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51.
黄88支平1井是江苏油田第一口水平分支井,本文通过调研和理论研究,预测了该井的完井产能,优选了该井的完井方式、完井管柱以及完井配套工具,对今后江苏油田水平分支井的完井工艺具有一定的指导意义。  相似文献   
52.
在讨论建筑学的研究方法时总是存在很多疑惑,比如理论与设计的构成性和生成性的争论。而《建筑学研究方法》一书系统介绍了建筑学理论与研究方法方面的基础知识,本文结合作者曾经参与过的一次有关冬冷夏热地区(湖北)农村住宅热舒适性的调研实例,简要分析了一些建筑学理论研究中的普适性方法,并希望以此来探讨理论与实践之间的关系。  相似文献   
53.
概述了全球核电开发情况,介绍了高放废物地质处置国际态势及发展动向,对我国有关工作提出了意见和建议。  相似文献   
54.
In this study, the variation of the temperature distribution of the fuel plate in Tehran Research Reactor core was studied in case of coolant channels blockage. While the experimental method is not possible, both the analytical and simulation methods were used to obtain the more reliable data. The results show that one channel blockage will increase the fuel temperature to about 100%, but it does not lead to clad melt down still. With further calculation and simulation it is understood that if the coolant velocity drops to 90% of its nominal value, it may causes the clad melt-ing down. At least two channels with complete blockage even at the positions far from the core center can also melt down the clad.  相似文献   
55.
56.
铜作为重要的有色金属,它支撑着我国的现代化建设。作为全世界精铜需求最大的国家,我们的铜矿产资源却远远不能满足自身的生产需求,还需大量依靠进口铜矿产资源。此外,在现代化工业发展的今天,矿铜冶炼工艺也面临着环境污染等问题。因此,急需完成废杂铜等二次铜资源的再生利用研究。据报道,现在再生铜的产量已达到334万吨左右。废杂铜熔炼产物粗铜的电解精炼在一定程度上缓解了目前我国面临的资源供需矛盾,也可有效解决废杂铜资源堆积的问题,对铜冶炼双碳战略具有重要的研究意义和价值。  相似文献   
57.
The physical process of jamming could take architectural sustainability/recyclability to a whole new level. It involves achieving structural rigidity through the crowding of particles within a confined space, rather than by permanent bonding. Project Z-Form, a collaboration between a team of physicists from the JaegerLab at the University of Chicago – including PhD students Kieran Murphy and Leah Roth and professor Heinrich Jaeger – and artist Dan Peterman , sets out to develop a pourable material that not only self-supports but can also bear loads. Here they explain the project and the concepts behind it.  相似文献   
58.
One of the oldest continuously inhabited cities on the planet, Aleppo now lies in tatters. This devastation of a designated World Heritage Site is a poignant example of the human and cultural cost of armed conflict – in this case the Syrian Civil War. A project run by the Center for Spatial Research at the Graduate School of Architecture, Planning and Preservation of New York's Columbia University is analysing satellite imagery and reports from the ground to assess the damage and casualties caused there by barrel bombs. Associate Professor Laura Kurgan describes the initiative and its sometimes puzzling findings.  相似文献   
59.
Can artificial materials be developed that rival nature's ability to self-assemble and self-replicate? Zorana Zeravcic, lecturer and researcher at the École Supérieure de Physique et de Chimie Industrielles Paris Sciences et Lettres Research University in Paris, outlines investigations on the subject being carried out by her department and by counterparts at Harvard University in the US. Drawing on methodologies and knowledge from across the sciences, their simulations have yielded previously unenvisioned complex functionalities that could transform the way we build.  相似文献   
60.
As a novel strategy to improve heat transfer characteristics of fluids by the addition of solid particles with diameters below 100 nm, nanofluids exhibit unprecedented heat transfer properties and are being considered as potential working fluids to be used in high heat flux systems such as electronic cooling systems, solar collectors, heat pipes, and nuclear reactors. The present paper reviews the state-of-the-art nanofluid studies on such topics as thermo-physical properties, convective heat transfer performance, boiling heat transfer performance, and critical heat flux (CHF) enhancement. It is indicated that the current experimental data of nanofluids thermal properties are neither sufficient nor reliable for engineering applications. Some inconsistent or contradictory results related to thermo-physical properties, convective heat transfer performance, boiling heat transfer performance, and CHF enhancement of nanofluids are found in data published in the literature. No comprehensive theory explains the energy transfer processes in nanofluids. To bridge the research gaps for nanofluids' engineering application, the urgent work are suggested as follows. (1) Nanofluid stability under both quiescent and flow conditions should be evaluated carefully; (2) A nanofluid database of thermo-physical properties, including detailed characterization of nanoparticle sizes, distribution, and additives or stabilizers (if used), should be established, in a worldwide cooperation of researchers; (3) More experimental and numerical studies on the interaction of suspended nanoparticles and boundary layers should be performed to uncover the mechanism behind convective heat transfer enhancement by nanofluids; (4) Bubble dynamics of boiling nanofluids should be investigated experimentally and numerically, together with surface tension effects, by considering the influences of nanoparticles and additives if used, to identify the exact contributions of solid surface modifications and suspended nanoparticles to CHF enhancement in boiling heat transfer. Once we acquire such details about the above key issues, we will gain more confidence in conducting application studies of nanofluids in different areas with more efficiency.  相似文献   
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