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Journal of Iron and Steel Research(International) 2022年第1期29卷 124-131页

作者： Dong-bin Jiang Li-feng Zhang Ya-dong Wang School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China State Key Lab of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao 066004HebeiChina

The effect of mold electromagnetic stirring(M-EMS)on the solidification structure and solute segregation in the continuous casting bloom of U78CrV steel is investigated.The solute distribution in the macroscale is analyzed using a carbon–sulfur analyzer and that in the microscale is measured with an electron probe microanalyzer.The Image-J software is applied to analyze the number density and area ratio of segregation spots.The results show that the segregation spots are mainly located in the columnar to equiaxed transition zone and the equiaxed zone,which are enriched with C,Cr,and Mn elements.With the M-EMS applied,the columnar grain inclines to the upstream side.As the current intensity increases,the deflecting angle of columnar grain rises,especially with the current intensity larger than 300 A.Besides,the center segregation shows a declining trend and the area fraction of the equiaxed zone rises clearly.Moreover,it is found that the area ratio and number density of segregation spots increase with the higher current intensity of M-EMS.

关键词： Solidification structure Macrosegregation Mesosegregation Segregation spot Mold electromagnetic stirring

Treating Chronic Diseases by Regulating the Gut Microbiota

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Engineering 2022年第11期18卷 17-20页

作者： bin Hong Jian-dong jiang NHC Key Laboratory of Biotechnology of Antibiotics Institute of Medicinal BiotechnologyChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100050China CAMS Key Laboratory of Synthetic Biology for Drug Innovation Institute of Medicinal BiotechnologyChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100050China

Chronic diseases comprise a wide range of abnormal conditions and illnesses that impair patients’physical and/or mental functioning,and last for a long time.Largely a contemporary plague,chronic diseases are responsi... 详细信息

关键词： diseases Chronic mortality

Effect of feeding parameters on ingot segregation and shrinkage pore in vacuum arc remelting

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Journal of Iron and Steel Research(International) 2023年第6期30卷 1268-1278页

作者： Dong-bin Jiang Fu-zhong Yang Jian Zhang Yang Zhou Li-feng Zhang School of Metallurgy and Ecological Engineering University of Science and Technology BeijingBeijing 100083China Chengdu Advanced Metal Materials Industrial Technology Institute Chengdu 610303SichuanChina School of Mechanical and Materials Engineering North China University of TechnologyBeijing 100144China

The feeding parameters in the final stage of vacuum arc remelting process obviously affect the solute segregation and shrinkage pore depth.Coupled with the electromagnetic field,fluid flow,and solute transport,a numerical model was built to investigate the effect of feeding parameters on the ingot solidification phenomena.The Nb segregation and shrinkage pore depth in the solidified ingot were measured.The results show that the liquid moves along the solidification front and the vertex flow is formed in the liquid pool,which promotes solute transport.In the solidified ingot,the Nb segregation in the lower part is negative,while that in the upper part is positive.With the differential electrode applied,the positive segregation is slightly reduced but the segregation distribution remains unchanged.As the feeding current decreases,the positive segregation zone moves toward the ingot top surface,due to the final solidification position moving upward.With the feeding time extended,the positive segregation moves to the top surface and the shrinkage pore depth is reduced.As the feeding time is set at 12 min,the shrinkage pore depth can be reduced to 21 mm.

关键词： Vacuum arc remelting Feeding parameter Macrosegregation Shrinkage pore Solidification

Fault-tolerant control and vibration suppression of flexible spacecraft: An interconnected system approach

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Chinese Journal of Aeronautics 2020年第7期33卷 2014-2023页

作者： Qian LI Hao YANG dong ZHAO bin jiang College of Automation Engineering Nanjing University of Aeronautics and AstronauticsNanjing 211106China

This paper considers a fault-tolerant control and vibration suppression problem of flexible spacecraft.The attitude dynamics is modeled by an interconnected system,in which the rigid part and the flexible part are coupled with each other.Such a model allows us to use the interconnected system approach to analyze the flexible spacecraft.Both distributed and decentralized observer-based fault-tolerant control schemes are developed,under which the closed-loop stability of flexible spacecraft can be ensured by using the cycle-small-gain theorem.Compared with the traditional method,this paper considers the faults occurred not only in the rigid parts,but also in the flexible parts.In addition,the application of the interconnected system approach simplifies the system model of flexible spacecraft,thereby the difficulty of theoretical analysis and engineering practice of fault-tolerant control of flexible spacecraft are greatly reduced.Simulation results show the effectiveness of the proposed methods and the comparison of different fault-tolerant control approach.

关键词： Cycle-small-gain theorem Decentralized fault-tolerant control Distributed fault-tolerant control Flexible spacecraft Interconnected system

Nutritional status and prognostic factors for mortality in patients admitted to emergency department observation units:a national multi-center study in China

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世界急诊医学杂志(英文) 2023年第1期14卷 17-24页

作者： Hai-jiang Zhou dong-jing Zuo Da Zhang Xin-hua He Shu-bin Guo Nutrition School of Education College of Chinese Emergency Medicine Beijing Key Laboratory of Cardio-pulmonary Cerebral ResuscitationEmergency Medicine Clinical Research CenterBeijing Chao-yang HospitalCapital Medical UniversityBeijing 100020China

BACKGROUND:Nutritional risk is common among patients admitted to the emergency department and is associated with adverse clinical outcomes.Despite its large population,few comprehensive studies have been conducted in China concerning the nutritional status of patients admitted to emergency department observation units(EDOUs).METHODS:Patients admitted to EDOUs of 90 tertiary hospitals in China between June 2020 and December 2020 were enrolled.Demographic information,laboratory parameters,nutritional support therapies,and 28-day mortality were recorded.Risk factors for mortality were examined using multi-variateadjusted logistic regression analysis.Receiver operating characteristic(ROC)curves for each predictor of mortality were plotted,and the area under the ROC(AUROC)curves was compared.RESULTS:A total of 2,005 eligible patients were finally enrolled.At the 28-day follow-up,1,911 patients survived,and 94 died.The group with a Nutritional Risk Screening 2002(NRS 2002)score of 3-4 points was the largest(52.01%).The number of patients receiving oral nutritional supplements,enteral nutrition(EN),parenteral nutrition(PN),and the combination of EN and PN was 425,314,853,and 413,respectively.Among the total,77.55%of patients had nutritional risk(NRS 2002≥3).The proportion of patients with high nutritional risk(NRS2002≥5)in the age group>80 years was significantly higher than that in the age group 66-80 years(29.00%vs.23.93%,P=0.032),but not significantly higher than that in the age group 18-65 years(29.00%vs.26.54%,P=0.449).Logistic regression analysis revealed that heart failure(odds ratio[OR]1.856,95%confidence interval[CI]1.087-3.167,P=0.023),consciousness(OR 2.967,95%CI 1.894-4.648,P<0.001),Acute Physiology and Chronic Health Evaluation II(APACHE II)score(OR 1.037,95%CI 1.017-1.058,P<0.001),NRS 2002 score(OR 1.286,95%CI 1.115-1.483,P=0.001),and Mini Nutritional Assessment-Short Form score(OR 0.946,95%CI 0.898-0.997,P=0.039)were all independent risk factors for 28-day mortality.APACHE II and NRS 2002 scores were supe

关键词： Nutritional risk Malnutrition Nutritional Risk Screening 2002 Mini Nutritional Assessment-Short Form

Current progress of research on heat -resistant Mg alloys: A review

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International Journal of Minerals,Metallurgy and Materials 2024年第6期31卷 1406-1425页

作者： Hong Yang Wenlong Xie jiangfeng Song Zhihua dong Yuyang Gao bin jiang Fusheng Pan National Engineering Research Center for Magnesium Alloys Chongqing UniversityChongqing 400044China College of Materials Science and Engineering Chongqing UniversityChongqing 400044China

With the increasing attention received by lightweight metals,numerous essential fields have increased requirements for mag-nesium(Mg)alloys with good room-temperature and high-temperature mechanical properties.However,the high-temperature mechanic-al properties of commonly used commercial Mg alloys,such as AZ91D,deteriorate considerably with increasing temperatures.Over the past several decades,extensive efforts have been devoted to developing heat-resistant Mg alloys.These approaches either inhibit the gen-eration of thermally unstable phases or promote the formation of thermally stable precipitates/phases in matrices through solid solution or precipitation strengthening.In this review,numerous studies are systematically introduced and discussed.Different alloy systems,includ-ing those based on Mg–Al,Mg–Zn,and Mg–rare earth,are carefully classified and compared to reveal their mechanical properties and strengthening mechanisms.The emphasis,limitations,and future prospects of these heat-resistant Mg alloys are also pointed out and dis-cussed to develop heat-resistant Mg alloys and broaden their potential application areas in the future.

关键词： magnesium alloys mechanical properties heat resistance microstructures high temperatures strengthening mechanisms

Grain refinement of Mg-3Y alloy using Mg-10Al_(2)Y master alloy

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Journal of Rare Earths 2021年第7期39卷 881-888,I0005页

作者： Zhongtao jiang Xiang Meng bin jiang Shan jiang Jiahong Dai Jingren dong Yongfeng Ding Chongqing Key Laboratory of Materials Surface&Interface Science Chongqing University of Arts and SciencesChongqing 402160China College of Materials Science and Engineering National Engineering Research Center for Magnesium AlloysChongqing UniversityChongqing 400044China Chongqing Academy of Science and Technology Chongqing 401123China College of Mechanical and Electrical Engineering Yangtze Normal UniversityChongqing 408100China

The as-extruded Mg-10Al_(2)Y master alloy was chosen as a novel grain refiner for as-cast Mg-3Y alloy.Contrast samples of cast Mg-3Y alloy added with pure Al and Mg-Zr master alloy grain refiners were prepared under the same conditions.In this study,the influence of addition amounts of Al_(2)Y and holding time on grain refinement efficiency as well as tensile properties was investigated.And the grain refining ability of the Al_(2)Y particles was systematically evaluated in terms of the addition amounts,number density of the Al_(2)Y particles and holding time.The finest grains are achieved at 2 wt% Al_(2)Y addition amount,which corresponds to number density of the polygonal Al_(2)Y particles of 420-460 mm^(-2).The Mg-10Al_(2)Y master alloy has significant refinement performance and no refining recession occurs at the holding time within 60 min,or the settling time up to 180 min.Grain refinement and the second phase strengthening of uniformly distributed Al_(2)Y particles contribute to the simultaneous enhancement on both strength and elongation of Mg-3Y alloy.

关键词： Grain refinement Al_(2)Y Mg-Y alloys Microstructure Rare earths

Iron adsorption engineering facilitated by Cu doping on cobalt hydroxide host with enhanced oxygen evolution reaction

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Nano Research 2023年第2期16卷 2111-2118页

作者： Xinyu Zhang Yiwen dong Huiying Wang Ziyi Zhao Wenchun jiang bin dong Han Hu Chenguang Liu Yongming Chai State Key Laboratory of Heavy Oil Processing College of Chemistry and Chemical EngineeringChina University of Petroleum(East China)Qingdao 266580China College of New Energy China University of Petroleum(East China)Qingdao 266580China

Iron plays a crucial role in improving the oxygen evolution reaction(OER)activity of hydroxide materials.Increasing the number of iron active sites at the solid–liquid interface is beneficial to enhancing the OER performance of catalysts but still challenging.Here,by systematic exploring the activity trends of M(OH)_(x)and Cu-M(OH)_(x)(M=Mn,Cu,Ni,Fe,and Co),we discover that the Cu doping can promote the deposition of Fe active sites on metal hydroxide and Cu-Co(OH)2 shows the most favorable iron adsorption capacity.When loaded on a conductive substrate(cobalt foam(CF),the M-Cu-Co(OH)2/CF(Co(OH)_(2))prepared by molten salt method)exhibits an attractive low overpotential of 337 mV at 1,000 mA·cm^(−2).Using in anion exchange membrane(AEM)water electrolyzer,the single cell with M-Cu-Co(OH)_(2)/CF as anode catalyst performs a stable cell voltage of 2.02 V to reach 1,000 mA·cm^(−2)over 24 h,indicating a great application potential for actual electrolytic water.Therefore,the promoted adsorption of copper on iron provides a new perspective for further enhancing the OER activity of other metal hydroxides.

关键词： copper doping promoted Fe adsorption industrial-level current density anion exchange membrane water electrolyzer oxygen evolution reaction

Mesenteric adipose tissue B lymphocytes promote intestinal injury in severe acute pancreatitis by mediating enteric pyroptosis

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Hepatobiliary & Pancreatic Diseases International 2024年第3期23卷 300-309页

作者： Qing Huang Jia-Wen Liu Hai-bin dong Zheng-Jie Wei Jin-Zhe Liu Yu-Tang Ren Xuan jiang Bo jiang Department of Gastroenterology Beijing Tsinghua Changgung HospitalSchool of Clinical MedicineTsinghua UniversityBeijing 102218China

Background:Visceral adipose tissue(VAT)has been linked to the severe acute pancreatitis(SAP)prognosis,although the underlying mechanism remains unclear.It has been reported that pyroptosis worsens SAP.The present study aimed to verify whether mesenteric adipose tissue(MAT,a component of VAT)can cause secondary intestinal injury through the pyroptotic pathway.Methods:Thirty-six male Sprague Dawley(SD)rats were divided into six different groups.Twelve rats were randomly divided into the SAP and control groups.We monitored the changes of MAT and B lymphocytes infiltration in MAT of SAP rats.Twelve SAP rats were injected with MAT B lymphocytes or phosphate buffer solution(PBS).The remaining twelve SAP rats were first injected with MAT B lymphocytes,and then with MCC950(NLRP3 inhibitor)or PBS.We collected blood and tissue samples from pancreas,gut and MAT for analysis.Results:Compared to the control rats,the SAP group showed inflammation in MAT,including higher expression of tumor necrosis factor(TNF-α)and interleukin-6(IL-6),lower expression of IL-10,and histological changes.Flow cytometry analysis revealed B lymphocytes infiltration in MAT but not T lymphocytes and macrophages.The SAP rats also exhibited intestinal injury,characterized by lower expression of zonula occludens-1(ZO-1)and occludin,higher levels of lipopolysaccharide and diamine oxidase,and pathological changes.The expression of NLRP3 and n-GSDMD,which are responsible for pyroptosis,was increased in the intestine of SAP rats.The injection of MAT B lymphocytes into SAP rats exacerbated the inflammation in MAT.The upregulation of pyroptosis reduced tight junction in the intestine,which contributed to the SAP progression,including higher inflammatory indicators and worse histological changes.The administration of MCC950 to SAP+MAT B rats downregulated pyroptosis,which subsequently improved the intestinal barrier and ameliorated inflammatory response of SAP.Conclusions:In SAP,MAT B lymphocytes aggravated local inflammation,and promoted the injury to the int

关键词： Acute pancreatitis Mesenteric adipose tissue B lymphocyte Intestinal barrier Pyroptosis

Demethylenetetrahydroberberine protects dopaminergic neurons in a mouse model of Parkinson's disease

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Chinese Journal of Natural Medicines 2022年第2期20卷 111-119页

作者： WEN Jing ZHANG Yuan-Qiang LIU dong-Qing YAO Xu-Tao jiang Hua ZHANG Yu-bin Department of Biochemistry School of Life Science and TechnologyChina Pharmaceutical UniversityNanjing 211198China

Parkinson’s disease(PD)is a multifactorial disorder of the nervous system where a progressive loss of dopaminergic neurons exist.However,the pathogenesis of PD remains undefined,which becomes the main limitation for the development of clinical PD treatment.Demethylenetetrahydroberberine(DMTHB)is a novel derivative of natural product berberine.This study was aimed to explore the neuroprotective effects and pharmacological mechanism of DMTHB on Parkinson’s disease using C57BL/6 mice.A PD model of mice was induced by administration of MPTP(20 mg·kg^(-1))and probenecid(200 mg·kg^(-1))twice per week for five weeks.The mice were administered with DMTHB daily by gavage at the dose of 5 and 50 mg·kg^(-1)for one-week prophylactic treatment and five-week theraputic treatment.The therapeutic effects of DMTHB were evaluated by behavior tests(the open field,rotarod and pole tests),immunohistochemical staining of tyrosine hydroxylase(TH),Nissl staining and biochemical assays.The molecular mechanisms of DMTHB on the key biomarkers of PD pathological states were analyzed by Western blot(WB)and qRT-PCR.DMTHB treatment alleviated the behavioral disorder induced by MPTP-probenecid.Nissl staining and TH staining showed that the damage of dopaminergic neurons in the substantia nigra was remarkably suppressed by DMTHB treatment.Western blot results showed that the ratio of Bcl-2/Bax and TH increased,but the level ofα-synuclein(α-syn)was remarkably reduced,which indicated that the apoptosis of dopaminergic neurons in mice was significantly reduced.The protein phosphorylation of p-PI3K,p-AKT and p-mTOR also increased about 2-fold,compared with the model group.Furthermore,qRT-PCR results demonstrated that the mRNA levels of pro-inflammatory cytokines,IL-1βand TNF-α,were reduced,but the level of anti-inflammatory cytokine IL-10 increased after DMTHB treatment.Finally,the cellular assay displayed that DMTHB was also a strong antioxidant to protect neuron cell line PC12 by scavenging ROS.In this study,we demonstrated DMTHB alleviates the be

关键词： Demethylenetetrahydroberberine Parkinson's disease Dopaminergic neurons Apoptosis Neuroinflammation