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VLBI with SKA:Possible Arrays and Astrometric Science

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Research in Astronomy and Astrophysics 2024年第7期24卷 1-33页

作者： Yingjie Li Ye xu Jingjing Li Shuaibo Bian Zehao Lin Chaojie hao Dejian Liu Purple Mountain Observatory Chinese Academy of SciencesNanjing 210023China University of Science and Technology of China Hefei 230026China

The next generation of very long baseline interferometry(VLBI)is stepping into the era of microarcsecond(μas)astronomy,and pushing astronomy,especially astrometry,to new *** with the Square Kilometre Array(SKA),SKA-VLBI,will increase current sensitivity by an order of magnitude,and reach astrometric precision routinely below 10μas,even challenging 1μ*** advancement allows precise parallax and proper motion measurements of various celestial *** improvements can be used to study objects(including isolated objects,and binary or multiple systems)in different stellar stages(such as star formation,main-sequence stars,asymptotic giant branch stars,pulsars,black holes,white dwarfs,etc.),unveil the structure and evolution of complex systems(such as the Milky Way),benchmark the international celestial reference frame,and reveal cosmic ***,the theory of general relativity can also be tested with SKA-VLBI using precise measurements of light deflection under the gravitational fields of different solar system objects and the perihelion precession of solar system objects.

关键词： astrometry-parallaxes-stars kinematics and dynamics-ISM kinematics and dynamics-Galaxy kinematics and dynamics-galaxies kinematics and dynamics-gravitation

Quantitative Identification of Delamination Damage in Composite Structure Based on Distributed Optical Fiber Sensors and Model Updating

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Structural Durability & Health Monitoring 2024年第6期18卷 785-803页

作者： hao xu Jing Wang Rubin Zhu Alfred Strauss Maosen Cao Zhanjun Wu School of Materials Science and Engineering Dalian University of TechnologyDalian116000China School of Mechanics and Aerospace Engineering Dalian University of TechnologyDalian116000China Department of Civil Engineering and Natural Hazards University of Natural Resources and Life SciencesVienna1180Austria Department of Engineering Mechanics Hohai UniversityNanjingChina

Delamination is a prevalent type of damage in composite laminate *** accumulation degrades structural performance and threatens the safety and integrity of *** study presents a method for the quantitative identification of delamination identification in composite materials,leveraging distributed optical fiber sensors and a model updating ***,a numerical analysis is performed to establish a parameterized finite element model of the composite ***,this model subsequently generates a database of strain responses corresponding to damage of varying sizes and *** radial basis function neural network surrogate model is then constructed based on the numerical simulation results and strain responses captured from the distributed fiber optic ***,a multi-island genetic algorithm is employed for global optimization to identify the size and location of the *** efficacy of the proposed method is validated through numerical examples and experiment studies,examining the correlations between damage location,damage size,and strain *** findings confirm that the model updating technique,in conjunction with distributed fiber optic sensors,can precisely identify delamination in composite structures.

关键词： Composite structures fiber optic sensor damage identification model updating surrogate model

Promising real-time fruit and vegetable quality detection technologies applicable to manipulator picking process

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International Journal of Agricultural and Biological Engineering 2024年第2期17卷 14-26页

作者： Jintao Feng Qinyi Yang hao Tian Zhipeng Wang Shijie Tian Huirong xu College of Biosystems Engineering and Food Science Zhejiang UniversityHangzhou 310058China Key Laboratory of Intelligent Equipment and Robotics for Agriculture of Zhejiang Province Hangzhou 310058China

In recent years,worldwide research on fruit and vegetable quality detection technology includes machine vision,spectroscopy,acoustic vibration,tactile sensors,*** technologies have also been gradually applied to fruit and vegetable grading and sorting lines in recent years,greatly improving the income of *** have been numerous reviews of these *** of the published research on fruit and vegetable quality detection technology is still carried out in the *** emphases have been on quality feature extraction,model establishment and experimental *** successful application in the fruit and vegetable sorting production line proves that these studies have high application potential and value,and we look forward to the performance of these sensing technologies in the fruit and vegetable picking ***,in this paper,based on the future highly automated fruit and vegetable picking mode,we will focus on three kinds of fruit and vegetable quality detection technologies including machine vision,tactile sensor and spectroscopy,to provide some reference for future *** there are currently limited cases of detecting quality during the fruit and vegetable picking,experiments performed on prototypes of manipulator,or devices such as Nanocilia sensors,portable spectrometers,etc.,which are compact and convenient to mount on manipulator will be *** tables and mosaics showing the performance of the three technologies in the detection of fruit and vegetable quality over the past five years have been *** performance of each sensing technology was relatively satisfactory in the laboratory in ***,in the picking scenario,there are still many challenges to be *** from industrial environments,agricultural scenarios are complex and *** and vulnerable agricultural products pose another *** development of portable devices and nanomaterials have become important

关键词： fruit and vegetable quality detection machine vision spectroscopy tactile sensors picking scenario

Endoscopic polidocanol foam sclerobanding for the treatment of grade Ⅱ-Ⅲ internal hemorrhoids:A prospective,multi-center,randomized study

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World Journal of Gastroenterology 2024年第38期30卷 3326-3335页

作者： Chun-Ying Qu Fei-Yu Zhang Yi Zhang Ming-Ming Li Zheng-hong Li Mei-hong Cai Lei-Ming xu Feng Shen Wen Wang Wu-Lian Lin Feng-Yu Gao hao Zhang Guang-Yu Chen Department of Gastroenterology&Endoscopy Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of MedicineShanghai 200092China Department of Gastroenterology The 900th Hospital of the People’s Liberation Army Joint Service Support ForceFuzhou 350025Fujian ProvinceChina Department of Endoscopy Shandong Provincial Maternal and Child Health Care Hospital Affiliated to Qingdao UniversityJinan 250014Shandong ProvinceChina Department of Endoscopy Baoshan People’s Hospital of Yunnan ProvinceBaoshan 678000Yunnan ProvinceChina Department of Gastroenterology Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of MedicineShanghai 200092China

BACKGROUND Endoscopic rubber band ligation(ERBL)is a nonsurgical technique for the treatment of symptomatic internal hemorrhoids but is limited by recurrence and post-procedural *** To evaluate satisfaction,long-term recurrence,and post-procedural pain in managing internal hemorrhoids using a combination of polidocanol foam sclerotherapy and *** This was a prospective,multicenter,randomized study.A total of 195 consecutive patients diagnosed with grade II-III internal hemorrhoids were enrolled from four tertiary hospitals and randomly divided into a cap-assisted endoscopic polidocanol foam sclerobanding(EFSB)or an ERBL *** patients were followed-up for 12 ***-based severity and post-procedural pain were assessed using a hemorrhoid severity score(HSS)and a visual analog scale(VAS).Continuous variables were reported as medians and interquartile *** One hundred and ninety-five patients were enrolled,with 98 in the EFSB *** was lower in the EFSB group than in the ERBL group at 8 weeks[4.0(3.0-5.0)vs 5.0(4.0-6.0),P=0.003]and 12-month[2.0(1.0-3.0)vs 3.0(2.0-3.0),P<0.001]of *** prolapse recurrence rate was lower in the EFSB group at 12 months(11.2%vs 21.6%,P=0.038).Multiple linear regression analysis demonstrated that EFSB treatment[B=-0.915,95%confidence interval(CI):−1.301 to−0.530,P=0.001]and rubber band number(B=0.843,95%CI:0.595-1.092,P<0.001)were negatively and independently associated with the VAS score 24 hours *** median VAS was lower in the EFSB group than in the ERBL[2.0(1.0-3.0)vs 3.0(2.0-4.0),P<0.001].CONCLUSION Cap-assisted EFSB provided long-term satisfaction and effective relief from the recurrence of prolapse and pain 24 hours post-procedure.

关键词： Internal hemorrhoids Endoscopic therapy Polidocanol foam Sclerotherapy Rubber band ligation Sclerobanding

A pilot study on Paxlovid therapy for hemodialysis patients with severe acute respiratory syndrome coronavirus 2 infections

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Frontiers of Medicine 2024年第1期18卷 169-179页

作者： xu hao Zhiyao Bao Ranran Dai Xiaojing Wu Xin Li Muyin Zhang hao Li Lili xu Panpan Qiao xuefei Liu Weiting Hu Ze Zhang Jie Fang Min Zhou Weiming Wang Jieming Qu Department of Nephrology Ruijin HospitalShanghai Jiao Tong University School of MedicineShanghai200025China Department of Pulmonary and Critical Care Medicine Ruijin HospitalShanghai Jiao Tong University School of MedicineShanghai200025China Institute of Respiratory Diseases Shanghai Jiao Tong University School of MedicineShanghai200025China Department of Pharmacy Ruijin HospitalShanghai Jiao Tong University School of MedicineShanghai200025China

We aimed to investigate the safety and efficacy of nirmatrelvir/ritonavir(Paxlovid)therapy for hemodialysis-dependent patients with severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)*** hemodialysis patients infected with the Omicron variant of SARS-CoV-2 from April 3 to May 30,2022,were *** parameters and chest CT(computed tomography)imaging were *** treatment group included six patients who received 150 mg/100 mg of Paxlovid orally once daily for 5 days,whereas the control group included seven patients who received basic *** serious adverse reactions or safety events were *** control patients progressed to moderate disease,and none in the treatment group showed progression of chest CT findings(P<0.05).Paxlovid therapy tended toward early viral clearance and low viral load on Day ***,83.3%of the patients in the treatment group and 57.1%of the patients in the control group turned negative within 22 *** the Paxlovid treatment group,we found significantly increased levels of lymphocytes(P=0.03)and eosinophils(P=0.02)and decreased levels of D-dimer on Day 8 compared with those on Day *** therapy showed a potential therapeutic effect with good tolerance in hemodialysis *** optimal dose and effectiveness evaluation must be further investigated in a largeer cohort.

关键词： Paxlovid hemodialysis SARS-CoV-2 viral load chest CT scan

Room-temperature ferromagnetism and piezoelectricity in metalfree 2D semiconductor crystalline carbon nitride

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Nano Research 2024年第6期17卷 5670-5679页

作者： Yong Wang Dingyi Yang Wei xu Yongjie xu Yu Zhang Zixuan Cheng Yizhang Wu xuetao Gan Wei Zhong Yan Liu Genquan Han Yue hao Wide Bandgap Semiconductor Technology Disciplines State Key Laboratory School of MicroelectronicsAcademy of Advanced Interdisciplinary ResearchXidian UniversityXi’an 710071China Emerging Device and Chip Laboratory Hangzhou Institute of TechnologyXidian UniversityHangzhou 311200China INRS Centre for Energy Materials and Telecommunications1650 Boul.Lionel BouletVarennesQC J3X 1P7Canada National Laboratory of Solid State Microstructures Collaborative Innovation Center of Advanced Microstructures and Jiangsu Provincial Key Laboratory for NanotechnologyNanjing UniversityNanjing 210093China School of Education Jiangsu Open UniversityNanjing 210036China Department of Physics Shaanxi University of Science and TechnologyXi’an 710021China Department of Applied Physical Sciences The University of North Carolina at Chapel HillChapel HillNC 27514USA Key Laboratory of Light Field Manipulation and Information Acquisition Ministry of Industry and Information Technologyand Shaanxi Key Laboratory of Optical Information TechnologySchool of Physical Science and TechnologyNorthwestern Polytechnical UniversityXi'an 710129 China

Two-dimensional(2D)materials that combine ferromagnetic,semiconductor,and piezoelectric properties hold significant potential for both fundamental research and spin electronic ***,the majority of reported 2D ferromagnetic-semiconductor-piezoelectric materials rely on d-electron systems,which limits their practical applications due to a Curie temperature lower than room temperature(RT).Here,we report a high-crystallinity carbon nitride(CCN)material based on sp-electrons using a chemical vapor deposition *** exhibits a band gap of 1.8 eV and has been confirmed to possess substantial in-plane and out-of-plane ***,we acquired clear evidences of ferromagnetic behavior at room *** structural characterizations combined with theoretical calculations reveal that incorporating structural oxygen into the highly ordered heptazine structure causes partial substitution of nitrogen sites,which is primarily responsible for generating room-temperature ferromagnetism and *** a result,the strain in wrinkles can effectively modulate the domain behavior and piezoelectric potential at room *** addition of RT ferromagnetic-semiconductor-piezoelectric material based on sp-electrons to the family of two-dimensional materials opens up numerous possibilities for novel applications in fundamental research and spin electronic devices.

关键词： crystallinity carbon nitride room-temperature ferromagnetism piezoelectricity magnetic force microscopy density functional theory(DFT)calculations

Depositional process of hyperpycnal flow deposits:A case study on Lower Cretaceous Sangyuan outcrop in the Luanping Basin,Northeast China

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China Geology 2024年第3期7卷 505-516页

作者： De-zhi Yan Ru-kai Zhu hao Shou Zhao-hui xu Wei-hong Liu Si-cheng Zhu Zhi-cheng Lei Jing-ya Zhang Chang Liu Yi Cai Huai-min xu Research Institute of Petroleum Exploration and Development PetroChinaBeijing 100083China National Energy Tight Oil and Gas R&D Center Beijing 100083China PetroChina Key Laboratory of Oil and Gas Reservoir Beijing 100083China State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum(Beijing)Beijing 102249China College of Geosciences China University of Petroleum(Beijing)Beijing 102249China Jiangxi Engineering Laboratory on Radioactive Geoscience and Big Data Technology Department of Information and EngineeringEast China University of TechnologyNanchang 330013China

Sedimentary process research is of great significance for understanding the distribution and characteristics of *** the detailed observation and measurement of the Sangyuan outcrop in Luanping Basin,this paper studies the depositional process of the hyperpycnal flow deposits,and divides their depositional process into three phases,namely,acceleration,erosion and *** the acceleration phase,hyperpycnal flow begins to enter the basin nearby,and then speeds up *** developed in the acceleration phase are *** addition,the original deposits become unstable and are taken away by hyperpycnal flows under the eroding *** a result,there are a lot of mixture of red mud pebbles outside the basin and gray mud pebbles within the *** the erosion phase,the reverse deposits are eroded and become thinner or even ***,no reverse grading characteristic is found in the proximal major channel that is closer to the source,but it is still preserved in the middle branch channel that is far from the *** entering the deceleration phase,normally grading deposits appear and cover previous *** final deposits in the basin are *** are reverse,and others are *** are superimposed with each other under the action of hyperpycnal *** analysis of the Sangyuan outcrop demonstrates the sedimentary process and distribution of hyperpycnites,and reasonably explain the sedimentary characteristics of *** is helpful to the prediction of oil and gas exploration targets in gravity flow deposits.

关键词： Hyperpycnal flow Sedimentary characteristics Depositional process Gravity flow deposit Hyperpycnite Red mud pebble Gray mud pebble Oil and gas exploration engineering Luanping Basin

Design of Fully Automatic Specification Selection System for Resistance Welding Equipment

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Journal of Harbin Institute of Technology(New Series) 2024年第1期31卷 64-68页

作者： Xiangkun Lu Zengtai Tian hao xu Yue Guo The 707 Research Institute of CSSC Tianjin 300131China Tianjin 707 HI-TECH CO. LTDTianjin 300409China

A system for fully automatic selection of welding specifications in resistance welding equipment has been developed to address the problem of workers frequently choosing the wrong specifications during manual welding of multiple parts on a single machine in automobile factories. The system incorporates an automatic recognition system for different workpiece materials using the added machine fixture,visual detection system for nuts and bolts,and secondary graphical confirmation to ensure the correctness of specification calling. This system achieves reliable,fully automatic selection of welding specifications in resistance welding equipment and has shown significant effects in improving welding quality for massproduced workpieces,while solving the problem of specification calling errors that can occur with traditional methods involving process charts and code adjustments. This system is particularly suitable for promoting applications in manual welding of multiple parts on a single machine in automobile factories,ensuring correct specification calling and welding quality.

关键词： seat spot welding welding specifications fully automatic

Precipitation evolution and properties of Cu-15Ni-8Sn alloys via Al microalloying during ageing

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Rare Metals 2024年第10期43卷 5216-5228页

作者： Wei Luo Li-Jun Peng xu-Jun Mi hao-Feng Xie Yi-Cheng Cao Shu-Hui Huang State Key Laboratory of Nonferrous Metals and Processes GRINM Group Co.Ltd. GRIMAT Engineering Institute Co. Ltd. General Research Institute for Nonferrous Metals School of Materials Science and Engineering South China University of Technology

Studies have shown that microalloying Cu-Ni-Sn alloys using Al inhibits discontinuous precipitation reactions;however,the mechanism has not been investigated ***,this study explored the properties and precipitation evolution of Cu-15Ni-8Sn alloys without and with 1 wt%Al（Cu-15Ni-8Sn-1Al） during ageing at 500℃ through X-ray diffraction （XRD）,scanning electron microscopy and high-angle annular dark-field scanning transmission electron *** results revealed that in Cu-15Ni-8Sn alloy,DO22ordering first occurred after spinodal decomposition,subsequently transitioning to an L12ordering phase,during which the discontinuous precipitates gradually nucleated at the grain boundaries and formed *** alloy hardness increased sharply with ordering and then decreased rapidly after reaching its peak value,due to the dominance of the discontinuous precipitation ***,the DO22ordered phase did not appear during the ageing of Cu-15Ni-8Sn-1Al alloy,and a Ni3(Alx,Sn1-x) intermetallic compound with L12structure was formed,consuming Ni and Sn atoms,thereby significantly suppressing the discontinuous precipitation reaction and improving the stability during prolonged *** tensile strength （yield strength） of Cu-15Ni-8Sn and Cu-15Ni-8Sn-1Al alloys at peak hardness were 855 （755） and 936 MPa （892 MPa）,respectively,and their main strengthening mechanisms were solid solution strengthening and precipitation *** addition of 1 wt% Al effectively improved the precipitation strengthening effect of Cu-Ni-Sn alloys but severely decreased the ductility.

关键词： Al addition Cu-15Ni-8Sn Precipitation sequence Strengthening mechanism