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Research on the navigation method of large-scale differential tail-control improvised guided munitions based on rotational speed constraints

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Defence Technology（防务技术） 2024年第8期38卷 155-170页

作者： ning Liu Wenjiang Zhao Yao Wang kai shen Zhong su Wenhao Qi Yuedong Xie Beijing Key Laboratory of High Dynamic Navigation Technology Beijing Information Science and Technology UniversityBeijing100192China Hua an industry Group Co. Ltd.Qiqihar161006China integrated Navigation and intelligent Navigation Laboratory Beijing Institute of TechnologyBeijing100081China Beijing ins.itute of Technology Beijing100081China

in the process of launching guided projectile under the conventional system, it is difficult to effectively obtain the precise navigation parameters of the projectile in the high dynamic environment. Aiming at this problem, this paper describes a new system of guided ammunition based on tail s.in reduction. After analyzing the mechanism of the ammunition's tail s.in reduction, a navigation method of large scale difference tail control simple guided ammunition based on speed constraint is proposed. in this method,the corresponding navigation constraints can be carried out by combining the rotation speed state of the ammunition itself, and the optimal solution of navigation parameters during the flight of the mis.ile can be obtained by Extended Kalman Filter(EKF). Finally, the performance of the proposed method was verified by the simulation environment, and the hardware-in-the-loop simulation test and flight test were carried out to verify the performance of the method in the real environment. The experimental results show that the proposed method can achieve the optimal es.imation of navigation parameters for simple guided ammunition with large-scale difference tail control. Under the conditions of simulation test and hardware-in-loop simulation test, the position and velocity errors calculated by the method in this paper converged. Under the condition of flight test, the spatial average error calculated by the method described in this paper is 6.17 m, and the spatial error of the final landing point is 3.50 *** this method, the accurate acquisition of navigation parameters.in the process of projectile launching is effectively realized.

关键词： Guided projectiles Tail s.in reduction RPM constraints Combined navigation Extended Kalman filter(EKF)

A Comprehensive Approach to improving Children’s and Adolescents’Mental Health

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China CDC weekly 2024年第40期6卷 1017-1021页

作者： ning Zhang school of Public Health and the second Affiliated Hos.ital of Zhejiang University school of Medicine Hangzhou CityZhejiang ProvinceChina

The increasing Prevalence of Mental Health Problems Among Children and Adolescents.in China The prevalence of mental health issues among children and adolescents.in China has continuously increased over the past few *** to a recent national psychiatric epidemiological survey of 17,524 school-aged children and adolescents,the prevalence of mental health disorders was 17.5%[95%confidence interval(Ci):17.2%,18.0%].

关键词： prevalence Children Health

study on a probabilis.ic algorithm for the forming and 3D characterization of special-shaped surfaces under profile grinding

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Advances.in Manufacturing 2024年第2期12卷 288-299页

作者： Zhao-Qing Zhang kai-ning s.i Yao-Yao s.i Yi-Hui song Zhe He Ya-song Pu school of Mechanical Engineering Northwestern Polytechnical UniversityXi’an710072People’s Republic of China Key Laboratory of High Performance Manufacturing for Aero Engine(Northwestern Polytechnical University) Ministry of Industry and Information TechnologyXi’an710072People’s Republic of China Engineering Research Center of Advanced Manufacturing Technology for Aero Engine(Northwestern Polytechnical University) Ministry of EducationXi’an710072People’s Republic of China

Profile grinding is the most crucial method for the ultra-precision machining of special-shaped ***,profile grinding produces a unique machining profile,and many random factors.in the machining process lead to complex surface *** this study,the structural and probabilis.ic characteris.ics of the profile grinding of a special-shaped surface were analyzed,and a probabilis.ic algorithm for the forming and 3D characterization of special-shaped surfaces under profile grinding was *** forming process of a GH738 blade tenon tooth surface was considered as an example to demonstrate the *** comparison results showed that the simulation results had similar surface characteris.ics to the measurement results,and the relative error range of the 3D roughness parameter was 0.21%–19.76%,indicating an accurate prediction and characterization of the complex special-shaped surface under the action of multiple factors.

关键词： special-shaped surface Profile grinding surface morphology 3D characterization

Health-oriented strategies are needed to optimize China’s 2025 clean air action plan

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s.ience Bulletin 2024年第13期69卷 2007-2008页

作者： Tao Xue ning Kang Wei Wan Tong Zhu ins.itute of Reproductive and Child Health/National Health Commis.ion Key Laboratory of Reproductive Health and Department of Epidemiology and Biostatis.ics/Ministry of Education Key Laboratory of Epidemiology of Major Diseases(PKU) School of Public HealthPeking University Health Science CentreBeijing 100191China state Environmental Protection Key Laboratory of Atmospheric Exposure and Health Risk Management Center for Environment and HealthPeking UniversityBeijing 100871China Advanced ins.itute of information Technology Peking UniversityHangzhou 311215China Clean Air Asia Beijing 100600China College of Environmental s.iences and Engineering Peking UniversityBeijing 100871China

Recently,China’s state Council issued the Continuous.improvement of Air Quality Action Plan(hereafter,the third action plan),which follows the Air Pollution Prevention and Control Action Plan(2013–2017)(hereafter,the first action plan)and the Three-Year Action Plan for Winning the Blue sky Defense Battle(2018–2020)(hereafter the second action plan).The first two action plans yielded nationwide health benefits[1–3],from improving lung function[4]to saving medical expenditures[5].Based on our previous es.imates[6],due to reductions.in the fine particulate matter(PM2.5)level,implementation of the first and second action plans was expected to increase life expectancy by 2.11 and 3.68 months.

关键词： action hereafter nationwide

Recent progress.in Cds-based s-scheme photocatalysts

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Journal of Materials s.ience & Technology 2024年第4期171卷 162-184页

作者： Yajing Ren Yunfeng Li Guixu Pan ning Wang Yan Xing Zhenyi Zhang College of Environmental and Chemical Engineering Xi’an Polytechnic UniversityXi’an 710048China Jilin Provincial Key Laboratory of Advanced Energy Materials Department of ChemistryNortheast Normal UniversityChangchun 130024China Key Laboratory of New Energy and Rare Earth Resource Utilization of state Ethnic Affairs Commis.ion Key Laboratory of Photosensitive Materials and Devices of Liaoning ProvinceSchool of Physics and Materials EngineeringDalian Minzu UniversityDalian 116600China

Photocatalytic technology with sunlight as driving force can convert solar energy into other energy sources for storage and further *** sulfide(Cds),as a typical reducing semiconductor of metal sulfides,represents an interes.ing research hotspot in photocatalysis due to its s.itable bandgap(2.4 eV)for utilizing visible light and strong reducing ability for inducing surface catalytic ***,the photocatalytic performance of Cds.is s.ill limited by its fast carrier recombination and serious *** far,Cds semiconductor has been widely developed as a typical reducing photocatalyst in constructing novel s-scheme heterojunction to overcome the above *** this review,the de-sign concepts,basic principles,and charge transfer characteris.ics of Cds-based s-scheme heterojunction photocatalysts have been comprehensively *** advanced and effective characterization methods for studying the mechanism of Cds-based s-scheme heterojunction are analyzed in ***-thermore,we also summarize the typical applications of Cds-based s-scheme heterojunctions for water splitting,CO_(2) reduction,pollutant degradation,***,according to the current inves.igation sta-tus,some drawbacks.in the current synthetic strategy,mechanism exploration,and application prospect of Cds-based s-scheme heterojunction are proposed,which need to be addressed by further expansion and innovative research.

关键词： Photocatalysis Cds semiconductor Heterojunction s-scheme Metal sulfide

Highly stretchable kirigami-patterned nanofiber-based nanogenerators for harves.ing human motion energy to power wearable electronics

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Materials Futures 2024年第2期3卷 131-140页

作者： Chuan ning shengxin Xiang Xiupeng sun Xinya Zhao Chuanhui Wei Lele Li Guoqiang Zheng kai Dong College of Materials s.ience and Engineering Key Laboratory of Material Processing and Mold(Ministry of Education)Zhengzhou UniversityZhengzhou 450001People’s Republic of China Key Laboratory of Materials Physics Ministry of EducationSchool of Physics and MicroelectronicsZhengzhou UniversityZhengzhou 450001People’s Republic of China CAs Center for Excellence in Nanos.ience Beijing Key Laboratory of Micro-Nano Energy and SensorBeijing Institute of Nanoenergy and NanosystemsChinese Academy of SciencesBeijing 101400People’s Republic of China school of Nanos.ience and Technology University of Chinese Academy of SciencesBeijing 100049People’s Republic of China

Wearable electronics are advancing towards miniaturization and ***,traditional energy supply methods have largely hindered their *** effective solution to this problem is to convert human mechanical energy into electricity to power wearable electronic ***,it is greatly attractive to design flexible,foldable and even stretchable energy harves.ing ***,we use the electros.inning and kirigami approach to develop a type of highly stretchable kirigami-patterned nanofiber-based triboelectric nanogenerator(K-TENG).Due to its.innovative structural design,the K-TENG can achieve a tensile strain of 220%,independent of the tensile properties of the material *** a person s.ings their arms,the K-TENG fixed to the clothing can convert mechanical energy from human movement into electrical *** produced electricity can directly drive 50 LED lights and a digital watch,or be stored in a lithium battery to charge the smartwatch and smartphone,*** study employs a new method to fabricate a stretchable triboelectric nanogenerator and demonstrates.its promising applications.in wearable power technology.

关键词： stretchable triboelectric nanogenerators kirigami energy harves.ing

Effects of s.il metal(loid)s pollution on microbial activities and environmental risks.in an abandoned chemical smelting site

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Journal of Environmental s.iences 2024年第9期143卷 60-70页

作者： Hao Li Jun Yao Jianli Liu ning Min Geoffrey sunahara Dongyang Men Robert Duran school of Water Resources and Environment Research Center of Environmental Science and EngineeringChina University of Geosciences(Beijing)Beijing 100083China Department of Natural Resource s.iences McGill University21111Lakeshore DriveSte-Anne-de-BellevueQuebecH9X 3V9Canada Equipe Environnement et Microbiologie MELODY groupUniversitéde Pau et des Pays de l’AdourE2S-UPPAIPREM UMR CNRS 5254BP 115564013 Pau CedexFrance

Abandoned chemical smelting sites containing toxic substances can seriously threaten and pose a risk to the surrounding ecological *** samples were collected from different depths(0 to 13 m)and analyzed for metal(loid)s content and fractionation,as well as microbial *** potential ecological risk indices for the different s.il depths(ordered from high to low)were:1 m(D-1)>surface(s-0)>5 m(D-5)>13 m(D-13)>9 m(D-9),ranging between 1840.65-13,089.62,and representing extremely high environmental risks,of which Cd(and probably not arsenic)contributed to the highest environmental risk.A modified combined pollution risk index(MCR)combining total content and mobile proportion of metal(loid)s,and relative toxicities,was used to evaluate the degree of contamination and potential environmental *** the near-surface samples(s-0 and D-1 layers),the MCR considered that As,Cd,Pb,sb,and Zn achieved high and alarming degrees of contamination,whereas Fe,Mn,and Ti were negligible or low to moderate pollution *** microcalorimetry and enzymatic activity measurements of contaminated s.il samples were used to assess the microbial metabolic activity *** analysis elucidated the relations.ip between metal(loid)s exchangeable fraction or content and microbial activity characteris.ics(picrobial metabolic activity in the D-1 layer was low presumably due to heavy metal *** activity indicators and microcalorimetric growth rate(k)measurements were considered sensitive indicators to reflect the s.il microbial activities.in abandoned chemical smelting sites.

关键词： Abandoned chemical smelting sites Microbial activities Modified combined pollution risk Microcalorimetry Enzymatic activities

Photomediated core modification of diaryl dihydrophenzines through three-component alkylarylation of alkenes toward organocatalyzed ATRP

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Green synthesis and Catalysis 2024年第1期5卷 35-41页

作者： Yajun Zhang Hao Wang Dandan Jiang Naixian sun Wei He Lili Zhao ning Qin ning Zhu Zheng Fang kai Guo College of Biotechnology and Pharmaceutical Engineering State Key Laboratory of Materials-Oriented Chemical EngineeringNanjing Tech UniversityNanjing211800China ins.itute of Advanced synthesis School of Chemistry and Molecular EngineeringNanjing Tech UniversityNanjing211800China Department of Mechanical Engineering The University of SheffieldSheffieldS13JDUnited Kingdom

The design and synthesis of a novel organic photocatalyst(OPC)have attracted broad interest from both the organic chemistry and polymer ***,we presented a visible-light-induced alkylarylation of alkenes strategy for core modification of 5,10-diaryl-5,10-dihydrophenazines(DADHPs)under metal-and additive-free conditions,with the aim to develop powerful photocatalyst for organocatalyzed atom transfer radical polymerization(O-ATRP).Good tolerance for a wide variety of functional groups and affording the corresponding tetrasubs.ituted products.in moderate to good yields were achieved in the batch and flow *** experimental and computational mechanis.ic study confirmed that DADHPs’radical cations andπ-πstacking interactions played important roles.in the alkylarylation of alkenes.A series of the tetrasubs.ituted DADHPs were directly synthesized from the corresponding noncore-modified phenazines,which were demonstrated to be effective organic photoredox catalysts for *** responsive nature,controlled polymerization manner,and welldefined poly(methyl methacrylate)were achieved via tetrasubs.ituted DADHPs mediated O-ATRP.

关键词： Photoinduced Core modification Diaryl dihydrophenzine O-ATRP

Quantum s.in Exchange interactions to Accelerate the Redox Kinetics.in Li–s Batteries

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Nano-Micro Letters 2024年第5期16卷 370-383页

作者： Yu Du Weijie Chen Yu Wang Yue Yu kai Guo Gan Qu Jianan Zhang Key Laboratory of Advanced Energy Catalytic and Functional Materials Preparation of Zhengzhou City College of Materials Science and EngineeringZhengzhou UniversityZhengzhou 450001People’s Republic of China

s.in-engineering with electrocatalysts have been exploited to suppress the“shuttle effect”in Li–s *** selec-tion,s.in-dependent electron mobility and s.in potentials.in activation barriers can be optimized as quantum s.in exchange interactions lead-ing to a significant reduction of the electronic repulsions.in the orbitals of ***,we anchor the MgPc molecules on fluorinated carbon nanotubes(MgPc@FCNT),which exhibits the single active Mg sites with axial *** to the density functional theory calculations,the electronic s.in polarization in MgPc@FCNT not only increases the adsorption energy toward LiPss.intermediates but also facilitates the tunneling process of electron in Li–s *** a result,the MgPc@FCNT provides an initial capacity of 6.1 mAh cm^(-2) even when the high sulfur loading is 4.5 mg cm^(-2),and s.ill maintains 5.1 mAh cm^(-2) after 100 *** work provides a new perspective to extend the main group single-atom catalysts enabling high-performance Li–s batteries.

关键词： Metal phthalocyanines s.in polarization Electrocatalysis Li–s batteries