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Y-Ba-Cu-O mixed oxides for production of diphenols in liquid-solid phase

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Chinese Journal of Chemistry 1996年第6期14卷 516-524页

作者： Liu, CB zhao, z Yang, XG Ye, XK wu, Y CHINESE ACAD SCI CHANGCHUN INST APPL CHEMCHANGCHUN 130022JILINPEOPLES R CHINA

Superconductor mixed oxides were often used as catalysts at higher temperature in gas phase oxidations, and considered not suitable for lower temperature reactions in the liquid-solid phase; here the catalysis of YBa2Cu3O7+/-x and Y2BaCuO5+/-x in the phenol hydroxylation at lower temperature with H2O2 as oxygen donor was studied, and found that the superconductor YBa2Cu3O7+/-x, has no catalytic activity for phenol hydroxylation, but Y2BaCuO5+/-x does, even has better catalytic activity and stability than most previously reported ones. With the studies of catalysis of other simple metal oxides and perovskite-like mixed oxides, a radical substitution mechanism is proposed and the experimental facts are explained clearly, and draw a conclusion that the perovskite-like mixed oxides with (AO)(ABO(3)) and (AO)2(ABO(3)) structure have better catalytic activity than the simple perovskite oxides with (ABO(3))(3) structure alone, and (AO) structure unit is the key for the mixed oxides to have the phenol hydroxylation activity. No pollution of this process is very important for its further industrial application.

关键词： superconductor mixed oxides phenol hydroxylation radical substitution

On a general theory for compressing process and aeroacoustics:linear analysis

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Acta mechanica Sinica 2010年第3期26卷 355-364页

作者： E .mao Y. P. Shi J. z. wu State Key Laboratory for Turbulence and Complex Systems College of Engineering Peking University 100871 Beijing China University of Tennessee Space Institute Tullahoma TN 37388 USA

Of the three mutually coupled fundamental processes （shearing, compressing, and thermal） in a general fluid motion, only the general formulation for the compress- ing process and a subprocess of it, the subject of aeroacous- tics, as well as their physical coupling with shearing and thermal processes, have so far not reached a consensus. This situation has caused difficulties for various in-depth complex multiprocess flow diagnosis, optimal configuration design, and flow/noise control. As the first step toward the desired formulation in fully nonlinear regime, this paper employs the operator factorization method to revisit the analytic linear theories of the fundamental processes and their decomposi- tion, especially the further splitting of compressing process into acoustic and entropy modes, developed in 1940s-1980s. The flow treated here is small disturbances of a compressible, viscous, and heat-conducting polytropic gas in an unbounded domain with arbitrary source of mass, external body force, and heat addition. Previous results are thereby revised and extended to a complete and unified theory. The theory pro- vides a necessary basis and valuable guidance for developing corresponding nonlinear theory by clarifying certain basic issues, such as the proper choice of characteristic variables of compressing process and the feature of their governing equations.

关键词： Longitudinal (compressing) processTransversal (shearing) process Acoustic mode Entropy mode Aeroacoustics

Transmission Electron microscopy Study of the Infrared Brazed High-strength Titanium Alloy

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Journal of materials Science & Technology 2010年第4期26卷 311-316页

作者： z.Y. wu R.K. Shiue C.S. Chang Department of materials Science and Engineering National Taiwan University Taipei 106 Taiwan China Engineered materials Solutions 39 Perry Avenue MS 4-1 Attleboro MA 02703-2410 USA

The transmission electron microscopy was employed to investigate the microstructure of infrared brazed highstrength Ti alloy using the Ti-15Cu-15Ni filler metal. Coarse primary Ti2Ni and transformed β-Ti are observed in the 300 s brazed specimen. Blocky Ti2Ni and eutectoid Ti2Cu intermetallics are disappeared from the joint with increasing the brazing time to 1800 s. Both acicular α-Ti and retained β-Ti dominate the entire brazed joint.

关键词： Infrared Brazing Ti Ti-Cu-Ni filler microstructure

The cGAS-STING-interferon regulatory factor 7 pathway regulates neuroinflammation in Parkinson's disease

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Neural Regeneration Research 2025年第8期20卷 2361-2372页

作者： Shengyang zhou Ting Li Wei zhang Jian wu Hui Hong Wei Quan Xinyu Qiao Chun Cui Chenmeng Qiao Weijiang zhao Yanqin Shen Laboratory of Neurodegenerative and Neuroinjury Diseases Wuxi Medicine SchoolJiangnan UniversityWuxiJiangsu ProvinceChina

Interferon regulatory factor 7 plays a crucial role in the innate immune ***,whether interferon regulatory factor 7-mediated signaling contributes to Parkinson's disease remains *** we report that interferon regulatory factor 7 is markedly up-regulated in a 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-induced mouse model of Parkinson's disease and co-localizes with microglial *** the selective cyclic guanosine monophosphate adenosine monophosphate synthase inhibitor RU.521 and the stimulator of interferon genes inhibitor H151 effectively suppressed interferon regulatory factor 7 activation in BV2 microglia exposed to 1-methyl-4-phenylpyridinium and inhibited transformation of mouse BV2 microglia into the neurotoxic m1 *** addition,si RNA-mediated knockdown of interferon regulatory factor 7 expression in BV2 microglia reduced the expression of inducible nitric oxide synthase,tumor necrosis factorα,CD16,CD32,and CD86 and increased the expression of the anti-inflammatory markers ARG1 and *** together,our findings indicate that the cyclic guanosine monophosphate adenosine monophosphate synthase-stimulator of interferon genes-interferon regulatory factor 7 pathway plays a crucial role in the pathogenesis of Parkinson's disease.

关键词： cyclic guanosine monophosphate adenosine monophosphate synthase H151 interferon regulatory factor 7 m1 phenotype neurodegenerative disease neuroinflammation Parkinson’s disease RU521 STING type I interferon

A theoretical study on different cluster configurations of the ~9Be nucleus by using a simple cluster model

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Nuclear Science and Techniques 2017年第6期28卷 179-189页

作者： m.Aygun z.Aygun Department of Physics Bitlis Eren University Vocational School of Technical Sciences Bitlis Eren University

In this study,a comprehensive investigation on different cluster configurations of the ~9Be nucleus is performed with a simple cluster *** this goal,the elastic scattering angular distributions of ~9Be by ^(27)A1,^(28)Si,^(64)zn,^(144)Sm,^(208)Pb,and ^(209)Bi target nuclei are reanalyzed for α + α + n,d + ~7Li,~3H + ~6Li,~3He + ~6He and n + ~8Be cluster configurations of the ~9Be projectile within the framework of the optical *** theoretical results are compared with each other as well as the experimental *** results provide an opportunity for a test of different cluster configurations in explaining the elastic scattering of^9Be nucleus.

关键词： Cluster structure Optical model Double folding model Elastic scattering

Exergy analysis of R1234ze（z） as high temperature heat pump working fluid with multi-stage compression

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Frontiers in Energy 2017年第4期11卷 493-502页

作者： Bin HU Di wu L.W. WANG R.z. WANG Institute of Refrigeration and Cryogenics Shanghai Jiao Tong University Shanghai 200240 China

In this paper, the simulation approach and exergy analysis of multi-stage compression high tempera- ture heat pump （HTHP） systems with R1234ze（z） working fluid are conducted. Both the single-stage and multi-stage compression cycles are analyzed to compare the system performance with 120℃ pressurized hot water supply based upon waste heat recovery. The exergy destruction ratios of each component for different stage compression systems are compared. The results show that the exergy loss ratios of the compressor are bigger than that of the evaporator and the condenser for the single-stage compres- sion system. The multi-stage compression system has better energy and exergy etticiencies with the increase of compression stage number. Compared with the single- stage compression system, the coefficient of performance （COP） improvements of the two-stage and three-stage compression system are 9.1% and 14.6%, respectively. When the waste heat source temperature is 60℃, the exergy efficiencies increase about 6.9% and 11.8% for the two-stage and three-stage compression system respec- tively.

关键词： multi-stage compression high temperatureheat pump heat recovery exergy destruction,R1234ze(z) working fluid

RESEARCH ON mEASURING mETHOD OF THE THERmALCONDUCTIVITY FOR HIGHLY POROUS mATERIALS

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Acta metallurgica Sinica(English Letters) 1997年第3期10卷 213-218页

作者： J Y wu z.m. Tang W Shi andR.z. Wang (Institute of Refrigeration and Cryogenics Engineering, Shanghai Jiao Tong University, Shanghai 200030,China) Shanghai Jiaotong Univ Shanghai China

A transient method with rectangular pulse heating has been developed to measure the thermal conductivity of highly porous materials such as activated carbon, zeolite and silica gel. By this method the thermal conductivity can be measured quickly and accu-rately. In this paper, a set of automatically controlled testing equiptnent is *** measuring method is analysed. The thermal conductivities of some samples, such as activated carbon and zeolite, are measured by the equipment. A group of useful data has been obtained.

关键词： thermal conductivity porous material thermophysical property

A betatron tune measurement system based on bunch-by-bunch transverse feedback at the Duke storage ring

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Chinese Physics C 2013年第7期37卷 76-82页

作者：徐卫 W. z. wu 李京祎何多慧 Y. K. wu National Synchrotron Radiation Laboratory (NSRL) University of Science and Technology of China FEL Laboratory TUNL and Department of Physics Duke University

To combat electron beam instabilities, a digital bunch-by-bunch transverse feedback （TFB） system has been developed for the Duke storage ring. While it is capable of suppressing transverse beam instabilities for multibunch operation, the TFB system has not been needed for typical operation of the Duke storage ring. To explore the great potential of this system, we have developed beam diagnostic techniques using the TFB, in particular, the TFB based tune measurement techniques. The tune measurement technique allows us to conduct fast chromaticity measurements, compared with the existing chromaticity measurement system using a network analyzer. This new tune measurement system also enables us to measure the bunch tune for multibunch operation of the Duke storage ring. With the TFB based tune measurement system, we have studied the tune stability of the electron beam in the Duke storage ring. This tune system has also been used to calibrate the tune knob for the Duke storage ring.

关键词： transverse feedback tune chromaticity

Asymmetrical Fault Current Calculation method and Influencing Factors Analysis of Droop-Controlled Inverters

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 562-573页

作者： Huimin zhao zhikang Shuai Jun Ge An Luo Weimin wu z.John Shen College of Electrical and Information Engineering Hunan UniversityChangsha 410006China Electrical Engineering Department Shanghai Maritime UniversityShanghai 201306China Department of Electrical and Computer Engineering Ilinois Institute of TechnologyChicagoIL 60616 USA

Since the fault dynamic of droop-controlled inverter is different from synchronous generators (SGs), protection devices may become invalid, and the fault overcurrent may damage power electronic devices and threaten the safety of the microgrid. Therefore, it is imperative to conduct a comprehensive fault analysis of the inverter to guide the design of protection schemes. However, due to the complexity of droop control strategy, existing literatures have simplified asymmetric fault analysis of droop-controlled inverters to varying degrees. Therefore, accurate fault analysis of a droop-controlled inverter is needed. In this paper, by analyzing the control system, an accurate fault model is established. Based on this, a calculation method for instantaneous asymmetrical fault current is proposed. In addition, the current components and current characteristics are analyzed. It was determined that fault currents are affected by control loops, fault types, fault distance and nonlinear limiters. In particular, the influences of limiters on the fault model, fault current calculation and fault current characteristics were analyzed. Through detailed analysis, it was found that dynamics of the control loop cannot be ignored, the fault type and fault distance determine fault current level, and part of the limiters will totally change the fault current trend. Finally, calculation and experimental results verify the correctness of the proposed method.

关键词： Asymmetrical fault analysis droop control fault current calculation method limiter transient fault characteristics