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Pure, stable stoichimetric nano crystalline hydroxyapatite material was crystallized by double diffusion technique at physiological conditions, temperature at 37°C and pH at 7.4. The sample was sintered at 400°C, 750°C and 1200°C with equal interval of time. They were characterized by X-ray diffraction studies, Fourier Transformation Infra-Red analysis, Thermogravimetric analysis, Scanning Electron Microscopic studies and Atomic Force Microscopic studies. The X-ray analysis confirmed that the grown crystals are to be the pure form of hydroxyapatite. Infra-red studies confirmed CO free hydroxyapatite. Thermogravimetric studies showed the thermal stability of the hydroxyapatite crystals even at 1200°C. The presence of pores in the sintered sample was traced by scanning electron microscopy. Atomic force microscopy revealed the presence of nano crystalline HAP of size 0.958 nanometer in the samples grown using this technique. At higher temperature the deagglomeration of bulk phases and agglomeration of nano phases leads to the nano crystalline HAP were observed. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

Ammonia (NH 3 ) vapour is considered as a hazardous volatile, which has the potential to cause health concerns in humans. Exposure to NH 3 can lead to potentially fatal, severe burn injuries to human eyes, can cause encephalopathy, and also affects various physiological systems, including the liver, the kidneys and the immune system. Due to these prime factors, the advancement of chemi-resistive ammonia gas sensors at room temperature has drawn considerable attention among researchers. In this current work, tetragonal scheelite (T s )-BiVO 4 thin films were deposited by varying the substrate (growth) temperature via the chemical spray pyrolysis method. The deposited thin films were subjected to structural, optical, morphological and gas sensing assessment. The gas sensing results indicate that the BV250 film has an ultra-high sensor response ( I gas / I air = 58.2 for 25 ppm) even after 50 days at room temperature. Furthermore, it demonstrates excellent selectivity, rapid response time (190 ± 4 s)/recovery time (16 ± 5 s) and repeatability (up to 4 cycles), and performs well in relatively humid conditions. This study offers insights into T I gas / I air = 58.2 for 25 ppm) even after 50 days at room temperature. Furthermore, it demonstrates excellent selectivity, rapid response time (190 ± 4 s)/recovery time (16 ± 5 s) and repeatability (up to 4 cycles), and performs well in relatively humid conditions. This study offers insights into T s -BiVO 4 thin films as a sensing layer in a chemi-resistive gas sensor for ammonia detection at room temperature., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Trimethylamine (TMA) is highly toxic and can have lethal effects on living organisms. Detecting the presence of TMA in air is very important because, if the TMA level exceeds the OSHA (Occupational Safety and Health Administration) limit, it may harm the environment and endanger human life. Doping is an appropriate flexible way to change the electrical structures of metal oxide semiconductors (MOSs) and improve their ability to detect toxic gases. In this work, Mn-doped zinc ferrite thin film nanorods with agglomerated morphology were fabricated by a spray pyrolysis technique. For the first time, a comprehensive investigation was done on the gas sensing capabilities of Mn-doped ZnFe 2 O 4 thin films. The findings showed that ZFM1 had the best gas sensing characteristics, with high sensitivity ( S = 6.24), good selectivity, and quick recovery, towards 10 ppm TMA at ambient temperature. The alternate Mn-ZF sites are responsible for the rapid recovery because they can significantly increase the concentration of oxygen vacancies in the ZF crystal. 0.1 Mn doped ZnFe 2 O 4 (ZFM1) thin film exhibits greatly enhanced gas sensing properties towards TMA, because of its high surface-to-volume ratio and rough surface with a small nanorod structure. The sensor's response to 10 ppm TMA was measured 13 weeks later for stability testing. The stability test results show that the coated ZFM1 film works well as a TMA gas sensor. This work shows that ZF thin films are effective in detecting TMA in the atmosphere.

A novel third-order stilbazolium derivative single crystal, 4-[2-(4-dimethyl amino-phenyl)-vinyl]-1-methyl-pyridinium bromide (DMSB), was fruitfully harvested using methanol as a medium, through a slow evaporation technique. The solubility of the prepared DMSB powder was experimentally tested at different temperatures (30 °C to 50 °C) with a methanol solvent. Single crystal X-ray diffraction analysis (SCXRD) implied that the DMSB crystal crystallized in a centrosymmetric fashion (space group P 2 1 / c ) with the monoclinic crystal system. The molecular weight of the element present in DMSB was confirmed by CHN elemental analysis. Nuclear magnetic resonance (NMR) spectroscopic study confirmed the molecular structure of the DMSB crystal. All the functional group vibrations raised from the title compound were studied using Fourier transform infrared spectroscopy (FTIR). From the UV-visible spectrum, the absorbance nature and band gap of the grown DMSB crystal were determined. The photoluminescence study of the grown crystal exhibited an emission peak at 660 nm, which is attributed to the red light emission in the EM spectrum. The morphological characteristics of the crystal were characterized using atomic force microscopy (AFM). Hirshfeld surface analysis was employed to quantitatively explore the non-covalent interactions that are accountable for the crystal packing. The third-order nonlinear susceptibility was determined experimentally and it was found to be 1.6 × 10 -8 esu. These favourable Z-scan analysis results indicate that the DMSB crystal is a good candidate for different applications, such as photonics devices, optical computing, optical switches, and optical limiting., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (This journal is © The Royal Society of Chemistry.)

A novel ionic stilbazolium derivative single crystal of 4- N , N -dimethylamino-4- N -methyl stilbazolium 2-formyl benzene sulfonate (DSFS) was successfully cultivated with methanol as the solvent by using the slow evaporation technique. Structural confirmation was done using single-crystal X-ray diffraction (SCXRD), and the obtained results reveal that the DSFS crystal crystallized in a centrosymmetric pattern with P 1̄ space group. The presence of different vibrational modes in the DSFS crystal is affirmed via Fourier transform infrared (FTIR) spectroscopy. Linear optical constants such as cut-off wavelength, bandgap, extinction coefficient, Urbach energy, electrical conductivity and optical conductivity of the titular crystal were found from ultraviolet-visible-near infra-red spectroscopy (UV-Vis-NIR). The emission wavelength of the title crystal lies in the red region (620 nm), which was confirmed from the photoluminescence spectroscopy (PL). The surface nature of the grown ionic crystal was examined through the etching and atomic force microscopy (AFM) technique. With a He-Ne laser as the source, Z scan analysis was carried out to study the third-order nonlinear properties of the DSFS crystal., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

This paper focuses on the evaluation of mechanical and biological properties of laser shock peening (LSP) orthopaedic grade Ti-6Al-7Nb alloy. LSP surface treatment was conducted at laser energy of 3 to 7 J with overlaps of 33%-67%, and with a 3 mm laser spot size. Cell viability on laser shock peened surface was evaluated through in-vitro MTT assay, using osteoblast-like MG63 cells for the first-time. Residual stresses, microhardness, microstructure, sliding wear and wetting properties were investigated. Compressive residual stresses were found at various depths due to controlling the LSP parameters, compared to the as-received surface. The laser shock peened surfaces were hardened from 365HV 0.05 to 405HV 0.05 , while the as-received surface was 320HV 0.05 . The average sub-grain size was refined from 14% to 36% after LSP. The wear resistance was also controllable by altering LSP parameters. The MTT results show that the cell viability on the laser shock peened surfaces was comparatively lower than that of the untreated surface after 24 h. However, after 72 h, the cell viability on modified surfaces were significantly improved. This work indicated that laser shock peened surfaces have a strong potential to decrease the pain from orthopaedic implant failures and promote the cytocompatibility between the bone and implant.

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)., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Somatostatin (SOM) cortical levels decline in Alzheimer's disease (AD) in correlation with cognitive impairment severity, the latter being closely related to the presence of neurofibrillary tangles. Impaired olfaction is another hallmark of AD tightly related to tau pathology in the olfactory pathways. Recent studies showed that SOM modulates olfactory processing, suggesting that alterations in SOM levels participate to olfactory deficits in AD. Herein, we first observed that human olfactory peduncle and cortex are enriched in SOM cells and fibers, in aged postmortem brains. Then, the possible link between SOM alterations and olfactory deficits was evaluated by exploring the impact of age and tau hyperphosphorylation on olfactory SOM networks and behavioral performances in THY-Tau22 mice, a tauopathy transgenic model. Distinct molecular repertoires of SOM peptide and receptors were associated to sensory or cortical olfactory processing structures. Aging mainly affected SOM neurotransmission in piriform and entorhinal cortex in wild-type mice, although olfactory performances decreased. However, no further olfactory impairment was evidenced in THY-Tau22 mice until 12 months although tau pathology early affected olfactory cortical structures. Thus, tau hyperphosphorylation per se has a limited impact on olfactory performances in THY-Tau22 mice., (Copyright © 2015 Elsevier Inc. All rights reserved.)

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)., (Copyright © 2014. Published by Elsevier B.V.)

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.

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., (Copyright © 2014 Elsevier B.V. All rights reserved.)

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 P21/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 1100nm shows the cut-off wavelength occurs at 371nm. 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., (Copyright © 2013 Elsevier B.V. All rights reserved.)

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., (Copyright © 2013 Elsevier B.V. All rights reserved.)

In the title salt, C16H18NO(+)·C10H7O3S(-), the substituents attached to the central C=C bond adopt a trans conformation and the benzene and pyridinium rings are nearly coplanar, making a dihedral angle of 6.01 (9)°. The crystal structure features weak C-H⋯O hydrogen bonds and C-H⋯π inter-actions .

A novel organic nonlinear optical material 4-fluoro 4-nitrostilbene (FONS), with molecular formula (C(14)H(10)FNO(2)) 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 "P2(1)". 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 (1)HNMR. 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 (E(g)) 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)., (Copyright © 2013 Elsevier B.V. All rights reserved.)

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=7.65Å, b=7.85Å and c=11.07Å. 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)., (Copyright © 2012 Elsevier B.V. All rights reserved.)

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., (Copyright © 2012 Elsevier B.V. All rights reserved.)

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., (Copyright © 2011 Elsevier B.V. All rights reserved.)

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.

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 HPO(4) species in the phosphoric system. The pH range in which HPO(4)(2-) 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.