检索结果-南通市图书馆

A medical robot for needle placement therapy in liver cancer

在线全文

学校读者我要写书评

暂无评论

Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第4期11卷 263-269页

作者： Xing-guang duan Gui-bin BIAN Hong-hua ZHAO Xing-tao WANG Qiang HUANG Intelligent Robotics Institute Beijing Institute of Technology Beijing 100081 China

Hepatocellular carcinoma (HCC) is the second most common malignancy in *** microwave ablation (MWA) is an effective method for liver cancer,a robotic surgical system with ultrasound-directed was designed to assist surgeons on positioning the *** robotic system includes a surgical robot with 5 degrees of freedom,a workstation for path-planning and image processing,a conventional 2D ultrasound device,and an electromagnetic (EM) tracking *** space,clinical operation requirements and optimal mechanical structure are the key factors to be considered in designing a medical robot suitable for use by *** on the mechanics of the needle placement robot,we have conducted detailed kinematic analysis,including a combined numerical algorithm and coordinate ***,the feasibility of the needle placement robot has been validated by experiment.

关键词： Surgical robot Needle insertion Inverse kinematics Numerical solution

Controlled Radical Photopolymerization of n-Butyl Methacrylate in Bluk Mediated by HTEMPO

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2006年第8期17卷 1109-1112页

作者： Xiao Xuan LIU Mei HAN Lun Yong duan guang Guo WU Department of Chemistry College of Science Shantou University Shantou 515063

Controlled radical photopolymerization of n-butyl methacrylate（n-BMA） mediated by 4-hydroxy-2,2,6,6-tetramethyl-1-piperidinyloxy（HTEMPO） was carried out in bulk at ambient temperature. It was found that obtained n-BMA homopolymers exhibited narrow polydispersities of around 1.4, which was characterized by GPC. Plots of number-average molecular weight vs. conversion and Ln（[Mo]/[M]） vs. time were liner respectively, indicating that was a controlled photopolymerization.

关键词： photopolymerization nitroxide n-butyl methacrylate HTEMPO.

A Simple Synthesis of dl-Shikonin

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2002年第2期13卷 113-114页

作者： Qun LU Wen Hu duan Jun Chao cai Shanghai Institute of Materia Medica SIBSChinese Academy of SciencesShanghai 200031

A new facile route for the synthesis of dl-shikonin is presented. Reformatsky reaction assisted cross-coupling of 1, 4, 5, 8-tetramethoxynaphthalene-2-carbaldehyde and ethyl- bromoacetate was employed for introductio... 详细信息

关键词： Synthesis dl-shikonin Reformatsky reaction.

A Distributed LRTCO Algorithm in Large-Scale DVE Multimedia Systems

在线全文

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2018年第7期56卷 73-89页

作者： Hangjun Zhou guang Sun Sha Fu Wangdong Jiang Tingting Xie Danqing duan Hunan University of Finance and Economy Fenglin RoadNo.139Changsha410205China Nanjing University of Science and Technology Xiaolingwei RoadNo.200Nanjing210094China School of Electrical Engineering and Computer Science Queen Mary University of LondonMile End RdLondon E14NSUK

In the large-scale Distributed Virtual Environment(DVE)multimedia systems,one of key challenges is to distributedly preserve causal order delivery of messages in real *** of the existing causal order control approaches with real-time constraints use vector time as causal control information which is closely coupled with system *** the scale expands,each message is attached a large amount of control information that introduces too much network transmission overhead to maintain the real-time causal order *** this article,a novel Lightweight Real-Time Causal Order(LRTCO)algorithm is proposed for large-scale DVE multimedia *** predicts and compares the network transmission times of messages so as to select the proper causal control information of which the amount is dynamically adapted to the network latency variations and unconcerned with system *** control information in LRTCO is effective to preserve causal order delivery of messages and lightweight to maintain the real-time property of DVE *** results demonstrate that LRTCO costs low transmission overhead and communication bandwidth,reduces causal order violations efficiently,and improves the scalability of DVE systems.

关键词： Distributed computing distributed virtual environment multimedia system causality violation causal order delivery real time

Modulation of the octahedral structure and potential superconductivity of La3Ni2O7 through strain engineering

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

Science China(Physics,Mechanics & Astronomy) 2025年

作者： Zihao Huo Zhihui Luo Peng Zhang Aiqin Yang Zhengtao Liu Xiangru Tao Zihan Zhang Shumin Guo Qiwen Jiang Wenxuan Chen Dao-Xin Yao Defang duan Tian Cui Key Laboratory of Material Simulation Methods & Software of Ministry of Education State Key Laboratory of Superhard Materials College of Physics Jilin University Center for Neutron Science and Technology Guangdong Provincial Key Laboratory of Magnetoelectric Physics and Devices State Key Laboratory of Optoelectronic Materials and Technologies School of Physics Sun Yat-sen University MOE Key Laboratory for Non-equilibrium Synthesis and Modulation of Condensed Matter Shaanxi Province Key Laboratory of Advanced Functional Materials and Mesoscopic Physics School of Physics Xi'an Jiaotong University Institute of High Pressure Physics School of Physical Science and Technology Ningbo University

The recent transport measurements of La3Ni2O7uncovered a“right-triangle”shape of the superconducting dome in the pressure-temperature （P-T） phase *** by this,we perform theoretical first-principles studies of La3Ni2O7with the pressure ranging from 0 to 100 ***,we reveal a pressure dependence of the Ni-d2zelectron density at the Fermi energy (nE Fz) that highly coincides with such *** this basis,we further explore the electronic structure under uniaxial *** tracking the stress response of nE Fz,we propose that superconductivity can be achieved by applying only～2 GPa of compression along the c *** idea is further exemplified from the perspectives of lattice distortion,band structure,Fermi surface and superconducting phase *** also discuss the possible charge modulation under the stress and provide an insight into the relation between nE Fzand the superconducting Tcin *** study provides new routes to the search of high-Tcsuperconductors in future experiments.

关键词：

Reaction Mechanism,Synthesis and Characterization of Urea-glyoxal(UG) Resin

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Structural Chemistry 2013年第12期32卷 1773-1786页

作者： DENG Shu-duan LI Xiang-Hong XIE Xiao-guang DU Guan-Ben College of Materials Science and Technology Beijing Forestry University Yunnan Key Laboratory of Wood Adhesives and Glue Products Southwest Forestry University School of Chemical Science and Technology Yunnan University

The reaction mechanism of glyoxal （G） with urea （U） under weak acid condition was theoretically investigated at PW91/DNP/COSMO of quantum chemistry using density functional theory （DFT） method. The results show that the addition reaction of G with U under the conditions mainly involves the reactions of U with protonated glyoxal （p-G）, protonated 2,2-dihy- droxyacetaldehyde （p-G 1） and protonated bis-hemdiol （p-G2） to form two important carbocation reactive intermediates of C-p-UG and C-p-UG1, and two important hydroxyl compounds of UG and UG1. These compounds play important roles in the formation of UG resin. According to the result of quantum chemical calculation, UG resin was synthesized successfully under weak acid conditions. The UG resin was characterized by matrix assisted laser desorption ionization time of flight mass spectrometry （MALDI-TOF-MS）, ultraviolet and visible spectroscopy （UV-vis）, Fourier transform infrared spectroscopy （FT1R） and nuclear magnetic resonance spectroscopy （13CNMR and 1HNMR）. These instrumental analytical results agree with each other and further confirm the addition reaction pathway of glyoxal with urea proposed by quantum chemical calculation.

关键词： urea-glyoxal (UG) resin reaction mechanism,synthesis MALDI-TOF FTIR NMR UV-vis

Water modeling on fluid flow and mixing phenomena in a BOF steelmaking converter

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3期31卷 595-607页

作者： Xin-yu cai Hao-jian duan Ding-han Li Anjun Xu Li-feng Zhang School of Metallurgical and Ecological Engineering University of Science and Technology Beijing(USTB)Beijing 100083China School of Mechanical and Materials Engineering North China University of TechnologyBeijing 100144China

A 1∶8 physical water model was constructed to investigate the fluid flow and mixing phenomena in the basic oxygen furnace(BOF)*** particle image velocimetry was employed to measure the velocity distribution of the bath and the high-speed camera was applied to capture the cavity shape in the combined blowing BOF *** mixing time for varied operating conditions was measured by the stimulus-response *** cavity depth increased with the decrease in the lance height and the increase in the top gas flow rate while the bottom blowing gas had little influence on the cavity *** minimum cavity depth was obtained under the condition of a 69.8 m^(3)/h top gas flow rate,a 287.5 mm lance height and a 0.93 m^(3)/h bottom blowing gas flow rate,which was 161.2 *** mixing time decreased as the lance height decreased and the top blowing gas flow rate *** mixing time was first decreased and then increased with the increase in the bottom gas flow *** the condition of 69.8 m^(3)/h gas flow rate of top blowing,the 287.5 mm lance height and the 0.93 m^(3)/h gas flow rate of bottom blowing,the mixing time in the converter was 48.65 *** empirical formula between the stirring power and the mixing time in the converter was calculated.

关键词： Water model Fluid flow Particle image velocimetry Mixing time BOF converter

Quantifying freeze-melt dynamics of lakes on the Tibetan Plateau using Sentinel-1 synthetic aperture radar imagery

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

Journal of Mountain Science 2024年第3期21卷 805-819页

作者： JIN Lu CHEN Jun cai Yu KONG Yecheng WANG Yongfeng duan Zheng School of Environment and Energy Engineering Anhui Jianzhu UniversityHefei 230601China Anhui Engineering and Technology Research Center for Smart City Anhui Jianzhu UniversityHefei 230601China School of Geographic and Oceanographic Sciences Nanjing UniversityNanjing 210023China Department of Physical Geography and Ecosystem Science Lund UniversityLund 22362Sweden

The ice phenology of alpine lakes on the Tibetan Plateau(TP)is a rapid and direct responder to climate changes,and the variations in lake ice exhibit high temporal frequency *** and passive microwave data are widely used to monitor lake ice changes with high temporal ***,the low spatial resolutions make it difficult to effectively quantify the freeze-melt dynamics of *** work used Sentinel-1 synthetic aperture radar(SAR)data to derive high-resolution ice maps(about 6 days),then with the aid of Sentinel-2 optical images to quantify freeze-melt processes in three typical lakes on the TP(*** Co,Ayakekumu Lake,and Nam Co).The results showed that three lakes had an average annual ice period of 125-157 days and a complete ice cover period of 72-115 days,from 2018 to *** exhibit different ice phenology *** Co is characterized by repeated episodes of freezing,melting,and refreezing,resulting in a prolonged freeze-up ***,the break-up period of Nam Co lasts for a longer duration(about 19 days),and the break-up exhibits a smooth ***,Ayakekumu Lake showed more significant inter-annual fluctuations in the freeze-up period,with deviations of up to 28 days observed among different *** to the other two lakes,Selin Co experienced a relatively short freeze-up and break-up *** short,Sentinel-1 SAR data can effectively monitor the weekly and seasonal variations in lake ice on the ***,this data facilitates quantification of the freeze-melt dynamics.

关键词： Lake ice Sentinel-1 SAR Tibetan Plateau Climate change

Transcriptome and metabolomics analysis revealed that CmWRKY49 regulating CmPSY1 promotes β-carotene accumulation in orange fleshed oriental melon

在线全文

学校读者我要写书评

暂无评论

Horticultural Plant Journal 2022年第5期8卷 650-666页

作者： Xiaoyu duan cai Jiang Yaping Zhao Ge Gao Meng Li Hongyan Qi Key Laboratory of Protected Horticulture of Education Ministry and Liaoning Province College of HorticultureShenyang Agricultural UniversityNational and Local Joint Engineering Research Centre of Northern HorticulturalFacilities Design and Application Technology(Liaoning)Shenyang 110866China Nanodigmbio Biotechnology Co. Ltd.Nanjing 210038China

The flesh color of oriental melons is an important commercial trait that affects consumer *** explore the mechanisms underlying the flesh color formation and regulation during fruit ripening,carotenoid-targeted metabolomic and RNA-seq analysis were conducted between white-fleshed(WF) and orange-fleshed(OF) oriental melon cultivars at different *** carotenoid-targeted metabolomic analysis indicated that β-carotene was the major metabolite that caused differences in flesh color between the two ***,through KEGG pathway enrichment and weighted gene co-expression network(WGCNA) analysis,metabolic pathways and related transcription factors that are associated with carotenoid metabolism were selected and transcriptome data was verified using ***,the yeast one hybrid and luciferase activity showed that the transcription factor CmWRKY49 could directly bind to the CmPSY1 promoter to activate its expression in the ’OF’ *** overexpression of CmWRKY49 in ’OF’ cultivar increased the β-carotene content,while the β-carotene content decreased when it was silenced in the same *** study provides insights into the underlying regulatory network of carotenoid metabolism in oriental melon fruit.

关键词： Oriental melon Carotenoid Transcriptome analysis WRKY CmPSY1