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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.
Russian Journal of Non-Ferrous Metals - Using a Thermo-Calc software package (TCAl4.0 database), unexplored data concerning the phase composition and crystallization behavior of...  相似文献   
84.
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   
85.
Russian Journal of Non-Ferrous Metals - In this paper, using the AA 511 alloy of the Al–Mg–Si system as an example, it is shown that the irradiation of aluminum melts with nanosecond...  相似文献   
86.
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   
87.
Powder Metallurgy and Metal Ceramics - The phase composition, type II microstresses, and coherent scattering domains (CSDs) of multicomponent (medium- and high-entropy) bcc solid solutions with an...  相似文献   
88.
Infrastructure planning for Urban Water Systems (UWSs) is challenged by, inter alia, increasing uncertainty in both demand and availability of water and aging infrastructure, and this is already impacting the climate-proofing of cities. In this context, the idea of resilience has been gradually embraced by the water sector, but the term itself is not yet universally defined, nor operationalised. Here, we propose a methodology to assess the resilience of a UWS, defining it as the degree to which the UWS continues to perform under increasing stress. A resilience assessment method is then proposed as a ‘stress-test’ of UWS configurations, under increasingly more stressful scenarios. We then demonstrate a toolbox assembled for the proposed analysis using, as a proof of concept, a semi-synthetic case study. Results are promising, suggesting that the approach could assist in the uptake and evolution of resilience thinking in strategic water infrastructure decision making, leading to water-wiser cities.  相似文献   
89.
The choice of an appropriate procurement system is crucial to construction project success. Procurement selection is largely based on path determination charts, with at least eight key criteria needing to be weighted by decision-makers. Including certain criteria whilst ignoring client-borne transaction costs (TCs) resulting from environmental uncertainties simplifies this process. TCs are ‘unseen’ costs associated with pre- and post-contract work. The effects of uncertainties in the transaction environment and procurement systems on TCs are investigated, comparing the traditional and design-build procurement systems. A cross-sectional sample approach was deployed, involving survey questionnaire and results verification through ‘real-world’ cases. Data was sought from construction professionals in management, design and operation of construction projects. The research participants evaluate their time spent on procurement activities using a five-point Likert scale. Hypotheses of the relations between environmental uncertainties, procurement systems, and pre- and post-contract TCs are tested using a structural equation modelling (SEM) approach. The study found that TCs account for about 46.75% and 42.88% of the daily time spent by project managers in traditional and design-build procurement systems in New Zealand respectively. The study concludes that the TC concept is a useful framework for determining objective instead of subjective opinions for procurement decisions.  相似文献   
90.
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   
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