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Currently, innovations on eco-friendly, sustainability and energy-efficient technology are focused worldwide. This concept has diverted the attention of researchers to implement new natural products in many industries. The handiness and readiness of natural fibers are the main motivation for evolving new attention in sustainable development. Research gained momentum in developing novel natural fiber-reinforced materials in spite of its limitations, due to the ecological, environmental and health concerns raised by synthetic fibers. Huge amounts of agro-wastes with potential fiber contents are being discarded from many industries and are to be explored to meet the increasing demand for composite industries, which in turn helps to reduce deforestation as well as favors an effective waste management technique promoting healthier environment. The present study delivers a sound knowledge on availability of discarded fruit wastes and broad characterization of two industrial cast of areca and tamarind fruit fibers for its viability as a credible reinforcement in composites made of polymer matrix. The attained results authorize the potential of areca and tamarind fibers extracted from discarded fruit waste as a probable reinforcement in polymer composites for lightweight and domestic applications. [ABSTRACT FROM AUTHOR]

Highlights • Anatomical, thermal and tensile properties of Coccinia grandis fiber (CGF) studied. • High cellulose content (63.22%) of CGF provides good mechanical strength. • XRD and FTIR analyses exhibit the presence of I β cellulose in CGF. • TGA established the thermal stability to withstand polymerization temperature. Abstract The anatomical, physico-chemical, mechanical, thermal and surface characteristics of Coccinia grandis fiber (CGF) were studied for a potential substitute to the harmful synthetic fibers. The anatomical analysis of Coccinia grandis stem reveals the presence of high strength xylem fibers. Polarized light microscopy and scanning electron microscopy of CGF shows a hierarchical cell structure composed of a primary and a secondary cell wall, cell lumen and the middle lamellae. The average cross-sectional area and density of the CGF were 0.0111 mm2 and 1.5175 ± 0.005 g/cm3 respectively. The x-ray diffraction and Fourier transform infrared analyses of the fiber indicates the presence of cellulose I β with a crystallinity index of 46.09%. The mean Young's modulus and tensile strength of the CGF were 124 GPa and 775 MPa respectively, which is sufficient enough for the reinforcement in polymer composites. The thermogravimetric analysis confirms the thermal stability of CGF up to 250 °C, which is well within the polymerization process temperature. [ABSTRACT FROM AUTHOR]

Environmental degradation and its effects on human health due to unprecedented use of synthetic fibers, have been heavily felt by the fabricating workers and by the common people in general. The search to develop high-performance materials using environmental friendly natural fibers, is to be encouraged and needs comprehensive characterization. In this paper, discarded and polluting agro waste from food processing industry, known as Tamarind Fruit Fiber (TFF) is tested for its potentiality as a reinforcement in polymer composite. The extracted fibers are subjected to anatomical, physical, mechanical, morphological, thermal and chemical examination. The low density (1.27 g/cm3) provides high strength (1137-1360 MPa), better thermal stability (238 °C) and superior bonding characteristics revealed by standard investigations promotes TFF as a promising natural fiber reinforcement for many composite applications. Low cost and competent performance can be achieved with this natural fiber when reinforced in polymer matrix. [ABSTRACT FROM AUTHOR]

Environmental degradation and its effects on human health due to unprecedented use of synthetic fibers, have been heavily felt by the fabricating workers and by the common people in general. The search to develop high-performance materials using environmental friendly natural fibers, is to be encouraged and needs comprehensive characterization. In this paper, discarded and polluting agro waste from food processing industry, known as Tamarind Fruit Fiber (TFF) is tested for its potentiality as a reinforcement in polymer composite. The extracted fibers are subjected to anatomical, physical, mechanical, morphological, thermal and chemical examination. The low density (1.27 g/cm3) provides high strength (1137–1360 MPa), better thermal stability (238 °C) and superior bonding characteristics revealed by standard investigations promotes TFF as a promising natural fiber reinforcement for many composite applications. Low cost and competent performance can be achieved with this natural fiber when reinforced in polymer matrix. [ABSTRACT FROM AUTHOR]

The unprecedented use of fossil fuels necessitates the research community to find clean, safe, renewable and sustainable energy source. One such promising source is microalgal biofuel, which can mitigate the environmental concerns and energy crisis due to its closed carbon cycle. Selection of proper strain and optimization of the culture conditions to maximize the lipid productivity is very important for successful economical biodiesel conversion process. One such robust halophilic species identified was Aphanothece halophytica with rich lipid productivity. They were cultivated in different media and optimized on lab scale as well as in large scale using raceway ponds to produce sufficient biomass for algal oil extraction. The biodiesel conversion process parameters were then optimized by multi-variant response surface methodology (RSM). The free fatty acid (FFA) content of the raw algal oil was only 0.51% which enables direct conversion by transesterification. Eco-friendly, natural white clam shell was calcinated to obtain CaO, which was recovered and reused for three times effectively. The maximum biodiesel yield of around 99 vol% was obtained for the oil/methanol ratio of 0.32(v/v) using calcinated CaO for 6 wt% of raw feed while stirring at 400 rpm at a temperature of 70 °C for 85 min. The GC–MS analysis of the algal biodiesel confirmed the presence of saturated and unsaturated fatty acids in balanced proportion to provide better oxidation stability and good combustion characteristics. Other biodiesel properties were analyzed and found to be within the standards specified by EN and ASTM for automotive application without any engine modification. [ABSTRACT FROM AUTHOR]

The environmental and culture conditions of a potential microalgae Euglena sanguinea were optimized for maximizing the biomass productivity. It was found that the organic macronutrient from poultry litter and organic micronutrient of seaweed extract are very effective to enhance the lipid production. Complementing, these organic nutrients with commercial NPK fertilizer, boost up the lipid productivity by 30.9% in comparison with the established standard Euglena medium. The fatty acid profile of the extracted oil by GC–MS reveals its conformity with commercial diesel. [ABSTRACT FROM AUTHOR]

Algal biofuels have caught worldwide attention, due to the success of first and second generation biofuels on combing environmental concerns in spite of many challenges. Microalgae are the potential and sustainable fuel source with carbon neutrality, where selection of promising strain is crucial for effective biofuel generation. Euglena sanguinea one such robust freshwater species with high lipid productivity was explored on laboratory scale as well as in mass scale in raceway pond. The extracted oil’s fatty acid value was only 3.8 mg KOH g −1 and had 93% triglycerides. Acid value was reduced to ∼0.3 mg KOH g −1 by esterification and the optimized parameters obtained were: methanol/oil ratio: 0.36, H 2 SO 4 : 10 vol.%, time: 42 min. In the subsequent transesterification process natural, recoverable and eco-friendly white mussel shell was used. Maximum yield of ∼98% was obtained at 6 wt.% of calcinated CaO for the reaction time of 80 min at 0.35 methanol/oil ratio. The GC-MS analysis of the algal biodiesel showed the presence of saturated fatty acids: C16:0, C18:0, C22:0, C24:0 and monounsaturated fatty acids C18:1 at appropriate level to provide better oxidation stability and combustion properties to use it for automotive application without any major engine modifications. [ABSTRACT FROM AUTHOR]

Diffusion bonding is a pressure welding technique to establish bonds by inter diffusion of atoms. Bonding characteristics were generated by varying the significant process conditions such as the bonding temperature, the pressing load and the duration of pressure while bonding the aluminium alloys AA5083 and AA7075. Deriving analytical correlation with the process variables to weld strength is quite involved due to the non-linear dependency of the process variables with the mechanical strength of the joints. An arbitrary function approximation mechanism, the artificial neural network (ANN) is therefore employed to develop the models for predicting the mechanical properties of the bonded joints. Back propagation technique, which alters the network weights to minimize the mean square error was used to develop the ANN models. The models were tested, validated and found to be satisfactory with good prediction accuracy. [ABSTRACT FROM AUTHOR]

Finding new biofuel resources and consolidating the preliminary findings on biodiesel extraction are important to optimize mass production. In this paper biodiesel is extracted from non-edible, abundantly available, potential, and viable neem oil. Design of Experiment is employed to optimize the process parameters of the two-stage esterification process. Methanol has the greatest influence in both stages, followed by choice of catalyst and duration. Standard test procedures were followed to ensure the adequacy of the fuel properties, and the results are encouraging in regard to using neem oil as a potentially renewable and sustainable biodiesel source. [ABSTRACT FROM PUBLISHER]

The dwindling fossil fuel resources and the environmental degradation have spurred research interest to find better renewable alternative energy sources. Biodiesel is one such viable promising alternative fuel, which can be extracted from various renewable vegetable oils. In the present study, biodiesel extracted from neem oil is characterized for engine performance and emission analysis is done at various compression ratios (CR) and fuel blends. The brake thermal efficiency (BTE) of the blend B20 is considerably higher than that of diesel at CR 18, 20, and 22. The specific fuel consumption (SFC) increases with diesel blends due to a higher calorific value of diesel in comparison with biodiesel. All the biodiesel blends had lower carbon monoxide (CO) emissions compared with diesel, which indicates better combustion due to the presence of inherent oxygen. At lower CRs, the in-cylinder temperature is lower, which in turn reduces the nitrogen oxide (NOX) emission. The overall engine performance is optimum at CR of 18 with the NB20 fuel blend. [ABSTRACT FROM AUTHOR]

Natural fibers from bio-renewable sources have the potential to be used as an alternate reinforcement for the perilous synthetic fibers. The hazards of prolong exposure to such fibers are quite serious, which demands scientific intervention. Natural fibers, like the one investigated – Cissus quadrangularis stem fiber (CQSF), have proven thermomechanical properties for polymer composite reinforcement. Enhancing fiber–matrix bonding through chemical treatments such as mercerization and deposition of cotton linters-based microcrystalline cellulose powder on fiber surface are comprehensively investigated. The mechanical properties of treated fiber composites reveal good bonding features through scanning electron microscopy analysis, which are further substantiated by the evaluation of mechanical property. In particular, 5 wt.% cellulose powder-treated CQSF/polyester composites showed distinguishable enrichment in mechanical and water absorption characteristics. [ABSTRACT FROM AUTHOR]

Natural fibers are being used as reinforcing materials for polymer composites due to their eco-friendly properties.Arecafruit husk fiber (AFHF) is one such fiber; it is currently discarded waste from the tobacco industry, but has huge potential. It is light in weight with a perforated surface that enables good bonding with a polymer matrix. In this study, comprehensive characterization of physical, chemical, thermal, mechanical, and microstructural properties was carried out on the fiber and the composite made with that fiber to optimize the fiber content. The optimum fiber content is found to be 40 wt.%, whereas beyond that, fiber pull-out and debonding reduces the load-bearing capacity of the composite. The specific properties of AFHF polymer composite are even higher than that of the popular E-glass fiber composite, which positions AFHF composite as an alternative structural material. [ABSTRACT FROM AUTHOR]

Unearthing new sustainable and economically viable sources for biofuel production which do not affect the environment is a dire need of the hour. Microalgae is one such promising source due to its high lipid content, productivity, and carbon neutrality. Identification of appropriate strain and process optimization decides the biomass productivity, nutrient value, and oil content which are the major factors for commercialization. In the present work, mass cultivation of halophilic Aphanothece halophytica in raceway ponds was optimized by using organic and inorganic nutrients by using design of experiments. Organic flocculant, neem plus was successfully adapted for harvesting the biomass and oil extraction was done with solvent methodology. A maximum lipid yield of 29.3% was obtained on wet basis, when the reaction temperature, reaction time, biomass-to-solvent ratio and mixing intensity were kept at 68 ºC, 190 min, 9:1, and 300 rpm respectively. Similarly, on dry basis, a lipid yield of 27.5% was reported when the reaction temperature, reaction time, biomass-to-solvent ratio and mixing intensity were maintained at 68 ºC, 190 min, 12:1, and 300 rpm respectively. GC–MS analysis of the lipid was done to appropriate the combination of fatty acid for enhancing the biofuel production. [ABSTRACT FROM AUTHOR]

Polymer composite has contributed tremendously for energy efficient technologies in automotive and aero industries. Environmental and health concerns related to the carcinogenic nature of artificial fiber in polymer composite needs a retrofit. Eco friendly natural cellulosic fiber extract from the stem of Cissus quadrangularis plant is extensively characterized to consider as a viable alternative for man-made hazardous fibers. Anatomical study, chemical analysis, physical analysis, FTIR, XRD, SEM analysis and thermo gravimetric analysis were done to establish the certainty of using them as reinforcement fiber. Its light weight and the presence of high cellulose content (82.73%) with very little wax (0.18%) provide high specific strength and good bonding properties in composite manufacturing. The flaky honeycomb outer surface revealed through electron microscopy contributes for high modulus in CQ stem fiber and thermo gravimetric analysis ensures thermal stability up to 270 °C, which is within the polymerization process temperature. [ABSTRACT FROM AUTHOR]

Abstract: The analysis on reliability aspects of wind power finds more significance as compared to that in conventional power generation systems. In spite of the intermittent and variable nature of wind energy, it can be usefully tapped to generate electrical power for meeting part of the energy demand of the population. The present paper undertakes an analysis on the reliable aspects of wind energy conversion system and applies to seven wind farms in Muppandal region in India. For the purpose of analysis, two reliability indices are used; one is coined as the period during which the expected wind energy is not supplied and the other one is the loss of load expectation index which analyzes the degree of matching of wind farm power generation with the load model. The study also investigates the effect of increasing the hub height of wind energy conversion systems. [ABSTRACT FROM AUTHOR]

Abstract: This paper attempts to assess the adequacy of wind power generation systems using the data collected from seven wind farms in Muppandal, Tamilnadu (India) with a total capacity of 37 MW. A Monte Carlo model simulation is incorporated in the algorithm to obtain the hourly power output of wind farms, which also takes into account the unavailability of wind turbines. A typical load demand profile is used to examine the chronological hourly wind power generation for each month. The reliability index of LOLE (loss of load expectation) is used to estimate the reliable contribution of wind farm power generation. [ABSTRACT FROM AUTHOR]

Abstract: The influence of structural and microstructural properties on the compressive properties of closed-cell aluminum foam is investigated. The presence of brittle intermetallic, Al13Fe4 in the cell wall matrix modifies the compression behavior in the plateau region, where decrease in stress values is observed due to the brittle nature of cell wall. However, particles of higher aspect ratio in cell wall increase the stability of foam. Gibson and Ashby model results showed more disparity with the experimental results owing to uncertainty in determining the value of φ at higher density, which is the fraction of solid contained in the cell edges. Multilinear regression model for the prediction of mechanical and energy absorption properties is developed by considering the contribution of pore diameter and cell anisotropy ratio along with relative density of foam. In this system it is found that the cell edge effects are more significant compared to the cell face effects. [Copyright &y& Elsevier]

Abstract: The design of artificial neural network (ANN) is motivated by analogy of highly complex, non-linear and parallel computing power of the brain. Once a neural network is significantly trained it can predict the output results in the same knowledge domain. In the present work, ANN models are developed for the simulation of compressive properties of closed-cell aluminum foam: plateau stress, Young’s modulus and energy absorption capacity. The input variables for these models are relative density, average pore diameter and cell anisotropy ratio. Database of these properties are the results of the compression tests carried out on aluminum foams at a constant strain rate of 1×10−3 s−1. The prediction accuracy of all the three models is found to be satisfactory. This work has shown the excellent capability of artificial neural network approach for the simulation of the compressive properties of closed-cell aluminum foam. [Copyright &y& Elsevier]

The evolution of closed-cell aluminum foam synthesized by titanium hydride decomposition is explained on the basis of foam stability and gravity-induced drainage of liquid. While the average pore size progressively increases due to TiH2 decomposition, the aspect ratio shows a sudden transition during the holding period. The sudden increase in aspect ratio with the major axis transverse to the growth direction is explained on the basis of the loss of elasticity of the cell wall due to drainage and subsequent cell wall collapse due to the weight of the overlying foam. Intermetallic particles with a high aspect ratio distributed in the cell wall matrix significantly improve the stability of the liquid foam. It is demonstrated that by varying a single process parameter, such as the holding time, foams with a wide range of structural parameters are accessed. The Gibson and Ashby model showed good correlation with the plateau stress and Young’s modulus results presented in this work. [ABSTRACT FROM AUTHOR]

Dry sliding friction and wear behavior, hardness, and thermogravimetric analysis (TGA) of Cissus quadrangularis stem fiber (CQSF)/epoxy resin composite, reinforced with red mud particulate filler were done. The hardness of the material increased by adding red mud filler. Thermogravimetric analysis (TGA) reveals that the maximum char yield obtained at 10 wt.% red mud particulate-filled with CQSF/epoxy composite. The optimization of dry sliding friction and wear behavior was done by response surface methodology (RSM) based on pin-on-disc wear test to determine the specific wear rate (SWR) and coefficient of friction (COF) of the materials. The experimental design was created with four input parameters at three different levels using full factorial central composite design (CCD). The minimum SWR was achieved at 5.93 wt.% red mud addition irrespective of other parameters, was obtained by RSM optimization technique. The scanning electron microscopy (SEM) images of the worn out surfaces substantiate the optimized results of wear properties. [ABSTRACT FROM AUTHOR]

In recent years, basalt fiber reinforced polymer composites have gained popularity as an alternative to synthetic glass fiber reinforced polymer composites. Unidirectional 0°/90° basalt fiber-reinforced SiC micro and nano filled composites were tested for tensile, flexural, impact and hardness characteristics to determine the optimal composition. Comparing the mechanical properties of the composites reinforced various combinations of SiC micro or nano filler particles 4 wt% nano SiC filler addition exhibits superior properties. The scanning electron microscopy (SEM) images also reveals the improved interfacial interaction between the fiber mat and matrix for filler concentration up to 4 wt% SiC nanoparticles. Moreover, the wear resistance of the composites with 4 wt% SiC micro particles was better with low weight loss in wear test. The water absorption ability of the composite was low for the composites reinforced with 2 wt% SiC nanoparticles. Most of the properties of the composition with optimum filler addition are good enough for structural applications. [Display omitted] [ABSTRACT FROM AUTHOR]

Petroleum reserves are diminishing at a faster rate and the world is facing twin crisis in fossil fuel depletion and environmental degradation owing to extensive use of fossil fuel. Finding viable and sustainable alternative fuel is crucial for the world at large and especially for oil importing countries like India. In the present work, biodiesel is produced from tamanu oil, which is non-edible, plentiful, and cost effective. However, the viscosity is high which demands a two stage esterification to reduce its fatty acid content within the limits for automotive applications. Due to interactive effects among the process parameters, design of experiments is employed for optimization. It was observed that methanol and catalyst concentration are the major influencing process parameters, whereas time and temperature have insignificant role on acid value reduction and percentage of oil yield. The extracted biodiesel was tested for fuel properties with standard test procedures and found to be in compliance with ASTM standards. [ABSTRACT FROM AUTHOR]

[Display omitted] • Euglena sanguinea's potential tested for a feasible biodiesel source. • Novel reactor, designed and fabricated for oil extraction and biodiesel conversion. • Algal biodiesel tested for compatibility with existing engine without modification. • Operation parameters and fuel blend optimized based on performance and emission. Pollution is one of the major tricky issues in the world due to the negative impact of vehicle population and industrialization. Transport sector is still struggling to control the pollution in spite of making many initiatives to keep it in control. Researchers have successfully claimed that biodiesel could be a possible solution due to its closed carbon cycle. In this scenario, microalgal biodiesel has the potential resource to reduce the vehicle pollution as an alternative fuel source. In this work, microalgae cultivated in open raceway ponds in optimized composite media were harvested with low cost filters, dried and oil extracted using solvent method. Two step conversion processes was employed to convert algal oil into biodiesel using optimized process parameters. Naturally available sea shell was used as the catalyst in the transesterification process. A new comprehensive bioreactor was designed and fabricated for oil extraction, esterification, transesterification and distillation process to produce 10 l of biodiesel in a batch. The biodiesel was then tested in the internal combustion (IC) engine test rig for various blends to analyse the performance and emission at different compression ratios (CRs). The brake thermal efficiency (BTE) of 27.42% at specific fuel consumption (SFC) of 0.225 kg/kWh was obtained for B30 blend at CR of 19. The emission characteristics were also found to be low at CR 19, which is the rated CR of the engine for diesel fuel. [ABSTRACT FROM AUTHOR]