Photocatalytic degradation of synthetic dye by immobilised doped nanoparticles on polyurethane foam reactor using RSM

T. Usharani,R. Baskar,B. Palanisamy 한양대학교 세라믹연구소 2020 Journal of Ceramic Processing Research Vol.21 No.5

The aim of this work is to optimize the functional factors that influence the efficiency of the photodegradation of methyleneblue using SiO2–TiO2 nanoparticles on polyurethane foam reactor by UV-TiO2 photocatalytic process. The experimentalfactors like dye concentration, pH value, temperature, reaction time are analyzed by RSM (Response Surface Methodology)to achieve the efficacy of the best textile dye decomposition. The effect of operational factors to check the photodegradationefficiency of the methylene blue (MB) for SiO2 nanoparticles and SiO2-TiO2 nanoparticles are examined by response surfacemethodology and contour plots. The degradation percentage of MB by SiO2 and SiO2-TiO2 nanoparticles are 40.32% and67.01% respectively. The best values of MB decomposition is achieved by SiO2-TiO2 with 10 ppm initial dye concentration, pH6.88, temperature of 32 oC and 480 min reaction time. The satisfactory results is obtained through the correlation of theexperimental values and predicted data by regression analysis (R2 = 0.9984).

Growth and characterization of neodymium and ytterbium doped barium chloride dihydrate single crystals

Kalidasan M.,Baskar K.,Dhanasekaran R. 한국물리학회 2016 Current Applied Physics Vol.16 No.9

Pure, Nd doped and Nd:Yb co-doped barium chloride dihydrate (BaCl2$2H2O) single crystals were grown and analyzed with various characterization techniques. The measured unit cell parameters show that the grown crystals belong to monoclinic system. Powder X-ray diffraction spectra indicates that the dopants enhance (2 1 0) orientation of BaCl2$2H2O crystal. X-ray rocking curves have been recorded to analyze the crystallinity of the grown single crystals. Optical absorption spectra of the grown crystals contain strong absorption bands in infrared region. Spectral overlap of absorption bands of Yb3þ and Nd3þ ion around 850 nme1060 nm in Nd:Yb co-doped single crystal indicates the prospect of energy transfer between them. A significant enhancement has been observed in the photoluminescence spectrum of Nd:Yb codoped single crystal recorded with 244 nm laser excitation. Photon upconversion ability of the crystals was tested using Nd:YAG laser of wavelength 1064 nm. An unusual upconverted green emission from pure centrosymmetric BaCl2$2H2O single crystal has been observed. The energy of upconverted green light of Nd:Yb co-doped barium chloride dihydrate single crystal is higher which may be due to energy transfer occurred between Yb3þ and Nd3þ ions. FTIR and FT-Raman spectral analyses were carried out to study the vibrational modes of pure, Nd doped and Nd:Yb co-doped BaCl2$2H2O single crystals.

Adsorption of basic red 9 on activated waste Gossypium hirsutum seeds: Process modeling, analysis and optimization using statistical design

N. Sivarajasekar,R. Baskar 한국공업화학회 2014 Journal of Industrial and Engineering Chemistry Vol.20 No.5

Sulfuric acid activated immature Gossypium hirsutum seed was utilized as adsorbent for the batch adsorption of basic red 9. The main and interactive effects of five process factors like, adsorbent dose, initial dye concentration, contact time, pH and temperature were investigated to select the influencing key factors via 25 two-level full factorial design. Box–Behnken statistical design with the selected key factors employed for process optimization. The simultaneous optimization by Derringer’s desirability function indicated that 54.27% removal of BR9 could be possible at the optimal conditions. Isotherm and kinetic studies confirmed the chemisorption on homogeneous and heterogeneous patches. 2013 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V.

Performance of Self-Compacting Concrete Containing Different Mineral Admixtures

P. Ramanathan,I. Baskar,P. Muthupriya,R. Venkatasubramani 대한토목학회 2013 KSCE JOURNAL OF CIVIL ENGINEERING Vol.17 No.2

Self-Compacting Concrete is an innovative concrete that does not require vibration for placing and compaction. It is able to flow under its own weight, completely filling formwork and achieving full compaction, even in the presence of congested reinforcement. One of the disadvantages of self-compacting concrete is its cost, associated with the use of high volumes of Portland cement and use of chemical admixtures. One alternative to reduce the cost of self-compacting concrete is the use of mineral admixtures such as silica fume, ground granulated blast furnace slag and fly ash, which is finely, divided materials added to concrete during mixture procedure. When these mineral admixtures replace a part of the Portland cement, the cost of self-compacting concrete will be reduced especially if the mineral admixtures are waste or industrial by-product. Moreover, the use of mineral admixtures in the production of selfcompacting concrete not only provides economical benefits but also reduces heat of hydration. The incorporation of mineral admixtures also eliminates the need for viscosity-enhancing chemical admixtures. The lower water content of the concrete leads to higher durability, in addition to better mechanical integrity of the structure. This paper presents an experimental investigation on strength aspects like compressive, flexural and split tensile strength of self compacting concrete containing different mineral admixtures and workability tests for different mineral admixtures (slump, L-box, U-box and T50) are carried out. The methodology adopted is that mineral admixtures are replaced by 30%, 40% and 50% for Portland cement and performance is measured and compared. The influence of mineral admixtures on the workability, compressive strength, splitting tensile strength and flexural strength of self-compacting concrete was investigated. The mix proportion is obtained as per the guidelines given by European Federation of producers and contractors of special products for structure. The following inferences were made; optimum dosage of super plasticizer enhanced the flow property of the concrete. As a result, overall improvements in the flow and filling ability of the self-compacting concrete were observed. It is observed that when mineral admixtures used in self-compacting concrete, can reduce the amount of super- plasticizer necessary to achieve a given fluidity. It should be noted that the effect of mineral admixtures on admixture requirements is significantly dependent on their particle size distribution as well as particle shape and surface characteristics. From this view point, a cost effective self-compacting concrete design can be obtained by incorporating reasonable amounts of silica fume, fly ash, and ground granulated blast furnace slag.

Hydrothermal synthesis of chalcopyrite CuInS2, CuInSe2 and CuInTe2 nanocubes and their characterization

S. Sugan,K. Baskar,R. Dhanasekaran 한국물리학회 2014 Current Applied Physics Vol.14 No.11

CuInS2, CuInSe2 and CuInTe2 nanocubes of chalcopyrite structure have been successfully synthesized by hydrothermal process using deionized water as solvent at 180 C for 20 h. The crystallinity, compositional, morphological and optical properties of the synthesized samples were studied by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive X-ray (EDX), Raman and photoluminescence (PL) spectra analyses. The Raman spectra of the synthesized CuInS2, CuInSe2 and CuInTe2 samples show the dominant A1 modes at 293, 172 and 121 cm1 respectively. The possible chemical reaction and mechanism of nanocubes formation were discussed. The emission wavelength of as synthesized CuInS2, CuInSe2 and CuInTe2 samples were blue shifted at 746 nm (1.66 eV), 863 nm (1.43 eV) and 859 nm (1.44 eV) respectively.

Experimental investigation of vibrational isolation of automobile seat with various rubber materials

V. Pugazhenthi,S. Baskar,R. Rajappan 한양대학교 청정에너지연구소 2023 Journal of Ceramic Processing Research Vol.24 No.5

This research proposes a technique to reduce vibration transmission in vehicle seats by employing Silicon rubber andNeoprene rubber sheets of varying thicknesses between the seat base and seat mount. The aim is to optimize the acceptablevibration level and enhance vibration isolation. The study incorporates the latest advancements in the field of vibrationtransmission and the vibration properties of car seats. Various rubber sheets, including 3 mm and 4 mm of neoprene rubber,as well as 3 mm and 4 mm of silicone rubber, are mounted between the seat mount and seat base to act as a vibrating table. The research also examines current sensor technologies used to measure the transmission of vibrations from the car's base tothe seat. Experimental investigations reveal that using a 4 mm Neoprene rubber sheet on the seat base minimizestransmissibility, resulting in an identified RMS Acceleration of 0.014889 km/s2, RMS Velocity of 6.62675 cm/s, andDisplacement of 1.0625 mm. By considering the progress in new findings and the introduction of novel technologies, thisresearch explores the future research directions in this field.

Optimization, Production, and Partial Characterization of an Alkalophilic Amylase Produced by Sponge Associated Marine Bacterium Halobacterium salinarum MMD047

S. Shanmughapriya,G. Seghal Kiran,R. Gandhimathi,T. Bastin Baskar,Aseer Manilal,S. Sujith,Joseph Selvin 한국생물공학회 2009 Biotechnology and Bioprocess Engineering Vol.14 No.1

An endosymbiont Halobacterium salinarum MMD047, which could produce high yields of amylase, was isolated from marine sponge Fasciospongia cavernosa, collected from the peninsular coast of India. Maximum production of enzyme was obtained in minimal medium supplemented with 1% sucrose. The enzyme was found to be produced constitutively even in the absence of starch. The optimum temperature and pH for the enzyme production was 40℃ and 8.0, respectively. The enzyme exhibited maximum activity in pH range of 6~10 with an optimum pH of 9.0. The enzyme was stable at 40℃ and the enzyme activity decreased dramatically above 50℃. Based on the present findings, the enzyme was characterized as relatively heat sensitive and alkalophilic amylase which can be developed for extensive industrial applications.