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Electrical and thermal conductivity studies play a vital role in the field of science and technology. According to the conductivity terms, materials can be classified in to good conductors, bad conductors, semiconductors and super conductors. In the free electron theory, electron only acts as carrier and carries its energy from one point to another point either natural or forced. In the present investigation, five renal stones are collected from the poor hard working males who are affected with mineral deposition in the urinary tracts. The stones are collected from the hospital by Lithotropic treatment process. Using two- probes method, the electrical conductivities are measured at different temperatures. The thermal conductivity and temperature coefficients are calculated. The results are reported and discussed.

Tri Glycinsulphate with partial substitution of phosphoric acid, namely Tri Glycine Sulpho Phosphate (TGSP) has been grown by slow cooling method. Habit modifications have been observed with change in the concentration of ortho phosphoric acid (H3PO4). Monoclinic structure of the grown crystals has been confirmed using X-ray diffraction analysis. TGSP crystals doped with L – Asparagine were also grown. The doping effect is qualitatively estimated using FTIR analysis. TGA, DTA studies and dielectric measurements were carried out for pure and L-Asparagine doped TGSP crystals to investigate the thermal and electrical properties of the crystals. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

An experimental procedure adopted to prepare the recent Ferroelectric Glycine Phosphite (GPI) single crystal is presented. As the crystal solubility in water depends on temperature, single crystals were grown from fine seed crystals in a saturated solution by employing the slow cooling technique. Transparent, colourless crystals with habit morphology weighing about 8 gm were obtained with in a month. The same procedure was used to grow single crystals with Thiourea doped GPI (TUGPI). Powder X-ray diffraction studies as well as FTIR studies were carried out on both the crystals. The results are discussed in detail.

An experimental procedure adopted to prepare the recent ferroelectric glycine phosphite single crystals is presented. As the crystal solubility in water depends on temperature, single crystals were grown from fine seed crystals in a saturated solution by employing the slow cooling technique. Transparent, colourless crystals with habit morphology weighing about 8 g were obtained within a month. The same procedure was used to grow single crystals with urea (UGPI). Powder X-ray diffraction studies as well as FTIR studies were carried out on both the crystals. The thermal properties of glycine phosphite (GPI) and UGPI across the ferroelectric phase transition temperature has been carried out. The results will be discussed in detail.

Present competitive world is looking for Components with high strength and fatigue resistance finding their applications in aerospace, turbine parts and especially bio-medical devices with high bio-compatibility. Advanced surface engineering techniques are required to produce parts of higher complexities and desirable surface qualities. Laser peening stood first in a row of all various surface treatments of metallic component. This paper discusses about the mechanical properties like hardness and roughness then the surface morphology and the corrosion behaviour of the laser peened titanium samples with and without coating.

Surface Analysis of 4-Chloro N-Methyl 4-Stilbazolium Tosylate Single Crystal

Single crystals of Nd2TiO5 were grown using Optical Floating zone technique in oxygen atmosphere by spontaneous nucleation. Powder X-ray diffraction pattern showed that the grown single crystal is of homogeneous composition. Laue diffraction was recorded in both transmission and backscattering geometries to check the crystal quality. Vibrational properties were analyzed using Raman measurements.

New stilbazolium derivatives chromophores with donor-π-acceptor structure: 2-[2-(4-Diethylamino-phenyl)-vinyl]-1-methyl-pyridinium naphthalene-2-sulfonate (DESNS) have been synthesized via Knoevenagel condensations reaction. Luminescence property of the grown crystal indicates that the DESNS is an excellent orange and red light emitting material. The chemical etching studies made on the surface of DESNS and to assess the perfection of the grown crystals, which reveals that formation of layer growth pattern. Both the values of dielectric constant and dielectric loss of the crystal were calculated by varying the frequencies at ambient temperature. The effective third-order nonlinear optical susceptibility χ(3) of the grown crystal have been investigated by Z-scan technique using He-Ne laser at 632.8nm, which is found to be χ(3) = 3.509× 10−4esu. The negative sign of the nonlinear refractive index n2 = 5.1242×10−12 m2/W indicates that title material exhibits self-defocusing optical nonlinearity.

Silicon based solar cells are still preferable due to its existing technology with inexpensive fabrication cost. However, silicon solar cells are having drawback of weak absorption in longer wavelength due its indirect band gap and needs efficient light trapping in active region. In this paper, we present a design of solar cells based on top anti-reflection coating (ARC) layer and back reflector which is composed of distributed Bragg reflector (DBR) and diffraction grating (GRA) using finite difference time domain (FDTD) method. Simulations show efficient trapping of photon in active region as comparison to reference solar cell. A relative enhancement of cell efficiency ~54 and 60 % is observed for designed solar cells C2 and C3 respectively. This enhancement in performance of solar cells is attributed to the increased absorption and quantum efficiency in red and infrared part of incident solar spectrum.

This paper discusses the growth and properties of Triglycine Sulphate Crystals (TGS) and with L-Asparagine. Doped single crystal was grown by slow-cooling solution growth technique. TGS crystals with 10 wt% of L-Asparagine exhibited prominent morphological changes in the (101) and (001) planes. Lattice parameter values were determined by powder X-ray diffraction analysis. Incorporation of L-Asparagine in TGS crystals has been qualitatively estimated and confirmed by Fourier Transform Infrared (FTIR) spectra. Micro hardness studies also performed for the pure and doped crystals. A morphology diagram is given.

A single crystal of bis-thiourea nickel nitrate (BTNN) doped potassium dihydrogen phosphate (KDP) has been grown from solution at room temperature by a slow evaporation technique. The cell parameters of the grown crystals were determined using single crystal x-ray diffraction analysis. The different functional groups of the grown crystal were confirmed using Fourier transform infrared analysis. The improved optical parameters of the grown crystal have been evaluated in the range of 200–900 nm using UV–visible spectral analysis. The grown crystal was transparent in the entire visible region and the band gap value was found to be 4.96 eV. The influence of BTNN on the third order nonlinear optical properties of KDP crystal has been investigated by means of the Z-scan technique. The second harmonic generation (SHG) efficiency of grown crystal measured using a Nd-YAG laser is 1.98 times higher than that of pure KDP. The third order nonlinear optical susceptibility (χ 3) and nonlinear absorption coefficient (β) of BTNN doped KDP crystal is found to be 1.77 × 10−5 esu and 5.57 × 10−6 cm W−1 respectively. The laser damage threshold (LDT) energy for the grown crystal has been measured by using a Q-switched Nd:YAG laser source. The bis-thiourea nickel nitrate shows authoritative impact on the dielectric properties of doped crystal. The influence of bis-thiourea nickel nitrate on the mechanical behavior of KDP crystal has been investigated using Vickers microhardness intender. The thermal behavior of BTNN doped KDP crystal has been analyzed by TGA/DTA analysis.

Poly(vinyl chloride) (PVC)—poly(butyl methacrylate) (PBMA) blended polymer electrolytes with lithium perchlorate (LiClO4) as the complexing salts are prepared by solution casting technique. The addition of PBMA into PVC matrix is found to induce considerable changes in physical and electrical properties of the polymer electrolytes. Addition of PBMA into PVC matrix is found to increase the conductivity by two orders of magnitude (1.108 × 10−5 S cm−1) when compared with that of the pristine PVC polymer electrolyte (10−7 S cm−1). Structural, thermal, mechanical, morphological, and polymer–salt interactions are ascertained from X-ray diffraction (XRD), thermogravimetry/differential thermal analysis (TG/DTA), mechanical analysis, scanning electron microscope (SEM), and Fourier transform infrared spectroscopy (FTIR) respectively. A thermal stability upto 250 °C is asserted from the TG/DTA analysis. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44939.

The mechanical properties of crystals are evaluated by mechanical testing which reveals certain mechanical characteristics. The fastest and simplest type of mechanical testing is hardness measurement. The Vickers and Knoop microhardness studies have been carried out on 4-methoxy benzaldehyde N-methyl 4-stilbazolium tosylate crystals grown by a slow evaporation technique over a load range of 10–100 g. The Vickers hardness number ( H v ) and the Knoop microhardness number ( H k ) were found to increase with the increase in load. The Meyer's index number ‘ n ’ was calculated from H v . The Young's modulus was calculated using the Knoop hardness values. Hardness anisotropy has been observed in accordance with the orientation of the crystal.

Light-trapping structures are more demanding for optimal light absorption in thin film silicon solar cells. Accordingly, new design engineering of solar cells has been emphasized and found to be effective to achieve improved performance. This paper deals with a design of thin film silicon solar cells and explores the influence of bottom grating and combination of top and bottom (dual) grating as a part of back reflector with a distributed Bragg reflector (DBR). Use of metal layer as a part of back reflector has found to be promising for minimum requirement of DBR pairs. The effect of grating and anti-reflection coating thicknesses are also investigated for absorption enhancement. With optimization, high performance has been achieved from dual grating-based solar cell with a relative enhancement in short-circuit current approximately 68% while it was approximately 55% in case of bottom grating-based solar cell. Our designing efforts show enhanced absorption of light in UV and infrared part of solar spectrum.

Novel organic nonlinear optical material 4-hydroxy-N-methyl 4-stilbazolium besylate has been synthesized and 7 mm × 5 mm × 3 mm size crystals were grown by slow evaporation technique. Single crystal X-ray diffraction analysis reveals that the crystal lattice is monoclinic. From powder X-ray diffraction analysis the diffraction planes have been indexed. Fourier transform infrared spectrum for our sample confirms the presence of functional groups in the grown crystal. Second harmonic efficiency was determined using Kurtz powder method in comparison with urea to confirm the nonlinearity of the material. The results are discussed in detail.

Synthesis of hydroxyapatite (HAP) nano strips was carried out by chemical precipitation method followed by microwave irradiation. The microwave assisted reactions proceed at fast rates. It is found that the presence of the complex reagent EDTA plays an important role in the morphological changes of nanostructure hydroxyapatite. EDTA acts as a hexadentate unit by wrapping itself around the Ca2+ metal ion with, four oxygen and two nitrogen atoms and forms several five member chelate rings. The relative specific surface energies associated with the facets of the crystal determines the shape of the crystal. Scanning electron microscopy revealed the presence of hydroxyapatite nano strips with the range 50-100 nm in EDTA influenced HAP powders. Fourier transform-infrared spectroscopy (FT-IR) result combined with the X-ray diffraction (XRD) indicates the presence of amorphous hydroxyapatite (HAP) in the as-prepared material. X-ray patterns collected on the powder after heat-treatment at 1100 °C for 2 h in air exhibits single phase of HAP. (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Some bimetallic thiocyanate complexes exhibit excellent nonlinear optical properties. Single crystals of one such material Zinc Cadmium Thiocyanate ZnCd(SCN) 4 abbreviated as ZCTC have been grown in Silica gel using gel technique by the process of diffusion. Colorless transparent crystals of size 12 mm × 2 mm × 1.3 mm have been obtained. Structural analysis has been carried out in powder form and for single crystal using X-ray diffractometer. Single crystal X-ray diffraction analysis reveals that the crystal lattice of ZCTC is tetragonal. From powder X-ray diffraction analysis the diffraction planes have been identified and unit cell parameters are determined.

Single crystals of Ca0.9Nd0.1Ti0.9Al0.1O3 (CNTAO) were grown using optical floating zone technique and the grown crystals were characterized by Laue diffraction and powder X-ray diffraction techniques for crystal quality and its composition, respectively. The powder pattern of CNTAO was indexed and refined using GSAS program to an orthorhombic structure with space group Pbnm (#62), a = 5.3832(1), b = 5.4343(1), c = 7.6389(2) Å, V = 223.4677 Å3′, and Z = 4.

In this paper, we report the successful growth of complex compound of zinc iodide with thiocarbamide by slow evaporation method. The single crystal XRD study reveals that the crystal belongs to monoclinic system with centrosymmetric space group and powder XRD analysis shows that the perfect crystalline nature of the crystal. The presence of functional group and element were confirmed from FT-IR and EDAX analysis. Optical absorbance of the grown crystal was studied by UV–Vis spectrophotometer. The optical constants were calculated from the optical absorbance data such as refractive index (n), extinction coefficient (K) and reflectance (R). The optical band gap (Eg) of thiocarbamide zinc iodide crystal is 4.22 eV. The magnetic properties of grown crystal have been determined by Vibrating Sample Magnetometry (VSM). Room temperature magnetization revealed a ferromagnetic behaviour for the grown crystal. The antibacterial and antifungal activities of the title compound were performed by well diffusion method and MIC method against the standard bacteria like Staphylococcus aureus, Escherichia coli, Klebsiella pneumonia and against fungus like Aspergillus niger, Rhizopus sps and Penicillium sps. Thermal behaviour of the crystal has been investigated using thermogravimetric analysis (TGA) and differential thermal analysis (DTA).

In the title molecular salt, C16H10NO+·I−, the dihedral angle between the pyridinium and benzene rings is 6.61 (8)°. In the crystal, the cation is linked to the anion by a C—H...I interaction arising from the activated aromatic C atom adjacent to the N+cation.

An organic nonlinear optical material 2,3-Dimethyl-N-[4-(Nitro) benzylidene] aniline was synthesized by condensation reaction. The single crystals were grown by the slow evaporation technique at room temperature using ethyl acetate as solvent with large in size and having transparent nature. The unit cell parameters were determined and belong to a noncentrosymmetric orthorhombic crystal structure by single crystal X-ray diffraction. The crystalline nature of the synthesized material was recorded by the powder X-ray diffraction pattern. The molecular structure of the grown material was investigated by proton and carbon nuclear magnetic resonance, mass spectrum analysis. Functional groups were identified by the vibration spectrum analysis. The optical absorbance of the grown crystal was ascertained by Ultraviolet–Visible spectrum. Thermal behaviour and stability of the grown material was investigated by thermo gravimetric/differential thermal analysis. The nonlinear optic conversion efficiency was determined by powder technique and found to be 4.08 times greater that of KDP as a standard reference.

A single crystal of 3-acetyl-2-methyl-4-phenylquinolin-1-ium chloride has grown by slow evaporation solution growth technique using ethanol as solvent. The structural, thermal, optical and mechanical property has studied for the grown crystal. Single crystal XRD revealed that the crystal belongs to monoclinic system with space group P2 1 /c. The presences of Functional groups in the crystallized material have confirmed using the FTIR vibrational spectrum. The optical absorbance spectrum recorded from 190 to 1100 nm shows the cut-off wavelength occurs at 371 nm. The material shows its transparency in the entire region of the visible spectrum. The photoluminescence spectrum shows the ultraviolet and blue emission in the crystal. Thermogravimetric and differential thermal analysis reveal the thermal stability of the grown crystal. Etching study shows the grown mechanism and surface features of the crystal. Vickers microhardness studies have carried out on the (01-1) plane to understand the mechanical properties of the grown crystal. The hardness of the title compound increases on increasing the load. The Meyer’s index number ( n ), and the stiffness constants for different loads has calculated and reported.

The molecules of the title compound, C16H18N2, exists in a trans conformation with respect to the C=N bond [1.270 (3) Å]. The least-squares plane of the dimethylamino group makes a dihedral angle of 1.3 (2)° with the ring to which it is attached. The dihedral angle between the two aromatic rings is 11.70 (2)°. The crystal structure features weak C—H...π interactions.

Organic nonlinear optical (NLO) crystal 2-chloro-N-[4-(dimethylamino)benzylidene]aniline (2Cl4DBA) was synthesized and grown by restricted slow evaporation technique at room temperature using acetone as solvent with good degree of transparency. The lattice parameters were determined and found to be noncentrosymmetric orthorhombic system by single crystal X-ray diffraction. The crystalline nature of the synthesized material was recorded by the powder X-ray diffraction pattern. Molecular structure of the grown crystal was investigated by (1)H and (13)C NMR and functional groups were identified by FTIR spectrum analysis. The optical absorbance of the grown crystal was ascertained by recording UV-Visible spectrum. Thermal and physiochemical stability of the grown material was investigated by TG/DTA analysis. SHG efficiency was determined by Kurtz-Perry Powder SHG technique and found to be 4.2 and 1.54 times greater that of standard KDP and urea crystals respectively.

A novel semiorganic nonlinear optical crystal bis (L-glutamine) potassium nitrate (BGPN) grown by slow evaporation technique at ambient temperature. The grown crystal surface has been analyzed by chemical etching and atomic force microscopy (AFM) studies. Amplitude parameters like area roughness, roughness average, valley height, valley depth, peak height, and peak valley height were measured successfully from AFM studies. Etching studies were carried out by various solvents like water, methanol and ethanol. The etching study indicates the occurrence of different types of etch pit patterns like striations and steplike pattern. The laser damage threshold energy has been measured by irradiating laser beam using a Q-switched Nd: YAG laser (1064 nm). Second harmonic generation (SHG) studies have been performed by famous Kurtz powder technique with reference to standard potassium dihydrogen phosphate single crystals (KDP). It is found from this technique that SHG efficiency of BGPN is in comparison to that of standard KDP crystals.

A novel organic nonlinear optical material 4-fluoro 4-nitrostilbene (FONS), with molecular formula (C14H10FNO2) has been synthesized. Using ethyl methyl ketone as solvent, the synthesized material has been repeatedly recrystallized to minimize the impurities and good optical quality single crystals were harvested by slow evaporation method. Single crystal X-ray diffraction analysis reveals that the grown FONS crystal belongs to monoclinic system with noncentrosymmetric space group “P21”. The powder X-ray diffraction pattern of FONS has been recorded. Functional groups of the title compound were confirmed by FTIR and the molecular structure was confirmed by 1H NMR. The UV–vis–NIR absorption study reveals no absorption in the visible region and the cut-off wavelength was found to be at 408 nm. Optical band gap (Eg) of the grown crystal was found to be 3.27 eV and also the optical constants were determined. Thermal behaviour of the FONS has been studied by TGA/DTA analyses. From the mass spectrum, the ratio of compound formation of FONS was analyzed. The NLO property has been confirmed by Kurtz and Perry powder SHG technique and the SHG efficiency of FONS (262 mV) crystal was found to be 12 times greater than that of KDP (21.7 mV).

Ammonium Hydrogen L-tartarte (AMT), an organic nonlinear optical crystal was grown by slow evaporation method at ambient temperature. Solubility, metastable zone width and induction period of Ammonium Hydrogen L-tartarte in aqueous solution were determined. Good quality crystals were selected and characterized by Single crystal XRD, HR-XRD, FT-IR, (1)H NMR, Mass, TGA-DTA, SEM, EDAX, optical and NLO studies. Single crystal XRD analysis revealed that the crystal system belongs to orthorhombic with cell parameters a=7.65A, b=7.85A and c=11.07A. High-resolution-X-ray diffraction (HR-XRD) analysis was carried out to study the crystalline perfection of the grown crystal. (1)H NMR and FTIR spectrum thus confirmed the presence of functional groups of the grown crystal. Molecular mass of AMT was measured accurately by mass spectroscopic analysis. Surface features of the grown crystal were analyzed by SEM, AFM, chemical etching and the presence of elements in the compound was identified by EDAX analysis. Thermal behavior of the grown crystal has been studied by TG/DTA analysis. The recorded UV-Vis-NIR spectrum shows excellent transmission in the region of 190-1100 nm. The Vickers and Knoop's microhardness studies have been carried out on AMT crystals over a range of 10-50 g. Hardness anisotropy has been observed in accordance with the orientation of the crystal. Fluorescence spectral studies were carried in the range of 280-500 nm for the grown crystal. The SHG conversion efficiency and laser damage threshold were measured using an Nd: YAG laser (1064 nm).

Single crystals of L-alanine lithium chloride single crystals were successfully grown using slow evaporation solution growth technique at constant temperature (303K). The formation of the new crystal has been confirmed by single-crystal X-ray diffraction, FT-IR studies. The crystalline perfection was analyzed by high-resolution X-ray diffraction (HRXRD) rocking curve measurements. The powder second harmonic generation (SHG) has been confirmed by Nd: YAG laser. The results have been discussed in detail.

The mechanical properties of crystals are evaluated by mechanical testing which reveals certain surface characteristics. The fastest and simplest type of mechanical testing is hardness measurement. The Vickers and Knoop microhardness studies have been carried out on 4-ethoxy N-methyl 4-stilbazolium besylate crystals grown by slow evaporation technique over a load range of 10-50 g. The Vickers hardness number (Hv) and the Knoop microhardness number (Hk) were found to increase with the increase in load. The Meyer's index number 'n' was calculated from Hv. The Young's modulus was calculated using the Knoop hardness values. Hardness anisotropy has been observed in accordance with the orientation of the crystal. Laser damage threshold studies have been carried out for the crystal using a Q-switched Nd: YAG laser of ns pulses. The surface of the grown crystal was analyzed with etching. The results are discussed in detail.

A new organic nonlinear optical crystal, L-threonine formate (LTF) has been grown using slow evaporation method in the molar ratio 1: 1. Single crystal XRD analysis revealed that the crystal system belongs to tetragonal with cell parameters a=7.86A0, b= 7.86A0 and c= 11.07A0. High -resolution -X-ray diffraction (HR-XRD) analysis was carried out to study the crystalline perfection of the sample. FTIR spectrum was recorded to identify the presence of functional groups of the grown crystal. The SHG efficiency has been tested by the Kurtz powder technique using Nd: YAG laser.

Single crystals of organic nonlinear material urea thiosemicarbazone monohydrate (UTM) have been grown by slow evaporation method. The grown crystals were characterized by single crystal X-ray diffraction analysis reveals that sample crystallized in triclinic system with noncentrosymmetric space group P1. Powder XRD pattern confirmed that grown crystal posses highly crystalline nature. FTIR spectrum was recorded to identify the presence of functional groups and molecular structure was confirmed by (1)H NMR spectrum. Material confirmation of title compound has been performed by using mass spectroscopic analysis. Elemental composition of grown crystal was confirmed by energy-dispersive spectrometry (EDS). To study the crystalline perfection of the grown crystals, high-resolution X-ray diffraction (HR-XRD) study was carried out. Thermogravimetric and differential thermal analyses were employed to understand the thermal and physio-chemical stability of the synthesized compound. UV-Vis-NIR spectrum revealed the transmission properties of the crystal specimen. Relative SHG efficiency is measured by Kurtz and Perry method and found to about 0.89 times that of standard potassium dihydrogen phosphate (KDP) crystals.

A new and efficient semi organic nonlinear optical crystal (NLO) from the amino acid family l -alanine lithium chloride (LAL) has been grown by slow evaporation technique from aqueous solution. The functional groups were identified from NMR spectral studies. Mass spectral analysis shows the molecular ion mass. Dielectric studies has been done for the grown crystal and relative SHG efficiency is measured by Kurtz and Perry method and found to about 0.43 times that of standard potassium dihydrogen phosphate (KDP) crystals. The compound crystallized in non-centrosymmetric space group Pna21. The results have been discussed in detail.

The 3-Hydroxy Benzaldehyde-N-methyl 4-Stilbazolium Tosylate (3- HBST) is a new organic NLO crystal and it is a new derivative in stilbazolium tosylate family. In this work we have synthesized 3-HBST and the single crystal was grown by conventional slow cooling method. The structure and lattice parameters of the grown crystal were determined by the single crystal X-ray diffraction (XRD) technique and it is exhibiting good crystalline nature which is observed from the powder XRD. In order to check the crystalline quality the rocking curve was recorded using multi crystal X-ray diffractometer. The functional groups were identified from both FTIR and NMR spectral analyses. The π–π* and n–π* optical transition energy levels were estimated from the absorption peaks. The NLO property was confirmed by measuring relative SHG efficiency by Kurtz powder test; it shows 24 times higher SHG efficiency than that of urea. In order to test the mechanical stability the Vickers and Knoop micro hardness measurement were carried out and found that the micro hardness number decreases with increasing load. The melting point was determined from Differential Scanning Colorimetry (DSC).

The mechanism of grain growth in heavily arsenic-doped polycrystalline silicon has been investigated by developing a kinetic model. A computer simulation technique has been used to determine the grain boundary self-diffusion of the silicon atoms and hence the grain size for different arsenic concentrations, annealing times and temperatures has been estimated. The evaluated numerical values are compared with the available experimental values. Using this model the grain size distribution in arsenic-doped polysilicon for various values of arsenic concentration, annealing time and temperature has been determined. The results are discussed in detail.

A kinetic model based on thermodynamical concepts has been investigated to determine the grain size and its surface area in heavily arsenic-doped polysilicon for various arsenic concentrations, annealing times and annealing temperatures. Computer simulation technique has been used to determine the grain boundary self-diffusion of silicon atoms. The numerical analysis of our results shows that the grain surface area increases with annealing time and annealing temperature, but decreases with arsenic concentration. Our theoretical predictions have been compared with the available experimental results.

In the title compound, C16H18NO2+·C7H7O3S−·H2O, the dihedral angle between the pyridyl and benzene rings of the pyridinium cation is 0.2 (1)°. The benzene ring of the tosylate anion makes a dihedral angle of 4.8 (2)° with the best mean plane of the pyridinium cation. The pyridinium cation and the tosylate anion are hydrogen bonded to the water molecule, and the crystal packing is further stabilized by intermolecular C—H...O and π–π interactions [centroid–centroid separations of 3.648 (3) and 3.594 (2) Å.

Growth aspects of Ba and Ca doped cadmium mercury thiocyanate (CMTC) single crystals from silica gel by the process of diffusion are discussed. The incorporation of dopants in the crystal has been confirmed by inductively coupled plasma (ICP) analysis. Single crystal X-ray diffraction studies reveal the structures of the doped crystals to be tetragonal implying that the incorporation of the dopants has not changed the structure of the parent crystal. The diffraction planes were identified and indexed by powder diffraction analysis. High-resolution X-ray diffraction analyses were carried out to investigate the crystalline perfection of the grown crystals. The grown crystals were characterized by Fourier transform infrared and transmission spectral analyses. Vickers microhardness studies on the grown crystals reveal that they belong to soft material category. Employing powder Kurtz method, their second harmonic generation efficiencies were measured in comparison with urea.

Magnetic CoFe2-xGaxO4 nanoparticles were successfully synthesised via hydrothermal method. The samples were characterised by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), vibrating sample magnetometer (VSM). The experimental results showed that the CoFe2-xGaxO4 were composed of single phase spinel structure and the average crystallite size is between 42 and 57 nm. The saturation magnetisation (Ms) of the CoFe2-xGaxO4 nanoparticles decreased linearly as the contents of Ga increased for x = 0.2-0.8 which can be used in sensor applications.

The mechanism of grain growth in heavily boron doped polycrystalline silicon has been studied for various boron concentrations, annealing times and annealing temperatures by proposing a kinetic model based on thermodynamical concepts. A computer simulation technique has been used to determine the grain boundary self-diffusion of silicon atoms. Our theoretical predictions have been compared with available experimental reports. This model has been extended to evaluate the grain size distribution in boron doped polysilicon for various dopant concentrations, annealing times and temperatures. The results are discussed in detail.

We have investigated the kinetics of grain growth phenomenon in heavily phosphorus doped polycrystalline silicon for different doping concentrations, annealing times and temperatures, using a model based on the thermodynamical concepts. Explicit expressions for the grain growth rate and the size for normal grain growth have been derived and numerical evaluations have been made using the computer simulation technique. The simulated values have been compared with the experimental observations. The kinetic model has been extended to determine the grain size distribution in polysilicon. The grain size distribution has been presented for various values of phosphorus concentration and different values of time and temperature of annealing. The results are discussed in detail.

The Barium magnesium hydrogen phosphate (BMHP) crystals were grown in sodium meta silicate gel media. The growth processes were done by single diffusion method and double diffusion for different physical and chemical parameters, such as using different gel densities, various concentrations of phosphoric acid and supernatant solutions. The gel pH plays an important role in the formation of different HPO4 species in the phosphoric system. The pH range in which HPO42− ions dominates were considered which in turn is necessary for the growth of BMHP crystals. In the present investigation, BMHP crystals optimum growth parameters were identified. The laser light exposure medium of growth gave better nucleation reduction. The grown crystals were analyzed by XRD, FTIR, TGA, SEM and etching. The results are discussed in detail.

Guanidinium trichloroacetate (GTCA), a novel organic single crystal was grown by a slow evaporation technique. The single crystal X-ray diffraction study revealed that the GTCA crystal belongs to tetragonal crystal system with the space group P41. From the linear optical studies, the lower cut-off wavelength of grown crystal was found at 257[Formula: see text]nm. The luminescent study showed that the GTCA crystal has high degree of luminescence. The single shot laser damage threshold of grown crystal is found to be 2.6[Formula: see text]GW/cm2. The nonlinear refractive index, absorption coefficient and third-order susceptibility were estimated by Z-scan technique. The two independent tensor coefficients [Formula: see text] of the dielectric permittivity were calculated.

The objective of mechanical stress sensor is to measure the applied pressure or provide control standard to the process. In order to accomplish this, most of the stress sensors convert mechanical stress into electronic signal. Ferrites are the best known magnetic semiconductors. This paper brings out the variation in inductance of the micro-inductor made from [Formula: see text] on application of mechanical stress. [Formula: see text] ferrite nanoparticles are synthesized by sol–gel autocombustion technique. The ferrite powder thus obtained is double sintered at 450[Formula: see text]C and 870[Formula: see text]C in a microwave furnace. The X-ray diffraction pattern of the ferrite confirms spinal structure. The frequency spectrum of dielectric constant is done in the range of 100 to 5 MHz frequency. The variation of inductance [Formula: see text]% with applied compressive stress on the micro-inductor made from the ferrite is measured in the range of 0–8 MPa.

The influence of various designing parameters were investigated and explored for high performance solar cells. Single layer grating based solar cell of 50 μm thickness gives maximum efficiency up to 24 % whereas same efficiency is achieved with the use of three bilayers grating based solar cell of 30 μm thickness. Remarkably, bilayer grating based solar cell design not only gives broadband absorption but also enhancement in efficiency with reduced cell thickness requirement. This absorption enhancement is attributed to the high reflection and diffraction from DBR and grating respectively. The obtained short-circuit current were 29.6, 32.9, 34.6 and 36.05 mA/cm2 of 5, 10, 20 and 30 μm cell thicknesses respectively. These presented designing efforts would be helpful to design and realize new generation of solar cells.

The title compound, C16H16FNO3, exists in a trans configuration with respect to the C=N bond [1.258 (2) Å]. The central methoxy O atom deviates from the plane of the attached benzene ring by 0.0911 (14) Å. The dihedral angle between the aromatic rings is 47.58 (11)°. The crystal structure features C—H...N and C—H...O interactions.