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Automatic and Rapid Throughflow-Based Optimal Design Method for Multi-Stage Axial-Flow compressors

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Journal of Thermal Science 2025年第1期34卷 77-91页

作者： LEI Fan ZHANG Xiawen JU Yaping ZHANG Chuhua Department of Fluid Machinery and Engineering School of Energy and Power EngineeringXi'an Jiaotong University Production and Environmental Department China Huaneng Group.Co.Ltd. State Key Laboratory for Strength and Vibration of Mechanical Structures Xi'an Jiaotong University

Throughflow design has the advantages of less time consumption and large optimization space,and thus is the corner stone of advanced design system of multi-stage axial-flow *** majority of relevant studies were limited to the throughflow inverse designs,and quite few works have been till now devoted to the throughflow optimal *** this work,an automatic and rapid throughflow-based optimal design method is proposed for axial-flow compressors in which a throughflow inverse design solver is embedded in optimal genetic algorithm to improve the design efficiency of axial-flow *** types of design parameters in the throughflow inverse design of axial-flow compressors,i.e.,swirl and shroud curve,are simultaneously used to optimize both the blade shape and flow *** proposed method is validated by the redesign optimization of the benchmark axial-flow compressor NASA Stage 35,and the CFD predictions show that the throughflow-based optimization leads to 1.18% efficiency benefit at design *** proposed method is then utilized to the two-dimensional throughflow optimal design of a large-scale 6.5-stage axial-flow industrial *** optimal design results are confirmed by CFD predictions,indicating that the proposed method can effectively improve the design adiabatic efficiency of the compressors by 1.09% within a few minutes on desk-top *** throughflow design implications are also obtained for advanced axial-flow industrial *** work could enhance the capability of throughflow design method and has engineering application value to explore the throughflow optimization space of multi-stage axial-flow compressors.

关键词： NASA

Real-time displacement measurement with large range and high accuracy using sinusoidal phase modulating laser diode interferometer

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Chinese Optics Letters 2007年第4期5卷 211-214页

作者：何国田王向朝曾爱军唐锋黄炳杰 Shanghai Institute of Optics and fine Mechanics Chinese Academy of Sciences Shanghai Hengyi Optics & fine Mechanics co. ltd.

To resolve the conflict of large measurement range and high accuracy in the existing real-time displacement measurement laser diode （LD） interferometers, a novel real-time displacement measurement LD interferometry is proposed and its measurement principle is analyzed. By use of a new phase demodulation algorithm and a new phase compensation algorithm of real-time phase unwrapping, the measurement accuracy is improved, and the measurement range is enlarged to a few wavelengths. In experiments, the peak-to-peak amplitude of the speaker vibration was 2361.7 nm, and the repeatability was 2.56 nm. The measurement time was less than 26 us.

关键词： Algorithms Interferometers Semiconductor lasers

Effects of Ti-and Nb-based transition element from single to multiple compound oxides and carbon-based composite additives on Mg-MgH2 hydrogen storage material

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Tungsten 2025年第1期7卷 32-49页

作者： Li-Rong Xiao Chen Chen Shuo Wang Zi-Yin Dai Hideo Kimura Cui Ni Chuan-Xin Hou Xue-Qin Sun Si-Jie Guo Wei Du Xiu-Bo Xie School of Environmental and Material Engineering Yantai University Bosch HUAYU Steering Systems (Yantai) co. Ltd.Ytp/MFE University of Tennessee Knoxville Shandong Key Laboratory of Eco-Environmental Science for the Yellow River Delta Shandong University of Aeronautics

MgH2is considered as a promising hydrogen storage material for its high hydrogen storage capacity,low cost and abundant resource ***,the low kinetics and high enthalpy formation of MgH2limit its wide *** the perspective of adding catalysts to enhance the hydrogen storage properties of Mg-MgH2,this article elaborated the main catalysts based on Ti and Nb transition elements,including single oxide catalysts,binary oxides catalysts（combined with Ni,Na,Sr,V,etc.）,multiple catalysts bound to carbon,and composite catalysts with Ti and Nb elements combined with MXene ***,the main pathways of various catalysts to reduce the reaction activity and broaden the hydrogen desorption channel were also *** Ti-based catalysts can enhance the reactive sites of the matrix by forming multivalent states,while Nb-based catalysts broaden the hydrogen reaction channels by forming tiny *** improving the size structure and enhancing the grain size stability,combined with carbon materials should be the future considerations.

关键词： Catalysts Mg-based hydrogen storage alloys Solid hydrogen storage Transition metal elements

Molecular Mechanism and Molecular Design of Lubricating Oil Antioxidants

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China Petroleum Processing & Petrochemical Technology 2024年第2期26卷 135-145页

作者： Su Shuo Long Jun Duan Qinghua Zhou Han Zhao Yi SINOPEC Research Institute of Petroleum Processing co.ltd. Beijing 100083

To overcome the limitations of traditional experimental“trial and error”methods in lubricant additive design,a new molecular design method based on molecular structure parameters is established *** molecular mechanism of the antioxidant reaction of hindered phenol,diphenylamine,and alkyl sulfide are studied via molecular *** results show that the strong electron-donating ability and high hydrogen-donating activity of the antioxidant molecule and the low hydrogen-abstracting activity of free radicals formed after dehydrogenation are the internal molecular causes of the shielding of phenol and diphenylamine from scavenging peroxy free radicals,and the strong electron-donating ability is the internal molecular cause of the high activity of thioether in decomposing alkyl hydrogen *** on this antioxidant molecular mechanism,a molecular design rule of antioxidant is proposed,namely“high EHOMO,large Q(S),low bond dissociation energy BDE(O—H)and BDE(N—H)”.Two new antioxidants,PAS-I and PAS-II,are designed and prepared by chemical bonding of hindered phenol,diphenylamine,and sulfur *** results show that these antioxidants both have excellent antioxidant effects in lubricating oil,and that PAS-II is the superior antioxidant,consistent with theoretical predictions.

关键词： lubricating oil antioxidant molecular mechanism molecular design antioxidant performance

Small-diameter vertical shafts constructed in the shallow space of steep mountainous areas

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Underground Space 2019年第3期4卷 235-250页

作者： T.Hara A.Yashima K.Sawada K.Kariya H.Tsuji N.Soga University of Toyama Japan Gifu University Japan Eight Kogyo co.ltd. Japan

Japan is a mountainous country comprising several islands,in which mountains occupy 70%of the entire ***,numerous transmission line towers have been constructed in the shallow space of steep mountainous *** such construction,monorails and/or cableways are generally used to transport materials and equipment to the construction site instead of using a construction road,as the former method is more economically ***,with this method,drill rigs or vertical shaft sinking machines cannot be transported to the *** small-diameter vertical shafts of 2.5 or 3.0 m as the foundation for high-voltage transmission line towers in mountainous areas are traditionally constructed manually in *** the past two decades,however,dangerous and poor environmental conditions for workers regarding the manual construction of these small-diameter vertical shafts have become a major ***,owing to the poor environmental conditions of small-diameter vertical shafts to be constructed in the shallow space of steep mountainous areas,a decrease has occurred in the number of young workers entering these ***,the construction of transmission line towers with using the manually traditional small-diameter vertical shafts is becoming difficult in Japan from abovementioned *** development of a new technology to solve the problems is necessary for Japan’s economic *** this knowledge,the authors have developed a new small-diameter vertical shaft construction system,in which workers do not have to enter the vertical shaft during construction,as machines are used *** applicability of the proposed system was confirmed by means of the construction of three actual vertical shafts at two construction sites,as well as in factory and field *** applicability and details of the final proposed system are summarized in this paper.

关键词： Small-diameter vertical shaft Shallow space Steep mountainous area

Effect of cyclic heat treatment on microstructure and mechanical properties of 50CrV4 steel

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Journal of Central South University 2015年第2期22卷 409-415页

作者：李红英韩茂盛李德望李俊徐德超 School of Materials Science and Engineering Central South University Research Institute Baoshan Iron & Steel co.ltd.

An annealed 50 Cr V4 steel was subjected to cyclic heat treatment process that consists of repeated short-duration(200 s)held at 840 °C(above Ac3 temperature of 790 °C) and short-duration(100 s) held at 700 °C(below Ac1 temperature of 710 °C). The spheroidization ratio of cementite and the average size of particles increase with increasing the cyclic number of heat treatment. After5-cycle heat treatment, the spheroidization ratio of cementite is 100%, and the average size of the cementite particles is about0.53 μm. After cyclic heat treatment, the hardness, ultimate tensile strength and yield strength of the experimental steel gradually decrease with increasing cyclic number of heat treatment. The elongation of the as-received specimens is about 7.4%, the elongation of the 1-cycle specimen is 14.3%, and the elongation of 5-cycle specimen reaches a peak value of 22.5%, thereafter marginally decreases to 18.3% after 6-cycle heat treatment. Accordingly, the fractured surface initially exhibits the regions of wavy lamellar fracture. By increasing the cyclic number of heat treatment cycles, the regions of dimples consume the entire fractured surface gradually. Some large dimples can be found in the fracture surface of the specimen subjected to six heat treatment cycles.

关键词： cyclic heat treatment accelerated spheroidization mechanical properties

Sinusoidal phase-modulating laser diode interferometer for real-time surface profile measurement

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Chinese Optics Letters 2007年第3期5卷 164-167页

作者：何国田王向朝曾爱军唐锋 Shanghai Institute of Optics and fine Mechanics Chinese Academy of Sciences Shanghai Hengyi Optics & fine Mechanics co. ltd.

A sinusoidal phase-modulating （SPM） laser diode （LD） interferometer for real-time surface profile measurement is proposed and its principle is analyzed. The phase signal of the surface profile is detected from the sinusoidal phase-modulating interference signal using a real-time phase detection circuit. For 60 × 60 measurement points of the surface profile, the measuring time is 10 ms. A root mean square （RMS） measurement repeatability of 3.93 nm is realized, and the measurement resolution reaches 0.19 nm.

关键词： Interferometers Phase modulation Real time systems Semiconductor lasers Signal detection

Real-time measurement of the fast axis angle of a quarter-wave plate based on simultaneous phase shifting technique

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Chinese Optics Letters 2008年第8期6卷 568-571页

作者：杨坤曾爱军王向朝王华唐锋 Shanghai Institute of Optics and fine Mechanics Chinese Academy of Sciences Shanghai Hengyi Optics and fine Mechanics co. Ltd.

Real-time measurement of the fast axis angle of a quarter-wave plate based on simultaneous phase shifting technique is presented. The simultaneous phase shifting function is realized by an orthogonal grating, a diaphragm, an analyzer array, and a 4-quadrant detector. The intensities of the light beams from the four analyzers with different azimuths are measured simultaneously. The fast axis angle of the quarter-wave plate is obtained through the four light intensity values. In this method, rotating elements are not required, so real-time measurement is achieved.

关键词： Electromagnetic waves

Single-shot grating-based x-ray differential phase contrast imaging with a modified analyzer grating

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Chinese Physics B 2017年第10期26卷 501-507页

作者：卫晨希吴朝 Faiz Wali 魏文彬鲍园骆荣辉王磊刘刚田扬超 National Synchrotron Radiation Laboratory University of Science and Technology of China Shanghai United Imaging Healthcare co.ltd.

X-ray grating interferometer has attracted widely attention in the past years due to its capability in achieving x-ray phase contrast imaging with low brilliance source. However, the widely used phase stepping information extraction method reduces system stability and prolongs data acquisition time by several times compared with conventional x-ray absorption- based imaging. The mechanical stepping can be avoided by using a staggered grating, but at the cost of low vertical spatial resolution. In this paper, employing a modified staggered grating and the angular signal radiography, we proposed a single-shot grating-based x-ray differential phase contrast imaging with decent vertical spatial resolution. The theoretical framework was deduced and proved by numerical experiments. Absorption, phase, and scattering computed tomography can be performed without phase stepping. Therefore, we believe this fast and highly stable imaging method with decent resolution would be widely applied in x-ray grating-based phase contrast imaging.

关键词： x-ray phase contrast imaging single-shot decent resolution staggered grating computed tomography