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《Ceramics International》2022,48(12):16944-16955
Herein, the influence of the impact angle and Ni content on the wear behavior of Mo2NiB2–Ni cermets was studied using an erodent-carrying slurry comprising artificial seawater and SiO2 sands. The results reveal that the material loss may be attributed to the wear damage caused by SiO2 sands because cermets are expected to exhibit good corrosion resistance in artificial seawater. The relative density of cermets markedly influences their resistance to wear damage, and the material loss experienced by cermets with poor relative density is 2–4 times higher than that of cermets with good relative density; this occurs because a higher relative density can markedly enhance the mechanical properties and reduce the defects in the cermets. Moreover, the results indicate that as the impact angle increases from 0° to 60°, the manifestation of the wear mechanism changes from damaging the Ni binder phase (caused by single cutting wear) to damaging both the Mo2NiB2 ceramic and Ni binder phases due to the combination of cutting wear and impact wear. The wear damage is dominated by the cutting wear and impact wear from SiO2 sand at the low and high impact angles, respectively. Furthermore, the severe deterioration of the single ceramic skeleton at high impact angles indicates that the synergistic influence of the Mo2NiB2 ceramic and Ni binder phases on enhancing the wear resistance of the cermets intensifies at high impact angles. 相似文献
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从黄柏河东支流域磷矿山绿色开发要求出发,基于地表水环境系统和矿业开采的耦合影响作用,开展了磷矿山开采对黄柏河东支的水环境的影响研究。通过定量和定性分析,在磷矿山开采过程中对黄柏河东支的各种影响因素中,矿井涌水(占比为43.19%)、尾渣淋溶水(占比为15.51%)、矿废石淋溶水(占比为14.64%)和生产废水(占比为10.84%)为磷矿山开采对黄柏河东支水环境的主要影响因素,尤其是矿井涌水携带的总污染物量大,影响占比接近50%。该研究影响分析为黄柏河东支水环境的治理提供有力指引支撑。 相似文献
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为满足简便检测塑料产品抗冲击强度的需求,研制了垂直冲击试验机。对垂直冲击试验机的结构进行了设计,基于力学原理进行了受力计算,并对工作原理与相对基准设定问题进行了分析。介绍了垂直冲击试验机的操作方法,并进行了规格校验。 相似文献
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??The microstructure and properties of die steels with Ti and without Ti at different austenitizing temperatures were studied through the combination of thermodynamic calculation and experiment. The results show that the total solution temperature of Cr23C6, Cr7C3, VC, V2C, V8C7, MoC, Mo2C and TiC is 748. 2, 952. 7, 977. 3, 632. 9, 1116. 0, 1131. 2, 645. 3 and 1044. 1??, respectively. Hardness and impact toughness both increase with the increase in temperature. When the austenitizing temperature is above 1200 ??, it has a greater influence on the hardness. Toughness of die steel with Ti is better than that without Ti. The grain becomes coarse and the amount of martensite increases with the increase of temperature. The average grain size of the die steel with Ti is 21. 4??m smaller than that without Ti, and the size of the undissolved phase of the former is about 0. 2??m smaller than that of the latter. 相似文献
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Nikolaos Gavanas Efthimios Moutsiakis Anastasia Tasopoulou Eleni Verani Vasilios Fourkas 《影响评估与项目评价》2018,36(4):294-307
Territorial Impact Assessment (TIA) is proposed as a critical tool in order to investigate the way policies affect spatial development and hence territorial cohesion. The paper introduces a TIA methodological model in relation to transport sector. The design of the methodological model is based on a quantitative evaluation framework that comprises a set of selected indicators applied in a cross-border area of southeast Europe, influenced by the operation of the Greek motorway system of Egnatia and its vertical axes. The indicators are grouped into three main fields of TIA, i.e. transport intermodality, polycentric spatial organization and cross-border territorial cooperation. The TIA’s indicators are approximated by quantitative analysis. The procedure concludes to an overall composite indicator measuring the ‘level of territorial cohesion’ along with some core results and the expected added value. It also highlights some key technical aspects about the routines used and proceeds to suggestions for further refinement. 相似文献
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Abhendra K. Singh Kaitlyn Kahle Hannah James Allison L. Horner Daniel Villaflor Zach Benedict 《Ceramics International》2021,47(12):17268-17275
In this study the effects of high temperature and moisture on the impact damage resistance and mechanical strength of Nextel 610/alumina silicate ceramic matrix composites were experimentally evaluated. Composite laminates were exposed to either a 1050°C isothermal furnace-based environment for 30 consecutive days at 6 h a day, or 95% relative humidity environment for 13 consecutive days at 67°C. Low velocity impact, tensile and short beam strength tests were performed on both ambient and environmentally conditioned laminates and damage was characterized using a combination of non-destructive and destructive techniques. High temperature and humidity environmental exposure adversely affected the impact resistance of the composite laminates. For all the environments, planar internal damage area was greater than the back side dent area, which in turn was greater than the impactor side dent area. Evidence of environmental embrittlement through a stiffer tensile response was noted for the high temperature exposed laminates while the short beam strength tests showed greater propensity for interlaminar shear failure in the moisture exposed laminates. Destructive evaluations exposed larger, more pronounced delaminations in the environmentally conditioned laminates in comparison to the ambient ones. External damage metrics of the impactor side dent depth and area directly influenced the post-impact tensile strength of the laminates while no such trend between internal damage area and residual strength could be ascertained. 相似文献
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ABSTRACTSocial licence to operate (SLO) is a term that is finding increasing acceptance in a number of industries. Like all new terms, its precise meaning and implications are still being investigated. Using data from previous studies, this paper offers an analysis of the SLO of two case studies with each study being viewed separately through the grid of a distinct theoretical framework. Case study 1 looks at the development of differential social licence negotiated in the Hamlet of Cambridge Bay, Nunavut, as a result of an impact and benefit agreement negotiated between Tahera Diamond Corp. and the Kitikmeot Inuit Organisation in 2004. The study demonstrates that general acceptance of resource development can be uneven and reflect an unequal distribution of decision-making power. In case study 2, stakeholders of a failed mineral development project were queried across time about the specifics of the proposed mine development and were queried about resource development across different levels of consciousness. Perhaps, SLO is variable across different levels of consciousness. The paper concludes with observations about the variable nature of SLO acceptance across populations and across levels of consciousness within individuals. Perhaps, the concept of SLO is, in fact, complex, difficult to define and measure and, at this point, of limited utility as a measure of resource development acceptance. 相似文献