition of downstream target genes KLF4/VEG

关键词： electroacupuncture cerebral ischemia miRNA-7 angiogenesis Shuigou(GV 26) acupuncture points

Quantifying the agreement and accuracy characteristics of four satellite-based LULC products for cropland classification in China

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Journal of Integrative Agriculture 2024年第1期23卷 283-297页

作者： Jie xue Xianglin Zhang Songchao Chen Bifeng Hu Nan Wang Zhou shi Department of Land Management Zhejiang UniversityHangzhou 310058China Institute of Applied Remote Sensing and Information Technology College of Environmental and Resource SciencesZhejiang UniversityHangzhou 310058China ZJU-Hangzhou Global Scientific and Technological Innovation Center Zhejiang UniversityHangzhou 311215China Department of Land Resource Management School of Public Finance and Public AdministrationJiangxi University of Finance and EconomicsNanchang 330013China Key Laboratory of Data Science in Finance and Economics Jiangxi University of Finance and EconomicsNanchang 330013China Key Laboratory of Spectroscopy Sensing Ministry of Agriculture and Rural AffairsHangzhou 310058China

Various land use and land cover(LULC)products have been produced over the past decade with the development of remote sensing *** the differences in LULC classification schemes,there is a lack of research on assessing the accuracy of their application to croplands in a unified ***,this study evaluated the spatial and area accuracies of cropland classification for four commonly used global LULC products(i.e.,MCD12Q1V6,GlobCover2009,FROM-GLC and GlobeLand30)based on the harmonised FAO criterion,and quantified the relationships between four factors(i.e.,slope,elevation,field size and crop system)and cropland classification *** validation results indicated that MCD12Q1 and GlobeLand30 performed well in cropland classification regarding spatial consistency,with overall accuracies of 94.90 and 93.52%,*** FROMGLC showed the worst performance,with an overall accuracy of 83.17%.Overlaying the cropland generated by the four global LULC products,we found the proportions of complete agreement and disagreement were 15.51 and 44.72% for the cropland classification,*** consistency was mainly observed in the Northeast China Plain,the Huang-Huai-Hai Plain and the northern part of the Middle-lower Yangtze Plain,*** contrast,low consistency was detected primarily on the eastern edge of the northern and semiarid region,the Yunnan-Guizhou Plateau and southern *** size was the most important factor for mapping *** area accuracy,compared with China Statistical Yearbook data at the provincial scale,the accuracies of different products in descending order were:GlobeLand30,FROM-GLC,MCD12Q1,and *** cropland classification schemes mainly caused large area deviations among the four products,and they also resulted in the different ranks of spatial accuracy and area accuracy among the four *** results can provide valuable suggestions for selecting cropland products at the national or provinc

关键词： global LULC products cropland mapping accuracy evaluation food security China

Aboveground biomass stocks of species-rich natural forests in southern China are influenced by stand structural attributes,species richness and precipitation

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Plant Diversity 2024年第4期46卷 530-536页

作者： Wen-Hao Zeng shi-Dan Zhu ying-Hua Luo Wei shi Yong-Qiang Wang Kun-Fang Cao State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources College of ForestryGuangxi UniversityNanning 530004China Guangxi Key Laboratory of Forest Ecology and Conservation College of ForestryGuangxi UniversityNanning 530004China Key Laboratory of National Forestry and Grassland Administration on Biodiversity Conservation in Karst Mountainous Areas of Southwestern China School of Life SciencesGuizhou Normal UniversityHuaxi College TownGui'an DistrictGuiyang 550025China

Forests,the largest terrestrial carbon sinks,play an important role in carbon sequestration and climate change *** forest attributes and environmental factors have been shown to impact aboveground biomass,their influence on biomass stocks in species-rich forests in southern China,a biodiversity hotspot,has rarely been *** this study,we characterized the effects of environmental factors,forest structure,and species diversity on aboveground biomass stocks of 30 plots(1 ha each) in natural forests located within seven nature reserves distributed across subtropical and marginal tropical zones in Guangxi,*** results indicate that forest aboveground biomass stocks in this region are lower than those in mature tropical and subtropical forests in other ***,we found that aboveground biomass was positively correlated with stand age,mean annual precipitation,elevation,structural attributes and species richness,although not with species *** we compared stands with the same basal area,we found that aboveground biomass stock was higher in communities with a higher coefficient of variation of diameter at breast *** findings highlight the importance of maintaining forest structural diversity and species richness to promote aboveground biomass accumulation and reveal the potential impacts of precipitation changes resulting from climate warming on the ecosystem services of subtropical and northern tropical forests in ***,many natural forests in southern China are not fully ***,their continued growth will increase their carbon storage over time.

关键词： Subtropical forest Marginal tropical forest Aboveground biomass Species diversity Forest structural attribute Environment factor

Occurrence and Reduction of Hepatitis B Vaccine Hesitancy Among Medical University Students—Shanxi Province,China,2020

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China CDC weekly 2024年第19期6卷 431-436,I0005-I0007页

作者： Huijuan Kong Xufeng Cui ying Zhang Qiang xue Jing shi Tian Yao Yana Guo Xiuyang Xu Suping Wang Yongliang Feng School of Public Health Shanxi Medical UniversityTaiyuan CityShanxi ProvinceChina Center of Clinical Epidemiology and Evidence Based Medicine Shanxi Medical UniversityTaiyuan CityShanxi ProvinceChina Key Laboratory of Coal Environmental Pathogenicity and Prevention(Shanxi Medical University) Ministry of EducationTaiyuan CityShanxi ProvinceChina First Hospital/First Clinical Medical College of Shanxi Medical University Taiyuan CityShanxi ProvinceChina

Summary What is already known about this topic?Previous research has primarily examined the issue of hepatitis B vaccine hesitancy in migrant workers and other adult ***,there is a lack of studies that have specifical... 详细信息

关键词： Shanxi primarily workers

Catalytic effect in lithium metal batteries: From heterogeneous catalyst to homogenous catalyst

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Journal of Energy Chemistry 2024年第3期90卷 305-326,I0008页

作者： Haining Fan Xuan-Wen Gao Hailong Xu Yichun Ding shi-xue Dou Wen-Bin Luo School of Fashion and Textiles The Hong Kong Polytechnic UniversityHong Kong 100872China Institute for Energy Electrochemistry and Urban Mines Metallurgy School of MetallurgyNortheastern UniversityShenyang 110819LiaoningChina Institute of Energy Materials Science University of Shanghai for Science and TechnologyShanghai 200000China State Key Laboratory of Solidification Processing School of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi'an 710000ShaanxiChina

Lithium metal batteries are regarded as prominent contenders to address the pressing needs owing to the high theoretical *** the broader implementation,the primary obstacle lies in the intricate multi-electron,multi-step redox reaction associated with sluggish conversion kinetics,subsequently giving rise to a cascade of parasitic *** order to smooth reaction kinetics,catalysts are widely introduced to accelerate reaction rate via modulating the energy *** past decades,a large amount of research has been devoted to the catalyst design and catalytic mechanism exploration,and thus the great progress in electrochemical performance has been ***,it is necessary to make a comprehensive review toward key progress in catalyst design and future development *** this review,the basic mechanism of lithium metal batteries is provided along with corresponding advantages and existing challenges detailly *** main catalysts employed to accelerate cathode reaction with emphasis on their catalytic mechanism are summarized as ***,the rational design and innovative direction toward efficient catalysts are suggested for future application in metal-sulfur/gas battery and *** review is expected to drive and benefit future research on rational catalyst design with multi-parameter synergistic impacts on the activity and stability of next-generation metal battery,thus opening new avenue for sustainable solution to climate change,energy and environmental issues,and the potential industrial economy.

关键词： Energy storage and conversion Metal battery Sulfur battery Air battery Catalytic effect Heterogeneous catalyst Homogeneous catalyst