Modern Scientific Press

ABSTRACT: There is growing interest in biofuels in many developing countries as a means of ??????modernizing?????? biomass use and providing greater access to clean liquid fuels while helping to address energy costs, energy security and global warming concerns associated with petroleum fuels. At a time when the focus is on global warming, CO₂ emission, secure energy supply, and less consumption of fossil-based fuels, the use of renewable energy resources is essential. Biofuel has gained importance in the recent past year as a renewable fuel. The environmental issues concerned with the exhaust gases emission by the usage of fossil fuels also encourage the usage of biofuels which have proved to be eco-friendly far more than fossil fuels. Links between biofuels and sustainable development are varied and complex. On the one hand, biofuels may improve energy security, economic gains, rural development, elevate energy efficiency and reduce greenhouse gas emissions compared to standard fuels. On the other hand, production of energy crops could result in the expansion of the agricultural frontier, deforestation, monocropping, water pollution, food security problems, poor labour conditions and unfair distribution of the benefits along the value chain. The positive impacts and trade-offs involved vary depending on the type of energy crop, cultivation method, conversion technology and country or region under consideration. This paper seeks to provide a preliminary identification of the main sustainable development and environmental issues involved in the debate around production and trade of biofuels.

ABSTRACT: This study explores the potential of corn cob powder for adsorption of Cr(VI) in aqueous solution. Effects of adsorbent dosage, pH, temperature, contact time and Cr(VI) concentration were investigated. Maximum adsorption was observed at 80 ^oC under acidic condition of pH 4 with a contact time of 120 min. The percentage removal efficiency was more than 90% at lower initial Cr(VI) concentrations. Both Langmuir and Freundlich adsorption isotherms fitted reasonably well with the data and showed high correlation coefficient (R²) values of 0.999 and 0.991, respectively. Based on this, the adsorbent can be used as a low cost alternative in biosorption of wastewaters containing lower concentrations of Cr(VI).

ABSTRACT: In continuation of our earlier studies on Rhodobacter capsulatus KU002, the hydrogen producing abilities of this purple non sulphur phototrophic bacterium was investigated by limiting sulphate and phosphate. Alginate immobilization promoted higher amount of hydrogen than suspension cultures. More amounts of hydrogen were produced in lactate, with cystine at pH 7.0 ?????? 0.2 under sulphate limitation 0.4 mM concentration. Phosphate limitation using suspension or immobilized cultures could not induce any increase in hydrogen production. Significance of the above results in presence of existing literature is discussed.

ABSTRACT: Algae are the fastest-growing plants in the world, and this study demonstrates the production of algal biodiesel from Scenedesmus dimorphus. Biodiesel is an alternative fuel for conventional diesel, which is made from natural plant oils, animal fats, and waste cooking oils. This paper discusses the economics of producing biodiesel fuel from algae grown in open ponds. Microalgae have been identified as a potential biodiesel feedstock due to their high lipid productivity and the process conditions are milder than those required for pyrolysis and prevent the formation of by-products. Algae are very important as a biomass source. Algae will some day be competitive as a source for biofuel. Algae can be grown almost anywhere, even on sewage or salt water, and does not require fertile land or food crops, and processing requires less energy than the algae provides. Algae can be a replacement for oil based fuels, which is more effective and has no disadvantages. About 50% of their weight is oil. This lipid oil can be used to make biodiesel for cars, trucks, and airplanes. Microalgae have much faster growth-rates than terrestrial crops.

ABSTRACT: The released heavy metal from refinery effluents into the environment is a world major concern. Different studies have demonstrated that natural agents have high adsorption capacities for divalent metal ions. Cocoa pod husk is a natural adsorbent and in comparison with others and its availability in Southern Nigeria, is cost effective. In this study, the adsorption of heavy metals (Pb and Cu) from effluent water was investigated in batch condition. Activated carbon was prepared from cocoa pod husk, carbonized at 500 ^oC and impregnated with 1.0 M HCl at 700 ^oC in a muffle furnace for 2 hr. The resultant products were tested to adsorb the heavy metals in effluent water at varying pH, dorsage and contact time. The adsorption capacity and metal removal percentage was computed and recorded at the various varying parameters in the study; while the reaction attained equilibrium in 2 hr contact time. The maximum Pb removal efficiency was 78% at pH of 5.5 at a contact time of 1.9 hr and the maximum Cu removal from the effluent was 97% at pH of 5.6 and a contact time of 2 hr.

ABSTRACT: Present paper describes current status of biofertilizers in Indian agriculture. Biofertilizers are natural fertilizers that are microbial inoculants of bacteria, algae, fungi alone or in combination. They are defined as a product containing carrier based (solid or liquid) living microorganisms that are agriculturally useful in terms of nitrogen fixation, phosphorous solubilization or nutrient mobilization. They augment the availability of essential elements like nitrogen, potash, phosphorous, sulphur by directly supplying them or transforming them into soluble form. In addition, they also help plants to uptake several micronutrients. Types of biofertilizers viz., Rhizobium, Azospirillum, Azatobactor, blue green algae, blue green algae (BGA) inoculation, Phosphorous solubilizing biofertilizers, Mycorrhizea etc., are used predominantly in India.

ABSTRACT: Plastics and plasticulture are widely utilized and increasing in modern-day horticulture throughout the world. Plasticulture implies the use of plastics in agriculture in its broadest possible concept. Around the world, millions of tons of plastic are used each year for propagation, mulching, greenhouses and polyhouses, packaging/storage/silage, water management, polyethylene wax, low tunnels, shade houses nets, anti-hail nets, bird protection net, disease and pest management etc. Different grades of plastic material like low density polyethylene, high density polyethylene, polyethylene, polyethylene terephthalate, polystyrene and polypropylene etc are now available. Plastics are light in weight, versatile, available in different forms, higher strength, superior electrical properties, thermal insulation properties, excellent durability, superior flexibility, impermeability to water and gas, resistance to chemicals, smoother surface and have thus found a multitude of uses in crop production and landscaping. Plastic came to be accepted on the field due to their inherent superiority over conventional materials. Plastics have become synonymous with modern life but are difficult to dispose off and have become a significant source of environmental pollution. Biodegradable plastic are now a possibility as they are easily decomposed by microorganisms and persist for much shorter time in nature. Keywords: plastic; plasticulture; horticulture; greenhouse; mulching; packaging; environmental pollution; biodegradable plastic.

ABSTRACT: Mercury poisoning has become a problem of current interest as a result of environmental pollution on a global scale. Natural emissions of mercury form two-thirds of the input, and man-made releases form about one-third. Considerable amounts of mercury may be added to agricultural land with sludge, fertilizers, lime, and manures. The most important sources of contaminating agricultural soil have been the use of organic mercurial as a seed-coat dressing to prevent fungal diseases in seeds. In general, the effect of treatment on germination is favorable when recommended dosages are used. Injury to the seed increases in direct proportion to increasing rates of application. So an attempt was made on the impact of different concentrations of mercury on certain varieties of green gram (Vigna radiata L). Green gram was irrigated different concentrations of mercury. After on week exposure the seedlings were used for the morphological (seed germination, seedling growth, seedling fresh and dry weight) and biochemical estimations (chlorophyll, protein, amino acids and sugars). All the morphological and biochemical parameters are gradually decreased with the increase of mercury concentrations.