Utilization of additives in biodiesel blends for improving the diesel engine performance and minimizing emissions through a modified Taguchi approach.

Biodiesel from Jatropha oil is produced through catalyzed homogeneous transesterification. Hydrogen peroxide (H2O2) is considered as additive. Blends of Jatropha considered in the present study are 60% diesel, (40-A)% biodiesel and A% additive, varying A from 0 to 10. Identifying optimal input variables (such as additive volume percentage, injection pressure, and load) is important for improving the engine performance and reducing emissions. Air-fuel ratio; brake specific fuel consumption (BSFC); and brake thermal efficiency (BTE) are the engine performance characteristics. Carbon monoxide (CO); carbon dioxide (CO2); exhaust gas temperature (EGT); nitrogen oxide (NOx); and smoke opacity are the emission characteristics. 27 experiments need to be performed for the assigned 3 levels and 3 input variables. The Taguchi's L9 orthogonal array (OA) is chosen to perform only 9 experiments to obtain the optimal solution. The expected range of performance characteristics and emissions was obtained following a modified Taguchi approach. Empirical relationships are developed and verified through engine performance and emission characteristics.

Investigation of the nuclear radiation interaction parameters of selected polymers for radiation therapy and dosimetry.

The mass attenuation coefficient (MAC), effective atomic number (Zeff), equivalent atomic number (Zeq), fast neutron removal cross-section (FNRCS), energy absorption buildup factor (EABF), mass-energy absorption coefficient (MenAC), relative kerma, and computed tomography (CT) numbers were calculated for the alginates, bisphenol A-glycidyl methacrylate (Bis-GMA), chitin, hyaluronic acid, polycaprolactone (PCL), polyether ether ketone (PEEK), polyethylene glycol (PEG), polyglycolide (PGA), polylactic acid (PLA), poly lacto-co-glycolic acid (PLGA), poly methyl methacrylate (PMMA), poly vinyl alcohol (PVA), polyvinylpyrrolidone (PVP), triethylene glycol dimethacrylate (TEGDMA), and urethane dimethacrylate (UDMA) polymers using the Phy-X/PSD and Py-MLBUF software. The total stopping power (TSP) of electrons, protons, and alpha particles was calculated for the selected polymers using the ESTAR, PSTAR, and ASTAR programs. The effective atomic number for absorption and charged particle (electron, proton, alpha, and carbon ion) interactions were estimated for the selected polymers using Phy-X/ZeXTRa software. The FNRCS values of Bis-GMA, PCL, PEG, PMMA, and PVP were similar to those of the human tissues. For the selected polymers, the Zeff values for electron, proton, alpha, and carbon ion interactions of PCL, PEG, PLGA, and PVA were similar to those of human tissues, except for the cortical bone, across the entire energy range. These results are expected to assist in selecting suitable polymers as tissue-equivalent materials in the desired energy range for photon, neutron, and charged-particle interactions. This study is expected to be useful for radiation therapy and dosimetry.

Investigation of gamma-ray shielding parameters of bismuth phospho-tellurite glasses doped with varying Sm2O3.

The gamma ray shielding parameters such as mass attenuation coefficient, effective atomic number, equivalent atomic number, exposure buildup factor, and energy absorption buildup factor were determined for the 47.5P2O5+45ZnO+(5-x) Bi2O3+2.5TeO2 +xSm2O3 glass system using Phy-X/PSD software in the energy range from 0.015 to 15 MeV at penetration depths of 1-40 MFP. To understand the effect of Sm2O3 on gamma ray shielding parameters in selected glass system, the Sm2O3 was varied in the glass from 0.01 to 1 mol%. The calculated results show that the mass attenuation coefficient decreases with increasing photon energy but not influenced by the addition of Sm2O3. The Zeq values are lower in low (≤100 keV) and high energy regions (1 MeV-15 MeV) and higher in the medium energy region, indicating that the Compton scattering is significant in the medium energy region. The values of exposure buildup factors and energy absorption buildup factors are smaller in the low and high energy regions than in the intermediate energy region, indicating that the photo absorption and pair creation processes are important in the low and high energy regions, respectively. The 1% mole concentration of Sm2O3 in the selected glass shows higher exposure buildup factor and energy absorption buildup factor values in the intermediate energy region. The high density, high effective atomic number, and transparency to visible light of these materials indicate that they can be used as shielding materials in nuclear reactors and nuclear technology.

Solvent effect on absorption and fluorescence spectra of three biologically active carboxamides (C1, C2 and C3). Estimation of ground and excited state dipole moment from solvatochromic method using solvent polarity parameters.

The absorption and fluorescence spectra of three Carboxamides namely (E)-2-(4-Chlorobenzylideneamino)-N-(2-chlorophenyl)-4,5,6,7-tetrahydrobenzo[b]thiophene-3-carboxamide (C(1)), (E)-N-(3-Chlorophenyl)-2-(3, 4-dimethoxybenzylideneamino)-4,5,6,7-tetrahydrobenzo[b]thiophene-3-carboxamide (C(2)) and (E)-N-(3-Chlorophenyl)-2-(3,4,5-trimethoxybenzylideneamino)-4,5,6,7-tetrahydrobenzo[b]thiophene-3-carboxamide (C(3)) have been recorded at room temperature in solvents of different polarities using dielectric constant (ε) and refractive index (n). Experimental ground (µ(g)) and excited (µ(e)) state dipole moments are estimated by means of solvatochromic shift method and also the excited dipole moments are estimated in combination with ground state dipole moments. It was estimated that dipole moments of the excited state were higher than those of the ground state of all three molecules. Further, the changes in dipole moment (Δµ) were calculated both from solvatochromic shift method and on the basis of microscopic empirical solvent polarity parameter (E(N)(T)) and the values are compared.

Preparation and characterization of Eu(3+) doped powder spinel phosphors (MgAl(1.8)Y(0.2-x)O(4)).

The photoluminescence (PL) studies of powder phosphors are under rigorous study in view of the applications they have in the field of technology. Different methods are available for the preparation of rare earth ions doped in different host environment of powder phosphors. In the present work, a novel route known as sol-gel technique is employed to prepare spinel phosphor MgAl(1.8)Y(0.2-x)O(4):Eu(x) (x = 2-6 mol%). Then the studies have been carried out to optimize the dopant concentration in the host lattice with the help of photoluminescence spectra. These phosphors have displayed bright red color under UV source. The emission intensities were determined and the relative fluorescence intensities have been estimated. The richness of the red color has been verified by determining their chromaticity coordinates (X, Y) from the CIE standard charts. With the help of XRD, electron spin resonance (ESR), and photo-acoustic (PA) spectra of the samples prepared are also used for the confirmity of the host and analyzing of the data.