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Purpose: (1) To develop a synchrotron X-ray diffraction (SXRD) method to monitor phase transitions during the entire freeze-drying cycle. Aqueous sodium phosphate buffered glycine solutions with initial glycine to buffer molar ratios of 1:3 (17:50 mM), 1:1 (50 mM) and 3:1 were utilized as model systems. (2) To investigate the effect of initial solute concentration on the crystallization of glycine and phosphate buffer salt during lyophilization., Methods: Phosphate buffered glycine solutions were placed in a custom-designed sample cell for freeze-drying. The sample cell, covered with a stainless steel dome with a beryllium window, was placed on a stage capable of controlled cooling and vacuum drying. The samples were cooled to -50 degrees C and annealed at -20 degrees C. They underwent primary drying at -25 degrees C under vacuum until ice sublimation was complete and secondary drying from 0 to 25 degrees C. At different stages of the freeze-drying cycle, the samples were periodically exposed to synchrotron X-ray radiation. An image plate detector was used to obtain time-resolved two-dimensional SXRD patterns. The ice, beta-glycine and DHPD phases were identified based on their unique X-ray peaks., Results: When the solutions were cooled and annealed, ice formation was followed by crystallization of disodium hydrogen phosphate dodecahydrate (DHPD). In the primary drying stage, a significant increase in DHPD crystallization followed by incomplete dehydration to amorphous disodium hydrogen phosphate was evident. Complete dehydration of DHPD occurred during secondary drying. Glycine crystallization was inhibited throughout freeze-drying when the initial buffer concentration (1:3 glycine to buffer) was higher than that of glycine., Conclusion: A high-intensity X-ray diffraction method was developed to monitor the phase transitions during the entire freeze-drying cycle. The high sensitivity of SXRD allowed us to monitor all the crystalline phases simultaneously. While DHPD crystallizes in frozen solution, it dehydrates incompletely during primary drying and completely during secondary drying. The impact of initial solute concentration on the phase composition during the entire freeze-drying cycle was quantified.

Purpose: To demonstrate the sensitivity of low temperature synchrotron X-ray diffractometry (SXRD) for detecting solute crystallization in frozen sodium phosphate buffer solutions. To determine the effect of annealing on solute crystallization in frozen solutions., Materials and Methods: Sodium phosphate buffer solutions, at initial buffer concentrations ranging from 1 to 100 mM (pH 7.4) were cooled to -50 degrees C. The crystallization of disodium hydrogen phosphate dodecahydrate (Na(2)HPO(4) *12H(2)O) was monitored using a laboratory as well as a synchrotron source. At selected concentrations, the effect of annealing (at -20 degrees C) was investigated., Results: With the laboratory source, solute crystallization, based on the appearance of one diagnostic peak with a d-spacing of 5.4 A, was evident only when the initial buffer concentration was at least 50 mM. In contrast, using SXRD, crystallization was detected at initial buffer concentrations down to 1 mM. In addition, the use of a high-resolution 2D detector enabled the visualization of numerous diffraction rings of the crystalline solute. At both 10 and 100 mM buffer concentration, there was no increase in solute crystallization due to annealing., Conclusion: By using synchrotron radiation, solute crystallization was detected with substantially increased sensitivity, making the technique useful for freeze-drying cycles of practical and commercial importance. Since numerous peaks of the crystalline solute appeared, the technique has potential utility in complex, multi-component systems.

Identification of chemical constituents of calculus is important in the diagnosis and management of urolithiasis. The compositional variability of uroliths has different etiologies and requires various modes of treatment and prophylaxis. In the present study, we report the chemical compositional analyses of calculi recovered from buck and bullock by X-ray diffraction (XRD) and energy dispersive X-ray (EDX) techniques and ultra-structure examination by scanning electron microscopy (SEM). XRD and EDX investigations conclusively established the chemical compositions of urinary calculi under investigation. The calculus from buck (sample I) had calcium oxalate monohydrate, a dominant salt phase and magnesium compound in significant amount. The calculus from bullock (sample II) had magnesium ammonium phosphate phase, with significant amount of calcium in apatite form and K+ ions. SEM study at higher magnification (X 1000) showed bipyramidal crystals in external zones of urolith (sample I). The struvite apatite calculus showed that basic unit of structure was lamination and the laminitis appeared to be made up of fine granules and high porosity. The bio-mineralization process of calculus formation was also studied, with a view to take preventive and therapeutic measures for amelioration of urinary stone diseases in animals and humans.

An efficient green method is developed as a one-pot synthesis of pyrrolo[1,2-c]imidazole-1-one derivatives under microwave conditions via two components in a substoichiometric quantity of water. The conformational and structural studies are conducted through DFT optimization and single crystal X-ray diffraction. The molecular packing is mediated through hydrogen bonding and C–H⋯π interactions. The Hirshfeld surface analysis highlights significant H–H interactions in all compounds, with compound 2a exhibiting the highest percentage. HOMO and LUMO studies reveal compound 2a as more stable and less reactive. The molecular electrostatic potential provides the charged proportionality along with the molecular surface. The drug-likeness properties suggest that compounds 2b, 2c, 2d, 2e, 2f, 2g, and 2i possess favorable properties for potential pharmaceutical applications. [ABSTRACT FROM AUTHOR]

The present study reports an easy eco-friendly, cost efficient, and rapid method for the synthesis of silver nanoparticles (Ag NPs) using palm sprouts as reducing cum capping agent. Green synthesis of silver nanoparticles was successfully performed using palm sprouts plant extract via a simple and cheaper eco-friendly method. Palm sprouts extract reduces silver nitrate to silver nanoparticles. The resulting materials were analyzed by Fourier-transform infrared spectroscopy (FTIR), Scanning Electron Microscopy (SEM), and X-ray Diffraction (XRD) analysis. FT-IR spectrum confirms the presence of various functional groups in the active biomolecules, it acts as a capping agent for the nanoparticles. The morphology of this sample was analyzed through SEM and the presence of silver was confirmed accordingly. The green synthesized Ag NPs exhibited an excellent antibacterial activity against E. coli and P. aeruginosa and B. subtilis and S. aureus besides imparting efficient antimicrobial activity against pathogenic bacteria as well. [ABSTRACT FROM AUTHOR]

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In this present work, graphene supported ruthenium oxide (rGO/RuO2) was synthesized by reflux method. Spectroscopic techniques were used to characterize the synthesized rGO/RuO2 NPs, including Fourier Transform Infrared (FT-IR), Scanning Electron Microscopy (SEM), X-Ray Diffraction (XRD), and Energy-Dispersive X-ray (EDAX). Synthesized rGO/RuO2 NPs that were prepared via reflux method at 150 °C for 3 hours showed a paper like structure with an average crystalline sizes of reduced graphene and rGO/RuO2 was found to be 14 and 10.3 nm. Therefore, the reflux synthesis method, as compared to more complex and time-consuming synthesis methods, can be used to easily and quickly produce high-quality, uniform-sized rGO/RuO2 NPs. The synthesized material has a successful application in electrochemical sensors, photocatalyst, antioxidant, hydrogen generation, used as catalyst in mines, minerals and fuels. [ABSTRACT FROM AUTHOR]

In recent years, compounds from the chalcogenide family have gained importance in thin film technology due to their potential applications in photovoltaic cells, X-ray and gamma-ray detectors. CdZnTe is a II-VI compound semiconductor and is used in photovoltaic solar cells due to its high efficiency and tunable band gap. CdZnTe thin films have properties intermediate between those of CdTe and ZnTe. Their addition creates a common lattice in which the energy band gap is larger than that of ZnTe, making the material more attractive for electronic device fabrication. In this work, CdZnTe films (X = 0.1M, X= 0.2M, and X=0.5M) were deposited on a nickel substrate by chemical bath deposition in a non-aqueous medium. The growth parameters of the CdZnTe film can be adjusted by varying the concentration (X=0.1M, X=0.2M, and X=0.5M) of the Zn content. The varying Zn content regulates the growth rate of CdTe and is an important factor affecting the properties of the film. The chemical bath deposition method was used to vary the different Zn concentrations in the range of 0.1M, 0.2M, and 0.5M, and their effects on various properties of the CdZnTe films were investigated. The effects of Zn doping on the structural, morphological, elemental, and optical properties were studied by XRD, SEM, EDS, FTIR, UV-Visible, and PL. The X-ray diffraction study showed that all films have a cubic zinc-blende structure with a (111) plane. The crystallite size was calculated using the Scherrer formula, and it was found that the crystallite size decreases with increasing Zn content. [ABSTRACT FROM AUTHOR]

Ferrites made of copper substituted Mg0.6-xZn0.4CuxFe2O4 (x = 0.0, 0.1, 0.2 and 0.3) are extremely resistive and magnetic materials. They were produced using the ceramic method, and their structural, compositional, morphological, and functional characteristics were assessed using XRD, SEM, FT-IR, vibrating sample magnetometer (VSM), and dc electrical resistivity, respectively. They belong to the Fd-3m space group and have a spinel structure. After being calcined at 1000 °C, their particle size ranged from 1 to 1.56 μm. With the help of FT-IR analysis, which had absorption bands in the ranges of 570–576 cm−1 and 424–430 cm−1 for higher and lower frequency, respectively, their spinel structure was confirmed. The coercivity coefficient ranges from 73.33 to 154.7 Oe depending on the composition. The highest DC electrical resistivity was found to be 106 Ω-cm at x = 0.1. [ABSTRACT FROM AUTHOR]

The study deals with the isolation, purification and characterization of galactomannan from the endosperm of Borassus labellifer (Linn.) to be used for biomaterial fabrication in tissue engineering (TE) applications. The isolated Borassus flabellifer (Linn.) galactomannan (BFG) through a sequential aqueous dissolution, centrifugation and ethanol precipitation presented a total yield of 19.77 ± 1.05 % (w/w) with advantageous compositional and functional properties. BFG was found to have mannose to galactose (M/G) ratio of 1.4:1. The molecular weight of BFG was found to be 4.9 × 105 g/mol and the molecular structure analysis by FTIR and NMR spectroscopy revealed the presence of α–linked, d -galactopyranose units and β–linked, D-mannopyranose units. Further characterization by rheometer confirmed the non-Newtonian and pseudo-plastic behavior of different BFG concentrations and structural analysis by XRD and SEM confirmed the amorphous nature of BFG with the presence of pores and cervices on the rough surface. Finally, the favorable biological activity demonstrated in response to fibroblast cells against different BFG concentrations substantiates its relevance to be used in biofabrication of tissue scaffolds. [Display omitted] • Galactomannan rich material (BFG) was extracted from B. flabellifer (L.) endosperm by ethanol precipitation. • Extracted BFG had Mw of 4.9 × 105 g/mol with an MG ratio of 1.4:1. • BFG backbone contains α–linked D- galactopyranose and β–linked D-mannopyranose units. • Different BFG concentrations exhibited non-Newtonian and pseudo-plastic behavior. • BFG showed favorable biocompatibility against fibroblast cells. [ABSTRACT FROM AUTHOR]

Abstract New co-crystal containing 5-Fluorouracil (an anticancer drug) as an active pharmaceutical ingredient (API) was prepared by the liquid-assisted grinding method. The prepared co-crystal namely, 5-fluorouracil hydroquinone (5FUHYQ) was studied through single X-ray diffraction. It reveals that the crystal packing is supported by N H⋯O and O H⋯O classical hydrogen bonds forming a sheet-like molecular architecture. The drug molecules are connected themselves through three N H⋯O intermolecular hydrogen bonds leading to two dimeric ring R 2 2(8) motifs. These two ring motifs are placed adjacently forming two chain C 2 1(6) motifs which are running along the a -axis of the unit cell, oppositely. The drug molecules are sandwiched at y = 1/2 and the coformers are placed at y = 0 and 1 making the supramolecular assembly. These ring and chain motifs to form a hydrogen-bonded sheeted. The supramolecular sheets are parallel to (0 4 2 ¯) and (0 4 ¯ 2) planes of the unit cell. This molecular aggregation is replicated in the diffraction pattern as a strong intensity X-ray peaks. The 5FUHYQ has lower calculated density than the parent drug which favour the improved membrane permeability of the drug. Geometrical optimizations of the compound were done by Hartree-Fock (HF) and Density Functional Theory (DFT) using the B3LYP function with the 6-311++G(d,p) basis sets. The optimized molecular geometries and computed vibrational spectra are compared with their experimental counterparts. The Frontier Molecular Orbital (FMO) analysis shows that the present compound has lower band gap value which reiterates the possible pharmaceutical activity of the compound. The anticancer activity of the parent drug is retained against human cervical cancer cell line (HeLa) in this new co-crystalline form. Graphical abstract Image Highlights • Co-crystal of 5-fluorouracil hydroquinone (5FUHYQl) was prepared by the liquid-assisted grinding method. • Classical hydrogen bonds forming a sheet-like molecular architecture. • Geometrical optimizations of the compound were done by Hartree-Fock (HF) and Density Functional Theory (DFT). • Anticancer activity of the parent drug is retained against human cervical cancer cell line. • The Frontier Molecular Orbital (FMO) analysis shows that the present compound has lower band gap value. [ABSTRACT FROM AUTHOR]

Abstract A new stilbene derivative (potential neutraceutical), 1,3-dimethoxy-5-(4-((4-nitrobenzyl)oxy)styryl)benzene (STL) was synthesized, characterized by spectroscopy (1H, 13C NMR and LC-MS) and single crystal X-ray diffraction method. The compound crystallizes in the monoclinic crystal system (space group P2 1∖ c) with unit cell dimensions a = 32.6130(12) Å, b = 7.1894(3) Å, c = 16.7673(6) Å, β = 92.539(3) °, Z = 4, and V = 3927.5(3) Å3. The asymmetric unit consists of two title molecules (A∖B) and the intramolecular hydrogen bonds of the type C H⋯O (A∖B: S (5) ring motif) are observed. The crystal structure is stabilized with C H⋯O (A∖B: C 9 chains) intermolecular hydrogen bonds and short contacts of the type C H ... π (A∖B). The intercontacts in the crystal packing were analyzed using Hirshfeld surfaces method using 2D finger print plots and enrichment ratio (E). The major intercontact contributing to the Hirshfeld surfaces are found to be from H⋯H, O⋯H and C⋯H (A∖B). The favourable contacts responsible for crystal packing (A∖B) are H⋯H, C⋯H, O⋯H and C⋯C confirmed with E values. In addition, the 3D-topology of the crystal packing is analyzed and visualized. The dispersion energy framework contribution is greater than the electrostatic energy frameworks. Graphical abstract Image 1 Highlights • The new stilbene derivative, 1,3-dimethoxy-5-(4-((4-nitrobenzyl)oxy)styryl)benzene (STL) was synthesized. • The three dimensional structure is confirmed by single crystal X-ray diffraction studies. • The C H⋯O (A∖B: C 9 chains) intermolecular hydrogen bonds and short contacts of the type C H ... π are observed. • The crystal packing is analyzed through Enrichment ratio (E) and Energy-framework analysis. • The dispersion energy frameworks dominates the crystal packing. [ABSTRACT FROM AUTHOR]

Single crystals of 2-methoxy-4(phenyliminomethyl)phenol were grown from ethanol by slow evaporation solution growth technique. Single crystal X-ray diffraction experiment reveals the crystallization in orthorhombic system having non-centrosymmetric space group C 222 1 . Geometrical optimization by density functional theory method was carried out using Gaussian program and compared with experimental results. Detailed experimental and theoretical vibrational analyses were carried out and the results were correlated to find close agreement. Thermal analyses show the material is thermally stable with a melting point of 159 °C. Natural bond orbital analysis was carried out to explain charge transfer interactions through hydrogen bonding. Relatively smaller HOMO-LUMO band gap favors the non linear optical activity of the molecule. Natural population analysis and molecular electrostatic potential calculations visualize the charge distribution in an isolated molecule. Calculated first-order molecular hyperpolarizability and preliminary second harmonic generation test carried out using Kurtz-Perry technique establish 2-methoxy-4(phenyliminomethyl)phenol crystal as a good non linear optical material. Z-scan proposes the material for reverse saturable absorption. [ABSTRACT FROM AUTHOR]

Abstract: A new inorganic nonlinear optical single crystal of sodium cadmium tetra chloride (SCTC) is successfully grown from aqueous solution by the slow evaporation technique at room temperature. The crystalline nature of the grown crystal is analyzed by powder X‐ray diffraction. The lattice parameters and crystal system is confirmed by single crystal X‐ray diffraction. Optical transmission study on SCTC crystal shows high transmittance in the entire UV–Vis region. The mechanical strength of the grown crystal is estimated by Vicker's microhardness test. The second harmonic generation (SHG) efficiency of the crystal is measured by Kurtz's powder technique infers that the crystal has nonlinear optical (NLO) efficiency 1.75 times that of KDP. The variation of dielectric constant and dielectric loss as a function of log frequency at various temperature reveals that the crystal shows normal dielectric behaviour. The growth process of SCTC crystal is analysed by etching study. The features of surface of grown crystal is analysed by SEM/EDAX spectrum. The third order nonlinear optical property is investigated for the grown crystal by z – scan technique and the results indicates that SCTC crystal should be a promising material for nonlinear optical device applications. [ABSTRACT FROM AUTHOR]

Electrical and optical studies have been carried out on aluminium-modified Ge2Sb2Te5 thin films to check its applicability as an active material in optical and electrical memory storage devices. Five polycrystalline bulk samples were prepared with compositions: Alx(Ge2Sb2Te5)1-x; x = 0, 0.08, 0.14, 0.21, 0.25. Amorphous thin films were deposited from the polycrystalline bulk by thermal evaporation. Temperature-dependent resistance shows the increase in crystallization temperature of Ge-Sb-Te films on aluminium addition. Activation energy for conduction, conductivity, optical band gap, coefficient of refraction and extinction coefficient are studied with respect to Al content in both amorphous and crystalline phases of Ge-Sb-Te alloy films. [ABSTRACT FROM AUTHOR]

Gadolinium substituted yttrium iron garnet (Gd: YIG: YGdFeO where x = 0, 0.25, 0.5, 0.75, 1, 1.25, 1.5) nanopowders were synthesized by microwave hydrothermal method. Phase structure of synthesized powders was examined using fourier-transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) which revealed a cubic garnet structure. Spherical-like morphology of synthesized powders was confirmed by field emission scanning electron microscopy (FESEM) studies. The synthesized powders were sintered at 1100 °C for 60 min using microwave furnace and characterized by using XRD and FESEM. Magnetic properties such as saturation magnetization and Curie temperature were measured using vibration sample magnetometer (VSM) and differential scanning calorimetry (DSC) studies respectively. Temperature stability of magnetization was measured using pulse magnetometer and complex permeability was measured over a frequency range of 100 kHz-1.8 GHz. The obtained results showed that the saturation magnetization as well as permeability decrease while curie temperature and temperature stability increase with Gd concentration. It is concluded that substitution of Gd makes the YIG better microwave magnetic material, which may be used in high power non-reciprocal microwave devices in the microwave region. [ABSTRACT FROM AUTHOR]

The N,N-dimethylethylamminium unit in N,N-dimethyl-[2-(2,2-diphenyl)-2- prop-2-ynyloxyacetoxy]ethylamine, C21H23NO3 (I), is disordered over two sets of atomic sites having occupancies of 0.880 (3) and 0. 120 (3), but there are no direction-specific interactions between the molecules of (I). The cation in N,Ndimethyl-[ 2-(2,2-diphenyl)-2-prop-2-ynyloxyacetoxy]ethylammonium 2,4,6-trinitrophenolate (picrate), C21H24NO3+⋅C6H2N3O7- (II), shows a similar type of disorder, with occupancies of 0.654 (11) and 0.346 (11), although the overall conformation of the cation in (II) is different from that in the neutral (I). The component ions are are linked by an almost planar three-centre N--H ⋯ (O)2 hydrogen bond, and the ion pairs are further linked by a combination of three C--H ⋯ O hydrogen bonds to form sheets. Comparisons are made with some related structures. [ABSTRACT FROM AUTHOR]

New organic non-linear optical (NLO) single crystals of guanidinium cinnamate were crystallized by solvent evaporation solution growth technique and the crystal and molecular structure were determined by single crystal X-ray diffraction. The crystal packing is dominated by classical N-H···O hydrogen bonding interactions. Due to deficiency of acceptor atoms compared to the donor sites, two unusual ring R (6) motifs are formed through two N-H···O hydrogen bonds. These ring motifs are further connected through chain C (6) or C (8) motifs along the b-axis of the unit cell. Further, these chain and ring motifs are cross-linked through another N-H···O hydrogen bond leading to classical ring R (8) motif. These chain and ring motifs are interlinked with each other to form secondary ring R (14)/R (16) motifs. The molecular geometry of the asymmetric part of the unit cell was optimized theoretically by density functional theory using the B3LYP function with 6-311 + + G(d,p) basis set. The optimized molecular geometry and computed vibrational spectra are compared with experimental results which showed significant agreement. The intermolecular interactions of the title compound were analyzed by the Hirshfeld surfaces. The computed hyperpolarizability values showed that the compound is a good candidate for NLO applications. The chemical hardness, electro-negativity and chemical potential of the molecule were computed by HOMO-LUMO plot. The lower band gap of the frontier orbitals indicates the suitability of fabrication of the material for non-linear optoelectronic applications. [ABSTRACT FROM AUTHOR]

Laser-induced crystallization is emerging as a promising technique to crystallize biomolecules like amino acids and proteins. The use of external materials as nucleants and novel seeding methods open new paths for protein crystallization. We report here the results of experiments that explore the effect of nucleants on laser-based crystallization of microlitre droplets of small molecules, amino acids, and proteins. The role of parameters like solute concentration, droplet volume, type and size of the nucleant, and laser power, are systematically investigated. In addition to crystallization of standard molecules like NaCl, KCl, and glycine, we demonstrate the crystallization of negatively (l-histidine), and positively (l-aspartic acid) charged amino acids and lysozyme protein. Single crystal X-ray diffraction and Raman spectroscopy studies unequivocally indicate that the nucleants do not alter the molecular structure of glycine, hydrogen bonding patterns, and packing. Localized vaporization of the solvent near the nucleant due to photothermal heating has enabled us to achieve rapid crystallization – within 3 s – at laser intensities of 0.1 MW cm−2, significantly lower than those reported earlier, with both saturated and unsaturated solutions. The outcome of the current experiments may be of utility in tackling various crystallization problems during the formation of crystals large enough to perform X-ray crystallography. [ABSTRACT FROM AUTHOR]

Homogeneous and non-agglomerative Ce:LuAG nanoparticles with different Ce 3 + doping concentrations ( 0.05, 0.10 and 0.15 mol% ) were prepared by surfactant free aqueous precipitation synthesis via low temperature refluxer route. The synthesized powders are post calcined at 900 °C and 1300 °C for 4 h; and characterized by thermo-gravimetric (TG), differential scanning calorimetry (DSC), X-ray diffraction (XRD), high resolution scanning electron microscopy (HR-SEM), high resolution transmission electron microscopy (HR-TEM), photoluminescence (PL), decay life-time (DLT) and thermoluminescence (TL) techniques. XRD result confirms the formation of cubic phase without the evolution of any intermediate and secondary phases. HR-SEM shows that the nanoparticles synthesized by the surfactant-free approach resulted in non-agglomerated spheroidal morphology. An attempt is also made to calculate grain boundary diffusion (D gb ) parameter of Ce:LuAG nanoparticles observed from TEM nano-particulate necking morphology. The nanophosphor exhibit enhanced green luminescence (λ em = 505 nm) under blue light excitation (λ ex = 450 nm). The TL behavior is also investigated under the exposure of γ-ray ( 60 Co) source. TL dosimetric parameters such as order of kinetics (μ g ), activation energy (E) and frequency factor (S) are calculated using Chen's equation. The fast DLT of ~ 17 ns observed in the Ce:LuAG nanophosphors can be useful for scintillators and fluorescent device applications. [ABSTRACT FROM AUTHOR]

In the present work, a new co-crystal of nicotinic acid with pyrogallol (NICPY) has been grown in the zwitterionic form and the corresponding structural, vibrational, thermal, solubility and anti-cancer characteristics have been reported. The single crystal X-ray diffraction analysis confirms that the structural molecular packing of the crystal stabilized through N–H⋯O and O–H⋯O hydrogen bond. The stabilization energy of the hydrogen bond motifs were calculated in the solid state. Vibrational spectral studies such as Fourier transform-infrared (FT-IR) and FT-Raman were adopted to understand the zwitterionic co-crystalline nature of the compound, which has been compared with theoretically calculated vibrational frequencies. The thermal stability of the grown co-crystal was analyzed by TG/DTA study. The solubility of the NICPY co-crystal was investigated in water at different temperature and compared with that of the nicotinic acid, which is the parent compound of NICPY co-crystal. The grown crystals were treated with human cervical cancer cell line (HeLa) to analyze the cytotoxicity of NICPY crystals and compared with the parent compound, which shows that NICPY has moderate activity against human cervical cancer cell line. [ABSTRACT FROM AUTHOR]

Nanocrystalline Ceria (CeO) was synthesized through auto-ignited combustion technique. The X-ray diffraction studies of CeO nanoparticles have shown that the as-prepared powder was single phase, crystalline and has a face centred cubic structure. The phase purity of the powder was further examined using Fourier Transform Infrared and Raman spectroscopic techniques. The transmission electron microscopic studies have shown that the particle size of the as prepared powder was in the range of 30-40 nm. The band gap of nanoparticles as calculated from the absorption spectrum was found to be 3.51 eV. The photoluminescent spectrum of the samples exhibited a number of emission peaks which forms a broad band emission between 400 and 500 nm originating from T(5d)-F, F(4f) transition of Ce ion due to spin-orbit coupling under the influence of O crystal field. The nanopowders were sintered to about 95 % of the theoretical density at 1450 °C for 2 h. The microstructure of the sintered surface was examined using scanning electron microscopy. The dielectric constant (ε) and loss tangent (tanδ) at 5 MHz are found to be about 25.1 and 0.0118 respectively. The complex impedance plots show semicircular arcs resolving at high temperature which confirms the existence of the non-Debye type of relaxation in the sintered CeO samples. [ABSTRACT FROM AUTHOR]

Elastomeric composites based on nitrile rubber (NBR), carbon black (CB), and organically modified nanoclay (NC) were prepared using a laboratory two-roll mixing mill. Influences of the hybrid filler system (CB+NC) on various properties of NBR compound were analyzed. It was found that the addition of hybrid filler (CB+NC) over only carbon black enhances various properties. It was also found that the addition of nanoclay to the rubber matrix effectively improved key properties. Acoustics and electrical properties were modified with reduced water absorption because of layered clay platelets. The lower volume resistivity of NBR composites reflected better electrical conductivity attributed to the presence of nanoclay leading to effective filler connectivity. X-ray diffraction and transmission electron microscopy measurements revealed that nanoclays were mostly intercalated and were uniformly dispersed. Use of calcium stearate facilitated dispersion of nanoclay in the rubber matrix which was observed through the formation of nanostructures including 'nano' and 'halo' units. Time temperature superposition in dynamic mechanical analysis test of the composites indicated lower mechanical loss in the frequency range of interest. The advantages accruing due to overall property enhancement, including lower water absorption, and better electrical and excellent acoustic properties of NBR composites make it suitable as underwater acoustic transparent materials for transducer encapsulation application. POLYM. COMPOS., 37:1786-1796, 2016. © 2014 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

Unsymmetrical (N,C,E)-type pincer ligand precursors [L1 and L2: E = S/Se] with an indole core were synthesized for the first time by the condensation of 1-(2-phenylsulfanyl/selenylethyl)-1H-indole-3-carbaldehyde with benzyl amine. The synthetic protocols are easy and give good yields (＞85%). L1 and L2 on reaction with sodium tetrachloropalladate(ii) in the presence of CH3COONa result in complexes [Pd(L1/L2–H)Cl] (1/2), where they bind in a tridentate (N,C−,E) mode. L1 and L2, their aldehyde precursors and Pd(ii)-complexes, 1 and 2, have been characterized by 1H, 13C{1H} and 77Se{1H} NMR and HR-MS. Palladium(ii) complexes 1 and 2 and precursor aldehydes of L1 and L2 were verified using single crystal X-ray diffraction. The catalytic activities of complexes 1 and 2 were investigated for Heck coupling and allylation of aldehydes. The two reactions require 0.1–0.3 and 1 mol% loading of complexes as catalysts, respectively. [ABSTRACT FROM AUTHOR]

Apara-nitrophenol sensor based on a 5-sulfosalicylic acid doped polyaniline nanorods modified glassy carbon electrode is reported. The formation of 5-sulfosalicylic acid doped polyaniline was characterized by Fourier transform infrared spectroscopy, ultraviolet-visible spectroscopy, X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. The electroactivity of the 5-sulfosalicylic acid doped polyaniline nanorods was studied by cyclic voltammetry and differential pulse voltammetry and high response was observed for the reduction ofpara-nitrophenol. The calibration curve forpara-nitrophenol was linear from 6.7 × 10−6 M to 112.1 × 10−6 M. The sensitivity and limit of detection were 24 nA µM−1and 3.2 × 10−6 M, respectively. The sensor was simple, inexpensive, and employed for the determination ofpara-nitrophenol in tap water with recoveries from 97.6 to 101.0%. [ABSTRACT FROM PUBLISHER]

The new semi-organic crystal of 4-aminium antipyrine chloride was grown as a single crystal by slow evaporation solution growth method. The crystal and molecular structure of the grown crystal was determined by single crystal diffraction techniques. The single crystal XRD studies reveal that the phenyl ring and pyrazolone ring of the cation has been inclined at an angle of 52.3 (1)°. The molecular aggregations were stabilized through intricate three dimensional hydrogen bonding network formed by the classical N–H⋯O and N–H⋯Cl hydrogen bonds. The cationic dimer R 2 2 (10) motif formed through N–H⋯O intermolecular hydrogen bonds was observed around the inversion center of the unit cell. The amino group from the cation and the chlorine anion was linked through N–H⋯Cl intermolecular hydrogen bond leading to a R 2 4 (8) ring motif. These two ring motifs were extended along the a -axis of the unit cell and forms a hydrophilic layer at z = 0 and 1, which is sandwiched between the hydrophobic layer at z = 1/2. Geometry optimization of the molecules was done by Density Functional Theory (DFT) using the B3LYP function and Hartree–Fock (HF) level with 6-311++G(d,p) basis set. The optimized molecular geometry and computed vibrational spectra were compared with experimental results which show a significant agreement. The natural bond orbital (NBO) analysis was carried out to interpret hyperconjucative interaction and intramolecular charge transfer (ICT). The chemical hardness, electro-negativity and chemical potential of the molecule were carried out by HOMO-LUMO plot. The lower band gap value of the frontier orbitals shows the possible bioactivity of the molecule. [ABSTRACT FROM AUTHOR]

The single crystal of the hydrated anticancer drug, 6-Mercaptopurine (6-MP), has been grown by slow evaporation technique under room temperature. The structure was determined by single crystal X-ray diffraction. The vibrational spectral analysis was carried out using Laser Raman and FT-IR spectroscopy in the range of 3300–100 and 4000–400 cm −1 . The single crystal X-ray studies shows that the crystal packing is dominated by N–H⋯O and O–H⋯N classical hydrogen bonds leading to a hydrogen bonded ensemble. This classical hydrogen bonds were further connected through O–H⋯S hydrogen bond to form two primary ring R 4 4 (16) and R 4 4 (12) motifs. These two primary ring motifs are interlinked with each other to build a ladder like structure. These ladders are connected through N–H⋯N hydrogen bond along c -axis of the unit cell through chain C(5) motifs. Further, the strength of the hydrogen bonds is studied through vibrational spectral measurements. The shifting of bands due to the intermolecular interactions was also analyzed in the solid crystalline state. Geometrical optimizations of the drug molecule were done by Density Functional Theory (DFT) using the B3LYP function and Hartree–Fock (HF) level with 6-311++G(d,p) basis set. The optimized molecular geometry and computed vibrational spectra are compared with experimental results which show significant agreement. The natural bond orbital (NBO) analysis was carried out to interpret hyperconjugative interaction and intramolecular charge transfer (ICT). The chemical hardness, electro-negativity and chemical potential of the molecule are carried out by HOMO–LUMO plot. In which, the frontier orbitals has lower band gap value indicating the possible pharmaceutical activity of the molecule. [ABSTRACT FROM AUTHOR]

Natural bitumen which is generally used for highway paving has a short life cycle, due to traffic load and drastic change of pressure and temperature. To get the appropriate physical properties of this bitumen, it is generally modified by using reactive molecules. In this study, glycerol, styrene, methyl methacrylate (MMA), hydroquinone (HQ), and C18 acrylate molecules are used as modifiers. The required amounts of the modifier and bitumen are heated at 200 °C for 8 h with continuous stirring. The asphaltene is extracted from these modified bitumen by soxhlet process. The physical properties of the dried asphaltene are characterized by XRD, SEM and TGA. Results show that the hardness properties, like penetration, softening point, ductility of the natural bitumen are substantially improved after treatment with the modifiers. XRD results indicate that asphaltenes extracted from the modified bitumens become more compact than the asphaltene from the natural bitumen. The results also show that the number of aromatic sheets increases due to the treatment of natural bitumen with the modifiers. The asphaltene derived from C18-acrylate modified bitumen has the maximum number of aromatic sheets. The presence of vinyl double bond and –COOR functional group in C18-acrylate helps effectively the polymerization reaction between the modifier and the natural bitumen. SEM and TGA results also support the presence of a high degree of polymerization/structural arrangement in the asphaltene obtained from this modified bitumen. [ABSTRACT FROM AUTHOR]

The optical properties of nanocrystalline HfO2 synthesized using a single-step auto-igniting combustion technique is reported. Nanocrystalline hafnium oxide having particle size of the order 10-15 nm were obtained in the present method. The nanopowder was characterized using X-ray diffraction, Fourier transform infrared and Fourier transform Raman spectroscopic studies. All these studies confirm that the phase formation is complete in the combustion synthesis and monoclinic phase [P21/c(14)] of HfO2 is obtained without the presence of any impurities or additional phases. The powder morphology of the as-prepared sample was studied using transmission electron microscopy and the results were in good agreement with that of the X-ray diffraction studies. The optical constants such as refractive index, extinction coefficient, optical conductivity and the band gap were estimated from UV-vis spectroscopic techniques. The band gap of nanocrystalline HfO2 was found to be 5.1 eV and the sample shows a broad PL emission at 628 nm. It is concluded that the transitions between intermediate energy levels in the band gap are responsible for the interesting photoluminescent properties of nanocrystalline HfO2. [ABSTRACT FROM AUTHOR]

Hierarchical mesoporous NiO nanoflakes (NiOs) have been synthesized in high yield via a simple, economical and environmentally friendly hydrothermal route. The as-prepared NiOs were characterized by powder X-ray diffraction (PXRD), scanning electronic microscopy (SEM), transmission electron microscopy (TEM), selected area electron diffraction patterns (SAED), X-ray energy dispersive spectroscopy (EDS) and nitrogen adsorption-desorption techniques (Brunauer-Emmett-Teller, BET). Adsorption of heavy metal ions onto the as-prepared sample from aqueous solutions was investigated using differential pulse anodic stripping voltametry (DPASV) technique and discussed. The product possesses a BET surface area of 69.27 m g. It is found that NiOs exhibited the excellent performance for the removal of Hg(II), Pb(II) and Cd(II) from aqueous solution. The equilibrium adsorption data of Hg(II), Pb(II) and Cd(II) on the as-prepared NiOs were analyzed by Langmuir and Freundlich models, suggesting that the Langmuir model provides the better correlation of the experimental data. The adsorption capacities for removal of Hg(II), Pb(II) and Cd(II) were determined using the Langmuir equation and found to be 1324 .5, 1428 .9 and 1428 .5 mg g, respectively. Adsorption kinetics of all the metal ions followed pseudo second-order model. Moreover, NiOs can be recycled by simple acid treatment, which could retain the high removal efficiency in three successive cycles. This study suggests that nanoflakes could be explored as a new adsorbent with high efficiency and recyclability for removing heavy metal ions from aqueous solution. [ABSTRACT FROM AUTHOR]

The compound (Z)-2-(3-chlorophenyl)-N’-hydroxyacetamidine, (2) was synthesized and characterized by1H NMR, FT-IR, TGA, UV-Visible Spectra, and elemental analysis. Its molecular structure was solved by single-crystal X-ray diffraction method. The title molecule, C8H9ClN2O is crystallized in the monoclinic crystal system with the space group P21/c and with unit cell parameters a = 8.7092(4) Å, b = 8.2370(4) Å, c = 12.5256(6) Å,β= 102.252(3)°, and Z = 4. The molecular and crystal structure of the title molecule is stabilized by an intramolecular interaction of the type N—HċċċO, and the intermolecular interactions of types N—HċċċN and O—HċċċN. [ABSTRACT FROM AUTHOR]

In this study, copper oxide nanoparticles with hierarchical morphologies (CuO) have been synthesized via a hydrothermal route. The morphology and microstructure of the as prepared samples were characterized by XRD, SEM, TEM, and SAED. CuO exhibited excellent performance for the removal of Pb(II) from aqueous solution. The effects of initial Pb(II) concentration and contact time on CuO were investigated from batch tests. The results indicate that the equilibrium adsorption data were best fitted by the Langmuir isothermal model, with the maximum adsorption capacity of 1428.5 mgg−1which is found to be one of the highest values reported elsewhere in the literature; adsorption kinetics follows the pseudo-second-order kinetic equation and intra-particle diffusion model. A possible adsorption mechanism was predicted by using FTIR, EDX techniques. Large adsorption capacity for heavy metal ion and effective regeneration ability suggesting CuO is a very promising adsorbent for metal ion removal and wastewater cleanup. [ABSTRACT FROM PUBLISHER]

The microstructural evolution during twin roll casting (TRC) and downstream processing of AA5754 Al alloy with high added impurity content have been investigated. Strip casts with a high impurity content resulted in coarse α-Al grains and complex secondary phases. The grain size and centerline segregation reduced significantly on the addition of Al-Ti-B grain refiner (GR). Coarse-dendrite arm spacing (DAS) 'floating' grains are observed in the impure alloy (IA) with higher volume in the GR strips. Two-dimensional (2D) metallographic analysis of the as-cast strip suggests that secondary phases (Fe-bearing intermetallics and MgSi) are discrete and located at the α-Al cell/grain boundaries, while three-dimensional (3D) analysis of extracted particles revealed that they were intact, well interconnected, and located in interdendritic regions. Homogenizing heat treatment of the cast strip breaks the interconnective networks and modifies the secondary phases to a more equiaxed morphology. During rolling, the equiaxed secondary phases align along the rolling direction. X-ray diffraction (XRD) analysis suggests that α-Al(FeMn)Si and MgSi are the predominant secondary phases that are formed during casting and remain throughout the downstream processing of the GR-IA. The high-impurity sheet processed from TRC resulted in superior strength and ductility over the sheet processed from small book mold ingot casting. The current study has shown that the TRC process can tolerate higher impurity levels and produce formable sheets from the recycled aluminum for structural applications. [ABSTRACT FROM AUTHOR]

Copper vanadate (CuVO) nanoparticles were synthesized by a simple thermal decomposition method. The synthesized copper vanadate nanorods were characterized by X-ray diffraction analysis, and it is found that the synthesized sample belongs to monoclinic CuVO. Fourier transform infrared spectroscopy (FT-IR) confirms the formation of Cu-O bond in the sample. Ultraviolet-visible (DRS-UV-visible) spectroscopy and photoluminescence spectroscopy reveals the optical property of the CuVO nanoparticles. The nanobar-like morphology was confirmed by both scanning electron microscopy and high resolution transmission electron microscopy. Further, the electrochemical sensing behavior of CuVO nanoparticles was investigated by cyclic voltammetry using lidocaine as an analyte. The electrochemical sensing experiment suggests that the CuVO nanoparticles will become a potential candidate in the field of drug sensor. [ABSTRACT FROM AUTHOR]

Polyvinyl alcohol (PVA) doped (Se80Te20)100–xAgx(0 ≤x≤ 4) thin films were prepared by the spin-coating technique on a quartz substrate. The optical parameters of PVA-doped (Se80Te20)100–xAgx(0 ≤x≤ 4) composites at the same chalcogen concentration (S0= 0.1 mg ml−1) and PVA/(Se80Te20)96Ag4composites at three different chalcogen concentrations viz.S1= 0.3 mg ml−1, S2= 0.6 mg ml−1and S3= 1 mg ml−1have been studied. The semi-crystalline nature of the as-deposited thin filmsisdetermined by X-ray diffraction. The transmission and reflection spectra of PVA-doped Se–Te–Ag thin films were obtained in a 350–650 nm spectral region. The optical-band gap has been calculated from the transmission and reflection data. The refractive index has been calculated by the measured reflection data. It has been found that the optical-band gap increases, but the refractive index, extinction coefficient, and the real and imaginary parts of the dielectric constant decrease, with increase in Agcontent in PVA-doped (Se80Te20)100–xAgx(0 ≤x≤ 4) thin films. Such type of behavior is explained on the basis of decrease in density of the defect states. However, the optical-band gap has been found to be decreased and all other optical parameters show increase in their values with increase in concentration of (Se80Te20)96Ag4glass in PVA-doped composites. The results have been explained on the basis of cluster-size formation at the time of dissolution. This study shows that the optical properties of new composites are affected by the change in silver and chalcogen concentration. [ABSTRACT FROM AUTHOR]

Present work reports the effect of substrate on the optical properties of Se92Te4Ag4thin films. Thin films of thickness 2500 Å were prepared by the thermal evaporation of the bulk samples. Amorphous nature of thin films is confirmed by the X-ray diffraction spectra. The transmittance spectra of Se92Te4Ag4thin films were obtained in the spectral region in the range 300–1100 nm. The optical band gap (Eg) and extinction coefficient (k) has been calculated from the absorbance data. The value of refractive index (n) has been determined from Swanepoel's method. The band gap of the film deposited on mica substrate (1.24 eV) is smallest as compared to the band gap of the films deposited on microscopic glass (1.29 eV) and quartz (1.26 eV). The change in value of optical parameters with change in substrate is explained in terms of disorder and defects, which confirms the dependence of optical parameters on types of substrates. [ABSTRACT FROM AUTHOR]