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Applied Mathematics and Mechanics(English Edition) 2015年第8期36卷 1017-1032页

作者： Demin ZHAO Jianlin LIU c.q.WU Department of Mechanics College of Pipeline and Civil Engineering China University of Petroleum Department of Mechanical and Manufacturing Engineering University of Manitoba

The parametric excited vibration of a pipe under thermal loading may occur because the fluid is often transported heatedly. The effects of thermal loading on the pipe stability and local bifurcations have rarely been studied. The stability and the local bifurcations of the lateral parametric resonance of the pipe induced by the pulsating fluid velocity and the thermal loading are studied. A mathematical model for a simply supported pipe is developed according to the Hamilton principle. Two partial differential equations describing the lateral and longitudinal vibration are obtained. The singularity theory is utilized to anMyze the stability and the bifurcation of the system solutions. The transition sets and the bifurcation diagrams are obtained both in the unfolding parameter space and the physical parameter space, which can reveal the relationship between the thermal field parameter and the dynamic behaviors of the pipe. The frequency response and the relationship between the critical thermal rate and the pulsating fluid velocity are obtained. The numerical results demonstrate the accuracy of the single-mode expansion of the solution and the stability and local bifurcation analyses. It also confirms the existence of the chaos. The presented work can provide valuable information for the design of the pipeline and the controllers to prevent the structural instability.

关键词： thermal load parameter excited local bifurcation,unfolding parameterspace physical parameter space

青藏高原及其周边二叠纪综合地层、生物群以及古地理和古气候演化

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中国科学：地球科学 2024年第4期54卷 1125-1170页

作者：沈树忠张以春袁东勋徐海鹏琚琦张华郑全锋罗茂侯章帅南京大学地球科学与工程学院内生金属矿床成矿机制研究国家重点实验室关键地球物质循环前沿科学中心南京210023 中国科学院南京地质古生物研究所现代古生物学和地层学国家重点实验室南京210008 中国科学院大学南京学院南京210049 中国矿业大学资源与地球科学学院徐州221116

二叠纪是青藏高原各块体演化的关键时段,发生了一系列重大地质和生物事件,当时横跨南北半球统一的泛大陆演化到了鼎盛阶段,阻断了全球东西向的赤道暖流的同时,在泛大陆的东侧形成了一个半封闭的、具有重要历史意义的特提斯洋暖池,是古-... 详细信息

二叠纪是青藏高原各块体演化的关键时段,发生了一系列重大地质和生物事件,当时横跨南北半球统一的泛大陆演化到了鼎盛阶段,阻断了全球东西向的赤道暖流的同时,在泛大陆的东侧形成了一个半封闭的、具有重要历史意义的特提斯洋暖池,是古-中生代之交生物与环境演变的引擎.青藏高原二叠纪地层分布广泛、化石丰富,从南到北由于跨越不同的纬度带体现出不同的特点.雅鲁藏布江以南的喜马拉雅特提斯带当时位于冈瓦纳大陆印度板块北缘,整个二叠纪沉积含有典型的冈瓦纳冷水型生物群;雅鲁藏布江缝合带内的灰岩外来体时代集中在瓜德鲁普世(guadalupian,中二叠世)中、晚期至早三叠世,古生物地理与喜马拉雅特提斯带有显著差异,最有可能为新特提斯洋中的海山型沉积.基墨里(cimmerian)微地块群在乌拉尔世(cisuralian,早二叠世)早期阿瑟尔期-萨克马尔期(Asselian-Sakmarian)全部位于冈瓦纳大陆北缘,均发育冰海相沉积及冈瓦纳型冷水生物群.乌拉尔世中期(约290~280Ma)基墨里微地块群由于印度板块北缘Panjal Traps等大火成岩省岩浆活动与冈瓦纳大陆裂解,并以不同的速度向北漂移.可以分为两个条带,由南羌塘、保山和Sibuma地块组成的北基墨里微地块群漂移速度较快,在亚丁斯克期(Artinskian)就已经出现大量碳酸盐岩沉积和暖水生物群,因此,它们最先从冈瓦纳大陆裂解并进入低纬度暖水区域;而由拉萨、腾冲和Irrawaddy地块组成的南基墨里微地块群,漂移速度相对较慢,在空谷(Kungurian)晚期才开始出现大规模碳酸盐岩沉积,并延续至乐平世(Lopingian,晚二叠世),瓜德鲁普世和乐平世地层中含暖水生物为主的动物群,因此,这些地块至少在空谷晚期已经从冈瓦纳大陆北缘分离,裂解时间稍晚于北基墨里微地块群;这种沉积和古生物地理的时空演变差异性表明乌拉尔世的裂解事件造成了中特提斯洋和新特提斯洋的开启和形成.更北的北羌塘地块由于整个二叠纪地层中均含有典型的暖水生物群,与华南地区、思茅地块和印支地块等可以比较,属于古特提斯洋北部的块体.因此,二叠纪中、晚期特提斯域形成了古、中、新特提斯多岛洋共存的局面,是当时构造活动最活跃的地区和全球生物多样性的中心.此外,青藏高原多个块体在二叠纪位于南半球中高纬度地区,完整记录了晚古生代大冰期、亚丁斯克期全球变暖和二叠纪末快速变暖等重大古气候事件,对于阐明板块运动和全球气候演变对生物群时空分布的影响具有举足轻重的作用.

关键词：二叠纪特提斯洋青藏高原生物群古地理

IN SITU OBSERVATION OF gROWTH BEHAVIOR AND MORPHOLOgY OF DELTA-FERRITE AS FUNcTION OF SOLIDIFIcATION RATE IN AN AISI304 STAINLESS STEEL

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Acta Metallurgica Sinica(English Letters) 2006年第6期19卷 441-448页

作者： g.F.Liang c.q.Wan J.c.Wu g.M.Zhu Y.Yu Y.Fang Advanced Technology Institute Technology Center of BaosteelShanghai 201900China Department of Materials Science and Engineering Shanghai Jiao Tong UniversityShanghai 200030China

It was presented the in situ observation of growth behavior and morphology of delta-ferrite as a function of solidification rate in an AISI304 stainless steel. The specimens have been solidified and observed using confocal scanning laser microscopy (cSLM). The δ-phase always appears like cells on the sample surface when critical supercooling occurs, during which the L→δ transformation starts. The solid-liquid (S-L) interface is found to be finger shaped and has no faceted shape. γ phase appears among δ grains due to partitioning of Ni into the melt during solidification, when solidification rate is higher. The mergence of observed δ cells is possible for the steel sample cooled at 7.5℃/min. The formation of dendrites can be observed on the free surface of the steel sample cooled at 150℃/min. The size of solidified delta grains decreases from 120 to 20-80μm, and the volume fraction of solidified austenite increases with increase in solidification rate from 7.5 to 150℃/min. The relation between the tip radius of δ cell and its growth rate is deduced, and the results agree with the experimental values.

关键词： stainless steel confocal scanning laser microscopy δ-ferrite in situ observation solidification

Instrumented borehole drilling for interface identification in intricate weathered granite ground engineering

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Journal of University of Science and Technology Beijing 2007年第3期14卷 195-199页

作者： Zhuoying Tan Meifeng cai Z.q. Yue L.g Tham c.F. Lee State Key Laboratory for High-Efficient Mining and Safety of Metal Mines （University of Science and Technology Beijing） Ministry of Education Beijing 100083. China civil and Environmental Engineering School University of Science and Technology Beijing Beijing 100083 China Department of civil Engineering The University of Hong Kong Hong Kong China

The successful application in drilling for HK simple weathered granite foundation has revealed its further use in instru- mented drilling system as a ground investigation tool in the detection of other lithology formations, geohazards, underground water, and boundary of orebody. To expand the further use and test the accuracy in identification of formation, an R-20 rotary-hydraulic drill rig was instrumented with a digital drilling process monitoring system （DPM） for drilling in an intricate decomposed granite site. In this test ground, the boreholes revealed that the weathered granite alternately changes between moderate and strong. The qualitative and quantitative analysis of the penetrating parameters, indicates the effective thrust force, rotary speed, flushing pressure, penetrating rate, and displacement of the bit fluctuate at ground interfaces. It shows that the parameters get a good response with the change of rock strength at the interfaces, which can reveal the change of the intricate granite formation. Besides, a variable-slope method has been established, for identification of dominative and subsidiary interfaces in the granite site. The result from a t-test shows that the confi- dence of the instrumented drilling system in identification of the geotechnical interfaces is up to 99%.

关键词： drilling process monitoring rotary-hydraulic drilling intricate weathered granite foundation

MODIFIcATION OF SURFAcE MEcHANIcAL PROPERTIES OF POLYcARBONATE BY B^+ AND O^+ IONS IMPLANTATION

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Acta Metallurgica Sinica(English Letters) 2002年第1期15卷 33-38页

作者： S.D. Yao c. Sun S.q. Zhou c.c. Sun Y.H. Lu L. Huang A. Vantomme q. Zhao g. Langouche School of Physics Peking University Beijing 100871 China college of chemistry and Molecular Enginearing Peking University Beijing 100871 China Instituut Voor Kern-en Stralingsfysika University of Leuven B-3001 Leuven Belgium

By implanting B+ and O+ ions respectively into polycarbonate (Pc) plates, the surface mechanical properties of Pc have been improved. Measurement by Nano Indenter II showed that the hardness of samples increased 7-25 times than that before implantation; and the modulus of elasticity raised 2-5 times. The wear-resistance was tested by ball crusher; the width and depth of the wear-streak decreased by 1/3-1/2 or even more. The structure, deformation and appearance were analyzed by using Micro-FTIR Spectra, EScA method and the steps instrument. These analyses showed that the structure of Pc had been modified: a series of new cross-linking yielded, it depends on the Linear Energy Transition (LET) of implanted ions in the high polymer compounds.

关键词： polycarbonate ion implantation surface modification

Allelopathic effect of Acorus tatarinowii upon algae

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Journal of Environmental Sciences 2001年第4期13卷 481-484页

作者： He, c.-q. Wang, c.-k. Dept. of Environmental Science/Eng. Shanghai University Shanghai 200072 China

Besides competing with algae for light and mineral nutrients (i. e. N, P, etc.), the root system of Acorus tatarinowii excretes some chemical substances, which injure and eliminate alga cells, to inhibit the growth of the algae. When the algae cells were treated in 'A. tatarinowii water', some of the chlorophyll a were destroyed and the photosynthetic rate of algae decreased markedly and the ability of alga cells to deoxidize triphenyltetrazolium chloride (TTc) reduced greatly. Then alga cells turned from bright red to bluish green under fluorescence microscope. These showed that the allelopathic effects of A. tatarinowii on algae were obvious and planting A. tatarinowii can control some green algae. The experiment on the extractions of the secretions of the root system showed that the inhibitory effect had a concentration effect. If the concentration of the root secretion was below 30 μl/disc, the inhibitory rate was negative; if it was over 45 μl/disc, the inhibitory rate was positive. This proved that the influence of the root secretion on the same acceptor was a kind of concentration effect. When the concentration of the root secretion was low, it promoted the growth of algae; when the concentration reached a definite threshold value, it restrained the growth of algae. In present case, the threshold value was between 30 μl/disc and 45 μl/disc.

关键词： Algae cells chlorophyll concentration (process) Deoxidants Photosynthesis

支架特异性脂肪衰减指数与PcI术后靶血管血运重建相关

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国际医学放射学杂志 2024年第2期 251-252页

作者： F.Xu c.c.Wang q.Tao J.Zhang M.M.Zhao S.W.Shi 潘红利

摘要目的探讨支架特异性血管周围脂肪衰减指数（FAI）在支架植入病人中的临床相关性。方法回顾性纳入162例在支架植入后接受连续冠状动脉cT血管成像

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Embedding laser-generated cdTe nanocrystals into ultrathin ZnIn_(2)S_(4) nanosheets with sulfur vacancies for boosted photocatalytic H_(2) evolution

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Journal of Materials Science & Technology 2023年第35期166卷 113-122页

作者： Z.g.Tai g.T.Sun X.H.Zhang X.B.Yang T.Wang Z.Y.Fang q.Ye L.c.Jia H.q.Wang State Key Laboratory of Solidification Processing Center for Nano Energy MaterialsSchool of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072China Research&Development Institute of Northwestern Polytechnical University in Shenzhen Shenzhen 518063China School of Materials Science and Engineering Shaanxi Normal UniversityXi’an 710119China

To suppress the inner charge recombination and inject vast electrons,cdTe nanocrystals are embedded into ultrathin ZnIn_(2)S_(4) nanosheets to construct ZnIn_(2)S_(4)/cdTe heterostructures,where the nanocrystals are generated by a laser irradiation *** optimal ZnIn_(2)S_(4)/cdTe heterojunction exhibits an excellent catalytic activity of 24.3 mmol/h/g,which is relatively high among the ZnIn_(2)S_(4)-based photocatalysts with-out noble *** enhancement is ascribed to a win-win mechanism of nanoscale heterojunctions and sulfur *** strong electron coupling effect,which is verified by density functional the-ory(DFT)calculations,impels the photo-generated electrons transfer from cdTe to ZnIn_(2)S_(4),boosting the charge ***,the sulfur vacancies existing in ZnIn_(2)S_(4) can capture photoelectrons and act as active sites,facilitating the H_(2) generation *** addition,the ZnIn_(2)S_(4) base and the ZnIn_(2)S_(4)/cdTe heterojunction also possess an evident photothermal effect and renewable cycle phenomena,enhancing the photocatalytic *** research provides new insights into the regulation of charge transfer through embedding nanocrystals.

关键词： Photocatalysis Hydrogen evolution Laser irradiation Heterostructure Sulfur vacancies

EFFEcT OF HEAT TREATMENTS ON THE MIcROSTRUcTURE AND TRANSFORMATION cHARAcTERISTIcS OF TiNiPd SHAPE MEMORY ALLOY THIN FILMS

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Acta Metallurgica Sinica(English Letters) 2005年第6期18卷 707-713页

作者： c.c. Zhang c.S. Yang g.F. Ding S. q. qian J.S. Wu National Key Laboratory of Nano/Micro Fabrication Technology Key Laboratory for Thin Film and Microfabrication of Ministry of Education Institute of Micro and Nano Science and Technology Shanghai Jiaotong University Shanghai 200030 China School of Material Science and Engineering Shanghai Jiaotong University Shanghai 200030 China

Microstructure and phase transformation behaviors of the film annealed at different temperatures were studied by X-ray diffractometry （XRD）, transmission electron microscopy and differential scanning calorimeter （DSc）. Also tensile tests were examined. For increasing annealed temperature, multiple phase transformations, transformations via a B19-phase or direct martensite/austenite transformtion are observed. The TiNiPd thin film annealed at 750℃ had relatively uniform martensite/austenite transformtion and shape memory effect. Martensite/austenite transformtion was also found in strain-temperature curves. Subsequent annealing at 450℃ had minor effect on transformation temperatures of Ti-Ni-Pd thin films but resulted in more uniform transformation and improved shape memory effect.

关键词： Ti-Ni-Pd thin films microstructure martensitic phase transformation,shape memory effect

Determination of the number ofψ(3686)events taken at BESⅢ

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chinese Physics c 2024年第9期48卷 8-20页

作者： M.Ablikim M.N.Achasov P.Adlarson O.Afedulidis X.c.Ai R.Aliberti A.Amoroso q.An Y.Bai O.Bakina I.Balossino Y.Ban H.-R.Bao V.Batozskaya K.Begzsuren N.Berger M.Berlowski M.Bertani D.Bettoni F.Bianchi E.Bianco A.Bortone I.Boyko R.A.Briere A.Brueggemann H.cai X.cai A.calcaterra g.F.cao N.cao S.A.cetin J.F.chang g.R.che g.chelkov c.chen c.H.chen chao chen g.chen H.S.chen H.Y.chen M.L.chen S.J.chen S.L.chen S.M.chen T.chen X.R.chen X.T.chen Y.B.chen Y.q.chen Z.J.chen Z.Y.chen S.K.choi g.cibinetto F.cossio J.J.cui H.L.Dai J.P.Dai A.Dbeyssi R.E.de Boer D.Dedovich c.q.Deng Z.Y.Deng A.Denig I.Denysenko M.Destefanis F.De Mori B.Ding X.X.Ding Y.Ding Y.Ding J.Dong L.Y.Dong M.Y.Dong X.Dong M.c.Du S.X.Du Y.Y.Duan Z.H.Duan P.Egorov Y.H.Fan J.Fang J.Fang S.S.Fang W.X.Fang Y.Fang Y.q.Fang R.Farinelli L.Fava F.Feldbauer g.Felici c.q.Feng J.H.Feng Y.T.Feng M.Fritsch c.D.Fu J.L.Fu Y.W.Fu H.gao X.B.gao Y.N.gao Yang gao S.garbolino I.garzia L.ge P.T.ge Z.W.ge c.geng E.M.gersabeck A.gilman K.goetzen L.gong W.X.gong W.gradl S.gramigna M.greco M.H.gu Y.T.gu c.Y.guan Z.L.guan A.q.guo L.B.guo M.J.guo R.P.guo Y.P.guo A.guskov J.gutierrez K.L.Han T.T.Han F.Hanisch X.q.Hao F.A.Harris K.K.He K.L.He F.H.Heinsius c.H.Heinz Y.K.Heng c.Herold T.Holtmann P.c.Hong g.Y.Hou X.T.Hou Y.R.Hou Z.L.Hou B.Y.Hu H.M.Hu J.F.Hu S.L.Hu T.Hu Y.Hu g.S.Huang K.X.Huang L.q.Huang X.T.Huang Y.P.Huang T.Hussain F.Hölzken N.Hüsken N.in der Wiesche J.Jackson S.Janchiv J.H.Jeong q.Ji q.P.Ji W.Ji X.B.Ji X.L.Ji Y.Y.Ji X.q.Jia Z.K.Jia D.Jiang H.B.Jiang P.c.Jiang S.S.Jiang T.J.Jiang X.S.Jiang Y.Jiang J.B.Jiao J.K.Jiao Z.Jiao S.Jin Y.Jin M.q.Jing X.M.Jing T.Johansson S.Kabana N.Kalantar-Nayestanaki X.L.Kang X.S.Kang M.Kavatsyuk B.c.Ke V.Khachatryan A.Khoukaz R.Kiuchi O.B.Kolcu B.Kopf M.Kuessner X.Kui N.Kumar A.Kupsc W.Kühn J.J.Lane P.Larin L.Lavezzi T.T.Lei Z.H.Lei M.Lellmann T.Lenz c.Li c.Li c.H.Li cheng Li D.M.Li F.Li g.Li H.B.Li H.J.Li H.N.Li Hui Li J.R.Li J.S.Li Ke Li L.J.Li L.K.Li Lei Li M.H.Li P.R.Li q.M.Li q.X.Li R.Li S.X.Li T.Li W.D.Li W.g.Li X.Li X.H.Li X.L.Li X.Z.Li Xi Institute of High Energy Physics Beijing 100049China Beihang University Beijing 100191China Bochum Ruhr-University D-44780BochumGermany Budker Institute of Nuclear Physics SB RAS(BINP) Novosibirsk 630090Russia carnegie Mellon University PittsburghPennsylvania 15213USA central china Normal University Wuhan 430079China central South University Changsha 410083China china center of Advanced Science and Technology Beijing 100190China china University of geosciences Wuhan 430074China chung-Ang University Seoul06974Republic of Korea cOMSATS University Islamabad Lahore CampusDefence RoadOff Raiwind Road54000LahorePakistan Fudan University Shanghai 200433China gSI Helmholtzcentre for Heavy Ion Research gmbH D-64291DarmstadtGermany guangxi Normal University Guilin 541004China guangxi University Nanning 530004China Hangzhou Normal University Hangzhou 310036China Hebei University Baoding 071002China Helmholtz Institute Mainz Staudinger Weg 18D-55099MainzGermany Henan Normal University Xinxiang 453007China Henan University Kaifeng 475004China Henan University of Science and Technology Luoyang 471003China Henan University of Technology Zhengzhou 450001China Huangshan college Huangshan 245000China Hunan Normal University Changsha 410081China Hunan University Changsha 410082China Indian Institute of Technology Madras Chennai 600036India Indiana University BloomingtonIndiana 47405USA INFN Laboratori Nazionali di Frascati (A)INFN Laboratori Nazionali di FrascatiI-00044FrascatiItaly(B)INFN Sezione di PerugiaI-06100PerugiaItaly(C)University of PerugiaI-06100PerugiaItaly INFN Sezione di Ferrara (A)INFN Sezione di FerraraI-44122FerraraItaly(B)University of FerraraI-44122FerraraItaly Inner Mongolia University Hohhot 010021China Institute of Modern Physics Lanzhou 730000China Institute of Physics and Technology Peace Avenue 54BUlaanbaatar 13330Mongolia Instituto de Alta Investigación Universidad de TarapacáCasilla 7DArica 1000000Chile Jilin University Changchun 130012China Joha

The number ofψ(3686)events collected by the BESⅢdetector during the 2021 run period is determined to be(2259.3±11.1)×10~6 by counting inclusiveψ(3686)hadronic *** uncertainty is systematic and the statistical uncertainty is ***,the numbers ofψ(3686)events collected during the 2009 and 2012run periods are updated to be(107.7±0.6)×10~6 and(345.4±2.6)×10~6,*** numbers are consistent with the previous measurements within one standard *** total number ofψ(3686)events in the three data samples is(2712.4±14.3)×10~6.

关键词： ψ(3686) inclusive process Hadronic events BESⅢdetector