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61.
We study the link between the indentation size effect and the density of geometrically necessary dislocations (GNDs) through the following approach: four indents of different depth and hardness were placed in a Cu single crystal using a conical indenter with a spherical tip. The deformation-induced lattice rotations below the indents were monitored via a three-dimensional electron backscattering diffraction method with a step size of 50 nm. From these data we calculated the first-order gradients of strain and the GND densities below the indents. This approach allowed us to quantify both the mechanical parameters (depth, hardness) and the lattice defects (GNDs) that are believed to be responsible for the indentation size effect. We find that the GND density does not increase with decreasing indentation depth but rather drops instead. More precisely, while the hardness increases from 2.08 GPa for the largest indent (1230 nm depth) to 2.45 GPa for the smallest one (460 nm depth) the GND density decreases from ≈2.34 × 1015 m?2 (largest indent) to ≈1.85 × 1015 m?2 (smallest indent). 相似文献
62.
Nader Tehrani Dan Gallagher Katie Faulkner Tim Wong Craig Chapple John Houser Ellee Lee Kevin Lee Parke MacDowell Ryan Murphy Jonathan Palazzolo Caitlin Scott Joana Rafael Rawan Alsane 《世界建筑导报》2018,(2)
正几个世纪以来,不同的地理环境一直都采用这类封闭的庭院形式——每一次都根据当地气候、风俗习惯和建筑实践进行改造。作为一种在建筑物内捕捉户外景观的手段,庭院由建筑内部结构决定。流畅的庭院不但提供内外部隐私保护,而且也不断地向外延伸,积极融入周边景观。该住宅遵守严格的分区指导方针,同时通过在屋顶上扩建自然植物区系与景观融合。坐落在橄榄树林、松树和葡萄园内,该住宅充分利用坡地,从而获得可持续的拓展和种植 相似文献
63.
The ozonation process has become one of the most favorable processes among soil remediation technologies nowadays. Ozone, which has an oxidation potential of 2.07 V and acts as a powerful oxidizer, is capable of degrading organic pollutants of soil in a short period of time without producing any toxic residuals. In this study the capability of ozone, as an ex-situ method of soil treatment, in remediating the leachate-contaminated soil has been investigated. To maximize the removal efficiency of organic content of soil, design of experiments using the response surface method (RSM) and central composite design (CCD) have been employed. To select the range of effective parameters several experiments were performed at laboratory scale. Results showed a range of effective parameters on the ozonation process, including pH, humidity, and initial soil pollution. Present research shows that acid-washed ozone greatly enhanced the removal efficiency. According to the developed model, the maximum removal efficiency using acid-washed ozone was obtained by setting the parameters as pH = 10.8, humidity of 5% and initial organic content of soil to be 7720 mg/kg. Confirmation experiments showed that RSM could be effectively utilized for the optimization of the ozonation process. Analysis of variance also showed that pH was the most significant factor affecting removal efficiency. 相似文献
64.
Journal of Housing and the Built Environment - Urban facilities within a neighborhood are among the most important factors affecting residential satisfaction. According to the definitions of... 相似文献
65.
Applicability of supramolecular polymers blending in preparation of materials with tunable properties is reported. The effect of strongly dimerising 2-ureido-4[1H]-pyrimidinone (UPy) end groups on phase compatibility in binary polymer blends was studied. A low molecular weight poly(tetrahydrofuran) diol was functionalized with UPy moieties (PTHF(UPy)2, a soft material) and mixed with varying amounts of low molecular weight UPy functionalized polycaprolactone di- and triol (PCL(UPy)2 and PCL(UPy)3, both relatively strong and stiff materials). Thermal studies showed that Tg of the homopolymers shifted to intermediate temperatures. AFM observation suggested that the phase domain decreased significantly after UPy functionalization of diols. Also the mechanical properties improved at a higher rate than those predicted by the rule of mixtures. These findings indicate that blend components are placed in intimate contact as a result of the UPy-UPy interactions. The reversible crosslinking by PCL(UPy)3 gave better control still over the mechanical properties of the supramolecular polymer blends. 相似文献
66.
Nader Ebrahimi 《Sequential Analysis》2013,32(3):213-227
Exact reliability analysis for complex repairable systems are usually difficult because of the complicated failure process that can result from repair policy. A common approach in practice is to use a simplified process such as the Power Law process which, although not exact, yields useful practical results. In this paper we consider the problem of determining a stopping time when estimating parameters of a Power Law process. The Bayes method is used in order to obtain an optimal time. 相似文献
67.
F.H. Nader 《Journal of Petroleum Geology》2011,34(2):135-156
This paper presents an updated review of the petroleum prospectivity of Lebanon. It is based on a re‐assessment of the tectono‐stratigraphic succession in Lebanon, correlation with nearby countries and the results of a recent offshore seismic survey. A generalized model illustrating potential petroleum system(s) in Lebanon is presented with data on Palaeozoic, Mesozoic and Cenozoic plays. Major lithological units are described with respect to their source, reservoir and cap‐rock potential. Based on a general review of previous studies and existing data, Lebanese exploration prospects may comprise on‐ and offshore as well as coastal (margin) targets. They include potential Triassic reservoirs in onshore central‐northern Lebanon including those at the Qartaba structure. Offshore plays are discussed with reference to recent seismic profiles; potential offshore targets comprise Oligo‐Miocene reservoirs sealed by Messinian evaporites as well as deeper Mesozoic reservoirs. 相似文献
68.
Over the past decades Lebanon's energy sector has been largely ignored and this has led to high economic and environmental costs. The sector is characterized by electricity poverty, an expanding and mainly unregulated transport sector and a lack of energy savings spanning through all sectors of the economy. Recently, the Government of Lebanon has committed to increase the share of renewable energy to 10% of the total energy supply by 2013 and to 12% by the year 2020; it also aims at reducing energy consumption by 6% by the year 2013. This paper aims at contributing to the formulation of a more comprehensive energy strategy for Lebanon by analyzing the recent changes in policy direction and by recommending legal, regulatory and policy measures in order to transform current shortcomings into opportunities allowing the country to become a regional ‘success story’ in the deployment of renewable energy and energy efficiency. 相似文献
69.
Md. Mustafizur Rahman Salma Parvin Md. Hasanuzzaman Rahman Saidur Nasrudin A. Rahim 《传热工程》2013,34(15):1249-1261
The mixed convection flow and heat transfer characteristics inside a square ventilated cavity with a heat-generating solid circular body located at the center have been investigated numerically. The inlet opening is at the bottom of the left wall, while the outlet one is at the top of the right wall, and all the walls of the cavity are considered to be adiabatic. A Galerkin weighted residual finite element method is used to solve the governing equations of mass, momentum, and energy. The behavior of the fluid in the ranges of dimensionless cylinder diameter from 0.1 to 0.6 of the heat generating body, thermal conductivity ratio range from 0.2 to 50 between solid and fluid, and heat generating parameter range from 1 to 5 is described in detail. The medium considered is air with a Prandtl number of 0.71. It is found that the flow and temperature field is strongly dependent on the already-mentioned parameters for the ranges considered. The variation of the mean Nusselt number, the dimensionless average drag force, and the average temperature of the fluid versus Richardson number are presented for these parameters. 相似文献
70.
Nader Ghaffari-Nasab Mohamad Saeed Jabalameli Mir Bahador Aryanezhad Ahmad Makui 《The International Journal of Advanced Manufacturing Technology》2013,67(9-12):2007-2019
The location-routing problem (LRP) is a relatively new research area within location analysis that concerns simultaneously both the problems of location of facilities and routing of vehicles among the established facilities and the demand points. In this work, we address the capacitated LRP with probabilistic travel times, which may arise in many practical contexts in logistics and supply chain management, and present some bi-objective mathematical programming formulations to model the problem using different stochastic programming approaches. The first objective is to minimize the overall system-wide costs, while the second objective concerns minimization of the maximum delivery time to the customers. In all the cases, the deterministic equivalents of the stochastic models have been extracted. To solve the resulted models, a variable neighborhood descent-based heuristic is proposed and finally computational study is performed and numerical results are reported. 相似文献