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We have investigated the electronic properties of pristine and Cl functionalized zigzag graphene nanoribbons (ZGNR) by employing density functional theory (DFT) based calculations. The migration pathways of Cl adatom adsorption on Cl functionalized ZGNR are also discussed. It is revealed that Cl functionalization results in additional electronic states across the Fermi level which enhances the metallic character of ZGNR. Interestingly, it is predicted that migration of Cl adatom on ZGNR network is most likely to take place along the ribbon edges whereas migration across the ribbon width is found least energetically favorable. [ABSTRACT FROM AUTHOR]

It's a growing issue our clothes get burnt when ironing. This occurs primarily when the iron box is left idle when making some phone calls or other activities. Ironing works by loosening the bond between polymer long-chain molecules in the material fibers. It is a concept that uses an innovative structure and motorized mechanisms to efficiently iron various clothes by reducing the ironing task difficulties. This is a protection tool that is extremely useful in every household. It will be an affordable, foldable machine that can iron any cloth within a time frame. It uses an ultrasonic sensor, which detects the iron box's distance from the fabric. The distance from the cloth is constant, as the iron box is left idle. Using this philosophy, for a given time, a sensor senses the distance. Further LED blinks and buzzer sets on as the gap continues to be constant. The power gets cut off after this as the iron box is still idle. And we can avoid the burning off of our clothes. [ABSTRACT FROM AUTHOR]

Chemical vapor deposition has opened the possibility to grow high purity synthetic diamond at relatively low cost. This has opened up uses of diamond based detectors for wide range of applications. These detectors are most suitable for harsh environments where standard semiconductor detectors cannot work. In this paper, we present the fabrication details and performance study of polycrystalline diamond based radiation detector. Effect of different operating parameters such as bias voltage and shaping time for charge collection on the performance of detector has been studied. [ABSTRACT FROM AUTHOR]

Ba1-xCax Zr0.52Ti0.48 O3 ceramics was prepared by sol gel method. The crystallite size was in nano scale range. The dielectric constant was increased with increase in Ca2+ concentration in the sample. The dielectric loss was decreased with increase in ca concentration in the sample. The ac conductivity of the sample was increased with increase in Ca2+ concentration in the sample. The ac conductivity of the sample follows Johnscher power law. AC conductivity analysis shows that the interactions between neighbouring dipoles were decreased with the increase in Ca2+ concentration in the sample. [ABSTRACT FROM AUTHOR]

Single-Phase BaTiO3 (BTO) and Cr3+ ions doped BTO i.e. BaTi0.8Cr0.2O3 (BTCO) were prepared by solid state reaction of ceramics. The value of dielectric permittivity at room temperature (ε'RT ~1200 at 100 Hz) of BTO was found to be higher than BTCO (ε'RT ~1000), this type of behavior may be ascribed due to distortion in lattice parameters (c/a). Substitution of Cr3+ ions at the site of Ti4+ ions (d0) will create oxygen vacancies and induce O2-(p)-Cr3+(d) hybridization. Magnetic moment of BTCO was found to be ~ 0.02 emu/g at an applied magnetic field of 4 kOe. The value of the magnetocapacitance was observed ~3.3%, which may be a sign of magnetoelectric coupling in the Cr3+ ions doped BTO multiferroic system. [ABSTRACT FROM AUTHOR]

From the past several year's educational institutions at every level was practicing conventional teaching-learning process. It seems to be the only way of imparting education to the learners. However, due to the onset of Coronavirus, i.e., Covid19, everything came to a halt for a while all over the world. The complete ecosystem of human society gets affected by this. Educational institutions also hit hard by this pandemic, and the complete layout of the teaching-learning process over the globe changed. It brings challenges for both students and teachers to withstand in this tough situation and to restore the backbone of learning. E-learning activities slowly-slowly gripped the complete educational ecosystem and the way of imparting education also changed. The primary purpose of this study is to examine the level of cognition faced by e-learners as compared to traditional learners at higher education level during Covid19. For this study, 120 students from Chitkara University have voluntarily participated and submitted their responses through the Google Form. It deduces from this study that learners using E-learning mode feel more cognitive load as compared to traditional learners. The cohen's d-value which represents the effect size comes to be 0.97 which means that the effect of cognitive load is significantly large on e-learners than the traditional learners. In the future, the reasons behind the rise of the cognition level of e-learners need to evaluate and improve the learning gain of e-learners. [ABSTRACT FROM AUTHOR]

The combustion of homogeneous charge compression ignition (HCCI) fuelled with methanol was achieved on a modified CI engine by heating the intake air. The effects of intake temperature and mixture concentration on HCCI combustion characteristics and emissions were analyzed in this paper. Initially the experimental run with pure diesel then the piston is modified with CE Coated Engine - Aluminium oxide Al2O3 and addition of methanol on HCCI engine, then the same type of experimental have been carried under the Lemon Grass Methyl Ester (LGME) with coating and methanol in HCCI Engine. The result of the experiment with performance of BTE increases with coated engine and decreases by addition of methanol, LGME blend results has decreases and increases with (CE) and decreases by addition of methanol. BSFC results increased with all condition because the blend and thermal coating had a higher viscosity and lower energy content. The emission results such as CO, HC NoX and smoke were the NoX is slightly increased when compared to other emission in future the impact of adopting a varied compression ratio and technique to analysis the NoX emission control. [ABSTRACT FROM AUTHOR]

Single phase double perovskite Sr2NiWO6 was synthesized by high temperature solid state reaction method. Crystal structure of the sintered sample was determined using X-Ray Diffraction (XRD) at room temperature. Space group (I4/m) and tetragonal symmetry of Sr2NiWO6 was confirmed by Rietveld refinement through Full-prof suite software, along with a small impurity phase of SrWO4 and Sr2WO5 at 27.70˚ (2θ). Small values of residual factor, weighted residual factor (R factors) and chi2 (χ2) demonstrated a good relation between observed and calculated intensities. For the calculation of bond length and bond angles, Visualization for Electronic Structural Analysis (VESTA) software was used. Micro-structural and elemental composition analysis of the synthesized sample was analysed using Field Emission Scanning Electron Microscope (FESEM) with Energy Dispersive X-Ray (EDX). Also, phonon modes for vibration of octahedra (WO6) were investigated by Raman spectroscopy at room temperature. [ABSTRACT FROM AUTHOR]

The solid state approach was used to synthesizedBaTiO3 based lead-free 0.9Ba0.2Sr0.8TiO3-0.1Bi(Li0.5Nb0.5)O3 perovskite ceramic. Analyzing the stability and deformation of the crystal structure was done using the tolerance factor. The sample's structural features were examined using X-ray Diffraction. The Pseudo-Voigt function was utilized to match the XRD patterns, and the Rietveld refinement was used to confirm the mixed cubic and tetragonal symmetry with space groups Pm-3m and P4/mmm. The Scherrer's formula was used to calculate the sample's peak broadening and identify the size of the crystallites. Energy dispersive X-ray microanalysis and FESEM method were used to determine the elemental composition and surface morphology of the same sample, which had an average grain size of 132nm. The Maxwell-Wagner theory of polarization, which is consistent with Koop's model's phenomenological theory, explains the dispersive behavior of the dielectric constant and dielectric loss. The response of the dielectric of produced sample was examined at temperature variations throughout the frequency range of 1 kHz to 1 MHz. [ABSTRACT FROM AUTHOR]

Twitter is an American social networking and blogging site where users can communicate through messages known as "Tweets. The number of characters is restricted to 280 for all languages except Korean, Chinese and Japanese. Users on social media platforms tend to easily believe the contents of posts related to any random events and some of these events happen to be fake. Twitter spammers may fulfill their malicious objectives, such as spam sending, distributing malware, hosting botnet command and control (C&C) networks, and launching other illicit activities in the underground. Hence, we have proposed a system that will not only help in finding the type of spammers but also eliminate identical tweets. So we have implemented multi-classifier algorithms such as naive Bayes, K-Nearest neighbor, Decision tree and Random forest on a dataset obtained from Twitter and their performance is compared, also the most accurate algorithm is found out. The results of the experiment have been very positive. [ABSTRACT FROM AUTHOR]

We have investigated magnetization properties of the sol-gel prepared SrCo0.95Mn0.05O3 (SCMO) sample with respect to change in structural symmetry. The X-ray diffraction patterns show the crystal structure changes from nH-hexagonal, showing trigonal symmetry (SCMO1), to 2H-hexagonal phase (SCMO2). The trigonal crystal symmetry was obtained at lower annealing temperature (less than 1100 °C), however, the 2H-hexagonal symmetry was obtained at higher annealing temperature. The crystallite size calculated using Debye Scherer formula is found to be ∼ 46 nm and ∼ 33 nm for SCMO1 and SCMO2 samples respectively. The temperature dependence zero field cooled (MZFC) and field cooled (MFC) magnetization curves measured under the applied magnetic field of 500 Oe show magnetic reversibility for the SCMO1 sample. However, MZFC and MFC curves in hexagonal phase show magnetic irreversibility with onset temperature, Tirr ∼ 150 K, exhibits weak ferromagnetic ordering. The temperature variation of magnetization in paramagnetic region was analyzed by following Curie-Weiss law fitting. The χ−1(T) curve shows complete linear behavior with single slope for SCMO1 sample, whereas, the SCMO2 curve exhibit the linear behavior with two distinct slopes. Interestingly the sample in hexagonal phase shows small hysteresis loop at 2 K and 100 K respectively. [ABSTRACT FROM AUTHOR]

We have studied the effect of Cu doping at Mn-site on structural and magnetic properties of a nanocrystalline La0.7Te0.3Mn0.9Cu0.1O3. The nanocrystalline La0.7Te0.3Mn0.9Cu0.1O3 sample was prepared by sol-gel method. X-ray diffraction analysis using Rietveld refinement revealed that the sample crystallized in rhombohedral crystal structure with R 3 ¯ c space group. Debye Scherer’s formula was used to calculate crystallite size and was found to be ~25 nm. Scanning electron microscopy images confirmed the homogeneity of the nanocrystalline sample. The temperature dependence data shows ferromagnetic-paramagnetic phase transition and the Curie temperature was found to be 219 K for the nanocrystalline La0.7Te0.3Mn0.9Cu0.1O3 sample. Magnetic field dependence magnetization M(H) show the hysteresis loop at 2 K and 50 K confirming the formation of intrinsic ferromagnetic ordering due to Cu doping. [ABSTRACT FROM AUTHOR]

In solar distillation unit major issues is with the lesser rate of distillation. The objective of this present communication is to improve the productivity output of solar still by preheating the saline water with external agencies. This work also promotes in finding the optimal water depth for better productivity and thermal efficiency. In the paper, conventional type single slope solar still (SSSS) has an integrated flat plate collector (FPC) arrangement. Outdoor experimentation has been performed for the active single slope solar still (SSSS) assisted with FPC to find the optimal basin water depth. Investigation has been performed in clear sky conditions on south-facing at an inclination angle of 23° latitude. The experimentation is being performed with varrying the different basin depths (3,6,9,12 cm) for solar still without flat plated collector and another is assisted with it. Various operating parameters have been investigated like hourly distillate output, Different temperatures, coefficients of heat transfer (hew) and (hcw). Result shows that the heat transfer coefficients mainly influenced by basin water depth in the solar still unit. The maximum productivity as well as thermal efficiency for the lower water depth of 3 cm in conventional solar still 0.727 l/day and 45.11% and it increases due to the additional thermal energy supply through FPC from to 1.59 l/day and 57.07% respectively under the same basin conditions. Results obtained at optimized conditions were in close agreement with the predicted responses of theoretical aspects. It is also revealed that nocturnal effect was dominating the responses at higher water depth. [ABSTRACT FROM AUTHOR]

The electrical conduction properties of lithium ferrite Li0.5FeCr1.5O4 have been studied by impedance spectroscopy in the range of 373-450 K. Our study reveals a mixed ionic and electronic conduction with almost equal contributions at 373 K. As temperature increases, the relative contribution of electronic conduction increases and becomes∼57 % at 450 K. The ionic conduction comes from the mobile Li+ ions, whereas, electronic conduction is due to transfer of the 3d-electrons (localized at the metal ions) between Fe3+ and Fe2+ ions. The change of slopes for both the ionic and electronic conductions vs temperature curves at the magnetic ordering temperature TC = 417 K, reveals a strong magneto-electric coupling. The activation energies for the temperatures regions above and below TC are determined to be 0.146eV and 0.134eV for ionic conduction, and 0.161eV and 0.152eV for electronic conduction. Our study has demonstrated the correlation of cation distribution among the tetrahedra and octahedra sites with conduction properties in Li0.5FeCr1.5O4. [ABSTRACT FROM AUTHOR]

Silicon photomultipliers (SiPMs) are gaining popularity over conventional photomultiplier tubes (PMTs) in various radiation detection applications. For this application, it is necessary to optimize the scintillator material and its geometry. In order to develop a compact, low power gamma spectrometry system based on a scintillator coupled SiPM detector, energy deposition in Gd3Ga3Al2O12(Ce) (abbreviated as GGAG(Ce)), NaI(Tl) and CsI(Tl) scintillators of different dimensionswas calculated using Monte Carlo simulation code FLUKA for different gamma energies from 60 keV to 2614 keV. It is observed that energy deposition is highest in GGAG(Ce) followed byCsI(Tl) and NaI(Tl) respectively. By increasing thepath length of the scintillator, energy deposition is seen to increase for energies 662 keV, 1250 keV and 2614 keV. However, for 60 keV, the increase in longitudinal dimension above 3 mm does not affect the energy deposition. Based on the simulation data,GGAG(Ce) scintillator with 3×3×24 mm3 geometry was chosen for making a scintillator coupledSiPM detector. [ABSTRACT FROM AUTHOR]

Robots are robots that are controlled by a software program or electrical circuitry and are programmed to execute sophisticated, often repetitive tasks. Biped robots are fascinating because they resemble human movement in certain ways, leading to the term "humanoids" being used to them. Locomotion refers to an organism's capacity to move from one location to another. It might be self-propelled or reliant on its surroundings. Walking, crawling, swimming, rolling, jumping, and burrowing are some of the most prevalent locomotion techniques. It is more capable than any other sort of robot of performing successfully in a human-oriented setting with excellent harmony. In this study, two situations of uneven terrain walking are investigated. In the first situation, the biped robot is believed to be walking at half the pace of flat terrain walking, while in the second case, the speed of uneven terrain walking is supposed to be the same as flat terrain walking. This dynamic model and the foot construction help a biped robot walk more steadily over rough terrain. [ABSTRACT FROM AUTHOR]

The C1.25Fe1.75O4 ferrite was prepared by chemical co-precipitation and post annealing at 900°C. The nuclear structure (lattice) and magnetic structure were determined by analyzing the Neutron diffraction patterns. The A and B sublattice magnetic moments confirmed ferrimagnetic order in cubic spinel structure. The net moment is comparable to data from dc magnetic measurement. The system exhibited an anomaly below 100 K, where increase of lattice parameter on decreasing the temperature (negative lattice expansion) is accompanying with the decrease of magnetization curve. [ABSTRACT FROM AUTHOR]

With the ever-increasing use of radio frequencies in various industries around the world, we must make sure that these increasing levels of electromagnetic radiation don't cross safe, permissible levels and harm humans. In an effort to tackle this problem, we have developed a portable device that aims to measure the intensity level of radio frequencies with a sufficient level of accuracy. This will enable us to accurately gauge ambient levels of radio frequency radiation. [ABSTRACT FROM AUTHOR]

The characteristic nuclear structure properties of doubly odd 86Rb nucleus has been studied within two-body effective interactions incorporated in a self-consistent quantum mechanical approach known as - Projected Shell Model to test the efficacy of the chosen valence space. The Projected Shell Model (PSM) uses a truncated valence space under the assistance of the deformed mean-field solutions so as to make the calculations feasible. The influence of the high-j orbitals, h11/2 for neutrons and g9/2 for protons on the structure of 86Rb isotope is investigated in the present work by assuming an axial symmetry in the deformed basis. For this isotope, PSM calculations are performed to obtain the yrast line and also the description of the formation of the yrast level structure from multi-quasi-particle configurations. The back-bending in moment of inertia and transition energies have also been calculated and compared with the experimental data. The reduced transition probabilities, i.e., B(E2) and B(M1) for the yrast band are also obtained from the PSM wave functions for the first time, thereby extending an opportunity for the experimentalists to work for this data. [ABSTRACT FROM AUTHOR]

The exposure of human population to natural radioactivity has become an important issue. Natural radioactivity is hazardous to health and is usually determined from 226Ra, 232Th and 40K. These radionuclides emit gamma radiations which on inhalation and ingestion lead to irradiation on human body. The aim of present work was to study the activity concentration and radium equivalent due to 226Ra, 232Th and 40K radionuclides. This study was carried out in soil samples of Shaheed Bhagat Singh District of Punjab, India using gamma ray detector NaI(Tl). Activity concentration of natural radionuclides 226Ra, 232Th and 40K in soil of Shaheed Bhagat Singh District of Punjab varies from 28 Bq/kg to 38 Bq/kg, from 38.2 Bq/kg to 55.4 Bq/kg and from 201 Bq/kg to 376 Bq/kg with average values of 32.2 Bq/kg, 48.8 Bq/kg and 324.3 Bq/kg respectively. Radium equivalent from these radionuclides is found to vary from 96.7 Bq/kg to 139.6 Bq/kg with average value of 124.7 Bq/kg which is less than the safe limit of 370Bq/kg recommended by OECD (Organization for Economic Cooperation and Development). [ABSTRACT FROM AUTHOR]

In our work, we studied the effect of the triphenyl phosphate flame retardant (TPP) on the flammability of polymethyl methacrylate (PMMA) using probe (microthermocouples) and non-disturbing planar laser-induced fluorescence (PLIF) diagnostic methods. Addition of TPP results in a decrease of the burning rate, reduction of the size of the pyrolysis zone, abatement of the heat flux from the flame to the polymer surface, and also decrease in the concentration of OH radicals in the flame, leading to quenching. Thus, the gas-phase effect of the TPP flame retardant on the flammability of the PMMA polymer was demonstrated. [ABSTRACT FROM AUTHOR]

In this paper, we demonstrate the ZnO quantum dot thin film based UV light Photodetector with a different metal electrode. ZnO quantum dot synthesized using a colloidal synthesis method. The prepared ZnO QD thin film is characterized by X-ray diffraction (XRD), Photoluminance (PL), and UV spectroscopy. XRD result confirmed the formation hexagonal structure of ZnO, UV spectroscopy result confirm the bandgap of ZnO quantum dot is 3.25 eV using Tauc plot. Finally, ZnO quantum dot-based thin film is investigated for electrical and optical characteristics using interdigitated metal-semiconductor-metal (MSM) Ag and Au metal electrode. The comparative study of Ag and Au metal electrodes is investigated in terms of I-V characteristics under the dark condition and with a monochromator light at a wavelength of 375 nm with a power density 43µw/cm2. It is found that the ZnO quantum dot-based fabricated photodetector device using Au interdigitated electrode has better electrical and optical performance as compared to Ag electrodes. [ABSTRACT FROM AUTHOR]

In this work heterostructure composed of perovskite BiFeO3 and Cdse quantum dot is reported for Photodetector application. Perovskite BiFeO3 is synthesized using the solid-state route and Cdse quantum dot synthesis using colloidal Nano-synthesis route. The synthesized BiFeO3 and Cdse quantum dot are characterized using characterized by X-ray diffraction (XRD), Photoluminance (PL) spectroscopy and high-resolution scanning electron microscope (HRSEM). XRD result confirmed the formation of the rhombohedral structure of Perovskite BiFeO3 and XRD result of CdSe quantum dot confirmed the formation of cubic zinc blende phase of CdSe Quantum dot. HRSEM image of BiFeO3 and CdSe confirmed the uniform distribution of particles. The BiFeO3/CdSe heterostructure photodetector is fabricated on 1TO coated glass substrate. The photoresponse of the fabricated heterostructure is investigated using a UV light source with 650 µW/cm2 optical power density. [ABSTRACT FROM AUTHOR]