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STUDY OF THE MIcROSTRUcTURE SIMULATION AND PERFORMANcE OF FUSION WELDING HAZ OF ZINc-BASED ALLOY

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Acta Metallurgica Sinica(English Letters) 2000年第1期13卷 173-177页

作者： k.k. Zhang D.R. chen J. Xue D. W. Sun and H.c. Li( 1) Department of Materials Engineer, Xi’an Jiaotong University, Xi’an 710049, china 2) Luoyang Institute of Technology, Luoyang 471039, china 3) cITIc Heavy)

Base on a vast amount of testing and calculations for the welding thermal cycling curves of different testing points in fusion welding (TIG welding, gas welding) HAZ of zinc-based alloy with low melting points, this paper defines the welding thermal cycle parameters of microstructure stimulation of HAZ by zinc-based alloy fusion welding process. On the principle of which the microstrnct,are and harkness of the testing points in simulation specimens are basically correspondence with that of actual welding HAZ, the microstructure simulation of testing points Tm=370O℃. 305℃) of ZA12 alloy by fusion welding is carried out by the means of omhic-heating welding thermal simulation tester. The study results of the abrasion-resistance of simulation specimens HAZ by fusion welding process indicates that the abmsion-resistance is closely related to the form of eutectoid microstructure in or in the structure.

关键词： zinc-based alloy HAZ microstructure thermal simulation abrasion-resistance

Numerical modelling of a low power non-transferred arc plasma reactor for methane conversion

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Plasma Science and Technology 2019年第6期21卷 29-37页

作者： B I MIN D k DINH D H LEE T H kIM S cHOI Institute for Nuclear Science and Technology Jeju National University 102 Jejudaehak-ro Jeju 63243Republic of Korea University of Science and Technology(UST) 217 Gajeong-ro Yuseong-gu Daejeon 34113 Republic of Korea korea Institute of Machinery and Materials 156 Gajeongbuk-ro Yuseong-gu Daejeon 34103 Republic of Korea Department of Nuclear and Energy Engineering Jeju National University 102 Jejudaehak-ro Jeju 63243Republic of Korea

Thermal flow characteristics and the methane conversion reaction in a low power arc plasma reactor for efficient storage and transport of methane,which is the main component of shale gas,were *** temperature and velocity distributions were calculated according to the type of discharge gases and arc current level by a self-developed magnetohydrodynamics (MHD)code and a commercial ANSYS-FLUENT code;the transport of chemical species was analyzed as including the chemical reactions of methane *** simulated results were verified by the comparison of calculated and measured arc voltages with permissible low error as under 4%.Three c2 hydrocarbon gases with ethane (c2H6),ethylene (c2H4),and acetylene (c2H2)were selected as the converted species of methane from experimental *** mass fraction of c2 hydrocarbons and hydrogen as the product of the conversion reaction at the reactor was also *** values show good agreement with the actual experimental results in that the major conversion reaction occurred in c2H2 and hydrogen,and the conversions to c2H6,c2H4,and hydrogen were minor reactions of methane pyrolysis conversion.

关键词： numerical modelling non-transferred arc plasma methane chemical reaction

Origin of Red color of the Lower Siwalik Palaeosols:A Micromorphological Approach

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Journal of Mountain Science 2009年第2期6卷 147-154页

作者： Seema Singh B.Parkash Arun.k.Awasthi Department of Earth Sciences Indian Institute of Technology RoorkeeRoorkee-247667 India Department of Earth Sciences Indian Institute of Technology RoorkeeRoorkee–247667 India

Palaeosols associated with fluvial of the Siwalik Group are and lacustrine deposits that occur as thick multiple pedocomplexes. The bright red color of the palaeosol beds has been earlier interpreted as a result of hot and arid palaeoclimate. However, as against this view, our investigations of the bright red palaeosol beds of the Lower Siwaliks suggest that the climate was cool and subhumid, instead of hot and arid during the deposition of these beds. Since cold climate is not very conducive to impart red coloration, further research is needed to explain the cause of these red beds. For this, the micromorphological study of soil thin sections was done which showed the presence of features such as dissolution and recrystallisation of quartz, feldspar and mica, compaction, slickensides, presence of calcite spars, subrounded and cracked nature of quartz grains, microfabric, complex patterns of birefringence fabrics, pigmentary ferric oxides, thick cutans and cementation by calcite. These features indicate that diagenesis took place on a large scale in these sediments. The positive Eh and neutral-alkaline pH of soils also suggest that the conditions were favorable for the formation of diagenetic red beds. During burial diagenesis of sediments, the hydroxides of ferromagnesian minerals got converted into ferric oxide minerals （hematite）. During deep burial diagenesis smectite was converted into illite and the preponderance of illite over smectite with increasing depth of burial also indicates the diagenesis of sediments. Thus, the red color of the Lower Siwalik palaeosols seems to be due mainly to the burial diagenesis of sediments and does not appear to be due to the then prevailing climatic condition.

关键词： Palaeosols c3 type vegetation diagenetic red beds calcite spars

Online AUV Path Replanning Using Quantum-Behaved Particle Swarm Optimization with Selective Differential Evolution

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computer Modeling in Engineering & Sciences 2020年第10期125卷 33-50页

作者： Hui Sheng Lim christopher k.H.chin Shuhong chai Neil Bose National centre for Maritime Engineering and Hydrodynamics Australian Maritime CollegeUniversity of TasmaniaLauncestonTAS7250Australia Memorial University of Newfoundland St.John’sNLA1C 5S7Canada

This paper presents an online AUV(autonomous underwater vehicle)path planner that employs path replanning approach and the SDEQPSO(selective differential evolution-hybridized quantum-behaved particle swarm optimization)algorithm to optimize an AUV mission conducted in an unknown,dynamic and cluttered ocean *** proposed path replanner considered the effect of ocean currents in path optimization to generate a Pareto-optimal path that guides the AUV to its target within minimum *** optimization was based on the onboard sensor data measured from the environment,which consists of a priori unknown dynamic obstacles and spatiotemporal *** sensor arrangements for the forward-looking sonar and horizontal acoustic Doppler current profiler(H-ADcP)were considered in 2D and 3D *** on the simulation results,the SDEQPSO path replanner was found to be capable of generating a time-optimal path that offered up to 13%reduction in travel time compared to the situation where the vehicle simply followed a path with the shortest *** proposed replanning technique also showed consistently better performance over a reactive path planner in terms of solution quality,stability,and computational *** of the replanner was verified under stochastic process using the Monte carlo *** generated path fulfilled the vehicle’s safety and physical constraints,while intelligently exploiting ocean currents to improve the vehicle’s efficiency.

关键词： Autonomous underwater vehicle path planning particle swarm optimization sonar detection Monte carlo methods

Phylogeny of the Insect Homeobox Gene (Hox) cluster

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Genomics, Proteomics & Bioinformatics 2005年第1期3卷 42-46页

作者： Sangeeta Dhawan k. P. Gopinathan Department of Microbiology and cell Biology Indian Institute of Science Bangalore 560012 India. Department of Microbiology and Cell Biology Indian Institute of Science Bangalore 560012 India.

The homeobox （Hox） genes form an evolutionarily conserved family encoding transcription factors that play major roles in segmental identity and organ specification across species. The canonical grouping of Hox genes present in the HOM-c cluster of Drosophila or related clusters in other organisms includes eight “typical” genes, which are localized in the order labial （lab）, proboscipedia （pb ）, Deformed （ Dfd）, Sex combs reduced （Scr）, Antennapedia （Antp）, Ultrabithorux （Ubx）, abdominalA （abdA）, and AbdominalB （AbdB）. The members of Hox cluster are expressed in a distinct anterior to posterior order in the embryo. Analysis of the relatedness of different members of the Hox gene cluster to each other in four evolutionarily diverse insect taxa revealed that the loci pb/Dfd and AbdB, which are farthest apart in linkage, had a high degree of evolutionary relatedness, indicating that pb/Dfd type anterior genes and AbdB are closest to the ancestral anterior and posterior Hox genes, respectively. The greater relatedness of other posterior genes Ubx and abdA to the more anterior genes such as Antp and Scr suggested that they arose by gene duplications in the more anterior members rather than the posterior AbdB.

关键词： evolution homeodomain Hox genes insects phylogeny

The interrelationship between cerebral ischemic stroke and glioma: a comprehensive study of recent reports

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Signal Transduction and Targeted Therapy 2019年第1期4卷 298-310页

作者： Mrinal k.Ghosh Dipankar chakraborty Sibani Sarkar Arijit Bhowmik Malini Basu Signal Transduction in cancer and Stem cells Laboratory Division of Cancer Biology and Inflammatory DisorderCouncil of Scientific and Industrial Research-Indian Institute of Chemical Biology(CSIR-IICB)4 Raja S.C.Mullick RoadKolkata 700032 and CN-06Sector-VSalt LakeKolkata 700091India Department of cancer chemoprevention Chittaranjan National Cancer Institute37 S.P.Mukherjee RoadKolkata 700026India Department of Microbiology Dhruba Chand Halder CollegeDakshin BarasatSouth 24Paraganas 743372India

Glioma and cerebral ischemic stroke are two major events that lead to patient death *** these conditions have different physiological incidences,~10%of ischemic stroke patients develop cerebral cancer,especially glioma,in the postischemic ***,the high proliferation,venous thrombosis and hypercoagulability of the glioma mass increase the significant risk of thromboembolism,including ischemic ***,these events share several common pathways,***,cerebral inflammation,angiogenesis,etc.,but the proper mechanism behind this co-occurrence has yet to be *** hypercoagulability and presence of the D-dimer level in stroke are different in cancer patients than in the noncancerous *** factors such as atherosclerosis and coagulopathy involved in the pathogenesis of stroke are partially responsible for cancer,and the reverse is also partially *** on clinical and neurosurgical experience,the neuronal structures and functions in the brain and spine are observed to change after a progressive attack of ischemia that leads to hypoxia and *** major population of cancer cells cannot survive in an adverse ischemic environment that excludes cancer stem cells(cScs).cancer cells in stroke patients have already metastasized,but early-stage cancer patients also suffer stroke for multiple ***,stroke is an early manifestation of *** and cancer share many factors that result in an increased risk of stroke in cancer patients,and *** intricate mechanisms for stroke with and without cancer are *** review summarizes the current clinical reports,pathophysiology,probable causes of co-occurrence,prognoses,and treatment possibilities.

关键词： cerebral glioma sized

一种用于从水中分离挥发性有机化合物的疏水性渗透汽化中空纤维复合膜(英文)

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膜科学与技术 2003年第4期23卷 7-15页

作者： Garba O.Yahya Fakhir U.Baig Majid kazi c.k.Yeom Petro Sep Membranes Research Inc. 2270 Speers Road Petro Sep Membranes Research Inc. 2270 Speers RoadPetro Sep Membranes Research Inc. 2270 Speers RoadPetro Sep Membranes Research Inc. 2270 Speers Road Oakville Ontario L6L 2X8 CanadaOakville Ontario L6L 2X8CanadaOakville Ontario L6L 2X8 CanadaOakvilleOntario L6L 2X8 Canada

研制出一种名为VOc -SEP2 0 0新型中空纤维疏水性复合膜 ,并考察了这种复合膜从水中分离BTEX(苯、甲苯、乙苯和二甲苯 )的性能 .这 4种芳香碳氢化合物是工业有机废水中的一组有代表性的污染物 ,本研究的最终目的是想从现实的工业废水中... 详细信息

研制出一种名为VOc -SEP2 0 0新型中空纤维疏水性复合膜 ,并考察了这种复合膜从水中分离BTEX(苯、甲苯、乙苯和二甲苯 )的性能 .这 4种芳香碳氢化合物是工业有机废水中的一组有代表性的污染物 ,本研究的最终目的是想从现实的工业废水中回收这些化合物 .采用料液在纤维中孔流动的方式 ,系统考察了进料液流速、操作压力、温度和进料液浓度对膜分离效率及膜性能的影响 .结果显示 ,随着进料液流速的提高 ,BTEX的通量随之增大 .这是由于随着进料液流速的提高 ,浓度极化的影响会减少 ,同时BTEX和水的分离因子会有显著增大 .结果还显示 ,膜的性能随膜横向的驱动力降低而提高 ,其最佳的渗透压范围是 10 .7～ 13.3kPa(即 80～ 10 0mmHg) ,此时BTEX通量达到最大平稳值 ,同时水的通量最小 .提高渗透压可减少操作费用 ,同时可增强分离效果 .和预期的情况一样 ,BTEX和水的渗透通量都随着温度和进料浓度的提高而增大 ,但再进一步提高浓度和温度 ,则对水通量不产生影响 .水通量在初始阶段的增加可以归因于膜的溶胀 ,水通量不再随温度和浓度的进一步升高而增加 ,可以归因于水分子的聚集与膜的溶胀达到了平衡 .

关键词：水分离挥发性有机化合物疏水性渗透汽化中空纤维复合膜

乌干达金贾医院以皮肤病就诊发现人免疫缺陷病毒感染35例临床分析

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实用皮肤病学杂志 2013年第2期6卷 91-92页

作者：肖云 NGOBI HENRY MANSON rose NABIRYE 昆明市中医医院皮肤科 650011 乌干达金贾医院艾滋病科乌干达金贾医院儿科

从人免疫缺陷病毒（HIV）感染发展到艾滋病（AIDS），未经治疗潜伏期一般为1～10年，艾滋病前期感染者会出现各种各样的皮肤病变[1]。笔者于2007年8月～2009年8月在非洲乌干达金贾医院工作期间诊治了许多皮肤病患者，其中35例（非洲黑... 详细信息

从人免疫缺陷病毒（HIV）感染发展到艾滋病（AIDS），未经治疗潜伏期一般为1～10年，艾滋病前期感染者会出现各种各样的皮肤病变[1]。笔者于2007年8月～2009年8月在非洲乌干达金贾医院工作期间诊治了许多皮肤病患者，其中35例（非洲黑种人）初查HIV阳性。现将35例患者的临床资料进行回顾性分析。

关键词：皮肤病感染人免疫缺陷病毒临床分析

Absolute Generalized Oscillator Strength Profile of Negative Ion Resonance at 8.9 eV in c2F6

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chinese Physics Letters 2005年第3期22卷 591-594页

作者：樊晓伟耿振铎张岩松 k.T.Leung DepartmentofPhysics HenanNormalUniversityXinxiang453007 DepartmentofPhysics HenanNormalUniversityXinxiang453007//DepartmentofChemistryUniversityofWaterlooWaterlooOntarioN2L3G1Canada Departmentofchemistry UniversityofWaterlooWaterlooOntarioN2L3G1Canada

A temporary negative ion resonance at 8.9eV in c2F6 has been clearly identified using angle-resolved electron energy loss spectroscopy at 2.5keV impact energy, and can be attributed to electron capture into 12a1u, 12a1g, 22a2u, and 12eg virtual molecular orbitals. The corresponding absolute generalized oscillator strength profile is found to have a shape characteristic of non-dipole interaction with the maximum k~0.8a.u. of momentum transfer.

关键词： Absolute Generalized Oscillator Strength Profile Negative Ion Resonance