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We herein record the synthesis as well as the results of our investigations on the structure as well as properties - thermal, mechanical, surface and nonlinear optical (NLO) - of semiorganic bisglycine lithium perchlorate (BGLP) single crystals. BGLP single crystal with dimensions 14× 3 × 2 mm3 has been synthesized and its structure and lattice parameters have been identified with the aid of X-ray diffraction. The vibrational spectrum of BGLP has been investigated making use of FT-IR and FT-Raman spectra. Dielectric constant of BGLP is found to show variations with frequency as well as temperature, which remains constant at high frequencies, the causes of which have been discussed. BGLP is manifested to be thermally stable up to 256ºC as revealed from thermogravimetric analyses. The two-dimensional nucleation mechanism in the growth of BGLP crystals have been understood from chemical etching studies. The potential applications of BGLP in optical switching is evident from its third order NLO response seen in the Z-scan curves.

This article experimentally and statistically reports the convective heat transfer performance of a cylindrical mesh-type heat pipe apparatus filled with ZrO2-CeO2/water-ethylene glycol nanofluids. In this regard, ZrO2-CeO2 nanoparticles were synthesized and characterized through the Scanning Electron Microscope and Powder X-ray diffraction methods followed by the preparation of hybrid ZrO2-CeO2 nanofluids of various concentrations ranging from 0.025 to 0.1%. The heat transfer features of a tubular heat pipe with a mixture of the ZrO2-CeO2 nanofluid were evaluated. A 5.33% decrease in thermal resistance value and a 41.16% increase in heat transfer ability with increased power input were observed. The potent regression models were proposed to estimate heat transfer features of the heat pipe. The ANOVA statistical method has been employed to determine the P value and the F value of the models towards enhancing the reliability and accuracy of the developed models. The outcome revealed that the proposed models are reliable and have the best fit with the experimental data for 30–60 W power. The correlations’ results were validated against the experimental data and showed high accuracy. Moreover, the accuracy of the developed models was ensured through R -squared and adjusted R -squared values.

This paper deals the synthesis and characterization of Pure Hydroxyapatite (Pure HAp) nanopowderan its nanocomposites. Hydroxyapatite - Zinc (HAp-Zn), Hydroxyapatite - Manganese (HAp-Mn) Hydroxyapatite - Titanium (HAp-Ti) and Hydroxyapatite - reduced Graphene oxide (HAp-rGO). The impact of Zn, Mn, Ti and rGO on the underlying, morphological, antimicrobial property and biocompatibility of hydroxyapatite nanopowders are contemplated. The structural characterization analysed through XRD. Pure HAp, HAp-Ti and HAp-rGO displayed hexagonal structure and fuse of Zn and Mn in the host lattice changed the construction into orthorhombic and rhombohedral. The normal crystallite size goes from 51 nm to 37 nm for different nanocomposites. The consolidation of cations (Zn2+ Mn2+ and Ti4+) and anion (CO3 2- ) diminished the crystallite size. Blended nanocomposites has hexagonal construction though there is hexagonal to orthorhombic progress in HAp-Zn and hexagonal to rhombohedral change in HAp-Mn nanocomposites The presence of functional groups in the samples is investigated utilizing FTIR examination. Surface morphology and compound organizations are examined utilizing Scanning Electron Microscope (SEM) and Energy Dispersive X-beam investigation (EDX) individually. The in-vitro antibacterial exercises and biocompatibility of the combined hydroxyapatite and its nanocomposite are examined utilizing Kirby-Bauer antibacterial testing and MTT assay individually. The outcomes show that Titanium and reduced Graphene Oxide fused hydroxyaptite nanocomposites are more harmful against every bacterial strain and didn't show any harmfulness against living tissues.

In this present work, nanosize zinc oxide particles were prepared via modest coprecipitation synthesis route. Powder X-ray diffraction pattern was applied for calculating the size of crystallites in the prepared sample. Fourier Transform Infra-Red spectrum established the Zn-O bands at 539 and 433 cm−1 in nano ZnO sample. The structural analysis was done using Scanning Electron Microscopy (SEM) studies for ZnO nanoparticles. Ultrasonicated two step procedure was followed to disperse the produced nanoparticles in the combination of water (60%) and ethylene glycol (40%) to produce ZnO nanofluids with five different particle volume fractions from 0.0125% to 0.1%. To overcome the stability problem and uniform distribution of nanoparticles within the fluid, Cetyl Trimethyl Ammonium Bromide (CTAB) dispersant was added within the suspension while preparation. The investigation results of viscosity, density as well as thermal conductivity at various temperatures showed the enhanced results than the base fluid combination. Huge improvements in thermophysical properties leads the ZnO nanofluid as an alternate working liquid in heat transferring systems.

The development of bone-implant materials with enhanced bioactivity and biocompatibility has become important in the field of orthopedics. This preparation of nanocomposites of pure Hydroxyapatite (HAp) nanopowder, Hydroxyapatite-Zinc (HAp-Zn), Hydroxyapatite-reduced Graphene oxide (HAp-rGO) and Hydroxyapatite-Zinc-reduced Graphene Oxide (Hap-Zn-rGO) were accomplished using the sol–gel method. The effect of Zn and rGO on the structural, morphological, optical, antimicrobial property and biocompatibility of hydroxyapatite nanopowders are studied. The structural characterization analysed through XRD. The pure HAp and HAp-rGO exhibited hexagonal structure and incorporation of Zn in the host lattice changed this structure into orthorhombic. The average crystallite size ranges from 37 to 51 nm for various nanocomposites. The incorporation of rGO and Zn ions decreased the overall crystallite size. The presence of functional groups in the samples is analyzed and confirmed using FTIR analysis. The SEM photos revealed the structures and morphology of the nanoparticles. The chemical compositions are investigated using Energy Dispersive X-ray analysis (EDX), and all the ratios are in good agreement with the stoichiometry ratio. The photoluminescence emission peaks received around 468 nm and 385 nm and the reasons are discussed in terms of oxygen vacancies and some electronic transition between states. The optical band gap values were redshifted due to the incorporation of rGO with HAp. The in vitro antibacterial activities and biocompatibility of the synthesized pure hydroxyapatite and HAp-Zn-rGO nanocomposite are investigated using Kirby-Bauer antibacterial testing and MTT assay, respectively. The results show that zinc incorporated hydroxyapatite nanocomposites are more toxic against all bacterial strains and did not show any toxicity against living tissues.

Hybrid nanofluids are attracted by the researchers due to their remarkable thermal conductivity as well as heat transfer behavior. Zinc oxide (ZnO) and magnesium oxide (MgO) nanoparticles were synthesized by co-precipitation and sol–gel method. The nanoparticles were characterized through X-ray diffraction studies, Fourier Transform Infra-Red spectroscopy analysis and scanning electron microscopy and energy dispersive X-ray spectroscopy methods. The produced nanoparticles were converted into nanofluids by adding a base solution as a blend of ethylene glycol and water (60:40%) and surfactant as cetyl trimethyl ammonium bromide (CTAB) using ultra-sonication process in the two-step method. Hybrid nanofluids of different concentrations (0%, 0.0125%, 0.025%, 0.05%, 0.075% and 0.1%) have been prepared and the effect of thermal conductivity, density and viscosity were determined at various temperatures(30–80 °C).The performance of heat pipe was analyzed with hybrid ZnO-MgO nanofluids by convective heat transfer method for three heat power inputs (30–90 W). ZnO-MgO hybrid nanofluid exhibit enhanced thermophysical properties as compared to base fluid alone. Decrease in thermal resistance and improvement in the heat transfer coefficient of nanofluids was observed by 4.07% and 28.9% respectively. The enriched thermphysical and heat transfer properties of this hybrid nanofluid could be used for heat transfer applications in heat exchanging devices.

Solar photocatalytic technology based on semiconducting materials has gained the attention of the scientific community to solve the energy crisis and environmental remediation. Zeolitic imidazolate frameworks (ZIFs) are a subfamily of metal–organic frameworks (MOFs) with the isomorphic topologies of zeolites and coordinative compositions of MOFs. Owing to high specific surface areas, tunable channels and high thermal stabilities, zeolitic imidazolate frameworks (ZIFs) have been used in catalytic applications. In this paper, ZIF-8 was used as a matrix to synthesize 0D/2D heterojunction photocatalysts, viz., ZnO/C3N4-x% (x = 2.5, 5 and 10), for the photocatalytic degradation study of rhodamine B (RhB). The synthesized composite materials were characterized using FTIR, PXRD, UVDRS, PL, TEM, and BET analyses. TEM images showed the nearby contacts between ZnO and C3N4 in the hybrid and the uniform distribution of ZnO on the surface of the C3N4 nanosheet, thus increasing the development of 0D/2D heterojunction. The hybrid system ZnO/C3N4-5% (ZCN-5) showed good photocatalytic activity for the degradation of RhB under sunlight. A possible mechanism for the improved photocatalytic activity of the ZnO/C3N4 composite is also suggested. This exploratory study demonstrates the effective separation and migration of photo-induced electron–hole pairs between the 2D C3N4 sheet and 0D ZnO for the improved performance of heterojunction photocatalysts.

In this study, nanostructured titanium (Ti) thin films were prepared by direct current magnetron sputtering (diode mode) and supported discharge (triode mode) on a stainless steel substrate. The X-ray diffraction pattern shows a preferred orientation (002) plane and exhibits a hexagonal cubic structure for the film prepared at a lower working pressure (0.7 Pa). The electrical resistivity was found to be 15 µΩ-cm. The scanning electron microscopy analysis indicates that the coatings in triode mode have agglomerates with larger grains compared to the DC magnetron sputtering diode mode. The surface topography was examined by atomic force microscopy. The electrochemical studies of the Ti thin films coated at a lower working pressure (0.7 Pa) provide evidence for better corrosion resistance.

In the title salt, {[Li(C2H5NO2)2]ClO4} n , the Li+ cation is coordinated by four carboxylate oxygen atoms of the glycine molecules with a distorted tetrahedral geometry. The glycine exists in a zwitterionic form with protonated amino and deprotonated carboxylate groups. In the crystalline state, the title salt is primarily stabilized by intermolecular N—H...O and Cα—H...O interactions which interconnect various units. Hirshfeld surface analysis indicates that the intermolecular H...O/O...H interactions are the most important contributors to the crystal packing.

Semiorganic material of bis-glycine cobalt sulphate pentahydrate (BGCS) was synthesized and single crystals of BGCS were grown by slow evaporation technique at room temperature. Three dimensional crystal structure of BGCS crystal elucidated by single crystal X-ray diffraction analysis reveals that the crystal belongs to triclinic system with centrosymmetric P-1 space group. Fourier transform infrared (FT-IR) spectral analysis was carried out and the presence of various functional groups of BGCS were identified. UV–Vis–NIR spectral analysis of BGCS crystal shows that the crystal is transparent between the wavelengths 200 and 1100 nm. Vickers microhardness study of the BGCS was carried out. Dielectric constant and dielectric loss of BGCS crystal were measured in the frequency range of 50 Hz–2 MHz at room temperature. Thermogravimetric, differential thermal analysis and differential scanning calorimetric studies carried out for the BGCS single crystal revealed that the grown crystal is stable up to 214 °C. Thermodynamic parameter showed that the decomposition reaction of BGCS is non-spontaneous. Etching study was carried out on the surface of the crystal using double distilled water as etchant. Increase in the etching time from 10 to 15 s developed staircase shaped etch pattern. The thermal parameter of BGCS was calculated from photoacoustic spectroscopy. Antibacterial activity was carried out in-vitro against gram negative i.e. Escherichia coli, Pseudomonas aeruginosa, Salmonella typhi; gram positive bacteria Staphylococcus aureus.

Well-developed transparent single crystals of bis-glycine lithium bromide were grown by the slow evaporation method. The grown crystals were characterized by powder X-ray diffraction analysis, Fourier transform infrared spectroscopy, thermogravimetric analysis (TGA), differential thermal analysis and differential scanning calorimetry analyses. UV–VIS–NIR spectrum shows excellent transmission in the UV, visible and NIR regions. Mechanical properties of the grown crystals were studied using the Vickers microhardness tester. Third-order nonlinear optical properties were studied in detail by the Z-scan technique with He–Ne laser radiation of wavelength 632.8 nm and the corresponding nonlinear refractive index, absorption coefficient and optical susceptibility were calculated.

In the present investigation, lithium cobalt oxide (LiCoO2) thin films were synthesised by the sol–gel process coupled with a cost-effective spin coating method using citric acid as a chelating age...

LiMn2O4thin films prepared by cost-effective spin coating method using optimized coating conditions are reported. Spin rate was varied and spin rate dependent properties were studied. Prepared films were characterized for their structural, morphological and optical properties. X-ray diffraction study of LiMn2O4thin films confirmed the cubic spinel structure with the preferred orientation along (1 1 1) plane. Optical absorption studies showed band gap energy of 3.02 eV for the grown LiMn2O4films. FT-IR bands assigned to asymmetric stretching modes of MnO6group were located around 623 cm-1and 514 cm-1for the LiMn2O4thin films. The weak band observed at 437 cm-1was attributed to the LiO4tetrahedra. The films showed high conductivity value 0.79 S/cm indicating the generation of effective network of the film for enhanced charge transport. AFM micrographs of the LiMn2O4films deposited at 3000 rpm and 3500 rpm showed uniform distribution of fine grains throughout the surface without any dark pits, pinholes and cracks.

Single crystal of a novel metal organic nonlinear optical (NLO) cadmium (II) dibromide l - proline monohydrate (CBLPM) of size 7 × 7 × 5 mm 3 was grown from slow evaporation technique. Single crystal X – ray diffraction analysis reveals that the crystal belongs to orthorhombic system with lattice parameters a = 10.1891 (8) A, b = 13.4961 (11) A, c = 7.4491 (5) A and space group P 2 1 2 1 2 1 . The powder X – ray diffraction pattern of CBLPM was recorded and the X – ray diffraction peaks were indexed. The various functional groups of CBLPM were identified by the FT – IR and FT – Raman spectral analyses. The optical transmittance window and lower cut off wavelength of CBLPM were identified from UV – Vis – NIR studies. The mechanical strength of the grown crystal was estimated using Vickers microhardness test. Dielectric constant and dielectric loss measurements were carried out at different temperatures in the frequency range of 50 Hz - 2 MHz. The photoluminescence spectrum was recorded in the wavelength range 200–400 nm and the estimated optical band gap was ∼4.1 eV. Etching studies were carried out for different etching time. Thermal stability of CBLPM was determined using thermogravimetric analysis. Laser induced damage threshold study was carried out for the grown crystal using Nd:YAG laser. Size dependent second harmonic generation efficiency of the grown crystal was determined by Kurtz and Perry powder technique with different particle size using Nd:YAG laser with wavelength 1064 nm. Second harmonic generation efficiency of the powdered CBLPM crystal was ∼2.3 times that of potassium dihydrogen orthophosphate.

Single crystal of α-nickel sulphate hexahydrate, α-NiSO4. 6H2O (α-NSH) is grown from aqueous solution by slow evaporation method. Solubility and metastable zone width of α-NSH are determined from the aqueous solution. The three dimensional structure is elucidated by single crystal X-ray diffraction studies. The α-NSH crystallizes in the non – centrosymmetric tetragonal space group P41212. The relative contributions of various intermolecular interactions involved in the crystal structure are quantified using Hirshfeld surface analysis and the decomposed two dimensional fingerprint plots. Fourier transform infrared spectral analysis and Vickers microhardness studies are carried out to characterize the grown crystal. Further the grown crystals are characterized using TGA, DSC, UV–Vis–NIR and dielectric analysis. The third order nonlinear optical properties are studied by Z–scan technique with He Ne laser radiation of wavelength 632.8 nm and the corresponding nonlinear refractive index, absorption coefficient and optical susceptibility are calculated. Crystalline perfection is assessed by etching studies and laser damage threshold is observed for the grown crystal.

The crystal structure of new monoclininc polymorph of l-dopa HCl is reported, and hydrogen-bonding inter­actions are discussed., The title mol­ecular salt, C9H12NO4 +·Cl−·C9H11NO4, is isotypic with that of the bromide counterpart [Kathiravan et al. (2016 ▸). Acta Cryst. E72, 1544–1548]. The title salt is a second monoclinic polymorph of the l-dopa HCl structure reported earlier in the monoclinic space group P21 [Jandacek & Earle (1971 ▸). Acta Cryst. B27, 841–845; Mostad & Rømming (1974 ▸). Acta Chemica Scand. B28, 1161–1168]. In the title compound, monoclinic space group I2, one of the dopa mol­ecules has a positive charge with a protonated α-amino group and the α-carb­oxy­lic acid group uncharged, while the second dopa mol­ecule has a neutral charge, the α-amino group is protonated and the α-carb­oxy­lic acid is deprotonated. In the previously reported form, a single dopa mol­ecule is observed in which the α-amino group is protonated and the α-carb­oxy­lic acid group is uncharged. The invariant and variations of various types of inter­molecular inter­actions present in these two forms of dopa HCl structures are discussed with the aid of two-dimensional fingerprint plots.

A novel nonlinear optical single crystal of cytosinium hydrogen selenite was grown from aqueous solution of cytosinium hydrogen selenite by slow solvent evaporation method at room temperature. The structural properties of grown crystal have been studied by single crystal and powder X-ray diffraction analysis. Presence of various functional groups was identified from Fourier transform infrared spectroscopy. The optical transmittance and absorbance spectra were recorded by UV–vis-NIR spectrometer and the grown crystal possesses good transparency in the entire visible region. The dielectric constant and dielectric loss of the crystal were calculated as a function of frequency at different temperatures. The mechanical strength of the cytosinium hydrogen selenite crystal was estimated using Vicker’s microhardness tester. Etch patterns of the cytosinium hydrogen selenite crystal were obtained using distilled water as etchant for different etching time. Second harmonic generation efficiency tested using Nd:YAG laser is about 1.5 times that of KDP.

Semiorganic single crystals of bis-glycine manganese chloride (BGMC) of dimension 5 × 3 × 3 mm 3 were grown from aqueous solution by slow evaporation method at room temperature. The crystal structure and lattice parameters were determined for the grown crystal by the single crystal X-ray diffraction studies. BGMC was subjected to FT-IR and FT-Raman spectral analyses. The lower cutoff wavelength observed from UV–vis–NIR transmittance spectrum is 271 nm. The mechanical strength of the grown crystal was estimated using Vickers microhardness tester. The dielectric response of the grown crystal was analyzed at different temperatures in the frequency range from 50 Hz to 2 MHz. Thermal properties were investigated by thermogravimetric, differential thermal and differential scanning calorimetric analyses. Chemical etching study shows the distribution of etch figures of various shapes in the grown single crystal. The third order nonlinear optical properties of BGMC were investigated by Z-scan technique employing He–Ne laser radiation of wavelength at 632.8 nm.

Single crystals of two of the l -amino acids (lysine and alanine) complexed with L-mandelic acids are prepared by slow evaporation technique and X-ray diffraction analysis has been carried out. Single crystal X-ray analysis reveals that lysine-mandelic acid crystallized as a dihydrate form. In the crystalline state, the lysine molecule exists in the cationic form in which the backbone and side chain amino groups are protonated and the carboxylic acid is deprotonated. The carboxylic acid proton of the mandelic acid is transferred to the lysine side chain and thus carries a negatively charged ion. The lattice water molecules are located near the amino groups of the lysine. In contrast, alanine molecule exists in the zwitterionic form in which amino group is protonated and carboxylic acid is deprotonated and the mandelic acid is in the neutral form in the re-determined alanine-mandelic acid complex. Crystal packing of lysine-mandelate and alanine-mandelic acid complexes is qualitatively analyzed using Hirshfeld surfaces and 2D-fingerprint plots. The energetics of different dimeric pairs observed in complexes is quantitatively analyzed using PIXEL energy analysis. Topological parameters derived from QTAIM framework are used to delineate the nature of different intermolecular interactions formed in lysine/alanine-mandelic acid complexes. In this work, we used IQA scheme to evaluate the strength of charged assisted hydrogen bonds in the title complexes.

Metal-semi organic NLO single crystal of Cadmium (II) dibromide l - Proline monohydrate (CBLPM) has been synthesized and the crystal was grown from solution by room temperature slow evaporation method. The crystal structure and cell parameters were refined by Rietveld refinement technique and confirmed that the metal-semi organic samples are in the orthorhombic system with space group P212121. The crystal structure of CBLPM is stabilized by intermolecular N–H…O, N–H….Br, O–H….O and O–H….Br hydrogen bonds. The water molecules serve as donors for the weak O–H⋯O and O–H⋯Br hydrogen bonds which link adjacent chains forming a three-dimensional structure. A Hirshfeld surface analysis suggests that the most significant contribution to the crystal packing is by H⋯Br contacts (26.2%). The complete vibrational features and electronic absorption spectra of the title compound were analyzed by FT-IR, FT-Raman and UV–visible spectra combined with density functional theory and time-dependent density functional computations. The second-order hyperpolarizability value of the molecule was also calculated at density functional theory method. The third-order nonlinear optical properties of the crystal were studied by Z-scan techniques using CW laser with wavelength 532 nm. The open aperture result exhibits the saturation absorption, which indicates that this material has potential candidate for optical limiting applications.

The seasonal abundance and spatial distribution of ichthyoplankton in relation to environmental parameters were made from October 2011 to September 2012 in the estuarine and coastal waters of Coleroon. A total of 25,810 finfish eggs were collected in the Coleroon estuary belonging to 7 orders which include 24 families and 46 taxa. Majority of the eggs represents the order of Perciformes (13 family) followed by Culpeiformes (5 family), Mugiliformes, Anguliformes, Tetradontiformes, Atheriniformes, and Gonorhynchiformes (1 family form each order). In addition, a total of 11,320 finfish larvae also were collected belonging to 7 orders which include 24 families and 45 taxa, the majority of the group belongs to the order of Perciformes (15 family) followed by Culpeiformes (4 family), Mugiliformes, Anguliformes, Tetradontiformes, Atheriniformes, and Gonorhynchiformes (1 family form each order). In the present observation, both eggs and larvae of finfish were higher during postmonsoon whereas lesser number of eggs was recorded in summer and larvae in premonsoon season. The physico-chemical parameters viz., Surface water temperature, salinity, pH, dissolved oxygen, Biological oxygen demand and NH 3 are also provided a relatively stable environment which was favorable for larval production and survival in the Coleroon estuarine region.

In the title polymer, zwitterionic proline and water mol­ecules inter­act with the bromide counter-anions through inter­molecular N—H⋯Br and O—H⋯Br hydrogen-bonding inter­actions, providing a novel supra­molecular structure., In the title coordination polymer, {[Sr(C5H9NO2)(H2O)4]Br2}n, the proline mol­ecule exists in a zwitterionic form with one of the ring C atoms disordered over two sites [site-occupancy factors = 0.57 (6):0.43 (6)]. The SrII ion is nine-coordinated by six water O atoms, two monodentate and two μ2-bridging, and three carboxyl­ate O atoms of the proline ligands, with two bridging [Sr—O range = 2.524 (4)–2.800 (5) Å]. In the crystal, there is no direct inter­action between the proline mol­ecules. However, the proline and water mol­ecules associate with the bromide counter-anions through a number of inter­molecular O—H⋯Br and N—H⋯Br hydrogen-bonding inter­actions, giving a three-dimensional supra­molecular structure.

The characteristic structural feature of the title compound is the formation of cationic chains extending parallel to [001], with the Br− counter-anions located in between. Inter­molecular N—H⋯O, N—H⋯Br, O—H⋯O and O—H⋯Br hydrogen bonds stabilize the structure., In the title coordination polymer, {[Sr(C2H5NO2)2(H2O)3]Br2}n, the Sr2+ ion and one of the water mol­ecules are located on twofold rotation axes. The alkaline earth ion is nine-coordinated by three water O atoms and six O atoms of the carboxyl­ate groups of four glycine ligands, two in a chelating mode and two in a monodentate mode. The glycine mol­ecule exists in a zwitterionic form and bridges the cations into chains parallel to [001]. The Br− counter-anions are located between the chains. Inter­molecular hydrogen bonds are formed between the amino and carboxyl­ate groups of neighbouring glycine ligands, generating a head-to-tail sequence. Adjacent head-to-tail sequences are further inter­connected by inter­molecular N—H⋯Br hydrogen-bonding inter­actions into sheets parallel to (100). O—H⋯Br and O—H⋯O hydrogen bonds involving the coordinating water mol­ecules are also present, consolidating the three-dimensional hydrogen-bonding network.

Leptospirosis is a disease caused by spp. Leptospira, also known as Weil’s disease if it manifests with jaundice. It can be associated with respiratory, renal, hepatic and haematological complications and most importantly carries a high mortality when untreated. We describe a case of a 53 year old man presenting with myalgia and fever in whom the diagnosis of leptospirosis was not initially considered. Following a deterioration in his condition a careful history revealed an apparent brief exposure to animal urine and subsequent grossly positive Leptospira serology. Treatment of his condition led to complete resolution after a brief stay on the intensive care unit. This case highlights the atypical nature of a presentation of Leptospirosis, its respiratory complications, and importance of serological testing in its diagnosis.

Silver nanoparticles (Ag NPs) of different sizes have been prepared by chemical reduction method and characterized using UV–vis spectroscopy and transmission electron microscopy (HRTEM). Fluorescence spectral analysis showed that the quenching of fluorescence of textile dyeing waste water (TDW) has been found to decrease with decrease in the size of the Ag NPs. Experimental results show that the silver nanoparticles can quench the fluorescence emission of adsorbed TDW effectively. The fluorescence interaction between Ag NPs (acceptor) and TDW (donor) confirms the Forster Resonance Energy Transfer (FRET) mechanism. Long range dipole–dipole interaction between the excited donor and ground state acceptor molecules is the dominant mechanism responsible for the energy transfer. Furthermore, photocatalytic degradation of TDW was measured spectrophotometrically by using silver as nanocatalyst under UV light illumination. The kinetic study revealed that synthesized Ag NPs was found to be effective in degrading TDW.

In the title salt, crystalline water mol­ecules serve as donors for the weak inter­molecular O—H⋯O and O—H⋯Br hydrogen bonds which link adjacent polymeric chains., In the title coordination polymer, {[CdBr2(C5H9NO2)]·H2O}n, the CdII ion is coordinated by four bromido ligands and two carboxyl­ate oxygen atoms of two symmetry-related proline ligands, which exist in a zwitterionic form, in a distorted octa­hedral geometry. There is an intra­molecular N—H⋯O hydrogen bond between the amino group and the carboxyl­ate fragment. Each coordinating ligand bridges two CdII atoms, thus forming polymeric chains running along the c-axis direction. The water mol­ecules of crystallization serve as donors for the weak inter­molecular O—H⋯O and O—H⋯Br hydrogen bonds that link adjacent polymeric chains, thus forming a three-dimensional structure. N—H⋯O and N—H⋯Br hydrogen bonds also occur.

Semiorganic material of thiosemicarbazide cadmium(II) picrate (TSCPACd) was synthesized. Conductivity measurement was performed using conductivity meter in dimethyl sulfoxide (DMSO) (0.01 g/100 ml). TSCPACd crystallizes in the triclinic space group P-1. FTIR study was carried out in order to confirm the presence of functional groups. UV–vis–NIR spectral studies show that the crystal is transparent in the wavelength range 375–1100 nm. Thermogravimetric and differential thermal analyses reveal the thermal stability of the crystal. The anti-bacterial and anti-fungal activities of the title compound were performed by disk diffusion method against the standard bacteria E. coli, K. pneumonia, and E. faecalis and against the fungus S. aureus, Aspergillus niger and Aspergillus flavus. The compound exhibits good anti-fungal activity.

A new triple-site phase transfer catalyst viz., 1,3,5-tris(ethylmethyleneammonium bromide)-2,4,6-trimethyl benzene (TEMABTB) was prepared by the quaternization of 1,3,5-tris(bromomethyl)-2,4,6-trimethylbenzene using triethylamine and its catalytic efficiency was ascertained by following the kinetics of dichlorocarbene addition of 5-vinyl-2-norbornene. Comparative catalytic activity of various onium salts (single-, di- and tri-site) have been investigated in detail. Based on the kinetic results obtained, a plausible mechanism has been proposed.

An easy access to a hitherto unknown novel multi-site catalyst viz. , 1,3,5-tris(benzyltriethylammonium bromide)benzene (TBTABB) is delineated from low cost starting materials. The structures of the synthesized MPTC's and spiro indene derivative were evidenced by 1 H NMR, 13 CNMR, IR and elemental analysis. The potentiality of the new multi-site phase transfer catalyst was demonstrated by following the kinetics of the cyclopentanation of indene under pseudo-first order conditions by employing aqueous sodium hydroxide and 1,4-dibromobutane in excess. The kinetics of cyclopentanation of indene was carried out at low temperature (40 °C) and was monitored by gas chromatography. Further, the catalytic efficiency of the TBTABB was compared with those of the disite and single-site catalysts by investigating the kinetics of various cyclopentanation reactions. In examining six kinds of phase transfer catalyst, we found TBTABB to be highly efficient. The investigation considered the effects of various experimental parameters and conditions, including agitation speed, concentration of catalyst, concentration of substrate, concentration of sodium hydroxide and temperature on the rate of the reaction. The effect of multi-site phase transfer catalysts on the reaction rate is studied. From the Arrhenius plot, the activation energy was found to be 14.18 kcal mol −1 . Thermodynamic parameters such as Δ S # , Δ G # and Δ H # were also evaluated. Utilizing the kinetic and thermodynamic results, we have proposed an interfacial mechanism for the cyclopentanation of indene. From the different experiments it can be concluded that TBTABB has great potential as a multi-site phase transfer catalyst.

The popularity of triphase catalysis in industries is due to straightforward catalyst recovery from reaction mixture. In this work we report a facile preparation a new polymer-anchored multisite phase transfer catalyst viz., polymer-anchored-2-benzyl-2-phenyl-1,3-bis(triethylmethylene ammonium chloride) (PABPBTAC) using polystyrene-based cross-linked beads. In order to ascertain the catalytic efficiency of the new heterogeneous catalyst, we studied its catalytic activity in the conversion of indene into dichlorocyclopropyl indene using chloroform and sodium hydroxide. Comparative catalytic efficiency of the new polymer-anchored multisite phase transfer catalyst with polymer-supported single site onium salts revealed that the new heterogeneous phase transfer catalyst is highly active than others. Further, from the influence of variation of experimental parameters, such as [substrate], [catalyst], [NaOH], stirring speed and temperature on indene conversion was studied in detail.

This study reports the facile synthesis of a new multi-site phase transfer catalyst, 1,3,5-tris(( N , N , N -triethylammonio)methylphenyl)benzene trichloride (TEAMPBTC). The catalytic potential of this new multi-site phase transfer catalyst was demonstrated by following the kinetics of C-alkylation of dimedone at 50 °C. The influence of various experimental parameters on the rate of the reaction has been investigated in detail. Based on the experimental results, a suitable reaction mechanism is proposed.

The nonlinear optical single crystals of glycine zinc chloride were grown by the slow cooling method from aqueous solution. The title compound was synthesized and purified by repeated recrystallization process. Grown crystals were characterized by X-ray diffraction, FT-IR and FT-Raman spectral analysis. The range and percentage of optical transmission were ascertained by recording UV–Vis–NIR spectrum. Thermal properties were investigated by DTA and TGA analyses. Its second harmonic generation relative efficiency was measured by Kurtz and Perry powder technique using Nd:YAG laser and was observed to be 0.5 times that of potassium dihydrogen orthophosphate. Its mechanical hardness was estimated by Vickers microhardness method.

An ultra wide-band antenna fed by a microstrip line with a U-shaped tuning stub has been developed which provides an impedance bandwidth of 7.2 GHz corresponding to 118 per cent (S11 < –10 dB). The radiation pattern of the antenna is bidirectional. Details of the proposed antenna design have been described and the typical experimental results are presented and discussed.

Glycine zinc sulphate salt was synthesized and the solubility and metastable zonewidth were estimated from the aqueous solution. Single crystals of glycine zinc sulphate were grown by solvent evaporation method from aqueous solution. Grown crystals were characterized by X-ray diffraction and FT-IR spectral analyses. The range and percentage of optical transmission was ascertained by recording UV–vis–NIR spectrum. Thermal properties of the crystal were investigated by thermogravimetric analysis. Microhardness study was carried out on (0 1 −1) face of the grown crystal. Its powder second harmonic generation efficiency was measured using Nd:YAG laser and the value was observed to be 0.7 times that of potassium dihydrogen orthophosphate.

The free radical copolymerization of phenoxyethyl methacrylate (POEMA) and N‐vinyl‐2‐pyrrolidone (Vp) was carried out using α,α′‐azobisisobutyronitrile (AIBN) in 2‐butanone solution at 333 K±1. The copolymers were characterized by FTIR, 1H‐NMR and 13C‐NMR spectroscopic methods. Thermal properties of the copolymers were also studied by thermogravimetric analysis (TGA). The composition of the copolymers was established by 1H‐NMR analysis. The monomer reactivity ratios were computed using the Fineman–Ross (F‐R) and Kelen–Tudos (K‐T) methods. These parameters were also estimated using a non‐linear computational fitting procedure, known as reactivity ratios error in variable model (RREVM). The mean sequence lengths determination indicates that the copolymer was random in nature.

Single crystals Cs{sub 2}Hg{sub 3}I{sub 8} of dimensions 5 × 3 × 4 mm{sup 3} were grown by solution growth method at room temperature and structurally characterized by single crystal X – ray diffraction. Cs{sub 2}Hg{sub 3}I{sub 8} compound crystallizes in a noncentrosymmetric space group Cm with the crystal data of a = 7.4415 A, b = 21.6629 A, c = 7.6726 A, α, β = 90°, γ = 108.05° and Z = 2. The grown crystals were characterized by powder X – ray diffraction analysis and the various diffraction planes are indexed. The presence of functional groups was identified qualitatively by Fourier transform infrared and FT – Raman spectral analyses. Ultraviolet – visible spectral analyses shows that the crystal has low UV cut off at 388 nm combined with very good transparency of 98 % in a wide range. The optical band gap was estimated to be 3 eV. Mechanical hardness of the grown crystal Cs{sub 2}Hg{sub 3}I{sub 8} was determined. The dielectric response of the crystal with varying frequencies was studied. Differential scanning calorimetry (DSC) analysis shows that the grown crystal has very good thermal stability up to 97.5°C.

Single crystal of glycine lithium sulphate, a nonlinear optical material, was grown from aqua solution by temperature reduction method. The solubility and metastable zonewidth of glycine lithium sulphate were estimated using aqueous solution. The cell parameters of the grown crystal were estimated by single crystal X- ray diffraction analysis. The presence of functional groups was identified from FTIR spectrum. Thermal analysis was performed to study the thermal stability of the grown crystal. The transmission and absorption spectra of this crystal show that the lower cut off wavelength lies at 330 nm. Powder Second Harmonic Generation efficiency of the grown crystal measured by Kurtz technique is 0.75 times that of potassium dihydrogen orthophosphate. Vickers microhardness study was carried out on the well developed (011) face of the grown crystal. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

The kinetics of C-alkylation of phenylacetonitrile with 1-bromobutane has been studied using a novel α , α ′, α ″- N -hexakis(triethylammoniummethylene chloride)-melamine as a multi-site phase transfer catalyst (MPTC) using a low concentration of aqueous sodium hydroxide as a base. The reaction was carried out at 50 °C under pseudo-first-order conditions by keeping aqueous base and 1-bromobutane in excess. The formation of the product was monitored by GLC. The effects of various experimental parameters such as [substrate], [NaOH], [catalyst] and temperature on the rate of the reaction have been studied. The results obtained and also the thermodynamic parameters are discussed. The catalytic efficiency of the multi-site catalyst was compared with efficiencies of the commercially available single-site catalysts.