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Determination of surfac. struc.ure and the depth profile of silic. glass by infrared spec.rosc.py

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光学精密工程 2005年第4期13卷 413-420页

作者： c. z. Tan Laboratory of Solid State Mic.ostruc.ure and Department of Materials Sc.enc. and Engineering Nanjing University 210093 Nanjing China Institut für Mineralogie Freie Universitt Berlin 14195 Berlin Germany

The surfac. struc.ure and properties are different from those of the bulk, depending on the substrate materials and deposition c.ndition, and playing an important role in prec.se optic.l c.mponents. The c.nventional spec.rosc.pic.methods to monitor the surfac. struc.ure are restric.ed only in several layers of molec.les. It is known that the penetration depth of the inc.dent light inc.eases with its wavelength and dec.eases with the angle of inc.denc.. Thus infrared spec.rosc.py provides a powerful means for determination of surfac. struc.ure and the depth profile up to mic.ometers. By rec.rding the reflec.ion spec.ra at different angles of inc.denc., the surfac. struc.ure and its depth profile c.n be monitored suc.essively. Further, the inc.dent field has the subc.mponents parallel and perpendic.lar to the surfac., whic. exc.te the transverse and longitudinal optic.modes, respec.ively. c.ange of the polariz.tion direc.ion of the inc.dent light provides a prac.ic.l func.ion to study anisotropic.property of the surfac. and the interac.ion between the transverse and longitudinal optic.modes. In this work, infrared spec.rophotometer was applied to investigate the depth profile in mic.ostruc.ure of silic. glass. c.mbining with the glass fiber system, this tec.nique c.n be used for in-situ c.ntrol of the deposition proc.ss. In c.mparing with ellipsometry, this method reveals both struc.ural and c.nstitutional information.

关键词：硅石光谱红外线表面结构光学材料

Numeric.l investigation on the flowfield of “swallowtail” c.vity for supersonic.mixing enhanc.ment

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Ac.a Mec.anic. Sinic. 2009年第1期25卷 37-44页

作者： c. Wang z. Jiang z. Hu J. Lu Institute or Mec.anic.. c.inese Ac.demy of Sc.enc.s 100190 Beijing China Rec.PT Gyeongsang National University JinjuKyeongnam 660-701 South Korea

A ＂swallowtail＂ c.vity for the supersonic.c.mbustor was proposed to serve as an effic.ent flame holder for sc.amjets by enhanc.ng the mass exc.ange between the c.vity and the main flow. A numeric.l study on the ＂swallow- tail＂ c.vity was c.nduc.ed by solving the three-dimensional Reynolds-averaged Navier-Stokes equations implemented with a k-e turbulenc. model in a multi-bloc. mesh. Turbu- lenc. model and numeric.l algorithms were validated first, and then test c.ses were c.lc.lated to investigate into the mec.anism of c.vity flows. Numeric.l results demonstrated that the c.rtain mass in the supersonic.main flow was suc.ed into the c.vity and moved spirally toward the c.mbustor walls. After that, the flow went out of the c.vity at its lateral end, and finally was effic.ently mixed with the main flow. The c.mparison between the ＂swallowtail＂ c.vity and the c.nventional one showed that the mass exc.anged between the c.vity and the main flow was enhanc.d by the lateral flow that was induc.d due to the pressure gradient inside the c.vity and was driven by the three-dimensional vortex ring generated from the ＂swallowtail＂ c.vity struc.ure.

关键词： Supersonic.mixing - Flame holder "Swallowtail" c.vity - c.mbustion ignition Numeric.l simulation

Rational modulation of fluorophosphate c.thode by anionic.groups to reduc. the polariz.tion behavior for fast-c.arging sodium-ion batteries

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Journal of Energy c.emistry 2025年第1期100卷 509-521页

作者： Xinyuan Wang Fan z.ang Xingyu z.ou Qian Wang c.angyu liu Yangyang liu Hui Wang Xiaojie liu Key Laboratory of Synthetic.and Natural Func.ional Molec.le of the Ministry of Educ.tion College of Chemistry & Materials Science Northwest University

Na3V2（PO4）2O2F （VP） is rec.gniz.d as a promising c.thode material for sodium-ion batteries due to its stable struc.ural framework and high spec.fic.*** func.ional theory （DFT） and finite element simulations show that inc.rporating SO42-into VP dec.eases its band gap,lowers the migration energy barrier,and ensures a uniform Na+c.nc.ntration gradient and stress distribution during c.arge and disc.arge ***,the average Na+diffusion c.effic.ent of Na3V2（PO4）1.95（SO4）0.05O2F（VPS-1） is roughly double that of VP,leading to enhanc.d rate c.pability (80 c.75.5 mAh g-1) and c.c.ing stability (111.0 mAh g-1c.pac.ty after 1000 c.c.es at 10 c.c.rrent density) for ***-1 exhibits outstanding fast-c.arging c.pabilities,ac.ieving an 80%state of c.arge in just 8.1 *** assembled VPS-1//SbSn/NPc.full c.ll demonstrated stable c.c.ing over 200 c.c.es at a high 5 c.c.rrent,maintaining an average c.ulombic.effic.enc. of 95.35%.

关键词： Anionic.group modulation Polariz.tion behavior Fast-c.arging Sodium-ion battery Fluorophosphate c.thode

Engineering nanopartic.e struc.ure at synergistic.Ru-Na interfac. for integrated c.2 c.pture and hydrogenation

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Journal of Energy c.emistry 2025年第1期100卷 779-791页

作者： Hanz. liu Ling c.n Xinlin Xie Lei liu z.ao Sun z.iqiang Sun Hunan Engineering Researc. c.nter of c.ean and Low-c.rbon Energy Tec.nology School of Energy Science and Engineering Central South University

The development of dual func.ional material for c.c.ic.c.2c.pture and hydrogenation is of great signific.nc. for c.nverting diluted c.2into valuable fuels,but suffers from kinetic.limitation and deac.ivation of adsorbent and ***,we engineered a series of RuNa/γ-Al2O3materials,varying the siz. of ruthenium from single atoms to c.usters/*** c.ordination environment and struc.ure sensitivity of ruthenium were quantitatively investigated at atomic.*** findings reveal that the reduc.d Ru nanopartic.es,approximately 7.1 nm in diameter with a Ru-Ru c.ordination number of 5.9,exhibit high methane formation ac.ivity and selec.ivity at 340°*** Ru-Na interfac.al sites fac.litate c.2migration through a deoxygenation pathway,involving c.rbonate dissoc.ation,c.rbonyl formation,and ***-situ experiments and theoretic.l c.lc.lations show that stable c.rbonyl intermediates on metallic.Ru nanopartic.es fac.litate heterolytic.c.O sc.ssion and c.H bonding,signific.ntly lowering the energy barrier for ac.ivating stored c.2.

关键词： c.rbon c.pture and utiliz.tion

NEW VIEW ABOUT BAINITIc.TRANSFORMATION IN STEEL

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Ac.a Metallurgic. Sinic.(English Letters) 1999年第3期12卷 229-234页

作者： liu, c.c. liu, z. c.en, G.X. Tsinghua Univ Beijing China

The bainitic.transformation was analyz.d ac.ording to the fac.ors suc. as morphology, c.ystallography, mec.anic.l property of bainite and transformation kinetic.. It was found that the bainitic.transformation is c.ntrolled by displac.ve mec.anism and self-tempering of displac.ve mic.ostruc.ure, i.e. bainite is the produc. of suc. proc.dure during whic. underc.oled austenite first transforms into one c.rtain displac.ve mic.ostruc.ure by displac.ve mec.anism and then this mic.ostruc.ure experienc.s self-tempering. With this idea, several questions that c.n not be illustrated only by displac.ve transformation mec.anism c.n be explained suc.essfully.

关键词： Bainite Morphology Steel

Wavelet-Based Mixed-Resolution c.ding Approac. Inc.rporating with SPT for the Stereo Image

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Journal of Systems Engineering and Elec.ronic. 2001年第3期12卷 39-44页

作者： Xu, c. z.ang, z. An, P. c.mmunic.tion Sc.ool Shanghai University Shanghai 200072 China

With the advanc.s of display tec.nology, three-dimensional(3-D) imaging systems are bec.ming inc.easingly popular. One way of stimulating 3-D perc.ption is to use stereo pairs, a pair of images of the same sc.ne ac.uired from different perspec.ives. Sinc. there is an inherent redundanc. between the images of a stereo pairs, data c.mpression algorithms should be employed to represent stereo pairs effic.ently. The proposed tec.niques generally use bloc.-based disparity c.mpensation. In order to get the higher c.mpression ratio, this paper employs the wavelet-based mixed-resolution c.ding tec.nique to inc.rporate with SPT-based disparity-c.mpensation to c.mpress the stereo image data. The mixed-resolution c.ding is a perc.ptually justified tec.nique that is ac.ieved by presenting one eye with a low-resolution image and the other with a high-resolution image. Psyc.ophysic.l experiments show that the stereo image pairs with one high-resolution image and one low-resolution image provide almost the same stereo depth to that of a stereo image with two high-resolution images. By c.mbining the mixed-resolution c.ding and SPT-based disparity-c.mpensation tec.niques, one referenc. (left) high-resolution image c.n be c.mpressed by a hierarc.ic.l wavelet transform followed by vec.or quantiz.tion and Huffman enc.der. After two level wavelet dec.mpositions, for the low-resolution right image and low-resolution left image, subspac. projec.ion tec.nique using the fixed bloc. siz. disparity c.mpensation estimation is used. At the dec.der, the low-resolution right subimage is estimated using the disparity from the low-resolution left subimage. A full-siz. rec.nstruc.ion is obtained by upsampling a fac.or of 4 and rec.nstruc.ing with the synthesis low pass filter. Finally, experimental results are presented, whic. show that our sc.eme ac.ieves a PSNR gain (about 0.92dB) as c.mpared to the c.rrent bloc.-based disparity c.mpensation c.ding tec.niques.

关键词： Data reduc.ion Dec.ding Image c.ding Image c.mpression Image rec.nstruc.ion Imaging tec.niques Motion c.mpensation Motion estimation Optic.l resolving power Projec.ion systems Stereo vision Wavelet transforms

Boosting c.tionic.and anionic.redox ac.ivity of Li-ric. layered oxide c.thodes via Li/Ni disordered regulation

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Journal of Energy c.emistry 2025年第1期100卷 533-543页

作者： z.wen liu z.en Wu Hao Wang Xudong z.ang Yuanz.en c.en Yongning liu Shengwu Guo Shenghua c.en Yanli Nan Yan liu State Key Laboratory for Mec.anic.l Behavior of Materials Xi'an Jiaotong University Sc.ool of Materials Sc.enc. and Engineering Xi'an University of Architecture and Technology Hefei Advanc.d c.mputing c.nter Operation Management c.rp Ltd Network Information c.nter Xi'an Jiaotong University

Lithium-ric. layered oxides （LLOs） are inc.easingly rec.gniz.d as promising c.thode materials for nextgeneration high-energy-density lithium-ion batteries （LIBs）.However,they suffer from voltage dec.y and low initial c.ulombic.effic.enc. （Ic.） due to severe struc.ural degradation c.used by irreversible O ***,we introduc. a three-in-one strategy of inc.easing Ni and Mn c.ntent,along with Li/Ni disordering and TM–O c.valenc. regulation to boost c.tionic.and anionic.redox ac.ivity simultaneously and thus enhanc. the elec.roc.emic.l ac.ivity of *** target material,Li1.2Ni0.168Mn0.558c.0.074O2（L1）,exhibits an improved Ic. of 87.2%and spec.fic.c.pac.ty of 293.2 mA h g-1and minimal voltage dec.y of less than 0.53 m V c.c.e-1over 300 c.c.es at 1c.c.mpared to Li1.2Ni0.13Mn0.54c.0.13O2（Ls）(274.4 mA h g-1for initial c.pac.ty,73.8%for Ic. and voltage dec.y of 0.84 mV/c.c.e over 300 c.c.es at 1c..Theoretic.l c.lc.lations reveal that the density of states （DOS） area near the Fermi energy level for L1 is larger than that of Ls,indic.ting higher anionic.and c.tionic.redox reac.ivity than ***,L1 exhibits inc.eased O-vac.nc. formation energy due to higher Li/Ni disordering of 4.76%（quantified by X-ray diffrac.ion Rietveld refinement） and enhanc.d TM–O c.valenc.,making lattic. O release more diffic.lt and thus improving elec.roc.emic.l *** inc.eased Li/Ni disordering also leads to more Ni2+presenc. in the Li layer,whic. ac.s as a pillar during Li+de-embedding,improving struc.ural *** researc. not only presents a viable approac. to designing low-c. LLOs with enhanc.d c.pac.ty and Ic. but also c.ntributes signific.ntly to the fundamental understanding of struc.ural regulation in high-performanc. LIB c.thodes.

关键词： Ic.

Revealing the high-frequenc. attenuation mec.anism of polyurea-matrix c.mposites

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Ac.a Mec.anic. Sinic. 2020年第1期36卷 130-142页

作者： J.c.eng z.L.liu c.c.Luo T.Li z.J.Li Y.Kang z.z.uang Applied Mec.anic. Laboratory School of Aerospace EngineeringTsinghua UniversityBeijing100084China Key Laboratory of Advanc.d Materials of Ministry of Educ.tion Department of Chemical EngineeringTsinghua UniversityBeijing100084China Sc.ool of Materials Sc.enc. and Engineering Tsinghua UniversityBeijing100084China

In this paper,a method for analyz.ng the high-frequenc. attenuation property of polyurea-matrix c.mposites is developed by c.mbining experimental,c.mputational and theoretic.l ***,the ultrasonic.experimental platform is established by solving the diffic.lties of high-frequenc. ultrasonic.testing as high-frequenc. signal distortion,insuffic.ent driving voltage and sampling rate failure,to study the dynamic.mec.anic.l properties(1-5 MHz.of pure polyurea and polyurea-matrix ***,the influenc.s of c.mposite parameters inc.uding the siz. and volume frac.ion of inc.usions on wave attenuation performanc. under different frequenc.es are obtained and further verified by numeric.l ***,the c.ntribution of inc.usions to the wave attenuation performanc. is also theoretic.lly *** is found that the inc.ease of inc.usion volume frac.ion and inc.usion diameter will inc.ease the attenuation c.effic.ent of the *** the attenuation of c.mposites with the inc.usions of a 150-μm diameter and 30%as volume frac.ion c.n be 82%higher than pure *** amplifying attenuation effec. of inc.usions is mainly attributed to the sc.ttering effec.,whic. is verified by c.mparing numeric.l and theoretic.l results.

关键词： Polyurea Visc.elastic Dynamic.mec.anic.l properties Ultrasound

Miyaoka-type inequalities for terminal threefolds with nef anti-c.nonic.l divisors

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Sc.enc. c.ina Mathematic. 2025年第1期68卷 1-18页

作者： Masataka Iwai c.en Jiang Haidong liu Department of Mathematic. Graduate School of ScienceOsaka University Shanghai c.nter for Mathematic.l Sc.enc.s & Sc.ool of Mathematic.l Sc.enc.s Fudan University Department of mathematic. Sun Yat-sen University

In this paper,we study Miyaoka-type inequalities on c.ern c.asses of terminal projec.ive 3-folds with nef anti-c.nonic.l *** X be a terminal projec.ive 3-fold suc. that-KXis *** show that if c.（X） · c.（X）≠0,then c.（X） · c.（X） ≥ 1/252;if further X is not rationally c.nnec.ed,then c.（X） · c.（X） ≥ 4/5 and this inequality is *** order to prove this,we give a partial c.assific.tion of suc. varieties along with many *** also study the nonvanishing of c.（X）dim X-2· c.（X） for terminal weak Fano varieties and prove a Miyaoka-Kawamata-type inequality.

关键词： terminal threefolds Miyaoka-type inequality boundedness