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Effect of Guide Va.e on Pressure Loss a.d Hea. Tra.sfer cha.a.teristics of Supercritica. cO_(2)in u-Sha.ed cha.nel

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Journa. of Therma. Science 2022年第3期31卷 701-711页

作者： LuO Xia.bo Ya.G ze-Na. ZHa.G Jia.wu cHEN Wei cHYu Minking School of a.rona.tics a.d a.trona.tics Sichuan UniversityChengdu610065China Sichua. Ga. Turbine Esta.lishment Aero Engine Corporation of ChinaMianyang621703China

u-sha.ed cha.nel is a.common unit structure in hea. *** pressure loss a.d hea. tra.sfer cha.a.teristics of u-sha.ed cha.nel ha.e importa.t influence on the comprehensive performa.ce of hea. *** this pa.er,combined with the thermo-physica. property of supercritica. cO_(2)(ScO_(2)),the influence of the guide va.es on the pressure loss a.d hea. tra.sfer cha.a.teristics of ScO_(2)in u-sha.ed cha.nel wa. studied *** four different guide va.es included integra. guide va.e,two-sta.e symmetric guide va.e,two-sta.e a.ymmetric guide va.e a.d discrete guide ***_(2)Rea. Ga. Property file(RGP)wa. imported into a.SYS cFX commercia. softwa.e for ca.cula.ion,a.d the turbulence model wa. SST k-ω.a. the sa.e time,the influence of different inlet Reynolds numbers a.d hea.ing conditions of cha.nel wa.l were a.so studied.

关键词： supercritica. cO_(2) horizonta. u-sha.ed cha.nel guide va.e pressure loss hea. tra.sfer

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微型无人机视觉定位与环境建模研究

电子科技大学学报 2017年第3期46卷 543-548页

作者：吕科施泽南李一鹏中国科学院大学工程科学学院清华大学信息科学技术学院

同步定位与环境建模(SLa.)是实现无人机自主飞行和智能导航的关键技术。该文提出了适用于微型无人机的视觉定位与环境建模方法,针对RGB-D传感器使用point-pla.e IcP点云匹配算法实现视觉自主定位,利用并行计算加速以满足无人机控制的实... 详细信息

同步定位与环境建模(SLa.)是实现无人机自主飞行和智能导航的关键技术。该文提出了适用于微型无人机的视觉定位与环境建模方法,针对RGB-D传感器使用point-pla.e IcP点云匹配算法实现视觉自主定位,利用并行计算加速以满足无人机控制的实时性要求;采用TSDF算法融合多帧观测的点云数据,实现了无人机对未知目标环境区域的模型重建;将视觉SLa.系统与无人机载IMu传感器融合,进一步提升了自主定位和建模精度。实际搭建了微型无人机视觉与环境建模验证系统,室内环境下可以达到0.092 m的定位偏差和60 Hz的更新速率,满足了无人机控制的精度和实时性要求,验证了该方法的有效性。

关键词：环境建模微型无人机多传感器同步定位与环境建模视觉定位

Stress, Roughness a.d Reflectivity Properties of Sputter-Deposited B4c coa.ings for X-Ra. Mirrors

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chinese Physics Letters 2019年第12期36卷 17-21页

作者： Jia.Li wu Run-ze Qi Qiu-Shi Hua.g Yu-Fei Feng Zha.-Sha. Wa.g Zi-Hua.Xin Depa.tment of Physics Shanghai UniversityShanghai 200444 MOE Key La.ora.ory of a.va.ced Micro-Structured Ma.eria.s Shanghai 200092 Institute of Precision Optica. Engineering School of Physics Science and EngineeringTongji UniversityShanghai 200092

Boron ca.bide(B4c)coa.ings ha.e high reflectivity a.d a.e widely used a. mirrors for free-electron la.ers in the x-ra. ***,B4c coa.ings fa.rica.ed by direct-current ma.netron sputtering show a.strong compressive stress of a.out-3 *** cha.ging the a.gon ga. pressure a.d nitrogen-a.gon ga. mixing ra.io,we a.e a.le to reduce the intrinsic stress to less tha.-1 GPa.for a.50-nm-thick B4c *** is found tha. the stress in a.coa.ing deposited a. 10 m Torr is-0.69 GPa.the rms roughness of the coa.ing surfa.e is 0.53 nm,a.d the coa.ing reflectivity is 88%,which is lower tha. those of coa.ings produced a. lower working *** the working ga. conta.ns 8%nitrogen a.d 92%a.gon,the B4 c coa.ing shows not only-1.19 GPa.stress but a.so a.low rms roughness of 0.16 nm,a.d the mea.ured reflectivity is 93%a. the wa.elength of 0.154 nm.

关键词： coa.ing stress ca.bide

a.revised jump-diffusion a.d rota.ion-diffusion model

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chinese Physics B 2019年第5期28卷 216-221页

作者： Hua.Li Yu-Ha.g chen Bin-ze Ta.g Depa.tment of Physics Jinan University

Qua.i-ela.tic neutron sca.tering(QENS) ha. ma.y a.plica.ions tha. a.e directly rela.ed to the development of highperforma.ce functiona. ma.eria.s a.d biologica. ma.romolecules, especia.ly those conta.ning some wa.er. The a.a.ysis method of QENS spectra.da.a.is importa.t to obta.n pa.a.eters tha. ca. expla.n the structure of ma.eria.s a.d the dyna.ics of wa.er. In this pa.er, we present a.revised jump-diffusion a.d rota.ion-diffusion model(rJRM) used for QENS spectra.da.a.a.a.ysis. By the rJRM, the QENS spectra.from a.pure ma.nesium-silica.e-hydra.e(MSH) sa.ple a.e fitted well for the Q ra.ge from 0.3 ^(-1) to 1.9 ^(-1) a.d tempera.ures from 210 K up to 280 K. The fitted pa.a.eters ca. be divided into two kinds. The first kind describes the structure of the MSH sa.ple, including the ra.io of immobile wa.er(or bound wa.er) c a.d the confining ra.ius of mobile wa.er a.0. The second kind describes the dyna.ics of confined wa.er in pores conta.ned in the MSH sa.ple, including the tra.sla.iona. diffusion coefficient Dt, the a.era.e tra.sla.iona. residence timeτ0, the rota.iona. diffusion coefficient D_r, a.d the mea. squa.ed displa.ement(MSD) u^2. The r JRM is a.new pra.tica. method suita.le to fit QENS spectra.from porous ma.eria.s, where hydrogen a.oms a.pea. in both solid a.d liquid pha.es.

关键词： revised jump-diffusion a.d rota.ion-diffusion model (rJRM) da.a a.a.ysis of qua.i-ela.tic neutron sca.tering (QENS) spectra dyna.ics of wa.er ma.nesium-silica.e-hydra.e (MSH) sa.ples

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cS6a.60型压电陀螺动态校零研究

压电与声光 2000年第5期22卷 302-305页

作者：刘勇李泽莉吕志清四川压电与声光技术研究所重庆400060

阐述了针对 cS6a. 60型压电陀螺开发的动态校零技术 ,分析了校零原理及误差主要来源 ,并论述了采用单片机实现动态校零和误差补偿的技术方案和试验结果。该校零技术有效地提高了 cS6a. 60型压电陀螺的零位重复性和稳定性 ,不影响陀螺的... 详细信息

阐述了针对 cS6a. 60型压电陀螺开发的动态校零技术 ,分析了校零原理及误差主要来源 ,并论述了采用单片机实现动态校零和误差补偿的技术方案和试验结果。该校零技术有效地提高了 cS6a. 60型压电陀螺的零位重复性和稳定性 ,不影响陀螺的其他特性。成功地应用在机载雷达控制系统中。

关键词：动态校零压电陀螺单片机误差补偿

Experimenta. a.a.ysis of the mecha.ism of high-order polygona. wea. of wheels of a.high-speed tra.n

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Journa. of Zhejia.g university-Science a.a.plied Physics & Engineering) 2017年第8期18卷 579-592页

作者： Yue wu Xing Du He-ji ZHa.G ze-feng WEN Xue-song JIN Sta.e Key La.ora.ory of Tra.tion Power Southwest Jiaotong University Chengdu 610031 China

This pa.er presents a.deta.led investiga.ion, via.field experiment, into the mecha.ism of high-order polygona. wea. of wheels of a.new type of high-speed tra.n. The investiga.ion wa. ca.ried out during the performa.ce a.cepta.ce test of the tra.n a.d its initia. commercia. opera.ion. The investiga.ion covered the performa.ce a.cepta.ce test of 150 000 km a.d the commercia. opera.ion of a.out 150 000 km. In the performa.ce a.cepta.ce test of the first sta.e of a.out 70 000 km, a. 200-250 km/h with full loa.ing a.d sometimes overloa.ing by 30%, the serious polygona. wea. of 23-order took pla.e on a.l the wheels of the tra.n, a.d wa. mea.ured a.d a.a.yzed in deta.l. a.l the potygonized wheels were re-profiled beca.se the polygona. wea. ha. ca.sed strong vibra.ion a.d da.a.e to the tra.n pa.ts. a.ter re-profiling, the vibra.ion of the tra.n a.d tra.k a.d the wea. sta.us of the wheels were mea.ured a.d a.a.yzed a. different test milea.es a.cording to the polygona. wea. situa.ion of the wheels. The mea.ured vibra.ion of the tra.n includes the a.celera.ions a. different positions of a.motor ca. a.d a.tra.l ca.. The vibra.ion modes of the key pa.ts of the bogies of the two ca.s were ca.cula.ed. Mea.while, the tra.k resona.t frequencies were investiga.ed a. the site. The purpose of the a.ove tests a.d a.a.ysis is try to find the frequency of work mode ma.ching the pa.sing frequency of the high-order wheel polygon. The present investiga.ion shows tha. one of the working models ca.ses the forma.ion a.d development of the high-order wheel polygona. wea.. The growth of this wea. wa. effectively reduced through the frequent cha.ging of the running speed of the tra.n opera.ing on the wa. ba.k a.d forth every da..

关键词： High-speed tra.n Wheel High-order polygona. wea. Field test Model a.a.ysis System resona.ce frequency

铜催化的2,x-二溴吡啶与硫酚的高度区域选择性偶联反应

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浙江大学学报（理学版） 2013年第5期40卷 548-552,569页

作者：吕泽光周其忠台州学院化学系浙江台州318000 中国科学院上海有机化学研究所有机氟化学重点实验室上海200032

以cuI为催化剂,L-脯氨酸为配体,cs2cO3为碱,DMF为溶剂,在30℃下,用2,x-二溴吡啶和硫酚或硫醇反应,高产率和高区域选择性地得到2位烃硫基取代的吡啶.该反应可应用于药物的合成.

关键词： cuI L-脯氨酸硫酚催化区域选择性

Influence of Residua. Stress on Sha.e of Hea.y-ga.ge,High-strength Steel ca.sed by cooling Process a.ter Hot Rolling

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Journa. of Iron a.d Steel Resea.ch Interna.iona. 2016年第6期23卷 547-552页

作者： Shui-ze Wa.G Yong-lin Ka.G Guo-ming ZHu Wen LIa.G School of Ma.eria.s Science a.d Engineering University of Science and Technology Beijing Resea.ch a.d Development center Wuhan Iron & Steel(Group)Co.Ltd.

The cooling process following hot rolling ha. a.significa.t effect on the sha.e qua.ity of a.hot-rolled *** tempera.ure a.d stress fields in the cooling process for a.14 mm thick strip with yield strength of 500 MPa.gra.e were a.a.yzed by the finite element method a.d a.tua. test da.a.a.d the rela.ionship between residua. stress a.d sha.e defects wa. ***,the sma.l-crown rolling process a.d the coil slow cooling process were *** results indica.e tha. these processes improved the sha.e qua.ity of the fina. product significa.tly.

关键词： rolling strip fla.ness ga.ge rolled crown thick tensile buckling defects

La.e Mesozoic Tectono-Therma. History in the South Ma.gin of Grea. Xing’a. Ra.ge,NE china.Insights from Zircon a.d a.a.ite(u-Th)/He a.es

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Journa. of Ea.th Science 2022年第1期33卷 36-44页

作者： Wen Zha.g Shua.gfeng Zha. Jingbo Sun ze Shen Wen chen La.ora.ory of Isotope Thermochronology Key Laboratory of Deep-Earth Dynamics of Ministry of Natural ResourcesInstitute of GeologyChinese Academy of Geological SciencesBeijing 100037China

The La.e Mesozoic tectono-therma. evolution a.d geodyna.ic setting of the Grea. Xing’a. Ra.ge(GXR),pa.ticula.ly in the south ma.gin,a.e still *** this study,we present origina. low-tempera.ure thermochronologica. da.a.of six gra.itoid sa.ples collected from Ma.nzi pluton in the south ma.gin of the *** a.a.ite a.d zircon(u-Th)/He a.es va.y of 70.8 ± 4.3-119.0 ±7.0 Ma.a.d 120.0 ± 7.1-146.7 ± 8.7 Ma.*** numerica. inverse modeling results revea. tha. the gra.itoid plutons experienced a.ra.id cooling a.d exhuma.ion sta.e during Ea.ly creta.eous with a.ra.e of ~5.0-6.0 ℃/Ma.a.d ~0.14-0.17 mm/yr,respectively,including the western minor pluton empla.ed during Ea.ly Permia. a.d the ma.or pluton crysta.lized in la.est Jura.sic,corresponding to the extensiona. tectonics in NE *** ra.id exhuma.ion processes in the south ma.gin of the GXR during the Ea.ly creta.eous could be rela.ed to both the rollba.k of Pa.eo-Pa.ific ocea.ic pla.e a.d the colla.se of thickened crust in the Mongol-Okhotsk Orogen.

关键词： Grea. Xing’a. Ra.ge tectono-therma. history (u-Th)/He da.ing extensiona. tectonics Mongol-Okhotsk colla.se Pa.eo-Pa.ific subduction geochemistry