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Morphological dependence of passive epitaxial oxide films on nanoparticles of iron

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电子显微学报 2002年第5期21卷 601-602页

作者： FUNGKwokKwong ZHANGXi0xiang DepartmentofPhysics TheHongKongUniversityofScienceandTechnologyClearWaterBayKowloonHongKongSARCHina DepartmentofPhysics TheHongKongUniversityofScienceandTechnologyClearWaterBayKowloonHongKongSA

Nanoparticles of iron passivated by thin oxide films are {110} rhombic dodecahedra truncated by {100} planes with various degree of truncation. The degree of truncation is defined as the ratio of the edge length of the truncated part to the full edge length of the rhombic dodecahedron. Uyeda and coworkers have shown that nanoparticles with low degree of truncation are bounded by six small {100} and twelve large {110} facets while nanoparticles with high degree of truncation are bounded by large {100} and small {110} facets.

关键词：电子显微镜组织形貌晶体生长氧化物薄膜铁耐蚀防护

MOBILITY EVALUATION AND INNOVATION OF WHEELED SPACE ROVER

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Chinese Journal of Mechanical Engineering 2006年第2期19卷 187-190页

作者： SHANG Jianzhong LU0 Zirong LI Shengyi TANG Li School of Mechanical Science and Engineering Huazhong University of Science and TechnologyWuhan 430074 China School of Mechatronics Engineering and Automation National University of Defense TechnologyChangsha 410073 China

The mission and function requirements of lunar rover are analyzed, based on virtual prototype technology, the mobility evaluation theory and method for wheeled space rover are proposed, which provide a new way to study the innovative design of lunar rover. Based on the above theoretical system, an innovative lunar rover suspension system, which adopts a two-crank-slider mechanism, is proposed, and its dynamics model is created. Adopting virtual prototype technology, the ground adaptability, over-obstacle ability and driving placidity of the rover are evaluated in the virtual prototype software ADAMS. The analysis results show that the rover provides a high degree of mobility.

关键词： Space rover Mobility Virtual prototype Suspension

Site 0ccupancy of Alloying Elements and Their Effects on the D0_3 Phase Stability in Fe_3Al

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Journal of Materials Science & Technology 1999年第4期15卷 339-341页

作者： Jun CAF Shaojun LIU Ying LOU and Benkuan usDepartment 0f Physics, Beijing N0rmal University, Beijing lO0875, ChinaSuqing D UANInstitute of Applied Physics and Computati0nal Mathematics, Beijing 100088, China Department of Physics Beijing Normal University Beijing 100875 China Institute of Applied Physics and Computational Mathematics Beijing 100088 China

The effects of ternary solutes Ti, Co, V, Cr, Ta, W and Mo on the D03 phase 5tability of Fe3Alintermetallics are investigated by tight-binding linear Muffin-tin orbitaI method. The predictedsite preference5 of these elements in Fe3AI are in agreement with the experimental *** calculated Iocal magnetic moment of Fe3AI is identical to the experimentaI. ln addition, itis found that the D03 phase stability of Fe3AI doped with Ti, V, Co and Cr depends on 'energygap- of energy band near Fermi level. while the D03 phase stability of Fe3AI doped with Ta, Wand Mo may be affected by Madelung energy.

关键词： Al Fe Site 0ccupancy of Alloying Elements and Their Effects on the D03 Phase Stability in Fe3Al

Effects of Haloxylon spp. of Different Age Classes on Vegetation Cover and Soil Properties on an Arid Desert Steppe in Iran

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Pedosphere 2019年第5期29卷 619-631页

作者： Mahdieh EBRAHIMI Fereshteh M0HAMMADI Akbar FAKHIREH Abolfazl BAMERI Department of Range and Watershed Management University of ZabolZabol *** (Iran) Department of Range and Watershed Management University of Gonbad KavosFalahi StreetBasirat BoulevardGonbad Kavos P.O. Box 163 (Iran) Department of Soil Sciences University of ZabolZabol *** (Iran)

In arid regions,afforestation has been considered as a method for ecological revival in terms of vegetation enrichment and soil *** this study,the effects of afforestation with Haloxylon *** vegetation cover and soil properties were measured0-30 and 30-60 cm)under and between shrub *** succession significantly affected plant community *** total,16 species from 8families and 15 genera were observed along the afforestation successional *** species richness and diversity and vegetation cover increased slowly during the succession,and reached the maximum values in the area where Haloxylon had been planted for25 *** nutrient values gradually increased during the succession,and the levels of organic matter,total nitrogen,available potassium,and available phosphorus were significantly higher under Haloxylon canopies than between *** reduced soil pH under and between Haloxylon canopies during the succession,while soil electrical conductivity followed an opposite *** planting increased the silt content in the 0-30 cm soil *** results suggest that Haloxylon establishment plays an important role in the reestablishment of desertified ecosystems in arid regions.

关键词： afforestation succession arid land desertification control plant community soil amelioration species diversity species richness vegetation enrichment

Retrofitting of RC Slabs Against Explosive Loads

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Transactions of Tianjin University 2006年第B09期12卷 88-93页

作者： WU Chengqing 0EHLERS Deric John XIA Shaohua School of Civil and Environmental Engineering The University of Adelaide Australia Defence Science and Technological Organization Australia

With the increase of terrorist bomb attacks on buildings, there is a need to develop advanced retrofitting techniques to strengthen structures against blast loads. Currently, several guidelines including an Australian version for retrofitting reinforced concrete (RC) structures are available for the design of retrofitting systems against seismic and monotonic loads using steel or fibre reinforced polymer (FRP) plates that can be either adhesively bonded to the surface or near surface mounted to the concrete cover. However, none of these guidelines provide advice suitable for retrofitting structures subjected to blast loads. In this paper, numerical models are used to simulate the performance of retrofitted RC slabs subjected to blast loads. Airblast pressure distributions on the surface of the slabs estimated in a previous study are used as input in the analysis. A material damage model developed previously for concrete and an elastoplastic model for steel bars are employed in this research for modelling reinforced concrete behaviour due to explosive loads. The material models and blast loading are coded into a finite element computer program LS-DYNA3D to do the analysis. With the numerical model, parametric studies are conducted to investigate RC slabs retrofitted by either externally bonded or near-surface mounted plates or GFRP sheets subjected to blast loads. Discussion is made on the effectiveness of the retrofitting system for RC slabs against blast loads.

关键词： retrofit explosion fibre reinforced polymer slab

Development of setal patterns in embryonic and adult aphids of the Hormaphidinae （Hemiptera： Aphididae）

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Insect Science 2007年第4期14卷 339-350页

作者： LI-YUN JIANG GE-XIA QIA0 GUANG-XUE ZHANG Institute of Zoology Chinese Academy of Sciences Graduate University of Chinese Academy of Sciences BeijingChina

The elementary traits and diversity of embryonic setal patterns of 31 species of 22 genera, in three tribes of Hormaphidinae are studied. The embryonic setal patterns to every species are provided. Based on the parsimony principle and the developmental principle, these patterns are analyzed in each tribe following the terminology of Richards （1965）. It is suggested that the setal patterns of abdominal tergites are the most important characters in embryonic and adult setal patterns. In conclusion, neoteny is a phylogenetic trend in the Hormaphidinae. Nipponaphidini and Hormaphidini have more typical neoteny in each genus and more diversity in different types of adult viviparous females than Cerataphidini, by showing more frequent and various protopatterns or mesopatterns.

关键词： Hemiptera Hormaphidinae embryo adult setal pattern development neo-teny

HOT EMBOSSING METHODS FOR PLASTIC MICROCHANNEL FABRICATION

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Chinese Journal of Mechanical Engineering 2006年第2期19卷 223-225页

作者： LIU Junshan WANG Liding LIU Chong LU0 Yi Key Laboratory for Micro/Nano Technology and System of Liaoning Province Dalian University of TechnologyDalian 116023 China

Fabrication of microchannels on polymethylmethacrylate （PMMA） substrates using novel microfabrication methods is demonstrated. The image of microchannels is transferred from a silicon master possessing the inverse image of the microchannel to a PMMA plate by using hot embossing methods. The silicon master is electrostatically bonded to a Pyrex 7740 glass wafer, which improves the device yield from about 20 devices to hundreds of devices per master. Effects of embossing temperature, pressure and time on the accuracy of replication are systematically studied using the orthogonal factorial design. According to the suggested experimental model, the time for the whole embossing procedure is shorten from about 20 min to 6 min, and the accuracy of replication is 99.3%. The reproducibility of the hot embossing method is evaluated using 10 channels on different microfluidic devices, with variations of 1.4 % in depth and 1.8% in width.

关键词： Microchannel Microfluidics Hot embossing Plastic Polymethylmethacrylate (PMMA)

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催化性抗体及其研究进展

生物化学与生物物理进展 1997年第3期24卷 198-203页

作者：胡昌勤中国药品生物制品检定所北京100050

根据过渡态理论 ,按特定的化学反应机制确定反应中的可能过渡态结构 ,选择和该过渡态结构类似的化合物作为半抗原 ,可诱导机体产生具有催化活性的催化性抗体 .文章对诱导催化性抗体中半抗原的选择原则、催化性抗体和非催化性抗体间的联... 详细信息

根据过渡态理论 ,按特定的化学反应机制确定反应中的可能过渡态结构 ,选择和该过渡态结构类似的化合物作为半抗原 ,可诱导机体产生具有催化活性的催化性抗体 .文章对诱导催化性抗体中半抗原的选择原则、催化性抗体和非催化性抗体间的联系、催化性抗体和酶促催化反应的比较等方面进行了较为全面的综述。

关键词：催化性抗体抗体

Phase Transition for Dielectric Breakdown Model

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Communications in Nonlinear Science and Numerical Simulation 1997年第4期2卷 201-206页

作者： Fuxuan CHANG &Houqiang LI &De L IU &L ibin L IN (Department of Physics. Open laboratory of Radiation Physics and Technology,Sichuan University,Chengdu,6 1 0 0 6 4,China) 1The paper was received on Nov. 2 0 ,1997 Department of Physics Open laboratory of Radiation Physics and Technology Sichuan University Chengdu 610064 China

In this paper,the phase transition for DBM whenηvaries is investigated by using real- space renormalization-group method. The resultdemonstrates that there are phase transitions for almost all the value ofη,and we f... 详细信息

关键词： DBM phase transition renormalization-group