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Testing results analysis of contact materials’electrical contact performance

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第3期8卷 459-463页

作者： WANG Jing-qin WANG Hai-tao WEN ming ZHU yan-cai Institute of Electrical Apparatus Hebei University of Technology Tianjin 300130 China

Because of the different ways in which contact materials work, the basic requirements for silver metal oxide contact materials are different. They are anti-welded and anti-erosion when closed, anti-erosion when broken, and arc easily moved and have smaller contact resistance. In this paper, La2O3 is used as a stable oxide in contact material to replace CdO. A new type of Ag/SnO2-La2O3-Bi2O3 contact material is first obtained through using powder metallurgical method. Then electrical contact material parameter tester is used to test the electrical contact performance of the contact material. Through experiments, the arcing voltage and current curves, arcing energy curves, fusion power curves while broken and contact resistance while closed were obtained. Analysis of the results showed that the addition of La2O3 makes the contact material have the following advantages: smaller electrical wear, smaller arc energy, smaller contact resistance and arc is more easily extinguished.

关键词： Ag/SnO2-La2O3-Bi2O3 Contact materials Electrical contact performance

A Theory and Method for Modeling of Structures with Stochastic Parameters

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上海交通大学学报 2004年第Z2期38卷 194-198页

作者： ZHANG Bei YIN Xue-gang WANG Fu-ming ZHONG yan-hui cai Ying-chun Chonging University Chongqing400044 P. R. China Zhengzhou University Zhengzhou450002 P. R. China Chonging University Chongqing400044 P. R. China Zhengzhou University Zhengzhou450002 P. R. China Zhengzhou University Zhengzhou450002 P. R. China Dalian University of Technology Dalian116024 P. R. China Zhengzhou University Zhengzhou450002 P. R. China Dalian University of Technology Dalian116024 P. R. China

In order to reflect the stochastic characteristics of structures more comprehensively and accurately, a theory and method for modeling of structures with stochastic parameters is presented by using probability finite element method and stochastic experiment data of structures based on the modeling of structures with deterministic parameters. Double-decker space frame is taken as an example to validate this theory and method, good results are gained.

关键词： probability finite element method stochastic parameter structure modeling

An esophageal submucosal tumor treated with submucosal tunneling endoscopic resection:an unexpected result

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Gastroenterology Report 2021年第3期9卷 269-271,I0003页

作者： ming-yan cai Mariana Ferreira Cardoso yan Zhu Yun-Shi Zhong Ping-Hong Zhou Endoscopy Center Zhongshan HospitalFudan UniversityShanghaiP.R.China Gastroenterology Department Hospital Professor Doutor Fernando FonsecaAmadoraPortugal

Case presentation A 66-year-old female patient underwent esophagogastroduodenoscopy(EGD)in our center because of occasional dysphagia,and a large submucosal tumor(SMT)was identified 32–36cm from the incisors,occupying nearly half of the luminal circumference(Figure 1A).Mini-probe endoscopic ultrasonography(EUS)revealed a hypoechoic submucosal lesion,measuring 20×15mm and originating from the superficial muscularis propria layer(Figure 1B).It was covered by normal-appearing mucosa.

关键词：食管黏膜下肿瘤 superficial Figure

Base-controlled NHC-Ru-catalyzed transfer hydrogenation andα-methylation/transfer hydrogenation of ketones using methanol

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Chinese Chemical Letters 2024年第7期35卷 276-280页

作者： ming Huang Xiuju cai yan Liu Zhuofeng Ke School of pharmacy School of clinical pharmacyGuangdong Pharmaceutical UniversityGuangzhou 510006China School of Materials Science&Engineering PCFM LabSchool of ChemistrySun Yat-sen UniversityGuangzhou 510275China School of Chemical Engineering and Light Industry Guangdong University of TechnologyGuangzhou 510006China

Herein,we report the NHC-Ru catalyst system that realizes the chemo-selective transformation of ketones with *** simply changing the base,a broad range of structurally diverse ketones,could be selectively and efficiently converted to the correspondingβ-methylated secondary alcohols or secondary ***,this catalytic system was very effective for the synthesis of bio-related molecules and deuterated alcohols,as well as the three-component coupling between methyl ketones,primary alcohols,and *** reaction mechanism was further revealed by experiment and DFT mechanistic investigations.

关键词： Ru complexes Methanol Ketones β-Methylated secondary alcohols Transfer hydrogenation

Two-Staged Method for Ice Channel Identification Based on Image Segmentation and Corner Point Regression

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China Ocean Engineering 2024年第2期38卷 313-325页

作者： DONG Wen-bo ZHOU Li DING Shi-feng WANG Ai-ming cai Jin-yan School of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China School of Naval Architecture Ocean and Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China

Identification of the ice channel is the basic technology for developing intelligent ships in ice-covered waters,which is important to ensure the safety and economy of *** the Arctic,merchant ships with low ice class often navigate in channels opened up by *** in the ice channel often depends on good maneuverability skills and abundant experience from the captain to a large *** ship may get stuck if steered into ice fields off the *** this circumstance,it is very important to study how to identify the boundary lines of ice channels with a reliable *** this paper,a two-staged ice channel identification method is developed based on image segmentation and corner point *** first stage employs the image segmentation method to extract channel *** the second stage,an intelligent corner regression network is proposed to extract the channel boundary lines from the channel region.A non-intelligent angle-based filtering and clustering method is proposed and compared with corner point regression *** training and evaluation of the segmentation method and corner regression network are carried out on the synthetic and real ice channel *** evaluation results show that the accuracy of the method using the corner point regression network in the second stage is achieved as high as 73.33%on the synthetic ice channel dataset and 70.66%on the real ice channel dataset,and the processing speed can reach up to 14.58frames per second.

关键词： ice channel ship navigation identification image segmentation corner point regression

Reveal the lost entanglement for accelerated atoms in the high-dimensional spacetime

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Science China(Physics,Mechanics & Astronomy) 2024年第6期67卷 48-57页

作者： Jiatong yan Baocheng Zhang Qingyu cai School of Mathematics and Physics China University of GeosciencesWuhan 430074China Physics Department Brown UniversityProvidenceRhode Island 02912USA Center for Theoretical Physics Hainan UniversityHaikou 570228China School of Information and Communication Engineering Hainan UniversityHaikou 570228China Peng Huanwu Center for Fundamental Theory Hefei 230026China

When atoms are accelerated in the vacuum,entanglement among atoms will degrade compared with the initial situation before the *** this study,we propose a novel and interesting view that the lost entanglement can be recovered completely when the high-dimensional spacetime is exploited,in the case that the acceleration is not too large,since the entanglement loss rate caused by the large acceleration is faster than the recovery *** also calculate the entanglement change caused by the anti-Unruh effect and found that the lost entanglement could just be recovered part by the anti-Unruh effect,and the anti-Unruh effect could only appear for a finite range of acceleration when the interaction time scale is approximately shorter than the reciprocal of the energy gap in two dimensional *** limit case of zero acceleration is also investigated,which gives an analytical interpretation for the increase or recovery of entanglement.

关键词： entanglement acceleration high-dimensional spacetime

The efficacy of full-thickness endoscopic resection of subepithelial tumors in the gastric cardia

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World Journal of Gastrointestinal Oncology 2023年第12期15卷 2111-2119页

作者： En-Pan Xu Zhi-Peng Qi Bing Li Zhong Ren ming-yan cai Shi-Lun cai Zhen-Tao Lyv Zhang-Han Chen Jing-Yi Liu Qiang Shi Yun-Shi Zhong Endoscopy Center Zhongshan Hospital Fudan UniversityShanghai 200032China

BACKGROUND Gastric subepithelial tumors(SETs)may harbor potential *** it is well recognized that large SETs should be resected,the precise treatment strategy remains *** to surgical resection,endoscopic resection(ER)has many advantages;however,ER of SETs in the cardia is *** To evaluate the safety and efficacy of endoscopic full-thickness resection(EFTR)for the treatment of gastric cardia *** We retrospectively reviewed data from all patients with SETs originating from the muscularis propria layer in the gastric cardia that were treated by EFTR or submucosal tunneling ER(STER)at Zhongshan Hospital Fudan University between November 2014 and May *** characteristics and clinical outcomes,including procedure times and complications rates,were compared between groups of patients receiving EFTR and *** A total of 171 tumors were successfully removed[71(41.5%)tumors in the EFTR and 100(58.5%)tumors in the STER group].Gastrointestinal stromal tumors(GISTs)were the most common *** en bloc resection rate was 100%in the EFTR group vs 97.0%in STER group(P>0.05).Overall,the EFTR group had a higher complete resection rate than the STER group(98.6%vs 91.0%,P<0.05).The procedure time was also shorter in the EFTR group(44.63±28.66 min vs 53.36±27.34,P<0.05).The most common major complication in both groups was electrocoagulation *** was no significant difference in total complications between the two groups(21.1%vs 22.0%,P=0.89).CONCLUSION EFTR of gastric cardia SETs is a very promising method to facilitate complete resection with similar complications and reduced operative times compared to *** cases of suspected GISTs or an unclear diagnosis,EFTR should be recommended to ensure complete resection.

关键词： Endoscopic full-thickness resection Submucosal tunneling endoscopic resection Gastrointestinal stromal tumor Gastric cardia Gastric subepithelial tumors

Heterointerface Engineering-Induced Oxygen Defects for the Manganese Dissolution Inhibition in Aqueous Zinc Ion Batteries

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Energy & Environmental Materials 2024年第3期7卷 112-122页

作者： Wentao Qu Yong cai Baohui Chen ming Zhang Hunan Provincial Key Laboratory of Low-Dimensional Structural Physics&Devices School of Physics and ElectronicsHunan UniversityChangsha 410082China Engineering Research Center of Advanced Semiconductor Technology and Application of Ministry of Education&Key Laboratory for Micro-/Nano-Optoelectronic Devices of Ministry of Education College of Semiconductors(College of Integrated Circuits)Hunan UniversityChangsha 410082China Changsha Semiconductor Technology and Application Innovation Research Institute College of Semiconductors(College of Integrated Circuits)Hunan UniversityChangsha 410082China State Key Laboratory of Disaster Prevention&Reduction for Power Grid Transmission and Distribution Equipment(Hunan Electric Power Corporation Disaster Prevention and Reduction Center) Changsha 410007China

Manganese-based material is a prospective cathode material for aqueous zinc ion batteries(ZIBs)by virtue of its high theoretical capacity,high operating voltage,and low ***,the manganese dissolution during the electrochemical reaction causes its electrochemical cycling stability to be *** this work,heterointerface engineering-induced oxygen defects are introduced into heterostructure MnO_(2)(δa-MnO_(2))by in situ electrochemical activation to inhibit manganese dissolution for aqueous zinc ion ***,the heterointerface between the disordered amorphous and the crystalline MnO_(2)ofδa-MnO_(2)is decisive for the formation of oxygen *** the experimental results indicate that the manganese dissolution ofδa-MnO_(2)is considerably inhibited during the charge/discharge *** analysis indicates that the oxygen defect regulates the electronic and band structure and the Mn-O bonding state of the electrode material,thereby promoting electron transport kinetics as well as inhibiting Mn ***,the capacity ofδa-MnO_(2)does not degrade after 100 cycles at a current density of 0.5 Ag^(-1)and also 91%capacity retention after 500cycles at 1 Ag^(-1).This study provides a promising insight into the development of high-performance manganese-based cathode materials through a facile and low-cost strategy.

关键词： electrochemical activation heterointerface manganese dissolution inhibition oxygen defects zinc ion batteries

BSEC Method for Unveiling Open Clusters and its Application to Gaia DR3:83 New Clusters

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Research in Astronomy and Astrophysics 2024年第5期24卷 169-184页

作者： Zhong-Mu Li cai-yan Mao Institute of Astronomy and Information Dali UniversityDali 671003China

Open clusters(OCs) are common in the Milky Way, but most of them remain undiscovered. There are numerous techniques, including some machine-learning algorithms, available for the exploration of OCs. However, each method has its limitations and therefore, different approaches to discovering OCs hold significant values. We develop a comprehensive approach method to automatically explore the data space and identify potential OC candidates with relatively reliable membership determination. This approach combines the techniques of Hierarchical Density-Based Spatial Clustering of Applications with Noise, Gaussian mixture model, and a novel cluster member identification technique, color excess constraint. The new method exhibits efficiency in detecting OCs while ensuring precise determination of cluster memberships. Because the main feature of this technique is to add an extra constraint(EC) for the members of cluster candidates using the homogeneity of color excess,compared to typical blind search codes, it is called Blind Search-Extra Constraint(BSEC) method. It is successfully applied to the Gaia Data Release 3, and 83 new OCs are found, whose color–magnitude diagrams(CMDs) are fitted well to the isochrones. In addition, this study reports 621 new OC candidates with discernible main sequence or red giant branch. It is shown that BSEC technique can discard some false negatives of previous works, which takes about three percentage of known clusters. It shows that as an EC, the color excess(or twocolor) constraint is useful for removing fake cluster member stars from the clusters that are identified from the positions and proper motions of stars, and getting more precise CMDs, when differential reddening of member stars of a cluster is not large(e.g., ΔE(G_(BP)-G_(RP)) < 0.5 mag). It makes the CMDs of 15% clusters clearer(in particular for the region near turnoff) and therefore is helpful for CMD and stellar population studies. Our result suggests that the color excess con

关键词： Galaxy stellar content-(Galaxy:)open clusters and associations general-stars fundamental parameters