http://nopr.niscpr.res.in/handle/123456789/59927 2026-10-10T02:13:59Z http://nopr.niscpr.res.in/handle/123456789/59939 Title: Synthesis of magnetic activated carbon from Citrus hystrix (Kaffir lime or Kolumichai) leaves with excellent Pb(II) adsorption performance towards electroplating wastewater Authors: Sribharathi, Swaminathan; Kavitha, Gurusamy; Sudha, Ramasamy Abstract: The adsorption behaviour of Pb(II) ions from aqueous solution has been successfully tested by magnetic activated carbon prepared from novel adsorbent such as Citrus hystrix leaves (MCHLAC) by co-precipitation method and followed by thermal activation. The optimum contact time for the removal Pb(II) ions onto MCHLAC is found to be 90 min, and the optimum pH ranged from 5.0–7.0 respectively. The functionality, surface morphology and elemental composition of MCHLAC have been explored by FTIR, SEM and EDX analysis. The equilibrium data agree well with Langmuir model, which confirm the monolayer coverage of Pb(II) ions onto MCHLAC and the maximum monolayer adsorption capacity is 345.65 mg g-1. The kinetic data follow by pseudo-second order model with film diffusion process. Thermodynamic studies indicate that the process of uptake of lead(II) ions is spontaneous and exothermic. A single –stage batch adsorber is designed using the Langmuir adsorption isotherm equation. The regeneration study show that MCHLAC could be effectively utilized for the removal of Pb(II) ions for seven cycles of operation. Page(s): 229-239 2022-05-01T00:00:00Z http://nopr.niscpr.res.in/handle/123456789/59938 Title: Manufacturing of chitosan based drug release systems from tamarind shells for long-term and effective methylprednisolone sodium succinate release Authors: Açarı, İdil Karaca Abstract: In this study a microparticular drug delivery system containing tamarind shell and chitosan has been developed to realize the controlled release of methylprednisolone sodium succinate an important corticosteroid. Drug-loaded tamarind shells are coated with chitosan for a pH-controlled release. The release kinetics of the system have been examined in detail at three different pH ranges (3, 5 and 7.4). In our pH sensitive release systems a slow release up to 39.02%±0.81 at pH=7.4 at 72 hours. But we see that there is a faster release at 70.58±1.73% at pH=5 and 96.68±1.70% at pH=3 in 72 hours. Rapid release in acidic media depends on the solubility of the chitosan structure in acidic environments. It is believed that the pH sensitive carrier system obtained within the scope of the study will have a high potential for use in many biomedical application areas (wound surface application, etc.). Page(s): 240-250 2022-05-01T00:00:00Z http://nopr.niscpr.res.in/handle/123456789/59937 Title: Removal of Erythrosine B using Prosopisspicigera L. wood carbon-iron oxide composite Authors: Ramalakshmi, R Dhana; Murugan, M; Jeyabal, V Abstract: The present study investigates the removal of Erythrosine B (EB), a neurotoxin and carcinogenic dye from aqueous system using Prosopisspicigera L. wood (PsLw) carbon-iron oxide composite. The adsorbent is well characterized by Fourier Transform Infra Red spectroscopy (FTIR), Scanning Electron Microscope (SEM) for surface morphology, Brunauer-Emmett-Teller nitrogen adsorption method (BET)/methylene blue method for surface area determination and potentiometric methods for surface charge (pHzpc) determination. The removal capacity of the adsorbent has been evaluated by batch method under varying pH, contact time, adsorbate initial concentrations, and in the presence of other ions. The Langmuir maximum adsorption capacity is found to be 487.8 mg/g at pH = 2.0 for an initial concentration of 250 mg/L. The adsorption follows pseudo second order kinetics and fits to Langmuir isotherm. The adsorption is thermodynamically spontaneous and exothermic in nature. Pore diffusion and mass transfer studies are performed. Column mode analysis is applied in the process for industrial applications. Page(s): 251-260 2022-05-01T00:00:00Z http://nopr.niscpr.res.in/handle/123456789/59936 Title: Organic additives based alkaline alumina slurry for selective removal of barrier layer metals Authors: Shukla, Arpita; Selvam, Noyel Victoria; Ramachandran, Manivannan Abstract: In the present work, tantalum (Ta) and copper (Cu) chemical mechanical polishing (CMP) has been carried out using a polishing slurry containing 2 wt% alumina (abrasive), 1 wt% potassium carbonate (oxidizer), and 0.25 wt% each urea and citric acid (additives). The Cu removal rate (RR) decreases with an increase in pH and is found to be minimum at pH 11 while Ta RR increases till neutral pH and then decreases till pH 11 having maximum RR at pH 7. Ta to Cu removal rate selectivity of 1:1.02 is attained at pH 11. Other parameters such as the effect of additives concentration, applied pressure, and platen rotational speed are also studied and results are reported to get a clear scenario. Surface charge analysis reveals that with change in pH, zeta potential alters and 30mV zeta potential is found at pH 11 which confirms the stability of the formulated slurry. To comprehend the removal mechanism of the metals, potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) are employed. The same trend is encountered for both corrosion current density (Icorr) and film resistance (Rfilm)values resulting from Tafel and EIS. Based on the research conducted a plausible material removal mechanism is suggested. Page(s): 261-269 2022-05-01T00:00:00Z