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high power Laser Science and Engineering 2024年第3期12卷 134-145页

作者： M.Füle A.p.Kovács t.Gilinger M.Karnok p.Gaál S.Figul G.Marowsky K.Osvay National Laser-Initiated transmutation Laboratory University of SzegedSzegedHungary Department of Experimental physics University of SzegedSzegedHungary ELI ALpS ELI-HU Non-Profit Ltd.SzegedHungary Department of Optics and Quantum Electronics University of SzegedSzegedHungary Advanced Microfluidic Systems Gmbh GöttingenGermany

A colliding microjet liquid sheet target system was developed and tested for pairs of round nozzles of 10,11 and 18μm in *** sheet's position stability was found to be better than a few *** interaction with 50 mJ laser pulses,the 18μm jet has a resonance amplitude of 16μm at a repetition rate of 33 hz,while towards 100 hz it converges to 10μm for all nozzles.A white-light interferometric system was developed to measure the liquid sheet thickness in the target chamber both in air and in vacuum,with a measurement range of 182 nm±1μm and an accuracy of±3%.the overall shape and 3D shape of the sheet follow the hasson±peck model in *** vacuum versus air,the sheet gradually loses 10%of its thickness,so the thinnest sheet achieved was below 200 nm at a vacuum level of 10±4mbar,and remained stable for several hours of operation.

关键词： diagnostics laser ion acceleration nanometric liquid sheet targets vacuum test

INVEStIGAtION OF UNStEADY EXCItAtION EFFECtS ON AERODYNAMIC pROpERtIES OF AIRFOILS

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Chinese Journal of Aeronautics 1991年第2期6卷 163-170页

作者： Cui E J, Fu G M Yu X t Beijing Institute of Aerodynamics p.O. Box 7215, Beijing, China

In this paper, the techniques to manage and control the flow over airfoils by using the external unsteady excitations are investigated. the mechanisms of these excitation effects are also explored. the principal goal of this study is to gain a better understanding and to find the possible ways for enhancing the aerodynamic efficients. the experimental investigations are carried out in two low-speed wind tunnels. the test models are two dimensional airfoils with different section geometries. Four means of excitations have been used in these experiments. (1) the pitch oscillation of the airfoil high-angle-of-attack situation. (2) the moving surface effects of the airfoil with a leading edge rotating cylinder. (3) Oscillating leading edge flaperon. (4) Small oscillating spoiler located near the leading edge of the airfoil. the lift, drag and pitch moment coefficients are measured in these experiments. But, we will put the emphasis only on the 'dynamic amplifying effects' on aerodynamic lift in this paper. Results obtained indicate that the beneficial aerodynamic effects of section lift increase can be obtained at the high angle of attack near stall regime, as long as the frequency and amplitute of the excitation are appropriately selected.

关键词： INVEStIGAtION OF UNStEADY EXCItAtION EFFECtS ON AERODYNAMIC pROpERtIES OF AIRFOILS high Flow body

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城市垃圾的高固体浓度发酵试验及其农业利用

农业现代化研究 1989年第5期10卷 37-39页

作者：刘克鑫 t.h.Chen DavidF.Chynoweth 中国科学院成都生物研究所美国佛罗里达大学农业工程系

城市垃圾是一大公害。采用厌氧堆肥法处理垃圾,回收能源,已越来越受到重视。但常规厌氧堆肥法尚有一些缺点,特别是含水量太高,不便处理和运输。本研究是探讨40～50％tS浓度下发酵的可行性。结果表明:在tS浓度为20～50％的情况下,能正常... 详细信息

城市垃圾是一大公害。采用厌氧堆肥法处理垃圾,回收能源,已越来越受到重视。但常规厌氧堆肥法尚有一些缺点,特别是含水量太高,不便处理和运输。本研究是探讨40～50％tS浓度下发酵的可行性。结果表明:在tS浓度为20～50％的情况下,能正常产出Ch_4。最终ph值和挥发酸浓度都属正常范围。随着tS浓度的增高Ch_4量逐渐降低。在20～40％tS浓度范围内降低幅度不大。在tS浓度为50％时,产Ch_4量大大降低。tS和VS的生物降解量与产Ch_4量基本一致。

关键词：城市垃圾处理综合利用农业

XAFS Study on Solid State Amorphization of Alloys by Mechanical Alloying

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中国科学技术大学学报 2001年第3期31卷 261-267页

作者： Nasu,t Sakurai,M FacultyofEducation YamagataUniversityYamagata990－8560Japan InstituteforMaterialsResearch TohokuUnive

Structural evolution of alloys by ball milling during solid state amorphization were studied by means of XAFS technique. the first one is amorphization process of Fe and B powder mixtures by mechanical alloying (MA), and the second one is amorphization process of ordered B2 CoZr intermetallic compound by mechanical milling (MM). the mixing process of Fe and B and disintegration process of ordered B2 CoZr intermetallic compound crystal were observed clearly in atomic level by XAFS method. the micro mechanism of amorphization process of alloy by ball milling was discussed.

关键词： XAFS方法机械合金化固态非晶化反应机理

Improved thermal performance of a hydronic radiant panel heating system by the optimization of tube shapes

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Journal of Zhejiang University-Science A(Applied physics & Engineering) 2011年第6期12卷 428-437页

作者： Young t.ChAE Kwang ho LEE Jae Sung pARK School of Architecture University of Illinois at Urbana-Champaign Department of Architectural Engineering Hanbat National University Department of Mechanical Engineering University of Illinois at Urbana-Champaign

the thermal performance enhancement of the hydronic radiant floor heating system by tube shape refinements is investigated in this *** analytical and detailed numerical modelings are carried out to predict the performance of the radiant *** the simple analytical model briefly investigates the possibility of the effect of the tube shape improvement with the parametric analysis,the commercial computational fluid dynamics(CFD) code(Ansys/CFX) is used to perform the detailed 3D analysis under different tube shape *** fin thickness,the number of fins,and the tube thermal conductivity turn out to have significant effects on the radiant system *** potential energy saving impacts of the tube shape refinements are also *** tube shape improvement turns out to increase the floor surface temperature and to decrease the hot water temperature drop across the system,resulting in heating energy savings.

关键词： Radiant panel system Analytical modeling Computational fluid dynamics(CFD) tube shape Energy saving

Estimation of Inverse Autocovariance Matrices for Long Memory processes

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Estimation of Inverse Autocovariance Matrices for Long Memor...

第十届海峡两岸统计与概率研讨会

作者： C.-K.Ing h.-t.Chiou M.h.Guo “Academia Sinica” “National Sun Yat-sen University”

this work aims at estimating inverse autocovariance matrices of longmemory processes. A modified Cholesky decomposition is used inconjunction with an increasing order autoregressive model to achievethis goal. the spectral norm consistency of the proposed estimate is established. We then extend this result to linear regression models withlong-memory time series errors. In particular, we show that when the objective is to consistently estimate the inverse autocovariance matrix of the error process, the same approach still works well if the estimated(by least squares) errors are used in place of the unobservable ones. Finally, a simulation study is performed to illustrate our theoretical findings.

关键词： inverse autocovariance matrix linear regression model long memory process modified Cholesky decomposition

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硅反型层中热功率的磁量子振荡

Journal of Semiconductors 1993年第10期14卷 597-604页

作者：秦国毅 p.N.Butcher t.M.Fromhold 半导体超晶格国家重点实验室 Department of physics Warwick UniversityCoventry CV4 7ALUK

本文把Butcher等提出的计算GaAs异质结磁热功率振荡的理论方法推广用于计算硅反型层的磁热功率。计算中同时计及了磁热功率张量的屏蔽声曳贡献和扩散贡献,采用了重新核实的硅反型层二维电子密度数据,并用电阻张量的实验值取代有较大误... 详细信息

本文把Butcher等提出的计算GaAs异质结磁热功率振荡的理论方法推广用于计算硅反型层的磁热功率。计算中同时计及了磁热功率张量的屏蔽声曳贡献和扩散贡献,采用了重新核实的硅反型层二维电子密度数据,并用电阻张量的实验值取代有较大误差的解析公式。计算结果远优于前人的结果,在振荡位相和幅度两方面都与Oxley等提供的t=5.020K下的最新实验数据定性相符。

关键词：硅反型层热功率量子振荡

Optoelectronic properties of pure and Co Doped Indium Oxide by hubbard and modified Becke–Johnson Exchange potentials

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Chinese physics Letters 2013年第12期30卷 107-111页

作者： h.A.Rahnamaye Aliabad M.Bazrafshan h.Vaezi Masood Yousaf Junaid Munir M.A.Saeed Department of physics Hakim Sabzevari UniversitySabzevarIran Department of physics Khayyam Institute of Higher EducationMashhadIran Department of physics Universiti Teknologi MalaysiaSkudai 81310JohorMalaysia

Structural and optoelectronic properties of pure and Co doped In2O3 are studied by employing the full-potential linearized augmented plane wave method,which is known to produce highly accurate *** principles calculations are performed with ordinary generalized gradient approximation(GGA)along with new hubbard and modified Becke-Johnson exchange(mBJ)potential *** band gap results are obtained for In2O3 with GGA+U and *** the case of mBJ,the band gap values are 3.5 eV and 3.4 eV for rhombohedral and cubic phases,which are in close agreement with the experimental *** of In by Co 25%alters the energy gap and a spin splitting effect is observed in these *** the spin-up state,it remains semiconductor,whereas for the spin-down state it shows semimetallic *** value of static refractive index n(0)is 1.74 for the cubic phase,while in rhombohedral phase the values of n(0)are 1.77 and 1.74 along xx and zz optical axes,*** calculated optical properties conform anisotropy in the rhombohedral phase and these materials can be potential candidates for the optoelectronics applications.

关键词： behavior hubbard cubic

Susceptibility of Large Wind power plants to Voltage Disturbances-Recommendations to Stakeholders

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Journal of Modern power Systems and Clean Energy 2022年第2期10卷 416-429页

作者： Roger Alves de Oliveira Math h.J.Bollen the Electric power Engineering Group Lulea University of TechnologySkellefteaSweden

Sufficient fault ride-through(FRt)of large wind power plants(Wpps)is essential for the operation security of transmission *** majority of studies on FRt do not include all disturbances originating in the transmission system or the disturbances irrelevant to the operation *** on the knowledge of power quality,this paper provides a guide to stakeholders in different aspects of FRt for wind turbines(Wts)and *** paper details the characteristics of the most common disturbances originated in the transmission system,how they propagate to the Wt terminals,and how they impact the dynamic behavior of a large *** paper shows that the details of the voltage disturbances,not only in the transmission system,but also at the Wt terminals,should be taken into ***,a detailed representation or characterization of voltage dips is important for FRt studies,despite that the simplified models used in the literature are *** paper strongly recommends that distinct events and additional characteristics such as the phase-angle jump and oscillations in the transition segments should be considered in FRt analysis.

关键词： Wind power generation wind farm power quality fault ride-through(FRt) low voltage ride-through(LVRt)