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Development of an aero-thermal coupled through-flow method for cooled turbines

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Science China(Technological Sciences) 2015年第12期58卷 2060-2071页

作者： GU ChunWei LI HaiBo song yin Key Laboratory for Thermal Science and Power Engineering of Ministry of Education Department of Thermal EngineeringTsinghua University

The influence of complicated interaction between the flow field and heat transfer in cooled turbines becomes more and more significant with the increasing turbine inlet temperature. However, classical through-flow methods did not take into account the influence of the interaction caused by air cooling. The aerodynamic design and cooling design of cooled turbines were carried out separately, and the iterations between the aerodynamic design and cooling design led to a long design period and raised the design cost. To shorten the design period and decrease the design cost, this paper proposes a concise aero-thermal coupled through-flow method for the design of cooled turbines, taking into account the influence of the complicated interaction between the flow field and heat transfer in cooled turbines. The governing equations, such as energy equation and continuity equation in classical through-flow method are re-derived theoretically by considering the historical influence of cooling with the same method that deals with viscous losses in this paper. A cooling model is developed in this method. The cooled blade is split into a number of heat transfer elements, and the heat transfer is studied element by element along both the span and the chord in detail. This paper applies the method in the design of a two-stage axial turbine, of which the first stator is cooled with convective cooling. With the prescribed blade temperature limitation and the knowledge of the flow variables of the mainstream at the turbine inlet, such as the total pressure, total temperature and mass flow rate, the convergence of the calculation is then obtained and the properties of the flow field, velocity triangles and coolant requirement are well predicted. The calculated results prove that the aero-thermal coupled through-flow method is a reliable tool for flow analysis and coolant requirement prediction in the design of cooled turbines.

关键词： aero-thermal coupled through-flow method cooling model cooled turbines

Stable Propagating Waves and Wake Fields in Relativistic Electromagnetic Plasma

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Communications in Theoretical Physics 2008年第3期49卷 753-758页

作者： XIE Bai-song yin Xin-Tao The Key Laboratory of Beam Technology and Materials Modification of Ministry of Education Beijing Normal University Beijing 100875 China

Stable propagating waves and wake fields in relativistic electromagnetic plasma are investigated. The incident electromagnetic field has a finite initial constant amplitude meanwhile the longitudinal momentum of electrons is taken into account in the problem. It is found that in the moving frame with transverse wave group velocity the stable propagating transverse electromagnetic waves and longitudinal plasma wake fields can exist in the appropriate regime of plasma.

关键词： nonlinear wave propagation laser-plasma interactions

On Two-stage Estimate Based on Independent Estimate of Covariance Matrix

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Acta Mathematica Sinica,English Series 2006年第1期22卷 283-288页

作者： Su Ju yin song Gui WANG College of Applied Sciences Beijing University of Technology Beijing 100022 P. R. China

When an independent estimate of covariance matrix is available, we often prefer two-stage estimate （TSE）. Expressions of exact covarianee matrix of the TSE obtained by using all and some covariables in eovariance adjustment approach are given, and a necessary and sufficient condition for the TSE to be superior to the least square estimate and related large sample test is also established. Furthermore the TSE, by using some covariables, is expressed as weighted least square estimate. Basing on this fact, a necessary and sufficient condition for the TSE by using some covariables to be superior to the TSE by using all eovariables is obtained. These results give us some insight into the selection of covariables in the TSE and its application.

关键词： two-stage estimate covariance adjusted estimate canonical correlation coefficients

Characterization of 4-Aryl-5-ethoxycarbonyl-6-methyl-3,4-dihydro-pyrimidin-2(1H)-thiones by EI-TOF Mass Spectrometry

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Chemical Research in Chinese Universities 2006年第1期22卷 40-44页

作者： LI Qian-rong XUE song yin Hao Hefei National Laboratory for Physical Sciences at Microscale and Department of Chemistry University of Science and Technology of China Hefei 230026 P. R. China

The electron impact （EI） time-of-flight mass spectra （TOFMS） of the title compounds （ thioxo-Biginelli compounds） were studied to establish their fragmentation pathways. With a TOF instrument of high resolution, the exact mass for each fragment was determined. These data were used to infer the molecular formulas and the ionic elemental compositions for all the compounds through interpretation by software. By further applying chemical intuition, majority of the fragmentation ions were fully assigned. All the compounds give strong signals（ average 76% ） for their molecular ions in the El spectra. Two kinds of characteristic fragmentation pathways from the molecular ion were observed. One is related to the loss of the ester group, forming a resonance stabilized ion with a moderate abundance（ average 40% ）. The other concerns the loss of the aromatic-ring radical, forming another resonance stabilized ion at m/z 199 with a high abundance（ average 79% ）, from which further important fragmentations including the formation of an ion at m/z 171 （average 24% ） by the loss of C2H2 （via the McLafferty rearrangement）, and an ion at m/z 153（ average 10% ） by the elimination of a water molecule preceed. In addition, ion [ M - Et ]^＋ with a high abundance（average 62% ） is a characteristic for the Biginelli compounds with an ethoxycarbonyl group. Differences and similarities among the fragmentations observed from the EI-TOFMS of oxo-Biginelli compounds are discussed.

关键词： Beginelli compound 3,4-Dihydropyrimidinthione Time-of-flight mass spectrometry Electron impact

Classifications of Isoparametric Hypersurfaces in Randers Space Forms

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Acta Mathematica Sinica,English Series 2020年第9期36卷 1049-1060页

作者： Qun HE Pei Long DONG song Ting yin School of Mathematical Sciences Tongji UniversityShanghai 200092P.R.China Department of Mathematics and Computer Science Tongling UniversityTongling 244000P.R.China Key Laboratory of Applied Mathematics(Putian University) Fujian Province University

In this paper,we give the complete classifications of isoparametric hypersurfaces in Randers space *** studying the principal curvatures of anisotropic submanifolds in a Randers space(N,F)with the navigation data(h,W),we find that a Randers space form(N,F,dμBH)and the corresponding Riemannian space(N,h)have the same isoparametric hypersurfaces,but in general,their isoparametric functions are *** give a necessary and sufficient condition for an isoparametric function of(N,h)to be isoparametric on(N,F,dμBH),from which we get some examples of isoparametric functions.

关键词： Isoparametric hypersurface Randers space form principal curvature anisotropic sub-manifold

Field testing of shear strength of granite residual soils

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第9期16卷 3718-3732页

作者： song yin Pengfei Liu Xianwei Zhang Wenyuan He Pan Yan Yuzhou Sun School of Civil Engineering and Architecture Zhongyuan University of TechnologyZhengzhou450007China State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430071China

The characteristics of residual soils are very different from those of sedimentary *** the strength characteristics of sedimentary soils have been studied extensively,the shear strength characteristics of granitic residual soils(GRS)subjected to the weathering of parent rocks have rarely been *** this study,the shear strength characteristics of GRS in the Taishan area of southeast China(TSGRS)were studied by field and laboratory *** field tests consisted of a cone penetration test(CPT),borehole shear test(BST),self-boring pressuremeter test(SBPT),and seismic dilatometer Marchetti test(SDMT).The shortcomings of laboratory testing are obvious,with potential disturbances arising through the sampling,transportation,and preparation of soil *** to the special structure of GRS samples and the ease of disturbance,the results obtained from laboratory tests were generally lower than those obtained from situ *** CPT and scanning electron microscopy(SEM)results indicated significant weathering and crustal hardening in the shallow *** resulted in significant differences in the strength and strength parameters of shallow soil obtained by the *** on the SDMT and SBPT results,a comprehensive evaluation method of shear strength for TSGRS was *** SBPT was suitable for evaluating the strength of shallow *** material index(ID)and horizontal stress index(KD)values obtained by the SDMT satisfied the empirical relationship proposed by Marchetti based on the ID index,and were therefore considered suitable for the evaluation of the shear strength of deep GRS.

关键词： Granite residual soils Shear strength Field tests Self-boring pressuremeter Seismic dilatometer Borehole shear test

One-pot synthesis of diarylimidazolium salts from 1H-imidazole

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Chinese Chemical Letters 2013年第9期24卷 773-776页

作者： Tai-Yong Lv Lei Yang yin-song Zhao Fei-Jie song Jing-Bo Lan Jing-song You Ge Gao Key Laboratory of Green Chemistry and Technology of Ministry of Education College of Chemistry

Diarylimidazolium salts （3） were directly synthesized starting from lH-imidazole （1） by a one-pot strategy using diaryliodonium salts as the arylating reagents, lH-Benzimidazole and 1H-1,2,4-triazole are suitable ... 详细信息

关键词： Diaryliodonium salt 1H-lmidazole Copper catalysis Diarylimidazolium saltNHC

Effect of Gd on microstructure and refinement performance of Al-5Ti-B alloy

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China Foundry 2021年第3期18卷 223-228页

作者： Dong-song yin Ning Zhang Ke-ju Chen Yun-long Zhang School of Materials Science and Engineering Heilongjiang University of Science and TechnologyHaerbin 150022China School of Materials Science and Engineering Jiamusi UniversityJiamusi 154007China

Al-5Ti-B and Al-5Ti-B-Gd master alloy refiners were fabricated by fluorine salt casting *** microstructure and phase constitution of the master alloys were investigated by scanning electron microscopy (SEM),transmission electron microscopy (TEM) and X-ray diffraction (XRD).The results show that Al-Ti-B alloy refiner consists of Al_(3)Ti phase and TiB2 *** Gd is introduced into the intermediate alloy,Ti_(2)Al_(20)Gd phase appears in the alloy,the size of Al_(3)Ti is significantly reduced,and Ti-Al-Gd phase is found in the edge of Al_(3)Ti *** the same time,some independent Ti-Al-Gd phases appear in local areas,which are Ti_(2)Al_(20)Gd phase determined by micro-area electron diffraction *** and calculation results of the high-resolution images of the Ti_(2)Al_(20)Gd/Al structure show that there is no other compound at the junction between the Ti_(2)Al_(20)Gd phase and Al,and Ti_(2)Al_(20)Gd phase has a great difference in atomic space with the α-Al,which cannot be directly used as heterogeneous ***,after being decomposed in the aluminum melt,the Ti_(2)Al_(20)Gd phase can promote the refinement effect of the *** the Al-Ti-B-Gd master alloy,there are many dispersed Al_(3)Ti particles with a size of less than 1 μm,which can promote the Al-5Ti-B refining effect.

关键词： Al-5Ti-B alloy refiner Al_(3)Ti rare earth Gd Ti_(2)Al_(20)Gd

Structural and photoluminescent properties of ZnO films deposited by radio frequency reactive sputtering

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Science China(Physics,Mechanics & Astronomy) 2007年第3期50卷 281-286页

作者： PENG XingPing WANG ZhiGuang song yin JI Tao ZANG Hang YANG yingHu JIN YunFan Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China School of Physics Science and Technology Lanzhou UniversityLanzhou 730000China

Zinc oxide films with c-axis preferred orientation were deposited on silicon (100) substrates by radio frequency (RF) reactive sputtering. The properties of the samples were characterized by X-ray diffractometer, X-ray photoelectron spectroscopy and fluorescent-spectrophotometer. The effect of sputtering power and substrate temperature on the structural and photoluminescent (PL) properties of the ZnO films was investigated. The results indicated that when the sputtering power is 100 W and the substrate temperature is 300–400°C, it is suitable for the growth of high c-axis orientation and small strain ZnO films. A violet peak at about 380 nm and a blue band at about 430 nm were observed in the room temperature photoluminescence spectra, and the origin of blue emission was investigated.

关键词： ZnO films XRD spectra PL spectra substrate temperature RF reactive sputtering