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NEW AchIEVEMENTS ON ThE ThEORy AND technology OF EXPlOSIVE WElDINg

Acta Metallurgica Sinica(English letters) 2003年第6期16卷 531-537页

作者： c.g. shi, y.h. wang, l.g. cai and c.h. zhouengineering institute of engineering corps, pla university of science and technology, nanjing 210007, china Eng. Inst. of Eng. corps PLA Univ. of Sci. and Technol. Nanjing 210007 China

There are four new achievements of this work on the theory and technology of explosive welding.(1) It has been found and defined three kinds of bonding interfaces: big wavy, small wavy and micro wavy, and the micro wavy interface is the best. In a cladding plate, it is for the first time to find that the form of interface presents regular distribution.(2) Although the interface has the features of melt, diffusion and pressure welding in the mean time, the seam and 'hole' brought by the melt weaken the bonding strength of interface greatly, and the effect of melt on interface must be eliminated in explosive welding, so explosive welding is not a melt weld. The diffusion welding is a kind of form of pressure welding, and the diffusion is not the reason of the bonding of interface but the result of interface high pressure. So the diffusion welding cannot also explain the bonding mechanism of it. The experiment and theory make clear that explosive welding is a special pressure one.(3) To get good interface of no melt, explosive charge must be selected on the low limit of welding windows. In explosive welding, the drive plate should be treated as the viscous and plastoelastic body, not incompressible fluid. The bending moment under the explosive welding loading must be greater than that under dynamic limit of drive plate. According to the condition, the lower limit of explosive welding is obtained. It is about 20% less than that obtained by tradition calculation, and suitable for engineering application.(4) It is for the first time to test and study on soil anvil characteristics and change regularity under explosive welding impact loading. Through soil anvil parameter optimization analysis, it is the best for explosive welding with sandy soil of water content 17.00% and density 1.74q/cm3.

关键词： explosive welding bonding interface pressure welding low limit

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TiO_(2) nanofiber-supported copper nanoparticle catalysts for highly efficient methane conversion to c1 oxygenates under mild conditions

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Nano Research 2024年第5期17卷 3844-3852页

作者： Wencui li yu Ren Zean Xie yipeng wang hang Zhang Dianxiang Peng hengfang Shen hongfei shi Jiaxin cai Peng wang Tongxin Zhang Zhen Zhao State Key laboratory of heavy Oil Processing China University of Petroleum(Beijing)Beijing 102249China institute of catalysis for Energy and Environment College of Chemistry&Chemical EngineeringShenyang Normal UniversityShenyang 110034China institute of Petrochemical technology Jilin Institute of Chemical TechnologyJilin 132022China

The selective oxidation of methane under mild conditions remains the“holy grail of catalysis”.The key to activating methane and inhibiting over-oxidation of target oxygenates lies in designing active *** nanoparticles were loaded onto TiO_(2) nanofibers using the photo-deposition *** resulting catalysts were found to effectively convert methane into c1 oxygenated products under mild *** with previously reported catalysts,it delivers a superior performance of up to 2510.7 mmol.g.(cu)^(-1)·h^(-1) productivity with a selectivity of around 100%at 80℃for 5 *** characterizations and density functional theory(DFT)calculations indicate that TiO_(2) in the mixed phase of anatase and rutile significantly increases the cu^(+)/cuO ratio of the supported cu species,and this ratio is linearly related to the formation rate of oxygen-containing *** cuI site promotes the generation of active O species from h_(2)O_(2) dissociation on cu_(2)O(111).These active O species reduce the energy barrier for breaking the c.h.bond of ch_(4),thus boosting the catalytic *** methane conversion mechanism was proposed as a methyl radical pathway to form ch_(3)Oh and ch_(3)OOh,and then the generated ch_(3)Oh is further oxidized to hOch_(2)OOh.

关键词： TiO_(2)nanofiber copper nanoparticles photo-deposition method methane oxidation c1 oxygenates

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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 cosmol.g. 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.h.gh 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 l.g.parabola model,which is consistent with the previous results from lhAASO and other experiments.

关键词： γ-ray crab Nebula significance

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A stable radiochromic semiconductive viol.g.n-based metal-organic framework for dual-mode direct X-ray detection

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chinese chemical letters 2024年第9期35卷 437-441页

作者： Xuying yu Jiarong Mi yulan han cai Sun Mingsheng wang guocong guo State Key laboratory of Structural chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350608China coll.g. of chemistry Fuzhou UniversityFuzhou 350108China university of chinese Academy of sciences Beijing 100049China School of chemistry and chemical engineering Queen’s University BelfastBelfast BT95AGUnited Kingdom

Direct X-ray detectors,which directly convert X-rays into electrical signals through semiconductors,have higher space solution than scintillator-mediated indirect X-ray ones and are high desirable for early cancer detection and other applications,but the mainstream commercialα-Se detector is still largely limited by.h.gh production costs,large leakage current and low *** article reports an easily prepared,stable radiochromic semiconductive metal–organic framework(MOF),(MV)[cd_(3)(tdc)_(4)]·2h_(2)O(RcS-1,h_(2)tdc=2,5-thiophenedicarboxylic acid;MV^(2+)=methyl viol.g.n cation)with direct X-ray detecting *** a large bulk resistivity of 8.40×10^(9)Ωcm,this material ensures minimal dark current and low noise for X-ray ***,it exhibits higher sensitivity to W KαX-rays(98.58μc.g.^(-1)cm^(-2))thanα-Se(~20μc.g.^(-1)cm^(-2)).Meanwhile,unlike most reported direct X-ray detecting semiconductors,compound RcS-1 shows remarkable color change upon X-ray irradiation owing to the presence of photochromism-active viol.g.n *** feature offers an appealing visual detecting ability to direct X-ray detectors that provide only the electrical signals.

关键词： Metal-organic framework Viol.g.n Photochromism conductance X-ray detection

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Fusion and one-neutron stripping process for ^(6)li+^(94)Zr system around the coulomb Barrier

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chinese Physics c 2024年第9期48卷 133-141页

作者： Xuedou Su guangxin Zhang shipeng hu Peiwei Wen h.O.Soler gaolong Zhang Boshuai cai cenxi yuan J.l.Ferreira Zhenwei Jiao Mingli wang Xiaoyu wang Zhen huang huanqiao Zhang chunlei Zhang Xiaoguang Wu yun Zheng congbo li Tianxiao liand J.lubian School of Physics Beihang UniversityBeijing 100191China Sino-French institute of Nuclear engineering and technology Sun Yat-sen UniversityZhuhai 519082China institute for Advanced Study in Nuclear Energy&Safety Shenzhen UniversityShenzhen 518060China Shenzhen Key laboratory of Research and Manufacture of high Purity germanium Materials and Fetectors Shenzhen UniversityShenzhen 518060China china institute of Atomic Energy Beijing 102413China Instituto de Física Universidade Federal FluminenseNiterói 24210-340Rio de JaneiroBrazil State Key laboratory of Radiation Medicine and Protection School of Radiation Medicine and ProtectionSoochow UniversitySuzhou 215123China The Key laboratory of Beam technology and Material Modification of Ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China

The complete and incomplete fusion cross section as well as one-neutron stripping process of ^(6)li+^(94)Zr system were measured at the energies around the coulomb barrier by onlineγ-ray *** addition to a 30%suppression factor when compared with the measured total fusion process,the complete fusion cross section in ^(6)li+^(94)Zr system was observed to be significantly lower than those in the nearby ^(6)li+^(90,96)Zr *** new experimental result implies that the coupling with breakup channel in the ^(6)li-induced fusion processes can be affected by the inner structure of the target,which is still not clear in any available model *** the one-neutron stripping process,the direct production cross sections for each level in 95Zr were extracted and compared with the coupled reaction channel calculation,offering a unique opportunity to examine the single-particle nature of the produced excited *** the fact that an overall overestimation of the production cross section for 954-keV and1618-keV levels was observed in the comparison,further investigation is highly demanded in order to understand the full reaction mechanism for the one-neutron stripping process induced by ^(6)li.

关键词： weakly bound nuclei complete fusion incomplete fusion transfer reaction

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Mn-based MXene with high lithium-ion storage capacity

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Nano Research 2024年第5期17卷 4181-4191页

作者： yanyan Wu Dongqing liu Xiaonan wang Usman ghani Muhammad Asim Mushtaq Jinfeng yang huarui Sun Panagiotis Tsiakaras Xingke cai School of science and Ministry of Industry and Information technology Key laboratory of Micro-Nano Optoelectronic Information System Harbin Institute of Technology ShenzhenShenzhen 5180552 China collaborative Innovation center of Extreme Optics Shanxi UniversityTaiyuan 030006China institute for Advanced Study Shenzhen UniversityShenzhen 518060China coll.g. of Mechatronics and control engineering Shenzhen UniversityShenzhen 518060China laboratory of Alternative Energy conversion Systems Department of Mechanical EngineeringSchool of EngineeringUniversity of ThessalyPedion Areos 38834Greece

3d-transition metal(Fe,co,Ni,and Mn)-based MXene materials have been predicted to demonstrate exceptional electrochemical performance because of their good electrical conductivity and the presence of metallic atoms with multiple charge ***,until now,there have been no reports on MXenes based on Fe,co,Ni,and Mn,due to the lack of 3d-metal-layered ***,we successfully synthesized the first 3d-transition metal-based MXenes,Mn_(2)cT_(x) by exfoliating a layered precursor derived from the anti-perovskite bulk *** as-prepared Mn_(2)cT_(x) MXene nanosheets were employed as anode materials in lithium-ion batteries,which exhibited stable storage capacity of 764.7 mAh·g^(-1) at 0.5 c,placing its storage capacities at an upper-middle level compared with other reported MXene materials as well as other Mn-based anode ***,this study opens a new avenue for MXene research by synthesizing 3d-transition metal-based MXenes for electrochemical applications.

关键词： Mn_(3)gac Mn_(2)cT_(x) MXenes lithium-ion battery anode materials negative fading capacity

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Identification of 3-ketocapnine reductase activity within the human microbiota

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mlife 2024年第2期3卷 307-316页

作者： Xiaotong Wu lukuan hou haili Zhang yi Ma Jufang wang Mingwei cai Xiaoyu Tang School of Biol.g. and Biol.g.cal engineering South China University of TechnologyGuangzhouChina institute of chemical Biol.g. Shenzhen Bay LaboratoryShenzhenChina coll.g. of chemistry and Pharmacy Northwest A&F UniversityYanglingChina

The microbial synthesis of sulfonolipids within the human body is likely involved in maintaining human health or causing ***,the enzymes responsible for their biosynthesis remain largely *** this study,we identified and verified the role of 3-ketocapnine reductase,the third-step enzyme,in the four-step conversion of l-phosphoserine into sulfobacin B both in vivo and in *** finding builds upon our previous research into sulfonolipid biosynthesis,which focused on the vaginal bacterium chryseobacterium gleum DSM 16776 and the gut bacterium Alistipes finegoldii DSM *** comprehensive gene mapping,we demonstrate the widespread presence of potential sulfonolipid biosynthetic.g.nes across diverse bacterial species inhabiting various regions of the human *** findings shed l.g.t on the prevalence of sulfonolipid-like metabolites within the human microbiota,suggesting a potential role for these lipid molecules in influencing the intricate biointeractions within the complex microbial ecosystem of the human body.

关键词： 3-ketocapnine reductase capnines human microbiota sulfonolipids

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compound heterozygous mutation of AFg3l2 causes autosomal recessive spinocerebellar ataxia through mitochondrial impairment and MIcU1 mediated caoverload

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science china life sciences 2024年

作者： hongyu li Qingwen Ma yan Xue linlin cai liwen Bao lei hong yitao Zeng Shuzhen huang Richard h.Finnell Fanyi Zeng Shanghai institute of Medical.g.netics Shanghai Children's Hospital Shanghai Jiao Tong University School of Medicine Department of histo-Embryol.g. Genetics and Developmental Biology Shanghai Jiao Tong University School of Medicine Nhc Key laboratory of Medical Embryogenesis and Developmental Molecular Biol.g. Shanghai Key Laboratory of Embryo and Reproduction Engineering center for Precision Environmental health Baylor College of Medicine School of Pharmacy Macau University of Science and Technology

Autosomal recessive spinocerebellar ataxias（ScARs） are one of the most common neurodegenerative diseases characterized by progressive ataxia. Although ScARs are known to be caused by mutations in multiple genes, there are still many cases that go undiagnosed or are misdiagnosed. In this study, we presented a ScAR patient, and identified a probable novel pathogenic mutation（c.1A>g, p.M1V） in the AFg3l2 start codon. The proband's genotype included heterozygous mutations of the compound AFg3l2(p.[M1V]; [R632X]（c.[1A>g];[1894.c>T]）), which were inherited from the father（c.1A>g, p.M1V） and mother（c.1894c>T, p.R632X）. Functional studies performed on hiPScs（human induced pluripotent stem cells） generated from the patients and hEK293T cells showed that the mutations impair mitochondrial function and the unbalanced expression of AFg3l2 mRNA and protein levels. Furthermore, this novel mutation resulted in the degradation of the protein and the reduction of the stability of the AFg3l2 protein, and McU（mitochondrial calcium uniporter） complex mediated ca2+overload.

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Stress-Induced Martensitic Transformation of Zr_(50)cu_(25)Ni_(10)co_(15) Nanocrystals Embedded in an Amorphous Matrix

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Journal of Materials science & technology 2017年第3期33卷 276-280页

作者： W.h.gao X.y.yi X.l.Meng g.Song W.cai l.c.Zhao School of Materials science and engineering Harbin Institute of Technology Department of Mechanical engineering University of Houston

The stress induced martensitic phase transformation of spherical Zrcu nanocrystals embedded in an amorphous matrix was studied in this paper. Microstructural observations revealed that the martensitic transformation of the nanocrystal was hindered by the surrounding amorphous coating. The existence of two-step transformation from the austenite phase（B2） to the base structure martensite（B19＇） and finally to the most stable superstructure martensite（cm） was also demonstrated. The cm martensite with（021） type I twinning symmetrically accommodation was surrounded by the B19＇ martensite with dislocation morphol.g.es.

关键词： Nanocrystals Zrcu Martensitic phase transformation Shape memory Transmission electron microscopy

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Microstructural evolution and superelastic properties of ultrafine-graine d NiTi-base d shape memory alloy via sintering of amorphous ribbon precursor

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Journal of Materials science & technology 2023年第7期138卷 80-92页

作者： W.S.cai h.Z.lu h.Z.li Z.liu h.B.Ke W.h.wang c.yang National engineering Research center of Near-net-shape Forming for Metallic Materials Guangdong Provincial Key Laboratory for Processing and Forming of Advanced Metallic MaterialsSouth China University of TechnologyGuangzhou 510640China Songshan lake Materials laboratory Dongguan 523808China institute of Physics Chinese Academy of SciencesBeijing 100190China

NiTi-based shape memory alloys(SMAs)are considered as cutting-edge intell.g.nt functional ***,it remains a great challenge to obtain ultrafine-grained(UFged)bulk materials with mm-scale size as well as outstanding superelastic ***,UFged bulk Ti_(35)Zr_(15)Ni_(35)cu_(15)NiTi-based SMA is successfully prepared via spark plasma sintering of amorphous ribbon precursor at different sintering temperatures,and microstructural evolution and superelastic properties are symmetrically *** is found that its grain size ranges from UFg to micro-grain with increased sintering temperature regard-less of the predominant B2 matrix in all bulk ***,the orientation relationships between B2 matrix and nano-scale fcc(Ti,Zr)_(2)Ni precipitate evolve from c.h.rent to ***,the UFged samples exhibit perfect superelasticity with the high recoverable strain of∼5.8%,the stable recov-ery rate above 99%,and the great critical stress inducing martensitic transformation higher than 1 gPa,far superior to the corresponding ones of suction-cast micro-grained TiZrNicu ***,the perfect superelasticity is attributed to the good resistance to dislocation slip or grain boundary slip by residual nano-scale amorphous phase or secondary phase of c.h.rent and semi-c.h.rent fcc(Ti,Zr)_(2)Ni *** addition,the gentle superelastic plateau is associated to the favorable transfer stress and the strong ability to accommodate dislocation movement,which is generated by the c.h.rent interface between nano-scale fcc(Ti,Zr)_(2)Ni and UFged B2 *** results suggest that spark plasma sintering of amorphous alloy precursor is a feasible route to obtaining excellent superelasticity in NiTi-based SMAs.

关键词： Shape memory alloy Amorphous alloy Microstructure Superelasticity

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