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Study Over Thermal State of Gas Turbine Engine Metal-ceramic Rotor Blades and Nozzle Guide vanes Under Thermal Shock and Thermal-cyclic loading Conditions

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Journal of Thermal Science 2004年第2期13卷 163-166页

作者： A.v.SOUDAREv A.A. SOURyaNINOv v.ya. PODGORETS v.v.GRISHAEv v.Yu. TIKHOPlAv A.S. MOlCHANOv B.v. SOUDAREv Research-Engineering "Ceramic Heat Engines" Center St.Petersburg Russia

To ensure a reliable operation of the 2.5 MW gas turbine engine (GTE- 2.5) with the inlet gas temperature TIT = 1623 K, studies were performed over the thermal state of the nozzle guide vanes and rotor blades with the temperatures, rates and flows of the working media and cooling air simulating all the potential turbine stage operating duties. The steady state and thermal-cyclic tests having been accomplished, there was no visible defect on the rotor blades and the nozzle vanes. Afterwards, they survived the endurance tests at the rated cooling. Therefore, the functionality of the shell thin-wall hybrid nozzle vanes and rotor blades under the variable operating duties of the gas turbine at the 'shock' and 'cyclic' loads of the working media temperature variations has been demonstrated.

关键词： metal-ceramic blades high temperature thermal-cyclic loading

Stochastic DoS Attack Allocation Against Collaborative Estimation in Sensor Networks

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IEEE/CAA Journal of Automatica Sinica 2020年第5期7卷 1225-1234页

作者： ya Zhang lishuang Du Frank l.lewis School of Automation Southeast Universityand also with the Key Laboratory of Measurement and Control of Complex Systems of EngineeringMinistry of EducationNanjing 210096China University of Texas at Arlington Research Institute Fort WorthTX 76118 USA IEEE

In this paper,denial of service(DoS)attack management for destroying the collaborative estimation in sensor networks and minimizing attack energy from the attacker perspective is *** the communication channels between sensors and a remote estimator,the attacker chooses some channels to randomly jam DoS attacks to make their packets randomly dropped.A stochastic power allocation approach composed of three steps is ***,the minimum number of channels and the channel set to be attacked are ***,a necessary condition and a sufficient condition on the packet loss probabilities of the channels in the attack set are provided for general and special systems,***,by converting the original coupling nonlinear programming problem to a linear programming problem,a method of searching attack probabilities and power to minimize the attack energy is *** effectiveness of the proposed scheme is verified by simulation examples.

关键词： Attack allocation denial of service(DoS)attack packet loss remote estimation sensor networks

Analytic time-of-flight positron emission tomography reconstruction: threedimensional case

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visual Computing for Industry,Biomedicine,and Art 2020年第1期3卷 39-52页

作者： Gengsheng l.Zeng ya li Qiu Huang Department of Engineering Utah Valley University800 West University ParkwayOremUT 84058USA Department of Radiology and Imaging Sciences University of Utah729 Arapeen DriveSalt Lake CityUT 84108USA Department of Mathematics Utah Valley University800 West University ParkwayOremUT 84058USA School of Biomedical Engineering Shanghai Jiaotong UniversityShanghai 200240China

In a positron emission tomography(PET)scanner,the time-of-flight(TOF)information gives us rough event position along the line-of-response(lOR).Using the TOF information for PET image reconstruction is able to reduce image *** state-of-the-art TOF PET image reconstruction uses iterative *** study introduces an analytic TOF PET algorithm that focuses on three-dimensional(3D)*** proposed algorithm is in the form of backprojection filtering,in which the backprojection is performed first by using a time-resolution profile function,and then a 3D filter is applied to the backprojected *** the list-mode data,the backprojection is carried out in the event-by-event fashion,and the timing resolution determined weighting function is used along the projection *** simulations are carried out to verify the feasibility of the proposed algorithm.

关键词： Positron emission tomography Time-of-flight Analytic reconstruction

Exclusive π^(0) production at EIC of China within handbag approach

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Chinese Physics C 2022年第12期46卷 50-57页

作者： S.v.Goloskokov ya-Ping Xie Xurong Chen laboratory of Theoretical Physics Joint Institute for Nuclear ResearchDubna 141980MoscowRussia Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China Institute of Quantum Matter South China Normal UniversityGuangzhou 510006China

Exclusive π^(0) electroproduction is analyzed within the handbag approach based on Generalized Parton Distribution(GPDs)*** consider the leading-twist contribution together with the transversity *** is shown that the transversity GPDs H_(T) and E_(T) are essential in the description of the π^(0) cross *** for the future Electron-Ion Collider of China(EicC)energy range are *** is found that transversity dominanceσ_(T)>>σ_(l),observed at low energies,is valid up to the EicC energy range.

关键词： general parton distributions nucleon structure deep virtual meson production

STRESS-STRAIN STATE OF ElASTOPlASTIC BODIES WITH CRACK

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Acta Mechanica Solida Sinica 2015年第4期28卷 375-383页

作者： v.v.Glagolev l.v.Glagolev A.A.Markin Tula State University

A physical cut model is used to describe the changes in the stress-strain state （SSS） in elastoplastic bodies weakened by cracks. The distance between the crack edges is considered to be finite in contrast to the mathematical cut. The interactive layer with a thickness limited by the possibility of using the hypothesis of continuity is distinguished on the physical cut extension, Distribution of stresses and strains over the layer thickness is constant and does not depend on the geometry of the boundary between the cut and the interactive layer. The relationship between stresses and strains is determined by the deformation plasticity theory. The problem of plane strain or plane stress state of an arbitrary finite body weakened by a physical cut is reduced to solving a system of two variational equations for displacement fields in the body parts adjacent to the interactive layer. The proposed approach eliminates the singularity in stress distribution in contrast to the mathematical cut model. Use of local strength criteria allows us to determine the time, point and direction of the fracture initiation. Possibilities of the proposed model are illustrated by solving the problems of determining the SSS of a rectangular body weakened by a physical cut under symmetric and antisymmetric loadings.

关键词： crack physical cut characteristic size elastoplastic deformations

Cylinder Pressure Prediction of An HCCI Engine Using Deep learning

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Chinese Journal of Mechanical Engineering 2021年第2期34卷 160-167页

作者： Halit yaşar GültekinÇağıl Orhan Torkul MerveŞişci Department of Mechanical Engineering Engineering FacultySakarya UniversityEsentepe Campus54187 SerdivanSakaryaTurkey Department of Industrial Engineering Engineering FacultySakarya UniversityEsentepe Campus54187 SerdivanSakaryaTurkey

Engine tests are both costly and time consuming in developing a new internal combustion ***,it is of great importance to predict engine characteristics with high accuracy using artificial ***,it is possible to reduce engine testing costs and speed up the engine development *** learning is an effective artificial intelligence method that shows high performance in many research areas through its ability to learn high-level hidden features in data *** present paper describes a method to predict the cylinder pressure of a Homogeneous Charge Compression Ignition(HCCI)engine for various excess air coefficients by using Deep Neural Network,which is one of the Deep learning methods and is based on the Artificial Neural Network(ANN).The Deep learning results were compared with the ANN and experimental *** results show that the difference between experimental and the Deep Neural Network(DNN)results were less than 1%.The best results were obtained by Deep learning *** cylinder pressure was predicted with a maximum accuracy of 97.83%of the experimental value by using *** the other hand,the accuracy value was increased up to 99.84%using *** results show that the DNN method can be used effectively to predict cylinder pressures of internal combustion engines.

关键词： Artificial neural network Deep neural network HCCI engine Cylinder pressure Excess air coefficient

绿原酸对中性粒细胞功能及胞外诱捕网形成的影响及机制

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中国药理学通报 2025年第1期41卷 101-107页

作者：杨运刘娅王翠彭春红贵州中医药大学第二临床医学院贵州贵阳550025 七星关区中医妇幼集团医院贵州毕节551700 毕节市中医医院贵州毕节551700 贵州医科大学临床医学院贵州贵阳550025 贵州省人民医院呼吸与危重医学科贵州贵阳550002 国家卫健委肺脏免疫性疾病重点实验室贵州贵阳550002

目的探究绿原酸(chlorogenic acid,CGA)对中性粒细胞(neutrophil,NEU)功能及中性粒细胞胞外诱捕网(neutrophil extracellular traps,NETs)形成的影响及机制。方法从小鼠骨髓中分离并纯化NEU;将NEU与CGA共培养,通过CCK-8法筛选共培养适合的干预浓度;检测NEU迁移能力、髓过氧化物酶(MPO)以及脱颗粒弹性蛋白酶(NE)、基质金属蛋白酶9(MMP-9)的水平观察CGA对NEU功能的影响;免疫荧光法观察NETs的主要结构组蛋白H3及DNA骨架,以及检测NEU释放的游离DNA(cf-DNA)含量,观察NETs的形成情况;检测NEU产生的活性氧(ROS)水平,以确定CGA是否影响NEU释放NETs过程中的ROS的生成。结果CGA在浓度为100、200、400μmol·l^(-1)时对NEU活性有明显抑制作用(Plank)相比,CGA(100、200、400μmol·l^(-1))干预后,细胞迁移能力及MPO、NE、MMP-9分泌量增加(P<0.05),组蛋白H3及DNA骨架、cf-DNA的释放量明显增加(P<0.01),细胞产生的ROS也明显增加(P<0.01),上述作用在一定范围内具有浓度依赖性。结论CGA能够增强NEU功能及促进NETs的形成,可能与促进细胞内ROS水平增加有关。

关键词：绿原酸中性粒细胞胞外诱捕网免疫抗菌活性氧

Influence of Turbulence Intensity and Turbulence length Scale on the Drag, lift and Heat Transfer of A Circular Cylinder

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China Ocean Engineering 2017年第3期31卷 357-363页

作者： I.v. Morenko v.l. Fedyaev Institute of Mechanics and Engineering Kazan Science Center Russian Academy of Sciences (IME KazSC RAS) Kazan Russian Federation Kazan National Research Technical University named after A.N. Tupolev - KAI (KNRTU-KAI) Kazan Russian Federation

Influence of the turbulence intensity and turbulence length scale on the hydrodynamic characteristics and heat transfer of a circular cylinder, streamlined by a viscous fluid flow, is numerically studied. We take the Reynolds number of the oncoming flow equal to 4×10^4, the turbulence intensity Tuf and the dimensionless turbulence length scale l-f varying from 1.0% to 40% and from 0.25 to 4.0, respectively. We confirmed that the increase of Tuf leads to the suppression of the periodic vortex shedding from the cylinder surface, and as a result the stationary mode of streamlining is formed. Consequently, with the increasing turbulence intensity directly in front of the cylinder Tu＊, the amplitude of the lift coefficient decreases monotonically. Nevertheless, the time-averaged drag coefficient of the streamlined cylinder decreases at Tu＊〈6.0%, and increases at Tu＊〉9.0%. The dependence of the average Nusselt number on Tu＊ is near-linear, and with the increasing turbulence intensity, the Nusselt number rises. However, the change of the average Nusselt number depending on l-f is non-monotonic and at lf=l.0, the value reaches its maximum

关键词： hydrodynamics turbulence heat transfer of a circular cylinder

Recovery of valuable metals from a low-grade nickel ore using an ammonium sulfate roasting-leaching process

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International Journal of Minerals,Metallurgy and Materials 2012年第5期19卷 377-383页

作者： Xin-wei l iu ya-li Feng Hao-ran l i Zhi-chao yang Zhen-lei Cai Civil and Environmental Engineering School University of Science and Technology Beijing 100083 China National Key State laboratory of Biochemical Engineering Institute of Process Engineering Chinese Academy of Science Beijing 100190 China

Metal leaching from a low-grade nickel ore was investigated using an ammonium sulfate roasting-water leaching process. The nickel ore was mixed with ammonium sulfate, followed by roasting and finally leaching with water. During the process the effects of the amotmt of ammonium sulfate, roasting temperature, and roasting time on the leaching recovery of metal elements were analyzed. The optimum technological parameters were determined as follows： ammonium sulfate/ore ratio, 0.8 g/g; roasting temperature, 400℃; and roasting time, 2 h. Under the optimum condition the leaching recoveries ofNi, Cu, Fe, and Mg were 83.48%, 76.24%, 56.43%, and 62.15%, respectively. Furthermore, the dissolution kinetics of Ni and Mg from the nickel ore was studied. The apparent activation energies for the leaching reaction of Ni and Mg were 18.782 and 10.038 ***1-1, which were consistent with the values of diffusion control reactions. Therefore, the results demonstrated that the leaching recoveries of Ni and Mg were controlled by diffusion.

关键词： nickel ore treatment ammonium sulfate roasting leaching kinetics diffusion