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Achieving strength-ductility synergy in a non-equiatomic Cr_(10)Co_(30)Fe_(30)Ni_(30)high-entropy alloy with heterogeneous grain structures

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Rare Metals 2022年第8期41卷 2864-2876页

作者： chen-Liang Chu wei-ping chen Jun-chen Liu Qiang chen Zhi-Qiang Fu Guangdong Key Laboratory for Advanced Metallic Materials Processing South China University of TechnologyGuangzhou510641China Southwest Technology and Engineering Research Institute Chongqing400039China

Cold rolling and post-deformation annealing(PDA)heat treatments were used to produce heterogeneous grain structures(HGS)in a single-phase face-centered cubic(fcc)Cr_(10)Co_(30)Fe_(30)Ni_(30)high-entropy alloy(HEA).The microstructural evolution and microstructure-property relationship of the HEA were systematically studied under different *** could be achieved in PDA-treated samples at 875℃for 20 s and at 900℃for 20 s(PDA-900-20 s).PDA-900-20 s sample exhibits the most excellent combination of strength and ductility,showing a tensile yield strength of~590 MPa,an ultimate strength of~706 MPa and a total elongation of~23.9%.Additionally,compared with the homogenized counterpart exhibiting homogenous grains,PDA-900-20 s sample displays a notable increment of~413%in yield strength and simultaneously maintains a good *** dominated strengthening mechanisms in PDA-900-20 s sample are grain-boundary strengthening and heterogeneous deformation-induced(HDI)strengthening,whereas the good ductility is mainly resulted from the HDI ***,the present study provides an effective and simple pathway to overcome the strength-ductility tradeoff of typical fcc HEAs through heterogeneous microstructure.

关键词： High-entropy alloy Heterogeneous grain structures Hetero-deformation-induced hardening Mechanical properties Strengthening mechanism

Privacy-Preserving Consensus-Based Distributed Economic Dispatch of Smart Grids via State Decomposition

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IEEE/CAA Journal of Automatica Sinica 2024年第5期11卷 1250-1261页

作者： wei chen Guo-ping Liu The authors are with the Center for Control Science and Technology Southern University of Science and TechnologyShenzhen 518055China

This paper studies the privacy-preserving distributed economic dispatch(DED)problem of smart *** autonomous consensus-based algorithm is developed via local data exchange with neighboring nodes,which covers both the islanded mode and the grid-connected mode of smart *** prevent power-sensitive information from being disclosed,a privacy-preserving mechanism is integrated into the proposed DED algorithm by randomly decomposing the state into two parts,where only partial data is *** objective is to develop a privacy-preserving DED algorithm to achieve optimal power dispatch with the lowest generation cost under physical constraints while preventing sensitive information from being *** this end,a comprehensive analysis framework is established to ensure that the proposed algorithm can converge to the optimal solution of the concerned optimization problem by means of the consensus theory and the eigenvalue perturbation *** particular,the proposed autonomous algorithm can achieve a smooth transition between the islanded mode and the grid-connected ***,rigorous analysis is given to show privacy-preserving performance against internal and external ***,case studies illustrate the feasibility and validity of the developed algorithm.

关键词： preserving autonomous mode

揭示明确定义的金属-N_(4)位点在电催化硝酸盐还原中的活性趋势

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Chinese Journal of Catalysis 2024年第4期59卷 195-203页

作者：蒋远杨级李沐霖王雪佳杨娜陈伟平董金超李剑锋厦门大学能源学院固体表面物理化学国家重点实验室化学化工学院厦门大学物理科学与技术学院能源材料化学协同创新中心福建厦门361005 福建能源材料科学与技术创新实验室(嘉庚创新实验室) 福建厦门361005 电子科技大学材料与能源学院四川成都611731

氨是一种重要的化工原材料,广泛用于肥料、药物、塑料以及其它化工产品的生产.特别是,氨作为一种绿色、新型的替代燃料,正逐渐被视为未来可持续能源体系的重要组成部分之一.近期,研究者们提出了一种新的等离子体电催化合成氨的方法,为... 详细信息

氨是一种重要的化工原材料,广泛用于肥料、药物、塑料以及其它化工产品的生产.特别是,氨作为一种绿色、新型的替代燃料,正逐渐被视为未来可持续能源体系的重要组成部分之一.近期,研究者们提出了一种新的等离子体电催化合成氨的方法,为氨的生产开辟了新的途径.该方法首先在等离子处理条件下将空气中的氮气和氧气氧化成为氮氧化物;然后,通过电催化还原NOx-(主要为NO_(2)-/NO3-等)合成氨.在该过程中,金属-氮-碳单原子(M-N-C SACs)催化剂因其金属原子利用率高、活性和选择性好等优点而受到广泛关注.然而,由于当前催化剂合成路线的可控性不足,导致金属中心的配位环境复杂,MNx配位数(x=2-5)不明确,阻碍了对催化剂本征活性趋势的深入揭示.为了解决上述问题,研究者们开始关注具有均匀且明确MN_(4)结构的金属酞菁(MPc),并将其作为模型催化剂,用于深入研究电催化硝酸盐还原反应的活性位点和反应机理.本文将六种具有明确MN_(4)结构的金属酞菁催化剂(M=Mn,Fe,Co,Ni,Cu和Zn)负载在卡博特碳黑XC-72R载体上,并探究了不同金属中心的MN_(4)位点对硝酸盐还原合成氨的活性影响.扫描电子显微镜、X射线光电子能谱以及氮气吸脱附等温曲线结果表明,六种不同金属中心的MPc/XC-72R催化剂间的差异仅在于金属中心,从而排除了载体等其他因素的干扰.实验结果显示,金属中心对硝酸盐还原合成氨的活性顺序为:FeN_(4)>CuN_(4)>NiN_(4)>MnN_(4)>CoN_(4)>ZnN_(4).其中,FeN_(4)位点表现出最好的催化活性,在-1.0 V ***时,氨的法拉第效率达到83.3%,产率为2.94 mgNH3 h^(-1)cm^(-2),转化频率(TOF)为4395.2 h^(-1).相比之下,在相同条件下,ZnN_(4)位点上亚硝酸盐的选择性和产率最高,亚硝酸盐的法拉第效率为49.1%,产率达到16.8 mgNO_(2)h^(-1)cm^(-2).此外,FeN_(4)位点的单原子催化剂表现出较好的循环稳定性,在-0.8 V ***的电位下,经过20次循环测试,氨的法拉第效率仍能维持在80%左右.密度泛函理论计算结果表明,FeN_(4)位点对NO_(2)中间体和氢原子具有适宜的吸附能,有利于硝酸盐加氢进一步生成氨.相比之下,NO_(2)在ZnN_(4)位点上吸附很弱,导致NO_(2)容易从催化剂表面脱附至溶液中,形成亚硝酸盐副产物.此外,计算结果还显示,FeN_(4)位点上硝酸还原反应的决速步骤NO*→HNO*的自由能差仅为0.07 eV,进一步证实了FeN_(4)位点在硝酸盐还原合成氨反应中的优异活性.综上,本文系统研究了六种具有明确MN_(4)结构的金属酞菁催化剂在硝酸盐还原合成氨反应中的活性趋势,并探究了不同MN_(4)位点对硝酸盐还原的活性影响.结合密度泛函理论计算,揭示了不同MN_(4)位点对硝酸盐还原反应的机理.为深刻理解硝酸盐还原反应机制,指导设计高效活性位提供了参考.

关键词：电催化金属酞菁金属-N_(4) 硝酸根还原成氨活性趋势

Corrosion behavior of a spark plasma sintered Fe-2OMn-11Al-1.8C- 5Cr alloy in molten aluminum

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Journal of Iron and Steel Research International 2018年第5期25卷 563-571页

作者： Jian Liu wei-ping chen Xian-man Zhang Zhi-qiang Fu Guangdong Key Laboratory for Advanced Metallic Materials Processing South China University of TechnologyGuangzhou 510640 Guangdong China College of Engineering and Technology Normal College ofZunyi Zunyi 563006 Guizhou China Mechanical and Electrical Engineering College Hainan University Haikou 570228 Hainan China

The corrosion behavior of an Fe-20Mn-11Al-1.8C-5Cr alloy prepared by spark plasma sintering was investigated via immersion tests in molten aluminum at 750℃ for 1 and 4 h, respectively, and a hot work steel （AlSI H13） was included as a reference. The experimental results show that the corrosion rate of Fe-20Mn-11Al-1.8C-5Cr alloy is - 24% of that of H13 steel, suggesting that Fe-20Mn-11Al-1.8C-5Cr alloy in molten aluminum possesses better corrosion resistance than H13 steel. Detailed analysis show that k-carbide （（Fe, Mn）3AlCx） and Cr7C3 carbide precipitated in the matrix play a key role in enhancing the corrosion resistance of Fe-20Mn-11Al-1.8C-5Cr alloy in molten aluminum. Both of them show better corrosion resistance than 7-Fe matrix and H13 steel, and can also take on the role of roots in grasping the corrosion product and restrain them from spalling into the molten aluminum.

关键词： Fe-Mn-Al-C-Cr alloy · Molten aluminum. Immersion · Corrosion behavior

Clinical value of continuous administration of sorafenib in combination with modified transarterial chemoembolization in patients with unresectable hepatocellular carcinoma

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Chinese Medical Journal 2013年第2期126卷 385-386页

作者： HUANG Yong-hui chen wei LI Jia-ping chen Bin YANG Jian-yong Department of Interventional Radiology First Affiliated Hospitalof Sun Yat-sen University Guangzhou Guangdong 510080 China

Hepatocellular carcinoma （HCC） is a major threat to human health in China with high morbidity andmortality. Surgical resection and liver transplantation are the most promising treatments for HCC. The majority of patients, however, are not eligible for surgery due to 1 advanced tumor, multifocal disease or poor liver reserve. Recently, transarterial chemoembolization （TACE） improved survival compared with best supportive care in two individual clinical trials.2 Sorafenib is a multikinase inhibitor that targets both tumor cell proliferation and angiogenesis. The current standard of practice is to treat BCLC stage B HCC with TACE alone and more advanced （BCLC stage C） HCC with sorafenib only.1

关键词： hepatocellular carcinoma, progression-free survival, sorafenib transarterial chemoembolization

Microstructure and mechanical properties of as-cast(CuNi)100-xCox medium-entropy alloys

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China Foundry 2022年第6期19卷 511-518页

作者： Zhi-yong Yang wei-ping chen Liang-yan Hao chen-liang Chu Da-hai Zeng wei Xiong Zhi-qiang Fu Guangdong Key Laboratory for Advanced Metallic Materials Processing South China University of TechnologyGuangzhou 510640China Physical Metallurgy and Materials Design Laboratory Department of Mechanical Engineering and Materials ScienceUniversity of PittsburghPittsburghPA15261USA National Engineering Research Center of Near-net-shape Forming for Metallic Materials South China University of TechnologyGuangzhou 510640China

Microstructure and mechanical properties of non-equiatomic(CuNi)_(100-x)Co_(x)(x=15,20,25 and 30,at.%)medium-entropy alloys(MEAs)prepared by vacuum arc-melting were *** show that all the as-cast MEAs exhibit dual face-centered cubic(fcc)solid-solution phases with identical lattice constant,showing typical dendrite structure consisting of(Ni,Co)-rich phase in dendrites and Cu-rich phase in *** positive enthalpy of mixing among Cu and Ni-Co elements is responsible for the segregation of *** the increase of Co content,the volume fraction of(Ni,Co)-rich phase increases while the Cu-rich phase decreases,resulting in an increment of yield strength and a decrement of elongation for the(CuNi)_(100-x)Co_(x) ***-indentation test results show a great difference of microhardness between the two fcc phases of the *** measured microhardness value of the(Ni,Co)-rich phase is almost twofold as compared to that of the Cu-rich phase in all the(CuNi)_(100-x)Co_(x) *** the deformation of the MEAs,the Cu-rich phase bears the main plastic strain,whereas the(Ni,Co)-rich phase provides more pronounced strengthening.

关键词： medium-entropy alloys microstructure mechanical properties nano-indentation

Noninfectious Fever Following Aortic Surgery:Incidence,Risk Factors,and Outcomes

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Chinese Medical Sciences Journal 2009年第4期24卷 213-219页

作者： Yun-tai Yao Li-huan Li Qian Lei Lei chen wei-peng Wang wei-ping chen Department of Anesthesiology Fuwai Cardiovascular Hospital Chinese Academy of Medical Sciences ＆ Peking Union Medical College Beijing 100037 China

Objective To determine the incidence, course, potential risk factors, and outcomes of noninfectious fever developed in patients after aortic surgery. Methods Patients who received operation for aortic aneurysm or dissection in our center from January 2006 to January 2008 were reviewed. Patients who met one of the following criteria were excluded： having a known source of infection during hospitalization; having a preoperative oral temperature greater than or equal to 38.0℃; undertaking emergency surgery; having incomplete data. Univariate analysis was performed in patients with noninfectious postoperative fever and those without, with respect to demographics, intraoperative data, etc. Risk factors for postoperative fever were considered for the muhivariate logistic regression model if they had a P value less than 0.10 in the univariate analysis. Results Totally 463 patients undergoing aortic surgery were enrolled for full review. Among them, 345 （74.5%） patients had noninfectious postoperative fever, the other 118 （25.5%） patients didn＇t develop postoperative fever. Univariate analysis demonstrated that several risk factors were associated with the development of noninfectious postoperative fever, including weight, surgical procedure, minimum intraoperative bladder temperature, temperature upon intensive care unit （ICU） admission, discharge, and during ICU stay, as well as blood transfusion. In a further multivariate analysis, surgical site of thoracic and thoracoabdominal aorta （odds ratio： 4.861; 95% confidence interval： 3.029-5.801; P=0.004）, lower minimum intraoperative bladder temperature （odds ratio： 1.117; 95% confidence interval： 1.01-1.24; P=0.04）, and higher temperature on admission to the ICU （odds ratio： 2.57; 95% confidence interval： 1.28-5.18; P=0.008） were found to be significant predictors for noninfectious postoperative fever. No difference was found between the febrile and afebrile patients with regard to postoperative hospitalization duration （P

关键词： fever noninfectious aortic surgery

Single-Ni-atoms on nitrogenated humic acid based porous carbon for CO_(2) electroreduction

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Frontiers of Chemical Science and Engineering 2024年第5期18卷 37-47页

作者： Delei Yu Ying chen Yao chen Xiangchun Liu Xianwen wei ping Cui Anhui Key Laboratory of Coal Clean Conversion&Utilization School of Chemistry and Chemical EngineeringAnhui University of TechnologyMa’anshan 243002Chin

tWe proposed a facile synthesis of single-Ni-atom catalysts on low-cost porous carbon using a calcina-tion method at the temperatures of 850-1000°C,which were used for CO_(2) electrochemical reduction to *** porous carbon was prepared by carbonizing cheap and abundant humic *** structural characterizations of the as-synthesized catalysts and their electrocatalytic performances were *** results showed that the single-Ni-atom catalyst activated at 950°C showed an optimum catalytic performance,and it reached a CO Faradaic efficiency of 91.9% with a CO partial current density of 6.9 mAcm^(-2)at-0.9 V *** hydrogen electrode(RHE).Additionally,the CO Faradaic efficiency and current density of the optimum catalyst changed slightly after 8 h of continuous operation,suggesting that it possessed an excellent *** structure-activity relations indicate that the variation in the CO_(2) electroche-mical reduction performance for the as-synthesized catalysts is ascribed to the combined effects of the increase in the content of pyrrolic N,the evaporation of Ni and N,the decrease in pore volume,and the change in graphitization degree.

关键词： CO_(2) electroreduction single-Ni-atom cataly-sts humic acid based porous carbon

Hepatic non-parenchymal cells and extracellular matrix participate in oval cell-mediated liver regeneration

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World Journal of Gastroenterology 2009年第5期15卷 552-560页

作者： wei Zhang Xiao-ping chen Wan-Guang Zhang Feng Zhang Shuai Xiang Han-Hua Dong Lei Zhang Hepatic Surgery Center Tongji Hospital Tongji Medical College HuazhongUniversity of Science and Technology Wuhan 430030 HubeiProvince China

AIM： To elucidate the interaction between non- parenchymal cells, extracellular matrix and oval cells during the restituting process of liver injury induced by partial hepatectomy （PH）. METHODS： We examined the localization of oval cells, non-parenchymal cells, and the extracellular matrix components using immunohistochemical and double immunofluorescent analysis during the proliferation and differentiation of oval cells in N-2- acetylaminofluorene （2-AAF）/PH rat model. RESULTS： By day 2 after PH, small oval cells began to proliferate around the portal area. Most of stellate cells and laminin were present along the hepatic sinusoids in the periportal area. Kupffer cells and fibronectin markedly increased in the whole hepatic Iobule. From day 4 to 9, oval cells spread further into hepatic parenchyma, closely associated with stellate cells, fibronectin and laminin. Kupffer cells admixed with oval cells by day 6 and then decreased in the periportal zone. From day 12 to 15, most of hepatic stellate cells （HSCs）, laminin and fibronectin located around the small hepatocyte nodus, and minority of them appeared in the nodus. Kupffer cells were mainly limited in the pericentral sinusoids. After day 18, the normal liver Iobule structures began to ***： Local hepatic microenvironment may participate in the oval cell-mediated liver regeneration through the cell-cell and cell-matrix interactions.

关键词： Oval cells Liver regeneration Extracellularmatrix Hepatic stellate cells Kupffer cells