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The nanocrystalline Bi2O3 powder was synthesized by ultrasonicated microwave irradiation by employing centrifugation technique at all normal conditions. Fabrication of thick films of pure Bi2O3 powder was made by screen printing and firing at 400oC for 30 min. Surface activations of the films involved the dipping of pure films into 0.01M aqueous solution of Gallium Nitrate for different intervals of time. The morphologies, surface topographies, constituents of elements present in the synthesized materials and crystallographic structures of the pure and surface activated films have been investigated by XRD, FE-SEM, E-DAX, etc. It has been investigated that, the Ga2O3 activated Bi2O3 (30 min) sample exhibits crucial response to 20 ppm Cl2 gas at 250oC. Electrical and gas monitoring performance of thick films of pure and activated Bi2O3 have been studied and discussed.

The electric vehicle is the new domain of researcher because the replacement of Internal combustion engine. According to working principle, there are quite challenging aspects of electric vehicle. The high speed, low friction and controlled NVH are demanding factors from parts’ manufacturers. In this paper, the acoustic failure of a ball bearing is studied for an application of high-speed induction motor. The root cause of bearing is identified from the batch of similar bearings. To validate the failure behavior, life durability testing of bearing is carried out. The testing incorporates the acoustic measurements, temperature monitoring and capturing the revolutions of bearing. Results are presented in the form of acoustic sound pressure plots with noise level as well as corresponding temperature. The study reveals that even the deep groove ball bearing is made from good quality of material, but grinding and super-finishing can be responsible for the unintentional cause of the defect. The author has recommended the threshold values of waviness as well as the intensity of stone marks to manufacture the premium class bearings for electric vehicles.

Graphene quantum dots (GQDs), impressive materials with enormous future potential, are reviewed from their inception, including different precursors. Considering the increasing burden of industrial and ecological bio-waste, there is an urgency to develop techniques which will convert biowaste into active moieties of interest. Amongst the various materials explored, we selectively highlight the use of potential carbon containing bioprecursors (e.g. plant-based, amino acids, carbohydrates), and industrial waste and its conversion into GQDs with negligible use of chemicals. This review focuses on the effects of different processing parameters that affect the properties of GQDs, including the surface functionalization, paradigmatic characterization, toxicity and biocompatibility issues of bioprecursor derived GQDs. This review also examines current challenges and s the ongoing exploration of potential bioprecursors for ecofriendly GQD synthesis for future applications. This review sheds further light on the electronic and optical properties of GQDs along with the effects of doping on the same. This review may aid in future design approaches and applications of GQDs in the biomedical and materials design fields.

A novel imidazolium-based highly efficient, recoverable, and reusable basic ionic liquid [PEMIM][OH] was synthesized using a very simple approach. This ionic liquid was employed as a catalyst for the multicomponent synthesis of tetrahydrobenzo[b]pyran derivatives by the condensation of dimedone, malononitrile and various substituted aldehydes as key starting materials in aqueous media. Novelty, the efficacy of the catalyst, high yields of desired products, greener approach, high atom economy and use of aqueous media make this protocol worthwhile. The inventive idea of employing halide and a metal-free ionic liquid catalyst establishes this as a sustainable process. The cost-effective isolation of pure, high yielded desired product by sidestepping the column and recrystallization technique was also demonstrated in this protocol. A plausible mechanism for the formation of tetrahydrobenzo [b] pyran is proposed. The novel catalyst and synthesized compounds were characterized by using various analytical techniques such as FTIR, 1H NMR, 13C NMR, DEPT-135, LC-Mass, Elemental, HSQC, HPLC, TG-DSC, TG-DTG and single crystal XRD analysis.

Researchers all over the world have provided significant and effective solutions to detect malicious URLs. Still due to the ever changing nature of cyberattacks, there are many open issues. In this paper, we have provided an effective hybrid methodology with new features to deal with this problem. To evaluate our approach, we have used state-of-the-arts supervised decision tree learning classifications models. We have performed our experiments on the balanced dataset. The experimental results show that, by inclusion of new features all the decision tree learning classifiers work well on our labeled dataset, achieving 98-99% detection accuracy with very low False Positive Rate (FPR) and False Negative Rate (FNR). Also we have achieved 99.29% detection accuracy with very low FPR and FNR using majority voting technique, which is better than the wellknown anti-virus and anti-malware solutions.

Gout is the world's most popular inflammatory arthritis and the prevalence of gout is rapidly rising worldwide. Typically, gout develops in a single joint as excessive swelling and intense pain wherein excessive deposition of uric acid (UA) crystals results in inflammation of the joint. Accordingly, UA is considered an effective biomarker to diagnose gout. Recently, the use of innovative sensors has attracted great attention, as it is effortless, responsive, quick, and powerful. While the traditional sensors for UA assessment are widely used, they pose many limitations and hurdles in terms of sensitivity, selectivity, and simplicity. In this vein, metal ions and organic ligand-based metal–organic framework (MOF) have gained much attention for the recognition of UA due to its larger surface area, porosity, high sensitivity, and defined selectivity. In this review, we provide details on the latest developments of MOF-centered biosensors for sensitive detection of UA. The status of gout, fundamentals of MOF, and MOF availed for detection of UA have been elaborated. Besides, we highlighted the nanoparticles and conjugates that rely on advanced strategies along with MOF that boost the sensitivity and selectivity towards the UA. Interestingly, different surface architectured MOFs biosensors showed a lower detection limit for UA from μM to nM. Finally, the threats and potential opportunities for MOF-based UA biosensors have been summarized. Therefore, based on ongoing research, the commercialization of this advanced platform for the biosensing of diverse biomarkers will open a new door for the in vitro diagnosis of assorted diseases.

Objective: To detect malicious JavaScript code in Web pages by reducing false positive and false negative rate thus increasing detection rate. Methods/Analysis: In recent years JavaScript has become the most common and successful attack construction language. Various approaches have been proposed to overcome the JavaScript security issues. In this paper, we have presented the methodology of detection of malicious JavaScript code in the Web pages. We have collected the benign and malicious JavaScript's from the benchmark sources of Web pages. We have used the static analysis of JavaScript code for the effective detection of malicious and benign scripts. We have created a dataset of 6725 benign and malicious scripts. This dataset consists of 4500 benign and 2225 malicious Java Script's. Finding: We have extracted 77 JavaScript features from the script, among which 45 are new features. We have evaluated our dataset using seven supervised machine learning classifiers. The experimental results show that, by inclusion of new features, all the classifiers have achieved good detection rate between 97%-99%, with very low FPR and FNR, as compared to nine well-known antivirus software's. Novelty/Improvement: We have used 45 new JavaScript features in our dataset. Due to these new features, FPR and FNR are reduced and increase the malicious JavaScript detection rate.

Present investigation reports the extracellular synthesis of silver nanoparticles by green, low cost and simple method using naturally grown mushroom species (Agaricus species). The colour of the reaction medium was changed from colourless to brown within 10 h indicated the formation of silver nanoparticles. The prepared silver nanoparticles were characterized using UV-visible spectroscopy, FTIR spectroscopy, particle size analyzer and zeta potential. The SPR peak in UV-spectrophotometer was recorded at 419 nm which confirms the formation of silver nanoparticles. The bands appeared in FTIR spectra showed the presence of possible biomolecules responsible for the reduction of silver ions. Particle size analyzer measured the average size in the range between 20 nm and 50 nm. The negative value of the zeta potential recommends the stability of the prepared silver nanoparticles. The formed silver nanoparticles were evaluated for their catalytic activity for the reduction of methylene blue by NaBH4 and exhibit the reduction in 5 min. Therefore, the prepared silver nanoparticles played significant role in the maintenance of environment.

In the present study, TiO2 nanorod array (TiO2 NRA) structure was synthesized on FTO substrate using the hydrothermal method. The effect of hydrothermal temperature and growth time on the morphology of TiO2 NRA was studied in this work. Structural and morphological properties of synthesized TiO2 NRA were investigated using X-ray diffraction (XRD) and Field emission scanning electron microscope (FE-SEM). The optical properties were evaluated using UV–Vis spectroscopy, and fluorescence spectroscopy. From XRD, it was confirmed that synthesized TiO2 have rutile phase. FE-SEM study reveals that synthesized TiO2 nanorods have square shape and tetragonal structure having a size of 50 nm and length of 1 μm. The TiO2 nano-rod array has surface defects such as oxygen vacancies were confirmed by photoluminescence study.

In this paper, topology of Grid connected single step (GCSS) high gain buck-boost inverter with fuzzy maximum power point tracking (MPPT) controller is discussed. It can step up/down the output from PV & performs DC to AC conversion simultaneously in a single step with the help of fuzzy MPPT controller. This scheme has features such as high gain, less switching loss & with the help of fuzzy MPPT it tracks maximum power from PV very efficiently. Thus this scheme is conformable for PV applications with low voltage & varrying with time conditions. Design of proposed GCSS elements with derived equations & design of fuzzy MPPT is given in this paper. Presented topology is designed using MATLAB/SIMULINK. Detailed simulation of presented GCSS with fuzzy MPPT and it's results are given.

Surface plasmon resonance (SPR) offers exceptional advantages such as label-free, in-situ and real-time measurement ability that facilitates the study of molecular or chemical binding events. Besides, SPR lacks in the detection of various binding events, particularly involving low molecular weight molecules. This drawback ultimately resulted in the development of several sensitivity enhancement methodologies and their application in the various area. Among graphene materials, graphene-based nanocomposites stands out owing to its significant properties such as strong adsorption of molecules, signal amplification by optical, high carrier mobility, electronic bridging, ease of fabrication and therefore, have established as an important sensitivity enhancement substrate for SPR. Also, graphene-based nanocomposites could amplify the signal generated by plasmon material and increase the sensitivity of molecular detection up to femto to atto molar level. This review focuses on the current important developments made in the potential research avenue of SPR and fiber optics based SPR for chemical and biological sensing. Latest trends and challenges in engineering and applications of graphene-based nanocomposites enhanced sensors for detecting minute and low concentration biological and chemical analytes are reviewed comprehensively. This review may aid in futuristic designing approaches and application of grapheneous sensor platforms for sensitive plasmonic nano-sensors.

A proficient and meticulously designed diasterioselective, multicomponent, one-pot synthesis of densely substituted piperidine derivatives has been elaborated using polystyrene sulfonic acid catalyst via tandem reactions of 1,3-dicarbonyl compounds, aromatic aldehydes and various amines. Shorter reaction times, high yields and a polymer-supported inexpensive catalyst are the noteworthy aspects of the scaffold.

The new facile approach has been developed for the synthesis of spiro [diindenopyridine-indoline] triones under the umbrella of green chemistry. The developed protocol is endowed with the use of low transition temperature mixture as a green reaction medium, operational simplicity, easy workup procedures, good to excellent product yields, and non-chromatographic purification procedure. Since indenone fused motifs have a broad spectrum of biological activities, this protocol is expected to find application in the combinatorial synthesis of biologically active compounds.

Titanium substituted Zn–Mn ferrites were prepared by sol–gel route. Formation of single phase cubic spinel structure for all the compositions was confirmed from their X-ray diffraction studies. These ferrite samples existed as uniform and homogenous grain size as observed from scanning electron microscopy technique (SEM). The magnetic studies indicated that, the ferrimagnetic behavior increases with titanium substitution. Dielectric constant and complex impedance were measured as a function of frequency in the range 20 Hz–1 MHz. Frequency dependence of dielectric constant shows dielectric dispersion due to the Maxwell–Wagner type of interfacial polarization and impedance study reveals that the electrical conduction in the ferrites is by the interior of the grain boundaries. In general, the substitution of titanium plays an important role in changing the structural, magnetic and electrical properties of these ferrites.

A highly competent-diversity oriented synthesis of coumarin core derivatives using a Knoevenagel condensation followed by Michael addition and subsequent cyclization in the presence of (±)-camphor-10-sulfonic acid in a water/ethanol (1:1) solvent system is depicted. Furthermore, easy workup procedures with good yield, rapid reactions with high atom economy, and catalyst recyclability are the fascinating features of the procedure.

Neural network controllers are network systems which have been inspired from biological neurons. Artificial neural networks (also known as ANN) work on the principle of learning where the networks learn based on the data provided to the network. The paper constitutes of implementation of ANN on temperature-controlled process like Single board heater system (also known as SBHS). Feedforward backpropagation algorithm has been used for system learning. ANN controller learning is done using Levenberg Margaret Algorithm which is the fastest algorithm for supervised learning[12]. ANN controller used has three layers namely input layer, hidden layer and output layer. The training data set which has been provided to the controller is the open loop response of the system. The responses performance plots, time series plot and regression plots for a variety of input data sets have been plotted.

This paper deals with the design, analysis and simulation of new power factor corrected multiple output switched mode power supply based on bridgeless buck-boost converter. Conventional SMPS with diode bridge rectifier depict power quality related indices for e.g. high distortion in input current, low power factor. In order to resolve this power quality related problem new bridgeless converter based SMPS is proposed. Comparing with conventional topologies this proposed topology reduces conduction losses and helps to improve the power quality. The performance evaluation of multiple output SMPS is done under steady state and varying input voltage. The performance of this SMPS is simulated in MATLAB/Simulink environment.

The Flexible AC Transmission System (FACTS) technology is a auspicious technology to achieve complete deregulation of power system based on power electronic devices. Static VAR Compensator (SVC) is one of the shunt connected devices, which can be utilized for the purpose of voltage and reactive power control in power systems.This paper deals with the analysis, design and of TCR based reactive power compensation and voltage regulation.Topology for closed loop reactive power compensation suitable for dynamic loads using TCR is presented. Firing angle range of TCR is selected in such a way that to keep the harmonic content at minimum level. Another approach to achieve the complete closed loop control of TCR is by using system identification. By proper linearization of TCR characteristics we can find different transfer function for linear ranges using system identification toolbox in MATLAB. The dynamic equations for TCR SVC model will be presented in the form of transfer function.

System identification is an important task of modelling of a process. A model merely represents the actual process in much simpler format. Modelling is required to obtain the actual insights of the process. Modelling can be done using system identification techniques. This work various system identification techniques to obtain plant transfer function. The prototype used is a Single Board Heater System which is temperature control process with heater and fan. The system identification of the process is done by using data driven or black box modeling. Open loop system identification is done using three tests namely step, ramp and PRBS (pseudo random binary signal). The temperature control system mentioned is susceptible to ambient temperature variations. So closed loop system identification of the system is done using direct method. Various controllers were designed namely PI, PID, and 2DOF pole placement controller. The analysis of the control algorithms is done using LabVIEW, Scilab and Matlab.

Thick films of bulk tin oxide powder were observed to be less sensitive to polluting, hazardous and inflammable gases. So, nanostructured ZrxSn1-xO4 powder was synthesized by disc type ultrasonicated microwave assisted centrifuge technique. Thick films of nanostructured pure Zr(0.75)Sn(0.25)O4 powder were fabricated by screen printing technique. These films were surface functionalized by SrO2 for different intervals of time followed by firing at 450°C for 30 min. The surface morphology, chemical composition, crystal structure, electrical and gas sensing performance of the unmodified and surface functionalized nanostructured Zr(0.75)Sn(0.25)O4 powder by SrO2 have been investigated by FESEM, E-DAX, XRD, etc.

Polyaniline and it`s nanocomposites with ZnO were successfully synthesized by photo-induced polymerization method with various concentrations of ZnO, followed by characterizations viz. SEM, EDAX, XRD, FTIR and UV-Vis. Thick films of synthesized powders were fabricated by screen printing technique for monitoring various gases at different operating temperatures and at various gas concentrations. CuO activated polyaniline-ZnO nano-composite exhibits maximum response of ethanol gas at room temperature. The sensor exhibits high sensitivity, highest selectivity, quick response, fast recovery, long term stability, etc. An exceptional sensitivity was found to low concentrations of ethanol gas at room temperature and no cross sensitivity was observed even to high concentrations of other hazardous and polluting gases. The efforts have been made to develop the ethanol sensor based on PANI and its nanocomposites. The effects of microstructure and surfactant concentration on the ethanol response, selectivity, response and recovery of the sensor in the presence of ethanol gas were studied and discussed.

A novel series of benzo crown ether (dibenzo 18-crown-6 ether, benzo 18-crown-6 ether, and benzo 15-crown-5 ether) functionalized enamines derivatives from amino benzo crown ether (4-amino dibenzo 18-crown-6 ether, 4-amino benzo 18-crown-6 ether, 4-amino benzo 15-crown-5 ether) and substituted 3-(dimethylamino)-1-phenylprop-2-en-1-one compounds have been synthesized. All the synthesized compounds were characterized by infrared, 1H NMR, 13C NMR, distortionless enhancement polarization transfer, and mass and elemental analysis techniques. The cation recognition property for benzo crown ether enamine 8a was studied by absorption and fluorescence spectroscopy.