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121.
面向绿色制造的滚切工艺规划决策问题研究   总被引:1,自引:0,他引:1  
在对滚切加工的T(加工时间 )、Q(加工质量 )、C(加工成本 )、R(资源消耗 )、E(环境影响 )五个绿色制造目标特性分析的基础上 ,对面向绿色制造的滚切加工中的决策问题进行研究 ,并结合某企业滚切加工中的滚齿机设备选择问题进行案例分析  相似文献   
122.
A new structure of dicyanodistyrylbenzene-naphthalimide-based nonfullerene acceptor NIDCSN was synthesized and characterized to have a favorable electron accepting property and versatile processability in various organic solvents. The nonfullerene all-small-molecule solar cells comprising p-DTS(FBTTh2)2 as the donor and NIDCSN as the acceptor exhibited a maximum power conversion efficiency of 3.45% with a remarkable open-circuit voltage of 1.04 V, together with similar device performances when fabricated in five different solvents including environmentally benign non-halogenated ones.  相似文献   
123.
通过研究国内当前基于绿色视角的建筑设计实践,分析绿色建设的策略,从不同角度的案例来总结绿色建筑设计思想与策略,解析国内绿色建筑的建设方向与趋势,进一步深化对绿色建筑的认识。  相似文献   
124.
The effect of processing protocol on physical stability and the microstructure of water‐in‐oil‐in‐water multiple emulsions containing a mixture of two amphiphilic copolymers with opposed hydrophilic‐lipophilic balance as emulsifiers and a green solvent, 2‐ethylhexyl lactate, as the dispersed phase, has been assessed. Emulsions were obtained in at least two steps: a homogenization step by using a rotor‐stator device, followed by one or two homogenization steps carried out in a high‐pressure device that used microfluidizer technology. To study the microstructure and physical stability of these emulsions, a combination of different techniques, such as transmitted‐light optical microscopy, globule size distribution, viscous flow tests, and multiple light scattering measurements, were performed.  相似文献   
125.
Expansion of renewable energies in Germany is strongly associated with decentralization of energy provision. In the case of wind energy there are especially strong regional-level spatial, technical, economic, and social ramifications of this energy source. In addition to differing natural conditions and the strong push from the federal feed-in tariffs, policies and initiatives at the state, county, and municipal level need to be considered when explaining the pattern of wind energy expansion across time and space and to improve the coordination of multi-level energy policies. This paper uses panel regressions at the level of German counties from 2001 to 2012 to explore the growth of wind power capacity. Based on the estimates obtained, we then analyze counterfactual scenarios in which factors influenced by the regional (county) level are varied individually. Our focus is on party policy preferences and coalitions on the one hand, and the unemployment rate on the other. While strict causality is difficult to establish, our results reveal heterogeneous incentives between states, within states, and between different county types.  相似文献   
126.
This paper presents an efficient and stable green inverted organic light emitting diode (IOLED) using multifunctional and strong nucleophilic quality electron transport material (1,3-bis(2-phenyl-1,10-phenanthrolin-4-yl)benzene (m-bPPhenB)) with silver (Ag) as an n-dopant. By the energy level alignment study using in-situ ultraviolet photoelectron spectroscopy measurement, negligible electron injection barrier between indium tin oxide (ITO) and Ag-doped m-bPPhenB (Φe ≈ 0.03 eV) is observed and the electrons can be easily tunneled from ITO into Ag-doped m-bPPhenB layer. Also, Ag dopant forms coordination bonds with phenanthroline based unit, which improves electron injection from ITO. Fabricated IOLED devices using an Ag-doped m-bPPhenB have an extremely low driving voltage of 3.6 V and external quantum efficiency of 29.0%. Such good performances of IOLED are attributed to negligible electron injection barrier at the interface between ITO and Ag-doped m-bPPhenB. The Ag-doped IOLED device also shows a good air stability owing to the stable Ag n-dopant. The doping of Ag into special electron transport layer in the IOLED structure could be applicable to various displays and lighting applications.  相似文献   
127.
Hemodialysis is one of the most water and energy‐hungry medical procedures, and thus represents a clear opportunity where improvements should be made concerning the consumption and wastage of water. Three levels were investigated on which there are potential savings: the precise adjustment of water production according to specific needs, the reuse of reverse osmosis rejected water, and finally the huge volumes of post‐patient dialysate effluent. The “AURAL” (Association pour l′Utilisation du Rein Artificiel à Lyon), main unit in Lyon, was the site of investigation for this study, which cares for 173 chronic hemodialysis patients. Evaluation of the 3 levels described earlier was undertaken on this particular building, and on the water treatment currently used. Volumes of produced water can be improved by different hydraulic systems or by adjusting the pure water conductivity used for dialysis. Concerning the reject water, reuse for building sanitation became the focus of further attention. The technical feasibility, volume of saved water, and applicable work costs were considered. The results suggest that out of a possible 2834 m3/year of reject water, 1200 m3/year may be reused and return on investment recovered within 5.8 years. Finally, the reprocessing and feasibility of reuse of dialysate effluent were investigated. Initial calculations show that although technical solutions are available, such processing of the wastewater production is not profitable in the short term. Regarding the significant prior authorization and risk management analysis necessary for such a project, this avenue was pursued no further. From the perspective of a “green dialysis,” the reuse of reject water into sanitation is both viable and profitable in our unit, and must be the next step of our project. More widely, improvements can be made by defining a more precise range of pure water conductivity for dialysis and by applying reuse water project to new or to be renovated units.  相似文献   
128.
Consumers conventionally adopt diesel generation to meet the energy needs where the grid connection is unreliable or unavailable. While electrification has provided these communities a variety of economic and social opportunities, diesel consumption has resulted in adverse costs and environmental pollution. Two technologies available to reduce the expense and emissions of diesel fuel reliance include dual fuel or hybrid diesel applications. The dual-fuel approach involves a supplementary gas fuel charge in support of reduced diesel fuel consumption. Hybrid applications involve the integration of renewable generation to displace diesel fuel consumption. This paper reviews the potential for hybrid dual-fuel applications, identifying engine flexibility as a major integration barrier. In comparing the flexibility of various dual-fuel technologies to operate dynamically, this paper presents a critical review across hydrogen, liquified petroleum gas (LPG), natural gas (NG) and blended hydrogen and NG derivatives. The results identify a range of approaches able to improve engine flexibility and thus reduce the cost and carbon intensity of diesel-fired internal combustion engines. At low load conditions, while NG and LPG exhibit similar performance, the use of hydrogen and hydrogen blends provide improved engine performance and response. Unfortunately, given the current cost of hydrogen fuel, significant commercial barriers exist to the adoption of hydrogen or hydrogen blended fuels. Despite this, this review indicates the potential of hydrogen-NG blends to offer additional flexibility in comparison to alternative dual-fuel technologies. This position is furthered considering near term cost targets associated with the development of a global green hydrogen industry, coupled with its ability to serve as a demand-side management approach within isolated power systems, one of the multiple future research themes.  相似文献   
129.
The following paper is an analysis of the operating experiences during the initial phase of the 6 MW PEM electrolysis project “Energiepark Mainz”. The paper is divided into a technical and an economic evaluation. The technical evaluation contains the calculation of the efficiency of the Power-to-Gas plant based on the total power consumption, as well as the energy utilization factor. The economic evaluation analyses the different options of electricity procurement for the electrolysis. The three options, electricity purchase at the European power exchange, excess electricity from a direct marketing company, and participating in the control reserve market have been analysed. One first outcome shows, that economic feasibility can mainly be improved through participation in the secondary control reserve market.  相似文献   
130.
Iron (III) oxide nanoparticles were synthesized through green chemistry by the controlled reduction of hepta hydrous iron sulphate using the leaf extract of Garlic Vine. The crystalline phase of trivalent iron embedded in the primitive lattice of hexagonal β-Fe2O3 was obtained under the space group P3 (143). The scattered lines and considerably broadened peaks in the x-ray diffraction pattern indicate that the samples formed are crystallites of nano regime rather than bulk or amorphous in nature. Further, the size and the microstrain of the nanocrystallites were estimated through Hall Williamson analysis. The abundance of elemental iron present in the sample was estimated through Atomic Absorption Spectroscopy, whilst the UV visible analysis and FT-IR measurements, in accordance with XRD result, endorsed the formation of iron (III) oxide nanocrystals with iron predominantly occupying the octahedral sites. The band gap energy (2.84 eV) corresponds to the best fit is found to be for indirect allowed semiconducting transition between valance and conduction bands. Further, the TGA measurements were performed to identify the presence of capped polymer over the surface of nanoparticles, the organic decomposition temperature and phase transformation of meta-stable β-Fe2O3 to stable α-Fe2O3 at temperature above 500 °C.  相似文献   
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