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81.
Guo W. Cao S. Zeng L. Xia M. Wang Y. Li J. 《Metallurgical and Materials Transactions A》2021,52(12):5152-5158
Oriented materials are of great importance, but their formation is rarely described. Here, nine Al/Al2O3 systems were designed to identify the dominant factors. Electron back-scattered diffraction indicates that the new Al crystal(s) with one or multiple orientation(s) can be stimulated by one single-crystal Al2O3 substrates. Synchrotron radiation diffraction shows that the preferred orientation(s) is/are determined based on the initial stage of the liquid–solid transition. The nonpreferred orientation can be suppressed through competition.
相似文献82.
Sudin V. V. Stepanov P. P. Bozhenov V. A. Kantor M. M. Efron L. E. Zharkov S. V. Chastukhin A. V. Ringinen D. A. 《Metallurgist》2021,65(5-6):500-516
Metallurgist - Microstructural mechanisms reducing the impact strength values of a coarse grained heat-affected zone are studied for two K60 microalloyed steels. Research is conducted on specimens... 相似文献
83.
Metallurgist - The article provides a brief assessment of the current state of power supply units at metallurgical plants and prospects for their future development. The principal power-supply... 相似文献
84.
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86.
随着交通量不断增长,车辆重载、超载现象日益严重。沥青路面通车一段时间后,常常出现不同程度的横向裂缝。分析了沥青路面横向裂缝产生的原因和危害,同时提出了相应的裂缝防治措施。 相似文献
87.
K.E. LANSEY C. BASNET L. W. MAYS J. WOODBURN 《Civil Engineering and Environmental Systems》2013,30(3):211-226
The scheduling of maintenance for water distribution systems is a complex task encompassing a wide range of alternatives. The methodology presented in this paper can consider the major piping alternatives of replacing and cleaning, and relining. It also considers the potential of pumping improvements while accounting for the costs of maintenance, failure and operations for a multiple-period planning horizon. To solve the problem a nonlinear optimization model is linked with a network simulation model. The application showed that the procedure can determine solutions in reasonable times. 相似文献
88.
Gül Asatekin 《The Journal of Architecture》2013,18(4):389-414
Traditional architecture and associated environments created by residential buildings provide an important focus of interest in contemporary Turkey.1 They are generally accepted as physical witnesses of the past to be preserved and studied. Continuity in the traditional characteristics of the social group living in these environments has been observed in many of the extant settlements in Turkey. The reciprocal relationship between the dwelling and its owners, or users, has led to a dual definition of the ‘traditional dwelling unit’: the social unit being the ‘family’, the architectural unit the ‘dwelling’. The existing, modest-scaled, traditional dwellings in Turkey, which constitute the subject of this study, were mostly constructed after the seventeenth century, but more recent buildings exhibiting similar characteristics are also covered by the term ‘traditional’.2 The concept of ‘privacy’ serves as the basis of evaluation in analysing the interrelation of any two units. The interface of two units can be defined as an hierarchy of privacy represented sociologically by the interrelations of person/family/neighbourhood relationships and architecturally through the interrelations of room/dwelling unit/street/neighbourhood.3 This approach will include a brief summary of some previous studies of traditional residential architecture (Fig. 1). 相似文献
89.
I.P.L. Coleman J.A. Blair M.E. Hilburn 《The International journal of environmental studies》2013,70(3-4):187-191
The effect of a number of dietary and synthetic chelating agents on the intestinal absorption of lead has been examined using the everted sac preparation and the tracer isotope 203Pb. All the agents examined increased lead transport into the serosal compartment. An explanation of the way in which these agents modify the model to describe lead transport is proposed. 相似文献
90.
John R. Hamburg Roger L. Creighton 《Journal of the American Planning Association. American Planning Association》2013,79(2):67-72
The planning of community facilities requires accurate quantitative estimates of the area, type, intensity, and location of land uses required by the growth of urban activities. The distribution of these activities and the intensity of their use of land are highly related to accessibility as measured by distance from the CBD. This paper outlines a procedure whereby area-wide estimates of future population and economic activity can be distributed to small subareas so that measures of local land requirements may be obtained. 相似文献