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排序方式: 共有10000条查询结果,搜索用时 281 毫秒
41.
Baranov D. A. Zhatkin S. S. Nikitin V. I. Deev V. B. Nikitin K. V. Barinov A. Yu. Yudin D. M. 《Russian Journal of Non-Ferrous Metals》2021,62(4):441-447
Russian Journal of Non-Ferrous Metals - The process of making a weld using the heat-resistant EP693 alloy (Ni–Cr–W–Co–Co–Mo system) to make assemblies and components... 相似文献
42.
Demirov A. P. Blinkov I. V. Kuznetsov D. V. Kuskov K. V. Kolesnikov E. A. Sedegov A. S. 《Russian Journal of Non-Ferrous Metals》2021,62(5):602-610
Russian Journal of Non-Ferrous Metals - This article discusses methods for producing a material with gradient multilevel porosity by sintering layer-by-layer distributed α-Fe2O3 nanopowders... 相似文献
43.
Lysunenko N.O. Brodnikovskyi Y.M. Mokiichuk V.M. Polishko I.O. Brodnikovskyi D.M. Chedryk V.I. Vasylyev O.D. 《Powder Metallurgy and Metal Ceramics》2021,60(5-6):352-359
Powder Metallurgy and Metal Ceramics - Fuel cells are today among the most efficient and environmentally friendly devices for the production of electricity. They are developing rapidly and are... 相似文献
44.
Innovation is invariably accepted as a central component of construction sector competitiveness. Yet, there remains a paucity of empirical research, which explores the gap between the way innovation is promoted in the policy discourse and how it is interpreted in practice. We follow the “narrative turn” in organization studies to explore the ways in which senior executives in the UK construction sector ascribe themselves with informal roles while advocating the cause of innovation. Empirical data is derived from narrative interviews with 32 senior executives who self-identify as “innovation champions”. When talking about innovation, the respondents were found to oscillate between performative narratives of innovation and more personalized stories derived from their own experience. The narratives were invariably pre-rehearsed often to the point of being monotonous. In contrast, the personalized stories tended to be engaging and emotionally laden. The tendency for senior executives to oscillate between narratives and stories is seen as an important means through which they search for meaning while at the same time legitimizing their self-identities as “innovation champions”. Of particular note is the way in which senior managers self-ascribe themselves with informal roles which are notably at odds with those described in more formalized narratives. 相似文献
45.
D. E. Dobson 《Building Research & Information》2013,41(2):93-97
When the new Office Building for the United States Embassy in Moscow was in the final construction stage, visible defects caused work on the building to be suspended; a detailed structural analysis was then carried out by the NBS Center for Building Technology. Its report highlights the problems that can arise both with a structural design — such as guarding against buckling and progressive collapse — and with the detailed execution of that design. 相似文献
46.
D. Mohan V. N. Singh S. N. Kaul Y. C. Sharma 《The International journal of environmental studies》2013,70(1):115-124
Feasibility of a waste material, flyash, as a material for purification of wastewater containing Lissamine Red has been studied. Effects of time and concentration, temperature and pH on the removal of the dye have been studied. Lower concentrations favour the uptake of dye from water and the maximum removal was observed at a dye concentration of 20 mgL m 1 , 30°C, pH of 7 and adsorbent particle size of 53 µm. Dynamics of the uptake was studied using Lagergren's equation. The mass transfer coefficient was found to be 0.05 cmmin m 1 at a concentration of 20 mgL m 1 , 30°C and 53 µm particle size. 相似文献
47.
D. J. Walmsley 《Urban Policy and Research》2013,31(4):509-523
Examination of the changing composition of shopping centres in suburban Sydney between 1969 and 1998 suggests that retail restructuring is linked to lifestyle changes. The growth in the number of shops appears to have matched population growth in the 1990s, suggesting that the suburbanisation of retailing has stabilised. At the same time there has been increasing diversification in terms of the retail functions which are available and in terms of the places where these are available. These changes appear linked to a blurring of the distinction between shopping and leisure and to the use of shopping as a way of signifying identity. 相似文献
48.
Kudashev S. V. Kondrasenko A. A. Maiulev A. N. Babkin V. A. Belousova V. S. Andreev D. S. Zheltobryukhov V. F. Kuznetsova N. V. 《Fibre Chemistry》2022,53(5):291-295
Fibre Chemistry - Modification of polycaproamide by 1H,1H,13H-trihydroperfluorotridecan-1-ol immobilized on montmorillonite produced an F-containing polymer composite. The structure of the... 相似文献
49.
Fibre Chemistry - Under modern conditions the creation of materials for sanitary hygiene and medical products based on cellulose is of paramount importance. Development and improvement in this area... 相似文献
50.
The emerging trends in the development of advanced smart materials with better unique properties under different environments for a particular application fascinate the researchers and industrialists. Nickel-Titanium based shape memory alloys are exotic materials due to their unique properties such as SME, SE, high damping characteristics, high corrosion and wear resistance and biocompatibility. This article presents an overview of machining processes that can be used to machine the NiTi and its surface induced characteristics such as microhardness, surface roughness, topography, induced layer, residual stress, fatigue and phase transformation. The surface integrity characteristics are discussed for machining of NiTi-SMAs under the category of traditional, non-traditional and micro-machining with the effect of input parameters such as cutting speed, feed, depth of cut, type of lubricant and type of coating material on cutting tool. The conventional machining of NiTi alloys are quite complicated due to high toughness, severe strain hardening, fatigue hardening and distinctive property of NiTi-SMAs such as pseudoelastic and shape memory effect. From this study, non-traditional process is significantly used to machine the NiTi-SMAs due to its better results on surface integrity characteristics. Consequently, future trends are also identified for machining the NiTi-SMAs and to improve the surface integrity characteristics. 相似文献