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Bimagnetic metal constructed core-shell structure of Fe@Co nanowires for multi-band microwave absorption

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Progress in Natural Science:Materials International 2024年第2期34卷 354-361页

作者： ping-an Yang Rui cai Haibo Ruan Nanqing Zhang Xin Huang Rui Li Yuxin Zhang Yi Lu Zhihao Zhou School of Automation Chongqing University of Posts and Telecommunications Chongqing Key Laboratory of Materials Surface & Interface Science Chongqing University of Arts and Sciences College of Engineering and Technology Zunyi Normal College College of Material Science and Engineering Chongqing University

Controlled fabrication of materials by surface modification techniques has been a hot research topic. In this paper,one-dimensional(1D) core-shell structure Fe@Co nanowires(NWs) were successfully prepared by anchoring 0-dimensional(0D) Co nanoparticles on 1D Fe NWs based on the in situ reduction method. The electromagnetic parameters of the specimens at a filler mass fraction of 25 wt% were tested and the microwave loss mechanism was deeply analyzed. Binary magnetic metals in a core-shell structure have excellent multi-band microwave absorption capability(S-band, X-band and Ku-band). This is due to the heterogeneous interface and magnetic coupling effects tuning the dielectric and magnetic loss. This study offers a workable plan for creating effective multi-band magnetic metal-based microwave absorbers.

关键词： Core-shell structure Interface Magnetic coupling Microwave absorption One-dimensional nanowires

Differences and Correlations of Morphological and Hemodynamic Parameters between Anterior Circulation Bifurcation and Side-wall Aneurysms

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Current Medical Science 2024年第2期44卷 391-398页

作者： Kai-kai GUO Chang-ya LIU Gao-hui LI Jian-ping XIANG Xiao-chang LENG Yi-ke cai Xue-bin HU Department of Neurosurgery Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430022China Department of Emergency Longhua HospitalShanghai University of Traditional Chinese MedicineShanghai 200032China Artery Flow Technology Co. Ltd.Hangzhou 310051China

Objective:The objective of this research was to explore the difference and correlation of the morphological and hemodynamic features between sidewall and bifurcation aneurysms in anterior circulation arteries,utilizing computational fluid dynamics as a tool for analysis.Methods:In line with the designated inclusion criteria,this study covered 160 aneurysms identified in 131 patients who received treatment at Union Hospital of Tongji Medical College,Huazhong University of Science and Technology,China,from January 2021 to September 2022.Utilizing follow-up digital subtraction angiography(DSA)data,these cases were classified into two distinct groups:the sidewall aneurysm group and the bifurcation aneurysm group.Morphological and hemodynamic parameters in the immediate preoperative period were meticulously calculated and examined in both groups using a three-dimensional DSA reconstruction model.Results:No significant differences were found in the morphological or hemodynamic parameters of bifurcation aneurysms at varied locations within the anterior circulation.However,pronounced differences were identified between sidewall and bifurcation aneurysms in terms of morphological parameters such as the diameter of the parent vessel(Dvessel),inflow angle(θF),and size ratio(SR),as well as the hemodynamic parameter of inflow concentration index(ICI)(P0.5,P<0.001).Conclusions:The significant differences in certain morphological and hemodynamic parameters between sidewall and bifurcation aneurysms emphasize the importance to contemplate variances in threshold values for these parameters when evaluating the risk of rupture in anterior circulation aneurysms.Whether it is a bifurcation or sidewall aneurysm,these disparities should be considered.The morphological parameter SR has the potential to be a valuable clinical tool for promptly distinguishing

关键词： sidewall bifurcation unruptured aneurysms computational fluid dynamics

Expression and clinical significance of short-chain fatty acids in patients with intrahepatic cholestasis of pregnancy

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World Journal of Hepatology 2024年第4期16卷 601-611页

作者： Shuai-Jun Ren Jia-Ting Feng Ting Xiang cai-Lian Liao Yu-ping Zhou Rong-Rong Xuan Department of Obstetrics and Gynecology The First Affiliated Hospital of Ningbo UniversityNingbo 315100Zhejiang ProvinceChina Health Science Center Ningbo UniversityNingbo 315211Zhejiang ProvinceChina Department of Gastroenterology The First Affiliated Hospital of Ningbo UniversityNingbo 315211Zhejiang ProvinceChina Institute of Digestive Disease Ningbo UniversityNingbo 315020Zhejiang ProvinceChina

BACKGROUND Intrahepatic cholestasis of pregnancy(ICP)is a pregnancy-specific liver condition that typically arises in the middle and late stages of pregnancy.Short-chain fatty acids(SCFAs),prominent metabolites of the gut microbiota,have significant connections with various pregnancy complications,and some SCFAs hold potential for treating such complications.However,the metabolic profile of SCFAs in patients with ICP remains unclear.AIM To investigate the metabolic profiles and differences in SCFAs present in the maternal and cord blood of patients with ICP and determine the clinical significance of these findings.METHODS Maternal serum and cord blood samples were collected from both patients with ICP(ICP group)and normal pregnant women(NP group).Targeted metabolomics was used to assess the SCFA levels in these samples.RESULTS Significant differences in maternal SCFAs were observed between the ICP and NP groups.Most SCFAs exhibited a consistent declining trend in cord blood samples from the ICP group,mirroring the pattern seen in maternal serum.Correlation analysis revealed a positive correlation between maternal serum SCFAs and cord blood SCFAs[r(Pearson)=0.88,P=7.93e-95].In both maternal serum and cord blood,acetic and caproic acids were identified as key metabolites contributing to the differences in SCFAs between the two groups(variable importance for the projection>1).Receiver operating characteristic analysis demonstrated that multiple SCFAs in maternal blood have excellent diagnostic capabilities for ICP,with caproic acid exhibiting the highest diagnostic efficacy(area under the curve=0.97).CONCLUSION Compared with the NP group,significant alterations were observed in the SCFAs of maternal serum and cord blood in the ICP group,although they displayed distinct patterns of change.Furthermore,the SCFA levels in maternal serum and cord blood were significantly positively correlated.Notably,certain maternal serum SCFAs,specifically caproic and acetic acids,demonstrated excellent diagnostic efficiency for ICP.

关键词： Intrahepatic cholestasis of pregnancy Short-chain fatty acids Maternal serum Cord blood Caproic acid

Remaining Useful Life Prediction Method for Multi-Component System Considering Maintenance:Subsea Christmas Tree System as A Case Study

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China Ocean Engineering 2024年第2期38卷 198-209页

作者： WU Qi-bing cai Bao-ping FAN Hong-yan WANG Guan-nan RAO Xi GE Weifeng SHAO Xiao-yan LIU Yong-hong CNOOC Safety Technology Services Co. Ltd.Tianjin 300456China College of Mechanical and Electronic Engineering China University of PetroleumQingdao 266580China CNOOC EnerTech Safety&Environmental Protection BranchTianjin 300456China

Maintenance is an important technical measure to maintain and restore the performance status of equipment and ensure the safety of the production process in industrial production,and is an indispensable part of prediction and health management.However,most of the existing remaining useful life(RUL)prediction methods assume that there is no maintenance or only perfect maintenance during the whole life cycle;thus,the predicted RUL value of the system is obviously lower than its actual operating value.The complex environment of the system further increases the difficulty of maintenance,and its maintenance nodes and maintenance degree are limited by the construction period and working conditions,which increases the difficulty of RUL prediction.An RUL prediction method for a multi-omponent system based on the Wiener process considering maintenance is proposed.The performance degradation model of components is established by a dynamic Bayesian network as the initial model,which solves the uncertainty of insufficient data problems.Based on the experience of experts,the degree of degradation is divided according to Poisson process simulation random failure,and different maintenance strategies are used to estimate a variety of condition maintenance factors.An example of a subsea tree system is given to verify the effectiveness of the proposed method.

关键词： remaining useful life Wiener process dynamic Bayesian networks maintenance subsea Christmas tree system

Automatic detection of small bowel lesions with different bleeding risks based on deep learning models

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World Journal of Gastroenterology 2024年第2期30卷 170-183页

作者： Rui-Ya Zhang Peng-Peng Qiang Ling-Jun cai Tao Li Yan Qin Yu Zhang Yi-Qing Zhao Jun-ping Wang Department of Gastroenterology The Fifth Clinical Medical College of Shanxi Medical UniversityTaiyuan 030012Shanxi ProvinceChina School of Computer and Information Technology Shanxi UniversityTaiyuan 030006Shanxi ProvinceChina School of Life Sciences and Technology Mudanjiang Normal UniversityMudanjiang 157011Heilongjiang ProvinceChina

BACKGROUND Deep learning provides an efficient automatic image recognition method for small bowel(SB)capsule endoscopy(CE)that can assist physicians in diagnosis.However,the existing deep learning models present some unresolved challenges.AIM To propose a novel and effective classification and detection model to automatically identify various SB lesions and their bleeding risks,and label the lesions accurately so as to enhance the diagnostic efficiency of physicians and the ability to identify high-risk bleeding groups.METHODS The proposed model represents a two-stage method that combined image classification with object detection.First,we utilized the improved ResNet-50 classification model to classify endoscopic images into SB lesion images,normal SB mucosa images,and invalid images.Then,the improved YOLO-V5 detection model was utilized to detect the type of lesion and its risk of bleeding,and the location of the lesion was marked.We constructed training and testing sets and compared model-assisted reading with physician reading.RESULTS The accuracy of the model constructed in this study reached 98.96%,which was higher than the accuracy of other systems using only a single module.The sensitivity,specificity,and accuracy of the model-assisted reading detection of all images were 99.17%,99.92%,and 99.86%,which were significantly higher than those of the endoscopists’diagnoses.The image processing time of the model was 48 ms/image,and the image processing time of the physicians was 0.40±0.24 s/image(P<0.001).CONCLUSION The deep learning model of image classification combined with object detection exhibits a satisfactory diagnostic effect on a variety of SB lesions and their bleeding risks in CE images,which enhances the diagnostic efficiency of physicians and improves the ability of physicians to identify high-risk bleeding groups.

关键词： Artificial intelligence Deep learning Capsule endoscopy Image classification Object detection Bleeding risk

Effect of Fluoride on the Ion-association of Calcium Phosphate and Crystallization of Hydroxyapatite

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Journal of Wuhan University of Technology(Materials Science) 2024年第4期39卷 831-838页

作者：宋昊月 cai Meng 袁萍邹朝勇 School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070China State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China

Using a titration setup to accurately control the reaction conditions and in situ monitor the reaction,we showed that fluoride exhibited negligible effects on the ion association process of calcium and phosphate and the formation of ACP nanospheres in a buffer solution with constant ionic strength.However,the stability of ACP increased with increasing fluoride concentration,which was ascribed to the inhibitory effect of fluoride on the aggregation of ACP nanospheres and the nucleation of nanocrystals on the surface of ACP nanospheres.Furthermore,fluoride could inhibit the lateral growth of HAP nanosheets and promote the formation of rod-like crystals.These results further improve our understanding of the crystallization pathway of HAP crystals and the regulatory effects of fluoride.

关键词： crystallization amorphous calcium phosphate hydroxyapatite fluoride

Prediction of contact resistance of electrical contact wear using different machine learning algorithms

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Friction 2024年第6期12卷 1250-1271页

作者： Zhen-bing cai Chun-lin LI Lei YOU Xu-dong CHEN Li-ping HE Zhong-qing CAO Zhi-nan ZHANG Tribology Research Institute Southwest Jiaotong UniversityChengdu 610031China State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong UniversityShanghai 200240China

H62 brass material is one of the important materials in the process of electrical energy transmission and signal transmission,and has excellent performance in all aspects.Since the wear behavior of electrical contact pairs is particularly complex when they are in service,we evaluated the effects of load,sliding velocity,displacement amplitude,current intensity,and surface roughness on the changes in contact resistance.Machine learning(ML)algorithms were used to predict the electrical contact performance of different factors after wear to determine the correlation between different factors and contact resistance.Random forest(RF),support vector regression(SVR)and BP neural network(BPNN)algorithms were used to establish RF,SVR and BPNN models,respectively,and the experimental data were trained and tested.It was proved that BP neural network model could better predict the stable mean resistance of H62 brass alloy after wear.Characteristic analysis shows that the load and current have great influence on the predicted electrical contact properties.The wear behavior of electrical contacts is influenced by factors such as load,sliding speed,displacement amplitude,current intensity,and surface roughness during operation.Machine learning algorithms can predict the electrical contact performance after wear caused by these factors.Experimental results indicate that an increase in load,current,and surface roughness leads to a decrease in stable mean resistance,while an increase in displacement amplitude and frequency results in an increase in stable mean resistance,leading to a decline in electrical contact performance.To reduce testing time and costs and quickly obtain the electrical contact performance of H62 brass alloy after wear caused by different factors,three algorithms(random forest(RF),support vector regression(SVR),and BP neural network(BPNN))were used to train and test experimental results,resulting in a machine learning model suitable for predicting the stable mean resistance of H62 brass alloy after wear.The pr

关键词： electrical contact wear contact resistance machine learning(ML) neural network

Design and performance evaluation of a large field-of-view dual-particle time-encoded imager based on a depth-of-interaction detector

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Nuclear Science and Techniques 2024年第4期35卷 1-14页

作者： Dong Zhao Xu-Wen Liang ping-Kun cai Wei Cheng Wen-Bao Jia Da-Qian Hei Qing Shan Yong-Sheng Ling Chao Shi Department of Nuclear Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 211106China Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions Suzhou 215000China School of Nuclear Science and Technology Lanzhou UniversityLanzhou 730000China

Time-encoded imaging is useful for identifying potential special nuclear materials and other radioactive sources at a distance.In this study,a large field-of-view time-encoded imager was developed for gamma-ray and neutron source hotspot imaging based on a depth-of-interaction(DOI)detector.The imager primarily consists of a DOI detector system and a rotary dual-layer cylindrical coded mask.An EJ276 plastic scintillator coupled with two SiPMs was designed as the DOI detector to increase the field of view and improve the imager performance.The difference in signal time at both ends and the log of the signal amplitude ratio were used to calculate the interaction position resolution.The position resolution of the DOI detector was calibrated using a collimated Cs-137 source,and the full width at half maximum of the reconstruction position of the Gaussian fitting curve was approximately 4.4 cm.The DOI detector can be arbitrarily divided into several units to independently reconstruct the source distribution images.The unit length was optimized via Am-Be source-location experiments.A multidetector filtering method is proposed for image denoising.This method can effectively reduce image noise caused by poor DOI detector position resolution.The vertical field of view of the imager was(-55°,55°)when the detector was placed in the center of the coded mask.A DT neutron source at 20 m standoff could be located within 2400 s with an angular resolution of 3.5°.

关键词： Time-encoded imager Depth-of-interaction detector Dual-particle imaging Hotspot imaging

Milestone progress of the HEPS booster commissioning

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Nuclear Science and Techniques 2024年第1期35卷 170-177页

作者： yue-Mei Peng Jian-She Cao Jin-Hui Chen Hai-Yi Dong ping He Yi Jiao Ling Kang Wen Kang Jian Li Jing-Yi Li Guo-ping Lin Fang Liu Feng-Li Long cai Meng Xin Qi Hua-Min Qu Yan-Feng Sui Sheng Wang Gang Xu Qiang Ye Jing Zhang Pei Zhang Wei-Min Pan Key Laboratory of Particle Acceleration Physics and Technology Institute of High Energy PhysicsChinese Academy of Sciences19B Yuquan RoadShijingshan DistrictBeijing 100049China University of the Chinese Academy of Sciences 19A Yuquan RoadShijingshan DistrictBeijing 100049China

The high-energy photon source(HEPS)is the first fourth-generation synchrotron light source facility in China.The HEPS injector consists of a linear accelerator(Linac)and a full energy booster.The booster captures the electron beam from the Linac and increases its energy to the value required for the storage ring.The full-energy beam could be injected to the storage ring directly or after“high-energy accumulation.”On November 17,2023,the key booster parameters successfully reached their corresponding target values.These milestone results were achieved based on numerous contributions,including nearly a decade of physical design,years of equipment development and installation,and months of beam commissioning.As measured at the extraction energy of 6 GeV,the averaged beam current and emittance reached 8.57 mA with 5 bunches and 30.37 nm rad with a single-bunch charge of 5.58 nC,compared with the corresponding target values of 6.6 mA and 35 nm rad,respectively.This paper presents the physical design,equipment development,installation,and commissioning process of the HEPS booster.

关键词： High energy photon source Booster Beam commissioning