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排序方式: 共有610条查询结果,搜索用时 46 毫秒
101.
Prices of fuels such as coal and diesel are showing uptrend continuously in India due to which the manufacturing sector is finding it hard to control the production cost. The manufacturing units are emphasising upon innovative practices to reduce the electrical energy consumption in order to reduce production cost. They are recognising renewable energy as one of the options to save fuel cost to some extent by running some partial load on this energy. This paper is presenting a technical and economic analysis for proposing a hybrid renewable energy system, comprising Solar Photovoltaic, wind, a storage battery and a diesel unit, for running auxiliary load of a cement manufacturing unit located in Durg district of Chhattisgarh, India. As the diesel prices are continuously increasing almost rupees 0.5 per month in India for the last few months, the diesel price sensitivity analysis is also done for optimal system sizing. The results show that diesel price increment from $1.01 to $1.09 does not affect optimal system size but only net present cost and levelised cost of energy. When diesel price increases beyond $1.09, the optimal system size increases resulting in capital cost increment. It attains a new optimal system size at a diesel price of $1.13. 相似文献
102.
Gokhan Zengin Srinivasan Nithiyanantham Cengiz Sarikurkcu Sengul Uysal Ramazan Ceylan Karnam Satya Ramya 《International Journal of Food Properties》2017,20(10):2373-2382
In the present article, seven wheat cultivars (Ahmetaga, Bezostaya, Dagdas-94, Ekiz, Karahan-99, Konya-2002, and Tosunbey) grown in Turkey were compared for their phytochemical composition, antioxidant, and enzyme inhibitory activities. Antioxidant capacities and enzyme inhibitory effects were investigated with colorimetric methods. Total phenolic content ranged from 40.71 to 86.34 mg of gallic acid equivalent/100 g wheat grain. Tosunbey (92 mg Trolox equivalent/100 g wheat grain) and Ahmetaga (114.56 mg Trolox equivalent/100 g wheat grain) cultivars exhibited strong 2,2 azino-bis (3-ethylbenzothiazloine-6-sulfonic acid) and 1,1-diphenyl-2-picrylhydrazyl free radical scavenging activities. As compared to other wheat cultivars, Tosunbey cultivar had remarkable both antioxidant and enzyme inhibitory effects with the highest level of phenolics. Ferulic acid, chlorogenic acid, and apigenin were the major phenolics in extracts tested. This study suggested that an increased intake of wheat derived products could represent an effective strategy for the management of oxidative stress related chronic and degenerative diseases such as Alzheimers and diabetes mellitus. 相似文献
103.
Satya Narayan Tripathy B.G. Mishra Mandar M. Shirolkar S. Sen Suprem R. Das David B. Janes Dillip K. Pradhan 《Materials Chemistry and Physics》2013
Polycrystalline nano BiFeO3 powders were synthesized by auto-combustion method using urea as fuel and metal nitrates (Fe(NO3)3·9H2O, Bi(NO3)3·5H2O) as oxidizers. In order to optimize the single-phase synthesis condition of BiFeO3, different fuel to oxidizer ratios have been investigated. The preliminary structural investigation using X-ray diffraction shows the samples were of single phase and crystallize in rhombohedral structure (R3c). The ferroelectric and antiferromagnetic ordering temperatures of BiFeO3 were found to be 832 °C and 364 °C respectively, from differential thermal analysis. The temperature dependent dielectric study shows an anomaly around 215 °C which corresponds to magneto-electric coupling in the material. Field-emission scanning electron micrographs show effect of fuel to oxidizer ratio on grain size evolution. The ferroelectric hysteresis loops for all the samples were measured at a frequency of 100 Hz confirming the ferroelectric nature. An evidence of magneto-electric coupling was also observed at room temperature from magneto-capacitance measurements. 相似文献
104.
105.
Total productive maintenance (TPM) is an innovative approach to maintenance which holds the potential for enhancing effectiveness of production facilities. But, implementation of TPM is not an easy task. Innumerable barriers are encountered in real-life cases during TPM implementation. It is very essential to evaluate the nature and impact of these barriers so that production and maintenance managers can cultivate some strategies to overcome these barriers. In the present exertion, a graph theoretic approach has been applied to find the intensity of these barriers through an index which is computed through a permanent function obtained from the digraph of TPM barriers. 相似文献
106.
Hill KM Jonnalagadda SS Albertson AM Joshi NA Weaver CM 《Journal of food science》2012,77(8):H170-H175
Abstract: This study aimed to determine dietary vitamin D intake of U.S. Americans and Canadians and contributions of food sources to total vitamin D intake. Total of 7‐ or 14‐d food intake data were analyzed for vitamin D by a proprietary nutrient assessment methodology that utilized food intake data from the Natl. Eating Trends® service, portion size data from NHANES 1999–2004, and nutrient values using the Univ. of Minnesota's Nutrition Data System for Research software. Study participants were 7837 U.S. Americans and 4025 Canadians, ≥2‐y‐old males and females. The main outcome measures were total dietary vitamin D intake, percent contribution of foods to total vitamin D intake, and vitamin D intake by cereal and breakfast consumption habits. ANOVA was used to determine differences in means or proportions by age and gender and according to breakfast consumption habits. Mean vitamin D intake ranged from 152 to 220 IU/d. Less than 2% of participants in all age groups from the United States and Canada met the 2011 Recommended Daily Allowance (RDA) for vitamin D from foods. Milk, meat, and fish were the top food sources for vitamin D for both Americans and Canadians. Ready‐to‐eat (RTE) cereal was a top 10 source of vitamin D for Americans but not Canadians. Vitamin D intake was higher with more frequent RTE cereal and breakfast consumption in both countries, largely attributable to greater milk intake. Practical Application: Most U.S. Americans and Canadians do not meet the 2011 Inst. of Medicine recommended daily allowance (RDA) for vitamin D for their age groups from foods. Increasing breakfast and cereal consumption may be a useful strategy to increase dietary vitamin D intake to help individuals meet the RDA for vitamin D, particularly by increasing milk intake. However, it is likely that additional food fortification or vitamin D supplementation is required to achieve the RDA. 相似文献
107.
V. R. Giri Dev D. Thenmuhil T. Hemamalini S. Rahamedsara S. Shubhathra S. Vijayalaksmi 《纺织学会志》2020,111(6):821-825
AbstractNonwoven mats used for hemostat wound dressing was prepared by miniature wet laid nonwoven technique using wood pulp and kaolin. The wood pulp was dispersed along with kaolin in water medium and was wet laid by altering the process parameters. Optimum concentration of kaolin that can be loaded in the Web was found to be 2 gpl. The PBS swelling of the wood pulp/kaolin mat was 110% higher compared to the wood pulp control sample. The blood coagulation time for wood pulp/kaolin was 100?s whereas for the control sample was 250?s. The developed nonwoven mats have tremendous potential in trauma wound care. 相似文献
108.
Gitanjaly Goyal Harpreet Singh Surindra Singh Satya Prakash 《Metallurgical and Materials Transactions A》2011,42(11):3269-3276
Inhibitors and oxide additives have been investigated with varying success to control high-temperature corrosion. Effect of
Y2O3 on high-temperature corrosion of Superni 718 and Superni 601 superalloys was investigated in the Na2SO4-60 pct V2O5 environment at 1173 K (900 °C) for 50 cycles. Y2O3 was applied as a coating on the surfaces of the specimens. Superni 601 was found to have better corrosion resistance in comparison
with Superni 718 in the Na2SO4-60 pct V2O5 environment. The Y2O3 superficial coating was successful in decreasing the reaction rate for both the superalloys. In the oxide scale of the alloy
Superni 601, Y and V were observed to coexist, thereby indicating the formation of a protective YVO4 phase. There was a distinct presence of a protective Cr2O3-rich layer just above the substrate/scale interface in the alloy. Whereas Cr2O3 was present with Fe and Ni in the scale of Superni 718. Y2O3 seemed to be contributing to better adhesion of the scale, as comparatively lesser spalling was noticed in the presence of
Y2O3. 相似文献
109.
Rubeena Mungroo Vaibhav V. Goud Satya Narayan Naik Ajay K. Dalai 《European Journal of Lipid Science and Technology》2011,113(6):768-774
Green seed canola oil is underutilized for edible purposes due to its high chlorophyll content, which makes it more susceptible to photo‐oxidation and ultimately reduces the oxidation stability. The present work is an attempt to compare the kinetics of epoxidation of crude green seed canola oil (CGSCO) and treated green seed canola oil (TGSCO) with peroxyacids generated in situ in presence of an Amberlite IR‐120 acidic ion exchange resin (AIER) as catalyst. Among the two oxygen carrier studied, acetic acid was found to be a better carrier than the formic acid, as it gives 8% more conversion of double bond than the formic acid. A detailed process developmental study was then performed with the acetic acid/AIER combination. For the oils under investigation parameters optimized were temperature (55°C), hydrogen peroxide to double bond molar ratio (2.0), acetic acid to double bond molar ratio (0.5), and AIER loading (15%). An iodine conversion of 90.33, 90.20%, and a relative epoxide yield of 90, 88.8% were obtained at the optimum reaction conditions for CGSCO and TGSCO, respectively. The formation of the epoxide product of CGSCO and TGSCO was confirmed by Fourier Transform IR Spectroscopy (FTIR) and NMR (1H NMR) spectral analysis. 相似文献
110.