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Silicon carbide (SiC), a non-oxide ceramic with superior thermo-mechanical stability, chemical and radiation resistive properties, finds extensive utilization in optical instruments for terrestrial and space applications. However, its inherent porous texture (α-HCP) becomes a deterrent for high-performance optical telescopes, although several techniques of surface alterations over sintered or reaction-bonded SiC are available. In the present work, the physical vapour deposition (PVD) technique is adopted to deposit a thick (∼5 μm) Silicon dioxide (SiO2) clad layer on a sintered and optically polished SiC (SSiC) substrate. SiO2 clad layer coated SSiC (SDO-SSiC) substrate reduces the surface porosity of SSiC which is found to be suitable for optical mirror application. Finally, an Al based reflective and oxides protective coatings are deposited on SiO2 clad layer to achieve reflective behaviour. The surface figure of 75 nm PV (peak-to-valley) and less than 2 nm surface micro-roughness values are achieved which meets the stringent optical telescope specifications for terrestrial and space applications. The structural and nano-mechanical properties of presently developed SiO2 clad layer-based SiC telescopic mirror have been characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-Ray Analysis (EDX), atomic force microscopy (AFM), and nanoindentation techniques. The optical properties are investigated by optical profilometry and wavelength based spectrometric (both in visible and infrared ranges) techniques. Finally, space worthiness studies viz., thermo-vacuum, thermal storage, thermal shock and relative humidity tests have been carried out successfully. The process of cleaning, grinding and polishing at each substrate preparation stage and coatings are also reported comprehensively.

The 92Mo(n,α)89Zr, 97Mo(n,p)97Nb, 148Nd(n,2n)147Nd and 146Nd(n,p)146Pr reaction cross sections with the neutron of energy of 14.54 ± 0.24 MeV have been measured by using the method of activation and off-line γ-ray spectrometry. The neutron was generated from the D-T reaction at the PURNIMA neutron generator of BARC. The 197Au(n,2n)196Au monitor reaction was used for the estimation of neutron flux. The covariance analysis for the uncertainties of the cross sections has been carried out by considering the partial uncertainties of different attributes. The present data have been compared with the literature data, evaluated data and theoretically calculated values from TALYS-1.9 code.

Silicon carbide (SiC) ceramic exhibits several outstanding properties, such as superior chemical and thermal stabilities, high radiation resistance and low thermal expansion, that qualify it as a p...

The 115In(n,2n)114mIn and 197Au(n,2n)196Au reaction cross sections have been measured relative to the 27Al(n,α)24Na monitor reaction at the two different incident neutron energies of 13.520 ± 0.005 MeV and 14.54 ± 0.24 MeV. The neutrons from the D-T fusion reaction at the Purnima neutron generator were used for activation followed by off-line γ-ray spectrometry. The uncertainty propagation and correlation of measured reaction cross sections were estimated using covariance analysis through considering the partial uncertainties in different attributes. The measured reaction cross sections from the present work have been compared with the literature data from EXFOR compilation, ENDF data of various libraries and theoretically calculated values from the TALYS-1.9 code.

The (n,2n) reaction cross sections of cerium isotopes have been experimentally measured at the neutron energy of 13.50 ± 0.15 MeV by using the method of activation and off-line γ-ray spectroscopy. The neutron energy was obtained from the D-T reaction using the Purnima Neutron Generator at BARC. The natCe sample was irradiated along with the gold and indium monitor foils. The cross sections of 140Ce(n,2n)139Ce and 142Ce(n,2n)141Ce reactions were measured by using both the gold and indium as a monitor and then collapsed to get the best values of reactions cross sections. The uncertainties in the measured cross sections of 140Ce(n,2n)139Ce and 142Ce(n,2n)141Ce reactions were determined using covariance analysis by considering uncertainties in various attributes. The measured values from the present work were compared with the literature data based on EXFOR compilation, evaluated data from different libraries and theoretically calculated values from TALYS-1.95 and EMPIRE-3.2.

Cerium (Ce3+)-substituted cobalt–nickel (Co–Ni) ferrite nanostructures of spinel cubic phase with space group Fd$$\bar{3}$$m had been successfully engineered by solution combustion route. The effect of Ce3+ substitution on the structural, morphological, dielectric, and impedance spectroscopic investigations are probed by using X-ray diffraction (XRD), scanning electron microscope (SEM), and impedance analysis, respectively. Rietveld refinement of XRD data reveal that samples exhibit well-crystalline nature with single phase. The microstructural realm with various Ce3+ doping levels has been identified from SEM micrographs. The replacement of Fe3+ by Ce3+ cations has been confirmed by using energy-dispersive analysis of the ferrite samples. The dielectric constant (e′), dielectric loss (tanδ), ac conductivity (σac), and impedance (Z′ and Z″) at room temperature is investigated as a function of frequency, respectively. The variation of dielectric properties e′, tanδ, σac with frequency are explained by Maxwell–Wagner type of interfacial polarization and the hopping of charge between Fe2+ and Fe3+ as well as the dopant ions at B-sites. The decrease in dielectric constant and dielectric loss tangent with frequency follows the phenomenon of Debye’s relaxation. The enhancement in AC conductivity with frequency is proportional to Ce3+ concentration which follows Jonscher law. The complex impedance plots (Z′ vs. Z″) allows to determine the contribution for conductivity either from grain or grain boundary. Complex electric modulus plot (M′ vs. M″) provides the validation to the result drawn from the complex impedance plots. The results indicate the existence of non-Debye type of relaxation in these ferrites. Impedance spectroscopy allows the ferrite materials to estimate electrical properties which arise due to hopping and relaxation phenomena.

The advancement in technology has provided a lot of ease and solved many safety concerns in various fields. It had also catered various applications in automotive sector and has the capability to solve safety issues in order to prevent the occurrence of accidents to a large extent. Accident Prevention of Automobile using Real-time Tracking (APART) system is one such system which uses the real time tracking of all the vehicles and provides a map view containing real-time plots of all registered vehicle to each of the drivers, So that the driver will have prior knowledge of vehicles in its vicinity to avoid the accidents which would predominantly occur at the junctions, fog areas and blind curves, moreover it also increases the fuel efficiency by reducing the braking and accelerating instances. This paper presents a complete overview of APART system comprising of a raspberry pi and a GPS module to send the location to the real-time database and a map development process by using Google API key in order to display the resultant map.

In the present study, synthesis and magnetic property characterization of Ce3+ substituted Co0.5Ni0.5Ce0.01Fe1.99O4 nanoferrites are reported. The synthesis of the sample is via modified solution combustion chemistry route. The influence of Ce3+ on structural and magnetic properties was studied as a function of 60Co gamma ray irradiation dose at the rates of 50kGy and 100kGy. Single phase formation of as synthesized sample was confirmed through X Ray Diffraction (XRD). Structural analysis was carried out by Rietveld refinement. Rietveld refined XRD data was well fitted with a structure of cubic spinel exhibiting space group of Fd3m. The lattice parameter of the studied samples increased due to the formation of Fe2+ ions under the ionizing effect of gamma radiation. Room temperature magnetic properties were explored by Vibration Sample Magnetometry (VSM). It reveals the enhanced saturation magnetization, remanence and magnetic pinning of the sample with Ce3+ substitution and gamma ray irradiation up to 50kGy. Further increase in dose rate at 100kGy has resulted in reduction of the magnetic properties. It is observed that the enhanced magnetic parameters are evidenced in the larger ionic radii Ce3+ substituted Co0.5Ni0.5Ce0.01Fe1.99O4 nanoferrites. These results are important for understanding the stability and performance of the ferrite based devices used near intense high energy radiation sources.

We present the results of the structural, Magnetic and low temperature Mossbauer spectroscopy studies of Co0.5Ni0.5Fe2-(x+y)CexSmyO4 (where x,y = 0.0, 0.01, 0.015 and 0.02) which was prepared by the solution combustion route using mixture of glucose and urea as fuel. The prepared samples were subjected to X-Ray Diffractometer (XRD), Transmission Electron Spectroscopy (TEM), Vibrating Sample Magnetometry (VSM) and Mossbauer Spectroscopy at room temperature and low temperature (15 K) to understand the phase, structure and magnetic behavior of the samples. The results of XRD reveals the formation of a single phase spinel cubic structure with space group Fd 3 m. The crystallite sizes are found to be increasing with increasing Ce3+ and Sm3+ content. This is due to the fact that bigger ionic radii of Ce3+ and Sm3+ replace Fe3+ ions at B site. The lattice parameter is found to be increasing with the increasing Ce3+ and Sm3+ content due to increased internal strain upon doping. The TEM micrographs reveals that the particles almost appear as spherical and agglomerated. Magnetic measurements show that all the obtained samples exhibit higher saturation magnetization (MS), remanence (Mr), coercivity (HC), anisotropy constant (K) and magneton number (ηB). This is due to the increase in A-B super exchange interaction in the samples. Further the increase in HC with the dopant concentration is interpreted as the enhanced magnetic pinning and ferromagnetic behavior in the samples. The room temperature Mossbauer spectra consist of broadened magnetic sextet and paramagnetic quadrupole-split lines. The presence of the magnetic sextet and doublet component on the Mossbauer spectra indicate the presence of superparamagnetic relaxation with a higher TB than the room temperature. The obtained results suggest that the rare earth doped Co-Ni ferrites are potential candidates for microphone applications.

Nanoparticles of Co0.5Ni0.5Fe2−xCexO4 (where x = 0.0, 0.01, 0.015 and 0.02) ferrites are prepared by the modified solution combustion method using a mixture of fuels and are characterized to understand their structural, microstructural and magnetic properties. The X-ray diffraction is used to confirm the formation of a single-phase cubic spinel structure. The average crystallite sizes are calculated using the Scherrer formula and are found to be less than 50 nm. The microstructural features are obtained by the scanning electron microscopy, and the compositional analysis is done by using the energy-dispersive spectroscopy. The transmission electron microscopy (TEM) investigations show that the synthesized ferrites are made up of very fine spherical nanoparticles. The influence of a rare-earth element (Ce3+) on the magnetic properties of the samples was studied using the Mossbauer spectroscopy. The Mossbauer spectroscopy reveals the formation of broadened Zeeman lines and quadrupole-split lines and the presence of the Fe3+ charge state at B sites in the samples. The quadrupole splitting shows that the orientation of the magnetic hyperfine field with respect to the principle axes of the electric field gradient was random. The magnetic hyperfine field values indicate that the A sites have more A-O-B superexchange interactions than the B sites. The coexistence of magnetic sextet and a doublet component on the room-temperature spectra suggests superparamagnetic properties of the nanoparticles. The low-temperature (15 K) Mossbauer spectroscopy explores the paramagnetic relaxation in the nanoparticles. The area under the sextet refers to Fe3+ concentrations in the tetrahedral and octahedral sites of the ferrite. This study confirms that the Ce3+ substitution of Fe3+ only for octahedron sites causes the decrease in Fe-O-Fe arrangement. The effect of Ce3+ doping on the magnetic properties of Co0.5Ni0.5Fe2O4 is examined from the vibrating sample magnetometry (VSM) spectra. Saturation magnetization values are decreased initially and then increased, as result of Ce3+ doping. This can be explained by Neel’s two-sub-lattice model. Further, the value of coercivity is found to be increasing with increasing Ce3+ concentration. The obtained results of M-H loop with improved coercivity (from 851 to 1039 Oe) by Ce3+ doping of Co0.5Ni0.5Fe2O4 demonstrate the usefulness for permanent magnet applications.

Ferrites may contain single domain particles which gets converted into super-paramagnetic state near critical size. To explore the existence of these characteristic feature of ferrites, we have performed magnetization(M-H loop) and Mossbauer spectroscopic studies of Ni2+ substitution effect in Co1-xNixFe2O4 (where x = 0, 0.25, 0.5, 0.75 and 1) nanoparticles were fabricated by solution combustion route using mixture of carbamide and glucose as fuels for the first time. As prepared samples exhibit spinel cubic structure with lattice parameters which decreases linearly with increase in Ni2+ concentration. The M-H loops reveals that saturation magnetization(Ms), coercive field(Hc) remanence magnetization(Mr) and magnetron number(ηB) decreases significantly with increasing Ni2+ substitution. The variation of saturation magnetization has been explained on the basis of Neel's molecular field theory. The coercive field(Hc) is found strongly dependent on the concentration of Ni2+ and decrease of coercivity suggests that the particles have single domain and exhibits superparamagnetic behavior. The Mossbauer spectroscopy shows two ferrimagnetically relaxed Zeeman sextets distribution at room temperature. The dependence of Mossbauer parameters such as isomer shift, quadru pole splitting, line width and hyperfine magnetic field on Ni2+ concentration have been discussed. Hence our results suggest that synthesized materials are potential candidate for power transformer application.

Nanocrystalline Ni1−xZnxFe2O4 (where, x = 0.0, 0.2, 0.4, 0.6, 0.8 & 1) samples were synthesized through solution combustion technique using oxylyl de-hydrazide (ODH) as a fuel and the effect of dopant and its concentration on the structural and magnetic properties was investigated. As-prepared samples were characterized using different characterization techniques such as, XRD, SEM-EDS, TEM and Raman spectroscopy for their phase-purity, crystallinity, surface morphology and elemental composition; also magnetic properties were investigated through EPR, Mossbauer spectroscopy and vibrating sample magnetometer (VSM). Rietveld fitted XRD and Raman studies confirm the formation of cubic spinel structured ferrites and substitution of Zn ion at Ni site without formation of impurity phases. No other structural changes were observed and the structure remains in cubic phase with increase of Zn concentration. SEM and TEM micrographs reveal that the particles are agglomerated and the particles size were found in the nano range. Also good stoichiometric composition was observed in all the compositions of Zn substituted Ni ferrite samples. Magnetic measurements (VSM) reveal that pure Ni ferrites exhibits soft magnetic behaviour. Further the ferromagnetic behaviour suppressed with the substitution of diamagnetic Zn ion and with increase of its concentration in Ni ferrites, which was further evidenced in the Mossbauer spectroscopic results. At room temperature, electronic paramagnetic resonance spectra exhibits a broad resonance signal with Lande's g factor varies from 2.23 to 1.95 with increase in Zn content, which is attributed to spin exchange interactions between Fe3+, Ni2+ and Zn2+ ions also asymmetric EPR spectra was observed. The investigated results show that, Zn substitution has greater impact on the magnetic properties of Ni ferrites due to the diamagnetic nature of Zn, which inturn alters the cationic distribution and the exchange interactions between Ni-Fe and Fe-Fe.

Tri–positive rare earth ions activated alkali heavy metal borate glasses were designed and synthesised using melt–quenching process. Photoluminescence (PL), nonlinear optical (NLO), and optical limiting (OL) attributes of titled glasses have been systematically investigated in order to understand the efficacy of tri–valent europium ions and the obtained results are discussed in detail. The PL attributes were assessed with the blue light pumping. The NLO and OL features were evaluated in 700–1000 nm spectral region using femtosecond laser pulses. The two–photon absorption and nonlinear refractive index coefficients were found to be increased with elevation of Eu2O3 content to higher doping whereas the OL threshold factors exhibited an opposite behaviour. The PL and Judd–Ofelt analysis revealed the glass matrices containing high concertation of tri–valent europium ions are more useful for red lighting applications when excited with blue light. NLO and OL results suggest the strong Eu3+ containing glasses are ideal materials for designing optical limiters of high power to work in near infrared region with femtosecond pulses.

For the first time, we report on the low temperature Mossbauer spectroscopic study of Zn 2+ 0.5 Mn 2+ 0.5 Sm 3+ x Fe 3+ 2−x O 4 (where x = 0.01–0.05) prepared by the modified solution combustion method using a mixture of urea and glucose as a fuel. The Mossbauer spectroscopy at room and low temperatures was applied to understand the magnetic properties of the samples. The room temperature Mossbauer spectroscopy results suggest that the occupation of the octahedral sites by Sm 3+ ions leads to the distortion enhancement of 57 Fe nuclei environments, which leads to an increase in quadrupole splitting Δ values of D2 and D3 doublets. The low temperature Mossbauer spectroscopy results indicate that the presence of Sm 3+ ions in the octahedron sites causes the decrease in the number of Fe–O–Fe chains. The transformation of Mossbauer spectra doublets into Zeeman sextets is accompanied by a significant decrease in the magnitude I M of Mossbauer spectra intensity within the 0–1.2 mm/s velocity range normalized to its value at 300 K. This drop in the temperature dependence of I M allows one to obtain the magnetic phase transition temperature T M from the Mossbauer experiment.

We report the high energy γ-irradiation induced structural transformations in nanocrystalline Mn 1-x Zn x Fe 2 O 4 (x = 0, 0.25, 0.5, 0.75 and 1) samples synthesized by solution combustion method using a mixture of fuels. All samples were exposed to a gamma radiation dose of 50 kGy. The γ-irradiation decomposes the single phase cubic spinel ( Fd-3m ) structure of the samples into new stable phases. The pure MnFe 2 O 4 sample transformed to Mn 2 O 3 and Fe 1-x O phases whereas the pure ZnFe 2 O 4 sample retained its phase. For the samples with intermediate Zn-content γ-irradiation facilitates the formation of stable α-Fe 2 O 3 and ZnFe 2 O 4 phases, along with amorphous MnO phase. The scanning electron micrographs demonstrate the complete change of the sample morphology with fusion of the particles after γ-irradiation. Our results are important for the understanding of the stability and performance of the devices used in various technological applications near intense high energy radiation sources.

Nanocrystalline mixed Ni1-xZnx Fe2O4 (x = 0.0, 0.2, 0.4, 0.6, 0.8 and 1) have been achieved by low temperature self-combustion technique using oxylyldehydrazide (ODH) as fuel. The structural, morphological and dielectric properties were studied using X-ray diffraction (XRD), Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), Raman Spectroscopy and frequency dependant impedance spectroscopy with frequency range from 1 Hz to 107 Hz. The XRD analyses of as prepared samples show single phase cubic spinel structure with Fd-3m space group. The average crystallite size was estimated using Debye-Scherer's formula and was found to be in the range 15–30 nm. FTIR spectra shows two prominent absorption bands, the higher band at tetrahedral (A) sites and the lower band at octahedral (B) site. The Raman peaks above 600 cm−1 correspond to A1g type, involving motions of O atoms in the tetrahedral group (A-site) and the other low frequency peak 241, 335 and 480 represent the characteristics of the octahedral group (B-site) of ferrites. SEM images shows that all the samples have nano crystalline behavior with spherical shape. EDX confirms the constitutional distribution of prepared samples. The dielectric properties such as dielectric constant e′, dielectric loss tangent and ac conductivity were found to be lowest for x = 0.8. The grain and grain boundary contributions in nano ferrites have been explained using Nyquist plot. The prepared mixed ferrites are good material for frequency dependent applications.

This paper describes the fabrication of a four element gas sensor array for monitoring air pollutants, namely CO, CO2, NO2, and SO2. The four micro-heaters share a single suspended SiO2 diaphragm, utilizing thermal proximity to achieve low power consumption (similar to 10 mW for 300 degrees C). Plasma enhanced chemical vapour deposition SiO2 diaphragm is demonstrated to give higher yield compared with thermally grown SiO2. Sensor array elements are fabricated by customizing each element to sense a specific gas, using different sensing materials. Optimized thin films of ZnO, BaTiO3-CuO doped with 1% Ag, WO3, and V2O5 are used for selective sensing of CO, CO2, NO2, and SO2. Four sensors can be independently controlled to operate at different temperatures to get high selectivity for test gases. The sensor array is packaged on Kovar header, and then characterized for gas sensing. It is demonstrated that the sensors exhibit good sensitivity and selectivity. We report a maximum repeatable response to CO(similar to 78.3% for 4.75 ppm), CO2 (65% for 900 ppm), NO2 (similar to 1948.8% for 0.9 ppm), and SO2 (similar to 77% for 3 ppm) at operating temperatures of 330 degrees C, 298 degrees C, 150 degrees C, and 405 degrees C, respectively.

Sc 3+ doped Mn 0.5 Zn 0.5 Sc y Fe 2−y O 4 (y=0.00, 0.01, 0.03 and 0.05) nanoparticles were synthesized by solution combustion method using mixture of fuels were reported for the first time. The mixture of fuels plays an important role in obtaining nano crystalline, single phase present without any heat treatment. X-ray diffraction (XRD) results confirm the formation of the single-phase ferrites which crystallize in cubic spinel structure. The Fourier transform infrared spectra (FTIR) exhibit two prominent bands around 360 cm −1 and 540 cm −1 which are characteristic feature of spinel ferrite. The transmission electron microscope (TEM) micrographs revealed the nanoparticles to be nearly spherical in shape and of fairly uniform size. The room temperature impedance spectra (IS) and vibrating sample magnetometry (VSM) measurements were carried out in order to study the effect of doping (Sc 3+ ) on the characteristic properties of Mn-Zn ferrites. Further, the frequency dependent dielectric constant and dielectric loss were found to decrease with increasing multiple Sc 3+ concentration. Nyquist plot in the complex impedance spectra suggest the existence of multiple electrical responses. Magnetic measurements reveals that saturation magnetization (M s ), remnant magnetization (M r ), magnetic moment (η B ) and magnetic particle size (D m ) increase with Sc 3+ ion concentration up to x=0.03 and then decrease. The values of spin canting angle (α Y-K ) and the magnetic particle size (D m ) are found to be in the range of 68–75° and 10–19 nm respectively with Sc 3+ concentration. The room temperature Mossbauer spectra were fitted with two sextets corresponding to ions at tetrahedral (A-) and octahedral (B-) sites confirms the spinel lattice. The ferromagnetic resonance (FMR) spectra's has shown that high concentration of scandium doping leads to an increase in dipolar interaction and decrease in super exchange interaction.

The structural, infrared absorption and magnetic property transformations in nanocrystalline Mn0.5Zn0.5Fe2O4 samples irradiated with different doses (0, 15, 25 and 50 kGy) of gamma-irradiation were investigated in this work and a mechanism of phase transformation/decomposition is provided based on the metastable nature of the Mn-atoms in the spinel lattice. The nano-powder sample was prepared by solution combustion route and the pellets of the sample were exposed to gamma-radiation. Up to a dose of 25 kGy of gamma-radiation, the sample retained the single phase cubic spinel (Fd-3m) structure, but the disorder in the sample increased. On irradiating the sample with 50 kGy gamma-radiation, the spinel phase decomposed into new stable phases such as alpha-Fe2O3 and ZnFe2O4 phases along with amorphous MnO phase, leading to a change in the surface morphology of the sample. Along with the structural transformations the magnetic properties deteriorated due to breakage of the ferrimagnetic order with higher doses of gamma-irradiation. Our results are important for the understanding of the stability, durability and performance of the Mn-Zn ferrite based devices used in space applications.

Different doses of gamma-radiation can be used to modify the structural and magnetic properties of a host of materials. The Mn0.5Zn0.5Fe2O4 ceramics samples prepared by the solution combustion route were exposed to different doses of gamma-radiation in order to study stability and phase transformations. The creation of defects and building up of strain was observed after medium doses of gamma-irradiation (up to 25 kGy) into the single phase pristine samples. However, after 50 kGy of gamma-irradiation the locally generated heat drives atomic diffusion, as indicated by the morphological changes in the sample. Furthermore, the sample decomposed into two new stable crystalline phases, alpha-Fe2O3 and ZnFe2O4, along with amorphous MnO phase. Besides the structural transformations we have observed the deterioration of magnetic properties at higher doses. Our results are important for understanding the stability and performance of the ferrite based devices used near intense high energy radiation sources.

Developing countries are the most vulnerable to road accidents because of inefficient implementation of traffic rules. There is either lack of awareness about the road safety rules to the automobilist or they simply choose to ignore them. An intelligent system that can automatically respond to road safety rules is proposed in this paper. The system proposed first identifies all the road safety rules to be implemented in the current location of the vehicle upon recognition of the rules, the system alerts the driver. In case of no response by the driver in the way of following the rule, an automated imposition of rules is done. The recognition of the rules is done by sensing the current location through GPS and scanning through the Virtual Traffic Management System for all the rules that are applicable in that region which are predefined. Upon having known all the rules to be followed, the driver is alerted about the rules. Following which, the control signals are sent to control system to orient the functioning along the lines of following the traffic rules thereby automating the response directly by the vehicles.

An attempt is made in this paper to study,’ The Problems and Opportunities of Rural Women Entrepreneurship in India’. Rural women entrepreneurship opportunities and empowerment programme in India significantly increases rural women participation .The participation of rural women significantly advanced process of rural women entrepreneurship development, the process of participation itself was developing. Entrepreneurship development programmes fails more than due to poor participation of rural women’s. The study emphasis the rural women entrepreneur can face so many problems on that basis inclusive rural women entrepreneur participation coupled with suitable opportunities for their betterment. The union government has implemented various schemes and subsides it is a tool to remove sick problems and financial support of rural women entrepreneurship in India. This is a way of overcome all the problems and challenges to rural women entrepreneur, which will enable rural women to realize their full potentials of their life.

Synthesis and study of structural, microstructural and impedance spectroscopic investigation of Co0.5Ni0.5CexSmyFe2-(x+y)O4 (x,y=0.0, 0.01 and 0.02) ferrites prepared by combustion method. As synthesized samples were characterized through PXRD for structure, SEM for morphology and electrical properties by frequency dependent Impedance spectroscopy analysis. PXRD analysis elucidate the phase purity and crystal structure parameters of the synthesized sample. Scanning Electron Microscopy (SEM) images substantiate the homogenous formation of nanoparticles and the EDS analysis confirms the elemental composition of the products. The effect of Ce3+ and Sm3+ doping on the electrical properties of Co-Ni ferrites was studied using dielectric and impedance spectroscopy at room temperature. Dielectric constant, loss tangent is found to decrease with increase in frequency of the applied field and is found to increase with Ce3+ and Sm3+ substitution to Co-Ni ferrites. The frequency dependence of impedance studies is confirms that the conduction in present ferrites is predominantly due to grain boundary mechanism

We report the evidence of structural changes due to high energy gamma irradiation in Mn 0.4 Zn 0.6 Sm x Gd y Fe 2−(x+y) O 4 (where x=y=0.01, 0.02, 0.03, 0.04 and 0.05) ferrites prepared by self-propagating high temperature synthesis method. The structural properties of the as prepared samples and the structural modifications to the samples after gamma irradiation were studied by X-ray diffraction (XRD), Mossbauer spectroscopy and Fourier Transform Infrared (FTIR) Spectroscopy at room temperature. The XRD patterns of the as prepared samples reveal the formation of mixed cubic spinel phase along with small amounts of α-Fe 2 O 3 , SmFeO 3 and/or GdFeO 3 impurity phases. All samples were exposed to gamma radiation dose of 50 kGy originating from a 60 Co source. Our results demonstrate that after gamma irradiation the structure and composition of the various phases in the sample were changed and more stable new phases like ZnFe 2 O 4 , α-Fe 2 O 3 and MnO 2 evolved. As a result the (magnetic) properties of the materials were also altered. Our observation of changes in structural and magnetic properties of the reported ferrites are important for understanding the stability and performance of the materials used in various devices, which are exposed to high energy gamma-rays.

We report the effect of Sm3+ substitution on the structural and magnetic properties of nanocrystalline Mn(0.5)Zn(0.5)SmyFe(2-y)O(4) (y - 0.00, 0.01, 0.03 and 0.05) samples prepared by propellant chemistry route using a mixture of fuels. Rietveld refinement of XRD patterns confirmed the formation of cubic spinel phase with space group Fd (3) over barm. The lattice parameter values decreased with Sm3+ substitution up to y = 0.03, but with a noticeable increase for the sample with y = 0.05. In all the samples, entire amount of Zn2+ and Sm3+ were found to be present at the A and B sites, respectively. A distribution of Mn2+ ions at the tetrahedral (A) and the octahedral (B) sites of the spinel Mn0.5Zn0.5Fe2O4 was observed. The microstructures of the samples were observed using Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM). For all the samples, the average crystallite size decreased with increase in Sm3+ concentration, as determined using Williamson-Hall method. The FTIR spectra showed prominent absorption bands at similar to 540 and similar to 390 cm(-1) corresponding to the stretching vibrations of the metal ion complexes at the tetrahedral (A) and the octahedral (B) sites, respectively. Magnetic properties such as saturation magnetization (M-s), remanence (M-r) and magneton number (eta(B)) were found to decrease, while the coercivity (H-c) and reduced remanence (M-r/M-s) of the samples were found to increase with increasing Sm3+ content. The increase in H-c with increase in Sm3+ concentration is interpreted as the enhanced pinning of the magnetic moments at the magnetic defects created by Sm3+ ions, which is further confirmed by Mossbauer spectroscopy through a nearly constant magnetic hyperfine field. This results in an increase in the magnetic particle size in spite of decreasing average crystallite size. Our work suggests that, Sm3+ substitution can be used to alter the magnetic hardness of Mn-Zn ferrites and to enable them to be used as potential materials for various technological applications. (C) 2016 Elsevier B.V. All rights reserved.

The structural analysis and magnetic investigation Mn1−xZnxFe2O4 with stoichiometry (x=0, 0.1, 0.3, 0.5, 0.7, 0.9 and 1.0) were synthesized by solution combustion method using mixture of fuel this is first of its kind. As synthesized Mn–Zn nanoferrites were characterized by X-ray Diffractometer (XRD), Transmission electron microscopy (TEM) at room temperature. The magnetic domain relaxation was investigated by inductance spectroscopy (IS) and the observed magnetic domain relaxation frequency (fr) was increased with the increase in grain size. The Room temperature magnetic properties were studied using vibrating sample magnetometer (VSM). It was observed that the real and imaginary part of permeability (μ′ and μ″), saturation magnetization (Ms), remanance magnetization (Mr) and magneton number (Mr/Ms) were decreases gradually with increasing Zn2+ concentration. The decrease in the saturation magnetization may be explained as, the Zn2+ concentration increases the relative number of ferric ions on the A sites diminishes and this reduces the A–B interaction. Hence synthesized materials are good for high frequency applications.

Zinc substituted magnesium (Mg–Zn) ferrites with the general formula Mg1−xZnxFe2O4 (x=0.00, 0.25, 0.50, 0.75, and 1.00) were prepared using the solution combustion route. The dried powder after calcination (700 °C for 2 h) was compacted and sintered at 1050 °C for 3 h. The structural, morphological, dielectric and magnetic properties of the sintered ferrites were studied using X-ray diffraction (XRD), scanning electron microscopy (SEM), impedance spectroscopy, and vibration sample magnetometry (VSM). The XRD analysis of sintered samples confirmed that the expected spinel cubic phase was formed for all samples. The crystallite sizes evaluated using Scherre's formula were found to be in the range of 47–80 nm. SEM analysis showed homogeneous grains with a polyhedral structure. The electrical conductivity increased with increasing frequency, which is normal dielectric behavior for such materials. The dielectric constant, dielectric loss tangent, and AC conductivity were found to be lowest for x=0.50. The VSM results showed that the zinc concentration had a significant influence on the saturation magnetization and coercivity.

Solution combustion method was successfully used for the synthesis of nanocrystalline Mn1-xZnxFe2O4 with stoichiometry (x = 0, 0.1, 0.3, 0.5, 0.7, 0.9 and 1.0). The room temperature dielectric studies real and imaginary part of permittivity (epsilon' and epsilon `') were undertaken in the vide frequency range 1 MHz to 1 GHz. It was found that the real part of permittivity (epsilon') is increases with increasing in frequency and it shows a resonance behavior above 1 GHz and at much higher frequencies there is a significant decrease in the loss factor (epsilon `'). The magnetic domain relaxation was investigated by inductance spectroscopy (IS) and the observed magnetic domine relaxation frequency (f(r)) was increased with increase of grain size. It was observed that the real and imaginary part of permeability (mu' and mu `'), saturation magnetization (M-s), remnant magnetization (M-r) and magneton number decreases gradually with increasing Zn2+ concentration. The decrease in the saturation magnetization may be explained as the Zn2+ concentration increases, the relative number of ferric ions on the A sites diminishes and this reduces the A-B interaction.

Nano size Mn0.4Zn0.6SmxFe2−xO4 (x = 0.00, 0.01, 0.02, 0.03, 0.04, and 0.05) ferrites were prepared by solution combustion method. The structural and magnetic properties of samples were characterised by X-ray diffractometer, Fourier transform infrared spectrometer, transmission electron micrographs and magnetic properties at room temperature. The X-ray diffraction patterns and two prominent absorption bands in the frequency range 375–589 cm−1 confirmed the single phase with spinel cubic structure. The average nano crystallite sizes were in best agreements with transmission electron microscope images. Magnetic studies revealed the narrow hysteresis loops of ferrimagnetic nature at room temperature. The values of saturation magnetization (M s ), remanence magnetization (M r ), coercivity (H c ), remanence ratio (M r /M s ), magneton number, anisotropy constant and Yaffet–Kittle angle decreased with the increase in Sm3+ ion concentration was attributed to relative number of ferric ions on the tetrahedral sites diminished and reduced the Sm–Fe interaction.

Nanocrystalline Mn0.4 Zn0.6SmxGdyFe2-(x+y)O4 where x and y = 0.01,0.02,0.03,0.04 and 0.05 were synthesized by Solution combustion method. The as prepared samples were characterized by X-ray diffractometer (XRD), Transmission electron microscopy (TEM) and Vibrating sample Magnetometer (VSM) at room temperature. From the XRD the crystallite size were found increases with the increase of Sm3+-Gd3+ ions concentration while lattice parameter found to decreases. The real and imaginary part of permittivity (e′ and e′′) were undertaken in the wide frequency range 1GHz to 5GHz at room temperature. It is found that the real and imaginary part of permittivity’s are increasing with increasing Sm3+ and Gd3+ concentration. The magnetic behaviour of as synthesized nano ferrites reveals that, the saturation magnetization (MS), remanence magnetization (MR) is increasing with increasing Sm and Gd concentration. The g-value, peak-to-peak linewidth and spin concentration evaluated from EPR spectra correlated with cations occupancy. These electromagnetic properties clearly indicates that the synthesized materials are the good candidates for L and C band frequency.

Nanocrystalline Mn0.4Zn0.6SmxGdyFe2-(x+y)O4 (x = y = 0.01, 0.02, 0.03, 0.04 and 0.05) were synthesized by combustion route. The detailed structural studies were carried out through X-ray diffractometer (XRD), Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM). The results confirms the formation of mixed spine phase with cubic structure due to the distortion created with co-dopants substitution at Fe site in Mn-Zn ferrite lattice. Further, the crystallite size increases with an increase of Sm3+-Gd3+ ions concentration while lattice parameter and lattice strain decreases. Furthermore, the effect of Sm-Gd co-doping in Mn-Zn ferrite on the room temperature electrical (dielectric studies) studies were carried out in the wide frequency range 1 GHz-5 GHz. The magnetic studies were carried out using vibrating sample magnetometer (VSM) under applied magnetic field of 1.5T and also room temperature electron paramagnetic resonance (EPR) spectra's were recorded. From the results of dielectric studies, it shows that the real and imaginary part of permittivities are increasing with variation of Gd3+ and Sm3+ concentration. The magnetic studies reveal the decrease of remnant, saturation magnetization and coercivity with increasing of Sm3+-Gd3+ ion concentration. The g-value, peak-to-peak line width and spin concentration evaluated from EPR spectra correlated with cations occupancy. The electromagnetic properties clearly indicate that these materials are the good candidates which are useful at L and C band frequency. (C) 2015 Elsevier B.V. All rights reserved.

The changes in structure, infrared absorption and magnetic property of nanocrystalline Mn0.5Zn0.5SmxFe2-xO4 (x = 0.01, 0.03 and 0.05) ceramics were studied after different doses (0, 15 and 25 kGy) of γ-irradiation. The samples were prepared by solution combustion route. We observed that up to the highest studied dose (25 kGy) of γ-irradiation all the samples retain the cubic spinel (Fd-3m) structure as of the pristine samples, however, the lattice parameter decreases. Furthermore, we observed the metastability of Sm (and Mn) atoms at the octahedral sites. By Sm3+ doping the saturation magnetization of the pristine samples decreases, but the magnetic coercivity increases drastically, indicating enhancement of magnetic anisotropy. After γ-irradiation the magnetic anisotropy vanishes completely and the sample behaves super-paramagnetically with a small variation in saturation magnetization. Our results are important to understand the behavior and stability of the magnetic hardness created by Sm3+ doping in soft magnetic Mn–Zn ferrite ceramics.

Few years back four wheeler performed the same in all the terrain, which led to traction loss, reduced efficiency and more wear on machine parts. The new age technology brought different profiles of engine output, that is normal, economy and sports. These profiles brought better performance, drivability and safety. Now that humans want to wander off into different terrains, drive on icy roads, snow and even take the vehicle to beaches and deserts, there came a requirement to provide the best performance in those cases too. Then came the various profiles for different terrains such as snow, sand and mud. There are lots of work around to attain better drivability, safety and performance in these terrains, we have to tackle the issue through the Engine control unit (ECU) to attain the better control on the torque output.

Memory module in any automotive microcontroller is of crucial importance as it stores fast changing data of ECUs and stores important information about the Car, To ensure that the flash memory is robust and can be deployed in the field production, a framework is developed to test the Robustness of FEE. The test setup simulates all possible conditions where information stored in Flash memory can be compromised. This paper aims to detect the faults in Flash Driver programming, by running the code in hardware. This setup can be used to test and increase the Robustness of FEE module in Automotive Micro-controllers.

Nano crystalline spinel ferrites of Co0.5Ni0.5CexFe2−xO4 (x=0.01, 0.015, 0.02, 0.025 and 0.03) was prepared by modified solution combustion method using a mixture of fuels for the first time. The influence of rare earth Ce3+ substitution at the Fe3+ site on the structural, microstructural and dielectric properties of Co0.5Ni0.5CexFe2-xO4 was investigated. The X-ray diffraction (XRD) studies confirmed the formation of monophasic nano crystalline samples without any secondary phases. The crystallite size decreases and density increases with the increases of Ce3+ contents. Surface morphology was studied through Scanning Electron Microscopy (SEM). Dielectric properties of these ferrites have been studied at room temperature using impedance analyzer in the frequency range up to 20 MHz. The effect of frequency and composition on dielectric constant (e’), dielectric loss (tanδ) and ac conductivity (σac) have been discussed in terms of hopping of charge carriers (Fe2+↔Fe3+). The decrease in dielectric loss with frequency follows Debye’s relaxation phenomena. Both the variation in tan loss and dielectric loss with frequency shows a similar. AC conductivity increases with the increases of frequency which directly proportional to concentration of Ce3+ ions follows Jonscher law. These Cerium doped Cobalt-nickel ferrites are very helpful for automotive applications.

Today, air pollution is of major concern. Measuring and monitoring the concentration of pollutants is a major task. Envirobat2.1 is an air quality monitoring device built using commercially available sensors. This device offers cost effective, low power, wireless, efficient and portable features. As an added advantage, the real time data from the globally placed Envirobat2.1 can be accessed by the user through their smart phones as an application of IoT. The device has the capability to sense atmospheric pressure, temperature, humidity, CO 2 , CO, NO 2 , dust particles.

For the first time, we report the effect of high energy gamma irradiation induced structural and magnetic properties of nanocrystalline Mn0.5Zn0.5ScyFe2-yO4 (y = 0.01, 0.03 and 0.05) samples synthesized by solution combustion method using a mixture of fuels. All samples were exposed to a dose of 25 kGy gamma radiations originating from a 60Co source. The as prepared samples and the samples after gamma irradiation were characterized by X-ray diffraction, Fourier transform Infrared spectroscopy and vibrating sample magnetometry at RT. The XRD results reveal that all the pristine samples have shown single phase cubic structure before and after gamma irradiation. The lattice parameter increases on increasing Sc3+ content after gamma irradiation. FTIR reveals that, after gamma irradiation the absorption peaks are shifted to higher frequency. In M-H loops, we observe decrease in saturation magnetization, remnant and coercivity of the samples due to breaking of ferrimagnetic ordering, when a high energy gamma ra...

Magnesium–zinc ferrite (Mg 0.5 Zn 0.5 Fe 2 O 4 ) powder was prepared by a solution combustion method using a mixture of sugar and urea as fuel. To understand the effect of size and crystallinity on its magnetic properties, combustion derived ferrite powder was subjected to calcination at different temperatures in an ambient atmosphere. The powder X-ray diffraction data of calcined samples was used to determine the effect of calcination on phase formation and crystallite size. The average crystallite size of single phase cubic spinel ferrite nanoparticles was found to increase with an increase in calcination temperature. Transmission electron microscopy images showed a uniform particle size distribution with average particle sizes varying in the range of 30–124 nm. Magnetic properties were found to be affected by particle size; we observed a linear relationship between the saturation magnetization and particle size. Low values of squareness ratio and coercivity implied the superparamagnetic nature of the samples.

Various morphologies of Eu3+ activated gadolinium oxide have been prepared by hydrothermal method using hexadecylamine (HDA) as surfactant at different experimental conditions. The powder X-ray diffraction studies reveal as-formed product is hexagonal Gd(OH)(3):Eu3+ phase and subsequent heat treatment at 350 and 600 degrees C transforms to monoclinic GdOOH:Eu3+ and cubic Gd2O3:Eu3+ phases respectively. SEM pictures of without surfactant show irregular shaped rods along with flakes. However, in the presence of HDA surfactant, the particles are converted into rods of various sizes. The temperature dependent morphological evolution of Gd2O3:Eu3+ without and with HDA surfactant is studied. TEM micrographs of Gd(OH)(3):Eu3+ sample with HDA confirms smooth nanorods with various diameters in the range 20-100 nm. FTIR studies reveal that HDA surfactant plays an important role in conversion of cubic to hexagonal phases. Among these three phases, cubic phase Gd2O3:Eu3+ (lambda(ex) = 254 nm) show red emission at 612 nm corresponding to D-5(0)-> F-7(2) and is more efficient host than the monoclinic counterpart. The band gap for hexagonal Gd(OH)(3):Eu3+ is more when compared to monoclinic GdOOH:Eu3+ and cubic Gd2O3:Eu3+. (C) 2013 Elsevier B. V. All rights reserved.