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121.
The insufficient hydropower resources along with the deleterious effects of thermal generations necessitate an ingenious scheduling scheme to comply with the growing power demand. The rapidly depleting coal reserve further strengthens the need to develop a new strategy to accomplish generation-load balance at minimum fuel cost over the scheduling horizon, in addition to ensuring reduced emissions. The existing approaches appear to offer suboptimal solutions or suffer from the computational burden due to the large number of problem variables involved. This paper presents an efficient economic emission dispatch strategy involving reduced number of decision variables for hydrothermal scheduling through the use of particle swarm optimisation. The results on three test systems highlight its superior performance and suitability for systems of any size. 相似文献
122.
H.S. Ramaswamy 《Drying Technology》2013,31(2):413-414
123.
Abstract The kinetics of moisture loss and solids gain during osmotic dehydration of blueberries under different conditions of temperature (37°C - 60°C), concentration of the sucrose solution (47°Brix - 70°Brix) and contact time between fruit and sucrose solution (0.5 h - 5.5 h) were studied, and modeled based on Fick's law of unsteady state diffusion. The study showed that all factors influenced moisture loss and solids gain (p<0.001), both generally increasing with temperature (T) and sucrose concentration (C). Based on the diffusion model, the calculated effective moisture diffusivity (Dm) ranged from 1.98 × 10?10 to 5.10 × 10?10 m2/s and the effective solids diffusivity (Ds) ranged from 2.54 × 10?11 to 2.22 × 10?10 m2/s. Both Dm and Ds showed increasing trends with temperature and sucrose concentration, and could be modeled as quadratic functions of T and C. 相似文献
124.
Considering this problem in relation to work in developing countries, the authors review an extensive literature and report on their own tests. The results highlight the aggressive effects of magnesium sulphate, but the experiments also show that a small quantity of bentonite added to the mixing water can effectively improve resistance. 相似文献
125.
ABSTRACT: The residence time distribution (RTD) was investigated using ultrasound during continuous ohmic heating of 1) starch solution and 2) carrot particles/starch solution mixtures. For liquid experiments, a copper pigment was used as a tracer. Ultrasonic sensors were placed at the end of the tube to measure changes in sound attenuation. The copper concentration was determined in samples taken at time intervals. For particulate foods, one kilogram of carrot/solution mixtures was introduced. Results of the ultrasonic method were compared to carrots weights in collected samples. Variations of sound attenuation illustrated well the RTD of solutions and carrot particles. Results of the ultrasonic method agreed with the pigment method for liquid and the gravimetric method for particulate foods. 相似文献
126.
The catastrophic failures of porcelain insulators in power lines can be minimized by understanding the structure-property
relationship that governs the performance. A study addressing the materials aspects has been conducted on alumina based porcelain
insulators used in 25 kV railway traction lines. This article asserts the controls exercised by chemical composition, crystalline
structural phases and microstructure on the functional reliability and durability of the insulators. Influences of the total
alumina, α-Al2O3 (corundum) and α-quartz contents, microstructural features including morphologies of mullite needles, quartz and corundum
grains in the alumino silicate glassy matrix, large inhomogeneities in matrix constituents and composition have been highlighted. 相似文献
127.
Electrical Conductivity of Cabbage and Daikon Radish as Affected by Electrical Voltage,Frequency, Salt Concentration and Temperature
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128.
P. Shah A.V. Ramaswamy K. Lazar Veda Ramaswamy 《Microporous and mesoporous materials》2007,100(1-3):210-226
A direct synthetic route for the preparation of Sn-SBA-15 materials with nSi/nSn ratios ranging from 100 to 10 under milder acidic conditions than normally employed for the preparation of Si-SBA-15 is reported. The changes in the pH conditions of the gel were made through an adjustment of the molar ratio of nH2O to nHCl (<1 pH <2) during preparation. The samples prepared under three different acidic conditions have been characterized by various techniques. An expansion of the lattice (powder XRD) and an increase in mesopore area (low temperature N2 adsorption) indicate that the hexagonal structure of the SBA-15 is maintained with no loss of long range ordering. The UV–vis reflectance spectra of Sn-SBA-15 samples show the presence of Sn4+ ions both in tetrahedral and octahedral environment. 29Si MAS NMR spectra of samples prepared under an intermediate acid condition show the presence of Q3 and Q4 species. Their ratio increases with a decrease in tin content. The presence of Si in (2Si, 2Sn) i.e., Q2 environment may point to incorporation of considerable Sn4+ ions in tetrahedral positions. Sn-Mössbauer spectroscopic studies reveal that Sn2+ species form upon reductive treatments and can probably be stabilized in the pore wall upon reoxidation. This to some extent is an indication of the formation and stabilization of Si–O–Sn–O–Si linkages in Sn-SBA-15. A progressive increase in the pH of the medium (increasing the nH2O to nHCl ratio) results in the location of Sn4+ ions, (a) at the surface of the mesopores (surface of the corona region) as a thin film of SnO2 or small aggregates (loss in mesopore area) depending on the concentration of Sn; (b) at the walls of the mesopore structure, substituting Si4+ ions (some lattice expansion and tetrahedral Sn4+ ions); and/or (c) as a part of the corona region, neutralizing the resulting Si–OH groups (a loss of micropore area and octahedral Sn4+ ions). The studies reveal that the method of preparation, nH2O/nHCl ratio and the nSi/nSn ratio (concentration of SnCl4) of the gel significantly influence the type of tin species in the resulting Sn-SBA-15 samples. 相似文献
129.
Jayeeta Saha Sonam Verma Ranadeb Ball Chandramouli Subramaniam Ramaswamy Murugavel 《Small (Weinheim an der Bergstrasse, Germany)》2020,16(12)
Compositional interplay of two different cobalt phosphates (Co(H2PO4)2; Co‐DP and Co(PO3)2; Co‐MP) loaded on morphologically engineered high surface area nanocarbon leads to an increased electrocatalytic efficiency for oxygen evolution reaction (OER) in near neutral conditions. This is reflected as significant reduction in the onset overpotential (301 mV) and enhanced current density (30 mA cm?2 @ 577 mV). In order to achieve uniform surface loading, organic‐soluble thermolabile cobalt‐bis(di‐tert‐butylphosphate) is synthesized in situ inside the nanocarbon matrix and subsequently pyrolyzed at 150 °C to produce Co(H2PO4)2/Co(PO3)2 (80:20 wt%). Annealing this sample at 200 or 250 °C results in the redistribution of the two phosphate systems to 55:45 or 20:80 (wt%), respectively. Detailed electrochemical measurements clearly establish that the 55:45 (wt%) sample prepared at 200 °C performs the best as a catalyst, owing to a relay mechanism that enhances the kinetics of the 4e? transfer OER process, which is substantiated by micro‐Raman spectroscopic studies. It is also unraveled that the engineered nanocarbon support simultaneously enhances the interfacial charge‐transfer pathway, resulting in the reduction of onset overpotential, compared to earlier investigated cobalt phosphate systems. 相似文献
130.
Ponnusamy Senthil Kumar Akshaya S. Nair Ananya Ramaswamy Anbalagan Saravanan 《IET nanobiotechnology / IET》2018,12(5):591
The present research is focused on the removal of Zn(II) ions from aqueous solution using nano zero‐valent iron impregnated cashew nut shell (NZVI‐CNS). The present system was investigated in batch mode operation. NZVI‐CNS was prepared by the liquid‐phase reduction process. The results showed that the NZVI‐CNS exhibited superior adsorption capacity for the removal of Zn(II) ions. Adsorption isotherm and kinetic models were applied to explain the nature of the adsorption process. Adsorption kinetic data followed the pseudo‐first order kinetic model. Moreover, the equilibrium adsorption data were best fitted with a Freundlich model. Langmuir monolayer adsorption capacity was calculated as 94.46 mg of Zn(II) ions/g of NZVI‐CNS. The thermodynamic parameters explain that the present adsorption system was measured as feasible and spontaneous. This newly prepared adsorbent can be successfully applied for the different industrial wastewater treatment. Finally, the exploration asks about contemplated that NZVI‐CNS has exhibited unrivalled adsorption limit. Additionally, NZVI‐CNS is believed to be extremely green and monetarily neighbourly help for wastewater treatment. The results indicate that the feasible approach could be applied in agricultural waste biomass materials for the productive expulsion of heavy metals from aqueous solution and reusing agricultural wastes to facilitate their disposal problem.Inspec keywords: wastewater treatment, contamination, zinc, reduction (chemical), adsorption, monolayers, renewable materialsOther keywords: nano zero‐valent iron impregnated cashew nut shell, aqueous solution, Zn(II) ion removal, NZVI‐CNS, batch mode operation, liquid‐phase reduction process, adsorption capacity, adsorption isotherm models, adsorption kinetic models, adsorption kinetic data, adsorption process, pseudo‐first order kinetic model, equilibrium adsorption data, Freundlich model, Langmuir monolayer adsorption capacity, thermodynamic parameters, adsorption system, industrial wastewater treatment, agricultural waste biomass materials, productive expulsion, heavy metals, waste disposal, Zn 相似文献