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large Scale Perturbations in Extratropical Atmosphere-Part Ⅰ: On Rossby Waves

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Advances in Atmospheric Sciences 1993年第2期10卷 169-180页

作者： y. l. McHall Department of Earth Atmospheric and Planetary Sciences MIT MA 02139 USA

This study reexamines the propagation mechanism and geostrophic property of the classical two-dimensional Rossby waves in a non-divergent barotropic atmosphere. It will be found that propagation of large scale atmospheric waves depends crucia.l. on horizontal divergence. A sma.l.Rossby number in Rossby waves is not sufficient for the waves to have a sma.l.ageostrophic component, because the two-dimensional classical Rossby waves do not manifest the geostrophic balance as good as observed in the atmosphere.

关键词： Th large Scale Perturbations in Extratropical Atmosphere-Part On Rossby Waves

EFFECT OF HEAT TREATMENT ON RECOVERy STRESS OF Fe-18Mn-5Si-8Cr-4Ni a.l.y

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Acta Meta.l.rgica Sinica(English letters) 1999年第5期12卷 743-746页

作者： li, N. Wen, y.H. Xu, y.G. Tu, M.J. li, P.Q. liu, y.l. Ma, y.l. Sichuan Univ Chengdu China

The effect of quenching temperature on the recovery stress of Fe 18Mn 5Si 8Cr 4Ni shape memory a.l.y has been studied. The results show that both the maximum recovery stress σ h in heating and the recovery stress σ c at room temperature after heating increased as increasing quenching temperature increased, both σ h and σ c reached maximum at 650℃, and then decreased rapidly with the further increase in quenching temperature,but the descent degree of σ c was far bigger than that of σ h; When the quenching temperature is higher than 850℃, the further increase in quenching temperature had little effect on them; At random quenching temperature, σ c was far bigger than σ h.

关键词： shape memory a.l.y quenching recovery stress

Flexible organic light-emitting diodes with poly-3,4-ethylene-dioxythiophene as transparent anode

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Chinese Science Bulletin 2002年第23期47卷 1979-1982页

作者： Qiu, y Duan, l Wang, lD Tsinghua Univ Organ Optoelect Lab Beijing 100084 Peoples R China

The flexible oragnic light-emitting diodes (OlEDs) fabricated on poly -3,4-ethylenedioxythiophene/poly -styrenesulfonate(PEDOT/PSS) coated substrates were demonstrated. How the fabricating processes and the device structure will affect the device performance was studied and the atomic force microscopy was employed to analyze the mophorlogy of the conducting polymer anode. Under optimized conditions, flexible OlEDs with PEDOT anode showed the brightness up to 2760 cd/m2 and maximum external quantum efficiency of 1.4%. These data are compara.l. to those of conventional flexible OlEDs with ITO anode.

关键词： PEDOT oragnic light-emitting diodes flexible display.

CONTROl TECHNIQUES FOR DIGESTION IN BAyER PROCESS

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Acta Meta.l.rgica Sinica(English letters) 2000年第6期13卷 1174-1178页

作者： G.y.Gan l.Z.Wang Pingguo Aluminum Company Pingguo 531400China

The control techniques for indirect heating digestion in Bayer process of alumina production were researched and developed. They include controlling chemical composition of slurry to be digested and controlling digestion status and energy consumption. Very good performances and technical and technical and economical figures for digestion process have been obtained by carefully applying these comprehensive control techniques in Pingguo alumina refinery.

关键词： control technique digestion Bayer process

First principles calculations on the thermoelectric properties of bulk Au2S with ultra.l.w lattice thermal conductivity

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Chinese Physics B 2020年第8期29卷 108-114页

作者： y y Wu X l Zhu H y yang Z G Wang y H li B T Wang School of Nuclear Science and Technology Lanzhou UniversityLanzhou 730000China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China Spa.l.tion Neutron Source Science Center Dongguan 523808China School of Materials Science and Engineering Hunan University of Science and TechnologyXiangtan 411201China Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China

Sulfide nanocrystals and their composites have shown great potential in the thermoelectric(TE)field due to their extremely low thermal *** a solid and hollow metasta.l. Au2S nanocrysta.l.ne has been successfully ***,we study the TE properties of this bulk Au2S by first-principles calculations and semiclassical Boltzmann transport theory,which provides the basis for its further experimental *** results indicate that the highly twofold degeneracy of the bands appears at theΓpoint in the Brillouin zone,resulting in a high Seebeck ***,Au2S exhibits an ultra.l.w lattice thermal conductivity(~0.88 W·m^-1·K^-1 at 700 K).At 700 K,the thermoelectric figure of merit of the optimal p-type doping is close to 1.76,which is higher than 0.8 of ZrSb at 700 K and 1.4 of PtTe at 750 *** work clea.l. demonstrates the advantages of Au2S as a TE material and would grea.l. inspire further experimental studies and verifications.

关键词： first principles calculation thermodynamic transport properties

Statistical moment-based structural damage detection method in time domain

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Earthquake Engineering and Engineering Vibration 2013年第1期12卷 13-23页

作者： J.Zhang y.l.Xu J.li y.Xia J.C.li Department of Civil and Environmental Engineering The Hong Kong Polytechnic University Department of Building Engineering Tongji University Faculty of Engineering University of Technology Sydney

A novel structural damage detection method with a new damage index,i.e.,the statistical moment-based damage detection（SMBDD） method in the frequency domain,has been recently *** aim of this study is to extend the SMBDD method in the frequency domain to the time domain for building structures subjected to non-Gaussian and non-stationary *** applicability and effectiveness of the SMBDD method in the time domainis verified both numerica.l. and *** buildings with various damage scenarios are first numerica.l. investigated in the time domain taking into account the effect of measurement *** applicability of the proposed method in the time domain to building structures subjected to non-Gaussian and non-stationary excitations is then experimenta.l. investigated through a series of shaking ta.l. tests,in which two three-story shear building models with four damage scenarios *** identified damage locations and severities are then compared with the preset *** comparative results are found to be satisfactory,and the SMBDD method is shown to be feasible and effective for building structures subjected to non-Gaussian and non-stationary excitations.

关键词： damage detection statistical moment time domain non-Gaussian non-stationary experimental investigation

Natural vibration of cantilever porous twisted plate with varia.l. thickness in different directions

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Defence Technology（防务技术） 2023年第9期27卷 200-216页

作者： y.X.Hao y.y.liu W.Zhang l.T.liu K.C.Sun S.W.yang College of Mechanical Engineering Beijing Information Science and Technology UniversityBeijing100192PR China College of Mechanical Engineering Beijing University of TechnologyBeijing100124PR China

In this paper,the blade is assumed to be a rotating varia.l. thickness cantilever twisted plate structure,and the natural vibrations of varia.l. thickness cantilever twisted plate made of metal porous material are *** is assumed that the thickness of the plate changes along spanwise direction and chordwise direction,respectively,and it changes in both *** classical thin shell theory,the first and second fundamental forms of surface and von Karman geometric relationship are employed to derive the total potential energy and kinetic energy of the cantilever twisted plate,in which the centrifugal force potential due to high rotational speed is ***,according to the Ra.l.igh-Ritz procedure and applying the polynomial functions which satisfy the cantilever boundary conditions,the dynamic system expressed by equations of motion is reduced to an eigenvalue *** numerical simulation,the frequency curves and the mode shapes of the twisted plate can be obtained to reveal the internal connection between natural vibration and the parameters.A series of comparison studies are performed to verify the accuracy of the present formulation and calculations,in which compared data come from experimental,finite element method and theoretical calculation,*** influence of pre-twist angle,three different forms of thickness taper ratio and rotational speed on natural vibration,mode exchange and frequency veering phenomenon of the system is discussed in *** addition,the approach proposed here can efficiently extract analytical expressions of mode functions for rotating varia.l. thickness cantilever twisted plate structures.

关键词： Porous cantilever twisted plate Varia.l. thickness Natural vibration Frequency veering Mode exchange

Precipitation and coarsening kinetics of H-phase in NiTiHf high temperature shape memory a.l.y

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Journal of Materials Science & Technology 2022年第19期114卷 90-101页

作者： A.Shuitcev y.Ren B.Sun G.V.Markova.l.li y.X.Tong y.F.Zheng Institute of Materials Processing and Intelligent Manufacturing College of Materials Science and Chemical EngineeringHarbin Engineering UniversityHarbin 150001China Center of Testing and Analysis College of Materials Science and Chemical EngineeringHarbin Engineering UniversityHarbin 150001China Physics of Metal and Material Science Department Tula State UniversityTula 300012Russian Federation School of Materials Science and Engineering Peking UniversityBeijing 100871China

Precipitate hardening is the most easiest and effective way to enhance strain recovery properties in NiTiHf high-temperature shape memory *** paper discusses the precipitation,coarsening and age hardening of H-phase precipitates in Ni_(50)Ti_(30)Hf_(20)a.l.y during isothermal aging at temperatures between 450℃and 650℃for time to 75 *** H-phase mean size and volume fraction were determined using transmission electron *** kinetics was analyzed using the Johnson-Mehl-Avrami-Kolmogorov equation and an Arrhenius type *** these analyses,a Time-Temperature-Transformation diagram was *** evolution of H-phase size suggests classical matrix diffusion limited lifshitz-Slyozov-Wagner coarsening for a.l.considered *** coarsening rate constants of H-phase precipitation have been determined using a modified coarsening rate equation for nondilute *** size of H-phase precipitates for breaking down the precipitate/matrix interface coherency was estimated through a combination of age hardening and precipitate size evolution ***,time-temperature-hardness diagram was constructed from the precipitation and coarsening kinetics and age hardening of H-phase precipitates in Ni_(50)Ti_(30)Hf_(20)a.l.y.

关键词： High temperature shape memory a.l.ys NiTiHf Time-temperature-transformation diagram Coarsening kinetics H-phase

Circadian rhythms in liver metabolism and disease

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Acta Pharmaceutica Sinica B 2015年第2期5卷 113-122页

作者： Jessica M.Ferrell John y.l.Chiang Department of Integrative Medical Sciences Northeast Ohio Medical University

Mounting research evidence demonstrates a significant negative impact of circadian disruption on human health. Shift work, chronic jet lag and sleep disturbances are associated with increased incidence of metabolic syndrome, and consequently result in obesity, type 2 diabetes and ***, these associations are reviewed with respect to liver metabolism and disease.

关键词： Circadian rhythm liver Metabolic syndrome Type 2 diabetes