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Trivalent samarium activated β-Wollastonite (β-CaSiO3:Sm3+) nanostructured phosphor powders have been synthesized by modified sol-gel method at various concentrations (0.0, 0.2, 0.4, 0.6, 0.8 and 1 mol %) employing rice husk ash (RHA) and eggshell (ES) as the precursors for SiO2 and CaO respectively. The powder x-ray diffraction peaks disclose structure of sintered samples as monoclinic structure with space group P1 21/c1. The average crystallite sizes were determined by Debye scherrer's formula in the range of 26–34 nm. The average particle size was 84.5 nm found from TEM images. The photoluminescence excitation (PLE) spectra recorded high intensity peak at 400 nm was owing to 6H5/2 → 4K11/2 transition. The emission (PL) spectra of prepared samples exhibit intense orange–red color emission peak at 602 nm due to 4G5/2 → 6H7/2 transition. All the prepared samples emission tuned towards white region of the CIE diagram with the increment of Sm3+ content. This new nanostructured phosphor material could be a probable candidate for white light display and solid-state lighting (SSL) applications.

Objectives To study the determinants of locoregional control (LRC) on stage I/II oral squamous cell carcinoma (OSCC) classified by AJCC 8th edition. Methods Retrospective analysis from 296 patients of pT1-2N0 oral OSCC treated with surgery (wide local excision and selective neck dissection). Those receiving adjuvant therapy were excluded. Multivariate analysis was performed for impact of adverse pathological features (APFs) on LRC. Results In stage I, LRC was impacted by perineural invasion (PNI) (HR 7.72, p = 0.010, 95% CI 1.64–36.26) and moderate/poor differentiation (MD/PD) (HR 3.04, p = 0.049, 95% CI 0.99–9.25). In stage II, LRC was impacted by depth of invasion (DOI) (HR 1.59, p = 0.014, 95% CI 1.099–2.32), PNI (HR = 2.86, p = 0.005, 95% CI 1.36–5.98). Combined MD/PD and PNI were associated with worse LRC than either feature individually (HR = 4.12, p Conclusion PNI and differentiation accurately predict LRC in AJCC 8th edition classified stage I/II OSCC. PNI was a stronger predictor of locoregional failure than DOI in stage II disease. By incorporating these parameters, we can improve precision in staging of early OSCC and identify potential candidates for treatment escalation to improve outcomes.

We present a proof-of-concept “on-off” detection scheme, which uses gadolinium phthalocyanine (GdTcPc)-grafted silica nanoparticles as paramagnetic centers, capable of modifying the transverse relaxation time (T2) of water protons in solution. A DNA strand (as probe) was conjugated to the GdTcPc to act as a recognition element. In the presence of the target DNA, which was complementary to the probe, an increase in the T2 value was detected, with magnitude proportional to the target DNA concentration. The linear range was observed from 30 to 140 nM, with limit of detection of 15 nM. The developed nuclear relaxation-based detection scheme is shown to be a simple, fast and selective method to detect DNA and could be useful in point-of-care diagnostic applications.

In the present technologically advanced era, non-linear optical materials especially organic derivatives are in the limelight due to their fast response in electro-optic switches and high nonlinear efficiency. Therefore, with respect to this behaviour, single crystals of L-argininium Bis(trifluoroacetate) (here in after called LABTF) an organic material was grown by slow evaporation solution growth technique. The grown single crystal was subjected to single crystal X-Ray diffractometer to validate its chemical structure and compound formation. The titled compound crystallizes into an asymmetric entity that comprises of one divalent L-argininium cation and two monovalent trifluoroacetic anion. All the intermolecular hydrogen bonds present in the LABTF crystal structure are investigated by 3D molecular Hirshfeld surface analysis and their relative involvements are disintegrated using 2D fingerprint plots. Further, the crystalline perfection assessment was performed using high-resolution X-Ray diffractometer which divulges the absence of structural grain boundaries in the obtained crystal. Thermal transport parameters of the titled compound were measured through Photoacoustic spectroscopy. The shock strength above which the crystal induces damage was found by the shock damage threshold technique. In addition, mechanical property related parameters such as hardness, stiffness and Young's Modulus were evaluated using the nanoindentation technique. These mechanical parameters resolve the reliability of devices and it can be enhanced by improving the crystal quality.

In the contemporary days, non-linear optical materials (NLO) are getting higher attention as per the increasing demand in optical communication and data storage technology. Consequently, they explore various physical properties of the NLO material for their industrial applications. In current report, l-arginine p-nitrobenzoate monohydrate (LANB) single crystals were obtained by adopting slow cooling technique. The structural confirmation of grown single crystal was carried out using single crystal X-Ray diffractometer. Presence of strain within single crystal was deduced using Hall–Williamson relation. Various defects associated within single crystal were assessed using high resolution XRD. Additionally, its crystalline quality was again confirmed by time resolved photoluminescence spectroscopy (TRPL). Using transmission spectra, the cut off wavelength and band gap of the host material was determined to be nearly 420 nm and 2.9 eV respectively. The dielectric property has been recorded by varying the frequency ranging from 50 Hz to 100 kHz. The curve suggests that dielectric loss value is less at high frequency ensures the suitability of crystal in photonics and NLO based devices. The laser damage threshold values were also measured for single and multiple shots. Thermal parameters of the titled compound were calculated using PPE. In photoconductivity measurement, negative photoconductivity has been observed in titled compound. Microhardness studies were also performed on single crystal to explore its mechanical properties.

This paper discusses the synthesis of undoped ZnO, 2 mol% Dy doped ZnO, 2 mol% Er doped ZnO and 1 mol% Dy,Er co-doped ZnO nanoparticles by simple combustion technique and the characterization of their structural, morphological, magnetic and optical properties by X-ray diffraction (XRD), X-Ray Photoelectron Spectroscopy(XPS), Field Emission Scanning Electron Microscope (FESEM), High Resolution Transmission Electron Microscope (HRTEM), Diffuse Reflectance Spectroscope (DRS), Vibrating Sample Magnetometer (VSM) and Photoluminescence(PL). All samples are of hexagonal wurzite type structure which was found from XRD analysis. The effects of annealing on morphology and luminescence emission wavelengths were noticed in FESEM and PL, respectively. As-prepared sample displayed spherical morphology and annealed co-doped sample showed interwoven hexagonal stacking like morphology. VSM revealed the room temperature ferromagnetism in doped samples. The photoluminescence under the UV and IR excitations was observed in experiment. The as-prepared samples had violet region emission at the 325 nm excitation. The annealed samples had green region emission under the same excitation. Due to the annealing effect, the enhancement of upconversion luminescence intensity in co-doped sample in green (535 nm) and red (665 nm) regions was observed at the 980 nm excitation.

This work reports the synthesis of varied shaped Cu2ZnSnS4 (CZTS) nano inks in a most stable kesterite phase via a hot injection colloidal route. CZTS nanoparticles of varied shape were synthesized by using various capping ligands with the introduction of butylamine as a new capping ligand and two different sulfur precursors respectively. The shape of the as-synthesized kesterite CZTS nanocrystals can be well controlled in the form of nanofibers, spherical nanoparticles, nano hexagons, nanotriangles, and nanodiscs. A detailed analysis of the effects of various capping ligand and sulfur source on reaction conditions to obtain pure phase kesterite CZTS nanocrystals for different shapes is explained using LaMer's diagram. It has been found that the choice of sulfur precursor also plays an important role in determining the symmetry and orientation of the plane of the CZTS nanocrystals. Due to different morphology and capping ligands present on the surface, diverse surface properties were obtained which was confirmed by contact angle measurements. The variation in the band gap was also found with changes in morphology of kesterite phased CZTS nanoparticles. Due to variations obtained in band gap, changes in I-V characteristics were also observed which may leads different CZTS nanoparticles to have their potential applications in different regime other than photovoltaics like sensors, photocatalysis etc.

Particulate matter (PM) deposition on leaves adversely affects physical, chemical and biological nature of agricultural crops resulting in their loss of productivity and yield. Wheat being a staple food in major parts of Northern India and around the World, has been selected for research purpose by designing a study to explore the probable effects of PM deposition on wheat leaves and wheat crops to ensure the food security. PM5 (Particulate matter with aerodynamic diameter 1.20–1.40) and CIR (>0.70–0.80) for both PM5 and leaf_DDPM were observed. The size distribution of individual particles for both PM5(#194 particles) and Leaf_DDPM(#657 particles) revealed that Surface Equivalent Radius (SER) and Volume Equivalent Radius (VER) of particles observed to be 0.40–0.80 μm while surface area to be 0–1 μm2. These particles may easily block stomatal openings (with typical diameter range: 42–51 μm) of wheat leaves and damage internal leaf tissues while particle VER determines the interaction of incoming solar radiation with leaf surfaces. Average PM5 concentrations ± Standard deviations (μg/m3) were reported to be 231.05 ± 113.03. The XRF (X-Ray Fluorescence) spectrometer analysis of bulk PM5 revealed the concentrations of non-carbonaceous elements (μg/m3) as N (67.34 ± 16.09), Si (27.44 ± 11.01), Al (7.79 ± 3.37), S (3.88 ± 2.24), Na (2.29 ± 0.94), Mg (1.65 ± 0.62), K (0.51 ± 0.26), Ca (0.60 ± 0.26), Fe (0.54 ± 0.26), Cr (1.10 ± 0.70), Zn (0.05 ± 0.03), P (0.10 ± 0.03), Cu (0.07 ± 0.06). The dominant elemental oxides were calculated as SiO2, Al2O3, SO 4 2 − , Na2O, MgO, K2O, CaO, Fe2O3, Cr2O3, ZnO, P2O5, Cu2O with variable concentrations. In high humid conditions, with relative humidity (~85%) during the vegetative and flowering growth stages of wheat crops, presence of C and S rich acidic and hygroscopic particles may cause the corrosion of wheat leaves that ultimately affect the wheat crops.

Today the fundamental aspect of the researchers is to explore maximum physical properties of the material for device fabrication. In the present article, single crystal X-ray diffraction has been carried out to verify the formation of the synthesized compound. In addition to that, powder X-ray diffraction has been performed to obtain diffraction pattern of l -Prolinium Picrate single crystal. The strain present inside the single crystal was measured using Hall-Williamson equation from PXRD measurements. The dark current and photon current was obtained from photoconductivity technique whose plot depicted that the sample was negative photoconducting material. Optical homogeneity of the single crystal was analyzed using birefringence technique. Its resistance towards Nd: YAG laser was scrutinized for l -Prolinium Picrate single crystal by applying 1 pulse per second. Different thermal parameters like thermal conductivity, thermal diffusivity, thermal effusivity and specific heat were computed using photo-pyroelectric technique. Solid state parameters were calculated from Clausius Mossotti relation by taking structural information of the title compound. Also, optical parameters like refractive index, reflectance etc were calculated through UV–Vis–NIR analysis.

Tin oxide nanomaterials were prepared by efficient and cost effective co-precipitation method at different sintering temperatures. Structural, thermal and optical properties of the final product indicate that change of sintering temperature had an impact. Sintering temperature has minor influence on crystallite size of the samples. With the decrease in crystallite size, the surface area increases; the degradation efficiency increases with adsorption which is directly proportional to surface area. The absorption peak red shifted against the sintering temperature which denotes it moves to visible region with low bandgap. The Differential Thermal Analysis endothermic peak points out the decomposition of tin oxalate into tin oxide. The commonly available textile colorant methylene blue was degraded using prepared SnO2 as a photocatalyst in visible light. The tin oxide which has low crystallite size gives highest methylene blue photodegradation than others due to its low recombination rate, high surface area. Discussed the possible mechanism for the formation of organic dye degradation strong oxidant OH.

The present work depicts the spatial and temporal variations in chemical characteristics and sources of PM2.5 and PM10 over Indo Gangetic Plain (IGP) of India from January 2015 to December 2016. PM2.5 and PM10 samples were collected at three typical urban sites of Delhi, Varanasi, and Kolkata of IGP, India and characterized to evaluate their chemical components. The average concentrations of PM2.5 at Delhi, Varanasi, and Kolkata were 135 ± 64, 99 ± 33, and 116 ± 38 μg m−3, respectively. Whereas the average concentrations of PM10 over Delhi, Varanasi, and Kolkata were 242 ± 95, 257 ± 90, and 179 ± 77 μg m−3, respectively. Source apportionment was carried out using the three receptor models i.e. Principal Component Analysis-Absolute Principal Component Score (PCA-APCS), UNMIX, and Positive Matrix Factorization (PMF), implemented on the same data sets to obtain the conjointly validated results. All the models identified that vehicular emissions, secondary aerosols, biomass burning, and soil dust were the dominant sources of PM2.5 and PM10 over IGP, India. Hybrid receptor models revealed the presence of strong local emission sources as well as traversing of pollutants from the parts of Pakistan, Punjab, Haryana, Rajasthan, Uttar Pradesh, Bihar, and Bangladesh.

A novel monomer (terpolymer) was prepared by mixing of 2-amino-6-nitro-benzimidazole, 2,5-diaminophenol and formaldehyde. Based on the impressive material utilities and therapeutic potential, Cu2+, Ni2+, Co2+ and Zn2+ metal ions were mixed with terpolymer to form different metal chelates. UVVis., IR, 1H NMR, ESR spectral data analysis showed that the prepared metal chelates were of square planar geometry. The molecular mass of polymer was determined using gel permeation chromatography technique. Thermo gravimetric technique was utilized to measure the thermal withstanding ability of terpolymer chelates. The electron transfer mechanism of the metal complexes was investigated by the aid of cyclic voltammetry. The prepared compounds were also screened for antimicrobial efficiency against bacterial strains (B. subtilis, E. coli and S. aureus) and fungal strains (C. albicans, A. niger and A. flavus). The observed results indicated that the chelates showed greater antimicrobial efficiencies than terpolymer ligand. Furthermore, the SOD biomimetic activity of prepared metal chelates was accessed and copper complex was found to possess high antioxidant potential with IC50 value of 0.94 µM. Antituberculosis capacities of terpolymer and its metal chelates was assessed against M. tuberculosis H37Rv strain using MABA assay protocol. Copper complex was found to possess good antitubercular activity with MIC value of 6.20 mg/mL. Molecular docking study was conducted to assess the target for antitubercular activity. It was found that copper complex could be a potent inhibitor of pantothenate synthetase enzyme (a potential target for development of antitubercular drug) of M.tuberculosis with binding energy of -9.8 kcal/mol. Overall copper complex showed good antimicrobial, antioxidant and antitubercular activity when compared to other metal complexes and terpolymer ligand.

Carbonaceous components [organic carbon (OC), elemental carbon (EC), water soluble organic carbon (WSOC), primary organic carbon (POC), secondary organic carbon (SOC) and carbonaceous aerosols (CAs)] and major and trace elements (Na, Mg, Ca, Al, Fe, Ti, Cl, P, S, K, Cr, Ni, Cu, Zn, Mo and B) of PM10 were studied over the eastern Himalayan high altitude station [Darjeeling: 27.01°N and 88.15°E, 2200 m average mean sea level (amsl)] during winter 2018–19 (December 2018–February 2019). The carbonaceous aerosols/species (CAs) contributed to ~23% of PM10 mass concentration, whereas major and trace elements accounted for 10% of PM10. During the entire study period, the average concentrations of PM10, OC, EC, WSOC, POC, SOC and CAs were recorded as 48 ± 16 μg m−3, 5.39 ± 1.84 μg m−3, 2.60 ± 0.94 μg m−3, 3.87 ± 1.18 μg m−3, 3.40 ± 1.23 μg m−3, 1.99 ± 1.03 μg m−3 and 11.21 ± 3.78 μg m−3, respectively. Significant positive correlation between OC & EC and OC & WSOC have been observed which are indicating their common sources. WSOC/OC ratio was estimated to be 0.71 suggesting that the biomass burning is one of the major sources of carbonaceous aerosols at Darjeeling during winter. The significant positive correlation of PM10 with crustal elements (Al, Fe, Ca, Mg and Ti) as well as the correlation of Al with other crustal elements (Fe, Ca, Mg and Ti) indicates the abundance of mineral dust at the sampling site. Principal component analysis (PCA) identified the contribution of crustal/soil dust, biomass + coal burning, vehicular emissions and solid waste to the PM10 over the eastern Himalayan region of India.

Ammonium d , l -Tartrate (AMT) single crystal for optical and photonic device application was analyzed with different characterization studies. The AMT crystal was grown by low cost conventional solution growth technique. The unit cell parameters were obtained from single crystal XRD analysis and the crystal system is confirmed to be orthorhombic with noncentrosymmetric space group P2 1 2 1 2 1 . The crystalline perfection evaluated by high resolution X-ray diffractometry (HRXRD) enumerates the quality of the crystal is good. The optical transparency window of AMT crystal has 78% transmittance from 234 nm to 1100 nm region and has lower cut-off wavelength of 234 nm was analyzed by UV–visible spectral studies. The hardness number (H v ) , yield strength (σ y ) and elastic stiffness constant (C 11 ) were evaluated from the hardness data using Vickers hardness tester. Dielectric study indicates the moderate dielectric constant and low dielectric loss of AMT crystal which are required properties to develop optoelectronic devices. The laser damage threshold value of AMT is 0.238 GW/cm 2 and photoconductivity study reveals the positive photoconductivity nature of the AMT crystal. The particle size dependent SHG studies were performed using Nd:YAG laser. The SHG efficiency of AMT is found to be 1.3 times greater than the standard KDP crystal. Third order nonlinear susceptibility χ (3) of AMT was assessed using an open aperture and closed aperture Z-scan technique and the value is 6.71×10 −6 esu. AMT crystal is found to exhibit good optical power limiting. The present work indicates that AMT is a potential material for optoelectronic and nonlinear optical devices.

Single crystals of 1 and 3 mol% Cr3+ doped l -alanine cadmium chloride monohydrate were grown by slow evaporation solution technique using double distilled water as solvent. The amount of chromium incorporated into crystal lattice was found using atomic absorption spectroscopy and was found that actual concentration incorporated into lattice was few ppm only. Lattice dimensions of grown crystals were analysed using powder X-ray diffraction technique and found that the crystals crystallised in monoclinic system with space group C2. Crystalline perfection of grown crystals were assessed using High Resolution X-ray diffraction and X-ray topographic technique and was found that incorporation of chromium has significantly improved the crystalline perfection. Thermal stability of doped crystals were studied using thermogravimetric analysis and found that thermal stability was improved with the incorporation of chromium. Further there optical properties were analysed using UV–vis spectroscopy.

High efficiency thermoelectric materials plays a vital role in power generation and refrigeration applications. Bismuth telluride (Bi2Te3) is one among them. In the present work single crystal of bismuth telluride was grown using vertical Bridgman technique. The phase of grown crystals was analysed using a powder X-ray diffractometer. Quality of the grown crystal was assessed by using high resolution X-ray diffractometer and observed that it is fairly good. Further mechanical investigations on grown crystal was carried out using nano-indentation technique and various mechanical properties like hardness, stiffness and Young’s modulus were evaluated. Observed results clearly indicate its suitability for thermoelectric applications.

Effects of the addition of semi-organic NLO materials potassium hydrogen malate monohydrate (PHMM) and sodium acid phthalate (NaAP) on the growth and various properties of ammonium dihydrogen phosphate (ADP) single crystal grown by the slow cooling method have been studied. The metastable zonewidth of pure and doped ADP were determined and compared. Nucleation studies show that metastable zonewidth and growth rate of ADP are enhanced by the dopants PHMM and NaAP. The grown crystals were subjected to Powder XRD, FT-IR, UV–vis, TG/DSC, microhardness and dielectric studies. The grown crystal has good optical transparency in the entire visible region, which is an essential requirement for a nonlinear crystal. Dielectric measurements reveal that doped ADP crystals have low dielectric loss and higher dielectric constant than pure ADP. The relative SHG efficiency measurements revealed that the dopant has enhanced the efficiency. Presence of dopant was confirmed by energy-dispersive spectrometry.

CZTSSe thin films are considered to be future of flexible thin film solar cell. Amount of S and Se in the CZTSSe thin films controls the band gap. Therefore, control over the concentration of S/Se is very important for enhancing the efficiency. CZTS thin films were deposited on SLG substrate by sequential reactive sputtering of metal targets. The films were annealed in Se atmosphere at 550 °C for 10–25 min in order to obtain CZTSSe thin films. Elemental, surface morphological, optical and structural properties of CZTSSe thin films have been investigated in detail. Optical band gap energy of CZTSSe thin films were in the range of 1.1–1.35 eV. XRD and Raman analysis were used to analyze the structure and phase purity of CZTSSe thin films. High intense peak at 27.9° in the XRD pattern corresponding to (112) plane was observed. High intensity of XRD peak corresponding to (112) direction revealed that the growth is oriented along (112) direction. Raman analysis also showed the presence of two peaks related to Se and S anions in CZTSSe thin films. In the Raman spectra of CZTSSe thin films; peaks corresponding to Se anions were observed at 190–206 cm−1 and peaks corresponding to S anions were observed at 329–338 cm−1. Elemental analysis results showed that S/Se ratio did not change much with increase in annealing time. To the best of our knowledge, this is the first report on the deposition of CZTSSe by sequential reactive sputtering of metal targets and controlled selenization.

Single crystals of LTA were grown by slow evaporation solution technique (SEST). Powder X-ray diffractometry (PXRD) confirmed the monoclinic crystal structure, whereas the high resolution X-ray diffractometry (HRXRD) ascertained the good crystalline perfection (FWHM=25 arcsec) of the as-grown single crystal. Optical study demonstrated the high optical transparency (85%). Photoluminescence (PL) spectroscopy illustrated the PL-emission at λ=388 nm and optical band gap ~3.2 eV. The SHG efficiency of LTA single crystal (6.61) is comparatively greater than the referenced (KDP) single crystal (6.08). Thermal analysis revealed that the crystal is thermally stable up to ~170 °C. The calculated value of the activation energy (ΔE) and corrected hardness (H0) for the crystal were found to be equal to 1.16 eV and 46.66 kg/mm2, respectively. The as-grown LTA single crystals can be used as a potential candidate for NLO material as well as in electronic and optoelectronic devices.

The present study attempts to explore and compare the seasonal variability in chemical composition and contributions of different sources of fine and coarse fractions of aerosols (PM2.5 and PM10) in Delhi, India from January 2013 to December 2016. The annual average concentrations of PM2.5 and PM10 were 131 ± 79 μg m−3 (range: 17–417 μg m−3) and 238 ± 106 μg m−3 (range: 34–537 μg m−3), respectively. PM2.5 and PM10 samples were chemically characterized to assess their chemical components [i.e. organic carbon (OC), elemental carbon (EC), water soluble inorganic ionic components (WSICs) and heavy and trace elements] and then used for estimation of enrichment factors (EFs) and applied positive matrix factorization (PMF5) model to evaluate their prominent sources on seasonal basis in Delhi. PMF identified eight major sources i.e. Secondary nitrate (SN), secondary sulphate (SS), vehicular emissions (VE), biomass burning (BB), soil dust (SD), fossil fuel combustion (FFC), sodium and magnesium salts (SMS) and industrial emissions (IE). Total carbon contributes ∼28% to the total PM2.5 concentration and 24% to the total PM10 concentration and followed the similar seasonality pattern. SN and SS followed opposite seasonal pattern, where SN was higher during colder seasons while SS was greater during warm seasons. The seasonal differences in VE contributions were not very striking as it prevails evidently most of year. Emissions from BB is one of the major sources in Delhi with larger contribution during winter and post monsoon seasons due to stable meteorological conditions and aggrandized biomass burning (agriculture residue burning in and around the regions; mainly Punjab and Haryana) and domestic heating during the season. Conditional Bivariate Probability Function (CBPF) plots revealed that the maximum concentrations of PM2.5 and PM10 were carried by north westerly winds (north-western Indo Gangetic Plains of India).

DFT computations supported by B3LYP/cc-pVTZ level theory have been employed to derive equilibrium geometry, vibrational wavenumbers and the hyperpolarizability values of the nonlinear optical (NLO) material L-Arginine Hydrobromide monohydrate (LAHBr). Changes in the atomic charge distribution among different groups due to the presence of strong electronegative atoms and the attenuation of O-H bonds of water molecule have been analyzed. H-bonding effects of LAHBr are examined with the aid of structural analysis, IR, Raman vibrations and NBO analysis. The occurrence of strong intra- and intermolecular N H⋯O, N H⋯Br and O H⋯O ionic hydrogen bonding and non-bonded interactions in making the LAHBr unit NLO active has been discussed. The charge transport mechanism is analyzed by using dielectric measurements and the obtained results suggest good quality of the crystal.

Long afterglow SrAl2O4:Eu2+,Dy3+ nanophosphors were synthesized via a facile but effectual auto-combustion technique followed by post-annealing treatment at elevated temperatures. The influence of various fuels during synthesis and thereafter improvement in the luminescence decay characteristics under various illuminant irradiations of long afterglow nanophosphors have been reported. Extensive studies on structural, morphological and luminescent properties of the as-synthesized afterglow nanophosphors have been presented. Powder X-ray diffraction studies confirm the presence of high-purity, single-phase monoclinic nanophosphors. HRTEM investigations confirm the formation of nanophosphors of particle size less than 50 nm. Photoluminescence emission is attributed to the characteristic d–f transition (4f65d1→4f7) of Eu2+ ions and was positioned at 512 nm. As-synthesized nanophosphors exhibit considerable confinement effects resulting into blue shift in emission maxima as compared to their bulk counterparts. The mechanism underlined for long afterglow has been discussed using trapping–detrapping model. The nanophosphor being multifunctional finds many interesting applications including dark-vision display, energy storage, fingerprint detection, in vivo and in vitro biological staining, etc.

Nonlinear optical single crystal of L-Proline trichloroacetate (L-PTCA) was successfully grown by Slow Evaporation Solution Technique (SEST). The grown crystals were subjected to single crystal X-ray diffraction analysis to confirm the structure. From the single crystal XRD data, solid state parameters were determined for the grown crystal. The crystalline perfection has been evaluated using high resolution X-ray diffractometer. The frequencies of various functional groups were identified from FTIR spectral analysis. The percentage of transmittance was obtained from UV Visible spectral analysis. TGA-DSC measurements indicate the thermal stability of the crystal. The dielectric constant, dielectric loss and ac conductivity were measured by the impedance analyzer. The DC conductivity was calculated by the cole-cole plot method.

Bare bulk tube superconducting current leads (CLs) of (Bi, Pb)2 Sr2 Ca2 Cu3 O10+x: 10 wt% Ag (Length = 410 mm, outer diameter = 45 mm, and inner diameter = 42 mm) have been found to show a degradation in the normal state affecting the superconducting properties due to ageing of the material. These reference samples (named as RF) have been studied over a period of five and ten years. A decomposition of the Bi-2223 phase has been observed after testing several times during the period affecting normal state and superconducting properties considerably. An attempt has been made in order to obtain reusable product using two recycling methods. In one of the methods, these degraded samples were re-sintered (named as RS) and in the second one, they were reprocessed (named as RP). Those is, in the second method, the steps of crushing, mixing, calcining, cold isostatically pressing into tubes, making silver current contacts at both end portions of this tube and finally of sintering were followed to make reprocessed bare bulk tube current leads. Both these RS and RP samples were sintered under identical conditions as those of the conditions used for the RF samples. Comparative analyses of the two recycling (RS and RP) methods with respect to normal state and superconducting state properties are also presented.

Vanillylideneaniline with chemical formula C 14 H 13 NO 2 (VAN), a second order nonlinear optical (SONLO) organic single crystal was synthesized and grown for the first time from dimethyl formamide (DMF) employing slow solvent evaporation technique. Single crystal X-ray diffraction data reveals that the crystal belongs to noncentrosymmetric orthorhombic space group C222 1 . The high-resolution diffraction curve containing single peak with full width at half maximum (FWHM) of 62 arc s ascertains VAN was perfectly crystallized and free from structural grain boundaries. The formation of the material was confirmed quantitatively by FTIR, 1 H 1 and 13 C NMR spectral analyses. The UV–vis–NIR spectrum reveals the percentage of the transmission of VAN crystal in the entire region. The variations of dielectric constant ( ɛ r ) and dielectric loss ( D ) with frequency at different temperatures were investigated. The SHG of VAN crystal is confirmed by Kurtz Powder technique. The mechanical strength of the crystal was estimated by Vickers hardness test. VAN has yield strength of 8.70 MPa. Thus the grown organic VAN single crystal can be recommended as a promising candidate for SONLO application and device fabrication technology.

A series of Bi1−xBaxFeO3 (x = 0.1, 0.2, 0.3, and 0.4) multiferroic samples have been prepared using rapid two stage solid state reaction method in order to study the effect of different concentrations of barium on the crystal structure, dielectric and magnetic properties. Structural analysis has been performed using X-ray diffraction (XRD) measurements. Rietveld refined XRD data confirms that all the samples except 40% are of single phase, having hexagonal structure with R3c space group. Unit cell volume increases with increase in Ba concentration. Dielectric measurements have been performed in the temperature range of 100–450 K at selected frequencies in the range 120–1120 kHz which show weak frequency dispersion. Activation energies are calculated and are almost same for all the samples. Exchange bias in hysteresis loops and considerable enhancement in magnetic properties have been observed for all the samples.

Single crystals of pure and l -Proline (LP) C 5 H 9 NO 2 doped ammonium dihydrogen phosphate (ADP) (NH 4 ) H 2 PO 4 were grown by slow evaporation solution technique (SEST) at ambient conditions. Powder X-ray diffraction (PXRD) analysis was carried out to confirm the crystal structure and no additional phase was observed due to doping except a systematic variation in peak intensities. FT-Raman analysis also confirms that there is no additional phase formation due to doping. Fourier transform infrared spectral analysis was done to examine the presence of various functional groups in the grown crystals. UV–VIS–NIR spectroscopic analysis was carried out to see the change in optical transparency of pure ADP and crystals due to LP with different doping concentrations. The high-resolution X-ray diffraction (HRXRD) analysis was carried out to examine the crystalline perfection and observed reasonable changes with LP doping. Second harmonic generation (SHG) efficiency measurement was done to examine the enhancement in the nonlinear optical characteristics of the grown crystals. The dielectric behavior of the samples shows that the dielectric constant decreased with increase the value of frequency. The effect of LP dopant on crystal morphology, mechanical properties of ADP has also been presented in this paper. The above studies reveal the effect of incorporation of LP into the lattice of ADP crystals.

Single crystals of pure and l -tartaric acid (LTA) C4H6O6 doped ammonium dihydrogen phosphate (ADP) (NH4) H2PO4 were grown by slow evaporation solution technique (SEST) at ambient conditions. Powder X-ray diffraction (PXRD) analysis was carried out to confirm the crystal structure and no additional phase was observed due to doping except a systematic variation in peak intensities. Fourier transform infrared spectral analysis was done to examine the presence of various functional groups in the grown crystals. UV–VIS–NIR spectroscopic analysis was carried out to see the change in optical transparency of pure ADP and crystals due to LTA with different doping concentrations. Second harmonic generation (SHG) efficiency measurement was done to examine the enhancement in the nonlinear optical characteristics of the grown crystals. The effect of LTA dopant on crystal morphology, thermal and mechanical properties of ADP have also been presented in this paper. The above studies reveal the effect of incorporation of LTA into the lattice of ADP crystals.

Gamma bis glycinium oxalate (GBGOx) crystal was synthesized and grown by slow evaporation solution technique. The structure of pure GBGOx crystal has been examined by single crystal X-ray diffraction analysis. The confirmation with single crystal XRD reveals that the crystal belongs to monoclinic system with space group C 2 . The FTIR spectrum was recorded to identify the expected functional groups. UV–vis-spectrum shows the lower cut off wavelength and 80% of transmittance in the UV–vis region. The photoluminescence measurement shows that the material is suitable for photonic devices. Preliminary measurement of green light emission using Kurtz powder technique indicates that their second harmonic generation (SHG) efficiency. The microhardness analysis revealed that the grown crystal belongs to soft material category. The encouraging results show that the GBGOx crystals have great potential applications in optical devices.

Bismuth Silicon Oxide (BSO) is an efficient material for piezo-electric and electro-optic applications. In this article, growth of BSO single crystal by high temperature Czochralski melt growth technique and its detailed mechanical characterization by Vickers microhardness, fracture toughness, crack propagation, brittleness index and yield strength have been reported. The raw material was synthesized by solid state reaction using the stoichiometric ratio of high purity bismuth tri-oxide and silicon di-oxide. The synthesized material was charged in the platinum crucible and then melted. The required rotation and pulling rate was optimized for BSO single crystal growth and good quality single crystal has been harvested after a time span of 5 days. Powder X-ray diffraction analysis confirms the parent crystallization phase of BSO. The experimentally studied mechanical behavior of the crystal is explained using various theoretical models. The anisotropic nature of the crystals is studied using Knoop indentation technique.

Single crystal of l -alanine cadmium chloride (LACC) has been grown by the conventional seed suspended technique. The grown crystals were subjected to various characterizations such as powder XRD, FTIR, UV–vis, second and third harmonic generation measurements. The structure of pure LACC crystal has been examined by powder X-ray diffraction analysis. The confirmation with single crystal XRD reveals that the crystal belongs to monoclinic system with space group C 2 . The FTIR spectrum was recorded to identify the expected functional groups and the molecular structure was confirmed by 1 H NMR spectrum. Dielectric measurements reveal that the grown crystals have very low dielectric loss. UV–vis-spectrum shows the lower cut off wavelength at 245 nm and transparency above 95% in the UV–vis region. The optical band gap was determined to be 5.12 eV. Preliminary measurement of green light emission using Kurtz powder technique indicates that their second harmonic generation (SHG) efficiency. The third order nonlinear optical parameters such as nonlinear refractive index ( n 2 ), nonlinear absorption coefficient ( β ) and third order susceptibility ( χ 3 ) are found to be in the order of 2.4233 × 10 −14 cm 2 /W, 0.2252 × 10 −4 cm/W, 0.9134 × 10 −15 esu, respectively by Z scan measurement. The encouraging results show that the LACC crystals have great potential applications in optical devices.

Sulfamic acid (SA) single crystals, both pure and doped with 1, 2.5 and 5 mol% Nd, were grown successfully in an aqueous solution by the slow cooling method. Powder X-ray diffraction patterns were recorded to check the variation in the lattice parameters and phase of the crystals. The optical transparency was found to be higProd. Type: FTPhest (∼80%) for the 1 mol% Nd3+ doped SA single crystal. The optical band gap was also calculated and found to be ∼4.31, 4.20 and 3.67 eV. The influence of Nd3+ doping on the crystalline perfection was assessed by a high resolution X-ray diffractometer (HRXRD) and shows that the grown crystals could accommodate Nd3+ at the interstitial positions in the crystalline matrix of SA up to some critical concentration without any deterioration in the crystalline perfection. The etching studies were carried out and the etch pits densities were calculated. The mechanical property of grown single crystals was also studied.

In the present work, we have grown single crystals of l -proline cadmium chloride monohydrate (LPCCM) by slow evaporation solution technique (SEST) at room temperature and recorded their live growth kinetics with the help of inverted microscope. Crystal size at various stages of growth and its corresponding morphology was also recorded. Powder X-ray diffraction (PXRD) analysis of LPCCM single crystals confirmed the orthorhombic structure. Respective values of crystallite size, strain and dislocation density have been calculated using PXRD data. Metal complex coordination of the single crystal is studied by FTIR spectroscopic. The optical properties of the grown crystals were investigated through UV–VIS spectroscopic studies and shows that the crystals have very low absorption in entire characterized wavelength range 200–800 nm. The optical band gap was calculated and found to be ∼5.6 eV. Optical constants of the material is determined by theoretical calculations. The chemical etching study was also carried out to study the density of defects in the grown crystals. The photoluminous excitation and emission spectra and thermal property by TGA/DTA curve were recorded. Further, the mechanical properties have been studied using Vicker's microhardness tester as well as many parameters such as fracture toughness (Kc), Brittleness index (Bi) and yield strength (σν) are presented. Dielectric studies have been carried out with varying frequency and temperatures.

Bulk single crystals of pure and xylenol orange (XO) admixtured l -arginine phosphate (LAP) were grown by slow cooling technique. The cell parameters and crystallinity of pure and dye admixtured LAP crystals were confirmed by single crystal and powder X-ray diffraction analyses. HRXRD analysis reveals the presence of xylenol orange dye in interstitial site of LAP crystal lattice and it confirms the crystalline perfection of grown crystals. The functional groups of grown crystals were confirmed by FTIR spectral analysis. UV–vis transmission studies show the characteristic absorption of xylenol orange admixtured LAP crystal. Vickers’ microhardness and laser damage threshold studies were carried out on these crystals. Kurtz and Perry powder test was conducted to measure the second harmonic generation efficiency of pure and dye admixtured LAP crystals.

A potentially useful semi organic nonlinear optical (NLO) material ⿿ glycine with barium nitrate and potassium nitrate (GBNPN) has been synthesized by slow evaporation technique. Good transparent GBNPN crystals were obtained in a time span of 3 weeks. The grown crystals were characterized by single crystal/powder XRD, UV⿿vis⿿IR absorption, FTIR, thermal analysis and powder SHG measurements have been studied. The grown crystals were thermally stable up to 137.53 °C. The GBNPN crystal exhibits second harmonic generation efficiency of about 1.35 times than that of potassium di hydrogen phosphate (KDP). Mechanical properties such as micro hardness (Hv) and Mayer's index, n, have been carried out by indentation method. The refractive index (μ) has been measured by the Brewster's angle method.

We report a high (∼94%) yield synthesis of intrinsic zinc oxide (ZnO) nanocrystal powders having crystallite sizes in the range 13–35 nm using a novel gel-incineration method with inexpensive precursor salts and citric acid as chelating agent. The influence of various precursor chemicals on the nanocrystallite size, morphology and luminescent properties has been studied in detail. It was identified that the ZnO nanocrystals prepared using organic precursor resulted the smallest crystallite size as compared to inorganic precursors. Reaction temperature was optimized to be ∼900 °C by simultaneous thermogravimetric analysis and differential scanning calorimetry studies. Morphology and microstructure of the ZnO nanocrystals have been studied using a scanning electron microscopy. Analysis of photoluminescence excitation and emission spectra enabled us to calculate the band gap energy and defect analysis of as prepared ZnO nanocrystals respectively. The stability of ZnO nanocrystals in water has been verified on time scale and its potential use has been successfully demonstrated for security marker applications.

Single crystal of pure and p-nitroaniline doped l -lysine monohydrochloride monohydrate were grown from the aqueous solution by slow evaporation solution growth technique at room temperature. In this paper, the effect of p-nitroaniline doping on the LLMHCL crystal properties have been studied elaborately. The grown crystals were characterized by powder X-ray diffraction, Fourier transform infrared (FTIR) spectroscopy, UV–vis-NIR, thermo gravimetric analysis (TGA) and hardness measurement. The lattice dimensions were calculated from the PXRD analysis and found that the title compound crystallizes in monoclinic crystal system. Presence of functional groups was identified from Fourier transform infrared spectroscopy (FTIR). UV–vis-NIR studies have been carried out in order to study the optical properties of the as grown and doped LLMHCL. Thermal stability has been assessed by thermo gravimetric analysis. Hardness measurements were done to calculate the mechanical strength of the material in order to check its suitability for device fabrications.

To reveal clearly the doping effect on the growth and properties of KDP single crystals, bulk concentration 1.0 mol% and 5 mol% of MnCl2 (Mn2+) was doped in KDP single crystals by using slow evaporation method. Interesting results like nucleation, rate of growth, and defect formations were found during the investigation. The different stages of live growth are recorded with the help of inverted microscope. Powder X-ray diffraction (XRD) analyses confirm the tetragonal structure of pure and doped KDP. The variation in the intensity of diffraction peaks shows the minute change in lattice parameters in correlation with morphology of varying Mn2+ doping concentrations. The above studies further reveal that the structure and morphology of the doped crystals are slightly distorted compared to the pure KDP crystal. The optical properties of the grown crystals have been investigated by using UV–visible spectra. The band gap energy for the doped KDP crystals was calculated from optical transmission spectrum.

Organic nonlinear optical crystal, 8-hydroxyquinolinium hydrogen maleate (8-HQM) with a dimension of 30×4×4 mm 3 was grown by the slow evaporation solution growth technique. The cell parameters of grown crystal were confirmed by single crystal X-ray diffraction analysis and it belongs to the noncentrosymmetric space group P2 1 2 1 2 1 . The crystalline perfection of 8-HQM crystal was examined by high resolution X-ray diffraction studies. UV–vis transmittance studies confirm the optical transparency window in the (480–900 nm) region. The TGA/DTA thermal measurements reveal that 8-HQM is thermally stable up to 160 °C. The laser damage threshold value of 8-HQM crystal was estimated to be 1.2 GW/cm 2 using a Nd:YAG laser. The relative second harmonic generation efficiency of 8-HQM crystal was found to be seven times greater than that of KDP.

ZnSe single crystal of size ∼25 mm lengths and ∼10 mm diameter was grown by vertical Bridgman technique using two zone tubular furnace from the synthesized polycrystal of the compound. The powder X-ray diffraction analysis confirmed the crystal system of the grown crystal. The optical band gap of the grown crystal was calculated and found to be ∼2.704 eV by UV–vis–NIR analysis. The crystalline perfection was assessed by using high-resolution X-ray diffractometer (HRXRD) and chemical etching studies which reveals that the grown crystal has good crystalline perfection. The etch pit dislocation density was calculated and found to be 2 × 10 6 cm −2 . Good crystalline perfection and less dislocation density of the grown crystals makes, it important for optoelectronic device fabrications. The dielectric studies were also done over a wide range of frequency 100 Hz to 10 MHz at room temperature.

The spectroscopic properties of the crystallized semiorganic nonlinear optical molecule Potassium Acid Phthalate (KAP) have been recorded and analyzed by FT-IR, Raman and UV techniques. The spectra were interpreted with the aid of normal coordinate analysis following structure optimizations and force field calculations based on density functional theory (DFT) at the B3LYP/6-311+G(d,p) level of theory. Normal coordinate calculations were performed using the DFT force field corrected by a recommended set of scaling factors yielding fairly good agreement between the observed and calculated wavenumbers. KAP is thermally stable up to 275.0 °C and optically transparent in the visible region.

The potential organic non-linear optical single crystal of L -lysine acetate has been grown by slow evaporation solution growth technique (SEST) at room temperature. It crystallizes in the monoclinic system with space group of P 2 1 . The crystalline perfection of the grown single crystal has been examined by high resolution X-ray diffraction analysis (HRXRD). The functional groups of the synthesized compound have been identified by 13 C NMR, 1 H NMR and FTIR analyses. The optical absorption studies show that the crystal is transparent in the entire visible region with a cut-off wavelength of 236 nm. The optical band gap is found to be 5.29 eV. The steady-state PL spectra was recorded for pure L -lysine acetate crystal at room temperature. The third harmonic generation efficiency of the crystal has been evaluated by Z-scan technique and its non-linear optical coefficient has been calculated. Birefringence measurement has been carried out in order to see the optical homogeneity of the grown specimen. Its electrical properties has been assessed by dielectric measurement at different temperatures. The calculated optical band gap is 5.29 eV. Its thermal parameters like thermal diffusivity ( α ), thermal effusivity ( e ), thermal conductivity ( k ) and heat capacity ( C p ) have been determined by photopyroelectric technique. Vickers micro hardness studies were carried out using a Vickers hardness tester equipped with a diamond square indenter. The piezoelectric measurement for L -lysine acetate has been also been carried at ambient condition.

Good quality single crystals of potassium dihydrogen orthophosphate (KDP) were grown with different doping concentration of Glycine by conventional solution technique in aqueous solution. X-ray diffraction study has been carried out in order to see the effect of dopant on the structural parameters of KDP. There is no additional phase was observed which was further confirmed by Raman spectroscopic analysis. The second harmonic generation efficiency was measured by using Kurtz powder technique. The relative second harmonic generation (SHG) efficiency of the grown crystals was found to be increased with doping concentration up to 2.5 mol%. Optical transmission study also revealed the same behaviour with enhancement up to 2.5 mol% concentration and later decreased but still higher than pure KDP. The mechanical strength was found to increase with increasing the doping concentration.

Pure and urea added zinc tris(thiourea)sulphate (ZTS) single crystals were grown by the solvent evaporation method from aqueous solutions. The grown crystals were characterized by X-ray powder diffraction, Fourier transform infrared, second harmonic generation and density measurements. The observed results show that the small amount of urea molecules were incorporated in the crystalline matrix of ZTS crystals. Dielectric measurements were carried out along a-, b- and c-directions of the grown crystals at various temperatures by the conventional parallel plate capacitor method with a fixed frequency of 1 kHz. The present study shows that the dielectric parameters (viz. dielectric constant, dielectric loss and a.c. conductivity) increases with the increase in temperature for all the grown crystals. Activation energies were also determined.

In the present work we focus on the coexistence of magnetic-electronic phases and hence phase separation in La 1 − x Ca x MnO 3 thin films in the composition range of 0.45 ≤ x ≤ 0.60. The oriented polycrystalline thin films were prepared by nebulized spray pyrolysis technique on single crystalline substrate LaAlO 3 [LAO (0 0 1)]. The lattice parameters are observed to decrease with increasing in Ca content and the structural/microstructural disorder is also seen to increase concomitantly. As the Ca content is increased from x = 0.45 to 0.55, the paramagnetic insulator (PMI) to ferromagnetic metal (FMM) transition temperatures ( T C / T IM ) are suppressed. This is accompanied by (i) appreciable suppression of the T C , (ii) sharp reduction in the magnetic moment, (iii) occurrence of a peak in the magnetization below T C , (iv) stronger bifurcation of the ZFC–FC magnetization, and (v) decline in the magnetization in the lower temperature regime. At x = 0.60, the FMM disappears and a weak FM insulator like phase is observed. In the vicinity of x = 0.55, the magnetic ground state resembles spin cluster glass. This is also confirmed by the occurrence of a hysteresis loop in the resistivity of the x = 0.55 measured during the cooling and warming cycle. The transition broadening up to x = 0.55 and the vanishing of the two transitions in x = 0.60 film along with the simultaneous decrease in the magnetic moment and enhanced resistivity show that the observed variations are due to the increase in the antiferromagnetic-charge ordered (AFM-CO) phase fraction at higher Ca content. This is also confirmed by the decrease in magnitude of the magnetoresistance and its temperature dependence. Our results demonstrate that, there is strong phase separation in the overdoped region (0.50 x ≤ 0.60) due to the presence of multiple magneto-electric phases.

Single crystals of acetoacetanilide have been successfully grown by slow evaporation solution growth method at room temperature. The grown crystal belongs to orthorhombic crystal system having the lattice dimensions of a = 8.686 A, b = 11.104 A, c = 19.232 A. Its crystalline perfection was examined by home-made high resolution X-ray diffractometer (HRXRD), and found that that the quality of the specimen is reasonable. The presence of carbon, hydrogen and nitrogen were experimentally determined by elemental analysis and that are in good agreement with the theoretically calculated values. Its laser damage threshold, phase matching and second harmonic generation efficiency were determined by using Nd:YAG laser as a source. Optical behavior of acetoacetanilide was examined by using photoluminescence studies. Its hyerpolarizability and HOMO–LUMO energies were calculated by using density functional theory (DFT).