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The present research brings new insights on the role of admixed corrosion inhibitors in the processes of cement hydration and rebar corrosion.The admixing of NaCl and the corrosion inhibitors in fresh mortar was found to alter the morphology and microstructure of the hardened mortar at the steel-mortar interfacial region.The admixing of the inhibitors increased the risk of carbonation of cement hydrates at the steel-mortar interfacial region,but partially displaced chloride ions. Chloride and the admixed in... 相似文献
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Donald C. Maclurcan 《科学观察》2006,1(5):1-09
作者将“nano*”与世界银行确定的每个经济类主题词组合检索,结果发现发展中国家普遍在从事
纳米技术研发。进一步研究表明,尽管发展中国家纳米技术的研发能力随着合作和信息利用的加强而提高,
但是这些国家已经偏离了纳米技术的“社会开发”这一通常被认为是最适于发展中国家的研究宗旨。另外,
对卫生保健相关专利的分析证实,各国实力严重不平衡,存在所谓的“纳米鸿沟”现象。在发展中国家中,
中国拥有的专利权所占份额很高,因此“纳米鸿沟”不仅存在于发展中国家和发达国家之间,在发展中国
家也同样存在。发展中国家的研发水平较低,纳米技术有可能走向以往导致全球技术大分裂的技术老路。 相似文献
纳米技术研发。进一步研究表明,尽管发展中国家纳米技术的研发能力随着合作和信息利用的加强而提高,
但是这些国家已经偏离了纳米技术的“社会开发”这一通常被认为是最适于发展中国家的研究宗旨。另外,
对卫生保健相关专利的分析证实,各国实力严重不平衡,存在所谓的“纳米鸿沟”现象。在发展中国家中,
中国拥有的专利权所占份额很高,因此“纳米鸿沟”不仅存在于发展中国家和发达国家之间,在发展中国
家也同样存在。发展中国家的研发水平较低,纳米技术有可能走向以往导致全球技术大分裂的技术老路。 相似文献
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A novel order reduction method for nonlinear dynamical system under external periodic excitations 下载免费PDF全文
CAO DengQing WANG JinLin & HUANG WenHu School of Astronautics Harbin Institute of Technology PO Box Harbin China 《中国科学:技术科学》2010,(2)
The concept of approximate inertial manifold (AIM) is extended to develop a kind of nonlinear order reduction technique for non-autonomous nonlinear systems in second-order form in this paper. Using the modal transformation, a large nonlinear dynamical system is split into a ‘master’ subsystem, a ‘slave’ subsystem, and a ‘negligible’ subsystem. Accordingly, a novel order reduction method (Method I) is developed to construct a low order subsystem by neglecting the ‘negligible’ subsystem and slaving the ‘slav... 相似文献
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Andrés E Askebjer P Bai X Barouch G Barwick SW Bay RC Becker KH Bergström L Bertrand D Bierenbaum D Biron A Booth J Botner O Bouchta A Boyce MM Carius S Chen A Chirkin D Conrad J Cooley J Costa CG Cowen DF Dailing J Dalberg E DeYoung T Desiati P Dewulf JP Doksus P Edsjö J Ekström P Erlandsson B Feser T Gaug M Goldschmidt A Goobar A Gray L Haase H Hallgren A Halzen F Hanson K Hardtke R He YD Hellwig M Heukenkamp H Hill GC Hulth PO Hundertmark S Jacobsen J Kandhadai V Karle A Kim J Koci B Köpke L 《Nature》2001,410(6827):441-443
Neutrinos are elementary particles that carry no electric charge and have little mass. As they interact only weakly with other particles, they can penetrate enormous amounts of matter, and therefore have the potential to directly convey astrophysical information from the edge of the Universe and from deep inside the most cataclysmic high-energy regions. The neutrino's great penetrating power, however, also makes this particle difficult to detect. Underground detectors have observed low-energy neutrinos from the Sun and a nearby supernova, as well as neutrinos generated in the Earth's atmosphere. But the very low fluxes of high-energy neutrinos from cosmic sources can be observed only by much larger, expandable detectors in, for example, deep water or ice. Here we report the detection of upwardly propagating atmospheric neutrinos by the ice-based Antarctic muon and neutrino detector array (AMANDA). These results establish a technology with which to build a kilometre-scale neutrino observatory necessary for astrophysical observations. 相似文献
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Summary Aspiration of the one femoral bone marrow caused a significant rise of the cell population, arrested in colchicine-metaphase both of the bone marrow from the other femur and of the thymus. 相似文献
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