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In this paper, we present a review of the recent progresses in spray impingement heat transfer mechanisms and influences of various controlling parameters on spray impingement cooling performance. This paper focuses on the developments in spray cooling effectiveness achieved by modifying the flow processes and parameters. The open literature reveals that spray impingement cooling processes studies explore practical applications but not full understanding that can help to further improvement. There are many possibilities of improving the performance of spray cooling by alternating the fluid types, flow pattern and controlling parameters such as air/water pressure and to distance from nozzle to heated plate. Some of the earlier researchers have also tried pulsed spray impingement technique to enhance the heat transfer effectiveness during metal surface cooling. However, there remains a need for further examination and the present review discusses several such possibilities. [ABSTRACT FROM AUTHOR]

The impact of introducing SiO2 nanoparticles on the thermal conductivity (TC) values of various basefluids is presented in this paper. Microstructural properties of SiO2 nanoparticles were investigated using transmission electron microscope. Nanofluids were produced by dispersing SiO2 nanoparticles in water and commercialized engine coolant (CEC) at different mass concentrations in a range of 0.01–1%. Dynamic light scattering, visual examination, absorbance in the visible region, and zeta (ζ) potential analysis were introduced to investigate the size distribution and stability of nanoparticles in the dispersed phase. The results show that nanofluids had good dispersion stability. Enhancement in the TC of nanofluids was improved by increasing mass concentration and temperature. The TC improvement was more in CEC than in water. The highest enhancements in TC values of nanofluids were 21.08% and 1.89% with CEC and water respectively at a mass concentration of 1% and temperature of 65 °C. Finally, a new correlation of nanofluids TC has been proposed. [ABSTRACT FROM AUTHOR]

The concept of nanofluids has already shown that the heat transfer potential of traditional working fluids could be improved by dispersing various nanosized particles in them. Up to now, liquids are used as the base materials and dispersed nanoparticles are solid. In the present paper, we study solid nanoparticles dispersed in a gaseous medium (nanoaerosol), and the behavior of heat transfer of nanoparticles mixed with a gas flow is analyzed. Nanoparticles of Al2O3 mixed with an air stream are considered inside a tube subjected to a constant heat flux of 696.534 kW/m2. The timescale analysis of heat transfer in a nanoparticle–gas mixture is carried out. The effect of the particle volume fraction and the Reynolds number Re on the convective aerosol heat transfer coefficient and the Nusselt number is analyzed. The timescale study shows that conduction is dominant in a nanoaerosol. The maximum 59% and 55.27% enhancements in the convective aerosol heat transfer coefficient and the Nusselt number, respectively, are obtained with increasing the particle volume fraction in the range 0.002–0.01 and Re in the range 8000–20,000. These characteristics are compared with the values based on different correlations, and the results are shown to fall in the acceptable region. Moreover, particle inclusion and the rise in Re yield the maximum enhancement in the flow exit temperature equal to 1.72%. Finally, nanoaerosol-based coolants are recommended as the future of gas-based cooling systems. [ABSTRACT FROM AUTHOR]

Identification of markers associated with major physiological and yield component traits under moisture deficit stress conditions in preferred donor lines paves the way for marker-assisted selection (MAS). In the present study, a set of 183 backcross inbred lines (BILs) derived from the cross HD2733/2*C306 were genotyped using 35K Axiom genotyping array and SSR markers. The multi-trait, multi-location field phenotyping of BILs was done at three locations covering two major wheat growing zones of India, north-western plains zone (NWPZ) and central zone (CZ) under varying moisture regimes. A linkage map was constructed using 705 SNPs and 86 SSR polymorphic markers. A total of 43 genomic regions and QTL × QTL epistatic interactions were identified for 14 physiological and yield component traits, including NDVI, chlorophyll content, CT, CL, PH, GWPS, TGW and GY. Chromosomes 2A, 5D, 5A and 4B harbors greater number of QTLs for these traits. Seven Stable QTLs were identified across environment for DH (QDh.iari_6D), GWPS (QGWPS.iari_5B), PH (QPh.iari_4B-2, QPh.iari_4B-3) and NDVI (QNdvi1.iari_5D, QNdvi3.iari_5A). Nine genomic regions identified carrying major QTLs for CL, NDVI, RWC, FLA, PH, TGW and biomass explaining 10.32–28.35% of the phenotypic variance. The co-segregation of QTLs of physiological traits with yield component traits indicate the pleiotropic effects and their usefulness in the breeding programme. Our findings will be useful in dissecting genetic nature and marker-assisted selection for moisture deficit stress tolerance in wheat. [ABSTRACT FROM AUTHOR]

Most of the urban heat island (UHI) studies are carried out in densely populated cities but core industrial areas are also potential sites of heat island effect despite having a comparatively lower population. In the present study, heat island assessment has been carried out for Angul-Talcher industrial area (ATIA) which is one of the oldest industrial areas of India and is still undergoing a transformation to accommodate more industries and mining operations. As the major contributors towards influencing local meteorology were expected to be industrial (and mining) activities, the heat island was studied as "industrial heat island" (IHI) rather than urban heat island. Industrial and mining sites were the most frequent nighttime canopy-layer heat island intensity (HIN) hotspots due to anthropogenic heat of associated industrial processes as well as built structures. During the daytime, croplands experienced the most frequent canopy-layer HIN hotspots which could be attributed to low moisture of the soils during the non-farming period of the field campaign. Hourly maximum atmospheric heat island intensities were observed in the range of 7–9 °C. Monthly maximum HINs ranged from 2.97 to 4.04 °C while 3-month mean HINs varied from 1.45 to 2.74 °C. Amongst different land use/land cover classes, the highest mean canopy-layer heat island intensity for the entire 3-month-long duration of field campaign during nighttime was assessed at the mining sites (3-month mean 2.74 °C) followed in decreasing order by the industrial sites (2.52 °C), rural and urban settlements (2.13 °C), and croplands (2.06 °C). Corresponding daytime canopy-layer heat island intensity was highest for the croplands (2.07 °C) followed in decreasing order by the mining sites (1.70 °C), rural and urban settlements (1.68 °C), and industry (1.45 °C). [ABSTRACT FROM AUTHOR]

new charge distribution is proposed for the amino acids where each atom is associated with two point charges while each bond center is associated with one point charge. Centroids of charges arising due to atomic orbital hybridization called hybridization-displaced charges (HDC) and those located at the atomic sites and bond centers obtained by a modified form of the Mulliken scheme were combined. The density matrix calculations required for this analysis were performed at the B3LYP/6-31G** level of density functional theory. The combination of HDC centroids with the modified Mulliken charges was found to yield dipole moments and surface molecular electrostatic potentials (MEP) of the amino acids in good agreement with those obtained by rigorous DFT calculations or those obtained using the MEP-fitted CHelpG charges. This study shows that the combination of HDC centroids with the modified Mulliken charges is significantly superior to the conventional Mulliken charges. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Coal has been recognized as the most important source of energy generation in India. The present work was undertaken in order to assess the environmental impact of coal handling on peripheral land under near Kanika siding, Orissa, India. The data on suspended particulates in ambient air indicates an additional load of 50.5–108.7 μg/m3) to the ambient air due to coal loading which is equivalent to 50 × 365 to 108 × 365 kg/year. However, in the southern side (opposite to siding) covering the crop fields, the dust accumulation was maximum, i.e., 0.021 to 0.035 mg/cm2 area in comparison to 0.001 to 0.021 in the eastern side and 0.001 to 0.029 in western side of the crop fields. The physical and chemical properties of soil was also assessed. The results reveal that the coal loading has definite negative impact on the peripheral land near the site. [ABSTRACT FROM AUTHOR]

Reactions of the sulphonium ion of sulphur mustard (SM+1) at the N7, N3 and O6 sites of guanine, N7, N3 and N1 sites of adenine, O2 and N3 sites of cytosine and O2 and O4 sites of thymine were studied theoretically in gas phase and aqueous media employing density functional theory (DFT) and second order Møller–Plesset perturbation (MP2) theory. The B3LYP, B3PW91 and B1B95 functionals of DFT and the 6-31+G* and AUG-cc-pVDZ basis sets were used in the calculations. Basis set superposition error was treated using the counterpoise method by single point energy calculations at the B3LYP/6-31+G* level in gas phase. The present study explains the mechanism of alkylation of the DNA bases and shows that SM+1 would form stable adducts at the endocyclic nitrogen sites of the DNA bases, and at the O6 site of guanine and the O2 site of cytosine. Formation of adducts at the N7 site of guanine and N3 site of adenine are found to be most favored and next most favored respectively, which agrees with experimental observations. [ABSTRACT FROM AUTHOR]

Geometry of the CO2–H2O complex and reaction barriers leading to the formation of H2CO3were studied at the RHF/6-311++G**, MP2/6-311++G**, B3LYP/AUG-cc-pVDZ, B3LYP/AUG-cc-pVTZ, MP2/AUG-cc-pVDZ and CCD/AUG-cc-pVDZ levels of theory. The rotational barrier of the CO2–H2O complex and the reaction barrier leading to the formation of H2CO3–H2O from CO2–(H2O)2 were studied using the first three of the above-mentioned methods. Microsolvation of CO2 in water clusters having upto eight water molecules was studied using the B3LYP/AUG-cc-pVDZ method. Various methods except MP2/AUG-cc-pVDZ predict the equilibrium structure of the CO2–H2O complex to be symmetric while the MP2/AUG-cc-pVDZ method predicts it to be unsymmetric. Formation of H2CO3 from CO2–H2O is strongly catalyzed by the presence of a second water molecule. Atomic orbitals are strongly rehybridized in going from the equilibrium structures of the CO2–H2O and CO2–(H2O)2 complexes to the transition states involved in the formation of H2CO3 and H2CO3–H2O, respectively, as shown by hybridization displacement charges. [ABSTRACT FROM AUTHOR]

The article presents a study conducted by the Department of Environmental Sciences in Sambalpur University in Orissa, India on the inhibition and recovery kinetics of Acetylcholinesterase (AChE) activity in two tropical earthworms, Drawida calebi and Octochaetona surensis, exposed to carbaryl insecticides. The study reveals that D.calebi is more susceptible to carbaryl toxicity with higher rate of inhibition in AChE activity as compared to O.surensis. However, the rate of recovery from the insecticide stress was rapid in D.calebi as compared to O.surensis. Researchers believe that monitoring of AChE activity in earthworms can serve as a bioindicator to pesticide pollution in the soil subsystem.

Objective: To study the output indicators of a nutritional rehabilitation center to assess its performance. Methods: Data of 182 children aged between 6-59 months with severe acute malnutrition in a nutritional rehabilitation center were analyzed retrospectively. Identification and treatment of severe acute malnutrition was done according to World Health Organization recommendations. Results: The recovery rate, death rate, defaulter rate, mean (SD) weight gain and mean (SD) duration of stay in the nutritional rehabilitation center were 68%, 2.2%, 4.4%, 13.0 (9.0) g/kg/d, 12.7 (6.8) days, respectively. Conclusion: Nutritional rehabilitation centers are effective in management of severe malnutrition. [ABSTRACT FROM AUTHOR]