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Defence Technology(防务技术) 2025年第1期43卷 120-141页

作者： Changjiang Liu Hujun Li Zhen Wang Yong he Guokai Zhang Mingyang Wang School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing 210094China State Key Laboratory of Disaster Prevention and Mitigation of Explosion and Impact People's Liberation Army Engineering UniversityNanjing 210014China

Traffic engineering such as tunnels in various altitudinal gradient zone are at risk of accidental explosion,which can damage personnel and *** prediction of the distribution pattern of explosive loads and shock wave propagation process in semi-enclosed structures at various altitude environment is key research focus in the fields of explosion shock and fluid *** effect of altitude on the propagation of shock waves in tunnels was investigated by conducting explosion test and numerical *** on the experimental and numerical simulation results,a prediction model for the attenuation of the peak overpressure of tunnel shock waves at different altitudes was *** results showed that the peak overpressure decreased at the same measurement points in the tunnel entrance under the high altitude *** contrast,an increase in altitude accelerated the propagation speed of the shock wave in the *** average error between the peak shock wave overpressure obtained using the overpressure prediction formula and the measured test data was less than15%,the average error between the propagation velocity of shock waves predicted values and the test data is less than 10%.The method can effectively predict the overpressure attenuation of blast wave in tunnel at various altitudes.

关键词： Shock wave propagation Tunnel Altitude effect Peak overpressure Shock waves velocity Engineering safety

Extraction of gravel characteristics and spatial inversion for ecological restoration monitoring in the Northern Tibetan Plateau

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Journal of Mountain Science 2025年第2期22卷 556-574页

作者： KONG Bo YU Huan QIU Xia HU Wenkai he Bing GUAN Xudong Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610041China College of Geography and Planning Chengdu University of TechnologyChengdu 610059China Tibet Geological Environment Monitoring Center Lhasa 850000China School of Computer Science Chengdu University of Information TechnologyChengdu 610225China Sichuan Real Estate Registration Center(Sichuan Provincial Land and Cadastral Affairs Center) Chengdu 610072China

Previous studies have often focused on monitoring grassland growth as the primary target of remote sensing investigations on grassland ecological restoration in the northern Tibetan Plateau,overlooking the crucial role played by gravel in the ecological restoration of these *** study utilizes supervised classification and segmentation techniques based on machine learning to extract gravel morphology profiles from field-sampled plot images and calculate their characteristic *** a multivariate linear approach combined with Principal Component Analysis(PCA),a model for inferring gravel characteristic parameters is *** features,particle size characteristics,and spatial distribution patterns of gravel are *** reveal that gravel predominantly exhibit sub-rounded shapes,with 80%classified as fine *** coefficients of determination(R2)between gravel particle size and coverage,perimeter,and area are 0.444,0.724,and 0.557,respectively,indicating linear *** cumulative contribution rate of the top five remote sensing factors is 95.44%,with the first geological factor contributing 77.64%,collectively reflecting the primary information of the 20 factors *** shows that areas with larger gravel particle sizes correspond to increased perimeter and *** in the Nagqu Prefecture of northern Tibet have a particle size range of 4-8 mm,primarily comprising fine gravel which accounts for 94.61%.These findings provide a scientific basis for extracting gravel characteristic parameters and understanding their spatial distribution variations in the northern Tibetan Plateau.

关键词： Gravel characteristics parameters Northern Tibetan Plateau Gravel outline extraction Remote sensing inversion Grassland degradation

Recent Strategies and Advances in Hydrogel‑Based Delivery Platforms for Bone Regeneration

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Nano-Micro Letters 2025年第3期17卷 389-439页

作者： Xiao Wang Jia Zeng Donglin Gan Kun Ling Mingfang he Jianshu Li Yongping Lu Scientific and Technological Innovation Center for Biomedical Materials and Clinical Research Guangyuan Key Laboratory of Multifunctional Medical HydrogelGuangyuan Central HospitalGuangyuan 628000People’s Republic of China Jiangsu Collaborative Innovation Center of Biomedical Functional Materials Jiangsu Key Laboratory of Bio‑Functional MaterialsSchool of Chemistry and Materials ScienceNanjing Normal UniversityNanjing 210023People’s Republic of China College of Polymer Science and Engineering State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu 610065People’s Republic of China

Bioactive molecules have shown great promise for effectively regulating various bone formation processes,rendering them attractive therapeutics for bone ***,the widespread application of bioactive molecules is limited by their low accumulation and short half-lives in *** have emerged as ideal carriers to address these challenges,offering the potential to prolong retention times at lesion sites,extend half-lives in vivo and mitigate side effects,avoid burst release,and promote adsorption under physiological *** review systematically summarizes the recent advances in the development of bioactive molecule-loaded hydrogels for bone regeneration,encompassing applications in cranial defect repair,femoral defect repair,periodontal bone regeneration,and bone regeneration with underlying ***,this review discusses the current strategies aimed at improving the release profiles of bioactive molecules through stimuli-responsive delivery,carrier-assisted delivery,and sequential ***,this review elucidates the existing challenges and future directions of hydrogel encapsulated bioactive molecules in the field of bone regeneration.

关键词： Hydrogel Bone regeneration Bioactive molecules Drug delivery Nano-/microscale carriers

Distributed Nash Equilibrium Seeking with Disturbances of Unknown Frequencies for High-Order Integrators over Jointly Strongly Connected Switching Networks

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Journal of Systems Science & Complexity 2025年第01期 369-389页

作者： he Xiongnan HUANG Jie Department of Mechanical and Automation Engineering The Chinese University of Hong Kong

In this paper, the authors study the problem of distributed Nash equilibrium seeking of N-player games with high-order integrator dynamics subject to disturbances generated by an uncertain exosystem. Similar problems have been studied for disturbances with an exactly known *** with the existing results of high-order integrator dynamics, which can only handle sinusoidal disturbances with known frequencies, this paper aims to handle multi-tone disturbances with unknown frequencies by introducing an adaptive control technique to estimate the unknown frequencies. Technically, when the exosystem is known, the disturbance can be dealt with by the Luenburger observer. In contrast, the Luenburger observer cannot deal with an uncertain exosystem. The authors combine the internal model design and some adaptive control technique to solve the proposed problem. Further, the authors also establish the sufficient condition to guarantee the convergence of the estimated unknown frequencies to the actual values of these frequencies. Two examples are given to verify the proposed algorithm.

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Research progress of catalysts for direct coal liquefaction

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Journal of Energy Chemistry 2025年第1期100卷 481-497页

作者： Wei Song Penggao Liu Xinyue Chen Ting Wang Chunrong he Rui Hao Kaiyu Liu State Key Laboratory of Chemistry and Utilization of Carbon Based Energy Resources College of ChemistryXinjiang UniversityUrumqi 830017XinjiangChina College of Chemistry and Chemical Engineering Henan Polytechnic UniversityJiaozuo 454003HenanChina Hunan Provincial Key Laboratory of Chemical Power Sources College of Chemistry and Chemical EngineeringCentral South UniversityChangsha 410083HunanChina

Coal direct liquefaction technology is a crucial contemporary coal chemical technology for efficient and clean use of coal resources. The development of direct coal liquefaction technology and the promotion of alternative energy sources are important measures to guarantee energy security and economic security. However, several challenges need to be addressed, including low conversion rate, inadequate oil yield, significant coking, demanding reaction conditions, and high energy consumption. Extensive research has been conducted on these issues, but further exploration is required in certain aspects such as pyrolysis of macromolecules during the liquefaction process, hydrogen activation, catalysts' performance and stability, solvent hydrogenation, as well as interactions between free radicals to understand their mechanisms better. This paper presents a comprehensive analysis of the design strategy for efficient catalysts in coal liquefaction, encompassing the mechanism of coal liquefaction, catalyst construction,and enhancement of catalytic conversion efficiency. It serves as a comprehensive guide for further research endeavors. Firstly, it systematically summarizes the conversion mechanism of direct coal liquefaction, provides detailed descriptions of various catalyst design strategies, and especially outlines the catalytic mechanism. Furthermore, it addresses the challenges and prospects associated with constructing efficient catalysts for direct coal liquefaction based on an understanding of their action mechanisms.

关键词： Direct coal liquefaction Catalysts Mechanismof action Solvent hydrogenation

Spatiotemporal characteristics and influencing factors of vegetation water use efficiency on the Tibetan Plateau in 2001–2020

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Journal of Geographical Sciences 2025年第1期35卷 39-64页

作者： he Chenyang WANG Yanjiao YAN Feng LU Qi School of Ecological and Environmental Science East China Normal UniversityShanghai200241China Institute of Ecological Conservation and Restoration Chinese Academy of ForestryBeijing100091China National Climate Center China Meteorological AdministrationBeijing100081China

Water use efficiency(WUE),as a pivotal indicator of the coupling degree within the carbon–water cycle of ecosystems,holds considerable importance in assessment of the carbon–water balance within terrestrial ***,in the context of global warming,WUE evolution and its primary drivers on the Tibetan Plateau remain *** study employed the ensemble empirical mode decomposition method and the random forest algorithm to decipher the nonlinear trends and drivers of WUE on the Tibetan Plateau in 2001–*** indicated an annual mean WUE of 0.8088 gC/mm·m^(2)across the plateau,with a spatial gradient reflecting decrease from the southeast toward the *** manifesting monotonous trends of increase or decrease in WUE accounted for 23.64%and 9.69%of the total,***,66.67%of the region exhibited trend reversals,i.e.,39.94%of the area of the Tibetan Plateau showed transition from a trend of increase to a trend of decrease,and 26.73%of the area demonstrated a shift from a trend of decrease to a trend of *** factors accounted for 70.79%of the variability in *** leaf area index and temperature served as the major driving forces of WUE variation.

关键词： water use efficiency spatiotemporal characteristic influencing factor Tibetan Plateau

健康公益传播网站首页设计的标准化语类分析——以器官捐献管理机构网站为例

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中国标准化 2025年第3期 162-167页

作者：田禾重庆邮电大学

本文以17个国家级捐献管理机构网站首页设计为研究对象,通过网络语类分析探究健康公益宣传网站首页如何通过语步实现建立信任、公益宣传、工作拓展等交际目标,讨论话语过程如何实现访客身份转变。建立公益健康宣传网站首页的语类模型,... 详细信息

本文以17个国家级捐献管理机构网站首页设计为研究对象,通过网络语类分析探究健康公益宣传网站首页如何通过语步实现建立信任、公益宣传、工作拓展等交际目标,讨论话语过程如何实现访客身份转变。建立公益健康宣传网站首页的语类模型,并对比分析我国网站,就其首页内容设计的提质增效工作进行讨论。

关键词：健康公益宣传网络语类分析网站首页设计器官捐献宣传

Ultrahigh Energy and Power Density in Ni-Zn Aqueous Battery via Superoxide-Activated Three-Electron Transfer

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Nano-Micro Letters 2025年第4期17卷 63-76页

作者： Yixue Duan Bolong Li Kai Yang Zheng Gong Xuqiao Peng Liang he Derek Ho School of Mechanical Engineering State Key Laboratory of Intelligent Construction and Healthy Operation and Maintenance of Deep Underground EngineeringSichuan UniversityChengdu 610065People’s Republic of China Department of Materials Science and Engineering City University of Hong KongKowloonHong Kong 999077People’s Republic of China Hong Kong Centre for Cerebro-Cardiovascular health Engineering Hong Kong Science ParkHong Kong 999077People’s Republic of China School of Mechanical Engineering Sichuan UniversityChengdu 610065People’s Republic of China

Aqueous Ni-Zn microbatteries are safe,reliable and inexpensive but notoriously suffer from inadequate energy and power ***,we present a novel mechanism of superoxide-activated Ni substrate that realizes the redox reaction featuring three-electron transfers(Ni↔Ni3+).The superoxide activates the direct redox reaction between Ni substrate and KNiO_(2)by lowering the reaction Gibbs free energy,supported by in-situ Raman and density functional theory *** prepared chronopotentiostatic superoxidation-activated Ni(CPS-Ni)electrodes exhibit an ultrahigh capacity of 3.21 mAh cm^(-2)at the current density of 5 mA cm^(-2),nearly 8 times that of traditional one-electron processes *** under the ultrahigh 200 mA cm^(-2)current density,the CPS-Ni electrodes show 86.4%capacity retention with a Columbic efficiency of 99.2%after 10,000 *** CPS-Ni||Zn microbattery achieves an exceptional energy density of 6.88 mWh cm^(-2)and power density of 339.56 mW cm^(-2).Device demonstration shows that the power source can continuously operate for more than 7 days in powering the sensing and computation intensive practical application of photoplethysmographic waveform *** work paves the way to the development of multi-electron transfer mechanisms for advanced aqueous Ni-Zn batteries with high capacity and long lifetime.

关键词： Superoxide Multiple electron transfer Ni aqueous battery AIoT power source Wearable health monitoring

long-term trends and response of wet ammonia deposition to changes in anthropogenic emissions in the Pearl River delta of China

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Journal of Environmental Sciences 2025年第5期151卷 373-386页

作者： Mingyue Li Lyumeng Ye Ming Chang Weihua Chen Shuidi he Buqing Zhong Xuemei Wang Guangdong-Hongkong-Macao Joint Laboratory of Collaborative Innovation for Environmental Quality Institute for Environmental and Climate ResearchJinan UniversityGuangzhou 511443China South China Institute of Environmental Sciences The Ministry of Ecology and Environment of PRCGuangzhou 510530China Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems South China Botanical GardenChinese Academy of SciencesGuangzhou 510650China

The Pearl River Delta(PRD)region has been identified as a significant hotspot of wet ammonium ***,the absence of long-term monitoring data in the area hinders the comprehension of the historical trends and changes in wet NH_(4)^(+)-N deposition in response to emissions,which interferes with the ability to make effective *** study has analyzed the long-term trends of wet NH_(4)^(+)-N deposition flux and has quantified the effect of anthropogenic emissions and meteorological factors at a typical urban site and a typical forest site in the PRD region from 2009 to *** revealed a significant decreasing trend in wet NH_(4)^(+)-N flux in both the typical urban and forest areas of the PRD region,at-6.2%/year(phe wet NH_(4)^(+)-N deposition trend over the past 12 years compared to meteorological *** conditions dominated the interannual fluctuations in wet NH_(4)^(+)-N deposition with an absolute contribution of 46%–52%,while anthropogenic emissions change alone explained 10%–31%.NH_(3)emissions have the greatest impact on the urban area among anthropogenic emission factors,while SO_(2)emissions have the greatest impact on the forest ***,precipitation was identified as the primary meteorological driver for both *** findings also imply that the benefits of NH_(3)emissions reductions might not immediately emerge due to interference from weather-related factors.

关键词： long-term trends Inter-annual variation Wet ammonium deposition Anthropogenic emission change Meteorological condition The Pearl River Delta region

Light Use Efficiency Model Based on Chlorophyll Content Better Captures Seasonal Gross Primary Production Dynamics of Deciduous Broadleaf Forests

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Chinese Geographical Science 2025年第1期35卷 55-72页

作者： YANG Rongjuan LIU Ronggao LIU Yang CheN Jingming XU Mingzhu he Jiaying State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory for Humid Subtropical Ecogeographical Processes of the Ministry of Education School of Geographical SciencesFujian Normal UniversityFuzhou 350007China Department of Geography and Planning University of TorontoTorontoON M5S 3G3Canada

Gross primary production(GPP)is a crucial indicator representing the absorption of atmospheric CO_(2) by *** present,the estimation of GPP by remote sensing is mainly based on leaf-related vegetation indexes and leaf-related biophysical para-meter leaf area index(LAI),which are not completely synchronized in seasonality with *** this study,we proposed chlorophyll content-based light use efficiency model(CC-LUE)to improve GPP estimates,as chlorophyll is the direct site of photosynthesis,and only the light absorbed by chlorophyll is used in the photosynthetic *** CC-LUE model is constructed by establishing a linear correlation between satellite-derived canopy chlorophyll content(Chlcanopy)and *** method was calibrated and validated utiliz-ing 7-d averaged in-situ GPP data from 14 eddy covariance flux towers covering deciduous broadleaf forest ecosystems across five dif-ferent climate *** showed a relatively robust seasonal consistency between Chlcanopy with GPP in deciduous broadleaf forests under different climatic *** CC-LUE model explained 88% of the in-situ GPP seasonality for all validation site-year and 56.0% of in-situ GPP variations through the growing season,outperforming the three widely used LUE models(MODIS-GPP algorithm,Vegetation Photosynthesis Model(VPM),and the eddy covariance-light use efficiency model(EC-LUE)).Additionally,the CC-LUE model(RMSE=0.50 g C/(m^(2)·d))significantly improved the underestimation of GPP during the growing season in semi-arid region,re-markably decreasing the root mean square error of averaged growing season GPP simulation and in-situ GPP by 75.4%,73.4%,and 37.5%,compared with MOD17(RMSE=2.03 g C/(m^(2)·d)),VPM(RMSE=1.88 g C/(m^(2)·d)),and EC-LUE(RMSE=0.80 g C/(m^(2)·d))*** chlorophyll-based method proved superior in capturing the seasonal variations of GPP in forest ecosystems,thereby provid-ing the possibility of a more precise depiction of forest seasonal carbon uptake.

关键词： canopy chlorophyll content(Chlcanopy) photosynthesis gross primary production(GPP) light use efficiency(LUE)model seasonal dynamics deciduous broadleaf forest(DBF)

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