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Cysteine plays a critical role in maintaining normal human metabolism, redox homeostasis, and immune regulation. Despite its functional versatility, cysteine metabolism in the human body is not well understood because of the lack of a robust tool for real-time measurement of cysteine at the cellular and sub-cellular level. In the present study, a genetically encoded nanosensor was developed using Cj0982 protein of Campylobacter jejuni , Enhanced Cyan Fluorescent Protein (ECFP) and Venus. The Cj0982 was sandwiched between ECFP and Venus for the construction of the nanosensor, named as Cys-FS (Cysteine-Fluorescent-Sensor). The Cys-FS is pH stable, specific to cysteine and has an affinity of 1.2 × 10−5 M. A range of affinity mutants were also developed with a cumulative cysteine detection range from 800 nM to 3.5 mM. The Cys-FS nanosensor was expressed in bacterial, yeast and mammalian cells, and the dynamics of cysteine level was measured in living cells using the confocal microscopy. The results showed that the Cys-FS nanosensor successfully monitored the dynamics of cysteine in both prokaryotic and eukaryotic systems without disrupting the cell. Thus, this study presents a novel nanosensor that can measure cysteine in living cells. This nanosensor is minimally invasive and non-toxic. • A genetically encoded FRET based nanosensor was developed for real-time monitoring of cysteine in living cells. • The sensor consists of Cj0982 protein from Campylobacter jejuni flanked by Enhanced Cyan Fluorescent Protein and Venus. • Conformational Change in Cys-FS sensor in presence of cysteine results in modulation of FRET ratio. • The sensor has a highly specific response to cysteine with an in vitro dissociation constant of 1.2 × 10−5 M. • The sensor is appropriate for real-time imaging of cysteine in bacterial, yeast and mammalian cells [ABSTRACT FROM AUTHOR]

Rapid industrialisation and excessive use of fossil fuel resources has led to growing concern for development of next generation fuel sources. So, the exaggerated to be fulfilled and to curb the problem of increasing fuel prices; researchers are putting their efforts to produce an alternative fuel from replenish-able resources on large scale. Biodiesel is one of the promising biofuels as a replacement to petroleum diesel in future. Transesterification is most adopted technique to produce biodiesel and generally methanol is used as reactant in transesterification. Biodiesel produced by using methanol as alcohols cannot be termed as completely renewable as methanol is derived from fossil resources. To make it completely renewable, alcohol derived from bio-based resources should be adopted. In this paper, an attempt has been made to make use of higher alcohol propanol, butanol and pentanol is used for biodiesel production process and reaction parameter catalyst, time, temperature, molar ratio are optimised with application of Response Surface Methodology (RSM) by using Design Expert software. The result of experimental investigation shows that optimised biodiesel yield was obtained maximum for 1-butanol (76.4%), for 1-pentanol (73.13%) and minimum for 2-propanol (56.86%). The comparative analysis of biodiesel obtained from different alcohols shows that all the resultant biodiesel properties meets the Indian Standard 15607 standard, while the result also indicates that Karanja Oil Pentyl Ester (KOPnE) had superior cold flow properties with viscosity marginally higher among all biodiesels. [ABSTRACT FROM AUTHOR]

Extensive use of fossil fuel resources especially petroleum has resulted in situation to look for alternative fuel sources. Biodiesel offers a good choice due to its renewable nature. In recent times, mainly methanol has been used in transesterification reaction for biodiesel production as it is derived from fossil sources, and biodiesel produced cannot be termed as completely renewable while other alcohols such as ethanol, being obtained from renewable sources such as potatoes, sugarcane, grains, corn and sorghum can be used for transesterification reaction. The aim of this work was to investigate the impact of ethanol on biodiesel production from Karanja oil and then optimise process variables for transesterification process. Further a comparison was done in optimised reaction parameters for methanolysis and ethanolysis. The result of experimental investigation shows that Karanja biodiesel yield of 91.05% was achieved with molar ratio of 10.44:1 for methanol using 1.22% w/w KOH as catalyst for 90.78 min at the temperature of 66.8 °C. On the other hand for, ethanolysis, optimised reaction conditions were, 8.42:1 molar ratio, 61.3 °C reaction temperature with 1.21% of catalyst and 120 min of reaction time to obtain yield of 77.4%. [ABSTRACT FROM AUTHOR]

Biodiesel is one of the prospective alternatives to petroleum fuel resources because of its renewable and environment friendly nature. Transesterficiation process is used for biodiesel production. The biodiesel production process mainly depends on five parameters which includes free fatty acid (FFA) content, type of alcohol used and molar ratio (alcohol:oil), catalyst type and its concentration, reaction temperature and time. Methanol and ethanol are commonly used for biodiesel production in presence of different alkaline catalysts like sodium and potassium hydroxides. The production methodology of biodiesel is an important aspect for efficient and cost-effective production of biodiesel. The present study focuses on the various technical aspects of biodiesel production methodology. The study reveals that for optimum biodiesel production reaction temperature should be in range of 50–60 °C, molar ratio of alcohol to oil should be in range of 6–12:1 with the use of an alkali catalyst having optimum concentration 1% by weight. The optimal reaction time for transesterification process is 120 min. [ABSTRACT FROM AUTHOR]

The Advanced Heavy Water Reactor (AHWR) is a vertical pressure tube type, heavy water moderated and boiling light water cooled natural circulation based reactor. The fuel bundle of AHWR contains 54 fuel rods arranged in three concentric rings of 12, 18 and 24 fuel rods. This fuel bundle is divided into number of imaginary interacting flow passage called subchannels. Transition from single phase to two phase flow condition occurs in reactor rod bundle with increase in power. The two phase flow regimes like bubbly, slug–churn, and annular flow are normally encountered in the rod bundle of reactor. Prediction of thermal margin of the reactor has necessitated the determination of turbulent mixing rate of coolant among these subchannels under these flow regimes. Thus, it is vital to evaluate turbulent mixing between subchannels of AHWR rod bundle. In this paper, experiments were carried out to determine the two phase turbulent mixing rate under bubbly flow regime in the simulated subchannels of the reactor. The size of rod and the pitch in the test was same as that of actual rod bundle in the prototype. Three subchannels are considered in 1/12th of the cross section of the rod bundle. Water and air was used as the working fluid and the turbulent mixing tests were carried out at atmospheric condition without heat addition. The void fraction was varied from 0 to 0.3 under various range of superficial liquid velocity. Turbulent mixing rate was experimentally determined by adding tracer fluid in one subchannel and measuring the concentration of that in other subchannels at the end of the flow path. The test data were compared with existing models in literature. It was found that existing models could predict the measured turbulent mixing rate in the rod bundle of reactor within range (average error) of ±66%. [ABSTRACT FROM AUTHOR]

The aim of this paper is to study techno-economic feasibility of microhydro–photovoltaic–biomass and biogas–diesel–battery hybrid energy system (HES) in off-grid mode for a rural area in Uttarakhand state, India. The considered HES is designed for energy access in 5 un-electrified villages. Size optimization and sensitivity analysis of considered system is performed by using HOMER software in order to meet the electricity requirements of study area. The selection of optimum configuration is based on the lowest value of cost of energy (COE) and net present cost (NPC) along with the maximum value of renewable fraction (RF) and lowest harmful emissions (CO 2 ). By considering economy and environment as the main concerns, comparative analysis of four different types of models is presented here. Based on sensitivity analysis, 3 configurations out of four different models are selected. By considering economy and environment as the main driving factors, one configuration out of three configurations, is selected as the optimum configuration for the study area which comprises total NPC $5,33,654, COE $0.197/kW h, RF 94% and CO 2 emission 15,930 kg/yr. [ABSTRACT FROM AUTHOR]

In developing countries, quantities of solid waste generation is increasing day by day and most of which is disposed off through landfilling and open dumping resulting into the release of significant quantities of GHG. CH 4 , the major gas produced by these activities, is known to cause global warming. The paper reports the estimates of CH 4 calculated by using IPCC Default, FOD method and LandGEM model, version 3.02 from Panki open dump site of Kanpur, India. The annual average CH 4 emission rates from Panki open dump site is found as 197.33, 24.27 and 25.14 Gg by IPCC Default method, FOD and LandGEM respectively for the period 2010-2030. The study reveals that IPCC Default method over estimate the result therefore it is not recommended for open dump site. however, LandGEM is recommended over FOD method for open dumps due to the fact that [a] estimates of CH 4 emission is very near to GHG emission by FOD method [b] simplicity in model parameters [c] avoidance of over estimation, if parameters are calculated as per the actual site conditions. So the present study reveals that LandGEM provides better estimation compared to other method and the CH 4 emission rate is found as 25.14 Gg/year for the Panki open dump site, Kanpur. The assessment of methane emission potential reveals the fact that upgrading the open dumps into landfill increases the methane emission rates and their utilization potential and adding the landfill to fill the future needs and utilization of landfill gases. [ABSTRACT FROM AUTHOR]

Due to rapid industrialisation and use of advanced technologies there has been increase in the consumption of fossil fuels, especially petroleum. Increasing needs are reciprocally proportionate to diminishing reserves of coal and petroleum. So, the exaggerated to be fulfilled and to curb the problem of increasing fuel prices; researchers are putting their efforts to produce an alternative fuel from replenish able resources on large scale. Biodiesel itself is proving to be a reliable and competent competitor to non-renewable petroleum which is being produced from commonly accustomed plants for instancerapeseed, soybean, sunflower and palm etc. But, complication is that it becomes a problem for in-availability of these oils for foods. Now non-edible raw materials oils such as Pongamia, Jatropha, Mahua, Moringa seed oil etc. have been used to raise the standard of these oils and being produced to complete the level of petroleum and be proven as the best resources for biodiesel production in all approaches both technically and economically. In this paper emphasis has been laid down to review the impact of higher alcohols, use of different raw materials for biodiesel preparation and effect of their composition on Oxidation Stability and Cold Flow properties. Moreover, various production technologies used to produce biodiesel were also reviewed and comparison was done among them for better yield. Further, an attempt has been made to investigate the effect of higher alcohols on biodiesel yield and its properties. The study concludes that oxidation stability depends upon unsaturation mainly linoleic acid and lenolenic acid. Moringa olifera , Moroccan frying oil, Schleichera oleosa L. oil, Moringa peregeria are prospective oils as per oxidative stability characteristics. In contrast to it, cold flow properties depend upon saturation and suggests that having more saturated fatty acids result in poor cold flow properties. [ABSTRACT FROM AUTHOR]

Renewable energy, a viable alternative of the world, can overcome the energy crisis that hinders growth of today's economies. The present work includes sizing of hybrid energy system using various energy management strategies. The energy management strategies considered in the present work are cycle charging strategy, load following strategy and peak shaving strategy. The sizing of hybrid energy system for all the mentioned strategies are carried out using genetic algorithm, particle swarm optimization and biogeography based optimization techniques by keeping energy index ratio at 1. The model also incorporates net present cost, cost of energy, renewable fraction and emissions of carbon di-oxide from diesel generator. From the analysis, it can be concluded that the 10th combination of cycle charging strategy is most cost effective as compared to other dispatch strategies. Seven unelectrified villages of Dhauladevi block of Almora district in Uttarakhand, India, has been selected for the development of hybrid energy system, comprising of renewable energy resources available locally along with the addition of diesel generator, for meeting the energy deficit. The results show that cycle charging strategy is most cost effective compared to load following and peak shaving strategies, with a minimum cost of energy value of 5.64 ₹/kWh. [ABSTRACT FROM AUTHOR]

Wind generation is currently the major form of new renewable, generation in the world. The wind power is totally dependent on wind flow, due to randomness and uncertainty of wind flow, the wind power generation is quite fluctuating in nature and large scale wind farms may cause significant impact to the power system safety, quality and stability. The active power mainly depends upon the potential of the wind power produced and wind turbine generator design. The reactive power demand on the other hand depends upon conversion devices and recovered power quality fed to the grid. The wind farms which accesses to power grid cause fluctuations and reactive power redistribution and sometimes lead to voltage collapse. Similarly, the dynamic voltage stability is a major challenge faced by distribution network operators. The easy solution comes into picture is to install reactive power source devices with optimization of the existing assets to deliver enhanced reactive power to the grid. With solution to reliability, voltage regulation, reactive power requirements, grid integration problems, weak grid interconnection, off grid wind power generation and its integration to power grid, wind power penetration in distribution grid, wind power uncertainty, flicker and harmonics etc. The categorization of issue considered the goal of our work is the reactive power management of wind farm in most technical and economical way without compromising quality power system voltage, and considering the wind turbine technology for already commissioned wind farm, and change in WT technology in present scenario. More than 100 research publications on voltage and reactive power control of wind farms, extending from year 2003 to 2013 have been critically examined, classified and listed for quick reference. [ABSTRACT FROM AUTHOR]

In recent years, renewable energy can be seen as one of the important prospect of today's research, as it is likely to enlighten the lives of millions of people by fulfilling demand of electricity in their daily life. The present work focuses on the development of optimal hybrid energy system sizing model based on comparative analysis of particle swarm optimization, genetic algorithm and Homer software for energy index ratio of 1. The model also incorporates renewable fraction, emissions of carbon di oxide from diesel generator, net present cost and cost of energy. The system is developed to supply the demand of 7 un-electrified villages of Dhauladevi block of Almora district in Uttarakhand, India with the help of the available resources of solar, hydro, biomass and biogas energy along with the addition of diesel generator, for meeting out the energy deficit. From the optimization results, minimum cost of energy and maximum renewable fraction are obtained as 5.77 Rs/kWh and 92.6% respectively. [ABSTRACT FROM AUTHOR]

In recent years, the energy for the development of world economy depends entirely on fossil fuels which are not only rapidly depleting but are also causing environmental degradation. This situation has attracted the attention of world’s countries to develop alternative biofuels as a substitute of petroleum fuels. Biodiesel, the alkyl esters of vegetable oils, is being given top priority for its production from edible, non-edible and microalgal oils as feedstocks and has properties almost similar to diesel except oxidation stability and cold flow properties that may render the use of biodiesel for engine operation difficult. In this study, the efforts are made to classify different oils on the basis of oxidation stability index (OSI), so that one can select the oils with high OSI for the production of biodiesel which do not require additives to enhance the fuel stability and the biodiesel quality would remain unchanged for the period of OSI and before that, the fuel is expected to be entirely utilized for engine operation. Based on American Society for Testing and Materials (ASTM) D-6751 and European EN-14214 standard for OSI, the oils are classified into three main categories namely best, moderate and poor oils. As per this classifications, 19 non-edible and 19 microalgal oils are found as the best, 9 nonedible and 7 microalgal oils as moderate and 13 non-edible and 6 microalgal oils as poor oils. As per availability and OSI, the best oils can be recommended for the production of biodiesel which can be directly used for engine without any quality problem. This classification would help the biodiesel producers/industries to select oils that can be converted to biodiesel requiring no additives. While the biodiesels from other oil categories would require stabilisation using antioxidants and would be relatively costlier than the biodiesel from the best oils. [ABSTRACT FROM AUTHOR]

The present paper implements the Box–Behnken response surface methodology for maximizing the biodiesel yield from Pongamia oil by optimizing the four process variables. A biodiesel yield of 98.4% was achieved with methanol/oil molar ratio (11.06:1) using KOH as catalyst (1.43% w/w) in 81.43 min at a temperature of 56.6 °C. But the major problem associated with Pongamia biodiesel is its poor oxidation stability. This paper also investigates the methodology to improve the oxidation stability characteristics of Pongamia biodiesel. The result of investigation show that the use of antioxidant Pyrogallol (200 ppm) significantly improve the induction period from 1.83 h to 6.5 h for Pongamia biodiesel while PB 10 blend can maintain its stability without any antioxidant. [ABSTRACT FROM AUTHOR]

Abstract: Due to rapid price increase in petroleum fuels, there is a growing demand for the search for sustainable, environment friendly and cost effective alternative substitute renewable fuel. Out of various available sources straight vegetable oils (SVOs) from edible oil and non-edible oil resources abundantly available in India are selected. Five edible and four non-edible selected SVOSs are analysed on the basis of composition of fatty acids. Oxidation Stability Index and cold flow properties are computed and SVOs are graded for biodiesel production. The result found that SVOs in order of decreasing OSI are Castor>Mahua>Neem>Karanja can be recommended as potential feed stocks for biodiesel production while other SVOs are not due to their instability but may require considerable effort to make the fuel stable. CP and CFPP of edible SVOs in decreasing order are found: Castor>Rape seed>canola> Soya bean while non-edible SVOs in decreasing order are Mahua>Neem>Karanja>Jatropha>Soybean indicating that there is a need to improve the cold flow properties using additives. Out of all SVOs the Castor oil has highest OSI and good cold flow properties and recommended as the best SVO for biodiesel production. [Copyright &y& Elsevier]

Abstract: Pongamia is forest-based tree containing non-edible oil and has a large production potential of biodiesel which can grow on any type of soil, needs minimum input and management, have low moisture demand, productive life is more than 40 years and seeds have 28–34% oil content. Biodiesel yield of 99% is obtained from Pongamia oil by transesterification under the molar ratio of 6:1 of alcohol to oil with Sodium hydroxide as a catalyst of 0.5vol% and operating temperature of 60°C with time for production process being 1h. The study shows that brake specific fuel consumption and brake thermal efficiency of B20 biodiesel from Pongamia is quite comparable to diesel. The hydrocarbon and carbon monoxide gas emissions are quite low in case of Pongamia biodiesel as compared to diesel. This paper describes the various aspects of Pongamia as potential fuel in India. [Copyright &y& Elsevier]

Abstract: In the view of rapid depletion of fossil fuels and rise in price of crude oil, there is emergent focus and need to search for alternative fuels. As we know that there is huge demand of diesel for transportation sector, captive power generation, agricultural sector and industrial sector, to accommodate those demands biodiesel is being viewed as a substitute for diesel. Biodiesel is an engine fuel that is prepared by chemical reaction of fatty acids and alcohol, which usually means combining vegetable oil with methanol in the presence of a catalyst (usually sodium hydroxide). But before using biodiesel as a substitute for engine fuel, there are two major problems associated, first one is “cold flow property of biodiesel” and second one is termed as “stability of biodiesel”. In this paper our main focus will be on cold flow property of biodiesel and its impact on engine performance. Some of the cold flow properties such as cloud point, pour point and cold filter plugging point are responsible for solidification of fuel causing blockage in fuel lines filters which further leads to fuel starvation in engine operation during starting operation. This paper also provides several remedial measures for improving the cold flow properties of biodiesel. [Copyright &y& Elsevier]

Highlights: [•] Stability of metal contaminated biodiesel blend has been checked. [•] Effectiveness of different antioxidants has also been checked. [•] Biodiesel blends with diesel have shown the better oxidation stability. [•] Effect of metals on the oxidation stability of biodiesel has found catalytic. [Copyright &y& Elsevier]

Highlights: [•] Present paper reports the storage stability studies of Jatropha curcas biodiesel (JCB). [•] Various correlations were developed for storage stability. [•] These correlations can be used to predict the amount of antioxidants required for stabilizing the biodiesel. [ABSTRACT FROM AUTHOR]

Abstract: The aim of the present study is to investigate engine performance and the exhaust emissions of a diesel engine using oxidatively stabilized biodiesel. Biodiesel fuel used in the study was prepared from Jatropha curcas oil. Different samples with various metal contaminants, generally available in the metallurgy of the containers are oxidatively stabilized with antioxidant (PY) according to EN 14112. The brake specific fuel consumption (BSFC) of biodiesel fuel with and without antioxidant is more than that of petro-diesel fuel. The BSFC of biodiesel fuel with antioxidants is lesser than that of biodiesel fuel without antioxidants, but no specific trends were detected according to the type of metal content and amount of antioxidants. The combustion characteristics and exhaust emissions in diesel engine were not influenced very much by the addition of antioxidants in biodiesel fuel. Also performance and emission characteristics of unstablized biodiesel and stabilized biodiesel (stabilized for 6months) are measured with respect to time. [Copyright &y& Elsevier]

Abstract: Recently, world has been confronted with an energy crisis due to fossil fuel depletion and environmental degradation. Biodiesel is one of the most promising alternative fuels to meet these problems. However the oxidation stability and thermal stability are the problems which are faced while we are going for commercial application of biodiesel. There are standards available discussing the minimum specification of oxidation stability of biodiesel while using in IC engine but at the same time there is no specification is available for thermal stability. Specification for thermal stability can be developed if one can develop the relationship between oxidation and thermal stability. The present paper deals with the development of relation between the oxidation stability and thermal stability which will further be useful for the development of such specifications for thermal stability of biodiesel. [Copyright &y& Elsevier]

Abstract: The vegetable oil, fats and their biodiesel suffer with the drawback of deterioration of its quality during long term storage unlike petroleum diesel because of large number of environmental and other factors making the fuel stability and quality questionable. There are various types of stabilities such as oxidation, storage and thermal, playing key roles in making the fuel unstable. In the present paper the thermal stability of Jatropha curcas biodiesel (JCB) as engine fuel was studied. The thermodynamic parameter of activation energy (E a) of the samples was determined by direct Arrhenius plot. The results show that the thermal degradation of all JCB samples can be treated as a first order reaction. It seems at this stage that the additives under study can offer a significant solution in inhibiting the degradation rate of biodiesel. The pyrogallol (PY) has been found to have more pronounced effect on the onset temperature (T on) as well as on the E a followed by propyl galate (PG)>tert-butyl hydroquinone (TBHQ)>butylated hydroxytoluene (BHT)>butylated hydroxyanisole (BHA). The results may have important applications in the development of JCB as engine fuel. [Copyright &y& Elsevier]

Abstract: Biodiesel, an ecofriendly and renewable fuel substitute for diesel has been receiving the attention of researchers around the world. Due to heavy import of edible oil, the production of biodiesel from edible oil resources in India is not advisable. Therefore it is necessary to explore non-edible seed oils, like Jatropha curcas (J. curcas) and Pongamia for biodiesel production. The oxidation stability of biodiesel from J. curcas oil (JCO) is very poor and therefore an idea is given to increase the oxidation stability of biodiesel by blending it with petro-diesel. J. curcas biodiesel (JCB), when blended with petro diesel leads to a composition having efficient and improved oxidation stability. The results have shown that blending of JCB with diesel with less than 20% (v/v) would not need any antioxidants but at the same time, need large storage space. Similarly, if the amount of diesel is decreased in the blend, it will require the addition of antioxidant but in lesser amount compared to pure JCB. For the purpose five antioxidants were used namely butylated hydroxytoluene (BHT), tert-butyl hydroquinone (TBHQ), butylated hydroxyanisole (BHA), propyl gallate (PG), and pyrogallol (PY). A B30 blend (30% JCB in the blend of JCB and petro-diesel) has been tested for the same purpose. PY is found to be the best antioxidant among all five antioxidants used. The optimum amount of antioxidant (PY) for pure biodiesel tested for the present experiment is around 100ppm while it is around 50ppm for B30 blend to maintain the international specification of oxidation stability. [Copyright &y& Elsevier]

Abstract: The present paper reports the results of the study of the effect of metal contaminants on the storage stability of Jatropha curcas biodiesel (JCB) with and without antioxidants. Taking 1,2,3 -Trihydroxybenzene/Pyrogallol (PY) as the most effective antioxidant based on the earlier work of the authors, JCB was mixed with different transition metals – Fe, Ni, Mn, Co and Cu in different concentrations. Induction period (IP) was measured using Rancimat method (EN 14112) as the stability parameter. Based on results, several correlations were developed for assessing the storage stability in terms of IP as a function of antioxidant, metal concentration and storage time. For the purpose of design of experiment, response surface methodology (RSM) has been used. From the experiments it is found that if metal concentration is 0 then, 200 g m−3 of PY is sufficient to make biodiesel stable for 6 months. If metal (Fe) concentration is 2 g m−3 or more, then 800 g m−3 PY is sufficient to make biodiesel stable for 5.5 months. The value of storage time for Ni, Mn, Co and Cu contaminated JCB is found as 3.62, 3.24, 2.76 and 2.07 months respectively if metal and antioxidants concentration is same in all the cases. The models developed by RSM shall be highly useful for predicting the optimum antioxidant concentration to achieve maximum storage stability of JCB as well as biodiesel from other resources under the conditions set for 3 factors (antioxidant concentration, metal concentration and time). [Copyright &y& Elsevier]

Abstract: The objective of this work was to study the long term storage stability of JCB (Jatropha curcas biodiesel). For the objective JCB was mixed with PY (Pyrogallol) and different metal contaminants. JCB samples were stored for 6 months in open air exposed to sunlight. Different properties were checked with respect to time. It was found that stability of fresh JCB was not acceptable as per EN 14214. When PY was mixed with JCB, it stability increased and 200 ppm of PY was sufficient to make fresh and pure JCB stable for almost 6 months. Viscosity (n), PV (peroxide value) and AV (acid value) increased with respect to time. Unsaturated fatty acid composition was also checked with respect to time. From the experiment it was clear that as oxidation deterioration advanced, linoleic and linolenic acid methyl esters decreased and the fraction of oleic acid methyl became relatively high with respect to storage time. [Copyright &y& Elsevier]

Abstract: The present paper deals with the study on the effect of metal contaminants on the oxidation stability of Jatropha curcas biodiesel (JCB). Taking pyrogallol as the most effective antioxidant based on the earlier work of the authors, JCB was mixed with different transition metals – Fe, Ni, Mn, Co and Cu in different concentrations. Induction period (IP) was measured using Rancimat method (EN 14112). Based on results, several correlations are developed for assessing the oxidation stability in terms of IP as a function of antioxidant and metal concentration. A comparison between the experimental IP values and those predicted by the correlation shows that about 95% of the predicted data points lie within ±10% deviation lines of the experimental results. This is the first study of its kind being reported showing the relationship of IP with antioxidant concentration and metal contaminants. The correlations developed can be used to predict the amount of antioxidants required to stabilize the JCB. [Copyright &y& Elsevier]

Abstract: In the present study we have developed a new method for determining thermal pressure in case of MgO using the Kushwah pressure–volume equation along different isotherms at selected temperatures up to 1800 K. The results obtained down to a compression, V/V 0 = 0.6, present close agreement with the values determined from the Stacey reciprocal K-primed equation. The present method is based on the idea of using equations of state for variations of pressure with volume to represent variations of pressure with temperature in order to determine values of thermal pressure, which is defined as the pressure that would prevent volume thermal expansion. It has been found that the thermal pressure for MgO depends on temperature as well as compression. [Copyright &y& Elsevier]

Abstract: The vegetable oil, fats and their biodiesel suffer with the drawback of deterioration of its quality during long term storage unlike petroleum diesel due to large number of environmental and other factors making the fuel stability and quality questionable. There are various types of stabilities like oxidation, storage and thermal, playing key roles in making the fuel unstable. The present paper is an attempt to review the work done so far on the thermal stability of biodiesel and their blends with diesel under different conditions. The mechanism of thermal deterioration of vegetable oils, various methods of stability measurement including a new proposed method based on Karl Fischer coulometer, an alternative to conventional Rancimat test has been discussed. No correlations have been found in the literature among the results of various methods used. The effect of antioxidants on the stability parameters has also been discussed. TGA/DTA has been found as an effective method to check the deterioration of oil with respect to temperature using activation energy and order of reaction as the parameter to monitor the deterioration of oil. [Copyright &y& Elsevier]

Abstract: Energy plays significant role in the development of a nation. The conventional sources, though exhausting and not environment friendly are being increasingly used. Looking at limited supplies and various environment problems associated with its uses, renewable energy sources are getting attention. Municipal solid waste [MSW] is getting importance in recent years. Having fewer disposal problems is being considered as valuable bio-energy resources. The MSW management involves collection, transportation, handling and conversion to energy by biological and thermal routes. The present paper reports the results of physical, proximate and TGA/DTA analysis, used to select the most appropriate method of energy conversion. Based on the energy potential available, the feasibility of energy conversion through biogas production using available waste has been carried out. The CDM benefits have also been considered. The cost of generation with and without CDM benefits is Rs. 1.36/- and Rs. 1.41/- per kWh respectively as compared to cost of energy from grid [Rs. 3.50/- per kWh]. Therefore power generation from MSW of Haridwar city using biomethanation conversion technology is feasible. [Copyright &y& Elsevier]

Abstract: In view of the fast depletion of fossil fuel, the search for alternative fuels has become inevitable, looking at huge demand of diesel for transportation sector, captive power generation and agricultural sector, the biodiesel is being viewed a substitute of diesel. The vegetable oils, fats, grease are the source of feedstocks for the production of biodiesel. Significant work has been reported on the kinetics of transesterification of edible vegetable oils but little work is reported on non-edible oils. Out of various non-edible oil resources, Jatropha curcas oil (JCO) is considered as future feedstocks for biodiesel production in India and limited work is reported on the kinetics of transesterification of high FFA containing oil. The present study reports a review of kinetics of biodiesel production. The paper also reveals the results of kinetics study of two-step acid–base catalyzed transesterification process carried out at pre-determined optimum temperature of 65 and 50°C for esterification and transesterification process, respectively, under the optimum condition of methanol to oil ratio of 3:7 (v/v), catalyst concentration 1% (w/w) for H2SO4 and NaOH and 400rpm of stirring. The yield of methyl ester (ME) has been used to study the effect of different parameters. The maximum yield of 21.2% of ME during esterification and 90.1% from transesterification of pretreated JCO has been obtained. This is the first study of its kind dealing with simplified kinetics of two-step acid–base catalyzed transesterification process carried at optimum temperature of both the steps which took about 6h for complete conversion of TG to ME. [Copyright &y& Elsevier]

Abstract: Out of various non-edible oil resources, Jatropha curcas oil (JCO) is considered as future feedstock for biodiesel production in India. Limited work is reported on the kinetics of transesterification of high free fatty acids containing oil. The present study reports the results of kinetic study of two-step acid base catalyzed transesterification process carried out at an optimum temperature of 65 °C and 50 °C for esterification and transesterification respectively under the optimum methanol to oil ratio of 3:7 (v/v), catalyst concentration 1% (w/w) for H2SO4 and NaOH. The yield of methyl ester (ME) has been used to study the effect of different parameters. The results indicate that both esterification and transesterification reaction are of first order with reaction rate constant of 0.0031min−1 and 0.008min−1 respectively. The maximum yield of 21.2% of ME during esterification and 90.1% from transesterification of pretreated JCO has been obtained. [Copyright &y& Elsevier]

Abstract: The vegetable oil, fats and their biodiesel suffer with the drawback of deterioration of its quality when it is in contact with oxygen unlike petroleum diesel. There are various types of stabilities like oxidation, storage and thermal, playing key roles in making the fuel unstable. The present paper is an attempt to review all type of stability measuring test methods to find out the best method for stability measurement. From the review it is found that there are several methods to measure the stability of biodiesel but two test methods emerges the most likely choice for the purpose of measurement of oxidation stability of biodiesel. These are ASTM 2274 and 743 Rancimat test. A comparison between these two shows that these may be used alternatively. Most commonly used methods to investigate the thermal stability are Rancimat test, ASTM D 6408-08, D 5304-06 and TGA/DTA. Rancimat test has been suggested as an important method to measure the thermal stability of oils, fats and biodiesel fuels. [Copyright &y& Elsevier]

Abstract: The increasing industrialization and modernization of the world has to a steep rise for the demand of petroleum products. Economic development in developing countries has led to huge increase in the energy demand. In India, the energy demand is increasing at a rate of 6.5% per annum. The crude oil demand of the country is met by import of about 80%. Thus the energy security has become a key issue for the nation as a whole. Petroleum-based fuels are limited. The finite reserves are highly concentrated in certain regions of the world. Therefore, those countries not having these reserves are facing foreign exchange crises, mainly due to the import of crude oil. Hence it is necessary to look forward for alternative fuels, which can be produced from feedstocks available within the country. Biodiesel, an ecofriendly and renewable fuel substitute for diesel has been getting the attention of researchers/scientists of all over the world. The R & D has indicated that up to B20, there is no need of modification and little work is available related to suitability and sustainability of biodiesel production from Jatropha as non-edible oil sources. In addition, the use of vegetable oil as fuel is less polluting than petroleum fuels. The basic problem with biodiesel is that it is more prone to oxidation resulting in the increase in viscosity of biodiesel with respect to time which in turn leads to piston sticking, gum formation and fuel atomization problems. The report is an attempt to present the prevailing fossil fuel scenario with respect to petroleum diesel, fuel properties of biodiesel resources for biodiesel production, processes for its production, purification, etc. Lastly, an introduction of stability of biodiesel will also be presented. [Copyright &y& Elsevier]

Abstract: Biodiesel consists of long chain fatty acid esters derived from feed stocks such as vegetable oils, animal fats and used frying oil, etc. which may contain more or less unsaturated fatty acids which are prone to oxidation accelerated by exposure to air during storage and at high temperature may yield polymerized compounds. Auto oxidation of biodiesel can cause degradation of fuel quality by affecting the stability parameters. Biodiesel stability includes oxidation, storage and thermal stability. Oxidation instability can led to the formation of oxidation products like aldehydes, alcohols, shorter chain carboxylic acids, insolubles, gum and sediment in the biodiesel. Thermal instability is concerned with the increased rate of oxidation at higher temperature which in turn, increases the weight of oil and fat due to the formation of insolubles. Storage stability is the ability of liquid fuel to resist change in its physical and chemical characteristics brought about by its interaction with its environment and may be affected by interaction with contaminants, light, factors causing sediment formation, changes in color and other changes that reduce the clarity of the fuel. These fuel instabilities give rise to formation of undesirable substances in biodiesel and its blends beyond acceptable quantities as per specifications and when such fuel is used in engine, it impairs the engine performance due to fuel filter plugging, injector fouling, deposit formation in engine combustion chamber and various components of the fuel system. The present review attempts to cover the different types of fuel stabilities, mechanism of occurrence and correlations/equations developed to investigate the impact of various stability parameters on the stability of the fuel. A review of the use of different types of natural and synthetic antioxidants has also been presented which indicates that natural antioxidants, being very sensitive to biodiesel production techniques and the distillation processes have varying impacts on fuel stability and available literature is very much scarce. The work on the use of synthetic antioxidants on the stability of biodiesel (both distilled and undistilled) from various resources has indicated that out of various 8 synthetic antioxidants studied so far only 3 antioxidants have been found to increase the fuel stability significantly. However, effectiveness of these antioxidants is in the order of TBHQ>PY>PG. [Copyright &y& Elsevier]

Abstract: Energy is supplied in the form of electricity, heat or fuels and an energy supply system must guarantee sustainable energy supplies, production and distribution of energy. Such system based on renewable energy can be utilized as integrated renewable energy system (IRES), which can satisfy the energy needs of an area in appropriate and sustainable manner. For renewable energy based rural electrification of remote areas, the IRES can be modeled and optimized for meeting the energy needs. For the purpose, the Jaunpur block of Uttaranchal state of India has been selected as remote area. On the basis of field data, the resource potential and energy demand has been estimated. The total load is 808MWh/yr and total available resources are 807MWh/yr, whereas %age contribution of each resources are MHP 15.88% (128166), solar 2.77% (22363), wind 1.89% (15251) and biomass energy 79.46% (641384) kWh/yr. The model has been optimized using LINDO software 6.10 version. The results indicated that the optimized model has been found to the best choice for meeting the energy needs of the area. Renewable energy sources can contribute to the total energy demands as 16.81% (115465), solar 2.27% (15588), wind 1.78% (12201) and biomass energy 79.14% (543546) kWh/yr for the fulfillment of 687 MWh/yr at the 15% reduced level of 808 MWh/yr load. The results further indicated that optimized IRES can provide a feasible solution in terms of energy fulfillments in the range of EPDF from 1.0 to 0.75 because below 0.75 EPDF (0.50–0.25) the deficit start and so that model becomes non-feasible solution. The EPDF is electric power delivery factor and also called optimizing power factor and is maximum equal to 1. The paper reports the results of optimization of IRES models of the study area of Zone 4 of Jaunpur block of Uttaranchal state. [Copyright &y& Elsevier]

Abstract: This paper presents the transient behavior of a three-phase star connected self-excited induction generator (SEIG) using three capacitors connected in series and parallel with a single-phase load. The voltage regulation of this generator is very small due to the effect of three capacitors. The dynamic model of the above generator has been developed based on stationary reference frame d–q-axes theory incorporating the effect of cross-saturation. The steady-state model of the scheme has also been developed. The simulated results of both the transient analysis for the different dynamic conditions, such as initiation of self-excitation, load perturbation and short-circuit and the steady-state analysis are compared with the experimental results. Both the simulated and experimental results are in close agreement with each other. [Copyright &y& Elsevier]

Abstract: The world is confronted with the twin crises of fossil fuel depletion and environmental degradation. The indiscriminate extraction and consumption of fossil fuels have led to a reduction in petroleum reserves. Alternative fuels, energy conservation and management, energy efficiency and environmental protection have become important in recent years. The increasing import bill has necessitated the search for liquid fuels as an alternative to diesel, which is being used in large quantities in transport, agriculture, industrial, commercial and domestic sectors. Biodiesel obtained from vegetable oils has been considered a promising option. In this paper, an attempt has been made to review the work done on biodiesel production and utilization, resources available, process(es) developed/being developed, performance in existing engines, environmental considerations, the economic aspect, and advantages in and barriers to the use of biodiesel. [Copyright &y& Elsevier]

Abstract: Unified analyses for equations of state of MgO recently presented by several workers in order to obtain a solution for pressure-scale problems in high experiments make use of a new functional form for volume dependence of the Grüneisen parameter. In the present study we point out that this formulation is not consistent with variation of the third order Grüneisen parameter with the change in pressure. We have emphasized that the Stacey–Davis formulation for the volume dependence of the Grüneisen parameter is more appropriate than the other functional form used in the recent literature. The results have been obtained and reported for the volume dependence of the Grüneisen parameter and its higher order derivatives. [Copyright &y& Elsevier]

Freshwater bodies are found as significant sources of greenhouse gas to the atmosphere, but their quantitative significance is not yet clear. The rapid increase in hydropower dams and associated emissions has received much attention from hydropower industries, environmentalists, and policymakers from across the globe. The tropical/subtropical eco-regions are, particularly, considered as hotspots from greenhouse gas production point of view as the emitted gases are playing a critical role in climate change. The present paper reviews the uncertainty and limitations of greenhouse gas measurement from Chinese freshwater bodies based on available data. Literature reported that carbon dioxide emission from Chinese lakes falls in the range of 0.01–2.16 μmol m−2s−1 except for Poyang Lake. The CO 2 emission from Chinese hydropower reservoirs is estimated as 0.15–1.11, while for rivers, it is 0.44–4.12 μmol m−2s−1. The methane and nitrous oxide emissions are, however, found less than carbon dioxide emission. The CO 2 emission falls in the range of −0.17–0.54 and 1.08–1.70, respectively higher than global lakes and rivers, while the global reservoirs have emission in the range of −0.17–2.98 μmol m−2s−1. The paper also reports the challenges in the estimation and prediction of greenhouse gas emissions from hydropower reservoirs along with suggested mitigation measures. Image 10945 • GHG emissions have been limited by data availability and inconsistencies in methodological approach. • Investigate uncertainty and limitation of GHG measurement. • Literature reveals CO 2 emission from Chinese rivers is twice than lakes and four times than hydropower reservoirs. • CH 4 and N 2 O emissions are however found less than CO 2 emission. • Suggested mitigation measures to minimize the impact of GHG on climate change. [ABSTRACT FROM AUTHOR]