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Item Preparation, characterization and performance study of poly(isobutylene- alt-maleic anhydride) [PIAM] and polysulfone [PSf] composite membranes before and after alkali treatment(2011) Padaki, M.; Isloor, A.M.; Belavadi, G.; Prabhu, K.N.Recently, nanofiltration (NF) membranes have been drawing much attention in the field of filtration and the purification process of water/industrial effluents, because of their energy efficiency and low cost. Although reverse osmosis (RO) membranes are widely used in present desalination units, NF membranes are considered as "future membranes" for desalination, because of the low operating pressure. In the present paper, we hereby report the synthesis of a new composite NF membranes of poly(isobutylene-alt-maleic anhydride) (PIAM) with polysulfone, using a diffusion-induced phase separation (DIPS) method. The anhydride groups were converted to acid group by alkaline treatment. Newly prepared composite membranes were characterized by Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), and differential scanning calorimetry (DSC) studies. The membranes were tested for salt rejection and water swelling. The resulted NF membranes exhibited significantly enhanced water permeability while retaining high salt rejection. The flux and rejection rate of the NF membrane to Na2SO4 (500 ppm) reached to 11.73 L/(m2 h) and 49% rejection under 1 MPa and also 70:30 composition of the membrane showed 54% water swelling; contact angle measurement, ion exchange capacity, and water uptake of the membrane were recorded. © 2011 American Chemical Society.Item A review on RO membrane technology: Developments and challenges(Elsevier B.V., 2015) Shenvi, S.S.; Isloor, A.M.; A.F., A.F.Reverse osmosis (RO) based desalination is one of the most important and widely recognized technologies for production of fresh water from saline water. Since its conception and initiation, a significant development has been witnessed in this technology w.r.t. materials, synthesis techniques, modification and modules over the last few decades. The working of a RO plant inclusive of the pretreatment and post-treatment procedures has been briefly discussed in the article. The main objective of this review is to highlight the historical milestones achieved in RO technology in terms of membrane performance, the developments seen over the last few years and the challenges perceived. The material properties of the membrane dominate the performance of a RO process. The emergence of nano-technology and biomimetic RO membranes as the futuristic tools is capable of revolutionizing the entire RO process. Hence the development of nano-structured membranes involving thin film nano-composite membranes, carbon-nanotube membranes and aquaporin-based membranes has been focussed in detail. The problems associated with a RO process such as scaling, brine disposal and boron removal are briefed and the measures adopted to address the same have been discussed. © 2014 Elsevier B.V.Item Carbon nanotube- and graphene-based advanced membrane materials for desalination(Springer Verlag, 2017) Hebbar, R.S.; Isloor, A.M.; Siddique, I.; Asiri, A.M.The development of membrane-based desalination and water purification technologies offers new alternatives to meet the global freshwater demand. Rapid advancement in carbon nanotube-based and graphene-based nanomaterials has drawn the attention of scientific investigators on various desalination technologies. These nanomaterials indeed offer advantageous structure, size, shape, porosity and mass transport behavior for membrane separation process. This article reviews theoretical and experimental investigations of carbon nanotube- and graphene-based composite materials for desalination. Special attention is given to the simulation of molecular transport through these materials. Further, recent advances in the application of functionalization of carbon nanotube- and graphene-based materials for salt rejection and hydraulic permeation properties are discussed. © 2017, Springer International Publishing AG.Item A comprehensive review on evaporative cooling systems(Elsevier B.V., 2023) Kapilan, N.; Isloor, A.M.; Karinka, S.The evaporative cooling system (ECS) is one of the cheapest and oldest cooling technologies. The conventional single stage ECS is most widely used in domestic application, particularly in hot and dry regions. However, in this system, the temperature of the air cannot be reduced below the wet bulb temperature of the air. The multistage ECS system helps to overcome this problem. The combination of direct and indirect ECS helps to reduce the temperature of the air below its wet bulb temperature. The further reduction in air temperature may be achieved with the help of the cooling coil driven by vapour compression system. The energy consumed by the ECS is lower as compared to vapour compression refrigeration system. The ECS can be driven with the help of solar power. The conventional cooling pad used in ECS can be replaced with locally available natural fibers to reduce initial cost and to reduce dependence on import of cooling pads. The performance of the ECS can be improved with the help of heat pipe. Various techniques are used to enhance ECS's performance. The performance of the vapour compression refrigeration system can be improved with the help of ECS. This paper discusses basics and types of ECS, methods used to increase the performance of ECS, types of natural fiber cooling pad material, process variables affecting ECS, recent technical advancements, challenges and opportunities. © 2023 The AuthorsItem The inhibition action of ethyl-2-phenyl hydrozono-3-oxobutyrate on the corrosion of 6061 Al alloy/SiCp composite in hydrochloric acid medium(Sociedad Chilena de Quimica, 2010) Kini U, U.A.; Shetty, P.; Shetty, S.D.; Isloor, A.M.; Herle, R.The inhibition behavior of ethyl-2-phenyl hydrozono-3-oxobutyrate on the corrosion of 6061 Al alloy/SiCp composite in 0.1, 0.5 and 1 N hydrochloric acid solution at four different temperatures (30-60 °C) has been investigated using potentiostatic polarization techniques and weight loss method. The results indicated that the corrosion inhibition efficiency and the extent of surface coverage were increased with the increase in inhibitor concentration up to a critical concentration. The adsorption of the inhibitor compound on the composite surface was found to obey Temkins' and Langmuir adsorption isotherms. The potentiostatic polarization results have revealed that oxobutyrate acts as an efficient cathodic inhibitor for the corrosion of 6061 Al alloy/SiCp composite in HCl medium. The thermodynamic parameters for the corrosion and adsorption processes were determined. © 2010.Item Synthesis, characterization & impedance studies of some new nano filtration membranes(Trans Tech Publications Ltd ttp@transtec.ch, 2010) Padaki, M.; Hegde, C.; Isloor, A.M.In the recent years membrane technology has gained significant attention from polymer chemists all around the world due to their attractive features such as efficiency, low costs, low energy costs and as effective solutions to longstanding problems in the chemical industries. Membrane technologies have been widely applied in the separation of liquids and even gases. Many separation problems can be solved economically by nanofiltration alone or in combination with other separation processes. This study aimed to synthesize polysulfone based nanofiltration membranes using DIPS (diffusion induced phase separation) technique. Newly synthesized polymer membranes were subjected to Infra red spectral and water uptake studies. Membranes were also characterized using electrochemical spectroscopy for their proton conducting property. Their surface morphology is visualized by SEM. © (2010) Trans Tech Publications.Item 2-Phenoxy-acetohydrazide(2010) Fun, H.-K.; Ching Kheng, C.K.; Isloor, A.M.; Dhanya, D.; Shetty, P.In the title compound, C8H10N2O 2, the acetohydrazide group is almost planar, with an r.m.s. deviation of 0.028 Å. In the crystal, the mol-ecules are linked by inter-molecular C-H?O, N-H?O and N-H?N hydrogen bonds into infinite sheets lying parallel to (001). The acetohydrazide O atom accepts two N-H?O links and one C-H?O link.Item 6-(4-Bromo-phenyl)-2-ethoxy-4-(4-ethoxyphenyl)nicotinonitrile(2010) Chantrapromma, S.; Fun, H.-K.; Suwunwong, T.; Padaki, M.; Isloor, A.M.The mol-ecule of the title nicotinonitrile derivative, C22H 19BrN2O2, is non-planar, the central pyridine ring making dihedral angles of 7.34 (14) and 43.56 (15)° with the 4-bromophenyl and 4-ethoxyphenyl rings, respectively. The ethoxy group of the 4-ethoxyphenyl is slightly twisted from the attached benzene ring [C-O-C-C = 174.2 (3)°], whereas the ethoxy group attached to the pyridine ring is in a (+)syn-clinal conformation [C-O-C-C = 83.0 (3)°]. A weak intra-molecular C-H?N inter-action generates an S(5) ring motif. In the crystal structure, the mol-ecules are linked by weak inter-molecular C-H?N inter-actions into screw chains along the b axis. These chains stacked along the a axis. ?-? inter-actions with centroid-centroid distances of 3.8724 (16) and 3.8727 (16) Å are also observed.Item Synthesis, characterization and biological activities of some new benzo[b]thiophene derivatives(2010) Isloor, A.M.; Kalluraya, B.; Pai, K.Benzo[b]thiophene molecules are found to be important tools in synthetic medicinal chemistry. They are of current interest due to their wide spectrum of pharmacological properties. In view of the biological activities of benzo[b]thiophene containing molecules, in this present research work, we propose the synthesis of some new benzo[b]thiophene derivatives such as thiadiazoles, oxadiazoles, pyrazolin & diaryl pyrazoles starting from 3-chlorobenzo[b]thiophene-2-carboxyl chloride. These newly synthesized compounds were characterized by elemental analyses, I.R, NMR and Mass spectral studies. Some of the selected compounds were screened for their antibacterial, antifungal and anti-inflammatory studies. Many of the molecules were found to be potent. © 2009 Elsevier Masson SAS. All rights reserved.Item 2-(2-Chloro-phenoxy)acetohydrazide(2010) Fun, H.-K.; Ching Kheng, C.K.; Isloor, A.M.; Dhanya, D.; Shetty, P.In the title compound, C8H9ClN2O 2, the acetohydrazide group is approximately planar, with the maximum deviation of 0.031 (2) Å. In the crystal, the mol-ecules are linked by N-H?N, N-H?O and C-H?O hydrogen bonds, with the acetohydrazide O atom accepting two C-H?O links and one N-H?O link. This results in infinite sheets lying parallel to (100).