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Modeling of microstructural evolution and flow behavior of superalloy IN718 using physically based internal state variables

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Rare Metals 2022年第8期41卷 2759-2766页

作者： Xue-Feng Tang Bao-Yu Wang Ning Zhang yuan-ming huo Jing Zhou School of Mechanical Engineering University of Science and Technology BeijingBeijing100083China Beijing Aeronautical Manufacturing Technology Research Institute Beijing100024China

Microstructural evolution and flow behavior greatly affect the hot forming process of *** this research,hot deformation behaviors of IN718 were investigated by performing hot compression tests at temperature range of 1000-1100℃with strain rates of 0.1-20.0 s^(-1).By incorporating physically based internal state variables such as dislocation density,volume fraction of dynamic recrystallization,and grain size,a set of unified viscoplastic constitutive equations were developed to predict the microstructural evolution and flow behavior of *** material constants were determined using a genetic algorithm(G A)-based optimization *** of the computed and experimental results indicate that the constitutive equations established in this study can accurately describe the hot deformation behavior and microstructural evolution of IN718.

关键词： IN718 Microstructural evolution Flow behavior Constitutive equations Internal state variables

Dynamic Regulation of Hydrogen Bonding Networks and Solvation Structures for Synergistic Solar‑Thermal Desalination of Seawater and Catalytic Degradation of Organic Pollutants

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Nano-Micro Letters 2025年第2期17卷 548-565页

作者： ming‑yuan Yu Jing Wu Guang Yin Fan‑Zhen Jiao Zhong‑Zhen Yu Jin Qu Beijing Key Laboratory of Advanced Functional Polymer Composites Beijing University of Chemical TechnologyBeijing 100029People’s Republic of China State Key Laboratory of Organic‑Inorganic Composites College of Materials Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029People’s Republic of China

Although solar steam generation strategy is efficient in desalinating seawater,it is still challenging to achieve continuous solar-thermal desalination of seawater and catalytic degradation of organic ***,dynamic regulations of hydrogen bonding networks and solvation structures are realized by designing an asymmetric bilayer membrane consisting of a bacterial cellulose/carbon nanotube/Co_(2)(OH)_(2)CO_(3)nanorod top layer and a bacterial cellulose/Co_(2)(OH)_(2)CO_(3)nanorod(BCH)bottom ***,the hydrogen bonding networks inside the membrane can be tuned by the rich surface–OH groups of the bacterial cellulose and Co_(2)(OH)_(2)CO_(3)as well as the ions and radicals in situ generated during the catalysis ***,both SO_(4)^(2−)and HSO_(5)−can regulate the solvation structure of Na^(+)and be adsorbed more preferentially on the evaporation surface than Cl^(−),thus hindering the de-solvation of the solvated Na^(+)and subsequent nucleation/growth of ***,the heat generated by the solar-thermal energy conversion can accelerate the reaction kinetics and enhance the catalytic degradation *** work provides a flow-bed water purification system with an asymmetric solar-thermal and catalytic membrane for synergistic solar thermal desalination of seawater/brine and catalytic degradation of organic pollutants.

关键词： Solar steam generation Seawater desalination Catalytic degradation Bacterial cellulose Cobalt hydroxycarbonate nanorods

Unlocking the future:Mitochondrial genes and neural networks in predicting ovarian cancer prognosis and immunotherapy response

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World Journal of Clinical Oncology 2025年第1期16卷 43-52页

作者： Zhi-Jian Tang yuan-ming Pan Wei Li Rui-Qiong Ma Jian-Liu Wang Department of Obstetrics and Gynecology Peking University People’s HospitalBeijing 100044China Cancer Research Center Beijing Chest HospitalBeijing 101149China Department of Thoracic Surgery Sichuan Provincial People's HospitalChengdu 610072Sichuan ProvinceChina

BACKGROUND Mitochondrial genes are involved in tumor metabolism in ovarian cancer(OC)and affect immune cell infiltration and treatment *** To predict prognosis and immunotherapy response in patients diagnosed with OC using mitochondrial genes and neural *** Prognosis,immunotherapy efficacy,and next-generation sequencing data of patients with OC were downloaded from The Cancer Genome Atlas and Gene Expression *** genes were sourced from the MitoCarta3.0 *** discovery cohort for model construction was created from 70% of the patients,whereas the remaining 30% constituted the validation *** the expression of mitochondrial genes as the predictor variable and based on neural network algorithm,the overall survival time and immunotherapy efficacy(complete or partial response)of patients were *** In total,375 patients with OC were included to construct the prognostic model,and 26 patients were included to construct the immune efficacy *** average area under the receiver operating characteristic curve of the prognostic model was 0.7268[95% confidence interval(CI):0.7258-0.7278]in the discovery cohort and 0.6475(95%CI:0.6466-0.6484)in the validation *** average area under the receiver operating characteristic curve of the immunotherapy efficacy model was 0.9444(95%CI:0.8333-1.0000)in the discovery cohort and 0.9167(95%CI:0.6667-1.0000)in the validation *** The application of mitochondrial genes and neural networks has the potential to predict prognosis and immunotherapy response in patients with OC,providing valuable insights into personalized treatment strategies.

关键词： Ovarian cancer Mitochondria Prognosis Immunotherapy Neural network

Deciphering fungal metabolon coupling tandem inverse-electrondemand Diels-Alder reaction and semipinacol rearrangement for the biosynthesis of spiro polycyclic alkaloids

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Science China Chemistry 2025年第01期 288-296页

作者： Shuai Liu Wen-Qiang Xu Ying-Tong Di Man-Cheng Tang Ding-Kang Chen ming-ming Cao Yao-Wen Chang Hong-Yu Tang Chun-Mao yuan Jun-Bo Yang Zhi-Li Zuo Han Guo Zi-Fei Xu Ying Zeng Yun-Dong Wu Xiao-Jiang Hao Key Laboratory of Phytochemistry and Natural Medicines (Chinese Academy of Sciences) Kunming Institute of Botany Chinese Academy of Sciences University of Chinese Academy of Sciences Lab of Computational Chemistry and Drug Design State Key Laboratory of Chemical Oncogenomics Peking University Shenzhen Graduate School Shenzhen Bay Laboratory State Key Laboratory of Microbial Metabolism School of Life Sciences & Biotechnology Shanghai Jiao Tong University State Key Laboratory of Functions and Applications of Medicinal Plants Guizhou Medical University Molecular Biology Experimental Center Germplasm Bank of Wild Species in Southwest China Kunming Institute of Botany Chinese Academy of Sciences Yunnan Key Laboratory for Wild Plant Resources Kunming Institute of Botany Chinese Academy of Sciences Research Unit of Chemical Biology of Natural Anti-Virus Products Chinese Academy of Medical Sciences

In the intricate process of natural product biosynthesis, a metabolon can enhance metabolic flux by associating sequential enzymes. A fungal metabolon, comprising of flavin-dependent monooxygenase Spe F and P450 monooxygenase Spe G, is identified in the biosynthesis of spiro polycyclic alkaloids(+)-notoamide B and its diastereomer(+)-versicolamide B. Using notoamide E as a substance, Spe F/Spe G metabolon can control the stereoselectivity of its 2,3-epoxidation, followed by hydrogen atom ion at C-17 to generate reactive epoxide tau-m A with dienyl iminium unit. Subsequently,(+)-notoamide B and(+)-versicolamide B are produced via tandem nonenzymatic inverse-electron-demand Diels-Alder reaction and semipinacol rearrangement. This provides the first example of metabolon in the biosynthesis of spiro-prenylated indole alkaloids.

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A New Organo-templated Layered Zincophosphate Synthesized from a Solvothermal System Containing Racemic 1,2-Diaminopropane

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Chemical Research in Chinese Universities 2002年第4期18卷 375-379页

作者： CHEN Wei yuan Hong-ming JIANG Yu-sheng huo Hua CHEN Jie-sheng State Key Laboratory of Inorganic Synthesis and Preparative Chemistry Jilin UniversityChangchun 130023P.R.China

A new layered zincophosphate was synthesized under solvothermal conditions by employing racemic 1,2-diaminopropane as the structure-directing agent. The structure of the compound was solved by means of single-crystal X-ray diffraction analysis. It crystallized in the monoclinic space group P2_1/c (No. 14) with a= 1.047 0(3) nm, b=0.787 31(18) nm, c=0.662 68(16) nm, β=103.120(5)°, V=0.532 0(2) nm 3 and Z=4. The structure is made up of anionic zincophosphate sheets stacked in an AAAA sequence. The individual sheet contains three- and four-membered rings and the infinite Zn-O-Zn chains can also be envisaged in the sheet. The charge-balancing diprotonated racemic 1,2-diaminopropane cations are sandwiched between the layers, whereas the inorganic layers are stabilized by strong H-bonds formed between the N atoms of the amine and the O atoms in the inorganic sheets.

关键词： Layered zincophosphate X-ray diffraction Crystal structure Racemic system

不同施肥处理对高寒草地地上生物量及植物群落特征的影响

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草原与草坪 2017年第3期37卷 91-96页

作者：王娟焦婷聂中南祁娟张德罡肖元明霍诗梅甘肃农业大学草业学院/草业生态系统教育部重点实验室/甘肃省草业工程实验室/中-美草地畜牧业可持续发展研究中心甘肃兰州730070 Department of Environment and Primary Industries

试验以天祝高寒放牧草地植物为研究对象,进行了8种肥料(N,P,K,Zn,Cu,Mo,Se,B)的根部喷施试验,于7月和8月份测定不同处理草地植物群落特征。结果表明:除禾草类群外,各施肥处理对天祝高寒草地不同植物学类群地上生物量影响不显著(P>0.05)... 详细信息

试验以天祝高寒放牧草地植物为研究对象,进行了8种肥料(N,P,K,Zn,Cu,Mo,Se,B)的根部喷施试验,于7月和8月份测定不同处理草地植物群落特征。结果表明:除禾草类群外,各施肥处理对天祝高寒草地不同植物学类群地上生物量影响不显著(P>0.05),氮肥提高了禾草类植物的生物量,但与对照差异不显著;施肥处理对赖草(Leymus secalinus)、早熟禾(Poa pratensis)的盖度以及赖草的密度有极显著影响(P<0.01)。

关键词：施肥高寒草地地上生物量群落特征

Degrees of freedom in low rank matrix estimation

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Science China Mathematics 2016年第12期59卷 2485-2502页

作者： yuan ming Department of Statistics University of Wisconsin-Madison

The objective of this paper is to quantify the complexity of rank and nuclear norm constrained methods for low rank matrix estimation problems. Specifically, we derive analytic forms of the degrees of freedom for these types of estimators in several common settings. These results provide efficient ways of comparing different estimators and eliciting tuning parameters. Moreover, our analyses reveal new insights on the behavior of these low rank matrix estimators. These observations are of great theoretical and practical importance. In particular, they suggest that, contrary to conventional wisdom, for rank constrained estimators the total number of free parameters underestimates the degrees of freedom, whereas for nuclear norm penalization, it overestimates the degrees of freedom. In addition, when using most model selection criteria to choose the tuning parameter for nuclear norm penalization, it oftentimes suffices to entertain a finite number of candidates as opposed to a continuum of choices. Numerical examples are also presented to illustrate the practical implications of our results.

关键词： degrees of freedom low rank matrix approximation model selection nuclear norm penalization reduced rank regression Stein's unbiased risk estimator

BASIC HYDRODYNAMICS CHARACTERISTICS OF CAVITY SPIRAL FLOW IN A LARGE SIZE LEVEL PIPE

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Journal of Hydrodynamics 2005年第4期17卷 503-513页

作者： NIU Zheng-ming ZHANG ming-yuan School of Energy and Power Engineering Xi＇an Jiaotong University Xi＇an 710048 China

Based on the observation of a model test and in combination with some theoretical analysis, the researches of some basic hydrodynamics characteristics of cavity spiral flow in a large size level pipe with a shaft-inlet is presented in the paper, which include the basic flow pattern, formation condition of the cavity spiral flow, discharge Q, cavity diameter d0, wall pressure coefficient Cpw, velocity distribution, total energy dissipation rate η etc. The results show that the basic flow patterns can be divided into three zones according to the variations in amount of ventilation Ф, cavity diameter d0 and gas pressure p0 within cavity spiral flow when the upstream and downstream water level changes and that the basic hydrodynamics characteristics change with the flow pattern and have the different behaviour.

关键词： hydrodynamics characteristics flow pattern zoning change cavity spiral flow large size level pipe

An iterative time-marching scheme for the investigation of hydrodynamic interaction between multi-ships during overtaking

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Journal of Hydrodynamics 2021年第3期33卷 468-478页

作者： ming-Xin Li Zhi-ming yuan Longbin Tao Department of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang212008China Department of Naval Architecture Ocean and Marine EngineeringUniversity of StrathclydeGlasgowUK

An iterative time-marching scheme is developed to investigate the hydrodynamic interactions between multiple *** an unsteady interactive effect could be magnified in restricted waterways,e.g.,a channel or harbor *** the author’s knowledge,nearly all the research on the ship-to-ship interaction neglecting the free surface *** free surface is usually treated as a rigid *** assumption is only reasonable when the speed of the ships is very low in deep water condition,due to the hydrodynamic interaction between the ships is mainly induced by near-field ***,when the moving speeds are moderately higher,especially with a small lateral separation between ships,the far-field effects arising from the ship waves become *** main objective of the present paper is to develop an iterative time-matching algorithm to solve the hydrodynamic interaction between high-speed ships taking into account the nonlinear free surface boundary condition in time domain.

关键词： Iterative time-marching scheme hydrodynamic interaction multi-ships free surface