检索结果-南通市图书馆

在线全文

学校读者我要写书评

暂无评论

基于纵横比自适应的相关滤波跟踪算法

电子学报 2024年第6期52卷 2112-2122页

作者：钟钰彬杨鹏窦磊南京理工大学瞬态物理国家重点实验室江苏南京210094

由于跟踪过程目标不规则形变的影响,采用固定纵横比的尺度模型无法精确地估计目标的尺度.为解决该问题,本文提出基于纵横比自适应的相关滤波跟踪算法.基于fDSST(fast Discriminative Scale Space Tracking)算法,训练学习纵横比模型,更... 详细信息

由于跟踪过程目标不规则形变的影响,采用固定纵横比的尺度模型无法精确地估计目标的尺度.为解决该问题,本文提出基于纵横比自适应的相关滤波跟踪算法.基于fDSST(fast Discriminative Scale Space Tracking)算法,训练学习纵横比模型,更新目标的纵横比,获取更精确的目标尺度.在此基础上,本文设计了平滑修正方案以及学习率自适应机制,可以有效地缓解因目标出现遮挡导致的模型漂移问题.在OTB100、VOT2016和VOT2018数据集上与其他跟踪算法进行对比实验,结果表明本文算法改善了基准算法的性能,特别是在OTB100上的总体准确率和成功率比fDSST提高了9.6%和6.2%.

关键词：目标跟踪相关滤波纵横比尺度估计平滑修正学习率自适应

Luminescent metal-halide perovskites:fundamentals,synthesis,and light-emitting devices

在线全文

学校读者我要写书评

暂无评论

Science China Chemistry 2024年第6期67卷 1776-1838页

作者： Kang Wang Jeong Hui Kim Jie Yang Xiaoke Liu Yixuan dou Yuxuan Li Weijian Tao Haiyun Dong Haiming Zhu Kaifeng Wu Li Na Quan Feng Gao Jianpu Wang Letian dou Yong Sheng Zhao Beijing National Laboratory for Molecular Sciences(BNLMS) Key Laboratory of PhotochemistryInstitute of ChemistryChinese Academy of SciencesBeijing100190China Davidson School of Chemical Engineering Purdue UniversityWest LafayetteIN47907USA School of Chemical Sciences University of Chinese Academy of SciencesBeijing100049China Key Laboratory of Flexible Electronics(KLOFE) Institute of Advanced Materials(IAM)&School of Flexible Electronics(Future Technologies)Nanjing Tech University(NanjingTech)Nanjing211816China Department of Physics Linköping UniversityLinköping58183Sweden Department of Chemistry Virginia TechBlacksburgVA24060USA State Key Laboratory of Molecular Reaction Dynamics Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian116023China Department of Chemistry Zhejiang UniversityHangzhou310058China Changzhou University Changzhou213164China Department of Chemistry Purdue UniversityWest LafayetteIN47907USA

Metal-halide perovskites have garnered considerable research attention as highly efficient light emitters in recent years due to their outstanding optoelectronic properties with remarkable tunability and excellent solution *** advancements have been achieved in the development of novel halide perovskites,and the exploitations of these materials in lightemitting *** review comprehensively outlines recent breakthroughs in metal-halide perovskites,encompassing the rational design of perovskite materials with tunable light emission properties,the controllable growth of single crystal for a deeper understanding of their structure-property relationships,as well as the fundamental insights into the photophysics and carrier dynamics in perovskite ***,it provides an overview of recent applications of perovskite materials in high-performance light-emitting diodes(LEDs)and lasers.

关键词： metal-halide perovskites perovskite luminescent materials perovskite synthesis excited-state processes perovskite light-emitting diodes perovskite lasers

CO_(2) corrosion of X80 steel welded joints under micro-turbulence induced by welding reinforcement height

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2024年第4期31卷 1015-1032页

作者： Xiao-hui dou Bin Li Zong-hao He Xin-wei Zhang Da-lei Zhang Yan Li School of Materials Science and Engineering China University of Petroleum(East China)Qingdao 266580ShandongChina School of Energy and Power Engineering Jiangsu UniversityZhenjiang 212013JiangsuChina

Corrosion failure accidents owing to flow erosion and pipeline corrosion frequently occur during *** welding reinforcement height(WRH)can induce locally micro-turbulent flow field,which aggravates local corrosion of welded joints.A high wall shear stress(WsS)experimental setup was established to conduct the online electrochemical corrosion *** influence of WRH sizes on local corrosion of welded joints was studied at different flow *** electrochemical signals of the local corrosion of X80 welded joints at different flow rates were monitored in real time using electrochemical impedance spectroscopy and wire beam *** addition,the corrosion products composition and properties were *** results show that the micro-turbulent flow fields induced by the WRHs can enhance ion mass transfer near the welded *** corrosion products on the WRH surface also present different microscopic morphologies at different flow *** strong flow fields,the locally enhanced wsS can peel off the dense corrosion product partially,leading to the electrochemical distribution of large cathode and small anode,which accelerates the occurrence and development processes of the local corrosion of welded *** scientific guidelines for the corrosion protection of long-distance oil and gas pipelines can be potentially provided.

关键词： X80 steel welded joint Welding reinforcement height Micro-turbulence CO_(2)corrosion-Ion mass transfer

Wave Attenuation and Turbulence Driven by Submerged Vegetation Under Current-Wave Flow

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

China Ocean Engineering 2024年第4期38卷 602-611页

作者： HUANG Yu-ming Ding Lei WANG Yi-fei CHEN Ben YANG Xiao-yu dou Xi-ping School of Water Resources and Hydropower Engineering Wuhan UniversityWuhan430072China Key Laboratory of Port Waterway and Sedimentation Engineering of MOTNanjing Hydraulic Research InstituteNanjing 210029China

A set of laboratory experiments are carried out to investigate the effect of following/opposing currents on wave *** vegetation canopies with aligned and staggered configurations were tested under the condition of various regular wave heights and current velocities,with the constant water depth being 0.60 m to create the desired submerged *** show that the vegetation-induced wave dissipation is enhanced with the increasing incident wave height.A larger velocity magnititude leads to a greater wave height attenuation for both following and opposing current ***,there is a strong positive linear correlation between the damping coefficientβand the relative wave height H_(0)/h,especially for pure wave *** the velocity profile,the distributions of U_(min)and U_(max)show different patterns under combined wave and *** time-averaged turbulent kinetic energy(TKE)vary little under pure wave and U_(c)=±0.05 m/s *** the increase of flow velocity amplitude,the time-averaged TKE shows a particularly pronounced increase trend at the top of the *** vegetation drag coefficients are obtained by a calibration *** empirical relations of drag coefficient with Reynolds and Keulegane-Carpenter numbers are proposed to further understand the wave-current-vegetation interaction mechanism.

关键词： wave attenuation rigid vegetation following and opposing currents turbulent kinetic energy

Responses of nitrogen cycling and related microorganisms to brackish wetlands formed by evapotranspiration

在线全文

学校读者我要写书评

暂无评论

Pedosphere 2024年第1期34卷 252-266页

作者： Jiaohui FANG Tianshu LU Jian LIU Shangbin HE Xiufeng YANG Huashan dou Honghai ZHANG School of Life Sciences Qufu Normal UniversityQufu 273100China Environment Research Institute Shandong UniversityQingdao 266237China Hulunbuir Academy of Inland Lakes in Northern Cold&Arid Areas Hulunbuir 021000China

Elevated evapotranspiration due to warmer air temperature could raise salinity and nutrient levels of some inland wetlands, potentially impacting nitrogen cycling. To characterize the impact of high evapotranspiration on soil microbial nitrogen cycling in inland wetlands, we compared freshwater and brackish marsh(or non-marsh) wetlands in terms of sediment ammonia-oxidizing rate(AOR), denitrifying rate(DR), and related microbial communities in a typical inland basin, the Hulun Lake basin, in China. Results showed that marsh ecosystems(ME) exhibited 31% higher AOR and 65% higher DR than non-marsh ecosystems(NE). For NE, freshwater non-marsh wetland exhibited 12% higher AOR than brackish non-marsh wetland. This was probably due to the inhibitory effects of high NH_4~+ and salinity levels on ammonia-oxidizing archaea in brackish non-marsh wetland. Conversely, DR in brackish non-marsh wetland was 23% higher than that in freshwater non-marsh wetland, with total organic carbon(TOC) significantly influencing this difference,suggesting that the higher DR in brackish non-marsh wetland was mainly due to its higher TOC level. For ME, due to the direct and indirect interference of salinity, brackish marsh wetland displayed 26% lower AOR and 19% lower DR than freshwater marsh wetland. Besides, brackish wetlands harbored distinct ammonia-oxidizing and denitrifying microbial communities compared to freshwater wetlands. The assembly of these communities was dominated by stochastic processes, while brackish wetlands exhibited more prominent deterministic processes than freshwater wetlands. Overall, high evapotranspiration altered activities and community characteristics of ammonia oxidizers and denitrifiers in inland brackish wetlands by enhancing salinity and nutrient levels,while emergent plants occurring in ME could mitigate the adverse effects of salt stress of inland brackish wetlands on nitrogen cycling.

关键词： ammonia-oxidizing archaea ammonia-oxidizing bacteria aquatic plants denitrifying bacteria nitrogen transformation inland wetlands

Evaluation of erastin synergized cisplatin anti-nasopharyngeal carcinoma effect with a glutathione-activated near-infrared fluorescent probe

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2024年第2期35卷 311-316页

作者： Rong He Dandan Tang Ningge Xu Heng Liu Kun dou Xuejun Zhou Fabiao Yu Department of Otolaryngology Head and Neck SurgeryThe First Affiliated Hospital of Hainan Medical UniversityHaikou 570102China Key Laboratory of Hainan Trauma and Disaster Rescue Key Laboratory of Emergency and TraumaMinistry of EducationEngineering Research Center for Hainan Bio-Smart Materials and Bio-Medical DevicesCollege of Emergency and TraumaHainan Medical UniversityHaikou 571199China Sichuan Provincial General Hospital of Judicial Police Chengdu 610225China

Nasopharyngeal carcinoma(NPC),a malignant tumor originating from the nasopharynx,is one of the common malignant tumors of the head and *** are significant geographical differences in the incidence of nasopharyngeal carcinoma,with a high incidence in China and Southeast Asian ***,we designed and synthesized a novel near-infrared fluorescent(NIRF)probe to detect glutathione(GSH)in cellular and tumor environments using semi-naphthofluorescein(SNAFL)as the fluorescent molecular backbone and 2-fluoro-4-nitrobenzenesulfonate as the recognition *** reaction with GSH,SNAFL-GSH emitted a fluorescence signal,and its emission wavelength at 650 nm was remarkably *** results of selectivity experiments indicated that SNAFL-GSH was able to discriminate GSH from Cys,Hcy,and H_(2) ***,SNAFL-GSH could image both endogenous and exogenous GSH and distinguish normal and cancer cells by fluorescence signal *** the cellular level,cisplatin(DDP)-induced ferroptosis and inhibition of proliferation of various NPC cell lines(CNE2,CNE1,5-8F cells)by erastin combined with DDP were visualized with the help of *** a mouse tumor xenograft model,we successfully employed SNAFL-GSH for the evaluation of the efficacy of erastin combined with DDP in the treatment of *** importantly,the probe could image cancerous tissue sections from NPC patients with an imaging depth of approximately 80µ*** was foreseen that SNAFL-GSH offered great potential for application in the diagnosis and evaluation of the therapeutic efficacy of NPC,and these results would also provide new ideas for the clinical treatment of NPC.

关键词： Glutathione NIRF probe Ferroptosis Anti-tumor therapy evaluation Bioimaging

The first factor affecting dryland winter wheat grain yield under various mulching measures: Spike number

在线全文

学校读者我要写书评

暂无评论

Journal of Integrative Agriculture 2024年第3期23卷 836-848页

作者： Yingxia dou Hubing Zhao Huimin Yang Tao Wang Guanfei Liu Zhaohui Wang Sukhdev Malhi Coliege of Natural Resources and Environment Northwest A&F UniversityYangling 712100China Key Laboratory of Plant Nutrition and the Agri-Environment in Northwest China Ministry of Agriculture and Rural AffairsYangling 712100China Department of Renewable Resources University of AlbertaEdmonton T6G 2H1Canada

Water is the key factor limiting dryland wheat grain *** affects crop yield and yield components by affecting soil *** research is needed to determine the relationships between yield components and soil moisture with yield,and to identify the most important factor affecting grain yield under various mulching measures.A long-term 9-yearifeld experiment in the Loess Plateau of Northwest China was carried out with three treatments:no mulch (CK),plastic mulch (M_(P)) and straw mulch (M_(S)).Yield factors and soil moisture were measured,and the relationships between them were explored by correlation analysis,structural equation modeling and significance *** results showed that compared with CK,the average grain yields of M_(P) and M_(S) increased by 13.0and 10.6%,*** average annual grain yield of the M_(P) treatment was 134 kg ha^(–1) higher than the M_(S) *** were no significant differences in yield components among the three treatments (P<0.05).Soil water storage of the M_(S) treatment was greater than the M_(P) treatment,although the differences were not statistically *** water storage during the summer fallow period (SWSSF) and soil water storage before sowing (SWSS) of M_(S) were significantly higher than in CK,which increased by 38.5 and 13.6%,*** relationship between M_(P) and CK was not statistically significant for SWSSF,but the SWSS in M_(P) was significantly higher than in *** terms of soil water storage after harvest (SWSH) and water consumption in the growth period(ET),there were no signi?cant differences among the three *** on the three analysis methods,we found that spike number and ET were positively correlated with grain ***,the relative importance of spike number to yield was the greatest in the M_(P )and M_(S) treatments,while that of ET was the greatest in *** SWSSF could indirectly increase spike number and ET in the three treatments.B

关键词： dryland winter wheat plastic mulch spike number straw mulch

Effect of temperature and reaction path interaction on fluidization reduction kinetics of iron ore powder

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2024年第8期31卷 1840-1849页

作者： Guo-min Zhu Ming-wei Hu An-nan dou Jin-yu Huang Jing Ding Qi-yan Xu School of Metallurgical Engineering Anhui University of TechnologyMa'anshan 243002AnhuiChina

Due to the instability of FeO at temperatures below 843 K,the fuidization reduction pathway of iron ore powder changes with the reduction ***,the effect of temperature and reaction pathway interaction on the kinetics of fuidization reduction of iron ore powder under low-temperature conditions ranging from 783 to 903 K was investigated to describe the fluidization reduction rate of iron ore powder from three aspects:microstructure change,reaction limiting link,and apparent activation energy of the reaction,exploring their internal *** experimental results revealed that in a temperature range of 783-813 K,the formation of a dense iron layer hindered the internal diffusion of reducing gas,resulting in relatively high gas diffusion *** addition,due to the differences in limiting links and reaction pathways in the intermediate stage of reduction,the apparent activation energy of the reaction *** apparent activation energy of the reaction ranged from 23.36 to 89.13 kJ/mol at temperature ranging from 783 to 813 K,while it ranged from 14.30 to 68.34 kJ/mol at temperature ranging from 873 to 903 K.

关键词： Reaction limiting link Gas internal diffusion Interface reaction Apparent activation energy Iron ore powder Reaction pathway Fluidization reduction

Late-stage modification of bioactive compounds:Improving druggability through efficient molecular editing

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Pharmaceutica Sinica B 2024年第3期14卷 1030-1076页

作者： Tongyu Huo Xinyi Zhao Zengrui Cheng Jialiang Wei Minghui Zhu Xiaodong dou Ning Jiao State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical SciencesPeking UniversityBeijing 100191China Changping Laboratory Beijing 102206China Shanghai Key Laboratory of Green Chemistry and Chemical Processes East China Normal UniversityShanghai 200062China

Synthetic chemistry plays an indispensable role in drug discovery,contributing to hit compounds identification,lead compounds optimization,candidate drugs preparation,and so *** Nobel Prize laureate James Black emphasized,“the most fruitful basis for the discovery of a new drug is to start with an old drug”***-stage modification or functionalization of drugs,natural products and bioactive compounds have garnered significant interest due to its ability to introduce diverse elements into bioactive compounds *** modifications alter the chemical space and physiochemical properties of these compounds,ultimately influencing their potency and *** enrich a toolbox of chemical modification methods for drug discovery,this review focuses on the incorporation of halogen,oxygen,and nitrogen—the ubiquitous elements in pharmacophore components of the marketed drugs—through late-stage modification in recent two decades,and discusses the state and challenges faced in these *** also emphasize that increasing cooperation between chemists and pharmacists may be conducive to the rapid discovery of new activities of the functionalized ***,we hope this review would serve as a valuable resource,facilitating the application of late-stage modification in the construction of novel molecules and inspiring innovative concepts for designing and building new drugs.

关键词： Late-stage modification Drug space Halogenation Oxygenation Nitrogenation Synthetic chemistry