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Acta Metallurgica Sinica(English Letters) 2008年第3期21卷 205-210页

作者： Q.F. zhu z.H. zhao J.z. Cui Y.b. zuo F. Qu Key Laboratory of Electromagnetic Processing of Materials Ministry of Education Northeastern Univer- sity Shenyang 110004 China

The influences of the low frequency electromagnetic field on the horizontal direct chill casting process were investigated experimentally. Ingots of 2024 aluminum alloy with a cross size of 40 mm× 200 mm were produced by the conventional horizontal chill casting process and low frequency electromagnetic horizontal chill casting processre- spectively. The as-cast structures and the mechanical property of the ingots were examined. The results showed that the low frequency electromagnetic field could sub- stantially refine the microstructures and pronouncedly reduce the macrosegregation in the horizontal direct chill casting process. Moreover, the surface quality of the ingot was prominently improved by the low frequency electromagnetic field. The fracture strength and elongation percentage of the ingot was increased with the low frequency electromagnetic field.

关键词： Horizontal direct chill casting Low frequency electromagnetic field 2024 aluminum alloy Microstructures Macrosegregation

What Can We Learn from the Geoeffectiveness of the Magnetic Cloud on 2012 July 15–17?

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Research in Astronomy and Astrophysics 2022年第1期22卷 14-18页

作者： Gui-ang Liu Ming-Xian zhao Gui-Ming Le Tian Mao School of Physics Science and Technology Lingnan Normal UniversityZhanjiang 524048China Key Laboratory of Solar Activity National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China Key Laboratory of Space Weather National Center for Space WeatherChina Meteorological AdministrationBeijing100081China

An interplanetary shock and a magnetic cloud(MC) reached the Earth on 2012 July 14 and 15 one after *** shock sheath and the MC triggered an intense geomagnetic *** find that only small part of the MC from06:45 UT to 10:05 UT on 2012 July 15 made contribution to the intense geomagnetic storm,while the rest part of the MC made no contribution to the intense geomagnetic *** averaged southward component of interplanetary magnetic field(bs) and duskward-electric fields(Ey) within the MC from 10:05 UT,2012 July 15 to09:08 UT,2012 July 16(hereafter MC2),are 15.11 nT and 8.01 my m-1,*** to the empirical formula established by burton et al.(hereafter burton equation),the geoeffectiveness of MC2 should be-655.42 nT,while the geoeffectiveness of MC2 is-324.68 nT according to the empirical formula established by O’brien & McPherron(hereafter OM equation).However,the real geoeffectiveness of MC2 is 39.74 *** results indicate that the burton equation and the OM equation cannot work *** geoeffectiveness of MC2 shows that large and long duration of bs or Ey cannot guarantee the occurrence of an intense geomagnetic storm if the solar wind dynamic pressure is very *** we use 0.52 as γ,the geoeffectiveness of MC2 is 40.36 nT according to the empirical formula established by Wang et al.,which is very close to the observed value,indicating that the empirical formula established by Wang et *** much better than the burton equation and the OM equation.

关键词： Solar coronal mass ejections Solar-terrestrial interactions Solar wind

Distribution of pericellular matrix molecules in the temporomandibular joint and their chondroprotective effects against inflammation

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International Journal of Oral Science 2017年第1期9卷 43-52页

作者： Wern Cui Chu Shipin zhang Timothy J Sng Yu Jie Ong Wen-Li Tan Vivien Y ang Casper b Foldager Wei Seong Toh Faculty of Dentistry National University of SingaporeSingapore Orthopaedic Research Laboratory Aarhus University HospitalAarhusDenmark Tissue Engineering Program Life Sciences InstituteNational University of SingaporeSingapore

The objectives of this study were to （1） determine the distribution and synthesis of pericellular matrix （PCM） molecules （collagen VI, collagen IV and laminin） in rat temporomandibular joint （TMJ） and （2） investigate the effects of PCM molecules on chondrocytes against inflammation in osteoarthritis. Four zones （fibrous, proliferating, mature and hypertrophic） of condylar cartilage and three bands （anterior, intermediate and posterior） of disc were analysed by immunohistochemistry for the presence of PCM molecules in rat TMJs. Isolated chondrocytes were pre-treated with PCM molecules before being subjected to interleukin （IL）-II~ treatment to stimulate inflammation. The responses of the chondrocytes were analysed using gene expression, nitric oxide release and matrix metalloproteinase （MMP）-13 production measures. Histomorphometric analyses revealed that the highest areal deposition of collagen VI （67.4%）, collagen IV （45.7%） and laminin （52.4%） was in the proliferating zone of TMJ condylar cartilage. No significant difference in the distribution of PCM molecules was noted among the three bands of the TMJ disc. All three PCM molecules were expressed intracellularly by chondrocytes cultured in the monolayer. Among the PCM molecules, pre-treatment with collagen VI enhanced cellular proliferation, ameliorated IL-lp-induced MMP-3, MMP-9, MMP-13 and inducible nitric oxide synthase gene expression, and attenuated the downregulation of cartilage matrix genes, including collagen I, aggrecan and cartilage oligomeric matrix protein （COMP）. Concurrently, collagen VI pretreatment inhibited nitric oxide and MMP-13 production. Our study demonstrates for the first time the distribution and role of PCM molecules, particularly collagen VI, in the protection of chondrocytes against inflammation.

关键词： cartilage chondrocytes collagen iV collagen W inflammation laminin pericellular matrix temporomandibular joint

SOLUTION TREATMENT EFFECTS IN CObALT-NICKEL SECONDARY HARDENING STEEL

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Acta Metallurgica Sinica(English Letters) 1996年第6期9卷 613-618页

作者： P. zhong b. Ling and b.z. Gu(beijing Institute of Aeronautical Materials, beijing 100095, beijing Inst of Aeronautical materials Beijing China

Effect of the austenitizing temperature on the microstructure,strength, and toughness of 16NiCo and 23NiCo alloys was studied. With increasing austenitizing temperature, the reductions in strength and hardness are probably caused by the coarsening of M_2C carbides. The use of higher austenitizing temperature resulted in improved impact toughness due to the dissolution of undissolved (Cr, Fe, Mo)_(23)C_6 *** the austenitizing temperature is increased to 1050℃ for 16NiCo and 23NiCo alloys impact toughness levels are reduced on average by 31 and 53 J/cm￣2 *** use of 1050℃ austenitizing temperatures resulted in intergranular fracture for 23NiCo alloy in 482℃ aged condition. It was suggested that this grain boundary embrittlement was the result of the formation of cementite particles during ageing.

关键词： secondary hardening ultrahigh strength steel austenitizing temPerature

不同陶瓷颗粒表面处理对陶瓷/高铬铸铁复合材料微观界面的影响

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热加工工艺 2024年第5期53卷 142-146页

作者：汪勇余申卫刘春溪魏昂王成辉王惠梅中国船舶集团有限公司第十二研究所陕西兴平713102

采用传统的高铬铸铁制备电厂用磨煤机磨辊、磨盘已无法满足耐磨需求,陶瓷颗粒增强金属基耐磨复合材料成为替代传统耐磨材料的首选。本文研究了镀镍、镀钛表面处理对陶瓷/高铬铸铁复合材料微观界面的影响。结果表明,表面处理后陶瓷与高... 详细信息

采用传统的高铬铸铁制备电厂用磨煤机磨辊、磨盘已无法满足耐磨需求,陶瓷颗粒增强金属基耐磨复合材料成为替代传统耐磨材料的首选。本文研究了镀镍、镀钛表面处理对陶瓷/高铬铸铁复合材料微观界面的影响。结果表明,表面处理后陶瓷与高铬铸铁界面润湿性改善,可获得较好的铸渗效果。镀镍陶瓷颗粒与高铬铸铁复合材料没有明显的中间过渡层,二者之间的结合强度不高,陶瓷与高铬铸铁结合为机械结合。镀钛陶瓷颗粒与高铬铸铁复合材料的界面由于Ti元素的作用发生化学反应,形成明显的中间过渡层,界面结合强度高,陶瓷与高铬铸铁结合为冶金结合。

关键词：镀镍镀钛 zTA陶瓷高铬铸铁界面结合

Novel infrared differential optical absorption spectroscopy remote sensing system to measure carbon dioxide emission

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Chinese Physics b 2019年第1期28卷 353-359页

作者： Ru-Wen Wang Pin-Hua Xie Jin Xu ang Li Key Laboratory of Environmental Optics and Technology Anhui Institute of Optics and Fine MechanicsChinese Academy of Sciences University of Science and Technology of China CAS Center for Excellence in Urban Atmospheric Environment Institute of Urban Environment Chinese Academy of Sciences

A CO_2 infrared remote sensing system based on the algorithm of weighting function modified differential optical absorption spectroscopy(WFM-DOAS) is developed for measuring CO_2 emissions from pollution sources. The system is composed of a spectrometer with band from 900 nm to 1700 nm, a telescope with a field of view of 1.12?, a silica optical fiber, an automatic position adjuster, and the data acquisition and processing module. The performance is discussed,including the electronic noise of the charge-coupled device(CCD), the spectral shift, and detection limits. The resolution of the spectrometer is 0.4 nm, the detection limit is 8.5 × 10^(20)molecules·cm^(-2), and the relative retrieval error is bution of CO_2 from the plume was obtained. The retrieved differential slant column densities(dSCDs)of CO_2 are around 2 × 10^(21) molecules·cm^(-2) in the unpolluted areas, 5.5 × 10^(21)molecules·cm^(-2) in the plume locations most strongly affected by local CO_2 emissions, and the fitting error is less than 2 × 10^(20)molecules·cm^(-2), which proves that the infrared remote sensing system has the characteristics of fast response and high precision, suitable for measuring CO_2 emission from the sources.

关键词： weighting function modified differential optical absorption spectroscopy(WFM-DOAS) infrared instrument CO2 emission sources

Optimization of performance of the KM2A full array using the Crab Nebula

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Chinese Physics C 2024年第6期48卷 169-178页

作者：曹臻 F.Aharonian 安琪阿西克古白云翔包逸炜 D.bastieri 毕效军毕玉江蔡金庭曹晴曹文羽曹喆常进常劲帆陈尚明陈恩生陈亮陈林陈龙陈明君陈玛丽陈起辉陈素弘陈天禄陈阳程宁程耀东崔明阳崔树旺崔晓红崔昱东戴本忠代洪亮戴子高单增罗布 D.della Volpe 董绪强段凯凯樊军辉范一中方军方堃冯存峰封莉冯少辉丰晓婷冯有亮 S.Gabici 高博高川东高林青高启高卫高伟康葛茂茂耿利斯 G.Giacinti 龚光华苟全补顾旻皓郭福来郭晓磊郭义庆郭莹莹韩毅昂何会海贺昊宁何佳银何新波何钰 M.Heller 贺远强侯博文侯超侯贤胡红波胡铨胡世聪黄代绘黄天奇黄文俊黄性涛黄晓渊黄勇黄志成季筱璐贾焕玉贾康江琨姜晓巍姜泽军金敏康明铭柯通 D.Kuleshov.K.Kurinov 李兵兵李澄李骢李丹李飞李海波李会财李华阳李军李剑李捷李凯李文龙李文莲李秀荣李昕李一卓李哲黎卓梁恩维梁云峰林苏杰刘冰刘成刘栋刘虎刘海东刘佳刘江来刘金艳刘茂元柳若愚刘四明刘伟刘怡刘以农鲁睿罗晴吕洪魁马伯强马玲玲马欣华毛基荣闵振 W.Mitthumsiri 穆慧君南云程 A.Neronov 区子维庞彬宇 P.Pattarakijwanich 裴致远齐孟尧祁业情乔冰强秦家军 D.Ruffolo A.Sáiz D.Semikoz 邵澄宇邵琅 O.Shchegolev 盛祥东舒富文宋慧超 Yu.V.Stenkin V.Stepanov 苏扬孙秦宁孙晓娜孙志斌谭柏轩唐庆文唐泽波田文武王超王昌贝王广威王洪光王惠惠王建成汪凯王利苹王玲玉王培汉王冉王为王祥高王祥玉王阳王玉东王岩谨王忠海王仲翔王振王铮韦大明魏俊杰魏永健文韬吴超勇吴含荣武莎吴雪峰吴雨生席邵强夏捷夏君集项光漫肖迪泫肖刚辛广广辛玉良邢祎熊峥徐东莲徐仁峰徐仁新徐伟立薛良闫大海颜景志颜田杨朝文杨帆杨冯帆杨何文杨佳盈杨莉莉杨明洁杨睿智杨深邦姚玉华姚志国叶一锰尹丽巧尹娜游晓浩游智勇于艳红袁强岳华曾厚敦曾婷轩曾玮查敏张彬彬张丰张海明张恒英张建立张丽霞张力张鹏飞张佩佩张瑞张少博张少如张寿山张潇张笑鹏张云峰张毅张勇赵兵赵静赵雷赵立志赵世平郑福周斌周浩周佳能周猛周平周荣周勋秀祝成光祝凤荣朱辉朱科军左雄 LHAASO Collaboration Key Laboratory of Particle Astrophyics&Experimental Physics Division&Computing Center Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China Tianfu Cosmic Ray Research Center Chengdu 610000China Dublin Institute for Advanced Studies 31 Fitzwilliam Place2 DublinIreland Max-Planck-Institut for Nuclear Physics P.O.Box 10398069029 HeidelbergGermany State Key Laboratory of Particle Detection and Electronics China University of Science and Technology of China Hefei 230026China School of Physical Science and Technology&School of Information Science and Technology Southwest Jiaotong UniversityChengdu 610031China School of Astronomy and Space Science Nanjing UniversityNanjing 210023China Center for Astrophysics Guangzhou UniversityGuangzhou 510006China Hebei Normal University Shijiazhuang 050024China Key Laboratory of Dark Matter and Space Astronomy&Key Laboratory of Radio Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210023China Tsung-Dao Lee Institute&School of Physics and Astronomy Shanghai Jiao Tong UniversityShanghai 200240China Key Laboratory for Research in Galaxies and Cosmology Shanghai Astronomical ObservatoryChinese Academy of SciencesShanghai 200030China Key Laboratory of Cosmic Rays(Tibet University) Ministry of EducationLhasa 850000TibetChina National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China School of Physics and Astronomy(zhuhai)&School of Physics(Guangzhou)&Sino-French Institute of Nuclear Engineering and Technology(zhuhai) Sun Yat-sen UniversityZhuhai 519000&Guangzhou 510275China School of Physics and Astronomy Yunnan UniversityKunming 650091China Département de Physique Nucléaire et Corpusculaire Facultéde SciencesUniversitéde Genève24 Quai Ernest Ansermet1211 GenevaSwitzerland Institute of Frontier and Interdisciplinary Science Shandong UniversityQingdao 266237China APC Universit'e Paris Cit'eCNRS/IN2P3CEA/IRFUObservat

The full array of the Large High Altitude Air Shower Observatory(LHAASO)has been in operation since July *** its kilometer-square array(KM2A),we optimized the selection criteria for very high and ultrahigh energyγ-rays using data collected from August 2021 to August 2022,resulting in an improvement in significance of the detection in the Crab Nebula of approximately 15%,compared with that of previous *** the implementation of these new selection criteria,the angular resolution was also significantly improved by approximately 10%at tens of *** aspects of the full KM2A array performance,such as the pointing error,were also calibrated using the Crab *** resulting energy spectrum of the Crab Nebula in the energy range of 10-1000 TeV are well fitted by a log-parabola model,which is consistent with the previous results from LHAASO and other experiments.

关键词： γ-ray Crab Nebula significance

Extended Phase Space in the Framework of Holography

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Communications in Theoretical Physics 2019年第5期71卷 590-598页

作者： z.Sherkatghanad b.Mirza H.Nadi M.Rostami Department of Physics Isfahan University of Technology

We consider a holographic extended phase space in the presence of Reissner-Nordstrom-Anti-de Sitter(RNAdS) and born-Infeld-Anti-de Sitter(bI-AdS) black holes in the bulk. In this extended phase space the cosmological constant is investigated as pressure and volume is defined as the codimension one-time slice in the bulk geometry enclosed by the minimal area appearing in the computation of the holographic entanglement entropy. These thermodynamics quantities can serve as probes of the underlying phase transition dictated by black hole thermodynamics, but do not describe different structures. We find that the isocharges on the pressure-volume plane exhibit a Van der Waals-like structure, for RN-AdS black holes in the background. For bI-AdS black holes, we observe the analogy with a Van der Waals liquid-gas system for βQ > 1/2 and Reentrant phase transition for βQ behavior is observed when we use the fidelity susceptibility as the volume and the cosmological constant as the pressure for RN-AdS black hole in the background.

关键词： extended phase space holography entanglement entropy phase cosmology

MODELING AND EXPERIMENTAL RESEARCH OF FOUR-STRAND LOW-FREQUENCY ELECTROMAGNETIC CASTING ALUMINUM ALLOY

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Acta Metallurgica Sinica(English Letters) 2007年第3期20卷 157-166页

作者： J.C. Li b.F. Wang J.z. Cui School of Materials ＆ Metallurgy Inner Mongolia University of Science and Technology Baotou 014010 China The Key Laboratory of Electromagnetic Processing of Materials Ministry of Education Northeastern University Shenyang 110004 China

With the aid of ANSYS software, the effect of different mould external part materials on magnetic flux density in the aluminum melt and magnetic field interaction of four coils applied with same currents were investigated. Calculating results showed that magnetic flux density in the aluminum melt was greatly improved and the magnetic field interaction among different coils was decreased when external part of mould is made of soft magnetic material. based on the finding, a four-strand low-frequency electromagnetic casting 6063 aluminum alloy experiment was carried out in the laboratory . The experiment showed that the surface of the billet was smooth and had no exudations and cold shuts, the as-cast microstructures were fine, uniform, equiaxed, net-globular or globular under low-frequency electromagnetic field. The microstructure becomes finer with increased current value.

关键词： low-frequency electromagnetic casting finite element method aluminum alloy mould

Controls on migration and aggregation for tectonically sensitive elements in tectonically deformed coal:An example from the Haizi mine, Huaibei coalfield, China

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Science China Earth Sciences 2014年第11期57卷 1180-1191页

作者： LI Yunbo JIang bo QU zhengHui School of Resource and Earth Science China University of Mining & Technology Key Laboratory of Coalbed Methane Resources and Reservoir-Forming Ministry of Education

Tectonically deformed coal(TDC)develops because of the superimposed deformation and metamorphism of a coal seam by tectonic *** migration and accumulation of trace elements in TDC is largely in response to stress-strain *** develop a law governing the migration and aggregation of sensitive elements and investigate the geological controls on TDC,coal samples from different deformation sequences were collected from the Haizi mine,in the Huaibei coalfield in Anhui Province,China,and the concentrations of 49 elements were determined by XRF and ICP-MS,and then microscopically *** results show that the distribution and morphology of minerals in coal is related to the deformation degree of *** evolutionary process runs from orderly distribution of minerals in a weak brittle deformed coal to disordered distributions in ductile deformed *** to the elemental distribution characteristics in TDC,four types of element migration can be identified:stable,aggregate,declining,and undulate types,which are closely related to the deformation degree of *** data indicate that the overall distribution of rare earth elements(REE)does not change with metamorphism and deformation,but it shows obvious dynamic differentiation phenomena along with the deformation of *** action after coal-formation,brittle or ductile deformation,and the metamorphic mechanism and its accompanying dynamic thermal effects are the main factors that influence the redistribution of elements in *** conclude that tectonic movements provide the motivation and basis for the redistribution of elements and the paths and modes of element migration are controlled by brittle and ductile deformation metamorphic *** dynamic thermal effect has the most significant effect on coal metamorphism and tectonic-stress-accelerated element migration and *** factors then induce the tectonic-dynamic differentiation phenomenon of element migration.

关键词： tectonically deformed coal sensitive elements migration and aggregation law geological controlling factors Haizi mine