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Journal of Iron and Steel Research(International) 2017年第12期24卷 1254-1260页

作者： Yong Liu jing-chuan zhu Yong Cao School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001HeilongjiangChina National Key Laboratory for Metal Precision Hot Processing of Metals Harbin 150001HeilongjiangChina

Materials data deep-excavation is very important in materials genome exploration.In order to carry out materials data deep-excavation in hot die steels and obtain the relationships among alloying elements,heat treatment parameters and materials properties,a 11×12×12×4 back-propagation（BP）artificial neural network（ANN）was set up.Alloying element contents,quenching and tempering temperatures were selected as input;hardness,tensile and yield strength were set as output parameters.The ANN shows a high fitting precision.The effects of alloying elements and heat treatment parameters on the properties of hot die steel were studied using this model.The results indicate that high temperature hardness increases with increasing alloying element content of C,Si,Mo,W,Ni,V and Cr to a maximum value and decreases with further increase in alloying element content.The ANN also predicts that the high temperature hardness will decrease with increasing quenching temperature,and possess an optimal value with increasing tempering temperature.This model provides a new tool for novel hot die steel design.

关键词： Back-propagation artificial neural network Hot die steel Alloying element Heat treatment

First-principles calculations of structural,elastic and electronic properties of(TaNb)0.67(HfZrTi)0.33 high-entropy alloy under high pressure

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International Journal of Minerals,Metallurgy and Materials 2020年第10期27卷 1405-1414页

作者： Zhi-sheng Nong Hao-yu Wang jing-chuan zhu School of Materials Science and Engineering Shenyang Aerospace UniversityShenyang 110136China School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China

To clarify the effect of pressure on a(TaNb)0.67(HfZrTi)0.33 alloy composed of a solid solution with a single body-centered-cubic crystal structure,we used first-principles calculations to theoretically investigate the structural,elastic,and electronic properties of this alloy at different pressures.The results show that the calculated equilibrium lattice parameters are consistent with the experimental results,and that the normalized structural parameters of lattice constants and volume decrease whereas the total enthalpy differenceΔE and elastic constants increase with increasing pressure.The(TaNb)0.67(HfZrTi)0.33 alloy exhibits mechanical stability at high pressures lower than 400 GPa.At high pressure,the bulk modulus B shows larger values than the shear modulus G,and the alloy exhibits an obvious anisotropic feature at pressures ranging from 30 to 70 GPa.Our analysis of the electronic structures reveals that the atomic orbitals are occupied by the electrons change due to the compression of the crystal lattices under the effect of high pressure,which results in a decrease in the total density of states and a wider electron energy level.This factor is favorable for zero resistance.

关键词： first-principles calculations elastic property electronic structure density of states high-entropy alloys high pressure

Electronic structure and optical properties of non-metallic modified graphene:a first-principles study

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Communications in Theoretical Physics 2022年第3期74卷 70-76页

作者： jing-tao Huang Yong Liu Zhong-hong Lai Jin Hu Fei Zhou jing-chuan zhu School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China National Key Laboratory for Precision Hot Processing of Metals Harbin Institute of TechnologyHarbin 150001China Center for analysis measurement and computingHarbin Institute of TechnologyHarbin 150001China MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage School of Chemistry and Chemical EngineeringHarbin Institute of TechnologyHarbin 150001China

In this paper,the electronic structure and stability of the intrinsic,B-,N-,Si-,S-doped graphene are studied based on first-principles calculations of density functional theory.Firstly,the intrinsic,B-,N-,Si-,S-doped graphene structures are optimized,and then the forming energy,band structure,density of states,differential charge density are analyzed and calculated.The results show that Band Si-doped systems are p-type doping,while N is n-type doping.By comparing the forming energy,it is found that N atoms are more easily doped in graphene.In addition,for B-,N-,Si-doped systems,it is found that the doping atoms will open the band gap,leading to a great change in the band structure of the doping system.Finally,we systematically study the optical properties of the different configurations.By comparison,it is found that the order of light sensitivity in the visible region is as follows:S-doped>Si-doped>pure>B-doped>N-doped.Our results will provide theoretical guidance for the stability and electronic structure of non-metallic doped graphene.

关键词： Graphene Non-metallic Electronic structure Optical properties Density functional theory

Parameters optimization design of quenching and partitioning for best combination between strength and ductility using orthogonal experimental design

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Journal of Iron and Steel Research(International) 2019年第10期26卷 1088-1095页

作者： Ming-qing Liao Zhong-hong Lai Aorigele Bao Yong Liu Dan-ni Yang Tian-yi Han jing-chuan zhu Rong-da Zhao School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001HeilongjiangChina The Center of Analysis Measurement Harbin Institute of TechnologyHarbin 150001HeilongjiangChina National Key Laboratory for Precision Hot Processing of Metals Harbin Institute of TechnologyHarbin 150001HeilongjiangChina School of Materi

Quenching and partitioning(Q&P)which provides a balance between toughness and strength is a promising heat treatment in iron and steel industry.However,there are three parameters(quenching temperature,partitioning temperature and partitioning time)which affect the properties dramatically.As a result,it remains a challenge to get the best parameters in a low-cost way for Q&P process.Here,the orthogonal experimental design combined with a local optimization was adopted to optimize the quenching and partitioning parameters of 65Si2MnWA steel.By using this method,the combination between strength and ductility was optimized;meanwhile,the number of experiments was reduced significantly.When treated by quenching at 180℃followed by partitioning at 330℃for 20 min,the steel reached the best combination between strength and ductility.In detail,the product of ultimate tensile strength and reduction in area was 1.36 times(from 64.9 to 88.8 GPa%)that treated by quenching and tempering.In addition,owing to the grain refinement,the strength and ductility increase simultaneously.Specifically,the reduction in area increased by 27.4%(from 35.8%to 45.6%)coupled with a little improvement in ultimate tensile strength(7.4%).

关键词： Parameter optimization design Quenching and partitioning Orthogonal experimental design Mechanical property 65Si2MnWA steel

Advances in the differentiation of pluripotent stem cells into vascular cells

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World Journal of Stem Cells 2024年第2期16卷 137-150页

作者： Yi-Chang Jiao Ying-Xin Wang Wen-zhu Liu jing-Wen Xu Yu-Ying Zhao chuan-zhu Yan Fu-Chen Liu Department of Neurology Qilu Hospital of Shandong UniversityJinan 250012Shandong ProvinceChina Research Institute of Neuromuscular and Neurodegenerative Diseases Qilu Hospital of Shandong UniversityJinan 250012Shandong ProvinceChina Mitochondrial Medicine Laboratory Qilu Hospital(Qingdao)of Shandong UniversityQingdao 266103Shandong ProvinceChina Brain Science Research Institute Shandong UniversityJinan 250012Shandong ProvinceChina

Blood vessels constitute a closed pipe system distributed throughout the body,transporting blood from the heart to other organs and delivering metabolic waste products back to the lungs and kidneys.Changes in blood vessels are related to many disorders like stroke,myocardial infarction,aneurysm,and diabetes,which are important causes of death worldwide.Translational research for new appro-aches to disease modeling and effective treatment is needed due to the huge socio-economic burden on healthcare systems.Although mice or rats have been widely used,applying data from animal studies to human-specific vascular physiology and pathology is difficult.The rise of induced pluripotent stem cells(iPSCs)provides a reliable in vitro resource for disease modeling,regenerative medicine,and drug discovery because they carry all human genetic information and have the ability to directionally differentiate into any type of human cells.This review summarizes the latest progress from the establishment of iPSCs,the strategies for differentiating iPSCs into vascular cells,and the in vivo trans-plantation of these vascular derivatives.It also introduces the application of these technologies in disease modeling,drug screening,and regenerative medicine.Additionally,the application of high-tech tools,such as omics analysis and high-throughput sequencing,in this field is reviewed.

关键词： Induced pluripotent stem cell Blood vessels Vascular organoids Endothelial cells Smooth muscle cells Pericytes Tissue engineering vascular graft

Catalytic enantioselective N-silylation of sulfoximine

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Chinese Chemical Letters 2024年第4期35卷 352-356页

作者： Xingfen Huang Jiefeng zhu chuan He Shenzhen Grubbs Institute and Department of Chemistry Guangdong Provincial Key Laboratory of CatalysisSouthern University of Science and TechnologyShenzhen 518055China Key Laboratory of Organosilicon Chemistry and Material Technology of Ministry of Education Hangzhou Normal UniversityHangzhou 311121China

A rhodium/diphosphine-catalyzed asymmetric cross-dehydrogenative coupling between sulfoximines and dihydrosilanes has been achieved. This is the first report on the enantioselective N-silylation of sulfoximines. The protocol gives access to a variety of Si-stereogenic N-silylated sulfoximines in decent yield(up to 99%) with excellent stereoselectivity(up to 99%), featuring high atom economy, and a cleaner manner with H2as the sole byproduct. The obtained bis-Si-stereogenic monohydrosilane product can be further converted into the corresponding chiral polymer with pendant sulfoximine groups.

关键词： N-Silylation of sulfoximine Chiral silylamine Si-stereogenic silanes Si-CADC Asymmetric catalysis

EGFR-targeted and gemcitabine-incorporated chemogene for combinatorial pancreatic cancer treatment

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Nano Research 2024年第2期17卷 848-857页

作者： Miao Xie Qiushuang Zhang Yuanyuan Guo Lijuan zhu Xinyuan zhu chuan Zhang School of Chemistry and Chemical Engineering Frontiers Science Center for Transformative MoleculesInstitute of Molecular MedicineSixth people’s HospitalSchool of MedicineShanghai Key Laboratory for Molecular Engineering of Chiral DrugsShanghai Jiao Tong UniversityShanghai 200240China Department of Radiology Shanghai Jiao Tong University Affiliated Sixth People’s HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghai 200233China Institute of Molecular Medicine Shanghai Jiao Tong University Affiliated Renji HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghai 200127China

Pancreatic cancer stands out as a recognized intractable tumor due to its high malignancy and mortality rates,which are largely attributed to the insensitivity of current clinical chemotherapies or multidrug-resistance.Combinatorial chemo and gene therapy that integrates different therapeutic targets,may increase the chemosensitivity of pancreatic cancer and synergistically enhance the antitumor efficacy.However,conventional co-delivery of gene and chemo drugs is intensively dependent on complex nanoparticle delivery systems,thus would be limited by unstable drug packaging,nonspecific biodistribution,and biosafety problem.Herein,we rationally designed an epidermal growth factor-receptor(EGFR)-targeted and gemcitabine-incorporated oligonucleotide(termed as chemogene)with anti-Bcl-2 sequence,which achieves simple and precise integration of gemcitabine into a gene regulative agent,as well as the EGFR-targeted delivery for pancreatic cancer therapy.Through solid-phase synthesis,gemcitabine,as the first-line chemodrug for pancreatic cancer,is introduced to the antisense oligonucleotide to replace all cytosine nucleosides to obtain the gemcitabine-integrated chemogene(Ge-ASO^(Bcl-2)).Thereafter,Ge-ASO^(Bcl-2)is covalently coupled with EGFR nanobody to construct the final targeted chemogene without any exogenous carriers.Notably,this nanobody-conjugated chemogene exhibits remarkable tumor targeting capability and antitumor effects both in vitro and in vivo,which initiates a first step toward the application of combinatorial chemo and gene therapy for future pancreatic cancer treatment.

关键词： antisense oligonucleotide chemogene nanobody drug delivery system pancreatic cancer

The posterior selection method for hyperparameters in regularized least squares method

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Control Theory and Technology 2024年第2期22卷 184-194页

作者： Yanxin Zhang jing Chen Yawen Mao Quanmin zhu School of Science Jiangnan UniversityWuxi214122JiangsuChina The Science and Technology on Near-Surface Detection Laboratory Wuxi214122JiangsuChina Department of Engineering Design and Mathematics University of the West of EnglandBristolBS161QYUK

The selection of hyperparameters in regularized least squares plays an important role in large-scale system identification. The traditional methods for selecting hyperparameters are based on experience or marginal likelihood maximization method, which are inaccurate or computationally expensive. In this paper, two posterior methods are proposed to select hyperparameters based on different prior knowledge (constraints), which can obtain the optimal hyperparameters using the optimization theory. Moreover, we also give the theoretical optimal constraints, and verify its effectiveness. Numerical simulation shows that the hyperparameters and parameter vector estimate obtained by the proposed methods are the optimal ones.

关键词： Regularization method Hyperparameter System identification Least squares algorithm

Transitional Revenue Scheme for High-cost Generator Unit in Guangdong Electricity Market Based on Government Authorized Contracts

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CSEE Journal of Power and Energy Systems 2024年第1期10卷 208-221页

作者： Jisong zhu Baike Chen Tianyao Ji Zhaoxia jing School of Electric Power Engineering South China University of TechnologyGuangzhou 510640China

High-cost generator units are at a cost disadvantage in electricity spot markets.This study focuses on revenue mechanisms of gas-fired units affected by power market reform in Guangdong province,China.For the first time,we compare impacts on market indicators of five settlement mechanisms:feed-in tariff(FiT),location marginal price(LMP),contract for difference(CFD),direct subsidy(DS),and estimated revenue method(ERM).In particular,we design key parameters,including authorized CFD and ERM of two kinds of government authorized contracts based on traditional dispatching patterns to avoid significant profit fluctuations brought by market reforms.We also analyze impact of factors such as climbing performance,seasonal load,and subsidy amount on the overall market and its players.Results of a case study show to directly subsidize gasfired units will lead higher-cost units to generate more electricity,with a resulting loss of social welfare.Disruption of market prices and provision of unreasonable incentives are fatal disadvantages of this subsidy method.The government and policymakers should consider financial means to adjust benefits to reduce production costs and increase social welfare.Also,by case analysis,the ERM shows its stable performance in revenue of high-cost units,while we find that authorized CFD is not applicable for gas-fired units whose output is unstable as a marginal unit frequently.Therefore,we suggest government agencies adopt ERM to sign contracts with gas-fired units,to attain a balance between fairness and efficiency.

关键词： Guangdong electricity market high-cost generator unit settlement mechanism subsidy

Carbon-based interface engineering and architecture design for high-performance lithium metal anodes

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Carbon Energy 2024年第1期6卷 207-235页

作者： Na zhu Yuxiang Yang Yu Li Ying Bai Junfeng Rong chuan Wu SINOPEC Research Institute of Petroleum Processing Co. Ltd.BeijingChina Beijing Key Laboratory of Environmental Science and Engineering School of Materials Science and EngineeringBeijing Institute of TechnologyBeijingChina Yangtze Delta Region Academy of Beijing Institute of Technology JiaxingChina

Metallic lithium(Li)is considered the“Holy Grail”anode material for the nextgeneration of Li batteries with high energy density owing to the extraordinary theoretical specific capacity and the lowest negative electrochemical potential.However,owing to inhomogeneous Li-ion flux,Li anodes undergo uncontrollable Li deposition,leading to limited power output and practical applications.Carbon materials and their composites with controllable structures and properties have received extensive attention to guide the homogeneous growth of Li to achieve high-performance Li anodes.In this review,the correlation between the behavior of Li anode and the properties of carbon materials is proposed.Subsequently,we review emerging strategies for rationally designing high-performance Li anodes with carbon materials,including interface engineering(stabilizing solid electrolyte interphase layer and other functionalized interfacial layer)and architecture design of host carbon(constructing three-dimension structure,preparing hollow structure,introducing lithiophilic sites,optimizing geometric effects,and compositing with Li).Based on the insights,some prospects on critical challenges and possible future research directions in this field are concluded.It is anticipated that further innovative works on the fundamental chemistry and theoretical research of Li anodes are needed.

关键词： carbon materials dendrites hosts interfacial layers Li metal anodes