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液环泵喷射器内流场及其与液环泵匹配特性

华中科技大学学报（自然科学版） 2021年第4期49卷 8-13页

作者：蒋利杰张人会陈学炳兰州理工大学能源与动力工程学院甘肃兰州730050 兰州理工大学甘肃省流体机械及系统重点实验室甘肃兰州730050

为研究喷射器内流场特性及其与液环泵的匹配关系,在液环泵进口前串联喷射器,通过数值模拟和试验相结合的方法对液环泵喷射器系统内流动进行研究,分析喷射器内部超声速射流产生的激波现象及其与边界层相互干扰引起的流动分离复杂流动结构... 详细信息

为研究喷射器内流场特性及其与液环泵的匹配关系,在液环泵进口前串联喷射器,通过数值模拟和试验相结合的方法对液环泵喷射器系统内流动进行研究,分析喷射器内部超声速射流产生的激波现象及其与边界层相互干扰引起的流动分离复杂流动结构,研究不同尺寸喷射器和液环泵的匹配关系及其对泵性能的影响机理.结果表明:喷嘴出口在压差作用下产生超声速射流,形成规则分布的激波串,激波与边界层相互干扰引起了流动分离,压力、密度和马赫数等参数在喷嘴出口呈振荡分布;液环泵进口前串联大气喷射器,在合理的匹配条件下能提升系统吸入口的真空度及流量,改善液环泵进口的工作条件;一定范围内随着喷射器几何尺寸的增大,引射真空度逐渐增大、泵进口吸气量逐渐提升,喷射器有效工作范围增大.

关键词：液环泵喷射器激波现象流动分离匹配特性真空度

Enhancement of CH_(3)CO^(*) adsorption by editing d-orbital states of Pd to boost C–C bond cleavage of ethanol eletrooxidation

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Science China Chemistry 2024年第2期67卷 696-704页

作者： Yuchen Qin Fengqi Wang Pei Liu Jinyu Ye Qian Wang Yao Wang Guangce jiang lijie Liu Pengfang Zhang Xiaobiao Liu Xin Zheng Yunlai Ren Junjun Li Zhicheng Zhang College of Sciences Henan Agricultural UniversityZhengzhou450000China Tianjin Key Laboratory of Molecular Optoelectronic Sciences Department of ChemistrySchool of ScienceTianjin University&Collaborative Innovation Center of Chemical Science and EngineeringTianjin300072China College of Chemistry and Chemical Engineering Xiamen UniversityXiamen361005China Department of Analysis Sinopec Engineering Group Luoyang R&D Center of TechnologyLuoyang471000China School of Chemical and Material Engineering Jiangnan UniversityWuxi214211China Shandong Provincial Key Laboratory of Chemical Energy Storage and Novel Cell Technology Liaocheng UniversityLiaocheng252000China

Improving the complete ethanol electrooxidation on Pd-based catalysts in alkaline media has drawn widely attention due to the high mass energy ***,the weak adsorption energy of CH_(3)CO^(*) on Pd restricts the C–C bond *** by the molecular orbital theory,we proposed the d-state-editing strategy to construct more unoccupied d-states of Pd for the enhanced interaction with CH_(3)CO^(*) to break C–C *** expected,the reduced number of e_g electrons and more unoccupied d-states of Pd successfully formed on as-prepared porous Rh Au–Pd Cu nanosheets(PNSs).Theoretical calculations show that the optimized d-states of Rh Au–Pd Cu PNS can effectively improve the adsorption of CH_(3)CO^(*) and drastically reduce the energy barrier of C–C bond cleavage,thus boosting the complete oxidation of *** charge ratio of C_1 pathway on Rh Au–Pd Cu PNSs is 51.5%,more than 2 times higher than that of Pd *** finding provides an innovative perspective for the design of highly-efficient noble-based electrocatalysts.

关键词： C–C bond cleavage CH_(3)CO^(*)adsorption unoccupied d-states ethanol oxidation reaction RhAu–PdCu porous nanosheets

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一种同/异步四肢联动康复机器人的研究

仪器仪表学报 2017年第10期38卷 2381-2390页

作者：姜礼杰张方双任刚跃王勇合肥工业大学机械工程学院合肥230009

为提高偏瘫患者健、患侧肢体协调运动能力,研制了一种新型坐式单驱动四肢联动康复机器人,它能够在主被动模式下为偏瘫患者的肢体提供同异步协同训练。基于平面七连杆变胞机构设计了一种可实现四肢协调运动的训练机构,通过传动系统调节... 详细信息

为提高偏瘫患者健、患侧肢体协调运动能力,研制了一种新型坐式单驱动四肢联动康复机器人,它能够在主被动模式下为偏瘫患者的肢体提供同异步协同训练。基于平面七连杆变胞机构设计了一种可实现四肢协调运动的训练机构,通过传动系统调节两侧训练机构曲柄的相位差,实现左右两侧肢体同步或异步联合运动;在矢状面内建立人-机模型及训练机构进行运动学分析,从理论上证明该机构能够实现四肢联动的可行性;基于智能移动终端和微控制器开发了上下位机控制系统,并在样机上进行了试验,结果表明试验者在机器人作用下能够实现:肩关节-16.9°~15.1°、膝关节121.5°~172.5°的上下肢协同运动;0~6 r/min速度范围的同/异步被动训练和61.82~227 N足底压力范围的异步主动训练;同/异步训练模式之间可自动切换。

关键词：康复机器人偏瘫患者四肢联动同/异步训练机构设计与分析

Epidemic Characteristics and Spatio-Temporal Patterns of HFRS in Qingdao City,China,2010-2022

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Biomedical and Environmental Sciences 2024年第9期37卷 1015-1029页

作者： Ying Li Runze Lu Liyan Dong Litao Sun Zongyi Zhang Yating Zhao Qing Duan lijie Zhang Fachun jiang Jing Jia Huilai Ma Chinese Field Epidemiology Training Program Chinese Center for Disease Control and PreventionBeijing 100050China National Institute for Viral Disease Control and Prevention Chinese Center for Disease Control and PreventionBeijing 102206China Qingdao Municipal Center for Disease Control and Prevention Qingdao 266024ShandongChina Jiaozhou Center for Disease Control and Prevention Qingdao 266399ShandongChina Institute for Infectious Disease Control and Prevention Shandong Center for Disease Control and PreventionJinan 250013ShandongChina Office of Epidemiology(Technical Guidance Office for Patriotic Health Work) Chinese Center for Disease Control and PreventionBeijing 102206China

Objective This study investigated the epidemic characteristics and spatio-temporal dynamics of hemorrhagic fever with renal syndrome(HFRS)in Qingdao City,*** Information was collected on HFRS cases in Qingdao City from 2010 to *** epidemiologic,seasonal decomposition,spatial autocorrelation,and spatio-temporal cluster analyses were *** A total of 2,220 patients with HFRS were reported over the study period,with an average annual incidence of 1.89/100,000 and a case fatality rate of 2.52%.The male:female ratio was 2.8:1.75.3%of patients were aged between 16 and 60 years old,75.3%of patients were farmers,and 11.6%had both“three red”and“three pain”*** HFRS epidemic showed two-peak seasonality:the primary fall-winter peak and the minor spring *** HFRS epidemic presented highly spatially heterogeneous,street/township-level hot spots that were mostly distributed in Huangdao,Pingdu,and *** spatio-temporal cluster analysis revealed three cluster areas in Qingdao City that were located in the south of Huangdao District during the fall-winter *** The distribution of HFRS in Qingdao exhibited periodic,seasonal,and regional characteristics,with high spatial clustering *** typical symptoms of“three red”and“three pain”in patients with HFRS were not obvious.

关键词： Hemorrhagic fever with renal syndrome Epidemic characteristics Spatio-temporal distribution

A novel nondestructive detection approach for seed cotton lint percentage using deep learning

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Journal of Cotton Research 2024年第2期7卷 148-162页

作者： GENG lijie YAN Pengji JI Zhikun SONG Chunyu SONG Shuaifei ZHANG Ruiliang ZHANG Zhifeng ZHAI Yusheng jiang Liying YANG Kun School of Electronic and Information Henan Key Laboratory of Magnetoelectronic Information Functional MaterialsZhengzhou University of Light IndustryZhengzhou 450002HenanChina

Background The lint percentage of seed cotton is one of the most important parameters for evaluating seed cotton quality and affects its *** traditional measuring method of lint percentage is labor-intensive and time-consuming;thus,an efficient and accurate measurement method is *** recent years,classification-based deep learning and computer vision have shown promise in solving various classification *** In this study,we propose a new approach for detecting the lint percentage using MobileNetV2 and transfer *** model is deployed on a lint percentage detection instrument,which can rapidly and accurately determine the lint percentage of seed *** evaluated the performance of the proposed approach using a dataset comprising 66924 seed cotton images from different regions of *** results of the experiments showed that the model with transfer learning achieved an average classification accuracy of 98.43%,with an average precision of 94.97%,an average recall of 95.26%,and an average F1-score of 95.20%.Furthermore,the proposed classification model achieved an average accuracy of 97.22%in calculating the lint percentage,showing no significant difference from the performance of experts(independent-sample t-test,t=0.019,P=0.860).Conclusion This study demonstrated the effectiveness of the MobileNetV2 model and transfer learning in calculating the lint percentage of seed *** proposed approach is a promising alternative to traditional methods,providing a rapid and accurate solution for the industry.

关键词： Neural network MobileNetV2 Nondestructive detection Smart agriculture Seed cotton lint percentage

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一种新型下肢康复机器人的机构设计与分析

华中科技大学学报（自然科学版） 2018年第12期46卷 13-17页

作者：王勇梁启松姜礼杰任刚跃合肥工业大学机械工程学院安徽合肥230009 中铁工程装备集团有限公司河南郑州450016

针对缺少在社区与家庭中使用的康复机器人的现状,提出一种新型下肢康复机器人设计方案.首先,根据患者康复训练需求完成了机器人的机构设计,建立了机器人的三维模型并介绍了其具体结构;其次,在矢状面内建立人-机模型并对机构进行运动学分... 详细信息

针对缺少在社区与家庭中使用的康复机器人的现状,提出一种新型下肢康复机器人设计方案.首先,根据患者康复训练需求完成了机器人的机构设计,建立了机器人的三维模型并介绍了其具体结构;其次,在矢状面内建立人-机模型并对机构进行运动学分析,对精确实现踝关节规划轨迹的控制规律进行了仿真分析;最后,基于样机进行了多位姿试验.试验结果表明:机器人能够实现"坐-卧-站"多位姿康复训练,该机器人设计方案具有可行性,能够为不同康复期的下肢偏瘫患者提供针对性的康复训练轨迹,有助于偏瘫患者康复训练.

关键词：下肢康复机器人偏瘫患者机构设计机构分析仿真分析与试验

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改进型相位相关法在药液图像配准中的应用

光电工程 2014年第9期41卷 69-74页

作者：姜利杰白瑞林李新江南大学轻工过程先进控制教育部重点实验室江苏无锡214122 无锡信捷电气股份有限公司江苏无锡214072

针对瓶装药液微小异物视觉检测系统中,由于平台和相机振动所导致的序列图像中瓶体出现不同程度的随机偏移问题,提出了一种基于改进型相位相关法的药液图像配准方法。首先,引入图像投影将原始相位相关配准算法分解为两个一维配准算法,显... 详细信息

针对瓶装药液微小异物视觉检测系统中,由于平台和相机振动所导致的序列图像中瓶体出现不同程度的随机偏移问题,提出了一种基于改进型相位相关法的药液图像配准方法。首先,引入图像投影将原始相位相关配准算法分解为两个一维配准算法,显著提高算法实时性。其次,引入Hanning窗函数滤波,克服图像边缘"不连续性"对配准精度的影响。最后,针对原始相位相关配准算法只能达到像素级配准精度的缺点,引入峰值估计技术,将配准精度提高到亚像素级。实验结果表明,本文方法配准精度可达1/100像素级,并对于亮度变化、噪声干扰具有一定免疫性,能满足瓶装药液微小异物视觉检测系统的实际生产要求。

关键词：相位相关图像配准异物检测机器视觉

税法总则目标下税收效率原则的功能定位与制度保障

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税务研究 2023年第8期 67-75页

作者：刘剑文江利杰辽宁大学法学院

凝聚改革共识、实现税法体系融贯、指引税法规则完善,是税法总则制定的基础。既往学术界对税收效率原则疏于关照,相关论述多借鉴自税收学成果,未在税法领域进行充分的体系构建,难以权衡实践中税收效率原则与税收法定原则、税收公平原则... 详细信息

凝聚改革共识、实现税法体系融贯、指引税法规则完善,是税法总则制定的基础。既往学术界对税收效率原则疏于关照,相关论述多借鉴自税收学成果,未在税法领域进行充分的体系构建,难以权衡实践中税收效率原则与税收法定原则、税收公平原则间的冲突。税收效率原则以“弃实就虚”为特征,是资源有限背景下实现民主目标的漏洞填补方式,即:对税收法定进行“目的性扩张”,导向一种相对法定主义;对税收公平进行“目的性限缩”,体现为相对公平的要求。在建制逻辑上,既要遵循比例原则的理论检验,也要经由立法程序的共识凝聚与个案平衡的制度保障,实现税收效率原则与税收法定原则、税收公平原则的统一。

关键词：税法总则税收效率原则技术正义比例原则税收法定原则

Cryo-EM structure of cannabinoid receptor CB1-β-arrestincomplex

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Protein & Cell 2024年第3期15卷 230-234页

作者： Yuxia Wang lijie Wu Tian Wang Junlin Liu Fei Li Longquan jiang Zhongbo Fan Yanan Yu Na Chen Qianqian Sun Qiwen Tan Tian Hua Zhi-Jie Liu iHuman Institute ShanghaiTech UniversityShanghai 201210China School of Life Science and Technology ShanghaiTech UniversityShanghai 201210China Institute of Molecular and Clinical Medicine Kunming Medical UniversityKunming 650500China

Dear Editor,G protein-coupled receptors(GPCRs)play a vital role in regulating almost every aspect of human physiology,making up more than one-third of marketed drug targets(Santos et al.,2017).GPCRs orchestrate their signalling through interactions with three distinct downstream protein families:G proteins,G protein-coupled receptor kinases(GRKs),and arrestins(Santos et al.,2017).While G protein-mediated signalling is initiated upon GPCR stimulation,activated GPCRs return to their basal levels through a GRK-and arrestin-regulated desensitization process(Santos et al.,2017).In addition to modulating receptor desensitization,β-arrestin also regulates downstream events that are distinct from classical G protein signalling(Ahn et al.,2020).

关键词： stimulation return