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Three-Dimensional Reconstruction of Welding Pool Surface by Binocular Vision

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Chinese Journal of Mechanical Engineering 2021年第3期34卷 272-284页

作者： Zunan Gu ji Chen Chuansong wu Key Laboratory for Liquid-Solid Structural Evolution&Processing of Materials Ministry of EducationInstitute of Materials JoiningShandong UniversityJinan 250061China

Current research of binocular vision systems mainly need to resolve the camera’s intrinsic parameters before the reconstruction of three-dimensional(3D)*** classical Zhang’calibration is hardly to calculate all errors caused by perspective distortion and lens ***,the image-matching algorithm of the binocular vision system still needs to be improved to accelerate the reconstruction speed of welding pool *** this paper,a preset coordinate system was utilized for camera calibration instead of Zhang’*** binocular vision system was modified to capture images of welding pool surfaces by suppressing the strong arc interference during gas metal arc *** and improving the algorithms of speeded up robust features,binary robust invariant scalable keypoints,and KAZE,the feature information of points(i.e.,RGB values,pixel coordinates)was extracted as the feature vector of the welding pool *** on the characteristics of the welding images,a mismatch-elimination algorithm was developed to increase the accuracy of image-matching *** world coordinates of matching feature points were calculated to reconstruct the 3D shape of the welding pool *** effectiveness and accuracy of the reconstruction of welding pool surfaces were verified by experimental *** research proposes the development of binocular vision algorithms that can reconstruct the surface of welding pools accurately to realize intelligent welding control systems in the future.

关键词： Surface reconstruction Welding pool Binocular imaging Gas metal arc welding Feature points matching

Effect of charge on the stability of single-walled carbon nanotubes

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Science China(Physics,Mechanics & Astronomy) 2004年第6期47卷 685-693页

作者： LUO ji wu jinlei Department of Electronics Peking University Beijing 100871 China Department of Electronics Peking University Beijing 100871 China

By using density-functional-theory based DMol3 code, the structure optimizations are performed on a short charged single-walled carbon nanotube. Results show that the total energy of the nanotube exhibits a parabolic variation with respect to the amount of extra charge, and one negatively charged nanotube has the lowest total energy; thus the carbon nanotube has a positive electron affinity. When the charge is small, the variation of the atomic structure of the nanotube is also small, and neglecting the atomic structure variation leads to the qualitatively correct properties of the total energy and the energy of the highest occupied molecular orbital. When the extra charge is large, the end structure of the nanotube will be first affected and form into a trumpet shape. With the increasing of the extra charge, the nanotube end gradually becomes unstable, and this may lead to the ultimate destruction of the nanotube.

关键词： carbon nanotube, density-functional theory, charge, stability.

脑血管病急性期血尿酸/血肌酐比值与脑血管事件复发及死亡的关系:一项前瞻性队列研究

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中国全科医学 2025年第2期28卷 175-182,192页

作者：任小乔王盼吴昊纪勇石志鸿天津医科大学神经内外科及神经康复临床学院天津市300070 天津市环湖医院 300350

背景脑卒中在世界各地有较高的死亡率和复发率。血尿酸(SUA)是嘌呤代谢的产物,已被认为是心脑血管病的危险因素。血尿酸/血肌酐比值(SUA/Scr)是代表肾功能标准化的SUA,目前有关SUA/Scr在急性脑血管病中的作用仍有争议。目的探讨脑血管... 详细信息

背景脑卒中在世界各地有较高的死亡率和复发率。血尿酸(SUA)是嘌呤代谢的产物,已被认为是心脑血管病的危险因素。血尿酸/血肌酐比值(SUA/Scr)是代表肾功能标准化的SUA,目前有关SUA/Scr在急性脑血管病中的作用仍有争议。目的探讨脑血管病急性期SUA/Scr与脑血管事件复发和死亡的关系。方法本研究为前瞻性队列研究,选取2006年9月—2019年9月天津市环湖医院连续收治的首次发生脑血管事件的13313例患者为研究队列,并对患者进行随访,随访截至2020年9月。随访方式为门诊及电话相结合。随访主要终点事件为全因死亡,次要终点事件为脑血管事件复发、心血管事件复发、其他血管事件发生(如下肢动静脉栓塞)。采用Cox比例风险回归模型探究SUA/Scr与脑血管事件复发与死亡的关系。结果根据脑血管病急性期SUA/Scr四分位数,将患者分为Q1组(SUA/Scr≤3.16,n=3520)、Q2组(3.164.92,n=3243)。截至随访结束,774例(5.8%)患者死亡,2064例(15.5%)患者复发脑血管事件。脑血管病急性期SUA/Scr位于Q1~Q4的患者中,男性复发脑血管病的例数依次为302、375、408、337例,女性依次为99、125、169、249例;男性复发脑梗死的例数依次为261、314、345、283例,女性依次为90、101、142、205例;男性复发大动脉粥样硬化型脑梗死的例数依次为154、191、214、183例,女性依次为58、52、45、31例;男性全因死亡的例数依次为165、128、131、88例,女性依次为57、63、62、80例;男性因脑梗死死亡的例数依次为93、72、70、46例,女性依次为31、33、36、44例;男性因大动脉粥样硬化型脑梗死死亡的例数依次为58、52、45、31例,女性依次为17、18、27、24例。调整多项混杂因素后,SUA/Scr位于Q4相较于Q1是男性急性脑梗死复发的影响因素(HR=0.690,95%CI=0.500~0.953,P=0.026);SUA/Scr位于Q4相较于Q1是男性脑梗死亚组患者大动脉粥样硬化型脑梗死复发的影响因素(HR=0.740,95%CI=0.578~0.947,P=0.017)。SUA/Scr位于Q4相较于Q1是男性全因死亡、因脑梗死死亡的影响因素(HR=0.575,95%CI=0.368~0.901,P=0.003;HR=0.610,95%CI=0.353~0.814,P=0.011)。SUA/Scr位于Q3、Q4相较于Q1是男性出院后死亡的影响因素(HR=0.656,95%CI=0.476~0.904,P=0.010;HR=0.582,95%CI=0.409~0.829,P=0.001)。SUA/Scr位于Q4相较于Q1是男性脑梗死亚组患者因大动脉粥样硬化型脑梗死死亡的影响因素(HR=0.580,95%CI=0.386~0.873,P=0.007)。结论一定范围内,脑血管病急性期SUA/Scr升高对男性患者脑血管事件复发及死亡有一定的保护作用,低SUA/Scr与男性大动脉粥样硬化型脑梗死的死亡和复发风险升高有关,但与小动脉闭塞型脑梗死和心源性卒中复发和死亡无关。在女性患者中没有观察到SUA/Scr与脑血管事件复发及死亡的关系。

关键词：脑血管障碍脑卒中血尿酸/血肌酐比值动脉粥样硬化男性复发死亡队列研究前瞻性研究 Cox比例风险回归模型

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Intermodal interference based refractive index sensor employing elliptical core photonic crystal fiber

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Optoelectronics Letters 2021年第5期17卷 271-275页

作者： wu Xu-jie song Bin-bin wu ji-xuan HUANG Wei The Key Laboratory of Computer Vision and System of Ministry of Education Tianjin Key Laboratory of Intelligence Computing and Novel Software TechnologyTianjin University of TechnologyTianjin 300384China Tianjin Key Laboratory of Optoelectronic Detection Technology and Systems College of Electronic and Information EngineeringTiangong UniversityTianjin 300387China

A refractive index(RI)sensor based on elliptical core photonic crystal fiber(EC-PCF)has been *** asymmetric elliptical core introduces the polarization-dependent characteristics of the fiber core *** performances of intermodal interference between the intrinsic polarization fiber core modes are investigated by contrast in two interferometers based on the Mach-Zehnder(M-Z)and Sagnac interference *** addition,the RI sensing characteristics of the two interferometers are studied by successively filling the three layers air holes closest to the elliptical core in the *** results show that the M-Z interference between LP_(01)and LP_(11)mode in the same polarized direction is featured with the incremental RI sensing sensitivity as the decreasing interference length,and the infilled scope around the elliptical core has a weak correlation with the RI sensing *** to the high birefringence of LP11 mode,the Sagnac interferometer has better RI sensing performance,the maximum RI sensing sensitivity of 12000 nm/RIU is achieved under the innermost one layer air holes infilled with RI matching liquid of RI=1.39 at the pre-setting EC-PCF length of 12 cm,which is two orders of magnitude higher than the M-Z interferometer with the same fiber *** series of theoretical optimized analysis would provide guidance for the applications in the field of biochemical sensing.

关键词： Sagnac PCF Intermodal interference based refractive index sensor employing elliptical core photonic crystal fiber

Study of the synthesis,antiviral bioactivity and interaction mechanisms of novel chalcone derivatives that contain the 1,1-dichloropropene moiety

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Chinese Chemical Letters 2017年第7期28卷 1566-1570页

作者： Liang-Run Dong De-Yu Hu Zeng-Xue wu ji-Xiang Chen Bao-An song State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering Key Laboratory of Green Pesticide and Agricultural BioengineeringMinistry of EducationResearch and Development Center for Fine ChemicalsGuizhou UniversityGuiyang 550025China

A series of novel chalcone derivatives that contain the 1,1-dichloropropene moiety was designed and synthesized. Bioactivity assays showed that most of the target compounds exhibited moderate to good antiviral activity against tobacco mosaic virus（TMV） at 500 mg/m L. Among the target compounds,compound 7h showed the highest in vivo inactivation activity against TMV with the EC50 and EC90value of 45.6 and 327.5 mg/m L, respectively, which was similar to that of Ningnanmycin（46.9 and 329.4 mg/m L）and superior to that of Ribavirin（145.1 and 793.1 mg/m L）. Meanwhile, the microscale thermophoresis and fluorescence spectroscopy experiments showed that the compound 7h had a strong interaction with the tobacco mosaic virus coat protein.

关键词： Chalcone derivatives 1 1-Dichloropropene moiety Synthesis Antiviral activity Interaction mechanisms

Effect of structural characteristics on the transport characteristics of solid particles in the thermal storage and release system of circulating fluidized bed

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Particuology 2024年第6期89卷 22-31页

作者： Zengcai ji Guoliang song Zihua Tang Liwei Sun Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing100190China University of Chinese Academy of Sciences Beijing100049China Dalian National Laboratory for Clean Energy Dalian116023China

Coal-fired power generation stands as the most economically viable modulating power source in present-day *** holds the potential to offer prospective solutions to the challenges posed by the rapid expansion of intermittent,unpredictable,and unstable renewable energy *** particle thermal storage technology emerges as an effective means to enhance the flexibility of coal-fired circulating fluidized bed power *** attain an optimized structure for the solid particle thermal storage and release system in circulating fluidized bed units,experimental research was conducted on a 0.1 MWth circulating fluidized bed test *** study delved into the impact of ash storage bin geometries and the shapes of their feed-discharge valves on the control properties of solid particle *** experimental outcomes reveal that employing inverted m-shaped valve and dual U-shaped valves for feed control,alongside U-shaped valves and N-shaped valves for discharge control,both enable efficient and rapid storage and release of solid particles within the circulating fluidized *** similar air distribution conditions,the inverted m-shaped valve exhibits lower conveying energy consumption than the dual U-shaped valves,while the N-shaped valve excels in control characteristics over the U-shaped ***,the inverted m-shaped valve and the N-shaped valve demonstrate optimal overflow port heights,and the ash storage bin exhibits an optimum height-to-diameter ratio.

关键词： Solid particle Thermal storage System structure Transport regulation

Cupping Therapy for Diseases: An Overview of Scientific Evidence from 2009 to 2019

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Chinese Journal of Integrative Medicine 2021年第5期27卷 394-400页

作者： WANG song-zi LU Yong-hui wu Min CHEN Ke-ji LIU Yue LIU Long-tao Department of Acupuncture and Moxibustion Xiyuan HospitalChina Academy of Chinese Medical SciencesBeijing 100091China General Department Guang’anmen HospitalChina Academy of Chinese Medical ScienceBeijing 100053China Department of Cardiovascular Diseases Xiyuan HospitalChina Academy of Chinese Medical SciencesBeijing 100091China

Cupping therapy has been accepted worldwide,and many studies have been conducted to reveal its curative effects and *** comprehensively evaluate the effect of cupping therapy,database including China Network Knowledge Infrastructure(CNKI),Chinese Scientific Journal Database VIP,Wan Fang Database,Chinese Biomedicine(CBM),Pub Med and Web of Science were searched from 2009–*** summarized all the meta-analyses,randomized controlled trials,clinical trials and the mechanisms studies of cupping therapy in the previous 10 years,hoping to provide a reference for the clinical applications and studies.

关键词： cupping overview clinical trial efficacy mechanism non-drug therapy

Degradation of microcystin-RR in water by chlorine dioxide

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Journal of China University of Mining and Technology 2008年第4期18卷 623-628页

作者： ji Ying HUANG Jun-li FU jiao wu Ming-song CUI Chong-wei School of Municipal and Environmental Engineering Harbin Institute of Technology Harbin Heilongjiang 150090 China

Due to the potent hepatotoxicity and tumor-promoting activity of microcystins, a successful removal of these toxins during drinking water treatment processes is of increasing concem. The oxidation kinetics of MC-RR by chlorine dioxide （ClO2） was studied with HPLC and characterization of the reaction products was performed with UV-spectrometry, TOC and LC-MS. Our experimental results show that the oxidation process is a second order overall and a first order with respect to ClO2 and MC-RR. The activation energy of MC-RR degradation by ClO2 is 53.07 kJ/mol. The rate constant k of the action can be increased by increasing temperature and decreasing pH value and ranged from 6.11 × 10^2 L/（***） to 5.29× 10^2 L/（mol-min） at pH from 3.44 to 10.41 at 10℃. Reaction products were determined to be organic and volatile, because they could be almost removed from aqueous solution by heating for 15 min at 60 ~C. In addition, the main oxidation products have m/z values of 1072 and are identified as dihydroxy isomers of MC-RR.

关键词： microcystin-RR ClO2 reaction kinetics UV-spectrometry TOC LC-MS

Effect of Air Distribution on the Transport Characteristics of Solid Particles in the Thermal Storage and Release System of Circulating Fluidized Bed

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Journal of Thermal Science 2024年第4期33卷 1554-1563页

作者： ji Zengcai song Guoliang TANG Zihua SUN Liwei State Key Laboratory of Coal Conversion Institute of Engineering ThermophysicsChinese Academy of SciencesBeijing100190China University of Chinese Academy of Sciences Beijing100049China Dalian National Laboratory for Clean Energy Dalian116023China

Solid particle heat storage technology offers a potential solution to the challenges posed by the significant growth of renewable energy sources,particularly in terms of grid security and ***,it has the capability to optimize the energy utilization efficiency of the power *** order to investigate the transport regulation characteristics of solid particles in the thermal storage and release system of a circulating fluidized bed(CFB),a test rig with a capacity of 0.1 MW(th)was *** rig was utilized to systematically study the transport regulation characteristics of solid particles under the double U-type valve feed structure and U-type valve discharge *** experimental findings indicate that the system's design enables efficient and rapid storage and release of solid particles in the *** air distribution mode,specifically the double U-type valve feed structure and the U-type valve discharge structure,significantly influence the feed and discharge characteristics of the ash storage *** was observed that the impact of loose air on these characteristics is more substantial than that of the return air,irrespective of the feed structure or the return *** adjusting the feed and discharge rate,it is recommended to adopt a scheme that involves coarse adjustment through loose air and fine adjustment through return air.

关键词： solid particle thermal storage air distribution mode transport regulation