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101.
Sirajudeen A. Balasubramaniam Anuradha Karthikeyan S. 《Multimedia Tools and Applications》2022,81(27):38485-38512
Multimedia Tools and Applications - Cataract is considered as one of the foremost causes of blindness, especially among older people. In India, by the age 80, nearly half of older population either... 相似文献
102.
James K. Immanuvel Arokia Prabakaran R. Karthikeyan A. Prianka R. R. 《Wireless Networks》2022,28(8):3653-3663
Wireless Networks - To make the network more reliable and to address energy imbalance issues the cooperative selection of dynamic relay beamforming and energy balanced operation is proposed.... 相似文献
103.
This study aims at improving greywater reuse potential. An advanced physical filtration system named as GAC-MI-ME was developed to attain multi-grade effluents for versatile reuse of greywater. It consists of a matrix of treatment trains including coarse filtration, microfiltration, activated carbon, ultrafiltration, ultraviolet, and reverse osmosis. A preliminary set of experiments were conducted to characterize the greywater originating from shower, washbasin, and laundry. The samples were subsequently treated through GAC-MI-ME system. It was observed that the activated carbon along with microfiltration and coarse filtration played vital roles as pre-filtration for ultrafiltration and reverse osmosis. The contaminant load distributions of GAC-MI-ME system were observed with an average of 90.4% turbidity and 53.2% of biochemical oxidation demand (BOD5) as the pre-filtration, whereas the effluents at ultrafiltration and reverse osmosis showed unrestricted water reuse possibilities. The GAC-MI-ME system can be envisioned as advancement to the conventionally applied greywater treatments. 相似文献
104.
This paper exhibits the synthesis of a cardanol-based polymeric resin (CR) from cashew nut shell liquid as a composite matrix along with coconut shell (CS) as reinforcement utilizing poly-condensation technique. In the proposed method, the provincially gathered CSs are dried in an oven in order to expel dampness content. With an average diameter ranging from 25 to 75 µm, the dried CSs are then grated into small particles and in the compression molding method these particles are made into two sets for untreated and treated (5% NaOH) biocomposites with varying concentration of 0%, 10%, 20%, 30%, and 40%. The thermal properties are assessed by thermo gravimetric analysis (TGA) and differential thermal analysis (DTA) whereas the chemical formulation is reckoned by the assistance of Fourier transforms infrared spectroscopy. The microstructures of the composites are portrayed by scanning electron microscopy to scrutinize the morphological and surface characteristics of CR and CS. The TGA and DTA results revealed that the treated CS particle at 25 and 75 µm thermal stability (484° and 459°) with untreated CS particle (466°C and 449°C) at 30% particle loading condition. The 25-µm CS particles are thermally more stable than 75 µm particles. Veritably it is unveiled that, a polymeric matrix composite combined with untreated and treated CS particles might be a good alternative remembering the ultimate goal to nab an eco-friendly product. 相似文献
105.
Lee Hwangjae Thirunavukkarasu Guru Karthikeyan Kim Semin Lee Jae Young 《Nano Research》2018,11(11):5997-6009
Nano Research - In situ hydrogelation systems, such as transdermal polymerization, allow for external control over the gelation processes in a minimally invasive way. Recently, a novel system... 相似文献
106.
S Arun Kumar P Suresh Mohan Kumar Ravishankar Sathyamurthy A. Muthu Manokar 《亚洲传热研究》2020,49(1):103-119
Sun radiation is the heat energy source for solar still. That should be utilized maximum for increasing the evaporative rate at the top surface of the brine. The pyramid shape solar still (PSSS) can receive solar input radiation from all four directions. In this research, the top layer of conventional pyramid shape solar still (CPSSS) is covered with air‐packed cover and analysed the effect in the modified still after air packed in between the two glasses, finally, that result is compared with the CPSSS. The air inside the two glasses will be receiving maximum radiation and retain in it. It can be used as top side insulation and which can ensure the maximum insulation for heat energy inside the PSSS. The CPSSS and air‐packed pyramid shape solar still (APPSSS) were fabricated and experimented. The experiments were conducted at an ambient condition of the Chennai, Tamil Nadu (12.9416°N, 80.2362°E). The CPSSS gives good yield at evening when an increase in wind velocity. The APPSSS gives a lower performance as compared to the CPSSS due to the air‐packed cover. 相似文献
107.
A. Muthu Manokar M. Vimala D. Prince Winston D. R. Rajendran Ravishankar Sathyamurthy A. E. Kabeel 《亚洲传热研究》2020,49(6):3651-3662
In this paper, a year around energy efficiency (EnE) and economic analysis of single slope solar still (SSSS), the single slope solar still with glass cooling (SSSSGC), the single slope solar still with basin heating (SSSSBH), and the single slope solar still with glass cooling and basin heating (SSSSGCBH) was carried out based on the distilled water production. The annual yield production from the SSSS, SSSSGC, SSSSBH, and SSSSGCBH were 476.16, 637.44, 970.24, and 1167.36 kg, respectively. The yearly yield produced from the SSSSBH and SSSSGCBH was increased by 50.92% and 59.21%, respectively, as compared with the SSSS. Moreover, the annual EnE of the SSSSGCBH was 28.75%. However, the EnE of the SSSS was 11.73%. Also, freshwater making cost is found to be 18.9, 24.9, 37.9, and 45.6 Rs/day for the SSSS, SSSSGC, SSSSBH, and SSSSGCBH, respectively, if the buying cost of freshwater is Rs 10. 相似文献
108.
Karthikeyan Ramachandran Zuccarini Carmine Katsumi Yoshida Toru Tsunoura Doni Daniel Jayaseelan 《Journal of the European Ceramic Society》2021,41(9):4761-4773
Commercially available Ti3SiC2 and Ti2AlC ceramics were used in this study to investigate their wet corrosion and mechanical behaviour as they were under investigation for years for their applications in the field of nuclear as cladding materials and aerospace. The test coupons of dimension 3 × 4 × 40 mm3 and 3 × 4 × 20 mm3 were machined out from commercially available samples for the 3-pt bend test and wet corrosion test, respectively. The water vapour corrosion studies of these samples were carried out at 800 ℃, 1000 ℃, 1200 ℃ for 10, 20 and 100 h in gas flow condition containing 50 % steam + 50 % air. Phase analysis of the as-received Ti3SiC2 and Ti2AlC ceramics revealed the presence of other impurity phases such as TiC and TiSi2. The XRD patterns of the oxidised samples show the formation of rutile as the major phase in both materials. The oxidation layer formed on Ti3SiC2 sample was measured to be 280 μm after exposing the sample in steam for 100 h at 1200 °C. The water vapour corrosion studies reveal that Ti2AlC has high oxidation resistance compared with the Ti3SiC2 due to the formation of protective layers of TiO2 and Al2O3 which resulted in reduced weight gain and oxidation layer thickness. Three-point bend tests were conducted at room temperature for the samples after the water vapour corrosion test at 1000 °C/100 h. The TAC samples showed no degradation in the bending strength (244 MPa) whereas the TSC samples showed reduced strength of 320 MPa. The tensile strength of the samples was measured at room temperature and hydrothermal condition (250 °C and 250 bars pressure) and it was observed that Ti3SiC2 had high tensile strength (190 MPa) in hydrothermal conditions. The tensile strength results were validated using Finite element analysis (FEA) using ANSYS and the FEA results showed a negligible variance of 7 % compared with experimental method. Mathematical modelling based on one dimensional solution of diffusion equation combined with Deal-Grove model was employed to study and compare the oxidation thickness for the linear and parabolic models for the ceramics. The model was effective in validating the oxidation thickness of Ti3SiC2 showing that the experimental thickness was closer to that of mathematical model. 相似文献
109.
110.
Investigation of Raman Modes and Born‐Effective Charges in AgNb1/2Ta1/2O3: A Density‐Functional and Raman Scattering Study 下载免费PDF全文
Kotagiri Ganga Prasad Manish K. Niranjan Saket Asthana R. Karthikeyan 《Journal of the American Ceramic Society》2016,99(1):332-339
Using ab initio density‐functional theory, the Born‐effective charge tensors and zone‐center phonon mode frequencies are computed for AgNb1/2Ta1/2O3 in monoclinic P2/m and orthorombic Pbcm symmetries. The experimental mode frequencies are obtained from deconvolution of Raman spectrum of prepared AgNb1/2Ta1/2O3 samples and are compared with computed mode frequencies. The Raman modes with high (>350 cm?1) and low frequencies (<90 cm?1) correspond to Ag and O vibrations, respectively. The modes in intermediate frequency band (120–350 cm?1) are dominated by Nb(Ta)–O vibrations. The computed effective charge tensors of cations at A (Ag) and B (Nb, Ta) sites are found to be diagonal. The off‐diagonal components of charge tensor are found sizeable only for O ions in orthorhombic AgNb1/2Ta1/2O3 with Pbcm symmetry. Further, charge tensor structure of O ions is found to depend on site symmetry in the unit cell. Charge tensor components for Nb, Ta, and O ions differ significantly from their nominal ionic values suggesting (1) large local dipole moments induced by off‐centering of Nb(Ta) ions and tilting(rotations) of Nb(Ta)O6 octahedra, (2) hybridization between d‐orbitals of Nb(Ta) and p‐orbitals of O atoms. Furthermore, the electronic structure, directional dependence of effective charges and performance of LDA (GGA) exchange‐correlation functionals with regard to computed values are also discussed. 相似文献