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Journal of Iron and Steel Research International 2024年第3期31卷 767-777页

作者： Hong-bin Dai jian Miao jia-xin lin School of Materials Science and Engineering Harbin University of Science and TechnologyHarbin 150040HeilongjiangChina

The welding arc,as a carrier for the conversion of electrical energy to thermal energy,has a direct impact on the quality of welding by its properties and *** the tungsten inert gas(TIG)welding process under the condition of Ar-He alternating gas supply,the arc is alternately converted between Ar arc and He arc with an alternating gas supply cycle,which has obvious arc change *** FLUENT software was used to numerically simulate the characteristics of the TIG arc under the condition of alternating gas supply,and the arc temperature field,arc pressure,electric potential and current density distribution under the condition of alternating gas supply were *** with the real-time data of arc pressure measured by the water-cooled copper plate with holes,it is proved that the TIG arc has obvious dynamic characteristics under the condition of Ar-He alternating gas *** unique dynamic TIG arc acts on the 5A06 aluminum alloy weld,causing the molten pool to stir,resulting in uniform microstructure and grain refinement at the weld,and thereby improving the mechanical properties of the welded joint.

关键词： Alternating gas supply Grain refinement Numerical simulation Tungsten argon arc morphology Microstructure Mechanical property

Rheological Behaviors of Polymers with Nanoparticles Tethered at Each End

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Chinese Journal of Polymer Science 2024年第3期42卷 400-406,I0009页

作者： Song-Qi Zhang Wen-Qing Wang jia-Ping lin Li-Quan Wang Shanghai Key Laboratory of Advanced Polymeric Materials Key Laboratory for Ultrafine Materials of Ministry of EducationSchool of Materials Science and EngineeringEast China University of Science and TechnologyShanghai 200237China

The polymer with nanoparticles tethered at each end is a unique model for unraveling the effect of chain ends on the polymer dynamics. We investigated the rheological behavior of this kind of polymer by using nonequilibrium molecular dynamics simulation. The effect of polymer lengths and nanoparticle radii on the complex moduli and viscosity was examined. The dependence of complex moduli on the frequency becomes less pronounced as the polymer is short or the nanoparticle is large. The shear thinning behavior was revealed for these systems, and the scaling exponent of complex viscosity with respect to the frequency was found to change from-1/2 to-3/4 as the polymer shortens or the nanoparticle enlarges. The rheological behavior was further explained by analyzing the mean square distance of nanoparticles. The simulation results were compared with the existing experimental finding, showing an agreement. The work provides information for understanding the chain end effect on polymer rheology.

关键词： Polymer rheology Modulus Viscosity Molecular dynamics

Train wheel-rail force collaborative calibration based on GNN-LSTM

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High-Speed Railway 2024年第2期2卷 85-91页

作者： Changfan Zhang Zihao Yu lin jia College of Railway Transportation Hunan University of TechnologyZhuzhou 412007China College of Electrical and Information Engineering Hunan University of TechnologyZhuzhou 412007China

Accurate wheel-rail force data serves as the cornerstone for analyzing the wheel-rail ***,achieving continuous and precise measurement of this force remains a significant challenge in the *** article introduces a calibration algorithm for the wheel-rail force that leverages graph neural networks and long short-term memory ***,a comprehensive wheel-rail force detection system for trains was constructed,encompassing two key components:an instrumented wheelset and a ground wheel-rail force measuring ***,utilizing this system,two distinct datasets were acquired from the track inspection vehicle:instrumented wheelset data and ground wheel-rail force data,a feedforward neural network was employed to calibrate the instrumented wheelset data,referencing the ground wheel-rail force ***,ground wheel-rail force data for the locomotive was obtained for the corresponding road *** data was then integrated with the calibrated instrumented wheelset data from the track inspection *** the GNN-LSTM network,the article establishes a mapping relationship model between the wheel-rail force of the track inspection vehicle and the locomotive wheel-rail *** model facilitates continuous measurement of locomotive wheel-rail forces across three typical scenarios:straight sections,long and steep downhill sections,and small curve radius sections.

关键词： Railway Wheel-rail force Deep learning Instrumented wheelset Ground wheel-rail force measuring system

Regulating photothermal properties of near-infrared croconaine dyes by supramolecular assembly

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Nano Research 2024年第9期17卷 8560-8570页

作者： Yangge Ren Yue Lu Juanjuan Gao Yi Ding Bo Zhu Xinyu Hou lin jia Department of Polymer Materials School of Materials Science and EngineeringShanghai UniversityShanghai 200444China Department of Electronic Information Materials School of Materials Science and EngineeringShanghai UniversityShanghai 200444China

The photochemical and photophysical properties of near-infrared(NIR)dyes are significantly influenced by their aggregation state and mesoscopic ***,beyond chemical synthesis,the regulation mechanisms for the properties of NIR dyes,particularly with respect to photothermal properties of the aggregates,are not yet fully ***,we investigate the photothermal behaviors of croconaine-based(CroA)NIR dyes containing dipeptide or amino acids *** introduction of hydrogen bonding promotesπ-πstacking of croconaine center,which can efficiently regulate aggregation states and assembly structures in *** laser irradiation,CroA aggregates undergo aggregation-dissociation transition,the in-situ monomer generation process regulates two parameters of photothermal performance:heating rates and plateau photothermal *** study reveals the regulation effect of non-covalent bonding interactions on CroA aggregates,highlighting supramolecular assembly strategy not only facilitates to construct of photothermal nanomaterials with well-defined structures,but also provides an alternative and effective method for regulating photothermal performance of NIR dyes.

关键词： croconaine dye hydrogen bonding photothermal performance supramolecular assembly chirality

Postpartum quality of life and mental health in women with heart disease:Integrated clinical communication and treatment

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World Journal of Psychiatry 2024年第1期14卷 63-75页

作者： jia-lin Liu Qi Wang Dong-Ying Qu Department of Obstetrics and Gynecology China Medical UniversityShenyang 110122Liaoning ProvinceChina Department of Psychiatry General Hospital of Northern Theater CommandShenyang 110016Liaoning ProvinceChina Department of Obstetrics and Gynecology General Hospital of Northern Theater CommandShenyang 110016Liaoning ProvinceChina

BACKGROUND Postpartum quality of life(QoL)in women with heart disease has been *** To improve clinical communication and treatment,we integrated medical data and subjective characteristics to study postpartum QoL *** The study assessed QoL 6 wk after birth using the 12-Item Short-Form Health *** Edinburgh Postnatal Depression Scale,Cardiac Anxiety Questionnaire,European Heart Failure Self-Care Behavior Scale,and a self-designed questionnaire based on earlier research were also used to assess patient *** data were *** models were created using multiple linear *** This retrospective study examined postpartum QoL in 105 cardiac *** QoL scores were lower(90.69±13.82)than those of women without heart disease,with physical component scores(41.09±9.91)lower than mental component scores(49.60±14.87).Postpartum depression(33.3%),moderate anxiety(37.14%),pregnancy concerns(57.14%),offspring heart problems(57.14%),and life expectancy worries(48.6%)were all *** previous cardiac surgery,multiparity,higher sadness and cardiac anxiety,and fear of unfavorable pregnancy outcomes were strongly related to lower QoL(R^(2)=0.525).CONCLUSION Postpartum QoL is linked to physical and mental health in women with heart *** study emphasizes the need for healthcare workers to recognize the unique characteristics of these women while developing and implementing comprehensive management approaches during their maternity care.

关键词： Heart disease Pregnancy Postpartum Quality of life Mental health

Normal sperm head morphometric reference values in fertile Asian males

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Asian Journal of Andrology 2024年第3期26卷 315-320页

作者： Ye-lin jia Ying-Bi Wu lin Yu Yan Zheng Ting-Ting Yang Yan-Yun Wang Bin Zhou lin Zhang Fu-Ping Li Laboratory of Andrology West China Second University Hospital Human Sperm BankChengdu 610000China Laboratory of Molecular Translational Medicine Center for Translational MedicineChengdu 610061China Key Laboratory of Birth Defects and Related Diseases of Women and Children(Sichuan University) Ministry of EducationChengdu 610061China NHC Key Laboratory of Chronobiology West China Second University HospitalSichuan UniversityChengdu 610000China

Sperm head morphology is crucial for male factor infertility diagnosis and assessment of male reproductive *** are available to analyze sperm head morphology,but they are limited by poor methodology comparability and *** study aimed to explore comprehensive and new normal morphometric reference values for spermatozoa heads infertile Asian *** automated sperm morphology analysis system captured 23152 stained spermatozoa from confirmed *** these samples,1856 sperm head images were annotated by three experienced laboratory technicians as“normal”.Weemployed 14 novel morphometric features to describe sperm head size(head length,head width,length/width ratio,and girth),shape(ellipse intersection over union,girth intersection over union,short-axis symmetry,and long-axis symmetry),area(head,acrosome,postacrosomal areas,and acrosome area ratio),and degrees of acrosome and nuclear *** straight-forwardmethod for the morphometric analysis of sperm by accurate visual measurements is clinically *** measured parameterspresent valuable information to establish morphometric reference intervals for normal sperm heads in fertile Asian *** detailed measurement data will be valuable for interlaboratory comparisons and technician *** vitro fertilizationand andrology laboratory technicians can use these parameters to perform objective morphology evaluation when assessing malefertilization potential.

关键词： fertile Asian males head morphometric reference value normal spermatozoa

Meibomian glands segmentation in infrared images with limited annotation

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International Journal of Ophthalmology(English edition) 2024年第3期17卷 401-407页

作者： jia-Wen lin ling-Jie lin Feng Lu Tai-Chen Lai Jing Zou lin-ling Guo Zhi-Ming lin Li Li College of Computer and Data Science Fuzhou UniversityFuzhou 350108Fujian ProvinceChina Fujian Provincial Key Laboratory of Networking Computing and Intelligent Information Processing Fuzhou UniversityFuzhou 350108Fujian ProvinceChina Shengli Clinical Medical College of Fujian Medical University Fuzhou 350001Fujian ProvinceChina Department of Ophthalmology Fujian Provincial Hospital South BranchFujian Provincial HospitalFuzhou 350001Fujian ProvinceChina

●AIM:To investigate a pioneering framework for the segmentation of meibomian glands(MGs),using limited annotations to reduce the workload on ophthalmologists and enhance the efficiency of clinical diagnosis.●METHODS:Totally 203 infrared meibomian images from 138 patients with dry eye disease,accompanied by corresponding annotations,were gathered for the study.A rectified scribble-supervised gland segmentation(RSSGS)model,incorporating temporal ensemble prediction,uncertainty estimation,and a transformation equivariance constraint,was introduced to address constraints imposed by limited supervision information inherent in scribble *** viability and efficacy of the proposed model were assessed based on accuracy,intersection over union(IoU),and dice coefficient.●RESULTS:Using manual labels as the gold standard,RSSGS demonstrated outcomes with an accuracy of 93.54%,a dice coefficient of 78.02%,and an IoU of 64.18%.Notably,these performance metrics exceed the current weakly supervised state-of-the-art methods by 0.76%,2.06%,and 2.69%,***,despite achieving a substantial 80%reduction in annotation costs,it only lags behind fully annotated methods by 0.72%,1.51%,and 2.04%.●CONCLUSION:An innovative automatic segmentation model is developed for MGs in infrared eyelid images,using scribble annotation for *** model maintains an exceptionally high level of segmentation accuracy while substantially reducing training *** holds substantial utility for calculating clinical parameters,thereby greatly enhancing the diagnostic efficiency of ophthalmologists in evaluating meibomian gland dysfunction.

关键词： infrared meibomian glands images meibomian gland dysfunction meibomian glands segmentation weak supervision scribbled annotation

Multi-Scale Mixed Attention Tea Shoot Instance Segmentation Model

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Phyton-International Journal of Experimental Botany 2024年第2期93卷 261-275页

作者： Dongmei Chen Peipei Cao Lijie Yan Huidong Chen jia lin Xin Li lin Yuan Kaihua Wu School of Automation Hangzhou Dianzi UniversityHangzhou310018China Tea Research Institute Chinese Academy of Agriculture SciencesHangzhou310018China School of Information Engineering Zhejiang University of Water Resources and Electric PowerHangzhou310018China

Tea leaf picking is a crucial stage in tea production that directly influences the quality and value of the *** tea-picking machines may compromise the quality of the tea ***-quality teas are often handpicked and need more delicate operations in intelligent picking *** with traditional image processing techniques,deep learning models have stronger feature extraction capabilities,and better generalization and are more suitable for practical tea shoot ***,current research mostly focuses on shoot detection and cannot directly accomplish end-to-end shoot segmentation *** propose a tea shoot instance segmentation model based on multi-scale mixed attention(Mask2FusionNet)using a dataset from the tea garden in *** further analyzed the characteristics of the tea shoot dataset,where the proportion of small to medium-sized targets is 89.9%.Our algorithm is compared with several mainstream object segmentation algorithms,and the results demonstrate that our model achieves an accuracy of 82%in recognizing the tea shoots,showing a better performance compared to other *** ablation experiments,we found that ResNet50,PointRend strategy,and the Feature Pyramid Network(FPN)architecture can improve performance by 1.6%,1.4%,and 2.4%,*** experiments demonstrated that our proposed multi-scale and point selection strategy optimizes the feature extraction capability for overlapping small *** results indicate that the proposed Mask2FusionNet model can perform the shoot segmentation in unstructured environments,realizing the individual distinction of tea shoots,and complete extraction of the shoot edge contours with a segmentation accuracy of 82.0%.The research results can provide algorithmic support for the segmentation and intelligent harvesting of premium tea shoots at different scales.

关键词： Tea shoots attention mechanism multi-scale feature extraction instance segmentation deep learning

Differential bonding behaviors of sodium/potassium-ion storage in sawdust waste carbon derivatives

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Chinese Chemical Letters 2024年第4期35卷 496-501页

作者： Jun-Ming Cao Kai-Yang Zhang jia-lin Yang Zhen-Yi Gu Xing-Long Wu MOE Key Laboratory for UV Light-Emitting Materials and Technology Northeast Normal UniversityChangchun 130024China Department of Chemistry Northeast Normal UniversityChangchun 130024China

Sodium-ion batteries(SIBs) and potassium-ion batteries(PIBs) are the most promising alternatives to lithium-ion batteries, and thus have drawn intensive research attention. Porous carbon materials from different precursors have been widely used as anode materials owing to their compatible storage effectiveness of both larger radii sodium and potassium ions. However, the differential bonding behaviors of Na and K ions with porous carbon-based anode are the significant one worth investigating, which could provide a clean picture of alkali ions storage mechanism. Therefore, in this work, we prepare a porous carbon network derived from sawdust(SDC) wastes, to further analyze the differences on sodium and potassium ions storage behaviors in terms of bond-forming process. It is found that, as-prepared SDC anodes could deliver stable sodium and potassium storage capacities, however, there are notable distinctions in terms of electrochemical behaviors and diffusion processes. By virtue of ex-situ XRD and Raman spectroscopy, the phase transition reaction of potassium ions could be well-observed, and the results shows that the multiple intercalated compounds was formed in SDC network during ions insertion, further resulting in slower diffusion kinetics and larger resistance compared to non-bonded process of sodium ions storage. This study provides more insights into the differences between sodium and potassium ions storage, as well as the energy storage mechanism of porous carbon as anodes for secondary batteries.

关键词： Porous carbon Sodium-ion storage Potassium-ion storage Bonding behaviors Batteries

A self-cleaning window for high-efficiency photodegradation of indoor formaldehyde

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Chinese Chemical Letters 2024年第9期35卷 340-345页

作者： Changzhu Huang Wei Dai Shimao Deng Yixin Tian Xiaolin Liu jia lin Hong Chen Department of Physics Shanghai Key Laboratory of Materials Protection and Advanced Materials in Electric PowerShanghai University of Electric PowerShanghai 200090China Shenzhen Key Laboratory of Interfacial Science and Engineering of Materials State Environmental Protection Key Laboratory of Integrated Surface Water-Groundwater Pollution ControlGuangdong Provincial Key Laboratory of Soil and Groundwater Pollution ControlSchool of Environmental Science and EngineeringSouthern University of Science and TechnologyShenzhen 518055China Eastern Institute for Advanced Study Eastern Institute of TechnologyNingbo 315200China

Formaldehyde(HCHO)as an indoor air pollutant released by new furniture and decorative materials is of great *** a self-cleaning device to remove HCHO is an ideal way to improve indoor air *** this study,a self-cleaning window with a multilayered structure constructed from fluorinedoped tin oxide/bismuth tungstate/resorcinol-formaldehyde resin(FTO/Bi_(2)WO_(6)/RF)has been fabricated,which is capable of degrading HCHO in natural indoor *** as-fabricated device could utilize the natural room light and promote the generation and transfer of the photocatalytic carriers in Bi_(2)WO_(6),which subsequently delivers a good catalytic oxygen reduction efficiency in RF to produce hydrogen peroxide(H_(2)O_(2)).The as-synthesized H_(2)O_(2)could further split into hydroxyl radicals(•OH),then oxide the HCHO molecules in the *** present study demonstrates a novel and efficient strategy to fabricate a transparent multifunctional window for self-cleaning indoor gaseous pollutants,the concept is of great importance to be expanded in a broad range of indoor furniture for in-house air pollution control.

关键词： Bismuth tungstate Resorcinol-formaldehyde Photocatalysis Hydrogen peroxide HCHO degradation