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Galactomannans based biopolymers are common constituents of ungerminated seeds of numerous leguminous plants present in endosperm of seeds. They are highly valuable in industries due to their ability to modify the flow behavior of aqueous solutions viz. thicken, suspend, gel, stabilize, swell and film formation. Consequently, they have diverse applications in food and non-food due to their biocompatibility, biodegradability, sustainability and abundance. Cassia occidentalis, an annual weed occurring throughout India is a rich source of seed galactomannans (∼30% endosperm). The gum derived from seed endosperm can be potentially utilized in a number of industries to replace the conventional expensive gums. However, the extracted gum has considerable disadvantages such as uncontrolled hydration, changes in viscosity during storage, pH-dependent solubility, lower shelf life etc, thereby, limiting their vast industrial applications. Intriguingly, these limitations can be overcome by functionalization of hydroxyl groups. Therefore, grafting onto C. occidentalis seed gum was carried out with acrylonitrile in presence of ceric ammonium nitrate under inert atmosphere. The reaction conditions were optimized by varying concentration of CAN, nitric acid, acrylonitrile, reaction temperature and time. The grafted gum was characterized using FTIR, TGA, DTG, X-Ray and SEM analysis. [ABSTRACT FROM AUTHOR]

Due to the rapid depletion of petroleum fuel, researchers throughout the world are looking for alternative fuels to run engines. Today biodiesel is a prime candidate as an alternative to diesel fuel. Reduction in pollution adds to the merits of biodiesel. Various aspects of engine performance using Neem-Diesel blend (B-20) as fuel were studied through extensive experimentation at different injection pressures on a single cylinder direct injection diesel engine. Data thus obtained were analyzed and compared with those of pure diesel. Significant reduction in the NOx concentrations, smoke density, and CO and HC emissions were observed. At the same time no significant effect on brake specific fuel consumption and brake thermal efficiency were observed. Based on these results 1.57 kN/cm2 was found to be the optimum injection pressure for Neem-Diesel blend (B-20). [ABSTRACT FROM AUTHOR]

Inedible vegetable oils that can be extracted from unexploited forest produce can provide solutions to energy requirements at the grass roots level, thus obviating dependence on fossil fuels. Short-term compression ignition engine tests were carried out using karanj (Pongamia pinnata) oil alone and also by blending it with diesel. The calorific value of karanj oil was 14.77% less than that of diesel. Due to its high viscosity (28.63 at 40°C), the brake specific fuel consumption and brake thermal efficiency were observed to be higher and lower, respectively, in the case of karanj oil, than those obtained from diesel. But, by blending karanj oil with diesel, the difference was minimized. The performance of karanj oil was comparable to that of diesel when blended with it in 20:80 (v/v) ratios. The smoke density and total hydrocarbons in the emissions of K20 blend were higher than that of diesel fuel, but considerable reductions in CO and NOx were obtained. [ABSTRACT FROM AUTHOR]

Due to high self-ignition temperature, LPG fuel alone cannot be used to run compression-ignition (CI) engines. A pilot fuel is required to initiate combustion at the end of compression stroke. Diesel fuel can be utilized as pilot fuel, but as the fossil fuels are depleting fast and also pollute the environment when burned, an alternative, renewable and environmentally friendly fuel in the form of methyl esters of Pongamia Pinnata was considered in the current investigation, which included engine performance and exhaust emission tests at different loads at an injection pressure of 170 kgf/cm2. The performance of an engine in dual fuel mode was comparable to that obtained when the engine was run alone on diesel. Moreover, reductions in smoke density and NOx were observed. However, in this mode, an increase in CO and HC emissions were observed. [ABSTRACT FROM AUTHOR]

Bamboo, a lignocellulosic material, is a renewable resource of interest as feedstock for production of cellulosics by chemical functionalization. The present paper describes the cyanoethylation of cellulose isolated from Dendrocalamus strictus bamboo in which the effect of different reaction conditions was studied with respect to maximum degree of cyanoethylation. Optimum conditions for preparation of a fibrous and organosoluble cyanoethylcellulose (DS 2.2) comprised of aqueous NaOH concentration 12%, alkalization temperature 20°C, acrylonitrile concentration 90 mol/AGU, cyanoethylation time 0.75 h and temperature 55°C. [ABSTRACT FROM AUTHOR]