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In fracture mechanics, it is important to understand the fracture parameters, several strides in these studies have resulted in various analytical formulations. In this work, important analytical formulations of stress field data are revisited. Though the interpretation of stress field data is well studied, the possibility of utilizing principal stress orientation in order to estimate fracture parameters have not been properly investigated. This work attempts to shed some light on that possibility by studying the principal stress orientations for fracture problems using different formulations. In this work, only mode-I problems are considered and whole field stress fields are generated for different analytical formulations. The principal stress values and orientations are determined using Eigenvalue and Eigenvector approach and the principal stresses are studied. It is found that the principal stress orientations are insensitive towards the change in stress field parameter in the case of single parameter equation. In the case of multi parameter equations it was found that principal stress orientations have variation with respect to the stress field parameters.

A comparative life cycle assessment of CO2 capture potential of microalgae, Scenedesmus dimorphus, during autotrophic cultivation in closed airlift photobioreactor and open raceway pond under Indian conditions has been carried out. The LCA inventory inputs for the both the systems were entirely based on primary experimental data obtained by algal cultivation in 1000-L pilot-scale raceway pond and 5-L airlift photobioreactor, respectively. The primary energy demand, environmental impacts and Net CO2 capture efficiency of both the systems were evaluated. The results indicated that the primary energy demand and GWP of airlift photobioreactor were 3.7-fold higher than raceway pond. The NERCO2 (defined as net emission ratio of CO2 and estimated as ratio of CO2 sequestered/CO2 emitted) of raceway pond was fourfold higher as compared to airlift photobioreactor; however, both the cultivation systems were observed to be net negative in terms of CO2 sequestration. However, the process can become net CO2 positive, with up to fourfold and 7.5-fold enhancement in biomass productivities (wrt base value) for raceway pond and airlift photobioreactor, respectively. Further, LCA predictions indicated that utilization of energy-efficient motors with lower specific energy consumptions for microalgae cultivation would facilitate algal cultivation systems to achieve net CO2-positive sequestration.

Tremendous researches are progressing on Aluminum Matrix composites to get along with extensive use in applications such as automobile, aerospace, marine etc. The present technology demands affordable reinforcement of industrial wastes to produce composite materials. Recent studies have shown that flyash is one of the industrial wastes for reinforcement along with Aluminum alloys which enhances the mechanical properties. The use of flyash in Aluminum Alloys reduces the density and improves the strength of composites. In the current study, the results obtained from the reinforcement of flyash in A356 alloy for various volume percentage are investigated and enhancement in the mechanical properties of automobile application (Piston) is analysed. Variation of structural properties such as deformation and strain variations are obtained. It is observed from the analysis that total deformation, directional deformation and equivalent elastic strain decreases with the addition of flyash to alloy. It is also seen that as the volume percentage of flyash increases, deformation decreases and the least deformation is observed for A356 Al C12(S)

Hydration kinetics of red lentil seeds were carried out for whole, dehusked and splits at different temperatures (15 to 45 °C). Several physical properties were evaluated as function of soaking temperatures. Henderson and Pabis, Page, two term exponential and Peleg models were fitted to the obtained hydration kinetics data. To assess the adequacy of models three statistical parameters, coefficient of multiple determinations (R2), root mean square error (RMSE) and chi-square (χ2) were employed. Peleg model (R2 > 0.990; RMSE

The freshwater green algae, Scenedesmus obtusus, was cultivated in a 3.4 L airlift photobioreactor. The hydrodynamic parameters were estimated at different inlet gas flow rates (1, 2, 3, and 4 LPM) and their subsequent impact on the growth and biochemical characteristics of microalgae was studied. The biomass concentration and productivity increased with an increase in flow rates from 1 to 4 LPM. A maximum of 0.07 g L-1 day(-1) productivity of biomass was attained at 3 LPM. An increase of total carbohydrate content from 19.6 to 26.4% was noticed with increment in the inlet flow rate of gas from 1 to 4 LPM. Major variations in total fatty acid content were not observed. The impact of light irradiance on growth and biochemical characteristics of S. obtusus was also evaluated. A maximum biomass productivity of 0.103 g L-1 day(-1) was attained at an illumination of 150 mu mol m(-2) s(-1) under continuous light. The major fatty acids reported were palmitic acid (C16:0), alpha-linolenic acid (C18:3), linoleic acid (C18:2), and oleic acid (C18:1). Biodiesel properties of the microalgae were estimated under various culture conditions. The light profile inside the airlift reactor was experimentally measured and the predictive modelling of light profile was also attempted.

The present study was carried out to study the physico-chemical changes that take place in both product and oil during the deep fat frying of a traditional savoury snack ‘kodubale’, at 120–160 °C for 120–600 s using coconut oil (CO) and nutra-coconut oil (NCO). Further, kinetic studies on moisture loss, oil uptake, color and degradation of β-carotene, total polyphenol content and antioxidant activity for kodubale was carried out during frying as a function of temperature and time. The study showed that the kinetic coefficients for above parameters increased with temperature and time and the data obtained were well fitted with first order kinetic model. The results also revealed that NCO fried product retained major phenolic acids due to the presence of antioxidants in the NCO which was enriched with flaxseed oil concentrate. The fatty acids profile of oil extracted from products obtained by frying using NCO was characterized with higher ω-3 and ω-6 fatty acids content as compared to same obtained using CO. However, the breaking strength and sensory characteristics of CO and NCO fried kodubale was found to have no significant difference (p

Scenedesmus obtusus, a freshwater microalga, was evaluated for its growth and biochemical characteristics under various culture conditions. S. obtusus was tolerant at all tested CO2 concentrations up to 20%. Among the different nitrogen sources, urea showed enhanced biomass productivities up to 2-fold compared to control, where the nitrogen source was sodium nitrate. Light intensity and photoperiod had a significant effect on growth rate and biomass productivity. The growth rate was observed maximum under continuous light exposure at the light intensities, 30μmolm(-2)sec(-1) and 60μmolm(-2)sec(-1) The species was able to tolerate the salinity levels up to 25mM NaCl, where, the increase in the concentration of NaCl suppressed the growth. Ammonium acetate and glycine showed better growth rate and biomass productivity indicating mixotrophic ability of S. obtusus. Supplementation of acetate and bicarbonate significantly enhanced the biomass productivity. Biodiesel properties of S. obtusus cultivated at various culture conditions were estimated.