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Stationary Photorefractive Self-Pump Phase-Conjugation with Stimulated Backward Scattering in LinbO_(3):Fe Crystals

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Chinese Physics Letters 1999年第1期16卷 29-31页

作者： XU Jing-jun.zhang Xin-zheng SUn Qian.zhang Guo-quan n.Kamber LIU Si-min.zhang Guang-yin Photonics Research Center College of Physical ScienceNankai UniversityTianjin 300071

Stationary photorefractive self-pumped phase-conjugation with one four-wave-mixing interaction region,stimulated by the photorefractive amplified backward scattering,is obtained in LinbO3:Fe crystals,in which the strong backward scattered light is gotten by putting a scattering particle on the backface of the *** though its reflectivities are not high(its temporal and stationary reflectivities are 10%and 3%,respectively),due to the low electrooptic coefficients of LinbO3:Fe crystals,our experimental results prove that this mechanism is effective and simple comparing with the“cat”self-pumped phase-conjugator.

关键词： scattering pumped Photorefractive

Differential Geochemical Features of Clinopyroxene from the Floodplain Sediments in Yangtze and Hanjiang Rivers and Its Implication for Detrital Source Identification

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Journal of Earth Science 2014年第4期25卷 638-647页

作者： Jian Yang Chang'an Li Yufen.zhang n'dji dit Jacques Dembele Faculty of Earth Sciences China University of Geosciences Key Laboratory of Biogeology and Envirnmental Geology of Ministry of Educations China University of Geosciences Institute of Geophysics and Geomatics China University of Geosciences

The evolution history of the Yangtze River attracted increasing attention in recent years. Comparison of the properties of the floodplain sediments between the upper and lower reaches of the Three Gorges is of significance to identify the material detrital sources for the Yangtze River Basin. Clinopyroxene （Cpx） is the typical mineral widely distributed in the sediments of the Yangtze River Ba- sin. Cpx was extracted from the fine sediments with the grain size ranging from 0.063 to 0.125 mm in the upper and lower reaches of the Three Gorges. The sediments, from which the Cpx was extracted, were taken from the floodplains of the catchments of both the Yangtze River and the Hanjiang River, as well as from the surface of the Zhoulao Core drilled in the center of the Jianghan Basin where the two rivers flow through. Geochemistry of these Cpx was investigated, concerning the contents of major elements measured by electron probe microanalysis （EPMA） and the contents of trace elements analyzed by laser ablation inductively coupled plasma-mass spectrometry （LA-ICP-MS）. The Cpx in the Yangtze River contains titaniferous augite which is sourced from the Panzhihua-Xichang region in South Sichuan Province, whereas the Cpx in the Hanjiang River is mainly from the surroundings without any titanif- erous augite. The REE analysis infers that the titaniferous augite is the diagnostic mineral of the upper Yangtze River, and thus could be used as a tracer mineral to identify the detrital sources for the sedi- ments formed during the evolution of the Yangtze River. The Cpx from the surface sediments of the Jianghan Plain （Zhoulao Core） shows comparable geochemical nature with that of the Yangtze River, but is different in geochemistry from that of the Hanjiang River, implying that the modern sediments in the Jianghan Plain are mainly sourced from the upper Yangtze River.

关键词： provenance Yangtze River Hanjiang River clinopyroxene EPMA LA-ICP-MS geochemistry.

natural killer cell-triggered vascular transformation:maternal care before birth?

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Cellular & Molecular Immunology 2011年第1期8卷 1-11页

作者： Jianhong zhang Zhilin Chen Graeme n Smith B.Anne Croy Department of Anatomy and Cell Biology Queen’s UniversityKingstonONCanada Department of Obstetrics and Gynecology Queen’s UniversityKingstonONCanada

natural killer(nK)cells are found in lymphoid and non-lymphoid *** addition to important roles in immune surveillance,some nK cells contribute to angiogenesis and circulatory *** uterus of early pregnancy is a non-lymphoid organ enriched in nK cells that are specifically recruited to placental attachment *** species with invasive hemochorial placentation,these uterine natural killer(unK)cells,via secretion of cytokines,chemokines,mucins,enzymes and angiogenic growth factors,contribute to the physiological change of mesometrial endometrium into the unique stromal environment called decidua *** humans,unK cells have the phenotype CD56^(bright) CD16^(dim) and they appear in great abundance in the late secretory phase of the menstrual cycle and early *** expression studies indicate that CD56^(bright) CD16^(dim) uterine and circulating cells are functionally *** humans but not mice or other species with post-implantation decidualization,unK cells may contribute to blastocyst implantation and are of interest as therapeutic targets in female *** and genetic studies in mice first identified triggering of the process of gestation spiral arterial modification as a major unK cell function,achieved via interferon(IFn)-c *** spiral arterial modification,branches from the uterine artery that traverse the endometrium/decidua transiently lose their muscular coat and ability to *** expression of vascular markers changes from arterial to venous as these vessels dilate and become low-resistance,high-volume *** understanding of the vascular interactions of human unK cells is difficult to obtain because endometrial time-course studies are not possible in pregnant *** we briefly review key information concerning unK cell functions from studies in rodents,summarize highlights concerning human unK cells and describe our preliminary studies on development of a humanized,pregnant

关键词： decidua humanized mice pregnancy uterine natural killer cell

Tunnel effects on ring road traffic flow based on an urgent-gentle class traffic model

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Theoretical & Applied Mechanics Letters 2021年第4期11卷 230-235页

作者： Yongliang zhang M.n.Smirnova Jian Ma n.n.Smirnov Zuojin Zhu Faculty of Engineering Science University of Science and Technology of ChinaHefei 230026China Faculty of Mechanics and Mathematics Lomonosov Moscow State UniversityMoscow 119992Russian Federation Moscow Center for Fundamental and Applied Mathematics Moscow 119992Russian Federation Scientific Research Institute for System Analysis Russian Academy of SciencesMoscow 119992Russian Federation naval Architecture and Civil Engineering Jiangsu University of Science and TechnologyZhenjiang 215600China

To explore tunnel effects on ring road traffic flow,a macroscopic urgent-gentle class traffic model is put *** model identifies vehicles with urgent and gentle classes,chooses the tunnel speed limit as free flow speed to express the fundamental diagram in the tunnel,and adopts algebraic expressions to describe traffic pressure and sound *** two speed trajectories at the Kobotoke tunnel in Japan,the model is validated,with good agreement with observed *** results indicate that in the case of having no ramp effects,tunnel mean travel time is almost constant dependent on tunnel *** initial density normalized by jam density is above a threshold of about 0.21,a traffic shock wave originates at the tunnel entrance and propagates *** a threshold drops slightly as a result of on-ramp merging effect,the mean travel time drops as off-ramp diversion effect intensifies *** findings deepen the understanding of tunnel effects on traffic flow in reality.

关键词： Tunnel effects Travel time Density threshold Ramp effects

Detection of DC series arc in more electric aircraft power system based on optical spectrometry

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High Voltage 2020年第1期5卷 24-29页

作者： Jun Jiang Mingxin Zhao Zhe Wen Chaohai zhang Ricardo Albarracín Center for More Electric Aircraft Power System Nanjing University of Aeronautics and AstronauticsNanjing 211106People's Republic of China Departamento de Ingeniería Eléctrica ElectrónicaAutomática y Física AplicadaEscuela Técnica Superior de Ingeniería y Diseño IndustrialUniversidad Politécnica de MadridRonda de Valencia 328012 MadridSpain

Series arcing faults have been recognised as a hazardous phenomenon in the power system of more electric aircraft(MEA),especially with the increasing voltage level and power *** of the electrical method,the optical method can be used as an approach to detect arc fault with the advantages of fast response and immunity to electromagnetic *** is the basis of optical arc detection to determine the distribution spectrum range of direct current(DC)arc *** at series arc optical detection in the MEA DC system,a DC series arc test platform was established to measure the series arc *** spectrum was disassembled though empirical mode decomposition to extract characteristic wavelengths of arc light and denoised by means of wavelet decomposition and reconstruction(wavelet transformation)to reduce equipment *** resolve the baseline drift,the baseline of the arc spectrum measured was calculated and corrected based on Savitzky−*** experimental results indicate that there are several series arc characteristic spectra of the MEA DC system,including 309.3 and 324.5 nm in the ultraviolet ***,the arc spectrum with different metals,copper and aluminium,were contrasted,indicating the arc spectral behaviour is related to the melting/boiling point and chemical properties of the anode *** measurement of the series arc spectrum makes it more effective to apply optical detection in the MEA discharging faults diagnosis.

关键词： power system series

CO_(2)emission evaluation and cost analysis of oxygen blast furnace process with sintering flue gas injection

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Journal of Iron and Steel Research International 2024年第9期31卷 2101-2109页

作者： Wei zhang Jia-meng Lei Jing-qi Li Guo-jun Ma Henrik Saxén The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan430081HubeiChina Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education Wuhan University of Science and TechnologyWuhan430081HubeiChina Process and Systems Engineering Laboratory Faculty of Science and EngineeringÅbo Akademi UniversityÅbo20500Finland

In order to achieve ultra-low emissions of SO_(2)and nO_(x),the oxygen blast furnace with sintering flue gas injection is presented as a promising novel *** CO_(2)emission was examined,and a cost analysis of the process was *** results show that in the cases when the top gas is not circulated(Cases 1–3),and the volume of injected sintering flue gas per ton of hot metal is below about 1250 m^(3),the total CO_(2)emissions decrease first and then increase as the oxygen content of the blast *** the volume of injected sintering flue gas per ton of hot metal exceeds approximately 1250 m^(3),the total CO_(2)emissions gradually *** the recirculating top gas and the vacuum pressure swing adsorption are considered,the benefits of recovered gas can make the ironmaking cost close to or even lower than that of the ordinary blast ***,the implementation of this approach leads to a substantial reduction in total CO_(2)emissions,with reductions of 69.13%(Case 4),70.60%(Case 5),and 71.07%(Case 6),*** integrating previous research and current findings,the reasonable oxygen blast furnace with sintering flue gas injection can not only realize desulfurization and denitrification,but also achieve the goal of reducing CO_(2)emissions and ironmaking cost.

关键词： Oxygen blast furnace Sintering flue gas CO_(2)emission Ironmaking cost

Comparing hydrogen embrittlement behaviors of two press hardening steels:2 GPa vs.1.5 GPa grade

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Journal of Materials Science & Technology 2022年第29期124卷 109-115页

作者： Z.H.Cao B.n.zhang M.X.Huang Department of Mechanical Engineering The University of Hong KongPokfulam RoadHong KongChina

*** The pursuit of advanced high-strength steels(AHSS)has been rising for the automobile industry to build lightweight and fuelefficient vehicles without compromising crashworthiness[1,2].The group of press hardening steels(PHS)is an excellent candidate that comprises high strength,high toughness,and good formability,which are optimal to build intrusion resistant components such as(ⅰ)A/B-pillar reinforcements,(ⅱ)bumper and door beams.

关键词： strength toughness steels

Laser-induced oxidation assisted micro milling of high aspect ratio microgroove on WC-Co cemented carbide

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Chinese Journal of Aeronautics 2021年第4期34卷 465-475页

作者： Guolong ZHAO Hongjun XIA Yang zhang Liang LI ning HE Hans nφrgaard HAnSEn national Key Laboratory of Science and Technology on Helicopter Transmission Nanjing University of Aeronautics and AstronauticsNanjing 210016China Department of Mechanical Engineering Technical University of DenmarkKgs.Lyngby 2800Denmark

Severe tool wear and poor surface quality are the main problems during micro machining of cemented *** this work,an innovative hybrid process of laser-induced oxidation assisted micro milling(LOMM)was proposed to solve the problems.A nanosecond laser was utilized to induce oxidation of the WC-20%Co material,producing loose oxide which was easy to *** micro machinability of the material was improved by laser-induced *** oxidation mechanisms of cemented carbide were studied.A microgroove with a depth of 2.5 mm and aspect ratio of 5 was fabricated *** milling force,surface quality and tool wear mechanisms were *** comparison,a microgroove was also fabricated with conventional micro milling(COMM)using identical milling *** revealed that in LOMM the milling force and tool wear rate were extremely low during removing the *** machined surface quality and dimensional accuracy achieved by LOMM were superior to those obtained by *** surface roughness Saof the microgroove bottom reached 88 nm in LOMM,while the cross-sectional geometry of the microgroove was a *** of the microgroove sidewall machined by LOMM was better than that by *** tool wear forms in LOMM were coating spalling and slight tool nose *** with COMM,the tool life in LOMM was prolonged *** indicates that the proposed hybrid process is an effective and efficient way to fabricate high aspect ratio micro-features with high dimensional accuracy.

关键词： Cemented carbide High aspect ratio Laser-induced oxidation Micro milling Microgroove Tool wear

Evolution of ionization waves in a multi-pulsed plasma jet:the role of memory charges

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Plasma Science and Technology 2023年第3期25卷 95-103页

作者： n Yu BABAEVA G V nAIDIS V F TARASEnKO D A SOROKIn Cheng zhang Tao SHAO Joint Institute for High Temperatures Russian Academy of Sciences Institute of High Current Electronics Siberian BranchRussian Academy of Sciences Institute of Electrical Engineering Chinese Academy of Sciences University of Chinese Academy of Sciences

In this paper,we discuss the properties of ionization waves(IWs)in a multi-pulsed plasma jet while using the two-dimensional computational *** IWs are generated by application of three short negative pulses with a repetition frequency 12.5 *** simulations are performed continuously during a single run while accounting for charges accumulated inside(surface charges)and outside(space charges)the *** plasma forming gas mixture(He/O2=99.8%/0.2%)is injected through the discharge tube into the surrounding humid *** show that an IW can emerge from the tube exit at a pulse rising edge(as a negative IW)and at a falling edge of the same pulse(as a positive IW).It is demonstrated that remnants of the negative and positive charges play an essential role in the discharge *** first pulse travels the shortest distance as it propagates through the initially non-ionized *** IWs developing during the second pulse essentially enlarge the plasma plume *** the same time,the IWs generated by the third pulse eventually decay due to the remnants of charges accumulated during the previous *** memory charges can lead to the IW extinction.

关键词： helium plasma jet multiple pulses positive and negative ionization waves