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Application of ultrasonic fatigue technology in very-high-cycle fatigue testing of aviation gas turbine engine blade materials:A review

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Science China(Technological Sciences) 2024年第5期67卷 1317-1363页

作者： zhao JiuCheng WAN Jie ZHANG ShiZhong yan ChuLiang zhao HongWei Key Laboratory of CNC Equipment Reliability Ministry of Education Jilin UniversityChangchun 130025China School of Mechanical&Aerospace Engineering Jilin UniversityChangchun 130025China Chongqing Research Institute of Jilin University Chongqing401120China School of Aeronautic Science and Engineering Beihang UniversityBeijing 102206China

The need for very-high-cycle fatigue(VHCF)testing up to 1010cycles of aviation gas turbine engine blade materials under combined mechanical loads and complex environments has encouraged the development of VHCF testing instrumentation and *** article begins with a comprehensive review of the existing available techniques that enable VHCF *** advances in ultrasonic fatigue testing(UFT)techniques are highlighted,containing their new capabilities and methods for single load,multiaxial load,variable amplitude fatigue,and combined cycle *** techniques for conducting UFT in high-temperature,humid environments,and corrosive environments are *** developments in mechanical loading and environmental building techniques provide the possibility of laboratory construction for real service conditions of blade *** techniques that can be used for in situ monitoring of VHCF damage are *** issues in the UFT field are presented,and countermeasures are ***,the existing problems and future trends in the field are briefly described.

关键词： aviation gas turbine engine blade materials ultrasonic fatigue very-high-cycle fatigue high-temperature complex stress in situ testing

Integrated separation-electrochemical detection device based on wood column for online identification of enantiomer

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Nano Research 2024年第3期17卷 1893-1901页

作者： Junli Guo Yuanfei Xue Chenxi zhao Junjian zhao Zhida Gao Ye Mei yan-yan Song College of Sciences Northeastern UniversityShenyang 110004China State Key Laboratory of Precision Spectroscopy School of Physics and Electronic ScienceEast China Normal UniversityShanghai 200062China NYU-ECNU Center for Computational Chemistry at NYU Shanghai Shanghai 200062China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China

Chiral chemicals have attracted significant interest in the pharmaceutical industry,yet the separation methods to get pure enantiomers from racemic mixture are still *** date,the separation of enantiomers still mainly depends on chromatography using high-cost chiral stationary ***,wood channels were used as the handheld integrated device,and enantiomer separation was simultaneously detected using an electrochemical *** this method,a chiral UIO-66(L-UIO-66)modified enantiomer separation zone and carbonized wood based online detection zone are integrated along a single wood *** on the in situ separation results from the chronoamperometry data,the wood device shows excellent separation ability for a wide range of electrochemically active enantiomers,including 3,4-dihydroxyphenylalanine,amino acids,ascorbic acid,carnitine,and penicillamine with high chirality *** unbiased molecular dynamic simulations indicate that the excellent chiral recognition and separation are attributed to the different barriers from the bound states to the dissociated state of the enantiomers in the homochiral microenvironment of the *** integrated enantiomer separation-electrochemical detection device provides a novel,easy,and low-cost platform for the separation of pure enantiomer from racemic mixture.

关键词： wood column integrated separation-detection device enantioselectivity online sensing free energy barrier

A deoxidation thermodynamic model for 304 stainless steel considering multiple-components coupled reactions

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Journal of Iron and Steel Research International 2024年第1期31卷 74-91页

作者： yan yan Guang-hao Shang Li-ping Zhang Shao-ying Li Han-jie Guo School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing100083China Beijing Key Laboratory of Special Melting and Preparation of High-End Metal Materials Beijing100083China Henan Jinhui Stainless Steel Industry Group Co. Ltd.Xuchang461500HenanChina Changge Jinhui Recycling Metal R&D Co. Ltd.Xuchang461500HenanChina

A thermodynamic model for predicting the equilibrium oxygens of 304 stainless steel was developed based on the theory of slag-steel equilibrium,the law of mass conservation,and the ion and molecule coexistence *** the developed model,the Fe-Cr-Mn-Si-Al-S-O-melts reaction system and CaO-MgO-CaF_(2)-FeO-MnO-Al_(2)O_(3)-SiO_(2)-Cr2O_(3)slags were *** oxygen contents calculated by the model are in good agreement with experimental results and reference *** equilibrium oxygen contents in 304 stainless steel mainly decrease with increasing binary basicity(w(CaO)/w(SiO_(2)),where w(i)is the mass percentage of component i)and decreasing *** binary basicity at 2.0 while maintaining temperatures lower than 1823 K will keep the oxygen contents in the 304 stainless steel lower than 15×10^(-6).The equilibrium oxygen contents may also be decreased with increasing content of MgO in slags,which is more significant at lower binary ***,a small amount of FeO,MnO,and Al_(2)O_(3)(about 0-2.5 wt.%)in slags has little effect on equilibrium oxygen ***,it is found that the[C]-[O]reaction may occur during refining process but will not significantly affect the equilibrium oxygen contents.

关键词： Complex deoxidation Thermodynamic model Ion and molecule coexistence theory 304 stainless steel Slag-steel reaction

Spherical Confinement Generates Entropic Force to Accelerate Polymer Chain Detachment

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Chinese Journal of Polymer Science 2024年第3期42卷 407-416,I0010页

作者： Yu-Shan Zheng Jian-ping Zhou yan Xu Kai Li Mechanical Engineering Xinjiang UniversityUrumqi 830002China

To understand the dynamic process of polymer detachment, it is necessary to determine the mean detachment time of a single breakable link, which is modeled as a spring. Normally, this time can be viewed as the escape of a Brownian particle from the potential well of the spring. However, as the free dangling length of the polymer chain increases, the conformational entropy of the chain is affected by geometric confinement. It means that the wall exerts a repulsive force on the chain, resulting in accelerated link detachment from a macroscopic perspective. In this work, we investigate the effect of entropy on the detachment rate in the case where the substrate is spherical. We demonstrate that spherical confinement accelerates chain detachment both inside and outside the sphere. An analytical expression for the mean detachment time of breakable links is given, which includes an additional pre-factor that is related to the partition function. Additionally, we analyze the expressions for entropic forces inside the sphere, outside the sphere, and on a flat wall, comparing their magnitudes to explain the difference in mean detachment time.

关键词： Polymer detachment Breakable link Entropic force Mean first passage time

Rotor cross-tilt optimization for yaw control improvement of multi-rotor eVTOL aircraft

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Chinese Journal of Aeronautics 2024年第3期37卷 153-167页

作者： Xufei yan Ye YUAN yanqin zhao Renliang CHEN Zhejiang Lab Hangzhou 311100China Department of Aerospace Engineering Swansea UniversitySwanseaWales SA28PPUK National Key Laboratory of Rotorcraft Aeromechanics Nanjing University of Aeronautics and AstronauticsNanjing 210016China

Manned multi-rotor electric Vertical Takeoff and Landing(eVTOL)aircraft is prone to actuator saturation due to its weak yaw control *** address this inherent problem,a rotor cross-tilt configuration is applied in this paper,with an optimization method proposed to improve the overall control efficiency of the ***,a flight dynamics model of a 500-kg manned multi-rotor eVTOL aircraft is *** accuracy of the co-axial rotor model is verified using a single arm test bench,and the accuracy of the flight dynamics model is verified by the flight test ***,an optimization method is designed based on the flight dynamics model to calculate an optimal rotor cross-tilt mounting angle,which not only improves the yaw control efficiency,but also basically maintains the efficiency of other control *** ideal rotor cross-tilt mounting angle for the prototype is determined by comprehensively considering the optimal results with different payloads,forward flight speeds,and rotor mounting angle ***,the feasibility of the rotor cross-tilt mounting angle is proved by analyzing the control derivatives of the flight dynamics model,the test data of a ground three Degree-of-Freedom(3DOF)platform,and the actual flight data of the *** results show that a fixed rotor cross-tilt mounting angle can achieve ideal yaw control effectiveness,improving yaw angle tracking and hold ability,increasing endurance time,and achieving good yaw control performance with different payloads and forward speeds.

关键词： Multi-rotor eVTOL Control efficiency Flight dynamics model Cross-tilt optimization Endurance time

Kinetic model of vibration screening for granular materials based on biological neural network

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Particuology 2024年第5期88卷 98-106页

作者： Zhan zhao yan Zhang Fang Qin Mingzhi Jin School of Agricultural Engineering Jiangsu UniversityZhenjiang212013China Shandong Academy of Agricultural Machinery Sciences Ji'nan250100China

The kinetic model is the theoretical basis for optimizing the structure and operation performance of vibration screening *** this paper,a biological neurodynamic equation and neural connections were established according to the motion and interaction properties of the material under vibration *** material feeding to the screen and the material passing through apertures were considered as excitatory and inhibitory inputs,respectively,and the generated stable neural activity landscape was used to describe the material distribution on the 2D screen *** dynamic process of material vibration screening was simulated using discrete element method(DEM).By comparing the similarity between the material distribution established using biological neural network(BNN)and that obtained using DEM simulation,the optimum coefficients of BNN model under a certain screening parameter were determined,that is,one relationship between the BNN model coefficients and the screening operation parameters was *** screening parameters were randomly selected,and the corresponding relationships were established as a ***,with straw/grain ratio,aperture diameter,inclination angle,vibration strength in normal and tangential directions as inputs,five independent adaptive neuro-fuzzy inference systems(ANFIS)were established to predict the optimum BNN model coefficients,*** training results indicated that ANFIS models had good stability and *** flexibility and adaptability of the proposed BNN method was demonstrated by modeling material distribution under complex feeding conditions such as multiple regions and non-uniform rate.

关键词： Kinetic model Material distribution Vibration screening Biological neural network DEM simulation Adaptive neuro-fuzzy inference systems

Targeting CD47-SIRPα axis for Hodgkin and non-Hodgkin lymphoma immunotherapy

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Genes & Diseases 2024年第1期11卷 205-217页

作者： Pengcheng zhao Longyan Xie Lei Yu ping Wang School of Life Sciences and Medicine Shandong University of TechnologyZiboShandong 255000China Tongji University Cancer Center Shanghai Tenth People's HospitalSchool of MedicineTongji UniversityShanghai 200092China

The interaction between cluster of differentiation 47(CD47)and signal regulatory proteinα(SiRPa)protects healthy cells from macrophage attack,which is crucial for maintain-ing immune *** of CD47 occurs widely across various tumor cell types and transmits the"don't eat me"signal to macrophages to avoid phagocytosis through binding to *** of the CD47-SIRPa axis is therefore a promising approach for cancer *** is the most common hematological malignancy and is an area of unmet clin-ical *** review mainly described the current strategies targeting the CD47-SIRPa axis,including antibodies,SiRPaFc fusion proteins,small molecule inhibitors,and peptides both in preclinical studies and clinical trials with Hodgkin lymphoma and non-Hodgkin lymphoma.

关键词： Cancer treatment CD47-SIRPαaxis Hodgkin lymphoma Immunotherapy Non-Hodgkin lymphoma

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基于EAST装置上液态调配器系统的研究

原子能科学技术 2008年第8期42卷 760-764页

作者：王磊赵燕平中国科学院等离子体物理研究所安徽合肥230031

液态调配器是用于离子回旋共振加热系统以代替传统活塞式调配器的一种新型阻抗匹配装置。通过对液态调配器工作原理的研究,设计了液态调配器的油路系统,采用计算机和可编程控制器对系统进行控制。同时,对液态调配器各支节匹配高度的计... 详细信息

液态调配器是用于离子回旋共振加热系统以代替传统活塞式调配器的一种新型阻抗匹配装置。通过对液态调配器工作原理的研究,设计了液态调配器的油路系统,采用计算机和可编程控制器对系统进行控制。同时,对液态调配器各支节匹配高度的计算方法进行了研究,提出了计算公式,并利用实验中测得的数据对计算公式进行了验证。经过两轮EAST实验使用证实,该系统完全满足设计要求。

关键词：液态调配器可编程控制器阻抗匹配

基于社会网络分析的E-mail内容安全动态监测模型

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北京理工大学学报 2006年第Z1期26卷 79-83页

作者：李玮赵燕平北京理工大学管理与经济学院北京100081 北京理工大学管理与经济学院北京100081

为减少有害信息的传播,运用白名单、黑名单、主题词和关键词多种过滤方法,将社会网络分析技术引入E-mail信息安全领域,提出一种基于社会网络分析的E-mail内容安全动态监测模型.通过分析被过滤出的人员构成的信息传递网络,社会网络分析... 详细信息

为减少有害信息的传播,运用白名单、黑名单、主题词和关键词多种过滤方法,将社会网络分析技术引入E-mail信息安全领域,提出一种基于社会网络分析的E-mail内容安全动态监测模型.通过分析被过滤出的人员构成的信息传递网络,社会网络分析技术可以辅助安全调查人员把表面毫无联系的邮件信息内容关联起来,从而确定相关人员之间的联系,动态识别网络组织构成,并可以发现骨干网络及其中心人物,以便对其进行有效监控.

关键词：电子邮件内容安全社会网络分析