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Wear parameter optimization is critical for the successful use of materials in load-bearing applications. This study examines the optimization of various wear parameters using the Taguchi technique for the determination of the specific wear rate of alpha-manganese dioxide (α-MnO2)-epoxy nanocomposites. Four factors viz. wt.% loading of α-MnO2, sliding distance, sliding velocity, and normal load, were selected as controllable factors and a suitable L16 orthogonal array was chosen for conducting experiments. An X-ray diffractometer and field emission scanning electron microscope were used to examine phase identification, surface morphology, and chemical composition. With the addition of α-MnO2 in the epoxy, the tensile stress is decreased, while the elastic modulus is increased. The Taguchi result shows that the wear test in optimal condition is carried out with a wt.% loading of α-MnO2 of 0.5%, a sliding distance of 500 m, a sliding velocity of 1.5 m/s, and an applied normal load of 5 N. Analysis of variance shows the wt.% loading of α-MnO2 has the most influential parameter on specific wear rate with a contribution of 87.94%. The analysis also shows that the general linear model accurately describes the effect of sliding wear parameters on specific wear rates. The Monte Carlo simulated model shows that the experimental signal-to-noise ratios are consistent with the simulated model values. The confirmation test result shows that the % error between the predicted and experimental values of the specific wear rate at the optimum level combination is 4.67%. The worm surfaces of different trial runs show that the material removal process is caused by crack propagation. High-resolution scanning electron microscopic images of fractured surfaces show the formation of a stable tribo-layer at 0.5 wt.% α-MnO2 loading resulted in a significant decrease in the specific wear rate of the sample.

Engineering materials and their development are essential for a civilized society, and they have always played a key role in the industrialization of a country. The performance of materials can be increased by selecting appropriate fabrication process parameters. In this paper, the effect of fabrication processing parameters on multi-responses of lightweight material, namely, functionalized multiwalled carbon nanotubes-aluminum nanocomposite have been investigated through Taguchi-based grey relational analysis. Ethanol wt. %, milling time, compaction pressure, and sintering temperature were considered controlled parameters. Phase, surface morphology, and chemical compositions of the nanocomposite have been analyzed by X-ray diffraction, scanning electron microscopy, and energy-dispersive X-ray techniques. The scanning electron microscope images revealed that the optimal parameter combination is essential for decreasing void and crack formation during the powder metallurgy process and increasing the material performance index. Grey relational analysis was performed to evaluate optimal sample fabrication processing parameters by using grey relational grade as performance index measurement. The most influential parameter was investigated using main effect plots, interaction plots, contour plots, and analysis of variance. The results show that the optimal combination of sample fabrication parameters is A1B2C3D3. The results also show that the compaction pressure has a stronger correlation to the responses with a 46.92% contribution followed by sintering temperature. The % error between the predicted and experimental grey relational grades at the optimum-level combination is 1.83%. The Monte Carlo simulation data distribution plots show that the ranges of experimental mass density and hardness values are consistent with estimated simulated model values. Further, a regression equation has also been developed to establish the predictive model for the grey relational grade. The model analysis shows that the predictive model is adequate for evaluating grey relational grades. Therefore, this study confirms that the proposed approach can be a useful tool for improving materials’ performance.

Tribology is the study of moving surfaces, and it has a variety of effects on our lives. From an economic point of view, wear is one of the most important aspects of an industry’s viability. Parts of the machine can wear out, and they need to be replaced. This is especially important for polymer-based materials. Therefore, it is important to reduce maintenance costs and improve machine reliability in a variety of engineering applications through proper material selection. The present investigation deals with the fabrication of manganese dioxide (MnO2)/epoxy nanocomposite and investigates its tribological properties. The MnO2/epoxy nanocomposites were fabricated via a solution mixing technique. The phase identification and surface morphology of the sample was examined by X-ray diffractometer and field emission scanning electron microscope, respectively. The mass density, micro-hardness, and specific wear rate data of samples revealed that the mass density, micro-hardness, and wear resistance of the samples increased with the addition of MnO2 in the epoxy matrix. The nanocomposite sample containing 0.5 wt. % MnO2 loading in the epoxy matrix shows higher density, micro-hardness, and wear resistance compared to other samples. The result also shows that with the addition of MnO2 in the epoxy matrix, the coefficient of friction of the samples is increased. The percentage reduction in specific wear rate due to the addition of 0.5 wt. % MnO2 in neat epoxy is 68.10%, whereas the percentage increase in the coefficient of friction is 19.30%. The results of the analysis of variance show the effect of adding wt. % of MnO2 in the epoxy matrix is significant in the tribological responses. The worn surface analysis shows that the fatigue wear mode seems to be the dominating mode of wear for all samples as compared to the other modes of wear. The properties of MnO2/epoxy nanocomposite data revealed that the developed material may be used in the automotive industry as a structural material, fabrication of snow sled, ball bearing housing, or plastic gear materials with adequate lubrication.

This article presents the mechanical, physical, and tribological properties of the boron carbide (B4C) reinforced epoxy matrix composites (BEMCs). The BEMC samples were prepared with various B4C concentration of 0%, 1%, 2%, 3%, and 5%. B4C particles were treated with a silane coupling agent to ensure efficient adhesion with epoxy. The influence of a range of parameters (particle loading, sliding speed, sliding distance, and normal load) on the wear and friction behavior of BEMCs were evaluated by conducting wear tests under dry sliding conditions on a pin-on-disc wear test set-up. The addition of B4C to the epoxy polymer improved the wear resistance of the composites. Maximum wear resistance and coefficient of friction were observed for the composite with the highest percentage of B4C (5%). The specific wear rate was reduced on increasing load and sliding distance and increased with the sliding velocity. Mechanical properties including compression strength, flexural strength, and impact energy, along with physical properties such as density and hardness, were also evaluated. B4C particles improved the hardness, density, flexural and compression strength, and impact resistance of the composites. Scanning electron microscope (SEM) analysis of the worn-out surfaces and flexural fractured surfaces was carried out to predict the possible wear and fracture mechanisms. Micro-ploughing, abrasion, and adhesion were the wear mechanisms in BEMCs. Under the flexural loads, particulate de-bonding, pull-out, and brittle fracture of the matrix were the governing failure mechanisms.

India is among the largest producers of sugarcane in the world. Sugarcane bagasse (SCB) has been used in different applications in the area of sugar and its products, biomedical sciences, biotechno...

Alumnium alloy LM 25 based composites reinforced with boron carbide at different weight fractions of 4%, 8%, and 12% were fabricated by stir casting technique. The microstructures and morphology of the fabricated composites were studied by scanning electron microscopy and energy dispersive spectroscopy. Elemental mapping of all fabricated composites were done to demonstrate the elements present in the matrix and fabricated composites. The results of microstructural analyses reveal homogenous dispersion of reinforcement particles in the matrix with some little amount of clustering found in composites reinforced with 12% wt. of boron carbide. The mechanical characterization is done for both alloy LM 25 and all fabricated composites based on hardness and tensile strength. The hardness increased from 13.6% to 21.31% and tensile strength 6.4% to 22.8% as reinforcement percentage of boron carbide particles increased from 0% to 12% wt. A fractured surface mapping was also done for all composites.

The objective of this study was to develop a natural fiber-based composite with fibers extracted through a simple technique called a steam explosion. These environment friendly materials having deterioration rate greater than that of the other polymer-based materials commonly used in manufacturing industries. During this study, the cellulose nanofibers were extracted from a hemp fiber with the help of steam explosion technique. To confirm its suitably for bio-based composites structure implementations, the characteristic features and morphological properties were meticulously studied. The chemical characterization of Hemp fiber material exhibited a rise in cellulose content from 64% to 95%, due to bleach, alkali and acid therapies. Scientific evidence confirms that non-cellulosic compounds extraction such as lignin and hemicellulose that occur in acid, steam explosion and bleaching treatment, as observed in chemical properties during pre and post chemical fiber therapy. Scanning electron microscopy studies indicates that a decrease in the fiber-diameter aspect ratio and the percentage yield of nano-fiber removed by such a procedure is found to be very high compared with other conventional approaches during steam explosion with acid treatment. X-ray diffraction analysis exhibited the crystallinity of fiber contained crystalline cellulose was increased due to performed procedure. The composite developed with the reinforcement of the steam explosion process demonstrate increased mechanical properties such as hardness, tensile strength and toughness of the material used (Epoxy LY 556 and Hardener HY 951). The cellulose fiber-reinforced composites were processed after obtaining the cellulose fiber from the steam explosion process. Mechanical properties such as harness, tensile strength and toughness were significantly improved.

India is undergoing energy deficit for past two decades in power supply, both for required energy supply as well as peak load demand. The problem is intense during peak demand or in summer season and essential to plan load shedding by several plants to secure supply grid. So, now sustainability has become a discourse topic to save environment. The present environment is a sign of efficiency of building construction and industrial behavior, i.e. the way of resources used by them e.g. water consumption, energy use, emission of harmful gases and other factors. Building construction is the only sector to consume about 40% of total generated energy of India. Environment is directly and indirectly influenced by building operation and (material) construction, so now focus on applying effective material to save both environment and energy. Utilization of various bio-degradable insulation materials in building which enhance building strength, provides good human comfort, saves energy and environment. The most important aspect of this insulation material is its performance i.e. regularly provides the resistance to heat flow. It helps in reduction of energy consumption around 30–35% of energy and proportionate reduction of carbon di-oxide emission.

India is a developing country and thus has to cater to high energy demands in both rural and urban areas. Buildings and construction together account for 36% of global final energy use and 39% of energy-related carbon dioxide (CO2) emissions when upstream power generation is included. In India, the building sector consumes around 30% of the total energy. This research work is divided into two parts. The first one is the comparative evaluation of insulation materials for optimization of energy, and the other one is direct encapsulation of PCM material into the wall. The selection of building insulation materials such as EPS, XPS, PUF, GW and RW etc is based on market availability and suitability to weather conditions at building location. The Indian weather conditions have been classified into 6 different categories as per ISHRAE namely hot and dry, warm and humid, moderate, cold and cloudy, cold and sunny, and composite and similarly classified as Very Hot–Humid (1A), Dry (1B) as per ASHRAE 90.1 2007. Five locations of India with different climatic conditions have been chosen covering all Indian climatic zones which are Delhi (composite), Mumbai (Warm & Humid), Ahmedabad (Hot & Dry), Bangalore (Composite), and Srinagar (Cold). Selected types of insulation materials have been tested for thermal load performance of the building envelope in each of the above weather conditions including life cycle cost (LCC) analysis for 20 year period, carried out to select the best alternative amongst the selected insulation materials for each of the weather conditions. The parameters for the selection of insulation material are based not only on saving energy but also on protecting the environment from harmful gases. In Delhi state, The best suitable insulation material is RW since its payback is 1.08 years with maximum energy saving of 17.82%. In the case of Ahmedabad, GW gives maximum energy saving with optimum thickness, but the payback period is much lesser for Rock Wool viz.,1.06 years. In the case of Bangalore, the suitable material is RW with the payback period of 1.84 years. For Mumbai city, RW is the optimum material with a payback period of 2.02 years.

Plant base cellulose nanofibers with diameter 20–50 nm are obtained by Agave gigantea through the steam explosion method. These nanofibers used as a reinforcement to making composites at different percentages (10%, 15%, and 20%) with epoxy LY556 & hardener HY951 used as a matrix at a 10:1 ratio. Thermoset polymer is used as a matrix although it has a great strength-to-weight ratio, and performance, and good thermal properties. Preparation of composite used hand-lay-up method with random orientation of fibers, examining the mechanical properties of nanofiber-reinforced polymer matrix composites like tensile testing, impact testing, and hardness of the composites. The percentage of nanofibers has greatly influenced the mechanical properties of the material. The significant enhancement of mechanical characteristics was observed as the result of addition of nanofibers as a reinforcement in composites. Finding the percentage of absorption of moisture for the different samples at the same period and the rate of water absorption depend on the percentage of fiber used in the composite. It is directly proportional to the percentage of fibers and is the only the demerit when using plant base nanofiber as reinforcement.

Presence of the solar energy sources in energy combination is the fastest developing movements in all over the world to decrease the reliance on fossil fuels re-serves. Whereas, the increase in the oil prize and pollution problems has forced to develop the electric vehicle with solar energy system. This work discusses the control of solar powered induction motor drive with advanced control approach. The overall system permits good control operation of induction motor drive through advanced architecture that allows the consumption of accessible solar power at most of the time. The complete system consists of a boost converter for maximum power taken from solar energy system and to regulate the dc link volt-age, advanced rapid predictive pulse width modulated three phase inverter to control the three phase induction motor drive. The efficiency parameters of the three phase inverter are primarily dependent on the control approaches used to regulate the inverter. In this paper, the advanced rapid pulse width modulation technique is used for regulating the inverter as it can regulate the input of the induction motor according to the functions. Therefore, modelling and simulation of the solar assisted electric vehicle with induction motor has been presented with advanced control approach.

The purpose of this investigation is wear characterization of solid glass microspheres (SGM) and boron carbide (BC)-reinforced epoxy composites, under dry sliding conditions using a pin-on-disk wear test machine. Influence of parameters like sliding distance, sliding velocity, applied load and addition of fillers, on the wear rate were examined. Taguchi technique was used for the plan of experiments to conduct wear tests. To evaluate the effect of the individual parameters on the rate of wear performance of composites, analysis of variance (ANOVA) and an orthogonal array were employed. Linear regression analysis was employed for all the composites to establish an empirical relation between the various process parameters and wear. The results indicate reduction in wear of polymer on addition of particulates with the lowest wear rates observed in composites with addition of boron carbide as filler. Different fracture mechanisms were revealed by Scanning electron microscope (SEM) images of worn-out composite surfaces.

The main objective of this article is to study the complexities and nuances of exclusion of Muslims, a dominant minority group in India and Britain. It is an exploration of how Muslims, a religious minority in both India and Britain, are facing exclusion in different spheres of life, namely socio-economic and physical spaces. Moreover, it also explores the process of ‘othering’ which further excludes Muslims. It aims to explore how exclusion is directly associated with religion in face of a stigmatised religious identity. Muslims in India and Britain are not one monolith community. However, their experience of exclusion in different spheres of society offers some similarities. It offers an account of the fact that Muslims stand on the periphery in social and secular spheres of life and how this is closely related to their identity.

This article is a review of the properties of boron carbide (B4C)-reinforced polymer composites. B4C have recently become attractive to researchers, engineers, and scientists as an alternative rein...

This article investigates the effect of powder metallurgy processing parameters on multi-responses: mass density and hardness of Al2O3/Cu composite based on Taguchi method coupled with Grey relational analysis. Based on Taguchi’s L18 orthogonal array, the experimental trial runs were conducted with four controllable powder processing parameters: milling time, compaction pressure, sintering temperature and holding time. The Grey relational analysis (GRA) was performed to find the optimal powder processing condition with Grey relational grade (GRG) as a measure of performance index. Analysis of variance (ANOVA), 3D surface plots and contour plots were used to express the most influential parameter that affects mass density and hardness of Al2O3/Cu composite. Confirmation tests were conducted to make sure the validity of test results. The scanning electron microscope (SEM) images show the presence of Al2O3 particle in the composite. The Energy Dispersive X-Ray (EDX) spectrum indicates the presence of chemical elements: Cu, Al, O in the composite. The results show that the optimal powder metallurgy parameter combination is A2B3C3D1. The mean Grey relational coefficient (GRC) analysis shows that the mass density was more easily influenced by factors considered compare to hardness. The mean GRG result shows that the compaction pressure has the strongest correlation to responses. The result of 3D surface plots, contour plots and ANOVA indicate that the compaction pressure has most influential parameter that affect GRG. The % contribution of parameters shows that the % contribution of compaction pressure is significant (80.22%) compare to other main effects and interaction effects. The confirmation tests revealed that the performance characteristic of Al2O3/Cu composite was improved by GRA based Taguchi technique. The Monte Carlo simulated model summery show that based on Taguchi L18 Orthogonal Array design, one can easily find the reality of what will be happening in a process. Therefore, optimization of processes parameter could be simplified by using the Grey-based Taguchi method.

Automobile sector heavily relies on burning of fossil fuels to meet its energy requirements. This continuous burning of fossil fuels generates harmful emissions which are hazardous for both environment and human being. To stare down these emissions levels, appropriate methods of emission reduction or a sustainable replacement to fossil fuels are desiderating of the current situation. An alternate solution to the stated concern is biodiesel, which is non-toxic, biodegradable, and renewable by its nature. Another advantage, where little or no modification to present compression ignition (CI) engines is boon for utilizing biodiesel. Biodiesel originates from organic matter, from animals and plants, via — a chemical process called transesterification. During the process, methyl or ethyl ester (biodiesel) are refined from animal fat or vegetable oil with other useful products like glycerin. The pure form of biodiesel, which is abbreviated as ‘BXX’- B100 (pure biodiesel), while blended with petroleum diesel in proportion are B2-2% biodiesel, B5-5% biodiesel, and B20-20% biodiesel. Biodiesel produced from plant origin like non-edible grade oil from Jatropha plant has promising potential as blending fuel. It has an economic aspect too, as blended petroleum products or pure biodiesel reduces the dependency of foreign petroleum imported by countries like India. This article is about CFD based combustion analysis of biodiesel fuel using Ansys Fluent© and matched with the combustion of diesel fuel. Parameters like the temperature of combustion at various blend ratios of B0-B100 varies from 2100 K to 1100 K are recorded through contour plots. Results are compared with diesel fuel, and an appropriate blend ratio is given for biodiesel for having for maximum efficiency and the least emission in applications.

Present work represents the preparation of metal-metal (Al-Cu) functionally graded materials (FGMs) using powder metallurgy followed by sintering. The Al-Cu FGMs are developed by fine Al powder (purity 99.9%, 200 mesh) and copper powder (purity 99.9%, 300 mesh). The proposed composition of the graded material includes multilayered composite layers of varied Cu compositions (90 wt%, 80 wt%, 70 wt%, 60 wt%, 50 wt%, 40 wt%, 30 wt%, 20 wt%, 10 wt%). Optical microscopy and SEM images, has been taken for each sample to discuss the morphological aspects to validate the developed material. Results revels the successful development of FGM in terms of micro structural observations.

Sabah Khan’s essay is an intersectional recount, of how football has been instrumental in enabling young Muslim women from a ghettoized suburb of Mumbai to engage with community and society imposed boundaries, illustrating the sports-for-development agenda. This engaging chapter serves as an illustration of the possibilities inherent in sport for enabling women, especially from disadvantaged and vulnerable communities to overcome social restrictions as well as patriarchal, gender-specific norms of dress and behaviour. The author describes her engagement with a group of women in the outskirts of Mumbai in their struggle to play, to stake claim to a public space and to participate in an activity that community and society do not view as being appropriate for women. The chapter serves to point to the many ways the study of sport and its participants may assist in the exploration of how change may occur in increments.

Functionally graded materials are tailor-made materials. In the present work, the theoretical study of Al–Cu functionally graded material through gradation laws is investigated. The properties like density, Young’s modulus, shear modulus, specific heat and thermal conductivity are taken into consideration. The gradation laws such as power law, exponential law and sigmoid law gradation laws are applied to evaluate the behavior of these parameters at varying index numbers from one to three. It has been concluded that increasing the value of power law index (n), variation in all the effective material properties (mechanical and physical) of Al–Cu FGM, changing from linear into a polynomial way. Al (material at the bottom surface) properties are becoming more predominant up-to a larger range of z/h ratio with increasing value of power law index (n). At the value of n = 1, power law and Sigmoid law both are predicting the same results which are simply the rule of mixture.

Natural fibers have been in researchers’ attention these days for their low cost, availability, ease of manufacturing and potential environment friendliness for studying their feasibility as reinforcing agents in composites. Numerous research works are being carried out across the globe to increase the thermal, tribological as well as mechanical properties of these engineered biocomposites and they have proved their potential in wide range of applications including bio-medical and bio-technological fields. This review aims to discuss the mechanical properties attained by the composite after natural fiber reinforcement and the various factors affecting the mechanical properties of the natural fiber composites (NFCs). It also focuses on the applicability of natural fibers as a substitute for synthetic fibers in large domain of application.

This research work is carried out to study the mechanical and wear behaviour of inorganic particle filled polymers. The usage of polymers especially epoxy resin is of considerable significance in the engineering field for a substantial period of time. Epoxy matrix filled with varying ratios of Solid glass microspheres (SGM) were fabricated using mechanical stirring process. The weight percentage of SGM were varied from 0 – 30, with a step size of 5wt%. Effect of weight percentage of SGM particles on bending strength, compression strength and compression modulus of the composites was evaluated. The Wear resistance of the composites against En-32 steel disk, was evaluated in terms of mass loss for various ratios of SGM using pin-on-disk test rig. Besides these, density of the composites was also evaluated. Mechanical and wear properties of the composites were improved by adding suitable percentage of the filler. Moreover density increased with the increase in percentage of SGM particles in the composites. Thus, the mechanical and wear properties of the epoxy can be improved by including solid glass microspheres in suitable percentage.

C-type natriuretic peptide (CNP) is the major natriuretic peptide of the central nervous system and acts via its selective guanylyl cyclase-B (GC-B) receptor to regulate cGMP production in neurons, astrocytes and endothelial cells. CNP is implicated in the regulation of neurogenesis, axonal bifurcation, as well as learning and memory. Several neurological disorders result in toxic concentrations of ammonia (hyperammonaemia), which can adversely affect astrocyte function. However, the relationship between CNP and hyperammonaemia is poorly understood. Here, we examine the molecular and pharmacological control of CNP in rat C6 glioma cells and rat GPNT brain endothelial cells, under conditions of hyperammonaemia. Concentration-dependent inhibition of C6 glioma cell proliferation by hyperammonaemia was unaffected by CNP co-treatment. Furthermore, hyperammonaemia pre-treatment (for 1 h and 24 h) caused a significant inhibition in subsequent CNP-stimulated cGMP accumulation in both C6 and GPNT cells, whereas nitric-oxide-dependent cGMP accumulation was not affected. CNP-stimulated cGMP efflux from C6 glioma cells was significantly reduced under conditions of hyperammonaemia, potentially via a mechanism involving changed in phosphodiesterase expression. Hyperammonaemia-stimulated ROS production was unaffected by CNP but enhanced by a nitric oxide donor in C6 cells. Extracellular vesicle production from C6 cells was enhanced by hyperammonaemia, and these vesicles caused impaired CNP-stimulated cGMP signalling in GPNT cells. Collectively, these data demonstrate functional interaction between CNP signalling and hyperammonaemia in C6 glioma and GPNT cells, but the exact mechanisms remain to be established.

Preparing the hybrid composite material using LY556 epoxy resin and HY951 hardener was used as the matrix and agave nano fibers with zinc powder use as reinforcement, mixing with help of stirrer at 800 rpm. There are various methods of fabrication technologies are available but here are using hand lay-up method. Study the surface morphology of raw and chemical treated fibers also finding the material used for the hybrid composite is reinforced agave furcrea fibers and zinc powder at different percentages.

Cerebral ischemia is known to be a major cause of death and the later development of Alzheimer's disease and vascular dementia. However, ischemia induced cellular damage that initiates these diseases remain poorly understood. This is primarily due to lack of clinically relevant models that are highly reproducible. Here, we have optimised a murine model of global cerebral ischaemia with multiple markers to determine brain pathology, neurochemistry and correlated memory deficits in these animals. Cerebral ischaemia in mice was induced by bilateral common carotid artery occlusion. Following reperfusion, the mice were either fixed with 4% paraformaldehyde or decapitated under anaesthesia. Brains were processed for Western blotting or immunohistochemistry for glial (GLT1) and vesicular (VGLUT1, VGLUT2) glutamate transporters and paired helical filament (PHF1) tau. The PHF1 tau is the main component of neurofibrillary tangle, which is the pathological hallmark of Alzheimer's disease and vascular dementia. The novel object recognition behavioural assay was used to investigate the functional cognitive consequences in these mice. The results show consistent and selective neuronal and glial cell changes in the hippocampus and the cortex together with significant reductions in GLT1 (***P 0.001), VGLUT1 (**P 0.01) and VGLUT2 (***P 0.001) expressions in the hippocampus in occluded mice as compared to sham-operated animals. These changes are associated with increased PHF1 (***P 0.0001) protein and a significant impairment of performance (*p 0.0006, N = 6/group) in the novel object recognition test. This model represents a useful tool for investigating cellular, biochemical and molecular mechanisms of global cerebral ischaemia and may be an ideal preclinical model for vascular dementia.

This paper presents the erosive wear of MWCNTs/MnO2 nanocomposite. The nanocomposites with 5, 10 and 15 wt% of MWCNTs were fabricated using cost effective powder metallurgy technique. The mass density analysis shows that the green and sintered mass density of the nanocomposites increases with addition of MWCNTs from 5wt% to 10wt% and then decreases from 10wt% to 15wt%. The decrease in density from 10wt% to 15wt% may be due to agglomeration of MWCNTs in the nanocomposites. The erosive wear test was done by self designed erosive wear tester. The erosive wear test indicates that 10 wt% MWCNTs/MnO2 nanocomposite exhibits higher erosive wear resistance as compared to 5 and 15 wt% MWCNTs/MnO2 nanocomposite. The field emission scanning electrone microscope (FESEM) surface morphology of fractured surface shows that the nanocomposites were brittle fractured during erosion process. The erosive wear of the nanocomposite depends highly on its mass density, hardness and dispersion of multiwalled carbon nanotube in H2SO4(aq) solution.

Energy is an important role in any country’s economy and infrastructure growth. Wind energy is renewable form of energy and environment friendly compared to conventional energy resources that pollute the environment. A proper analysis of wind speed data is an important parameter to estimate wind energy potential at a particular site. This article investigates the wind energy potential at three different cities of Assam viz. Dibrugarh, Guwahati and Tezpur of Assam, India by using statistical methods over a period of eight years from 2010-2017. The speed data revealed that the mean wind speed of Tezpur city was lower in-comparison to Dibrugarh and Guwahati. The average wind speed of Dibrugarh is highest i.e. 5.398 km/hr followed by Guwahati city 4.628 km/hr. The average monthly wind data shows that the mean wind speed for city Dibrugarh is highest in the month of April as 7.8625 km/hr. The mean test analysis between Dibrugarh and Guwahati shows that the mean speed different between two cities is significant as P0.05. Weibull probability distribution function revealed that higher occurrence of probability at higher wind velocities for each city. The probability distribution plot shows that the 99% probability of occurance of Wind speed is 7.45093 km/hr for city Dibrugarh. The data also revealed that the average wind power density for the city Dibrugarh is 0.897451 W/m2 followed by city Guwahati 0.578349 W/m2. The above analysis shows that there is a possibility of wind power generation in the city of Dibrugarh followed by city Guwahati at these low wind speed region and the vertical axis wind turbines can be installed for power generation in cities Dibrugarh and Guwahati.

The objective of this study is to illustrate the optimum parameters adopted to evaluate maximum yield of MWCNT/MnO2 nanocomposite. In this paper, the effect of stirring time, Concentration of H2SO4 (aq) solution, solution temperature and drying time on yield of MWCNT/MnO2 nanocomposite was investigated. The orthogonal array, signal-to-noise ratio, and percentage contribution of all parameters are employed to study the yield of MWCNT/MnO2 nanocomposite. After conducting the experiments the yield was measured and Signal to noise ratio was calculated. With the help of graphs, optimum parameter values were obtained at parameter level A2B2C2D1. The percentage contributions of parameters and regression analysis confirmed the concentration of H2SO4 has significant effect on yield of MWCNT/MnO2 powder.

In recent years, attention has been made by researchers to fabricate carbon nano-tubes/Polyaniline (CNTs/PANI) nanocomposites due to its simple method of preparation, low cost, environmental friendly, excellent capacitive performance. The discovery of carbon nanotubes with unique electrical, thermal and mechanical properties has attracted researchers used as a filler material for applications in engineering discipline. This review gives a broad study on ongoing research effort on synthesis, characterization, mechanical and electrical properties of CNTs/PANI nanocomposites.

Recent research has shown that carbon nanotube (CNT) acts as a model reinforcement material for fabricating nanocomposites. The addition of CNT as a reinforcing material into the matrix improves the mechanical, thermal, tribological, and electrical properties. In this research paper multiwalled carbon nanotube (MWCNT), with different weight percentage (5%, 10%, and 15%), was reinforced into manganese dioxide (MnO2) matrix using solution method. The different weight % of MWCNT/MnO2 nanocomposite powders was compacted and then sintered. The phase analysis, morphology, and chemical composition of the nanocomposites were examined by X-ray diffractometer, Field Emission Scanning Electron Microscope (FESEM), and Energy Dispersive X-Ray (EDX), respectively. The XRD analysis indicates the formation of MWCNT/MnO2 nanocomposites. The FESEM surface morphology analysis shows that MnO2 nanotube is densely grown on the surface of MWCNT. Further, microhardness of MWCNT/MnO2 nanocomposite was measured and it was found that 10 wt% has higher microhardness in comparison to 5 and 15 wt%. The microhardness of the composites is influenced by mass density, nanotube weight fraction, arrangement of tubes, and dispersion of MWCNT in H2SO4(aq) solution.

Wind energy is one of the most cost effective renewable energy resources. The purpose of this study is to investigate wind energy potential at different sites in India from year 2008-2017 for six month basis (March to August). The average wind speed data for different sites indicates that the average wind speed for site Tiruchirappalli is highest. The normal probability plot shows that wind speed data are normally distributed except for the site Kolkata. Weibull cumulative probability plot shows that the higher probability of occurrence of wind energy was at higher average wind speed for each site. Weibull probability density function shows that the probability density function is minimum at higher average wind speed. It is also found that the scale parameter is an important parameter compare to shape parameter that affect wind speed. The analysis of power density shows that the average power density for site Tiruchirappalli is highest and lowest for site Agartala. The analysis also shows that higher wind energy possibility is in Tiruchirappalli followed by Coimbatore.

Objective To demonstrate a correlation between anatomic regional changes in Spinocerebellar Ataxia type 6 (SCA6) patients and measures of cognitive performance on neuropsychological tests. Methods Neurocognitive testing was conducted on 24 SCA6 and 28 control subjects. For each cognitive test, SCA6 patients were compared against the controls using Student's t-test. For the cerebellar patients, using voxel based morphometry, correlations between cerebellar gray matter volume at each voxel and performance on the neuropsychological exams were calculated using the Pearson correlation coefficient implemented in SPM8. Results Compared to controls, SCA6 patients exhibited significantly impaired performance on the following cognitive tests: Rey-Auditory Verbal Learning Test Trial V, Controlled Oral Word Association phonemic test and semantic-verb test, Rey-Osterrieth Complex Figure copy test as well as immediate and delayed visuo-spatial memory recall test, Trail Making Test (TMT) Part A and Part B, Stroop Color Task completion time, Stroop Color-Word Task score, and Grooved Pegboard Test (GPT) Dominant and Non-Dominant Hand time. Correlations of gray matter density with cognitive test performance were determined for all SCA6 subjects. Using a p-value threshold of 0.001 and family-wise small volume error correction, significant correlations were found for GPT Non-Dominant, GPT Dominant, TMT Part A, and TMT Part B. Conclusion Different regional patterns of cerebellar involvement were found for the motoric GPT task and the executive version of the TMT. The results for the GPT strongly indicated that the integrity of medial superior hemispheric regions was associated with motor task performance, whereas executive cognitive function was localized in distinctly different inferior regions. This is the first VBM study to differentiate cognitive and motor contributions of the cerebellum.

Background and purpose The Montreal Cognitive Assessment (MoCA) is an increasingly popular clinical screening tool for detecting cognitive impairment in stroke, but few studies have directly compared performance on the MoCA with neuropsychological assessment. Our retrospective study examined the extent to which intact performance on the MoCA reflects intact cognition as determined by neuropsychological assessment. Methods In this retrospective study, cognitive profiles for 136 acute stroke patients admitted to the Acute Stroke Unit who had available MoCA and neuropsychological assessment data were examined. Results 22% of our patients were deemed cognitively intact on the MoCA. Of these, 78% were found to be impaired (≤ 5%ile) on neuropsychological assessment in one or more cognitive domains. The most common impairments were in general intelligence, information processing speed and visual memory; three areas not assessed by the MoCA. In addition, a high proportion (up to 59%) of patients who scored the maximum points in one of the MoCA-specified domains were impaired on comparable neuropsychological assessment. Conclusions Our findings suggest that although the MoCA may be a useful screening tool post-stroke in detecting gross impairments, neuropsychological assessment is still necessary for a comprehensive and reliable detection of domain-specific cognitive deficits, which can more reliably inform us for realistic goal setting and vocational advice vital for effective rehabilitation.

This paper presents the analysis of erosive wear rate of Al2O3-Cu composite with 0, 1, 3, 5 and 7 wt% loading of Al2O3 particles. Composite samples were fabricated through cost effective powder processing technique. The surface morphology of the composites was analysed by Scanning Electron Microscope (SEM) and composition was examined by Energy Dispersive X-Ray (EDX). The density analysis show that the mass density increases with increase in wt% of Al2O3 particles up to 5 wt% and then decreases from 5 wt% to 7 wt% o. The decrease in mass density of composite at 7 wt% of Al2O3 particles may be due to agglomeration of Al2O3 particles. Hardness results show that the addition of Al2O3 particles, the hardness value increases up to an optimum level of wt% of Al2O3. The analysis of erosive wear shows that the erosive wear rate decreases with increasing wt% of Al2O3 from 0 wt% to 5 wt% of Al2O3 particles and then increases to 7 wt%. The erosive wear rate of the Al2O3-Cu composite depend on optimum level addition of Al2O3, sintered mass density, hardness value and distribution of Al2O3 particle in the composite.