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Science China(Technological Sciences) 2016年第11期59卷 1656-1665页

作者： xiao GangFeng xia Qinxiang CHENG XiuQua LONG Hu School of Mechanical and Automotive Engineering South China University of Technology Department of Aircraft Maintenance Engineering Guangzhou Civil Aviation College Department of Mechanical Engineering The University of Sheffield

A new spinning method to manufacture the cylindrical parts with nano/ultrafine grained structures is proposed, which consists of quenching, power spinning and recrystallization annealing. The microstructural evolution during the different process stages and macroforming quality of the spun parts made of ASTM 1020 steel are investigated. The results show that the microstructures of the ferrites and pearlites in the ASTM 1020 steel are transformed to the lath martensites after quenching. The martensite laths obtained by quenching are refined to 87 nm and a small amount of nanoscale deformation twins with an average thickness of 20 nm is generated after performing a 3-pass stagger spinning with 55% thinning ratio of wall thickness, where the equivalent strain required is only 0.92. The equiaxial ferritic grains with an average size of 160 nm and nano-carbides are generated by subsequent recrystallization annealing at 480°C for 30 min. The spun parts with high dimensional precision and low surface roughness are obtained by the forming method developed in this work, combining quenching with 3-pass stagger spinning and recrystallization annealing.

关键词： nano/ultrafine grained structure cylindrical parts quenching power spinning recrystallization annealing small plastic strain

Autophagy in plants: Physiological roles and post-translational regulation

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Journal of Integrative Plant Biology 2021年第1期63卷 161-179页

作者： Hua Qi Fan-Nv xia Shi xiao State Key Laboratory of Biocontrol Guangdong Provincial Key Laboratory of Plant ResourcesSchool of Life SciencesSun Yat-sen UniversityGuangzhou 510275China

In eukaryotes, autophagy helps maintain cellular homeostasis by degrading and recycling cytoplasmic materials via a tightly regulated *** the past few decades, significant progress has been made towards understanding the physiological functions and molecular regulation of autophagy in plant cells. Increasing evidence indicates that autophagy is essential for plant responses to several developmental and environmental cues, functioning in diverse processes such as senescence, male fertility, root meristem maintenance, responses to nutrient starvation,and biotic and abiotic stress. Recent studies have demonstrated that, similar to nonplant systems,the modulation of core proteins in the plant autophagy machinery by posttranslational modifications such as phosphorylation, ubiquitination,lipidation, S-sulfhydration, S-nitrosylation, and acetylation is widely involved in the initiation and progression of autophagy. Here, we provide an overview of the physiological roles and posttranslational regulation of autophagy in plants.

关键词： autophagy physiological roles post-translational regulation

Coordinated Planning for Fast Charging Stations and Distribution Networks Based on an Improved Flow Capture Location Model

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CSEE Journal of Power and Energy Systems 2023年第4期9卷 1505-1516页

作者： Shiqu xiao xia lei Tao Huang xiang Wang School of Electrical Engineering and Electronic Information Xihua UniversityChengdu 610039China. Department Ingegneria Elettrica Politecnico Di TorinoTorino 10129Italy

The increasing penetration of plug-in electric vehi-cles(PEVs)should lead to a significant reduction in greenhouse gas ***,the development of PEVs is limited by the lack of charging facilities,which is constrained by the coupled transportation-distribution *** paper presents a stochastic bi-level model for the optimal allocation of fast charging stations(FCSs)and distribution network expansion planning(DNEP).First,a sequential capacitated flow-capturing location-allocation model(SCFCLM)is proposed at the lower level to optimize the allocation of FCSs on the transportation ***-Carlo simulation(MCS)is utilized to estimate daily charging load ***,we propose an economic model for DNEP at the upper level,and the chance constrained method is employed to relax power flow constraints to address the uncertainties of *** experiments are conducted to illustrate the proposed planning *** influences of the flow capturing sequence and relaxed confidence level on the PEV charging load,FCS planning strategies and DNEP schemes are *** Terms-Coordinated planning,fast charging station,flow-capturing model,plug-in electric vehicle,stochastic bi-level model.

关键词： Coordinated planning fast charging station flow-capturing model plug-in electric vehicle stochastic bi-level model.

Harmonic Transfer Function Based Single-input Single-output Impedance Modeling of LCC-HVDC Systems

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Journal of Modern Power Systems and Clean Energy 2024年第4期12卷 1327-1332页

作者： Yang Wang Fei xia Ying Wang xianyong xiao College of Electrical Engineering Sichuan UniversityChengdu 610065China

This study presents a harmonic transfer function(HTF)based single-input single-output(SISO)impedance modeling *** method converts an HTF from phase domain to sequence domain and then transforms it into an SISO impedance while preserving the frequency coupling information of different sequences and different *** of this method to a line-commutated converter based high-voltage direct current(LCC-HVDC)system are *** results demonstrate the accuracy of the derived SISO impedance,and a truncation-order selection is *** case study shows that the proposed method facilitates simpler impedance measurements and associated stability analysis.

关键词： Line-commutated converter based high-voltage direct current(LCC-HVDC) harmonic transfer function(HTF) single-input single-output(SISO)impedance frequency coupling

Enantioselective Intramolecular Desymmetric ct-Addition of Cyclohexa- none to Propiolamide Catalyzed by Sodium L-Prolinate

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Chinese Journal of Chemistry 2019年第1期37卷 63-70页

作者： Bao-le Li Wei-Yang Gao Han Li Shuo-qing Zhang xiao-qing Han Jun Lu Ren-xiao Liang Xin Hong Yi-xia Jia College of Chemical Engineering State Key Laboratory Breeding Base of Green-Chemical Synthesis TechnologyZhejiang University of TechnologyHangzhouZhejiang 310014China Department of Chemistry Zhejiang UniversityHangzhouZhejiang 310027China Shanghai Key Laboratory for Molecular Engineering of Chlral Drugs Shanghai Jiao Tong University800 Dongchuan RoadShanghai 200240China

Summary of main observation and conclusion An enantioselective desymmetric nucleophilic α-addition of cyclohexanone to propiolamide has been developed through a 6-exo-dig cyclization *** employing simple and readily available L-proline sodium salt as a bifunctional catalyst,a series of chiral 6,6-bicyclic bridged products bearing morphan scaffold have been isolated in good yields and excellent *** functional theory (DFT)calculations elucidated the origins of the enantioselectivity and regioselectivity of this transformation.A salt bridge that links the amide carbonyl group with proline carboxylate in the transition state was proven to be the driving force for the induction of excellent enantioselectivity.

关键词： enantioselective scaffold group

Roles of membrane and organic fouling layers on the removal of endocrine disrupting chemicals in microfiltration

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Journal of Environmental Sciences 2018年第10期30卷 176-184页

作者： Wenchao Xue Kang xiao Peng Liang xia Huang State Key Joint Laboratory of Environmental Simulation and Pollution Control School of Environment Tsinghua University Department of Environmental Engineering Faculty of Engineering Chulalongkorn University College of Resources and Environment University of Chinese Academy of Sciences

To understand the adsorption behavior of endocrine disrupting chemicals（EDCs） is important for enhancing the treatment performance and preventing potential secondary pollution caused by EDCs desorption in a microfiltration system. The dynamic adsorption of four representative EDCs, namely estriol（E3）, 17β-estradiol（E2）, 17α-ethynylestradiol（EE2）, and 4-nonylphenol（4-NP） in a microfiltration system was investigated using the Thomas＇ *** product of the equilibrium constant and the total adsorption capacity of the membrane,Ka, for E3, E2, EE2, and 4-NP were 4.91, 9.78, 15.6, and 826, respectively, strongly correlating with the compound octanol–water partition coefficient（KOW）. Adsorption appeared to be enhanced when organic fouling formed on the surface of membrane, indicating the role of an additional adsorption column for EDCs acted by a fouling layer in microfiltration. Results of a comparison between the Ka values for clean membrane and fouled membrane illustrated that the significant contribution made by fouling layers may be attributed to the foulant layer＇s hydrophobicity（in the case of calcium humate layer） and thickness（in the case of calcium alginate layer）. This study provided a novel perspective to quantitatively analyze the dynamic adsorption behavior of trace pollutants in membrane process.

关键词： Endocrine disrupting chemicals Microfiltration membrane Dynamic adsorption Thomas' model Organic membrane fouling

Synthesis and electrochemical properties of 2,6-bis(6-aryl-[1,2,4]- triazolo[3,4-b][1,3,4]-thiadiazole-3-yl)pyridines

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Chinese Chemical letters 2007年第5期18卷 505-508页

作者： Chun xia Tan Ruo Fei Feng xiao xia Peng The College of Traditional Medicine of Gansu Lanzhou 730030 China Life Science ＆ Engineering College Northwest University for Nationalities Lanzhou 730030 China

By the condensation of 2,6-bis（4-amino-5-mercapto-[1,2,4]-triazoles-2）pyridine with aromatic acid in the presence of phosphorus oxychloride. Compounds of 2,6-bis（6-aryl-[1,2,4]-triazolo[3,4-b][1,3,4]-thiadiazole-3-yl）pyridines were synthesized. Their structures were confirmed by IR, ^1H NMR spectroscopies and elemental analysis. Their electrochemical behavior and cyclic voltammogram also were be studied. The results showed that they have high ionization potentials and good affinity.

关键词： Synthesis Triazolo-thiadiazoles Electrochemical properties

Vertical dynamic response of the ballastless track on long-span plate-truss cable-stayed bridges

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Science China(Technological Sciences) 2015年第2期58卷 236-247页

作者： LI Yong le SU Yang xia Fei Long ZHANG Nan Department of Bridge Engineering Southwest Jiaotong University MOE Key Laboratory of High Speed Railway Engineering Southwest Jiaotong University Department of Bridge Engineering Northern Jiaotong University

An analytical model is presented to study vertical dynamic response of the ballastless track on long-span plate-truss cable-stayed bridges based on an explicit dynamic analysis *** the model,the train,ballastless track and bridge are treated as a coupled vibration system with *** simulating the dynamic process of the system,this paper discusses the distribution law of dynamic responses of the bridge deck and the bed *** shows the necessity of a base plate for the ballastless track on the long-span plate-truss cable-stayed *** of the influence of different train speeds and stiffness of the elastic vibration-damping pad on the dynamic responses of the bridge deck and the bed slab is also *** reasonable stiffness value of elastic vibration-damping pad is proposed.

关键词： long-span cable-stayed bridge plate-truss girder ballastless track train-induced vibration vehicle-bridge system

Visual field mean deviation and relevant factors in 928 Chinese retinitis pigmentosa patients

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International Journal of Ophthalmology(English edition) 2018年第12期11卷 1978-1983页

作者： Hui Ye xiao-Ping xia Department of Ophthalmology the Third Affiliated Hospital of Sun Yat-sen University

AIM: To investigate the associations between demographic and clinical factors with the rate of visual field mean derivation(MD) decline in retinitis pigmentosa(RP) ***: Correlations of MDs with the visual acuity and retinal pigmentation were analyzed in 928 RP patients. MD decreasing rate in 10 y and potential influences of gender, age, family history and retinal pigmentation on the rate were explored in 201 RP patients. RESULTS: In the 928 patients, average MD and visual acuity were-14.44±8.61 dB and 0.79±0.35 respectively and when MD was lower than-9.18 dB the visual acuity would be below 1.0(20/20). The average MD medium between eyes with or without retinal pigmentation was-14.82 dB. In 123 non-pigmented eyes, the average MD were lower than the medium but in 153 pigmented eyes it was higher than that. In the 201 patients, the average decreasing value of MD in 10 years’ period was-8.01±3.66 dB and the value were correlated to retinal pigmentation but not to gender, age or RP family history. CONCLUSION: The rate of MD decline in RP eyes is significantly related to retinal pigmentation. Our study demonstrates the quantitative rate of MD decline in RP patients and the value of MD could well reflect the severity of RP.

关键词： retinitis pigmentosa mean deviation of visual field visual acuity retinal pigmentation

Intestinal microecology-based treatment for inflammatory bowel disease:Progress and prospects

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World Journal of Clinical Cases 2023年第1期11卷 47-56页

作者： xia-xiao Yan Dong Wu Department of Gastroenterology State Key Laboratory of Complex Severe and Rare DiseasesPeking Union Medical College HospitalChinese Academy of Medical SciencesPeking Union Medical CollegeBeijing 100730China

Inflammatory bowel disease(IBD)is a chronic,recurrent,and debilitating disorder,and includes Crohn’s disease and ulcerative *** pathogenesis of IBD is closely associated with intestinal dysbiosis,but has not yet been fully *** and environmental factors can influence IBD patients’gut microbiota and metabolism,disrupt intestinal barriers,and trigger abnormal immune *** have reported the alteration of gut microbiota and metabolites in IBD,providing the basis for potential therapeutic *** microbiota-based treatments such as pre/probiotics,metabolite supplementation,and fecal microbiota transplantation have been extensively studied,but their clinical efficacy remains *** the intestinal barrier and promoting mucosal healing have also been *** here review the current clinical trials on intestinal microecology and discuss the prospect of research and practice in this field.

关键词： Inflammatory bowel disease Probiotics Prebiotics Intestinal metabolites Fecal microbiota transplantation Intestinal barrier