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Data Preprocessing for Modelling the audulteration detection in Gasoline with BIS
No full textIn India major fuel pollution is caused in the Transport sector as the major hydro carbons are utilized by the transport vehicles.
This is the main concern that warrants better utilization of fuels for the environmental friendly and also the Honourable Judiciary. The foremost proposal for containing the air pollution is the appointment Committee by Indian government. It is very difficult to detect the adultered fuel with visual examination as the basic fuel is added with other cheaper boiling point range hydrocarbons having more or less similar composition leading to alter and degrade the quality of the base fuel. The committee proposals with respect to the Auto Fuel Policy and to devise a road map for its implementation along with the alternate fuels for transport, specifications for the fuel quality along with others are the main concern for reduction of environmental pollution
Development of Granite Powder Reinforced Epoxy Composites
No full textThis study was conducted to evaluate the development and characterization of granite powder reinforced epoxy composites.
Granite powder in powder form acts as reinforcement in Epoxy matrix. The primary aim of this study was to investigate the
effectiveness of these composite materials in the strength, weight and surface finish. It has the capability of replacing the present materials due to its eco-friendly nature. The compositions with poor properties are considered noncompliant and can be rejected. In this study, the samples are subjected to various Physical and Mechanical tests like Izod impact test, Vickers hardness test and Moisture absorption. This work aims to account these results in order to obtain enhanced properties. It is found that resin ratio between 60% to 70% are the best suitable for the engineering and structural applications as well
Synthesis and characterization of thermally stable and flame retardant hexakis(4- aminophenoxy)cyclotriphosphazene-based polyimide matrices
No full textABSTRACT
A new approach to the preparation of hexakis(4- aminophenoxy)cyclotripho�sphazene (HACTP) based polyimide (PI) matrices is proposed, for improved thermal and flame retardant properties. HACTP was synthesized with good yield. The structure of HACTP was confirmed by various characterization techniques, such as FTIR, NMR, and mass Spectroscopy. Polyimide matrices were prepared by thermal imidization process using HACTP and dianhydrides using N-methyl pyrrolidone as a solvent. The successful formation of HACTP-based polyimide matrices was confirmed by the FTIR. Thermal properties of the PI were analyzed using DSC and TGA techniques. Data obtained from the thermal studies indicate that the HACTP-based PI possesses better thermal and flame retardant properties
Hematite Photoanode with Complex Nanoarchitecture Providing Tunable Gradient Doping and Low Onset Potential for Photoelectrochemical Water Splitting
No full textAbstract
Over the past years, α-Fe2O3 (hematite) has re-emerged as a promising photoanode material in photoelectrochemical (PEC) water splitting. In spite of considerable success in obtaining
relatively high solar conversion efficiency, the main drawbacks hindering practical application at hematite are related to an intrinsically hampered charge transport and a sluggish kinetics of the oxygen evolution reaction on the photoelectrode surface.
In the present work, we report a strategy how to synergistically address both these critical limitations. Our approach is based on three key features that are applied simultaneously,
specifically i) a careful nanostrcuturing of hematite photoanode in the form of nanorods, ii) doping of hematite by Sn4+ ions by a controlled gradient, and iii) surface decoration of hematite by a new class of double hydroxide layered (LDH) OER co-catalysts based on Zn-Co LDH. All three interconnected forms of functionalization result in an extraordinary cathodic shift of the
photocurrent onset potential by more than 300 mV and a PEC performance that reaches a photocurrent density of 2.00 mA/cm2 at 1.50 VRH
Numerical and experimental nonlinear dynamic response reduction of smart composite curved structure using collocation and non-collocation configuration
Get PDFIn this work, a generic geometrical nonlinear mathematical model of smart composite curved shell panels has been
developed for the evaluation of the linear and nonlinear dynamic responses. Further, the dynamic deflections are reduced by employing the piezoelectric material with the parent composite using two different arrangements (sensor and actuator). The current layered structure model is developed based on the higher-order mid-plane kinematics including the
stretching effect. The electric potential due to the piezoelectric material included via a quadratic function of thickness for
the current combined electro-elastic modeling. The geometrical distortion of the smart shell panel structure accounted
via Green-Lagrange strain field including all of the nonlinear higher-order terms. The desired responses are evaluated
computationally using an original computer code (MATLAB environment) with the help of the current higher-order
model and finite element steps. The nonlinear dynamic deflection values are obtained through the direct iterative method in conjunction with Newmark’s integration. Additionally, the accuracy of the proposed model is demonstrated via comparison study with the available published literature with and without electric field potential. The reduction of response frequencies is also compared with the in-house experimental data. Lastly, few more numerical examples are computed for the various geometrical parameter including the shell configuration and the comprehensive behaviour of the currently developed nonlinear numerical model for the analysis of smart layered structure discussed in details
Effect of process parameters on surface roughness and amplitude of vibration in micro milling of AISI 304 steel, International
No full textMicromilling is one of the important machining processes used to make complex shapes with required surface quality. The micro milling is carried out with mill cutters which are having diameter less than 1mm at high spindle rotational speeds. Aim of the present study to investigate effect of process parameter such as spindle rotational speed, feed and depth of cut on amplitude of cutter vibration and surface roughness
for micromilling of AISI 304 steel. As per full factorial design of experiments, 27 experiments were conducted on ASIS 304 at dif erent levels of process parameters. A Laser Doppler Vibrometer was used for on-line measurement of cutter vibration in the
form of acousto optic emission signals. The signals were processed using Fast Fourier transformer to read the amplitude directly. In addition to that, surface roughness was
also measured for all the experiments. The experimental results were analysed using analysis of variance technique to identify significant parameters. Interaction effect of process parameters on the amplitude of cutter vibration and the surface roughness
was also studie
Structural, Electrical and Dielectric Properties of Nickel Doped Spinel LiMn2O4 Nanorods
No full textSpinel pure and Ni-doped LiMn2O4 nanorods were synthesized by a rapid microwave-assisted hydrothermal process followed by a solid-state reaction method. Their structural, morphological, electrical, and dielectric properties were investigated by X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, Raman spectroscopy, transmission electron microscopy (TEM), and impedance spectroscopy techniques. Powder XRD studies revealed that all the synthesized samples have well-defined cubic crystal structure and the Ni2+ doping in manganese sites did not affect spinel LiMn2O4 structure. TEM images of pure and Ni-doped LiMn2O4 samples clearly showed the formation of well-dispersed nanorods with uniform distribution. The Ni2+ doping did not affect the nanorod morphology of pure LiMn2O4. The spinel LiMn2O4 nanorods showed an electrical conductivity of 3.13 × 10−4 S cm−1, at room temperature. The A.C conductivity studies revealed that the pure and Ni-doped LiMn2O4 nanorods obey Jonscher’s power law. The dielectric studies revealed that the dielectric constant of the samples decreases with frequency, which is due to decrease in charge accumulation at the interface
A Comparative Experimental Study on Fault Diagnosis of Rolling Element Bearing using Acoustic Emission and Soft Computing Techniques
No full textIn engineering processes, Health condition Monitoring (HCM) is a fault�finding task to guarantee consistency of rotating machinery. Rolling Element Bearings (REBs) are the main origin of damage in such equipment. They are the key components used in most of the rotating devices. These faults are mainly caused due to premature failure or improper installation of the machine element. Finding and analysis of defects is very vital in rotating machinery for its optimality. A test-rig was established to analyze the various line defects in REBs under different
speeds and load conditions. The Acoustic Emission (AE) signatures responses are obtained and analyzed. Soft computing methods, especially Artificial Neural Network (ANN) and Support Vector Machine (SVM) used to compare with experimental results for fault diagnosis of bearings. The
AE statistical features were fed as inputs in ANN and SVM. A comparative experimental study on prediction of seeded defect size is carried out using soft computing methods. This study concludes that these methods can be used for prediction of rolling element bearings seeded fault
Photoactive Brownmillerite Multiferroic KBiFe2O5 and Its Potential Application in Sunlight-Driven Photocatalysis
No full textKBiFe2O5 (KBFO) is an upcoming promising brownmilleritestructured multiferroic photoactive material for next-generation photovoltaic and photocatalytic applications. In the present work, KBFO has been developed using multistep thermal treatment method to reduce the volatility of constituent
elements and improve the stability of compound. The band gap of KBFO (found to be ∼1.68 eV) extends to the near-infrared region compared to traditional perovskite-structured multiferroics. The magnetic and dielectric transitions occur
in the same temperature range (740 K−800 K), reflecting the existence of magneto-dielectric effect in the as-synthesized sample. It also shows promising photocatalytic activity by degrading organic effluents under natural sunlight
compared to regular perovskite BiFeO3 photocatalyst (operating under visible light). A new application of brownmillerite multiferroic KBFO photocatalyst in environmental and energy applications has been explored by integrating the structural, optical, magnetic, and dielectric properties of the same
Role of biosurfactants in bioremediation of oil pollution-a review
Get PDFThe energy resources mainly petroleum and petroleum hydrocarbons are major pollutants of the environment. The oil and oil products contamination may cause severe harm and hence, the attention has been remunerated in the development of alternative technologies for elimination of these contaminants. Biosurfactants were used in the remediation of oil pollution due to advantages such as biodegradability and low toxicity. The biosurfactants are produced from low
cost substrates like agro-industrial wastes which reduce the cost of production. Biosurfactants and bioemulsifiers are amphiphilic compounds and are produced as extracellular or a part of the cell membrane by bacteria. The insight view, how hydrocarbons are degraded by microorganisms and thereby reduce the damage of ecosystem is highly essential to target the
problem. Biofilms are the bacterial communities which protects the bacterial cells from various adverse conditions. The present review describes the biosurfactants and its synthesis from
bacteria and also emphases on the role of surfactants in oil remediation