http://nopr.niscpr.res.in/handle/123456789/61287 2026-10-12T00:31:20Z http://nopr.niscpr.res.in/handle/123456789/61302 Title: Entropy generation on chemically reactive hydromagnetic oscillating flow of third grade nanofluid in a porous channel with Cattaneo-Christov heat flux Authors: Reddy, A Subramanyam; Govindarajulu, K; Beg, O Anwar; Prasad, V Ramachandra Abstract: The heat and mass transfer characteristics along with Cattaneo-Christov heat flux on oscillating hydromagnetic flow of third grade nanofluid through a permeable channel under entropy generation analysis have been examined in this paper. The impacts of chemical reaction, Brownian motion, thermophoresis, Ohmic heating, and radiative heat have also been taken into consideration. The Buongiorno nanofluid model has been utilized for the present analysis.The investigation related to the present study is helpful in biomedical engineering, manufacturing industries as coolants, energy conservation, cancer treatments (like hyperthermia), dynamics of physiological fluids, biomedicines, and nano-drug suspension in pharmaceuticals. The system of nonlinear ordinary differential equations (ODEs) have been attained and solved by applying the Runge-Kutta 4th order method with the help of shooting process after the execution of the perturbation procedure on nondimensional partial differential equations (PDEs). The results of the present study have been deliberated by plotting graphs for the effects of various non-dimensional parameters on entropy, Bejan number, concentration, velocity, and temperature. The numerical values of heat and mass transfer rates for different physical parameters have been computed. Page(s): 9-22 2023-01-01T00:00:00Z http://nopr.niscpr.res.in/handle/123456789/61301 Title: Adsorption study on the removal of ciprofloxacin in aqueous solution by an acidic ion exchange resin with bifunctional group Authors: Jia, Bingqian; Zheng, Changlian; Chen, Bin; Li, Rong Abstract: Removal of fluoroquinolone antibiotic pollutants in the aquatic environment has become a research hotspot. In this work, two skeletal resins and four acidic ion exchange resins have been used as adsorbent materials to evaluate their adsorption properties for fluoroquinolone antibiotic ciprofloxacin (CIP) in aqueous solution. Compared with other materials, the sulfonic-phosphoric acid-based bifunctional resin S9570 has shown the best adsorption performance for CIP. The effect of solution pH on the adsorption of CIP by S9570 has been further explored, and the optimal adsorption capacity has been obtained at pH 4.0. The adsorption kinetics and thermodynamics of S9570 for CIP have been investigated in details. The high fits of the pseudo-second-order and intraparticle diffusion equations indicate that these two models can better describe the adsorption process of S9570 for CIP which has been jointly controlled by chemical adsorption and intraparticle diffusion steps and has been accompanied by weak or intermediate initial adsorption behaviour. The best fit results of Langmuir has indicated that there exists a monolayer adsorption on the surface of the S9570.Thermodynamic parameters suggest that the adsorption is an endothermic, spontaneous process with increased randomness at the solid-liquid interface. Through this evaluation of resin adsorption materials, it has been proved that the adsorbent material has good reusability and antiinterference performance. Page(s): 23-34 2023-01-01T00:00:00Z http://nopr.niscpr.res.in/handle/123456789/61300 Title: Experimental studies on combustion performance of beeswax-paraffin blended solid fuels in a hybrid rocket Authors: G, Saravanan; Shah, Adithy; Saha, Shawon Abstract: The study intends to investigate the physical, chemical and thermal characteristics of paraffin blended fuels to determine their suitability as a solid fuel in a hybrid rocket. Wax fuels are a viable and efficient alternative to conventional rocket fuels, having excellent structural strength and thermal and mechanical properties. By utilizing both axial and swirl injection technique, the combustion performance of paraffin – beeswax blended fuels have been tested with a fabricated cylindrical grain in a laboratory-scale rocket setting along with oxygen. The test outcomes revealed solid fuel compositions of more beeswax content in paraffin wax on an oxygenated gaseous environment with a swirl-flow injection method has the highest average regression rate of 1.649 mm/sec at 181 kg/m2s mass flux. Axially injected oxygen with pure paraffin wax has the lowest value of 0.85 mm/sec at 96 kg/m2s. The regression rate comparisons revealed that oxygen injection by a swirl injector increased the regression rates by 40% for mass fluxes greater than 80 kg/m2s. Compared to other studies, the combustion efficiencies have been obtained in this study are good. Blended fuels can manage and increase combustion efficiencies for axial and swirl flow conditions. Swirl injectors outperform axial injectors for oxygen injection and allow for a higher proportion of Beeswax combined with paraffin. This study exclusively designed and manufactured an axial injector and swirl injector, according to the required dimensions of a lab-scale hybrid rocket's combustion chamber, injector, and exhaust nozzle, and their performances have been evaluated. Page(s): 35-45 2023-01-01T00:00:00Z http://nopr.niscpr.res.in/handle/123456789/61299 Title: Impact of titania phase structure and surface reactivity on the photocatalytic degradation of various dyes and textile wastewater Authors: Yurtsever, Hüsnü Arda; İloğlu, Onur; Çiftçioğlu, Muhsin Abstract: Titania (TiO2) powders have been prepared by precipitation method in different precipitation media which contain sulfate, nitrate or organic species. Photocatalytic degradation of different dyes and a real textile wastewater have been conducted with these powders along with commercial powder Degussa P25 for comparison. Ethyl alcohol (organic medium), sulfuric acid (sulfate medium) and nitric acid (nitrate medium) have been used to dissolve titanium precursor for the precipitation of TiO2 in ammonia solution. UV-Vis DRS and XPS results indicate that S doping in sulfate medium precipitated powder and N doping in nitrate medium precipitated powder has been occurred and the presence of S or N containing impurities on the grain boundaries have been improved light absorption of TiO2 significantly. However, these powders have exhibited low surface reactivities. The highest surface reactivity has been obtained with the powder precipitated in organic medium which also has the highest crystallite sizes (76 nm rutile and 34 nm anatase crystallites) with relatively low rutile weight percentage (10.0%). The surface-normalized rate constants of this powder are 0.02038 min-1.m-2 in real textile wastewater degradation and 0.0161 min-1.m-2 in methyl orange degradation, which are 0.01563 and 0.0091 min-1.m-2, respectively, for Degussa P25. Results have shown that this powder show 30-70% higher surface reactivities compared to Degussa P25. The main structural difference of organic medium precipitated powder and Degussa P25 has been found to be the anatase-rutile weight ratio and crystallite size of rutile phase whereas band gap energy of Degussa P25 is lower and other properties are not significantly different. Page(s): 46-56 2023-01-01T00:00:00Z