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排序方式: 共有677条查询结果,搜索用时 31 毫秒
121.
B.B. Sahoo N. Sahoo P. Mahanta L. Borbora P. Kalita U.K. Saha 《Renewable Energy》2008,33(7):1703-1708
Fluoride contaminated drinking water is a severe problem in many parts of the world because of fluoride-related health hazards, which are considered to be a major environmental problem today. The present work is aimed at utilizing solar energy for removal of fluoride from drinking water by using a “solar still”. Also tests have been conducted with the “solar still” to find out hourly output rate and “still efficiencies” with various test matrixes. It is observed that the distillate from “solar still” showed a fluoride reduction of 92–96%. Further, the efficiency of “solar still” got increased by 11% when capacity of water in the solar basin was raised from 10 to 20 L. Upon suitable modification of the solar basin with appropriate base liner and insulation, this efficiency of the “solar still” is found to be further increased by 6% with a 20 L basin capacity. 相似文献
122.
P. Poddar S. Mukherjee K.L. Sahoo 《Journal of Materials Engineering and Performance》2009,18(7):849-855
In the present study, rheocasting process was adopted to synthesise AZ91D composites reinforced with silicon carbide (SiC)
particulates. Particle-matrix interfacial reaction, distribution of particles, hardness and mechanical properties of as cast
and T4 heat-treated alloy-composites were reported. The rheocast composite materials reveal uniform distribution of SiC particulates.
The composite materials show an increase in hardness and elastic modulus compared to unreinforced rheocast alloy. Τhe ultimate
tensile strength and ductility of composite materials were lower than those of the unreinforced alloy. 15 μm particles-composite
shows significantly higher elastic modulus than the 150 μm SiC particles-composite. 相似文献
123.
Trapping and Generation of Waves by Vertical Porous Structures 总被引:3,自引:0,他引:3
The trapping and generation of surface waves by submerged vertical permeable barriers or plates kept at one end of a semi-infinitely long channel of finite depth are investigated for various barrier and plate configurations. The various fixed barrier configurations are (1) a surface-piercing barrier; (2) a bottom-touching barrier; (3) a barrier with a gap; and (4) a fully submerged barrier. The different moving plate (or wavemaker) configurations are of types 1, 2, and 4, respectively. The boundary value problems are converted to dual∕triple series relations by a suitable application of the eigenfunction expansion method and then the full solutions are obtained by the least-squares method. The variations of reflection coefficients are obtained and discussed for different values of the porous-effect parameter, the normalized distance between the barrier and the channel end-wall, and the length of submergence of barriers for all types of barrier configurations. The dynamic pressure distributions for various porous-effect parameters are analyzed for the three types of wavemakers. The wave amplitudes at large distances are obtained and analyzed for different values of the porous-effect parameter and the distance between the wavemaker and the channel end-wall. 相似文献
124.
K. L. Sahoo C. S. Sivaramakrishnan A. K. Chakrabarti 《Metallurgical and Materials Transactions A》2000,31(6):1599-1610
Studies of solidification behavior have been conducted on cast Al-Fe-V-Si alloys. The first phase to precipitate during solidification
of an Al-8.3Fe-0.8V-0.9Si alloy is Al3Fe(V,Si), which is isostructural with the Al3Fe phase. Thereafter, the solidification proceeds through several invariant reactions. The final invariant reaction is associated
with a pronounced arrest. The temperature of this arrest is a function of the cooling rate and modification treatment, with
magnesium added as an Al-20 pct Mg or Ni-20 pct Mg master alloy. The coarse iron aluminide precipitates in a slow-cooled (>1
°C/s) cast structure transform to a ten-armed, star-like morphology upon chill casting the melt (cooling rate >10 °C/s) from
900 °C or upon water quenching from above 800 °C. Treatment with magnesium refines the morphology, size, and distribution
of iron aluminide precipitates in slow-cooled alloys. 相似文献
125.
Baral SS Das N Ramulu TS Sahoo SK Das SN Chaudhury GR 《Journal of hazardous materials》2009,161(2-3):1427-1435
The present study evaluates the feasibility of using a thermally activated fresh water weed in removing Cr(VI) from wastewater through column studies. The effect of flow rate, bed height and Cr(VI) concentration of the feed solution on the adsorption capacity of the activated weed was investigated. The adsorption capacity increased with decrease in both flow rate and bed height but increased with an increase in initial adsorbate concentration. Four different kinetic models, such as. Adams-Bohart, Bed Depth Service Time (BDST), Thomas and Yoon-Nelson models were first applied to the experimental data to predict the breakthrough curve and to determine the characteristic parameters of the column useful for designing large-scale column studies. Different statistical methods such as Sum of the Square of the Error (SSE), Sum of the Absolute Error (SAE), Average Relative Error (ARE), Average Relative Standard Error (ARS) and regression coefficient, were applied to evaluate the prominent and unique characteristic features of the experimental and predicted parameters under the respective models to find out the best fit. The performance stability of the adsorbent was tested by continuous adsorption-desorption studies. 相似文献
126.
Gadadhar Sahoo 《Corrosion Science》2008,50(1):131-143
The corrosion behaviour of three phosphoric irons P1 (Fe-0.11P-0.028C), P2 (Fe-0.32P-0.026C) and P3 (Fe-0.49P-0.022C) has been studied in simulated concrete pore solution (saturated Ca(OH)2 solution) containing different chloride concentration. This has been compared with that of two commercial concrete reinforcement steels, a low carbon steel TN (Fe-0.148C-0.542Mn-0.128Si) and a microalloyed corrosion resistant steel CS (Fe-0.151C-0.088P-0.197Si-0.149Cr-0.417Cu). The beneficial aspect of phosphoric irons was revealed from potentiodynamic polarization experiments. The pitting potentials and pitting nucleation resistances for phosphoric irons and CS were higher than that for TN. Electrochemical impedance spectroscopy (EIS) studies revealed thickening and growth of passive film as a function of time in case of phosphoric irons and CS in saturated Ca(OH)2 pore solutions without chloride and in the same solution with 0.05% Cl− and 0.1% Cl−. In case of TN, breakdown of passive film resulted in active corrosion in simulated pore solution containing 0.1% Cl−. Linear polarization resistance measurements complemented EIS results. Visual observations indicated that phosphoric iron P3 was immune to corrosion even after 125 days of immersion in saturated Ca(OH)2 solution containing 5% NaCl. The good corrosion resistance of phosphoric irons in simulated concrete pore solution containing chloride ions has been related to the formation of phosphate, based on ultraviolet spectrophotometric analysis and Pourbaix diagram of phosphorus-water system. 相似文献
127.
Mohd. Kaleem Khan Ravi Kumar Pradeep K. Sahoo 《International Journal of Refrigeration》2009,32(2):261-271
The present experimental investigation has been carried out to investigate the effects of various geometric parameters on the mass flow rate of R-134a through diabatic spiral capillary tube. In diabatic flow, the capillary tube is bonded with the compressor suction-line to form a counter-flow exchanger. The lateral type of diabatic capillary tube has been investigated in the present experimental study. The major geometric parameters investigated are capillary tube diameter, capillary tube length and coil pitch. In addition, effect of inlet subcooling on the mass flow rate through diabatic spiral capillary tube is also done. A comparison of the performance of diabatic spiral capillary tube has been made with adiabatic spiral capillary tube. Generalized empirical correlation for diabatic spiral capillary tube has also been proposed. It has been found that the predictions of the proposed correlation lie in the error band of ±7%. 相似文献
128.
Havelock’s type of expansion theorems, for an integrable function having a single discontinuity point in the domain where it is defined, are utilized to derive analytical solutions for the radiation or scattering of oblique water waves by a fully extended porous barrier in both the cases of finite and infinite depths of water in two-layer fluid with constant densities. Also, complete analytical solutions are obtained for the boundary-value problems dealing with the generation or scattering of axi-symmetric water waves by a system of permeable and impermeable co-axial cylinders. Various results concerning the generation and reflection of the axisymmetric surface or interfacial waves are derived in terms of Bessel functions. The resonance conditions within the trapped region are obtained in various cases. Further, expansions for multipole-line-source oblique-wave potentials are derived for both the cases of finite and infinite depth depending on the existence of the source point in a two-layered fluid. 相似文献
129.
Manojit De Sugato Hajra Rashmi Tiwari Sushrisangita Sahoo R.N.P. Choudhary H.S. Tewari 《Ceramics International》2018,44(10):11792-11797
The paper mainly reports the effect of NaNbO3 (as a doping material) on the structural (crystal data and microstructure), dielectric (permittivity, dissipation of energy) and electrical (impedance, modulus, and conductivity) characteristics of BiFeO3 forming a solid solution of Bi.8Na.2Fe.8Nb.2O3. By analysis of the room temperature X-ray diffraction data, the formation of pure-phase material and its crystal data were obtained. The comprehensive studies of dielectric parameters (relative dielectric constant (εr), and tangent loss (tan δ) were measured in a wide range of temperature (25–450?°C) and frequency (1?kHz-1?MHz). The surface morphology, obtained with a gold-coated pellet sample, exhibits the high density of the sample. The frequency-temperature dependence of conductivity follows the Jonscher’s Universal Power law. The electrical behavior of the compound has been studied using complex impedance and modulus data. The effect of grain and grain boundary on the capacitive and resistive properties of the material has been studied from complex impedance spectroscopy. 相似文献
130.