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91.
Biodiesel is a promising fuel for diesel engines in wake of its renewable nature and environmental benefits. Biodiesel can be produced by different pathways; however, glycerol (or glycerin, glycerin) is a valuable by-product which is formed during this process. As mandates are being enforced by different government worlds over, the demand of biodiesel is likely to go up. With increased demand and production of biodiesel, significant quantity of glycerol shall be available. There is an urgent need to find alternative application area of glycerol so that viability of biodiesel industry can be sustained.In the present study, the focus has been made on the various application areas of using surplus glycerol from biodiesel industries to make them more financially attractive. Amongst the different pathways of using glycerol as a source of energy; direct combustion, mixing with agricultural solid wastes and then burning, blending directly or indirectly with other fuels, hydrogen and hydrocarbon production from glycerol, etherification, etc. are prominent one. The requirement, advantages and limitations of each approach have also been evaluated in the study. Combustion of glycerol if not done properly would result in formation of acrolien which is highly toxic in nature and efforts should be made to use glycerol indirectly to produce energy (i.e. all the pathways expect the direct combustion and the solid fuel method). The production of hydrogen from glycerol via APR appears to be the best solution to the disposal problem since the hydrogen yield via APR is highest. Moreover the process occurs at lower pressure and temperature when compared to steam reforming, and it is a single step process. Etherification, tri-acetylisation, and blending have been found to be useful for improving the performance of automotives by facilitating proper and smooth combustion of fuel.  相似文献   
92.
Ground water is the principal source of drinking water in the rural areas of India. With the aim of determining, the contribution of (226)Ra to natural background radiation through drinking water exposure pathway near an operating uranium mining industry at Jaduguda, Jharkhand state of eastern India, the (226)Ra activity concentrations were measured in potable ground water. The water analysed, both tube well and well water, was collected in areas near the uranium industry and away. The (226)Ra concentration was measured by emanometric technique. The (226)Ra level in ground water was ranging between minimum detection limit of 3.5 mBq l(-1) and a maximum of 208 mBq l(-1). The analysis of variance reveals that there is insignificant statistical variation in the median (226)Ra concentration up to a distance of >10 km from the mining complex. Variation in concentration of (226)Ra in sources is attributed to the local geochemistry and environmental factors. The (226)Ra concentration was significantly elevated in natural artesian wells in the vicinity of uranium mineralised hill and it varies from 53.4 to 754 mBq l(-1). The WHO [Guidelines for Drinking Water Quality. Third Edition, Vol. 1, Recommendation (2004)] guideline value of 1000 mBq l(-1) has not been exceeded in any of the sources investigated.  相似文献   
93.
Fe-Cr based ferritic/martensitic (FM) steels are the candidate structural materials for future fusion reactors. In this work, a multi-scale approach comprising atomistic and dislocation dynamic simulations are used to understand the hardening of these materials due to irradiation. At the atomic scale, molecular dynamics (MD) simulations are used to study the mobility of an edge dislocation and its interaction with irradiation induced voids and bubbles. The dislocation dynamics (DD) simulations are used to estimate the change in flow stress of the material as a result of irradiation hardening. The key input to the DD simulations are the friction stress and maximum shear stress for the edge dislocation to overcome the defects as determined from atomistic simulations. The results obtained from the MD and DD simulations are in qualitative agreement with experimental results of hardening behavior of irradiated FM steels.  相似文献   
94.
Alloy steels of type 9Cr1Mo are being developed worldwide for the boiler and turbine components of supercritical and ultra supercritical thermal power plants and for the pressure vessel of fast breeder reactors. These steels exhibit very complex high temperature creep cavitation processes with coupled influences of creep strain, material softening and ageing etc. A new viscoplastic model considering both deformation and damage evolution has been developed in this work to predict high temperature creep deformation and damage of a 9Cr1Mo steel. Smooth tensile specimens have been analysed using this new model and the evolution of creep damage has been predicted. The results have been compared with those of experiment from literature. From the initial results, it is observed that this approach is very promising to carry out design and fitness-for-purpose of service of actual plant components.  相似文献   
95.
In this paper, we capture the moderating effect of aggressive driving behavior while assessing the influence of a comprehensive set of variables on injury severity. In doing so, we are able to account for the indirect effects of variables on injury severity through their influence on aggressive driving behavior, as well as the direct effect of variables on injury severity. The methodology used in the paper to accommodate the moderating effect of aggressive driving behavior takes the form of two models – one for aggressive driving and another for injury severity. These are appropriately linked to obtain the indirect and direct effects of variables. The data for estimation is obtained from the National Motor Vehicle Crash Causation Study (NMVCCS). From an empirical standpoint, we consider a fine age categorization until 20 years of age when examining age effects on aggressive driving behavior and injury severity.There are several important results from the empirical analysis undertaken in the current paper based on post-crash data collection on aggressive behavior participation just prior to the crash and injury severity sustained in a crash. Young drivers (especially novice drivers between 16 and 17 years of age), drivers who are not wearing seat belt, under the influence of alcohol, not having a valid license, and driving a pick-up are found to be most likely to behave aggressively. Situational, vehicle, and roadway factors such as young drivers traveling with young passengers, young drivers driving an SUV or a pick-up truck, driving during the morning rush hour, and driving on roads with high speed limits are also found to trigger aggressive driving behavior. In terms of vehicle occupants, the safest situation from a driver injury standpoint is when there are two or more passengers in the vehicle, at least one of whom is above the age of 20 years. These and many other results are discussed, along with implications of the result for graduated driving licensing (GDL) programs.  相似文献   
96.
The paper presents the electrical and thermo-mechanical design of single stage beam recovery system for 120 GHz, 1 MW gyrotron. The electrical study shows that the cylindrical shape single stage beam recovery system enhances the efficiency by 66.26%. The maximum power deposited to collector in depressed collector operation is 0.48 MW for electronic efficiency, 30% and 1.44 MW for DC electron beam. The thermo-mechanical analysis has been performed to evaluate the water cooling system. The cooling system has capability of accommodating a peak wall loading, 0.9 kW/cm2 at flow rate of 1500 l/min for safe operating time, 60 ms. Further, a high voltage analysis is also carried out to appraise the electric field distribution in the collector.  相似文献   
97.
Hempseed (HS) is rich in omega-3 polyunsaturated fatty acids, with approximately 17% of total fatty acids as alpha-linolenic acid. As such, HS and its oil may be used in hen diet formulations to produce eggs enriched in essential fatty acids. Because omega-3 eggs have the potential for unpleasant aromas and flavors, the current study was designed to assess the fatty acid profile and sensory attributes of eggs procured from hens consuming diets containing hempseed oil (HO) or HS. A total of 48 individually caged White Bovan hens received 1 of 6 diets containing 4%, 8%, 12% HO, 10%, 20% HS or 0% hemp (w/w) for 12 wk. Total omega-3 polyunsaturated fatty acid content was highest in the 12% HO group (15.3 mg/g of yolk) compared to the control (2.4 mg/g of yolk). Trained panellists (n= 8) found no significant differences (P≥ 0.05) in aroma or flavor between cooked eggs from different dietary treatments, with the exception of sweet flavor. The 4% HO group yielded the least sweet eggs compared to the 20% HS group, which was highest. For yolk color, L*, a*, and b* values (Mean ± SEM) for control eggs were 61.2 ± 0.10, 1.1 ± 0.05, and 43.0 ± 0.22, respectively. Addition of hemp led to significant (P < 0.001) reductions in L*, and significant increases in a* and b*, with the largest changes observed in the 20% HS treatment (L*= 58.7 ± 0.10; a*= 5.8 ± 0.05; b*= 60.5 ± 0.22). The results show that hemp use in hen diets leads to increased omega-3 polyunsaturated fatty acid content and color intensity of egg yolks, but does not have adverse effects on the sensory profiles of the cooked eggs. PRACTICAL APPLICATION: This study provides evidence that HS and hempseed oil (HO) can safely be utilized as feed ingredients for laying hens to produce table eggs that are enriched in essential fatty acids. Additionally, the eggs procured from these hens had similar aroma and flavor compared to eggs from hens not fed any hemp. The greater the dietary hemp inclusion, the more pigmented the resulting yolks became in terms of darkness, redness, and yellowness.  相似文献   
98.
99.
Novel sulfonated poly(ether ether ketone) (PEEK) copolymers were prepared using a low-viscosity grade PEEK powder. The TGA studies indicated that SPEEK membranes with up to 75% DS have enough thermal stability. The highest conductivity of 2.176 × 10?2 S cm?1 has been observed at 100°C for SP96 (DS = 72%). Compared to Nafion-15, SP72 exhibits much higher conductivity at all the temperatures considered. The water sorption experiments indicated that the maximum water uptake was 3.92% for SP24 and it was 60% for SP120. It was observed that the increase in the water content in a membrane caused a decrease in the diffusion coefficient.  相似文献   
100.
The effect of silane treatments on the water absorption properties of mercerized bamboo matting reinforced polyester composites were investigated. Treatments using γ-Aminopropyltriethoxy silane, 3-trimethoxysilylpropyl methacrylate, Vinyltris(2-methoxyethoxy)silane, Bis[3-(triethoxysilyl)propyl] tetrasulfide, 3-aminopropyltrimethoxy silane and n-Octyltrimethoxy silane were carried out to improve the water resistant property of the bamboo fibers. Water absorption in the composites was studied by long-term immersion and 2 h boiling in distilled water. The process of absorption of water was found to follow the kinetics and mechanism described by Fick's theory. Alkali treatment results in reduction of water absorption from 51% to 35%. Further reduction is observed with silane treatment. Water absorption varies between 19% and 44%, the minimum being for aminopropyl triethoxy silane-treated composites.  相似文献   
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