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Chinese Journal of Chemistry 2013年第3期31卷 321-328页

作者： Ting-Shun zhu Ming-hua xu Shanghai Institute of Materia Medica Chinese Academy of Sciences Shanghai 201203 China

Simple and readily available chiral N-（sulfinyl）allylamines have been developed as efficient novel ligands for the rhodium-catalyzed enantioselective 1,2-addition of arylboronic acids to challenging aliphatic a-ketoesters. By employing the linear or branched sulfinamide-olefin ligands, interesting enantioselectivity as well as regioselectiw ity reversal in the related asymmetric additions were observed.

关键词： asymmetric catalysis rhodium sulfur-o|efin ligand 1,2-addition stereoselectivity reversal

New insight into the origin and evolution of the flora and fauna of Hainan Island, China

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Science China Earth Sciences 2025年第1期68卷 52-61页

作者： hua zhu Center for Integrative Conservation Xishuangbanna Tropical Botanical Garden Chinese Academy of Sciences Yunnan International Joint Laboratory of Southeast Asia Biodiversity Conservation Yunnan Key Laboratory for the Conservation of Tropical Rainforests and Asian Elephants

The origin of the biota of Hainan Island, China, remains a fundamental scientific problem. Comparative studies on the biota, geological tectonics, and paleomagnetism proposed that during the Eocene, Hainan Island connected Vietnam and Guangxi, and then moved to the southeast to reach its present location. This review mainly discusses its biota origin from molecular phylogeny and palaeobotanical research. The formation and evolution of the biological groups of Hainan Island were identified via research on their genomes, phylogeny, and molecular biogeography. This research showed that the genera and species that appeared and diverged early in their evolution(i.e., before the Miocene) can be explained by the land connection between Hainan Island, Vietnam, and Guangxi during the Eocene-Oligocene. According to Southeast Asian tectonic theory, in the Middle Miocene(at about 15 million years ago), Hainan Island had moved to its present position. The population and genetic divergence of species with late divergence times(after 15 Ma) can be reasonably explained by the close proximity(or land connection) between Hainan Island and the Leizhou Peninsula, enabling genetic communication between Hainan Island and the Chinese mainland, but have exceptional cases. Conclusions have been obtained through palaeobotanical studies, showing that in the Eocene-Oligocene period, southwest China and Hainan Island had subtropical vegetation and flora. However, the fossil group in southeast China(in Maoming, near present-day Hainan Island) in the Late Eocene indicated a tropical rainforest vegetation and flora. This suggests that in the Paleogene, Hainan Island may have been located near or on the southwest border of Guangxi and northern Vietnam, rather than in its present location. The floristic division of the flora of Hainan Island basically presents a northeast-southwest inclined distribution pattern. This pattern can be explained by the counterclockwise rotation of Hainan Island during i

关键词： Molecular phylogeny Biogeography Paleobotany Origin of flora and fauna Hainan Island of China

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TEMPERATURE PROGRAMMED DESORPTION AND THERMAL DECOMPOSITION OF n-BUTYLAMINE ON ZEOLITE HZSM-5

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Chinese Science Bulletin 1989年第5期34卷 384-389页

作者：朱建华须沁华 Department of Chemistry Nanking University

Ⅰ. NTRODUCTIONIn order to explain the catalytic properties of zeolite HZSM-5, it is necessary to know the nature, number and strength distribution of acid sites of zeolite, and the temperature programmed desorption (... 详细信息

关键词： zeolite HZSM-5 TPD n-butylamine.

Development of an automatic monitoring system for rice light-trap pests based on machine vision

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Journal of Integrative Agriculture 2020年第10期19卷 2500-2513页

作者： YAO Qing FENG Jin TANG Jian xu Wei-gen zhu xu-hua YANG Bao-jun LU Jun XIE Yi-ze YAO Bo WU Shu-zhen KUAI Nai-yang WANG Li-jun School of Information Science and Technology Zhejiang Sci-Tech UniversityHangzhou 310018P.R.China State Key Laboratory of Rice Biology China National Rice Research InstituteHangzhou 310006P.R.China Plant Protection Quarantine and Pesticide Management Station of ZhejiangHangzhou 310020P.R.China Zhejiang Top Cloud-agri Technology Co Ltd.Hangzhou 310015P.R.China Agricultural Technology Extension Center of Shangyu Shaoxing 312300P.R.China Agricultural Technology Extension Center of Keerqin Keerqin 137713P.R.China

Monitring pest populations in paddy fields is important to effectively implement integrated pest *** traps are widely used to monitor field pests all over the *** conventional light traps still involve manual identification of target pests from lots of trapped insects,which is time-consuming,labor-intensive and error-prone,especially in pest peak *** this paper,we developed an automatic monitoring system for rice light-trap pests based on machine *** system is composed of an itelligent light trap,a computer or mobile phone client platform and a cloud *** light trap firstly traps,kills and disperses insects,then collects images of trapped insects and sends each image to the cloud *** target pests in images are automatically identifed and counted by pest identification models loaded in the *** avoid light-trap insects piling up,a vibration plate and a moving rotation conveyor belt are adopted to disperse these trapped *** was a close correlation(r=0.92)between our automatic and manual identification methods based on the daily pest number of one-year images from one light *** experiments demonstrated the effectiveness and accuracy of our automatic light trap monitoring system.

关键词： automatic monitoring system light trap rice pest machine vision image processing convolutional neural network

SEFormer:A Lightweight CNN-Transformer Based on Separable Multiscale Depthwise Convolution and Efficient Self-Attention for Rotating Machinery Fault Diagnosis

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Computers, Materials & Continua 2025年第1期82卷 1417-1437页

作者： Hongxing Wang Xilai Ju hua zhu huafeng Li State Key Laboratory of Mechanics and Control for Aerospace Structures Nanjing University of Aeronautics and AstronauticsNanjing210016China School of Computer Science and Engineering Nanyang Technological UniversitySingapore639798Singapore

Traditional data-driven fault diagnosis methods depend on expert experience to manually extract effective fault features of signals,which has certain ***,deep learning techniques have gained prominence as a central focus of research in the field of fault diagnosis by strong fault feature extraction ability and end-to-end fault diagnosis ***,utilizing the respective advantages of convolution neural network(CNN)and Transformer in local and global feature extraction,research on cooperating the two have demonstrated promise in the field of fault ***,the cross-channel convolution mechanism in CNN and the self-attention calculations in Transformer contribute to excessive complexity in the cooperative *** complexity results in high computational costs and limited industrial *** tackle the above challenges,this paper proposes a lightweight CNN-Transformer named as SEFormer for rotating machinery fault ***,a separable multiscale depthwise convolution block is designed to extract and integrate multiscale feature information from different channel dimensions of vibration ***,an efficient self-attention block is developed to capture critical fine-grained features of the signal from a global ***,experimental results on the planetary gearbox dataset and themotor roller bearing dataset prove that the proposed framework can balance the advantages of robustness,generalization and lightweight compared to recent state-of-the-art fault diagnosis models based on CNN and *** study presents a feasible strategy for developing a lightweight rotating machinery fault diagnosis framework aimed at economical deployment.

关键词： CNN-Transformer separable multiscale depthwise convolution efficient self-attention fault diagnosis

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运动平台上多基地雷达时间同步技术

系统工程与电子技术 2005年第10期27卷 1734-1737页

作者：陈伯孝朱旭花张守宏西安电子科技大学雷达信号处理国家重点实验室陕西西安710071

常规双/多基地雷达在收站和发站之间采用一定的物理链路进行同步,但如果收站或发站在运动平台上,就不能建立这样的通信链路。为此,研究了在运动平台上的双/多基地雷达的时间同步方法。该雷达采用调频中断连续波(FMICW)信号,时间同步包... 详细信息

常规双/多基地雷达在收站和发站之间采用一定的物理链路进行同步,但如果收站或发站在运动平台上,就不能建立这样的通信链路。为此,研究了在运动平台上的双/多基地雷达的时间同步方法。该雷达采用调频中断连续波(FMICW)信号,时间同步包括调制脉冲的同步和调制频率的同步。在接收站对直达波进行检测和跟踪,再经非相干积累、滤波、谱分析等处理来提取同步信号,分析其性能。计算机仿真结果验证了这种方法的可行性。

关键词：多基地雷达时间同步直达波运动平台

Rapid and scalable preparation of highly quaternized polymer networks to achieve efficient simultaneous adsorption of iodide and pertechnetate

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Science China Chemistry 2025年第1期68卷 337-349页

作者： Meiyun xu Song Gu Fulong Chen Zhe Zhao Peng Liu Daoben hua State Key Laboratory of Radiation Medicine and Protection School of Radiological and Interdisciplinary Sciences (RAD-X) Collaborative Innovation Center of Radiological Medicine of Jiangsu Higher Education Institutions Soochow University

The efficient separation of fission products,such as TcO4-and I-,holds strategic significance for the management of radioactive wastes and environmental *** this study,we propose an ultrafast strategy for scalable preparation of a highly quaternized organic network to facilitate efficient and synchronous separation of iodide and *** network can be prepared within a few minutes at room temperature,using polyethylenimine and 1,2,4,5-tetrakis（bromomethyl）benzene as building *** chlorine replacement,the network,abundantly decorated with quaternary ammonium groups （Cl@QPN）,exhibits an ultrahigh positive charge density of 7.6 mmol/*** enables the rapid and efficient enrichment of target anions through strong electrostatic Coulomb *** a result,Cl@QPN exhibits significantly higher adsorption rate constants of 0.830 g/（mg min） for ReO4-（a nonradioactive surrogate of TcO4-） and 0.677 g/（mg min） for I-compared to other ***,it possesses high adsorption capacities,reaching 1,681 mg/g for ReO4-and 917.4 mg/g for I-.Cl@QPN also demonstrates good selectivity towards target ions and shows efficient adsorption for99TcO4-.Additionally,Cl@QPN exhibits high dynamic processing capacities,handling up to 3,100 and 7,400 kg of simulated streams per kilogram of material for I-and ReO4-,respectively.

关键词： quaternized polymer networks adsorption pertechnetate iodide liquid radioactive streams

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福建治理互花米草试验研究

海洋环境科学 2010年第5期29卷 767-769页

作者：许珠华福建省海洋环境与渔业资源监测中心福建福州350003

针对外来入侵植物互花米草在福建沿海滩涂蔓延,制约沿海经济、社会和环境的可持续发展,采用"滩涂互花米草除控制"稀释液喷湿互花米草的茎叶,15 d后互花米草的茎叶由绿转淡黄,30 d后逐渐枯死,60 d后根系开始枯烂,180 d后彻底灭除,同时无... 详细信息

针对外来入侵植物互花米草在福建沿海滩涂蔓延,制约沿海经济、社会和环境的可持续发展,采用"滩涂互花米草除控制"稀释液喷湿互花米草的茎叶,15 d后互花米草的茎叶由绿转淡黄,30 d后逐渐枯死,60 d后根系开始枯烂,180 d后彻底灭除,同时无萌芽再生。经检测,"滩涂互花米草除控制剂"低毒,可溶于水,在海水、沉积物和贝类体内未检出残留物。利用"滩涂互花米草除控制剂"治理互花米草环境安全、简便、快捷、彻底。

关键词：治理互花米草试验研究福建海域

Rock fracture mechanism of buffer blasting with cushion layer at the borehole bottom

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 325-334页

作者： Xinguang zhu Chenxi Ding Zhe Sui Hong Su xu Guo School of Civil and Resources Engineering University of Science and Technology BeijingBeijing 100083China Key Laboratory for Mechanics in Fluid Solid Coupling Systems Institute of MechanicsChinese Academy of SciencesBeijing 100190China School of Mechanics and Civil Engineering China University of Mining and Technology(Beijing)Beijing 100083China School of Chemical and Blasting Engineering Anhui University of Science and TechnologyHuainan 232001China

This study primarily investigates the rock fracture mechanism of bottom cushion layer blasting and explores the effects of the bottom cushion layer on rock *** involves analyses of the evolution patterns of blasting stress,characteristics of crack distribution,and rock fracture features in the ***,blasting model experiments were carried out using the dynamic caustics principle to investigate the influence of bottom cushion layers and initiation methods on the integrity of the bottom rock *** experimental results indicate that the combined use of bottom cushion layers and inverse initiation effectively protects the integrity of the bottom rock ***,the process of stress wave propagation and dynamic crack propagation in rocks was simulated using the continuum-discontinuum element method(CDEM)and the Landau explosion source model,with varying thicknesses of bottom cushion *** numerical simulation results indicate that with increasing cushion thickness,the absorption of energy generated by the explosion becomes more pronounced,resulting in fewer cracks in the bottom rock *** illustrates the positive role of the cushion layer in protecting the integrity of the bottom rock mass.

关键词： bottom cushion layer blasting crack propagation continuum-discontinuum element method dynamic stress intensity factor

Software-defined process-near-memory architecture using 3D hybrid bonding integration

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Science China(Information Sciences) 2025年第1期68卷 366-378页

作者： Anlin xu Chenchen DENG Jianfeng zhu Yao WANG Shaojun WEI Leibo LIU School of Integrated Circuits Tsinghua University Beijing Institution of Tracking and Communication Technology Beijing National Research Center for Information Science and Technology Tsinghua University

With the unprecedented explosive growing amount of global data, the development of computing chips, which encounter bottlenecks such as power wall and memory wall, cannot satisfy the demanding requirement. This work proposes a software-defined process-near-memory(SDPNM) computing architecture implemented using 3D hybrid bonding *** software-defined chip architecture, featuring spatial computations and dynamic reconfiguration, innovates in a top-down manner to achieve high energy efficiency while maintaining flexibility after fabrication. The process-near-memory integration further advances the SDNPM chip in a bottom-up way to reduce the energy consumption of data movement while improving the bandwidth. Utilizing a relatively mature fabrication and bonding process can result in feasible solutions for both data-intensive and compute-intensive applications including digital signal processing and artificial intelligence. The logic die is fabricated in the SMIC 40 nm process and the DRAM die is fabricated in the PSMC 25 nm process. The hybrid bonding is implemented by XMC. The experimental results show that the energy efficiency of the proposed SDPNM chip is 33.1× better than the state-of-the-art FPGA ranging from 8.2× to 104.1×.

关键词： software-defined chips process near memory energy efficiency dynamic reconfiguration domain specific

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