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In the present article, vertically aligned, hexagonal ZnO nanorods (ZNRs) were deposited on fluoride doped tin oxide (FTO) coated glass substrate using hydrothermal route. The as-synthesized ZnO thin film was subsequently annealed at 300 °C and characterized with various characterization techniques such as X-ray diffraction (XRD), Scanning electron microscopy (SEM), and UV–Vis-NIR spectroscopy. The hexagonal wurtzite crystal structure of ZnO thin film was confirmed by XRD pattern and the ZNRs were revealed from the SEM micrographs. The average diameter of ZNRs is 133 nm. Further, we have studied its dye sensitized solar cell performance by using Eosin-Y dye.

Silica aerogel can be produced by using ambient pressure drying (APD) or supercritical drying depending on the required properties and kind of application. Processing time for ambient pressure dried silica aerogels are longer due to the time consuming steps such as hydrolysis and solvent exchange. Considerable decrease in time has been reported by a few research groups by employing shaking during the solvent exchange. We are reporting further reduction in processing time of tetraethoxysilane (TEOS)-based silica aerogel by carrying out the hydrolysis process at elevated temperature. The aerogel obtained in least processing time showed low density (0.066 kg/m3), low thermal conductivity (0.043 W/mK), high specific surface area, and porosity. This shows that elevated temperature hydrolysis does not hamper the desired properties of the product.

The emergence of an electric field controlled memristive effect paves the way for efficient resistive memory and future computing applications. The photo-induced memristive effects provide an additional degree of freedom by utilizing the photonic stimulus. Considering this strategy, the present work reports synthesis, characterization and exploration of the resistive switching (RS) effect of the CdS-sensitized TiO2 nanorod array-based memristive device. The Al/CdS-sensitized TiO2/FTO thin-film device demonstrates the Ultraviolet–Visible (UV–Vis) induced RS behavior and non-volatile memory properties. The memory device shows 103 cyclic switchings and can retain data up to 103 s. The device conduction analysis reveals that the Ohmic, Child's square law and Schottky models were well fitted to the experimental I–V data and responsible for current conduction in the Al/CdS-sensitized TiO2/FTO memory device. The results of the present work are beneficial for several applications that include light-responsive memory, synaptic and sensor devices.

The dielectric relaxation study for the hydrogen bonded binary system of polar liquid N,N-dimethylacetamide in butanol and pentanol, has been carried out at 11 concentrations over the frequ...

Complex dielectric spectra over the frequency range of 10 MHz–20 GHz and FTIR spectra in the region of 4000 cm−1–500 cm−1 of binary mixture of ethylene glycol monobutyl ether with chlorobenzene and...

FTIR and Dielectric relaxation studies on bromobenzene with methoxyethanol and ethoxyethanol binary mixtures have been carried out at eleven concentrations at 303 K. Complex dielectric spectra were...

The frequency dependent dielectric relaxation spectra for binary mixture of chlorobenzene with 2-methoxyethanol and 2-ethoxyethanol at eleven concentrations at 303 K over frequency range 10...

In engineering manufacturing industries, cylindrical grinding process is extensively used for finishing the end product. Nowadays, due to competitive manufacturing environment, these industries are facing a problem of creating world-class products with least manufacturing cost and power requirements. In this work, the optimal process parameters values of cylindrical plunge grinding process are obtained for grinding feed rate, dressing cross feed rate and dressing depth of cut using three different types of multi-point diamond dressers, like needle blade with natural diamond, monocrystalline diamond dresser and chemical vapor deposition dresser using Taguchi-based grey relational analysis. Taguchi’s L9 orthogonal array was used to conduct experiments on CNC angular head grinding machine, and responses like surface finish, grinding ratio and power for grinding cycle were considered. Based on the Taguchi’s grey relational analysis, the optimum levels of grinding parameters were found and significant contribution of these parameters are determined using ANOVA. The optimum levels of the grinding parameters were found out and validated.

Cost effective, simple chemical route has been applied for development of orthorhombic MoO3 for gas sensing application. Opto-structural study confirmed that, the formation of phase pure stable orthorhombic crystal structure with 3.2 eV band gap value. Morphological results reveals the formation of two dimensional nanoplate like surface morphology, which more suitable for gas sensing application. The synthesized MoO3 film is highly selective and 20-fold greater sensitive for detection of NO2 gas in comparison with other gases. As a result, the highest gas sensitivity 71.8% was obtained at 200 °C for 100 ppm of NO2 gas. Overall results indicated that, the synthesized material can suitable candidate for sensitive and selective exposure for NO2 gas.

The dielectric relaxation study for the hydrogen bonded binary system of polar liquid ethyl acetate in 1-butanol and 1-pentanol, has been carried out at 11 concentrations over the frequency range o...

Concentration dependent dielectric constant, relaxation time, excess dielectric constant, excess inverse relaxation time and the effective Kirkwood correlation factor of the binary mixture of methy...

The frequency dependent dielectric relaxation spectra for binary mixture of dimethylacetamide with formamide and dimethylformamide at 11 different concentrations at 30°C over frequency range 10 MHz to 20 GHz is studied. The mixture exhibit a principle dispersion of the Davidson-Cole relaxation type. Dielectric constant (ϵ0), relaxation time (τ), excess dielectric constant (ϵE), excess inverse relaxation time (1/τ)E and Kirkwood correlation factor (g) have been determined and discussed in terms of the effect of NH2 and –CH3 side group on molecular dynamics and intermolecular hydrogen bonds. Conformational analysis of the formation of hydrogen bond is supported by the FTIR study.

Dielectric relaxation study on dimethylacetamide with ethanolamine and dimethylaminoethanol binary mixtures has been carried out at eleven concentrations over the frequency range of 10 MHz to 20 GHz at 30°C using TDR technique. The least squares fit method has been used to obtain the static dielectric constant (ϵ0) and relaxation time (τ). By using these dielectric parameters, the excess permittivity (ϵE), excess inverse relaxation time (1/τ)E and Kirkwood correlation factor (geff) are also obtained for investigating the intermolecular interaction. Conformational analysis of the intermolecular interaction between DMA-ETA and DMA-DMAE systems is supported by the FTIR spectra.

Complex dielectric spectra over the frequency range of 10 MHz to 20 GHz and FTIR spectra in the region of 4000 cm−1 500 cm−1 of binary mixture of ethylene glycol monobutyl ether with methanol were obtained over entire concentration range at 303K. The static dielectric constant (e0) and relaxation time (τ) have been obtained. Using these values the excess permittivity (eE), excess inverse relaxation time (1/τ)E, and Kirkwood correlation factor (geff) were determined. On the basis of these parameters, intermolecular interaction and dynamics of molecules are predicated and conformational of the hydrogen bond is supported by the FTIR.

FTIR and Dielectric relaxation studies on ethylene glycol monomethyl ether with methanol binary mixtures have been carried out at eleven concentrations at 303K. Complex dielectric spectra were obtained in the frequency range of 10 MHz to 20 GHz using TDR. The least squares fit method has been used to obtain the static dielectric constant (e0) and relaxation time (τ). By using these dielectric parameters, the excess permittivity (eE), excess inverse relaxation time (1/τ)E, and Kirkwood correlation factor (geff) are also obtained for investigating the intermolecular interaction. The dielectric parameters show systematic change with concentration and alkyl chain length of alcohols.

The dielectric relaxation study for the hydrogen bonded binary system of polar liquid ethylene glycol ethyl ether and methanol, has been carried out at 11 concentrations over the frequency range of 10 MHz to 20 GHz at 30°C using TDR. The least squares fit method has been used to obtain the static dielectric constant (e0) and relaxation time (τ). By using dielectric parameters the excess permittivity (ɛE), excess inverses relaxation time (1/τ)E, and Kirkwood Correlation factor (geff) are also obtained to explore the hydrogen-bonded interactions. Conformational analysis of the hydrogen bond between the two systems is supported by the FTIR spectra.

The frequency dependent dielectric relaxation spectra for binary mixture of nitrobenzene with butoxyethanol at eleven concentrations at 303K over frequency range 10 MHz to 20 GHz were studied using Time Domain Reflectometry. The mixture exhibits a principle dispersion of the Debye relaxation type. Dielectric constant (e0), relaxation time (τ), excess dielectric constant (eE), excess inverse relaxation time (1/τ)E, and Kirkwood correlation factor (geff) have been determined and discussed in terms of the effect of -OH side group on molecular dynamics and intermolecular bonds. Conformational of the hydrogen bond is studied by the FTIR.

Nano crystalline Mg-Co-Cd-Nd ferrite with composition Mg0.4Co0.2Cd0.4 Nd0.02 Fe1.98O4 was synthesized by sol– gel method followed by microwave sintering technique. The crystal structure, phase purity of all the ferrites prepared under investigation was studied by X-ray powder diffractometer, FTIR spectra, Field emission scanning electron microscopy (FESEM) techniques. X-ray diffraction patterns of all the ferrites show the formation of single-phase cubic spinel structure. The higher frequency absorption band (υ1) corresponding to tetrahedral (A) site observed at 401 cm−1 and lower frequency absorption band (υ2) corresponding to octahedral (B) site observed at 566 cm-1 confirms the formation of well ferrites. From FESEM image, it was concluded that the prepared ferrite is in nano-size range. The formation of desired nano-ferrite in required ratio without any impurity phase was confirmed by EDAX.

Dielectric relaxation study on formamide with dimethylaminoethanol binary mixtures has been carried out at eleven concentrations over the frequency range of 10MHz to 20GHz at 30°C using TDR technique. The least squares fit method has been used to obtain the static dielectric constant (e0) and relaxation time (τ). By using these dielectric parameters, the excess permittivity (eE), excess inverse relaxation time (1/τ)E, Kirkwood correlation factor (geff) and corrective Kirkwood correlation factor (gf) are also obtained for investigating the intermolecular interaction. Conformational analysis of the intermolecular interaction between formamide - dimethylaminoethanol binary systems is supported by the FTIR spectra.

This experimental study aimed to investigate the elevated temperature behavior of glass powder (GP) as a partial replacement of Portland cement. The residual compressive strength is an essential consideration for the sustainability of newly introduced supplementary cementitious material at elevated temperatures. For this study, the powder of waste glass was used to replace portland cement in the proportion of 0%, 10%,20%, and 30%. For fundamental understanding, the compressive strength test was carried out on samples after exposure to high temperature with two different cooling regimes. The experimental result reveals that the mortar mix with cement replaced by 20% GP for both cooling conditions retained more relative residual strength and showed sound behavior compare to the reference sample. The mortar sample with 20% glass powder replacement shows better performance with lower strength loss for both cooling regimes. For air cooling samples, the average strength loss was 27.0% compared to 31.2% of the reference sample. In water cooling samples, the average strength loss was 25.4% compared to the 30.7% reference sample. The two distinct temperature ranges were observed regarding the effect of glass powder replacement on mortar strength under elevated temperature. For temperature above 400 °C average strength loss was 38.62% in the mortar with glass powder and 35.60%in reference sample for water cooling condition. Similarly, for air-cooling samples, the average strength loss was 51.8% compared to 48.90% of the reference sample. Therefore, the lesser strength loss of mortars containing glass powder may be related with their low calcium hydroxide content.

A simple and sensitive, HPTLC method has been developed for the quantitative estimation of felodipine in it’s single component tablet formulation. The separation was carried out on Merck aluminium plates precoated with silica Gel 60 F254 using n -hexane: ethyl acetate in the ratio of 6:4 (v/v) as mobile phase. Felodipine showed Rf value of 0.53 ± 0.027 and was scanned at 366 nm using Camag TLC Scanner 3. The linear regression data for the calibration plot showed a good relationship with r=0.9792. The method was validated for precision and recovery. The limits of detection and quantification were 23.54 and 71.33 ng/spot respectively. The developed method was successfully used for the assay of felodipine tablet formulations. The method is simple, sensitive and precise; it can be used for the routine quality control testing of marketed formulations.

Unfortunately, in the original publication of the article, the Fig. 7 has an oversight. On Y-axis current density is “uA” rather than “mA”. The correct Figure is given below. The authors regret this error.

This paper presents the study of binary mixture of Nitrobenzene (NB) with Toluene (TOL) for eleven different concentrations at room temperature. The determined Dielectric Constant (e0) Density (ρ) and Refractive index (nD) values of binary mixture are used to calculate the excess properties i.e. Excess Dielectric Constant (e0E), Excess Molar Volume (VmE), Excess Refractive Index (nDE) and Excess Molar Refraction (RmE) of mixture over the entire composition range and fitted to the Redlich-Kister equation. The Kirkwood Correlation Factor (geff) and other parameters were used to discuss the information about the orientation of dipoles and the solute-solvent interaction of binary mixture at molecular level over the entire range of concentration.

Dielectric Permittivity Spectra of the binary mixture of Acetonitrile (ACN) with Benzaldehyde (BENZ) have been studied at 11 different concentrations in the frequency range of 10 MHz–50 GHz for four different temperatures (10 °C, 15 °C, 20 °C and 25 °C) using TDR technique. The binary system of ACN-BENZ has been selected to understand the effect of nitrile and aldehyde group on the dielectric parameters and intermolecular interaction. Static Dielectric Constant (e0), Relaxation Time (τ) are obtained for above mentioned temperatures using nonlinear least squares fit method. Density (ρ) and Refractive Index (nD) are also obtained for 30 °C temperature. These parameters are used to calculate the Excess Static Dielectric Constant (e0E), Excess Inverse Relaxation Time (1/τ)E and Excess Molar Volume (VmE) and are fitted to Redlich-Kister equation. The departure in the excess parameters expresses the strength of the molecular connectivities and the existence of intermolecular interaction between unlike molecules. Kirkwood correlation factor, Bruggeman factor and thermodynamic parameters are studied to understand the information about the molecular interactions and orientation behaviour of dipoles after intermolecular interaction. The study of Fourier Transform Infrared Spectroscopy has been carried out to support the dielectric characterization and confirms the intermolecular association between ACN-BENZ binary system.

Laser ignition overcomes the problem of faster degradation of electrodes using high energy required for lean burn and reduced heat loss to the electrodes. A number of investigations have been carried out on laser ignition of gaseous fuels but the work, on laser ignition of liquid fuels is indeed very limited. In present work, a Multi-dimensional CFD model using ANSYS Fluent 17.2 was developed for constant volume combustion chamber (CVCC) to characterize laser ignition combustion phenomenon from the start of plasma formation to end of combustion. The combustion and emission characteristics of gasoline-air mixture ignited by laser-induced spark were studied using numerical simulation. It was predicted from results obtained from numerical results that peak pressure goes on increasing with the increase in equivalence ratios from 0.8 to 1.4. The numerical simulation results obtained were in good agreement with experimental results of literature with 10.6 % percentage error, which demonstrates that the model developed is valid for the combustion process. The trends of the NOX, CO, CO2, emissions were analyzed using a numerical model.

This paper describes the shear behavior of deep beams. The softened truss model theory, which has been successively used for low rise shear walls and torsion, is extended to deep beams. The theory includes effective transverse compressive stress acting on the shear element and softened concrete stress-strain relationship for the concrete behavior. Theoretical shear strengths were compared with experimental result. Examination of the governing equations helps to identify three major factors that affect the shear strength. They are shear span to depth ratio, transverse reinforcement index and longitudinal reinforcement index. Keywords - Deep Beam, Shear strength, Softened truss model, Reinforced Concrete.

We report the magnetoelectric (ME) coupling in lead-free ME composites composed of Metglas (2605SA1) and K[Formula: see text]Na[Formula: see text]NbO3 (KNN) phases. Thickness of the magnetostrictive layers ([Formula: see text] is changed by stacking number of Metglas layers ([Formula: see text]25[Formula: see text][Formula: see text]m for each layer) while KNN is maintained at a fixed thickness ([Formula: see text]300[Formula: see text][Formula: see text]m). As the number of Metglas layers increased, the peak magnitude of [Formula: see text] first increases, reaches a maximum and then decreases afterward. The static magnetic field ([Formula: see text], where [Formula: see text] shows maximum magnitude shift toward a higher value as number of layers increases. The maximum value of [Formula: see text] 91[Formula: see text]mVcm[Formula: see text]Oe[Formula: see text] is observed for optimized thickness ratio of [Formula: see text]/[Formula: see text] 1 (i.e. [Formula: see text] 5 layers) at [Formula: see text] 160[Formula: see text]Oe. The [Formula: see text] is further enhanced by taking advantage of magnetic flux concentration effect of Metglas as a function of its sheet aspect ratio. The present composites can offer promising opportunities of engineering environmental friendly ME laminate for applications in ME devices such as energy harvester and magnetic field sensors.

The dielectric relaxation measurements on binary mixtures of 2-Methoxyethanol, with Ethanol have been carried out for different concentrations at 288 k, 298 k, 308 k, and 318 k using the time domain reflectometry (TDR) over the frequency range from 10 MHz to 20 GHz. The Kirkwood correlation factor and excess dielectric properties were determined and discussed to yield information on the molecular interaction of the systems. The relaxation time is increasing with increasing concentration of Ethanol. The Bruggeman plot shows a deviation from linearity. This deviation was attributed to some sort of molecular interaction which may take place between the 2-Methoxyethanol and Ethanol. The excess static permittivity and excess relaxation time values are negative for system indicating the solute-solvent interaction to exist between 2-methoxyethanol and Ethanol producing a field in such a way that the effective dipole rotation is hindered.

The complex permittivity spectra of mixtures of methanol with 1-hexanol have been measured in the frequency range 10 MHz to 20 GHz using time domain reflectometry at different temperatures 288 K,298 K,308 K and 318 K respectively. The dielectric parameters such as static dielectric constant, relaxation time were obtained using the calibration method based on nonlinear least squares fit method. Using these parameters excess permittivity, excess inverse relaxation time, were determined. It is observed that, the static permittivity decreases with increase in mole fractions of 1-hexanol in methanol whereas the relaxation time increases for the binary system. The excess inverse relaxation time discussed to yield information on the dynamics and molecular structure of the mixture. The excess permittivity confirms the strong interaction between the molecules of methanol and 1-hexanol in the mixture. The study of excess inverse relaxation time of methanol-1-hexanol reveals dipole rotates slowly in methanol rich region.

The importance of measuring the dielectric constant of a liquid lies in the fact that it provides valuable information about intermolecular interaction and dynamics of molecules at molecular levels. In Nitrobenzene (NB) and Chlorobenzene (CB) molecules the charge distribution is shielded and H-bonds do not appear where as in 2-Ethoxyethanol (2-EE) molecules the charge distribution is exposed. In pure nitrobenzene and chlorobenzene spatial correlation between molecules may appear only by means of dipole-dipole interactions. When there is an exposed distribution of charges, there may be very strong intermolecular interaction, however, in shielded distribution relative contribution to neighbor molecules is absent and hence there may be weak intermolecular interaction between the molecules of the liquids. Here the picoseconds time domain reflectometry in reflection mode has been used to obtain complex dielectric spectra epsiv* (omega) = epsiv' - jepsiv" of binary mixture of 2-EE with NB and CB in the frequency range of 10 MHz to 10 GHz at temperatures of 288, 298, 308 and 318 K.

The in vitro degradation of microspheres of polymers of lactic and glycolic acids were investigated by monitoring the mass loss from the device, the molecular weight of the polymer and the morphological changes of the particles with time. Two different sequences of morphological changes were found to be operative, depending upon the polymer from which they were made--one, (I) for the high molecular weight P(DL)LA, and the other, (II) for all PLGAs and the low molecular weight P(DL)LA. Microspheres of category I showed clear evidence of heterogeneous degradation, where the initially dense microsphere developed a hollow interior. Microspheres of category II plasticized on hydration due to reduction in the Tg of the polymer below the incubation temperature of 37 degrees C. There was suppression of release of entrapped globular proteins from microspheres that underwent plasticization (category II), while slow and sustained release was seen from those that did not (category I). It is proposed that plasticization renders the matrix of category II microspheres non-porous, which prevents release by pore-diffusion. The mass loss profiles of PLGA were found to be different from those reported in the literature, in that the rates of mass loss after an initial lag time were not as rapid as has been reported. The experimental conditions used, namely the use, or otherwise, of agitation, is suggested as the reason for these differences and the need to draw a correlation between in vitro experimental conditions and in visa behaviour is emphasized.