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91.
The current research work presents a facile and cost–effective co-precipitation method to prepare doped (Co & Fe) CuO and undoped CuO nanostructures without usage of any type of surfactant or capping agents. The structural analysis reveals monoclinic crystal structure of synthesized pure CuO and doped-CuO nanostructures. The effect of different morphologies on the performance of supercapacitors has been found in CV (cyclic voltammetry) and GCD (galvanic charge discharge) investigations. The specific capacitances have been obtained 156 (±5) Fg?1, 168(±5) Fg?1 and 186 (±5) Fg?1 for CuO, Co-doped CuO and Fe-doped CuO electrodes, respectively at scan rate of 5 mVs?1, while it is found to be 114 (±5) Fg?1, 136 (±5) Fg?1 and 170 (±5) Fg?1 for CuO, Co–CuO and Fe–CuO, respectively at 0.5 Ag-1 as calculated from the GCD. The super capacitive performance of the Fe–CuO nanorods is mainly attributed to the synergism that evolves between CuO and Fe metal ion. The Fe-doped CuO with its nanorods like morphology provides superior specific capacitance value and excellent cyclic stability among all studied nanostructured electrodes. Consequently, it motivates to the use of Fe-doped CuO nanostructures as electrode material in the next generation energy storage devices.  相似文献   
92.
It has previously been shown that the cattle brain is supplied with blood via a basi-occipital plexus, in addition to branches from the carotid and basilar arteries. In addition it has been shown during conventional stunning and slaughter that the carotid arteries in cattle can develop false aneurysms at their severed ends and this can curtail exsanguination. This investigation examined whether false aneurysms can occur during religious slaughter, and during bleeding following electrical stunning that simultaneously induced a cardiac arrest. The prevalence of large (>3 cm outer diameter) false aneurysms in cattle carotid arteries was 10% for both shechita and halal slaughter. The prevalence of animals with bilateral false aneurysms (at least 2 cm in one artery and at least 3 cm diameter in the opposite artery) was 7% and 8% for shechita and halal slaughter, respectively. No false aneurysms occurred during bleeding in cattle that were electrically stunned and simultaneously developed a cardiac arrest. The combination of false aneurysms and collateral routes to the brain present a risk of sustained consciousness during religious slaughter in cattle.  相似文献   
93.
The composite bipolar plates are developed using natural graphite, carbon black, and carbon fiber, along with 1% graphene with phenol formaldehyde (resole) resin. The graphene is developed by thermo-chemical exfoliation of natural graphite and characterized by XRD, Raman, FESEM, and AFM analyses. The synthesized graphene is monolayer graphene with a minimum thickness of 1 Å. The bipolar plates are developed using compression molding technique and thoroughly characterized considering stringent benchmarks (US-DOE and Plug Power Inc.) for PEMFC viz., electrical conductivity, flexural strength, deflection at mid-point, and corrosion current density. The composite bipolar plate showed excellent corrosion resistance to the rigorous fuel cell environment. All the required properties are achieved by the developed composite bipolar plate for PEMFC application. The fuel cell is fabricated with the developed bipolar plate and the performance of the fuel cell is studied. The incorporation of graphene has improved the fuel cell performance significantly.  相似文献   
94.
In 2005, the major economies of the world, including the G8 and 5 developing nations (Mexico, India, Brazil, China, and South Africa), along with the United Nations, the International Energy Agency, and the European Union launched the Global Bioenergy Partnership to discuss ways to promote the sustained use and production of biofuels around the globe, reflecting growing concerns for finding economically viable substitutes for petroleum. This paper examines whether and if a vibrant global market in biofuels based on sugarcane-based ethanol is economically feasible. The paper finds that while there is already international trading in biofuels, it is highly limited compared with its potential. In the current climate of accelerating fossil fuel prices, biofuels represent an increasingly attractive displacement for some of our fossil fuel addiction. Not only do they substitute for petrol, but they also produce lower emissions. The paper finds that sugarcane ethanol could make an important contribution to substituting for a portion of petroleum and also offer potential benefits for international development.  相似文献   
95.
This paper presents an approach to find the best modification in the coal-based sponge iron process with an aim to integrate energy in it. For this purpose, a few energy conservation cases are formulated by integrating unutilized energy present in possible areas of process flow sheet. When unutilized energy of the process is properly integrated, energy demand from outside sources can be reduced. It decreases coal consumption as coal is the only source of energy in this plant. For energy integration in sponge iron process pinch technology is applied on the actual data of plant. Based on this data, seven energy conservation cases are identified. Among these, two are selected for detailed analysis based on utility requirement. For these two cases capital investment required for energy integration, coal consumption, water requirement, energy consumption, profit, and payback period are compared. Based on these factors the best case is selected. The integrated design for the best case includes air preheating and cooling of kiln outlet using waste gas. Further, a modified case is discussed with preheating of feed to rotary kiln and air using waste gas. This case consumes 12.3% and 93.7% less energy and water, respectively, and gives 8.6% more profit in comparison to the previous case. Thus, the modified design is selected as the best option for energy integration. This design also satisfies the practical constraints of the process.  相似文献   
96.
Varying proportions of hydrogen and carbon monoxide (synthesis gas) have been investigated as a spark ignition (SI) engine fuel in this paper. It is important to understand how various synthesis gas compositions effect important SI combustion fundamentals, such as knock and burn duration, because in synthesis gas production applications, the compositions can vary significantly depending on the feedstock and production method.A single cylinder cooperative fuels research (CFR) engine was used to investigate the knock and combustion characteristics of three blends of synthesis gas (H2/CO ratio); 1) 100/0, 2) 75/25, and 3) 50/50, by volume. These blends were tested at three compression ratios (6:1, 8:1, and 10:1), and three equivalence ratios (0.6, 0.7, and 0.8).It was revealed that the knock limited compression ratio (KLCR) of a H2/CO mixture increases with increasing CO fraction, for a given spark timing. For a given equivalence ratio and spark timing, a 50%/50% H2/CO mixture produced a KLCR of 8:1 compared to a 100% H2 condition, which produced a KLCR of 6:1. The burn duration and ignition lag is also increased with increasing CO fraction. The results from this work are important for those considering using synthesis gas as a fuel in SI engines. It reveals that although CO is a slow burning fuel, higher CO fractions in synthesis gas can be beneficial, because of its increased resistance to knock, which gives it the potential of producing higher indicated efficiencies through the utilization of an engine with a higher compression ratio.  相似文献   
97.
一种新型感应电阻率测井仪器能够提供远离井筒地层的三维信息,提高斜井和倾斜地层的电阻率测量精度,而且不需要接触井壁就能够直接测量地层倾角大小和方位。采用这种高精度三轴电阻率测井仪器可以减少漏掉油气层的机会,加强对储层的认识。  相似文献   
98.
Energy demand of India is continuously increasing. Coal is the major fossil fuel in India and continues to play a pivotal role in the energy sector. India has relatively large reserves of coal (253 billion tonnes) compared to crude oil (728 million tonnes) and natural gas (686 billion cubic meters). Coal meets about 60% of the commercial energy needs and about 70% of the electricity produced in India comes from coal, and therefore there is a need for technologies for utilization of coals efficiently and cleanly. UCG offers many advantages over the conventional mining and gasification process. UCG is a well proven technology. Due to the site-specific nature of the process, possibility of land subsidence and surrounding aquifer water contamination, this technology is still in a developing stage in India. Potential for UCG in India is studied by comparing the properties of Indian coals with the properties of coal that are utilized by various UCG trials. The essential issues are elaborated for starting UCG in India based on the reported information from the successful field trials conducted all over the world. Indian industries are in the process of initiating pilot studies of UCG at various sites. This study will help to motivate both applied and theoretical research work on UCG sites in India and after detailed analysis it will provide basic data to interested industries.  相似文献   
99.
100.
This study reports the results of a numerical investigation of turbulent natural convection in a square enclosure with localized heating from below and symmetrical cooling from the vertical side walls. The present study simulates the case of an accidental heat generation due to fire in a typical isolated building of a nuclear reactor or electronic components cabin. The source of fire is considered to be centrally located at the bottom wall with different heated widths, which is assumed to be either isothermal or with isoflux. For the purpose of the analysis, the source length is varied from 20 to 80% of the total width of the bottom wall. The top wall and the unheated portion of the bottom wall are considered to be adiabatic, whereas sidewalls are isothermal. Steady as well as transient forms of two-dimensional Reynolds–Averaged-Navier–Stokes equations and conservation equations of mass and energy, coupled with the Boussinesq approximation, are solved by the control volume based discretisation method employing the SIMPLE algorithm for pressure–velocity coupling. Turbulence is modeled using the standard kε model. Rayleigh number, Ra, based on the enclosure height is varied from 108 to 1012. Stream lines and isotherms are presented for various combinations of Ra and the heated width. A double cell flow pattern is observed with marginal loss in symmetry as Ra increases. The results are reported in the form of local and average Nusselt number on the heated floor. Correlations are developed to predict the heat transfer rates from the enclosure as a function of dimensionless heated width of the bottom wall and Ra, by least square linear regression analysis.  相似文献   
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