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Sample records for synthesis characterization crystal

  1. Synthesis and characterization of hydroxyapatite crystals: a review study on the analytical methods

    NARCIS (Netherlands)

    Koutsopoulos, S.

    2002-01-01

    For the synthesis of hydroxyapatite crystals from aqueous solutions three preparation methods were employed. From the experimental processes and the characterization of the crystals it was concluded that aging and precipitation kinetics are critical for the purity of the product and its

  2. Synthesis and structural characterization of bulk Sb2Te3 single crystal

    Science.gov (United States)

    Sultana, Rabia; Gahtori, Bhasker; Meena, R. S.; Awana, V. P. S.

    2018-05-01

    We report the growth and characterization of bulk Sb2Te3 single crystal synthesized by the self flux method via solid state reaction route from high temperature melt (850˚C) and slow cooling (2˚C/hour) of constituent elements. The single crystal X-ray diffraction pattern showed the 00l alignment and the high crystalline nature of the resultant sample. The rietveld fitted room temperature powder XRD revealed the phase purity and rhombohedral structure of the synthesized crystal. The formation and analysis of unit cell structure further verified the rhombohedral structure composed of three quintuple layers stacked one over the other. The SEM image showed the layered directional growth of the synthesized crystal carried out using the ZEISS-EVOMA-10 scanning electron microscope The electrical resistivity measurement was carried out using the conventional four-probe method on a quantum design Physical Property Measurement System (PPMS). The temperature dependent electrical resistivity plot for studied Sb2Te3 single crystal depicts metallic behaviour in the absence of any applied magnetic field. The synthesis as well as the structural characterization of as grown Sb2Te3 single crystal is reported and discussed in the present letter.

  3. CsPb2Br5 Single Crystals: Synthesis and Characterization

    KAUST Repository

    Dursun, Ibrahim

    2017-08-02

    CsPb2Br5 is a ternary halogen-plumbate material with close characteristics to well-reported halide perovskites. Due to its unconventional two-dimensional structure, CsPb2Br5 is being looked at broadly for potential applications in optoelectronics. CsPb2Br5 investigations are currently limited to nanostructures and powder forms of the material, which present unclear and conflicting optical properties. In this study, we present the synthesis and characterization of CsPb2Br5 bulk single crystals, which enabled us to finally clarify the material\\'s optical features. Our CsPb2Br5 crystal has a two-dimensional structure with Pb2Br5- layers spaced by Cs+ cations, and exhibits a ~3.1 eV indirect bandgap with no emission in the visible spectrum.

  4. Synthesis, Characterization and Applications in Catalysis of Polyoxometalate/Zeolite Composites

    Directory of Open Access Journals (Sweden)

    Frédéric Lefebvre

    2016-05-01

    Full Text Available An overview of the synthesis, characterization and catalytic applications of polyoxometalates/zeolites composites is given. The solids obtained by direct synthesis of the polyoxometalate in the presence of the zeolite are first described with their applications in catalysis. Those obtained by a direct mixing of the two components are then reviewed. In all cases, special care is taken in the localization of the polyoxometalate, inside the zeolite crystal, in mesopores or at the external surface of the crystals, as deduced from the characterization methods.

  5. Synthesis and characterization of activated lithium fluoride with silver

    International Nuclear Information System (INIS)

    Encarnacion E, E. K.; Guerrero S, Z.; Reyes A, J.

    2017-10-01

    The present work shows part of the results obtained in the development of the research that has been carried out since 2015 entitled -Synthesis and characterization of new thermoluminescent materials for the radiation dosimetry and its applications in health-. In the development of this research, the synthesis of crystals of pure lithium fluoride (LiF) and activated with different concentrations of silver (LiF:Ag); synthesized samples are also presented using different temperatures, as well as varying the concentration of the solvent (water-ethanol). The synthesized materials were characterized through different techniques: scanning electron microscopy and X-ray diffraction. Specifically, the results of the calculation of the size of the LiF crystals are presented using the Scherrer equation. Within the results, a dependence on the size of the crystals is highlighted by means of the following factors: the amount of activator in the sample, the temperature at which the sample was synthesized, as well as the amount of solvent in the synthesis. The samples have a simple cubic crystalline phase. (Author)

  6. Study of the influence in crystallization period in MCM-22 zeolite synthesis

    International Nuclear Information System (INIS)

    Barbosa, A.S.; Santos, E.R.F.; Rodrigues, M.G.F.

    2011-01-01

    The synthesis of MCM-22 is accomplished by hydrothermal treatment and long periods needed for crystallization, with the gradual growth of crystals of 10-14 days. MCM-22 catalyst is studied intensively as promising, with high thermal stability. As part of a line of research focused on the development of zeolite with lowest cost, this study aimed to examine the effect in decreasing the period of crystallization in the synthesis of zeolite MCM-22. The materials were characterized by X-ray diffraction (XRD) spectroscopy, X-ray Energy Dispersive (EDX) and Fourier transform infrared spectroscopy and Fourier transform (FT-IR). By XRD it was observed that the hydrothermal treatment used in the synthesis was effective during periods of crystallization and EDX was observed that the samples have a high percentage of silica and low alumina content, which gives them a high ratio SiO 2 /Al 2 O 3 characteristic of the MWW structure. (author)

  7. Thorium/uranium mixed oxide nano-crystals: Synthesis, structural characterization and magnetic properties

    International Nuclear Information System (INIS)

    Hudry, Damien; Griveau, Jean-Christophe; Apostolidis, Christos; Colineau, Eric; Rasmussen, Gert; Walter, Olaf; Wang, Di; Venkata Sai Kiran Chakravadhaluna; Courtois, Eglantine; Kubel, Christian

    2014-01-01

    One of the primary aims of the actinide community within nano-science is to develop a good understanding similar to what is currently the case for stable elements. As a consequence, efficient, reliable and versatile synthesis techniques dedicated to the formation of new actinide-based nano-objects (e.g., nano-crystals) are necessary. Hence, a 'library' dedicated to the preparation of various actinide based nano-scale building blocks is currently being developed. Nano-scale building blocks with tunable sizes, shapes and compositions are of prime importance. So far, the non-aqueous synthesis method in highly coordinating organic media is the only approach which has demonstrated the capability to provide size and shape control of actinide-based nano-crystals (both for thorium and uranium, and recently extended to neptunium and plutonium). In this paper, we demonstrate that the non-aqueous approach is also well adapted to control the chemical composition of the nano-crystals obtained when mixing two different actinides. Indeed, the controlled hot co-injection of thorium acetylacetonate and uranyl acetate (together with additional capping agents) into benzyl ether can be used to synthesize thorium/uranium mixed oxide nano-crystals covering the full compositional spectrum. Additionally, we found that both size and shape are modified as a function of the thorium/uranium ratio. Finally, the magnetic properties of the different thorium/uranium mixed oxide nano-crystals were investigated. Contrary to several reports, we did not observe any ferromagnetic behavior. As a consequence, ferromagnetism cannot be described as a universal feature of nano-crystals of non-magnetic oxides as recently claimed in the literature. (authors)

  8. Synthesis and Characterization of Novel Quaternary Thioaluminogermanates

    KAUST Repository

    Al-Bloushi, Mohammed

    2013-05-01

    Metal chalcogenides form an important class of inorganic materials, which include several technologically important applications. The design of metal chlcogenides is of technological interest and has encouraged recent research into moderate temperature solid-state synthetic methods for the single crystal growth of new materials. The aim of this project is the investigation and development of synthetic methodology for the synthesis of novel metal chlcogenides. The new inorganic compounds of the type “M(AlS2)(GeS2)” (M = Na and K) are new metal-chalcogenides, synthesized by the classical solid state approach. The characterization of these compounds was carried out by Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectroscopy (EDS), Single crystal and powder X-ray diffraction, solid state Nuclear Magnetic Resonance (NMR), Ultraviolet-visible (UV-VIS), Infrared (IR) and Raman spectroscopy. These theses study the synthesis of metal chalcogenides through the use of standard chemical techniques. The systematic studies demonstrate the effect of the reactants ratio and reaction temperature on the synthesis and growth of the single crystals. Metal chalcogenides have several potential applications in gas separation, ion exchange, environmental remediation, and energy storage. Especially, the ion exchange materials have found\\tpossible applications in waste-water treatment, water softening, metal separation, and production of high purity water.

  9. Single-crystal apatite nanowires sheathed in graphitic shells: synthesis, characterization, and application.

    Science.gov (United States)

    Jeong, Namjo; Cha, Misun; Park, Yun Chang; Lee, Kyung Mee; Lee, Jae Hyup; Park, Byong Chon; Lee, Junghoon

    2013-07-23

    Vertically aligned one-dimensional hybrid structures, which are composed of apatite and graphitic structures, can be beneficial for orthopedic applications. However, they are difficult to generate using the current method. Here, we report the first synthesis of a single-crystal apatite nanowire encapsulated in graphitic shells by a one-step chemical vapor deposition. Incipient nucleation of apatite and its subsequent transformation to an oriented crystal are directed by derived gaseous phosphorine. Longitudinal growth of the oriented apatite crystal is achieved by a vapor-solid growth mechanism, whereas lateral growth is suppressed by the graphitic layers formed through arrangement of the derived aromatic hydrocarbon molecules. We show that this unusual combination of the apatite crystal and the graphitic shells can lead to an excellent osteogenic differentiation and bony fusion through a programmed smart behavior. For instance, the graphitic shells are degraded after the initial cell growth promoted by the graphitic nanostructures, and the cells continue proliferation on the bare apatite nanowires. Furthermore, a bending experiment indicates that such core-shell nanowires exhibited a superior bending stiffness compared to single-crystal apatite nanowires without graphitic shells. The results suggest a new strategy and direction for bone grafting materials with a highly controllable morphology and material conditions that can best stimulate bone cell differentiation and growth.

  10. Synthesis of SAPO-56 with controlled crystal size

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Ting; Feng, Xuhui [Colorado School of Mines, Chemical and Biological Engineering Department (United States); Carreon, Maria L. [University of Tulsa, Rusell School of Chemical Engineering (United States); Carreon, Moises A., E-mail: mcarreon@mines.edu [Colorado School of Mines, Chemical and Biological Engineering Department (United States)

    2017-03-15

    Herein, we present the hydrothermal synthesis of SAPO-56 crystals with relatively controlled crystal/particle size. The effects of water content, aluminum source, gel composition, stirring, crystallization temperature and time, as well as the incorporation of crystal growth inhibitors during synthesis were systematically investigated. The synthesized SAPO-56 crystals displayed BET surface areas as high as ∼630 m{sup 2} g{sup −1} with relative narrow size distribution in the ∼5–60 μm range. Nitrogen BET surface areas in the 451 to 631 m{sup 2} g{sup −1} range were observed. Decreasing the crystallization temperature from 220 to 210 °C helped to decrease the average SAPO-56 crystal size. Diluted gel compositions promoted the formation of smaller crystals. Crystal growth inhibitors were found to be helpful in reducing crystal size and narrow the size distribution. Specifically, ∼5 μm SAPO-56 crystals displaying narrow size distribution were synthesized employing aluminum-tri-sec-butoxide as Al source, high water content, and high stirring rates.

  11. Synthesis of SAPO-56 with controlled crystal size

    International Nuclear Information System (INIS)

    Wu, Ting; Feng, Xuhui; Carreon, Maria L.; Carreon, Moises A.

    2017-01-01

    Herein, we present the hydrothermal synthesis of SAPO-56 crystals with relatively controlled crystal/particle size. The effects of water content, aluminum source, gel composition, stirring, crystallization temperature and time, as well as the incorporation of crystal growth inhibitors during synthesis were systematically investigated. The synthesized SAPO-56 crystals displayed BET surface areas as high as ∼630 m"2 g"−"1 with relative narrow size distribution in the ∼5–60 μm range. Nitrogen BET surface areas in the 451 to 631 m"2 g"−"1 range were observed. Decreasing the crystallization temperature from 220 to 210 °C helped to decrease the average SAPO-56 crystal size. Diluted gel compositions promoted the formation of smaller crystals. Crystal growth inhibitors were found to be helpful in reducing crystal size and narrow the size distribution. Specifically, ∼5 μm SAPO-56 crystals displaying narrow size distribution were synthesized employing aluminum-tri-sec-butoxide as Al source, high water content, and high stirring rates.

  12. NONLINEAR OPTICAL MOLECULAR CRYSTAL BASED ON 2,6-DIAMINOPYRIDINE: SYNTHESIS AND CHARACTERIZATION

    Directory of Open Access Journals (Sweden)

    I. M. Pavlovetc

    2014-05-01

    Full Text Available The paper deals with investigation of a new nonlinear optical material based on nonlinear optical chromophore (4-Nitrophenol and aminopyridine (2,6-Diaminopyridine. Calculation results are presented for molecular packing in the crystalline compound, based on the given components. According to these results the finite material must have a noncentrosymmetric lattice, which determines the presence of the second order nonlinear optical response. Investigations carried out in this work confirm these calculations. Results of experiments are given describing the co-crystallization of these components and the following re-crystallization of the obtained material. In order to get a monocrystal form, the optimal conditions for the synthesis of molecular crystals based on these components are determined. Sufficiently large homogeneous crystals are obtained, that gave the possibility to record their spectra in the visible and near infrared parts of the spectrum, to determine their nonlinear optical properties and the level of homogeneity. Their optical (optical transmission and optical laser damage threshold and nonlinear optical properties are presented. For observation and measurement of the nonlinear optical properties an installation was built which implements the comparative method for measurements of nonlinear optical properties. A potassium titanyl oxide phosphate crystal was used as a sample for comparison. Results are given for the conversion efficiency of the primary laser radiation in the second optical harmonic relative to the signal obtained on the potassium titanyl oxide phosphate crystal. Obtained results show that the molecular co-crystal based on 2,6-Diaminopyridine is a promising nonlinear optical material for generating the second optical harmonic on the Nd: YAG laser (532 nm.

  13. SYNTHESIS, CHARACTERIZATION AND CRYSTAL STRUCTURE OF BIS-(2-HYDROXYBENZALDEHYDEDIAMINOGUANIZONE

    Directory of Open Access Journals (Sweden)

    Diana Dragancea, Vladimir B. Arion, Sergiu Shova

    2008-12-01

    Full Text Available The new ligand, bis(2-hydroxybenzaldehydediaminoguanizone (1 has been synthesized and characterized by elemental analysis, IR and 1H NMR spectroscopies. The crystal structure of the compound was determined by X-ray diffraction. The ligand C15H15N5O2·C2H5OH crystallizes in the monoclinic space group P21/c with unit cell parameters a = 8.9102(3, b = 10.0357(3, c = 19.7618(6 Å, β = 98.385(2°, Z = 4, V = 1748.21(9 Å3, R1 = 0.040. The amino form of the ligand adopts a planar conformation stabilized by two intramolecular hydrogen bonds of the type O–H···N, in which the H atoms of the central amino group are directed to the lone-pair regions of the azomethine nitrogen atoms.

  14. Synthesis, characterization and application of nanozeolite NaX from Vietnamese kaolin

    International Nuclear Information System (INIS)

    Ngoc, Don Ta; Pham, Thanh Huyen; Hong Nguyen, Khanh Dieu

    2013-01-01

    This paper presents the results of synthesis of nanozeolite NaX from Vietnamese kaolin. Influence factors on the control of crystal sizes and application of synthesized materials as adsorbent for organic compound are discussed. The results show that there are several factors that influence the synthesis. When water content in gel increases, crystal size of NaX increases sharply. The increase of alkaline and silica contents increases the crystallinity and decreases the particle size of nano NaX, and the particle size reaches the minimum at Na 2 O/Al 2 O 3 = 5.0 and SiO 2 /Al 2 O 3 = 4.0. Crystal sizes formed at low crystallizing temperature are smaller than those formed at higher temperature. Ageing time and crystallizing time strongly influence the crystallinity and crystal size, which is related to the number of crystal seeds formed during ageing period, the growth of seed and the partial solubility of crystal at maximum formation. Nano NaX was characterized by x-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Brunauer–Emmett–Teller (BET) adsorption, Fourier transform infrared (FTIR) and simultaneous thermogravimetry–differential scanning calorimetry (TG/DSC). At optimized synthesis conditions, nano NaX has surface area of 573 m 2 g −1 with external surface area of 92 m 2 g −1 , pore size distribution at 0.81 and 10.8 nm, average crystal size of 25 nm and thermal stability up to 789 °C. This material can adsorb cumene rapidly with high adsorption capacity and stability. (paper)

  15. Synthesis and Single Crystal Structures of Substituted-1,3-Selenazol-2-amines

    Directory of Open Access Journals (Sweden)

    Guoxiong Hua

    2016-12-01

    Full Text Available The synthesis and X-ray single crystal structures of a series of new 4-substituted-1,3-selenazol-2-amines is reported. The efficient preparation of these compounds was carried out by two-component cyclization of the selenoureas with equimolar amounts of α-haloketones. The selenoureas were obtained from the reaction of Woollins’ reagent with cyanamides, followed by hydrolysis with water. All new compounds have been characterized by IR spectroscopy, multi-NMR (1H, 13C, 77Se spectroscopy, accurate mass measurement and single crystal X-ray structure analysis.

  16. Synthesis and characterization of lithium fluoride nano crystals doped with silver

    International Nuclear Information System (INIS)

    Rosario M, B. R.; Ramirez C, G.; Encarnacion E, E. K.; Sosa A, M. A.

    2017-10-01

    Thermoluminescence (Tl) is the emission of light by certain materials to be heated below its incandescence temperature, having previously been exposed to an exciting agent such as ionizing radiation. Lithium fluoride (LiF) is the thermoluminescent material used in the manufacture of Tl-100 dosimeters. What morphological characteristics (size, crystallinity) do the nano crystals of pure lithium fluoride (LiF) have when doped with silver (Ag) by the precipitation method? The objective of this study was to synthesize and characterize the LiF nano crystals doped with silver (Ag) in concentrations of 0.02, 0.04, 0.06, 0.08, 0.1 and 0.2%. The samples were synthesized using as reagents; distilled water, ammonium fluoride (NH 4 F), lithium chloride (LiCl), silver nitrate (AgNO 3 ); and materials such as: 0.1 mg precision balance, spatulas, test piece, magnetic stirrer, beaker, volumetric flask, burette, burette clamp, key and magnetic stirring wand. In the characterization process we used and X-ray diffractometer (XRD) with which we obtained the X-ray diffraction spectrum with well-defined peaks that are characteristic of LiF. Using the Scherrer equation we calculate the sizes of nano crystals. This study demonstrates that is possible to synthesize LiF using new dopant materials. (Author)

  17. SYNTHESIS, CHARACTERIZATION AND CRYSTAL STRUCTURES ...

    African Journals Online (AJOL)

    B. S. Chandravanshi

    ABSTRACT. Reaction of [VO(acac)2] (acac = acetylacetonate) with ... Single crystal X-ray structural studies indicate that the hydrazone ligands coordinate to ..... Molecular structure of complex (1) at 30% probability displacement. Figure 4.

  18. SYNTHESIS, CHARACTERIZATION, AND CRYSTAL STRUCTURE ...

    African Journals Online (AJOL)

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    KEY WORDS: Barium, Crystal structure, 2,6-Pyridinedicarboxylic acid .... The rational design of novel metal-organic frameworks has attracted great ..... Bond, A.D.; Jones, W. Supramolecular Organization and Materials Design, Jones, W.; Rao,.

  19. Synthesis, characterization, crystal structures and DFT studies of some new 1,2,4-triazole and triazolidin derivatives

    Science.gov (United States)

    Abosadiya, Hamza M.; Anouar, El Hassane; Abusaadiya, Salima M.; Hasbullah, Siti Aishah; Yamin, Bohari M.

    2018-01-01

    A simple efficient method for synthesis of some new 1,2,4-Triazole and Triazolidin derivatives namely, 5-(4-methoxyphenyl)-2-phenyl-2,4-dihydro-3H-1,2,4-triazole-3-thione (1a), (2-chlorophenyl)(3,3-dimethyl-1-phenyl-5-thioxo-1,2,4-triazolidin-4-yl)methanone (1b) and (2-iodophenyl)(3,3-dimethyl-1-phenyl-5-thioxo-1,2,4-triazolidin-4-yl)methanone (1c) have been synthesized in high yields from the reaction of carbonoyl isothiocyanate with phenyl hydrazine. The final products were characterized by FT-IR, 1H and 13C NMR spectroscopic techniques. X-ray crystallographic studies showed that 1a crystallized in triclinic crystal system with space group Pī, while both 1b and 1c crystallized in orthorhombic crystal system with space group Pna21. The asymmetric unit of 1a consists two crystallographically independent molecules, while only one molecule in asymmetric unit for both 1b and 1c compounds. All molecules possess Csbnd H ….S intramolecular hydrogen bonds which formed a pseudo-six-membered ring. Experimental results have been confirmed by the state-of-art density functional theory (DFT) in gas and solvent phase by using five different hybrid functionals B3LYP, B3P86, CAM-B3LYP, M06-2X and PBE0 combined with 6-311++G(d, p) basis set. The experimental data are relatively well produced, and relatively good correlations are obtained between the predicted and experimental data.

  20. Synthesis and thermal characterization of CdS nano crystals in previously formed template of maleic anhydride-octene 1-vinyl butyl terpolymer

    International Nuclear Information System (INIS)

    Akbarov, O.H; Mammadova, R.E; Malikov, E.Y.

    2008-01-01

    Full text: Nano crystals have dimensions in the range 10100 nm. Crystals in this size range possess unique properties, which enable scientists to manufacture materials and devices capable of performing unimaginable tasks. For that reason synthesis of this semiconductor nano crystals is expedient. Many useful methods have been used for preparing sulphide semiconductor nano crystals, such as colloidal chemistry method, sol-gel method, inverse micelle method, in situ synthesis and assemble on polymer template. The most significant method is in situ synthesis and assemble of sulphide semiconductor nano crystals on polymer. Compared with other methods, the stability of nanoparticles is improved by the protection and confinement of the copolymer. Because of confinement and protection effects of template environmental risk is prevented in this method. On the base of this principles in situ synthesis of CdS nano crystals in maleic anhydride-octene 1-vinyl butyl terpolymer was realized in this scientific work. First of all in specific condition maleic anhydride, octene 1, and vinyl butyl ether were polymerized to form a terpolymer as the result of radical ter polymerization. In second step CdS nano crystals were synthesized in N,N-dimethylformamide solution of maleic anhydride-octene 1-vinyl butyl terpolymer through the reaction of thiourea with cadmium chloride. In this process CdCI 2 x 2.5H 2 O was dissolved in N,N-dimethylformamide solution of previously formed terpolymer and was heated in 90 0 C temperature for 4 hours with vigorous stirring. Then desired amount of thiourea in N,N-dimethylformamide was quickly injected into the reaction flask using a syringe. The reaction continued for another 1 hour, and a yellow clear solution was obtained, which indicated the formation of CdS nano crystals

  1. SYNTHESIS, CHARACTERIZATION AND CRYSTAL STRUCTURE ...

    African Journals Online (AJOL)

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    Reaction of [MoO2(acac)2] (where acac = acetylacetonate) with N'-(2-hydroxy-4- ... Single crystal X-ray structural studies indicate that the hydrazone ligand coordinates .... Molecular structure of the complex at 30% probability displacement.

  2. Synthesis and ultrastructure of plate-like apatite single crystals as a model for tooth enamel

    International Nuclear Information System (INIS)

    Zhuang, Zhi; Yoshimura, Hideyuki; Aizawa, Mamoru

    2013-01-01

    Hydroxyapatite (HAp) is an inorganic constituent compound of human bones and teeth, with superior biocompatibility and bioactivity characteristics. Its crystal structure is hexagonal, characterized by a(b)- and c-planes. In vertebrate long bones, HAp crystals have a c-axis orientation, while in tooth enamel, they have an a(b)-axis orientation. Many methods can be used to synthesize c-axis oriented HAp single crystals; however, to the best of our knowledge, there have been no reports on a synthesis method for a(b)-axis oriented HAp single crystals. In this study, we successfully synthesized plate-like HAp crystals at the air–liquid interface of a starting solution via an enzyme reaction of urea with urease. Crystal phase analysis and ultrastructure observations were carried out, and the results indicated that the particles were single crystals, with almost the same a(b)-axis orientation as tooth enamel. It is hoped that by utilizing their unique surface charge and atomic arrangement, the resulting particles can be used as a high-performance biomaterial, capable of adsorbing bio-related substances and a model for tooth enamel. - Highlights: ► Synthesis of plate-like hydroxyapatite crystals at air–liquid interface ► Ultrastructural analysis of plate-like hydroxyapatite crystals ► Plate-like hydroxyapatite single crystals with a high a(b)-axis orientation ► Plate-like hydroxyapatite single crystals as a model for tooth enamel

  3. Synthesis and ultrastructure of plate-like apatite single crystals as a model for tooth enamel

    Energy Technology Data Exchange (ETDEWEB)

    Zhuang, Zhi, E-mail: zhuang@meiji.ac.jp [Department of Applied Chemistry, School of Science and Technology, Meiji University, 1-1-1 Higashimita, Tama-ku, Kawasaki, Kanagawa 214-8571 (Japan); Yoshimura, Hideyuki, E-mail: hyoshi@isc.meiji.ac.jp [Department of Physics, School of Science and Technology, Meiji University, 1-1-1 Higashimita, Tama-ku, Kawasaki, Kanagawa 214-8571 (Japan); Aizawa, Mamoru, E-mail: mamorua@isc.meiji.ac.jp [Department of Applied Chemistry, School of Science and Technology, Meiji University, 1-1-1 Higashimita, Tama-ku, Kawasaki, Kanagawa 214-8571 (Japan)

    2013-07-01

    Hydroxyapatite (HAp) is an inorganic constituent compound of human bones and teeth, with superior biocompatibility and bioactivity characteristics. Its crystal structure is hexagonal, characterized by a(b)- and c-planes. In vertebrate long bones, HAp crystals have a c-axis orientation, while in tooth enamel, they have an a(b)-axis orientation. Many methods can be used to synthesize c-axis oriented HAp single crystals; however, to the best of our knowledge, there have been no reports on a synthesis method for a(b)-axis oriented HAp single crystals. In this study, we successfully synthesized plate-like HAp crystals at the air–liquid interface of a starting solution via an enzyme reaction of urea with urease. Crystal phase analysis and ultrastructure observations were carried out, and the results indicated that the particles were single crystals, with almost the same a(b)-axis orientation as tooth enamel. It is hoped that by utilizing their unique surface charge and atomic arrangement, the resulting particles can be used as a high-performance biomaterial, capable of adsorbing bio-related substances and a model for tooth enamel. - Highlights: ► Synthesis of plate-like hydroxyapatite crystals at air–liquid interface ► Ultrastructural analysis of plate-like hydroxyapatite crystals ► Plate-like hydroxyapatite single crystals with a high a(b)-axis orientation ► Plate-like hydroxyapatite single crystals as a model for tooth enamel.

  4. Controlled synthesis of thorium and uranium oxide nano-crystals

    International Nuclear Information System (INIS)

    Hudry, Damien; Apostolidis, Christos; Walter, Olaf; Gouder, Thomas; Courtois, Eglantine; Kubel, Christian; Meyer, Daniel

    2013-01-01

    Very little is known about the size and shape effects on the properties of actinide compounds. As a consequence, the controlled synthesis of well-defined actinide-based nano-crystals constitutes a fundamental step before studying their corresponding properties. In this paper, we report on the non-aqueous surfactant-assisted synthesis of thorium and uranium oxide nano-crystals. The final characteristics of thorium and uranium oxide nano-crystals can be easily tuned by controlling a few experimental parameters such as the nature of the actinide precursor and the composition of the organic system (e.g., the chemical nature of the surfactants and their relative concentrations). Additionally, the influence of these parameters on the outcome of the synthesis is highly dependent on the nature of the actinide element (thorium versus uranium). By using optimised experimental conditions, monodisperse isotropic uranium oxide nano-crystals with different sizes (4.5 and 10.7 nm) as well as branched nano-crystals (overall size ca. 5 nm), nano-dots (ca. 4 nm) and nano-rods (with ultra-small diameters of 1 nm) of thorium oxide were synthesised. (authors)

  5. Synthesis, characterization and crystal structure of 6-Chloro-4,4‧-dimethyl-2,2‧-bipyridine and 4,4‧-Dimethyl 2,2‧-bipyridine N-Oxide

    Science.gov (United States)

    Conterosito, Eleonora; Magistris, Claudio; Barolo, Claudia; Croce, Gianluca; Milanesio, Marco

    2016-03-01

    The synthesis, the NMR characterization and the crystal structure of 6-Chloro 4,4‧-dimethyl 2,2‧-bipyridine and of the reaction intermediate 4,4‧-Dimethyl 2,2‧-bipyridine N-Oxide are here reported. The target compound crystallizes in the orthorhombic system while the intermediate is monoclinic. In both structures, the molecules are linked by weak interactions. The structure of the reaction intermediate N-oxide is characterized by a dihedral angle between the two phenyl rings of 161.77° while the other is almost planar with a dihedral angle of 179.15°. The crystal packing was investigated, also with the aid of Hirshfeld surface analysis. In the N-oxide reaction intermediate the packing is governed by CH-O interactions, while in the product the packing is simply driven by minimizing the voids and thus maximizing the density, with a prevalence of H•••H and C•••H contacts, as indicated by fingerprint decomposition analysis.

  6. Synthesis of Fluorite (CaF2 Crystal from Gypsum Waste of Phosphoric Acid Factory in Silica Gel

    Directory of Open Access Journals (Sweden)

    Mohammad Misbah Khunur

    2012-06-01

    Full Text Available This paper report the synthesis and characterization of fluorite single crystal prepared from gypsum waste of phosphoric acid production in silica gel. Instead of its high calcium, gypsum was used to recycle the waste which was massively produces in the phosphoric acid production. The gypsum waste, the raw material of CaCl2 supernatant, was dissolved in concentrated HCl and then precipitated as calcium oxalate (CaC2O4 by addition of ammonium oxalate. The CaCl2 was obtained by dissolving the CaC2O4 with HCl 3M. The crystals were grown at room temperature in silica gel and characterized by AAS, FTIR and powder XRD. The optimum crystal growth condition, which is pH of gel, CaCl2 concentration and growth time, were investigated. The result shows that at optimum condition of pH 5.80, CaCl2 concentrations of 1.2 M, and growth time of 144 hours, colorless crystals with the longest size of 3 mm, were obtained (72.57%. Characterization of the synthesized crystal by AAS indicates that the obtained crystal has high purity. Meanwhile, analysis by FTIR spectra shows a Ca–F peak at 775 cm-1, and powder-XRD analysis confirms that the obtained crystal was fluorite (CaF2. © 2012 BCREC UNDIP. All rights reservedReceived: 11st April 2012; Revised: 4th June 2012; Accepted: 13rd June 2012[How to Cite: M.M. Khunur, A. Risdianto, S. Mutrofin, Y.P. Prananto. (2012. Synthesis of Fluorite (CaF2 Crystal from Gypsum Waste of Phosphoric Acid Factory in Silica Gel. Bulletin of Chemical Reaction Engineering & Catalysis, 7 (1: 71-77.  doi:10.9767/bcrec.7.1.3171.71-77 ][How to Link / DOI: http://dx.doi.org/10.9767/bcrec.7.1.3171.71-77 ] | View in 

  7. Single Crystal Synthesis and STM Studies of High Temperature Superconductors

    Science.gov (United States)

    Barrientos, Alfonso

    1997-01-01

    This is a final report for the work initiated in September of 1994 under the grant NAG8-1085 - NASA/OMU, on the fabrication of bulk and single crystal synthesis, specific heat measuring and STM studies of high temperature superconductors. Efforts were made to fabricate bulk and single crystals of mercury based superconducting material. A systematic thermal analysis on the precursors for the corresponding oxides and carbonates were carried out to synthesized bulk samples. Bulk material was used as seed in an attempt to grow single crystals by a two-step self flux process. On the other hand bulk samples were characterized by x-ray diffraction, electrical resistivity and magnetic susceptibility, We studied the specific heat behavior in the range from 80 to 300 K. Some preliminary attempts were made to study the atomic morphology of our samples. As part of our efforts we built an ac susceptibility apparatus for measuring the transition temperature of our sintered samples.

  8. SYNTHESIS, CRYSTAL STRUCTURE AND MAGNETIC ...

    African Journals Online (AJOL)

    Preferred Customer

    Much of the current effort on such extended hybrid metal organic complexes is ... In this paper, we report the synthesis, single crystal X-ray diffraction analysis and ..... with g = 2.0 (0.37 cm3 mol−1 K), and smoothly increases to a value of 0.45 ...

  9. Facile synthesis of gold nanomaterials with unusual crystal structures.

    Science.gov (United States)

    Fan, Zhanxi; Huang, Xiao; Chen, Ye; Huang, Wei; Zhang, Hua

    2017-11-01

    Gold (Au) nanomaterials have attracted wide research attention, owing to their high chemical stability, promising catalytic properties, excellent biocompatibility, unique electronic structure and outstanding localized surface plasmon resonance (LSPR) absorption properties; all of which are closely related to their size and shape. Recently, crystal-phase-controlled synthesis of noble metal nanomaterials has emerged as a promising strategy to tune their physicochemical properties. This protocol describes the detailed experimental procedures for the crystal-phase-controlled syntheses of Au nanomaterials with unusual crystal structures under mild conditions. Briefly, pure hexagonal close-packed (hcp) Au square sheets (AuSSs) with a thickness of ∼2.4 nm are synthesized using a graphene-oxide-assisted method in which HAuCl 4 is reduced by oleylamine in a mixture of hexane and ethanol. By using pure hexane as the solvent, well-dispersed ultrathin hcp/face-centered cubic (fcc) Au nanowires with a diameter of ∼1.6 nm on graphene oxide can be obtained. Meanwhile, hcp/fcc Au square-like plates with a side length of 200-400 nm are prepared via the secondary growth of Au on the hcp AuSSs. Remarkably, hexagonal (4H) Au nanoribbons with a thickness of 2.0-6.0 nm can be synthesized with a one-pot colloidal method in which HAuCl 4 is reduced by oleylamine in a mixed solvent of hexane and 1,2-dichloropropane. It takes 17-37 h for the synthesis of these Au nanomaterials with unusual crystal structures. Transmission electron microscopy (TEM) and atomic force microscopy (AFM) are used to characterize the resultant Au nanomaterials, which could have many promising applications, such as biosensing, near-IR photothermal therapy, catalysis and surface-enhanced Raman scattering (SERS).

  10. Nano crystals-Related Synthesis, Assembly, and Energy Applications

    International Nuclear Information System (INIS)

    Dai, Q.; Hu, M.Z.; Yu, B.Z.; William, W.; Seo, J.

    2011-01-01

    Fundamental material properties have been dramatically altered in the nano scale regime because of quantum confinement effect. The unique size-tunable functionalities of nano materials make them involved in an extensive variety of energy applications, such as light-emitting diodes and solar cells. These applications have been demonstrated to cut energy consumption. In response to the ever-growing energy demands as well as the concerns of global warming, researchers are actively placing their enormous emphasis on the exploration of energy savings. During this exploration, the primary stage requires the design of appropriate strategies for the synthesis of high-quality nano crystals in terms of size uniformity and superior optical/electronic properties. Especially, there is a need to seek green-chemistry approaches for the synthesis of environmentally benign and user-friendly nano crystals. Another recent area of focus is the use of individual nano crystals as building blocks for self-assembly, providing new opportunities to improve the nano crystal performance

  11. Synthesis of vaterite and aragonite crystals using biomolecules of tomato and capsicum

    Science.gov (United States)

    Chen, Long; Xu, Wang-Hua; Zhao, Ying-Guo; Kang, Yan; Liu, Shao-Hua; Zhang, Zai-Yong

    2012-12-01

    In this paper, biomimetic synthesis of calcium carbonate (CaCO3) in the presence of biomolecules of two vegetables-tomato and capsicum is investigated. Scanning electron microscopy and X-ray powder diffractometry were used to characterize the CaCO3 obtained. The biomolecules in the extracts of two vegetables are determined by UV-vis or FTIR. The results indicate that a mixture of calcite and vaterite spheres constructed from small particles is produced with the extract of tomato, while aragonite rods or ellipsoids are formed in the presence of extract of capsicum. The possible formation mechanism of the CaCO3 crystals with tomato biomolecules can be interpreted by particle-aggregation based non-classical crystallization laws. The proteins and/or other biomolecules in tomato and capsicum may control the formation of vaterite and aragonite crystals by adsorbing onto facets of them.

  12. Synthesis of a mixed-valent tin nitride and considerations of its possible crystal structures

    International Nuclear Information System (INIS)

    Caskey, Christopher M.; Holder, Aaron; Christensen, Steven T.; Biagioni, David; Ginley, David S.; Tumas, William; Perkins, John D.; Lany, Stephan; Zakutayev, Andriy; Shulda, Sarah; Diercks, David; Pylypenko, Svitlana; Richards, Ryan M.; Schwartz, Craig P.; Nordlund, Dennis; Kukliansky, Alon; Natan, Amir; Prendergast, David; Sun, Wenhao; Orvananos, Bernardo

    2016-01-01

    Recent advances in theoretical structure prediction methods and high-throughput computational techniques are revolutionizing experimental discovery of the thermodynamically stable inorganic materials. Metastable materials represent a new frontier for these studies, since even simple binary non-ground state compounds of common elements may be awaiting discovery. However, there are significant research challenges related to non-equilibrium thin film synthesis and crystal structure predictions, such as small strained crystals in the experimental samples and energy minimization based theoretical algorithms. Here, we report on experimental synthesis and characterization, as well as theoretical first-principles calculations of a previously unreported mixed-valent binary tin nitride. Thin film experiments indicate that this novel material is N-deficient SnN with tin in the mixed II/IV valence state and a small low-symmetry unit cell. Theoretical calculations suggest that the most likely crystal structure has the space group 2 (SG2) related to the distorted delafossite (SG166), which is nearly 0.1 eV/atom above the ground state SnN polymorph. This observation is rationalized by the structural similarity of the SnN distorted delafossite to the chemically related Sn 3 N 4 spinel compound, which provides a fresh scientific insight into the reasons for growth of polymorphs of metastable materials. In addition to reporting on the discovery of the simple binary SnN compound, this paper illustrates a possible way of combining a wide range of advanced characterization techniques with the first-principle property calculation methods, to elucidate the most likely crystal structure of the previously unreported metastable materials.

  13. Synthesis of a mixed-valent tin nitride and considerations of its possible crystal structures

    Energy Technology Data Exchange (ETDEWEB)

    Caskey, Christopher M. [National Renewable Energy Laboratory, Golden, Colorado 80401 (United States); Colorado School of Mines, Golden, Colorado 80401 (United States); Larix Chemical Science, Golden, Colorado 80401 (United States); Holder, Aaron; Christensen, Steven T.; Biagioni, David; Ginley, David S.; Tumas, William; Perkins, John D.; Lany, Stephan; Zakutayev, Andriy, E-mail: andriy.zakutayev@nrel.gov [National Renewable Energy Laboratory, Golden, Colorado 80401 (United States); Shulda, Sarah; Diercks, David; Pylypenko, Svitlana; Richards, Ryan M. [Colorado School of Mines, Golden, Colorado 80401 (United States); Schwartz, Craig P.; Nordlund, Dennis [SLAC National Accelerator Laboratory, Menlo Park, California 94025 (United States); Kukliansky, Alon; Natan, Amir [Tel Aviv University, Tel Aviv-Yafo (Israel); Prendergast, David; Sun, Wenhao [Lawrence Berkeley National Laboratory, Berkley, California 94720 (United States); Orvananos, Bernardo [Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); and others

    2016-04-14

    Recent advances in theoretical structure prediction methods and high-throughput computational techniques are revolutionizing experimental discovery of the thermodynamically stable inorganic materials. Metastable materials represent a new frontier for these studies, since even simple binary non-ground state compounds of common elements may be awaiting discovery. However, there are significant research challenges related to non-equilibrium thin film synthesis and crystal structure predictions, such as small strained crystals in the experimental samples and energy minimization based theoretical algorithms. Here, we report on experimental synthesis and characterization, as well as theoretical first-principles calculations of a previously unreported mixed-valent binary tin nitride. Thin film experiments indicate that this novel material is N-deficient SnN with tin in the mixed II/IV valence state and a small low-symmetry unit cell. Theoretical calculations suggest that the most likely crystal structure has the space group 2 (SG2) related to the distorted delafossite (SG166), which is nearly 0.1 eV/atom above the ground state SnN polymorph. This observation is rationalized by the structural similarity of the SnN distorted delafossite to the chemically related Sn{sub 3}N{sub 4} spinel compound, which provides a fresh scientific insight into the reasons for growth of polymorphs of metastable materials. In addition to reporting on the discovery of the simple binary SnN compound, this paper illustrates a possible way of combining a wide range of advanced characterization techniques with the first-principle property calculation methods, to elucidate the most likely crystal structure of the previously unreported metastable materials.

  14. Synthesis and characterization of p-type boron-doped IIb diamond large single crystals

    International Nuclear Information System (INIS)

    Li Shang-Sheng; Li Xiao-Lei; Su Tai-Chao; Jia Xiao-Peng; Ma Hong-An; Huang Guo-Feng; Li Yong

    2011-01-01

    High-quality p-type boron-doped IIb diamond large single crystals are successfully synthesized by the temperature gradient method in a china-type cubic anvil high-pressure apparatus at about 5.5 GPa and 1600 K. The morphologies and surface textures of the synthetic diamond crystals with different boron additive quantities are characterized by using an optical microscope and a scanning electron microscope respectively. The impurities of nitrogen and boron in diamonds are detected by micro Fourier transform infrared technique. The electrical properties including resistivities, Hall coefficients, Hall mobilities and carrier densities of the synthesized samples are measured by a four-point probe and the Hall effect method. The results show that large p-type boron-doped diamond single crystals with few nitrogen impurities have been synthesized. With the increase of quantity of additive boron, some high-index crystal faces such as {113} gradually disappear, and some stripes and triangle pits occur on the crystal surface. This work is helpful for the further research and application of boron-doped semiconductor diamond. (cross-disciplinary physics and related areas of science and technology)

  15. Synthesis, Crystal Structural Characterization and Biological Properties of Thiosemicarbazones of Schiff Bases Derived from 4-Acyl-2-pyrazoline-5-one

    Directory of Open Access Journals (Sweden)

    Arjunsinh Rana

    2011-01-01

    Full Text Available A novel synthesis, single crystal and biological activity of 4-acylthiosemicarbazone-3-methyl-1-(4`-methylphenyl-2-pyrazolin-5-one by condensation of 4-acyl-3-methyl-1-(4`-methylphenyl-2-pyrazolin-5-one with thiosemicarbazide was carried out. The compounds were characterized on the basis of elemental analysis, IR, 1H NMR, Mass, DSC and 13C NMR spectral data. The compounds were tested for their antibacterial activity against various gram +ve and -ve bacteria. The results were compared with the marketed drugs. The crystal structure was determined by single x-ray diffraction. 4-Acetyl thiosemicarbazone-3-methyl-1-(4`-methylphenyl-2-pyrazolin-5-one(AcPTMP-ths crystallizes in the monoclinic system, space group P21/n with a=6.0828(7Å, b=29.547(4Å, c=7.9101(15Å, α=90°, γ=95.602(15°, γ=90°, V=1414.9(4 Å3, Z=4, Dc=1.429 mg/m3 and 4-Propionylthiosemicarbazone-3-methyl-1-(4`-methylphenyl-2-pyrazolin-5-one (PropPTMP-ths crystallizes in the monoclinic system, space group P21/c with a=13.5622(10Å, b=13.3671(12Å, c=22.151(2Å, α=90°, β=93.13(7°, γ=90°, V=4010.1(6 Å3, Z=8, Dc=1.310 mg/m3. The compounds were screened for antibacterial properties and exhibited potential activity.

  16. Ionothermal synthesis, crystal structure, and magnetic study of Co2PO4OH isostructural with caminite.

    Science.gov (United States)

    Wang, Guangmei; Valldor, Martin; Spielberg, Eike T; Mudring, Anja-Verena

    2014-03-17

    A new framework cobalt(II) hydroxyl phosphate, Co2PO4OH, was prepared by ionothermal synthesis using 1-butyl-4-methyl-pyridinium hexafluorophosphate as the ionic liquid. As the formation of Co2PO4F competes in the synthesis, the synthesis conditions have to be judiciously chosen to obtain well-crystallized, single phase Co2PO4OH. Single-crystal X-ray diffraction analyses reveal Co2PO4OH crystallizes with space group I41/amd (a = b = 5.2713(7) Å, c = 12.907(3) Å, V = 358.63(10) Å(3), and Z = 4). Astonishingly, it does not crystallize isotypically with Co2PO4F but rather isotypically with the hydroxyl minerals caminite Mg1.33[SO4(OH)0.66(H2O)0.33] and lipscombite Fe(2–y)PO4(OH) (0 ≤ y ≤ 2/3). Phosphate tetrahedra groups interconnect four rod-packed face-sharing ∞(1){CoO(6/2)} octahedra chains to form a three-dimensional framework structure. The compound Co2PO4OH was further characterized by powder X-ray diffraction, Fourier transform–infrared, and ultraviolet–visible spectroscopy, confirming the discussed structure. The magnetic measurement reveals that Co2PO4OH undergoes a magnetic transition and presents at low temperatures a canted antiferromagnetic spin order in the ground state.

  17. Synthesis and characterization of KY3F10 and KY3F10:Yb:Nd:Tm crystals for optical applications

    International Nuclear Information System (INIS)

    Linhares, Horacio Marconi da Silva Dantas

    2009-01-01

    In this work, crystals of KY 3 F 10 pure and doped with Yb, Nd and Tm were grown aiming at the attainment of blue emission via Tm 3+ ions up conversion. It was established the best conditions to synthesis and purification of KY 3 F 10 . Crystals doped with 1.3 mol% Nd, 0.5 mol% Tm and some concentrations of Yb (5, 10, 20, 30 and 40 mol%) were obtained by slow cooling of the charge from the melt, using an usual conventional synthesis system and in a reactive HF atmosphere. It was taken into account parameters as cooling rate and different configurations of boats to conditioning the materials. The limit of Yb concentration to obtain a unique cubic phase was determined as 30mol%, for the cooling rates used in this work. The physical and chemical characterizations of the samples were performed by X-ray diffraction, differential thermal analysis, inductively coupled plasma-optical emission spectroscopy (ICP-OES), scanning electron microscopy, optical absorption and emission. An initial spectroscopic study was performed to verify the effect of the Yb 3+ concentration regarding the blue emission efficiency in the KY 3 F 10 :Yb:Nd:Tm. When the Nd 3+ is pumped at 797 nm, it was determined that the suitable Yb concentrations are between 10 and 20 mol% to obtain blue emission at 480 nm, and between 20 and 30 mol% to obtain emission at 450 nm. It was observed that two emissions bands in the UV (350 and 360nm) enhanced proportionally with the Yb 3+ concentration. (author)

  18. Synthesis and characterization of Al-TON zeolite using a dialkylimizadolium as structure-directing agent

    Energy Technology Data Exchange (ETDEWEB)

    Lopes, Christian Wittee; Pergher, Sibele Berenice Castella, E-mail: chriswittee@gmail.com [Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN (Brazil); Villarroel-Rocha, Jhonny [Laboratorio de Solidos Porosos, Instituto de Fisica Aplicada, Universidad Nacional de San Luis, Chacabuco, San Luis (Argentina); Silva, Bernardo Araldi Da; Mignoni, Marcelo Luis [Universidade Regional Integrada, Erechim, RS (Brazil)

    2016-11-15

    In this work, the synthesis of zeolites using 1-butyl-3-methylimidazolium chloride [C{sub 4}MI]Cl as a structure-directing agent was investigated. The organic cation shows effectiveness and selectivity for the syntheses of TON zeolites under different reaction conditions compared to the traditional structure directing agent, 1,8-diaminooctane. The 1-butyl-3-methylimidazolium cation lead to highly crystalline materials and its role as OSDA in our synthesis conditions has been confirmed by characterization techniques. ICP-OES confirms the presence of Al in the samples and {sup 27}Al MAS NMR analysis indicated that aluminum atoms were incorporated in tetrahedral coordination. Scanning electron microscopy indicated that changing the crystallization condition (static or stirring), zeolites with different crystal size were obtained, which consequently affects the textural properties of the zeolites. Moreover, varying some synthesis parameters MFI zeolite can also be obtained. (author)

  19. Synthesis, characterization, and reactivity of furan- and thiophene-functionalized bis(n-heterocyclic carbene) complexes of iron(II)

    KAUST Repository

    Rieb, Julia; Raba, Andreas; Haslinger, Stefan; Kaspar, Manuel; Pö thig, Alexander; Cokoja, Mirza; Basset, Jean-Marie; Kü hn, Fritz

    2014-01-01

    The synthesis of iron(II) complexes bearing new heteroatom-functionalized methylene-bridged bis(N-heterocyclic carbene) ligands is reported. All complexes are characterized by single-crystal X-ray diffraction (SC-XRD), nuclear magnetic resonance

  20. Advantage of low-temperature hydrothermal synthesis to grow stoichiometric crednerite crystals

    Science.gov (United States)

    Poienar, Maria; Martin, Christine; Lebedev, Oleg I.; Maignan, Antoine

    2018-06-01

    This work reports a new approach for the growth of stoichiometric crednerite CuMnO2 crystals. The hydrothermal reaction, starting from soluble metal sulphates as precursors, is assisted by ethylene glycol and the formation of crednerite is found to depend strongly on pH and temperature. This method allows obtaining small hexagonal platelets with the larger dimension about 1.0-1.5 μm and with a composition characterized by a Cu/Mn ratio of 1. Thus, these crystals differ from the needle-like millimetric ones obtained by the flux technique for which the composition departs from the expected one and is close to Cu1.04Mn0.96. This monitoring of the cationic composition in crednerite, using hydrothermal synthesis, is important as the Cu/Mn ratio controls the low temperature antiferromagnetic ground-state.

  1. Synthesis, crystal growth, characterization and theoretical studies of 4-aminobenzophenonium picrate

    Science.gov (United States)

    Aditya Prasad, A.; Muthu, K.; Rajasekar, M.; Meenatchi, V.; Meenakshisundaram, S. P.

    2015-01-01

    Single crystals of 4-aminobenzophenonium picrate (4ABPP) were grown by slow evaporation of a mixed solvent system methanol-acetone (1:1,v/v) containing equimolar quantities of picric acid and 4-aminobenzophenone. The proton and carbon signals are confirmed by nuclear magnetic resonance spectroscopy. The various functional groups present in the molecule are identified by FT-IR analysis. Optimized geometry, first-order molecular hyperpolarizability (β), polarizability (α), bond length, bond angles and excited state energy from theoretical UV were derived by Hartree-Fock calculations. The complete assignment of the vibrational modes for 4-aminobenzophenonium picrate was performed by the scaled quantum mechanics force field (SQMFF) methodology using potential energy distribution. Natural bond orbital (NBO) calculations were employed to study the stabilities arising from charge delocalization and intermolecular interactions of 4ABPP. The atomic charge distributions of the various atoms present in 4ABPP are obtained by Mulliken charge population analysis. The as-grown crystal is further characterized by thermal and optical absorbance studies.

  2. The synthesis, characterization, crystal structure and theoretical calculations of a new meso-BOBIPY substituted phthalonitrile

    International Nuclear Information System (INIS)

    Sen, Pinar; Yildiz, S. Zeki; Atalay, Yusuf; Dege, Necmi; Demirtas, Günes

    2014-01-01

    A novel 4-(2-meso-BOBIPY-phenoxy)phthalonitrile (6) derivative has been synthesized starting from BF 3 –OEt 2 complex and 4-(2-meso-dipyrromethene-phenoxy)phthalonitrile (5) which was prepared by the oxidation of 4-(2-meso-dipyrromethane-phenoxy)phthalonitrile (4). The final product exhibit noticeable spectroscopic properties which were examined by its absorption and fluorescence emission spectra. The original compounds prepared in the reaction pathway were characterized by the combination of FT-IR, 1 H and 13 C NMR, UV–vis, MS and HRMS spectral data. The final product (6) was obtained as single crystal which crystallized in the triclinic space group P-1 with a=7.9411 (6) Å, b=9.0150 (6) Å, c=14.419 (1) Å, α=74.917 (5)°, β=86.824 (6)°, γ=84.109 (5)° and Z=2. The crystal structure has intermolecular C–H···F–B and C–H···N interactions. These interactions construct bifurcated hydrogen bonds in the crystal structure. In this study, It has been calculated; molecular structure, vibrational frequencies, 1 H and 13 C NMR chemical shifts and HOMO and LUMO energies of the title compound by using B3LYP method with 6–311++G(dp) basis set, and the electronic spectral characterization was investigated for the target product, as well. - Highlights: • A novel 4-(2-meso-BOBIPY-phenoxy)phthalonitrile derivative has been synthesized. • The title product exhibit noticeable spectroscopic properties which were examined by its absorption and fluorescence emission spectra. • The final product (6) was obtained as single crystal which crystallized in the triclinic space group. • Molecular structure, vibrational frequencies, 1 H and 13 C NMR chemical shifts and HOMO and LUMO energies of the title compound were calculated theoretically. • The electronic spectral characterization was investigated, as well. • The title compound is also open to prepare further BODIPY substituted oligomeric molecules via on it

  3. Synthesis and characterization of gel-grown cobalt tartrate crystals

    Indian Academy of Sciences (India)

    ... in electronics, optics and industries. A series of pure and mixed crystals ... bility method. A few researchers reported the growth of crystals of strontium tartrate ... grow it by chemical reaction method using the gel technique. The crystallization ...

  4. A facile soft template synthesis and characterization of PbHAsO4 nanocrystals

    International Nuclear Information System (INIS)

    Xiu Zhiliang; Lue Mengkai; Zhou Guangjun; Gu Feng; Zhang Haiping; Xu Dong; Yuan Duorong

    2004-01-01

    Monoclinic lead hydrogen arsenate (LHA) nanocrystals with different crystallization morphologies and crystallite sizes were prepared successfully by a soft template synthesis method in the presence of sodium dodecylbenzenesulfonate (SDBS) or polyvinylpyrrolidone (PVP). The products were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The possible mechanism of SDBS and PVP in the experiment was briefly illustrated

  5. Synthesis and characterization of boehmites obtained from gibbsite in presence of different environments

    Energy Technology Data Exchange (ETDEWEB)

    Denigres Filho, Ricardo Wilson Nastari; Rocha, Gisele de Araujo; Vieira-Coelho, Antonio Carlos, E-mail: acvcoelh@usp.br [Universidade de Sao Paulo (LPSS/EP/USP), SP (Brazil). Departamento de Engenharia Metalurgica e de Materiais. Laboratorio de Materias-Primas Particuladas; Montes, Celia Regina [Centro de Energia Nuclear na Agricultura (NUPEGEL/CENA/USP), Piracicaba, SP (Brazil). Nucleo de Pesquisas Geoquimicas e Geofisicas da Listosfera

    2016-05-15

    In this study, results related to boehmite synthesis by hydrothermal processes starting from a Bayer commercial gibbsite are reported. The processes have been conducted from aqueous suspensions with initial acidic or alkaline pH, without or with acetate ion, at 160 deg C for 72h to 168h. The final materials were characterized by X-ray diffraction (XRD), thermal methods (DTA and TGA) and scanning electron microscopy (SEM). The influence of the synthesis conditions on the morphology of the boehmite crystals obtained from the gibbsite at different hydrothermal processes are discussed. (author)

  6. Ultrafast Hydro-Micromechanical Synthesis of Calcium Zincate: Structural and Morphological Characterizations

    Directory of Open Access Journals (Sweden)

    Vincent Caldeira

    2017-01-01

    Full Text Available Calcium zincate is a compound with a large panel of application: mainly known as an advantageous replacement of zinc oxide in negative electrodes for air-zinc or nickel-zinc batteries, it is also used as precursor catalyst in biodiesel synthesis and as antifungal compound for the protection of limestone monuments. However, its synthesis is not optimized yet. In this study, it was elaborated using an ultrafast synthesis protocol: Hydro-Micromechanical Synthesis. Two other synthesis methods, Hydrochemical Synthesis and Hydrothermal Synthesis, were used for comparison. In all cases, the as-synthesized samples were analyzed by X-ray diffraction, scanning electron microscopy, and LASER diffraction particle size analysis. Rietveld method was used to refine various structural parameters and obtain an average crystallite size, on a Hydro-Micromechanical submicronic sample. X-ray single crystal structure determination was performed on a crystal obtained by Hydrochemical Synthesis. It has been shown that regardless of the synthesis protocol, the prepared samples always crystallize in the same crystal lattice, with P21/c space group and only differ from their macroscopic textural parameters. Nevertheless, only the Hydro-Micromechanical method is industrially scalable and enables a precise control of the textural parameters of the obtained calcium zincate.

  7. Synthesis and thermoluminescent characterization of LiF doped with Ag; Sintesis y caracterizacion termoluminiscente de LiF dopado con Ag

    Energy Technology Data Exchange (ETDEWEB)

    Encarnacion, E. K.; Reyes, J.; Guerrero, Z. [Universidad Autonoma de Santo Domingo, Facultad de Ciencias, Ciudad Universitaria, Santo Domingo (Dominican Republic); Sosa, M. A.; Vallejo, M. A.; Rivera P, E., E-mail: emma.kee@gmail.com [Universidad de Guanajuato, Campus Leon, Division de Ciencias e Ingenierias, Loma del Bosque 103, Col. Lomas del Campestre, 37150 Leon, Guanajuato (Mexico)

    2015-10-15

    Full text: In this paper the synthesis and characterization of lithium fluoride (LiF) crystals pure and activated with silver (Ag) is reported. The synthesis was carried out by the method of co-precipitation; three samples were obtained one of pure LiF and two were activated with 0.02 and 0.04% of Ag. All samples were subjected to X-ray emission and the results were analyzed. The synthesized samples were characterized by X-ray diffraction, thermoluminescence and X-ray fluorescence. The XRD results show complete crystal structures. The radiation dosimetry responses are discussed. These are the first results of a research conducted at the Universidad Autonoma de Santo Domingo in collaboration with the Universidad de Guanajuato. (Author)

  8. Purification, characterization and crystallization of the F-ATPase from Paracoccus denitrificans.

    Science.gov (United States)

    Morales-Rios, Edgar; Watt, Ian N; Zhang, Qifeng; Ding, Shujing; Fearnley, Ian M; Montgomery, Martin G; Wakelam, Michael J O; Walker, John E

    2015-09-01

    The structures of F-ATPases have been determined predominantly with mitochondrial enzymes, but hitherto no F-ATPase has been crystallized intact. A high-resolution model of the bovine enzyme built up from separate sub-structures determined by X-ray crystallography contains about 85% of the entire complex, but it lacks a crucial region that provides a transmembrane proton pathway involved in the generation of the rotary mechanism that drives the synthesis of ATP. Here the isolation, characterization and crystallization of an integral F-ATPase complex from the α-proteobacterium Paracoccus denitrificans are described. Unlike many eubacterial F-ATPases, which can both synthesize and hydrolyse ATP, the P. denitrificans enzyme can only carry out the synthetic reaction. The mechanism of inhibition of its ATP hydrolytic activity involves a ζ inhibitor protein, which binds to the catalytic F₁-domain of the enzyme. The complex that has been crystallized, and the crystals themselves, contain the nine core proteins of the complete F-ATPase complex plus the ζ inhibitor protein. The formation of crystals depends upon the presence of bound bacterial cardiolipin and phospholipid molecules; when they were removed, the complex failed to crystallize. The experiments open the way to an atomic structure of an F-ATPase complex. © 2015 The Authors.

  9. Synthesis and characterization of five-coordinated indium amidinates

    Energy Technology Data Exchange (ETDEWEB)

    Riahi, Yasaman

    2016-07-29

    The focus of this work is synthesis, characterization and exploring the reactivity of new indium amidinate compounds of the type R{sub 2}InX (R = R''NCR'NR''; R' = Ph, R'' = SiMe{sub 3}, iPr, dipp; X = Br, Cl) with the coordination number of five and R{sub 3}In (R = Me{sub 3}SiNCPhNSiMe{sub 3}) with the coordination number of six. By using amidinates as chelating ligands the electron deficiency of indium atom will be resolved. Additionally, by using different substituents the study of the different synthesized indium amidinates has become possible. The selected method for the synthesis allows the carbodiimides to react with organolithium compounds to get the corresponding lithium amidinates. Afterwards the resulting lithium amidinates take part in transmetalation reactions with InBr{sub 3} and InCl{sub 3}. The study of the reactivity of indium amidinate complexes including nucleophilic reactions as well as their reduction were also examined. Beside crystal structure analysis, nuclear magnetic resonance spectroscopy as well as elemental analysis has been applied to characterize the compounds.

  10. Synthesis and Characterization of Magnesium Substituted Aluminophosphate Molecular Sieves with AEL Structure

    Institute of Scientific and Technical Information of China (English)

    Benjing Xu; Ling Qian; Xinmei Liu; Chunmin Song; Zifeng Yan

    2004-01-01

    MAPO-11 molecular sieves were synthesized by hydrothermal methods. The influence of precursor of magnesium, Mg/Al ratio, synthesis temperature, synthesis time and the type of template on the formation and properties of MAPO-11 molecular sieves was examined. The samples were characterized by the techniques of X-ray diffraction (XRD), scanning electron microscopy (SEM), thermogravimetric/differential thermogravimetric analysis (TG-DGA), etc. The results show that the shape and size of crystal were influenced by the precursor of Mg, the Mg/Al ratio and the type of template, and the TG-DGA analysis shows that MAPO-11 molecular sieves as-synthesized have poor thermal stability.

  11. Synthesis and single crystal X-ray analysis of two griseofulvin metabolites

    DEFF Research Database (Denmark)

    Rønnest, Mads Holger; Harris, Pernille; Gotfredsen, Charlotte Held

    2010-01-01

    The two phenols, 6-O-desmethyl griseofulvin and 4-O-desmethyl griseofulvin are metabolites of the antifungal drug griseofulvin. Herein, we present an improved synthesis of the 6-phenol derivative, and an unequivocal proof of both structures by single-crystal X-ray analysis.......The two phenols, 6-O-desmethyl griseofulvin and 4-O-desmethyl griseofulvin are metabolites of the antifungal drug griseofulvin. Herein, we present an improved synthesis of the 6-phenol derivative, and an unequivocal proof of both structures by single-crystal X-ray analysis....

  12. Synthesis and Characterization of Photo-Responsive Thermotropic Liquid Crystals Based on Azobenzene

    Directory of Open Access Journals (Sweden)

    Runmiao Yang

    2018-03-01

    Full Text Available A series of new thermotropic liquid crystals (LCs containing azobenzene units was synthesized. The structures of the compounds were characterized by means of NMR and FTIR spectroscopy. Their mesomorphic behaviors were investigated via differential scanning calorimetry (DSC and polarizing optical microscopy (POM. Based on the POM and DSC measurements, the optical properties of the Razo-ester were tested using UV-vis spectroscopy. The azobenzene side chain displayed a strong ability to influence the formation of thermotropic LCs.

  13. Synthesis and characterization of liquid crystals and their thermoset films

    International Nuclear Information System (INIS)

    Ahn, Yong-Ho; Jung, Myung-Sup; Chang, Jin-Hae

    2010-01-01

    We prepared a series of aromatic liquid crystals (LCs) based on aromatic ester units with the reactive end groups methyl-maleimide and nadimide, and the resulting LCs were thermally cross-linked to produce liquid crystalline thermoset (LCT) films by means of solution-casting and heat treatment. The synthesized LCs and LCTs were characterized with Fourier transform infrared (FT-IR) spectroscopy, 1 H nuclear magnetic resonance (NMR), differential scanning calorimetry (DSC), thermomechanical analysis (TMA), and polarizing optical microscopy with a hot stage. We found that all these LCs form nematic phases. The coefficients of thermal expansion (CTEs) of the LCT films are strongly affected by the reactive end group and the mesogen units in their main-chain structures. The methyl-maleimide-terminated biphenyl LCT was found to have the lowest CTE.

  14. Synthesis, characterization and crystal structure of N,N'-Bis(2,3-Dimethoxybenzylidene)-1,2-Diaminoethane

    Czech Academy of Sciences Publication Activity Database

    Khalaji, A.D.; Fejfarová, Karla; Dušek, Michal; Bijanzadeh, H.R.

    2011-01-01

    Roč. 41, č. 12 (2011), 1955-1960 ISSN 1074-1542 Institutional research plan: CEZ:AV0Z10100521 Keywords : Shiff bases * X-ray diffraction * Jana2006 * crystal structure * characterization Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 0.566, year: 2011

  15. Large-scale synthesis and growth habit of 3-D flower-like crystal of PbTe

    Science.gov (United States)

    Zhou, Nan; Chen, Gang; Yang, Xi; Zhang, Xiaosong

    2012-02-01

    In this paper, 3-D flower-like crystal of PbTe was successfully synthesized using Pb(CH3COO)2·3H2O and Na2TeO3 as precursors under hydrothermal conditions, and characterized by means of scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray diffraction pattern (XRD). The reaction parameters that influenced the evolution of PbTe synthesis and morphology were investigated. It was shown that the flower-like crystal of PbTe was composed of a nucleus with eight pods. A possible growth mechanism was proposed based on the calculation of the surface energies of PbTe and the SEM observation. Furthermore, the temperature-dependent transport properties of 3-D flower-like crystal of PbTe specimen have been evaluated with an average thermoelectric power of 120 S cm-1 and electrical conductivity of 220 μV K-1 at 740 K.

  16. Synthesis and crystal structure of the quaternary compound AgFe{sub 2}GaTe{sub 4}

    Energy Technology Data Exchange (ETDEWEB)

    Delgado, Gerzon E., E-mail: gerzon@ula.ve [Laboratorio de Cristalografía, Departamento de Química, Facultad de Ciencias, Universidad de Los Andes, Mérida 5101 (Venezuela, Bolivarian Republic of); Quintero, Eugenio; Tovar, Rafael; Grima-Gallardo, Pedro; Quintero, Miguel [Centro de Estudio de Semiconductores, Departamento de Física, Facultad de Ciencias, Universidad de Los Andes, Mérida 5101 (Venezuela, Bolivarian Republic of)

    2014-11-15

    Highlights: • New quaternary compound. • Synthesis from solid state reaction. • Crystal structure. • Rietveld refinement. - Abstract: The crystal structure of the quaternary compound AgFe{sub 2}GaTe{sub 4}, belonging to the system I–II{sub 2}–III–VI{sub 4}, was characterized by Rietveld refinement using X-ray powder diffraction data. The powder pattern was composed by 84.5% of the principal phase AgFe{sub 2}GaTe{sub 4} and 15.5% of the secondary phase FeTe. This material crystallizes with stannite structure in the tetragonal space group I-42m (N° 121), Z = 2, unit cell parameters a = 6.3409(2) Å, c = 12.0233(4) Å, V = 483.42(3) Å{sup 3}, and is isostructural with CuFe{sub 2}InSe{sub 4}.

  17. Synthesis, crystal structure, characterizations and magnetic study of a novel two-dimensional iron fluoride

    Science.gov (United States)

    Bouketaya, Sabrine; Smida, Mouna; Abdelbaky, Mohammed S. M.; Dammak, Mohamed; García-Granda, Santiago

    2018-06-01

    A new hybrid compound formulated as [Fe3F8(H2O)2](Am2TAZ)2 (Am2TAZ= 3,5-diamino-1,2,4-triazole) was prepared under hydrothermal conditions. The crystal structure was solved by single-crystal X-ray diffraction and the bulk was characterized by thermal analyses (TG-MS), vibrational spectroscopy (FTIR, Raman), Ultraviolet-visible spectroscopy (UV-Vis), and scanning electron microscopy (SEM-EDX). It crystallizes in the triclinic system space group P 1 ̅ with unit cell parameters a= 7.100(2) Å, b= 7.658(2) Å, c= 8.321(2) Å, α = 107.330(20)°, β = 111.842(18)°, γ = 93.049(17)°, Z = 1 and V= 394.01(17) Å3. The studied X-ray crystal structure shows the two oxidation states for iron atoms (Fe2+, Fe3+) and generates a 2D inorganic network, built up of inorganic layers constructed from infinite inorganic chains running along a axis. In fact, these chains are connected via (Fe3+(3)F6) octahedral. OW-H…F and N-H…F hydrogen bonds, making up the whole 3D network, are strongly linked in the layers. Magnetization measurements were performed, exhibiting the paramagnetic feature of the studied compound above 150 K.

  18. Synthesis, characterization and crystal structure of a ...

    African Journals Online (AJOL)

    The Mo atom in the complex is in octahedral coordination. Thermal stability of the complex has also been studied. KEY WORDS: Molybdenum complex, Hydrazone ligand, Crystal structure, X-ray diffraction, Thermal property. Bull. Chem. Soc. Ethiop. 2014, 28(3), 409-414. DOI: http://dx.doi.org/10.4314/bcse.v28i3.10 ...

  19. Utilization of Snail (Achatina fulica Shell Waste for Synthesis of Calcium Tartrate Tetrahydrate (CaC4H4O6.4H2O Single Crystals in Silica Gel

    Directory of Open Access Journals (Sweden)

    Imam Sakdi

    2012-01-01

    Full Text Available Snail (Achatina fulica shell waste is massively produced by many home industries in Indonesia, especially in East Java. The snail shell is known for high calcium; therefore it is potential to be used as calcium source of supernatant in the synthesis of piezoeletric material, such as single crystal of calcium tartrate tetrahydrate (CaTT. The aim of this research is to study the synthesis and characterization of CaTT or CaC4H4O6.4H2O from snail shell waste in silica gel. Supernatant solution of CaCl2 was prepared from CaO, which previously made by calcinating the shell at 1000°C, and then reacted with HCl 1,5M. Synthesis of CaTT was conducted in a single-tube reaction at room temperature in which silica gel was used as growth medium with gelling time of 10 days and growth time of 2 weeks. The pH of gel and CaCl2 concentration were varied, 3.00; 3.50; 4.00; 4.50; 5.00; and 0.27; 0.36; 0.45; 0.54 M respectively, in order to obtain optimum condition of the synthesis, which is indicated from crystal yields. The synthesized crystals were characterized by atomic adsorption spectrophotometry (AAS, infrared spectroscopy (IR and powder X-ray diffraction (XRD. Experimental data shows that optimum condition was obtained at pH of 3.50 and [CaCl2] of 0.45M with yield of 69.37%. The obtained single crystal has clear color and octahedral-like shape with size ranged between 4 – 9 mm. Analysis data by FTIR and powder XRD confirmed that the obtained crystal was CaTT single crystals with crystal system of orthorhombic.

  20. Synthesis and characterization of M-type barium hexferrite by ultrasonic inter-dispersion of chemical precipitate

    International Nuclear Information System (INIS)

    Garcia Junior, E.S.; Gomes Junior, G.G.; Ogasawara, T.

    2010-01-01

    This work is concerned with the study the synthesis and characterization of M-type barium hexaferrite powder by chemical precipitation type and ultrasonic interdispersion of precursor materials Fe(OH) 3 and Ba(OH) 2 ,separately and ultrasonic inter-dispersion, followed by drying and calcining. In order to guide the experimental work was carried out a preliminary thermodynamic analysis of the system Ba-Fe-H 2 O at 25 deg C. The study shows that the phase formation of M-type barium hexaferrite is obtained at a calcination at 1000 deg C, characterized by X-ray diffraction, the grain growth of the final product of synthesis depending on the calcination temperature is visible by SEM. The synthesis method developed in this research is an option to achieve the results that would be obtained if the co-precipitation of ferric and barium hydroxide was thermodynamically possible, where you can get crystallization of barium hexaferrite in a calcination at 1000 deg C. (author)

  1. A facile approach towards synthesis, characterization, single crystal structure, and DFT study of 5-bromosalicylalcohol

    Energy Technology Data Exchange (ETDEWEB)

    Rastogi, Rupali, E-mail: rastogirupali@ymail.com [ITM University, Department of Chemistry (India); Tarannum, Nazia [Ch. Charan Singh University, Department of Chemistry (India); Butcher, R. J. [Howard University, Chemistry Department (United States)

    2016-03-15

    5-Bromosalicylalcohol was prepared by the interaction of NaBH{sub 4} and 5-bromosalicylaldehyde. The use of sodium borohydride makes the reaction easy, facile, economic and does not require any toxic catalyst. The compound is characterized by FTIR, {sup 1}H NMR, {sup 13}C NMR, TEM and ESI-mass spectra. Crystal structure is determined by single crystal X-ray analysis. Quantum mechanical calculations of geometries, energies and thermodynamic parameters are carried out using density functional theory (DFT/B3LYP) method with 6-311G(d,p) basis set. The optimized geometrical parameters obtained by B3LYP method show good agreement with experimental data.

  2. Synthesis, growth and characterization of organic nonlinear optical material: N-benzyl-2-methyl-4-nitroaniline (BNA)

    Science.gov (United States)

    Kalaivanan, R.; Srinivasan, K.

    2017-05-01

    Synthesis of the organic nonlinear optical compound N-benzyl-2-methyl-4-nitroaniline (BNA) was carried out in a newer chemical environment using the mixture of benzyl chloride and 2-methl-4-nitroaniline by a preferred laboratory synthesis process. The synthesized BNA compound was separated by column chromatography (CC) with low pressure silica gell using petrollium benzine and purity of the separated resultant product was confirmed by thin layer chromatography (TLC). Further, the material was recrystallized atleast four times in methanol and the highly purified BNA was used for the growth of single crystals from solutions with selected solvents by slow evaporation method at room temperature. Single crystals having natural growth morphology were harvested and their different growth faces were identified by optical goniometry. The grown crystals were subjected to different characterization techniques such as powder x-ray diffraction (PXRD), fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC) and UV-vis-Near IR spectroscopy. Further, the second harmonic generation (SHG) efficiency of the grown BNA crystal was studied by Kurtz and Perry powder technique using Nd:YAG laser as fundamental source and found to be twice that of inorganic standard KDP.

  3. Zinc acetylacetonate hydrate adducted with nitrogen donor ligands: Synthesis, spectroscopic characterization, and thermal analysis

    Science.gov (United States)

    Brahma, Sanjaya; Shivashankar, S. A.

    2015-12-01

    We report synthesis, spectroscopic characterization, and thermal analysis of zinc acetylacetonate complex adducted by nitrogen donor ligands, such as pyridine, bipyridine, and phenanthroline. The pyridine adducted complex crystallizes to monoclinic crystal structure, whereas other two adducted complexes have orthorhombic structure. Addition of nitrogen donor ligands enhances the thermal property of these complexes as that with parent metal-organic complex. Zinc acetylacetonate adducted with pyridine shows much higher volatility (106 °C), decomposition temperature (202 °C) as that with zinc acetylacetonate (136 °C, 220 °C), and other adducted complexes. All the adducted complexes are thermally stable, highly volatile and are considered to be suitable precursors for metal organic chemical vapor deposition. The formation of these complexes is confirmed by powder X-ray diffraction, Fourier transform infrared spectroscopy, mass spectroscopy, and elemental analysis. The complexes are widely used as starting precursor materials for the synthesis of ZnO nanostructures by microwave irradiation assisted coating process.

  4. Synthesis, X-ray crystal structure, DNA binding and Nuclease activity ...

    Indian Academy of Sciences (India)

    s12039-016-1125-x. Synthesis, X-ray crystal structure, DNA binding and Nuclease activity of lanthanide(III) complexes of 2-benzoylpyridine acetylhydrazone. KARREDDULA RAJA, AKKILI SUSEELAMMA and KATREDDI HUSSAIN REDDY. ∗.

  5. Synthesis, crystal structure determination of two-dimensional ...

    Indian Academy of Sciences (India)

    Abstract. The 2-D polymeric complex (I) has the formula [Ag(phSE)(NO3)]n, which has been crystallized from methanol-acetonitrile mixture and characterized by elemental analysis and single-crystal X-ray diffraction analysis. In this polymer, each Ag(I) ion occupies distorted trigonal pyramidal geometry coordinating with two.

  6. Growth and characterization of heavily doped silicon crystals

    Energy Technology Data Exchange (ETDEWEB)

    Scala, R.; Porrini, M. [MEMC Electronic Materials SpA, via Nazionale 59, 39012 Merano (Italy); Borionetti, G. [MEMC Electronic Materials SpA, viale Gherzi 31, Novara (Italy)

    2011-08-15

    Silicon crystals grown with the Czochralski method are still the most common material used for the production of electronic devices. In recent years, a growing need of large diameter crystals with increasingly higher doping levels is observed, especially to support the expanding market of discrete devices and its trend towards lower and lower resistivity levels for the silicon substrate. The growth of such heavily doped, large-diameter crystals poses several new challenges to the crystal grower, and the presence of a high dopant concentration in the crystal affects significantly its main properties, requiring also the development of dedicated characterization techniques. This paper illustrates the recent advances in the growth and characterization of silicon crystals heavily doped with antimony, arsenic, phosphorus and boron. (copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  7. New organic single crystal of (benzylthio)acetic acid: Synthesis, crystal structure, spectroscopic (ATR-FTIR, 1H and 13C NMR) and thermal characterization

    Science.gov (United States)

    Sienkiewicz-Gromiuk, Justyna; Tarasiuk, Bogdan; Mazur, Liliana

    2016-04-01

    (Benzylthio)acetic acid (Hbta) was synthesized with 78% yield from benzyl chloride and thiourea as substrates. Well-shaped crystals of Hbta were grown by slow solvent evaporation technique from pure methanol. The compound was investigated by single-crystal X-ray and powder diffraction techniques and was also characterized by other analytical methods, like ATR-FTIR, 1H and 13C NMR and TG/DSC. The acid molecule adopts bent conformation in the solid state. The crystal structure of Hbta is stabilized by numerous intermolecular interactions, including O-H···O, C-H···O, C-H···S and C-H···π contacts. Thermal decomposition of the obtained material takes place above 150 °C.

  8. Synthesis of carbonated hydroxyapatite nanorods in liquid crystals

    Directory of Open Access Journals (Sweden)

    Daniella Dias Palombino de Campos

    2009-09-01

    Full Text Available Syntheses of calcium phosphate nanoparticles, carried out in systems formed from surfactant, oil and water, have resulted in materials with promising possibilities for application. The calcium phosphate particles were synthesized using two different liquid crystals, formed from RenexTM, cyclohexane and a salts solution. The morphology of the nanoparticles synthesized in the liquid crystals is similar to that of hydroxyapatite particles that form bone mineral, where collagen fibers connect these particles so as to form a composite. Therefore, the synthesis of calcium phosphate nanoparticles in the systems used in this work can advance current understanding of mineralization processes that result in the formation of bone mineral.

  9. Silver nanostructures with well-controlled shapes: synthesis, characterization and growth mechanisms

    International Nuclear Information System (INIS)

    Kan Caixia; Zhu Jiejun; Zhu Xiaoguang

    2008-01-01

    This paper describes a poly(vinylpyrollidone)-directed polyol synthesis method for the fabrication of silver (Ag) nanostructures with well-controlled shapes (such as nanorods and nanocubes) by adjusting the synthesizing parameters. The structure characterizations suggest that the Ag nanorods grow from the five-fold twinned decahedral crystal nuclei. The nature of the {1 1 1} planes of Ag crystal and the highly selective poly(vinylpyrollidone) adsorption on the {100} planes of Ag crystal nuclei are favourable for the formation of Ag nanorods and Ag nanowires. The single crystalline Ag nanocubes obtained at optimum conditions are perfect in shape and are enclosed by the {1 0 0} facets. The optical properties of the Ag nanostructures show an attractive plasma resonance, displaying a considerable dependence on the shape and size. The formation of the Ag nanostructures with well-defined shapes is probably due to the fact that the nanostructures are controlled thermodynamically and kinetically. The ability to generate shape-controlled Ag nanostructures also provides an opportunity to experimentally and systematically study the relationship between their properties and geometric shapes

  10. Silver nanostructures with well-controlled shapes: synthesis, characterization and growth mechanisms

    Science.gov (United States)

    Kan, Cai-Xia; Zhu, Jie-Jun; Zhu, Xiao-Guang

    2008-08-01

    This paper describes a poly(vinylpyrollidone)-directed polyol synthesis method for the fabrication of silver (Ag) nanostructures with well-controlled shapes (such as nanorods and nanocubes) by adjusting the synthesizing parameters. The structure characterizations suggest that the Ag nanorods grow from the five-fold twinned decahedral crystal nuclei. The nature of the {1 1 1} planes of Ag crystal and the highly selective poly(vinylpyrollidone) adsorption on the {100} planes of Ag crystal nuclei are favourable for the formation of Ag nanorods and Ag nanowires. The single crystalline Ag nanocubes obtained at optimum conditions are perfect in shape and are enclosed by the {1 0 0} facets. The optical properties of the Ag nanostructures show an attractive plasma resonance, displaying a considerable dependence on the shape and size. The formation of the Ag nanostructures with well-defined shapes is probably due to the fact that the nanostructures are controlled thermodynamically and kinetically. The ability to generate shape-controlled Ag nanostructures also provides an opportunity to experimentally and systematically study the relationship between their properties and geometric shapes.

  11. Synthesis and photocatalytic activity of mesoporous – (001) facets TiO_2 single crystals

    International Nuclear Information System (INIS)

    Dong, Yeshuo; Fei, Xuening; Zhou, Yongzhu

    2017-01-01

    Highlights: • The (001) facets of TiO_2 single crystals with mesoporous structure. • The (010) and (100) facets of TiO_2 single crystals were covered by the flower – shaped TiO_2 crystals. • This special structure could promote charge separation and provide more active sites, which will lead to a substantial increase in photocatalytic activity. - Abstract: In this work, the mesoporous – (001) facets TiO_2 single crystals have been successfully synthesized through a two-step solvothermal route without any template. Their structure and morphology were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), ultraviolet-visible (UV–vis) diffuse reflectance spectroscopy and energy dispersive X-ray spectrometer (EDX). Based on the different characteristics and atomic arrangements on each facet of anatase TiO_2 single crystals, we synthesized these mesoporous – (001) facets TiO_2 single crystals by controlling the interaction characteristics of hydrofluoric acid (HF) and isopropanol (i-PrOH) on the crystal facets. It can been seen that the (001) facets of these as-synthesized TiO_2 single crystals have a clear mesoporous structure through the SEM images and BET methods. Moreover, the other four facets were covered by the flower – shaped TiO_2 crystals with the generation of the mesoporous – (001) facets. This special and interesting morphology could promote charge separation and provide more active sites, which will lead to a substantial increase in photocatalytic activity. Moreover, it is more intuitive to reflect that the different crystal facets possess the different properties due to their atomic arrangement. Besides, according to the different synthetic routes, we proposed and discussed a plausible synthesis mechanism of these mesoporous – (001) facets TiO_2 single crystals.

  12. UHMW Ziegler–Natta polyethylene: Synthesis, crystallization, and melt behavior

    KAUST Repository

    Atiqullah, Muhammad

    2017-04-26

    The fabrication of normal and UHMW PE end-products involves melting and crystallization of the polymer. Therefore, the melt behavior and crystallization of as-synthesized UHMW PE, and NMW PE and E-1-hexene copolymer have been studied using a new nonisothermal crystallization model, Flory\\'s equilibrium theory and ethylene sequence length distribution concept (SLD), Gibbs–Thompson equation, and DSC experiments. By using this approach, the effects of MW, 1-hexene incorporation, ethylene SLD, the level of undercooling θ, and crystal surface free energy D on crystallite stability, relative crystallinity α, instantaneous crystallinity χ, the crystallization kinetic triplet, crystallization entropy, and lamellar thickness distribution (LTD) have been evaluated. Consequently, this study reports insightful new results, interpretations, and explanations regarding the melting and crystallization of the aforementioned polymers. The UHMW PE results significantly differ from the NMW PE and E-1-hexene copolymer ones. Ethylene sequences shorter than the so called minimum crystallizable ethylene sequence length, irrespective of E-1-hexene copolymer MW, can also crystallize. Additionally, the polymer preparation shows that the catalyst coordination environment and symmetry, as well as achiral ethylene versus prochiral α-olefin steric encumbrance and competitive diffusion affect the synthesis of UHMW PE, particularly the corresponding UHMW copolymers.

  13. Synthesis, crystal structure and computational chemistry research of a Zinc(II complex: [Zn(Pt(Biim2

    Directory of Open Access Journals (Sweden)

    Teng Fei

    2012-01-01

    Full Text Available The title metal-organic coordination complex [Zn(pt(Biim2] (pt=phthalic acid, benzene-1,2-dicarboxylate, Biim=2,2'-biimidazole 1 has been obtained by using hydrothermal synthesis and characterized by single-crystal X-ray diffraction. The complex crystallizes in monoclinic, space group P21/n with a = 8.5466(15 Å, b = 11.760(2 Å, c = 20.829(4 Å, β = 95.56(2º, V = 2083.5(6 Å3, Mr =497.78, Dc = 1.587 g/cm3, μ(MoKα = 1.226 mm−1, F(000 = 1016, Z = 4, the final R = 0.0564 and wR = 0.1851 for 3656 observed reflections (I > 2σ(I. The elemental analysis, IR, TG and the theoretical calculation were also investigated.

  14. Hydrothermal synthesis, crystal structures, and enantioselective adsorption property of bis(L-histidinato)nickel(II) monohydrate

    Science.gov (United States)

    Ramos, Christian Paul L.; Conato, Marlon T.

    2018-05-01

    Despite the numerous researches in metal-organic frameworks (MOFs), there are only few reports on biologically important amino acids, histidine in particular, on its use as bridging ligand in the construction of open-framework architectures. In this work, hydrothermal synthesis was used to prepare a compound based on Ni2+ and histidine. The coordination assembly of imidazole side chain of histidine with divalent nickel ions in aqueous condition yielded purple prismatic solids. Single crystal X-ray diffraction (XRD) analysis of the product revealed structure for Ni(C6H8N3O2)2 • H2O that has a monoclinic (C2) structure with lattice parameters, a = 29.41, b = 8.27, c = 6.31 Å, β = 90.01 ˚. Circular dichroism - optical rotatory dispersion (CD-ORD), Powder X-ray diffraction (PXRD) and Fourier transform - infrared spectroscopy (FT-IR) analyses are conducted to further characterize the crystals. Enantioselective adsorption analysis using racemic mixture of 2-butanol confirmed bis(L-histidinato)nickel(II) monohydrate MOF crystal's enantioselective property preferentially favoring the adsorption of (S)-2-butanol isomer.

  15. Synthesis, characterization and photochemistry of a new ...

    Indian Academy of Sciences (India)

    The synthesis, crystal structure, redox characteristics and photochemistry of a new heptamolyb- ... The ability of [Mo7O24]−6 to function as a pure “inor- .... Abbreviations used: bpp = 1,3-bis(4-pyridyl)propane; 2-amp = 2-aminopyridine; DMSO ...

  16. Synthesis and characterization of ceramic powders of pure and doped with trivalent erbium barium tungstate

    International Nuclear Information System (INIS)

    Sousa, R.B. de; Nascimento, V.A. do; Matos, J. M.E. de; Santos, M.R.M.C.

    2014-01-01

    This research proposes the synthesis and characterization of pure and doped with Er"3"+ (1 and 2 %) barium tungstate powders prepared by the coprecipitation method. In order to characterize the obtained powders were used X-Ray Diffractometry, Raman Spectroscopy and Fourier Transform Infrared Spectroscopy. According to the standard XRD spectra, the crystals exhibited the presence of tetragonal scheelite structure without the presence of secondary phases. Raman spectra showed the presence of eleven vibrational modes and two modes were observed in the infrared spectra. The synthesized oxides showed good crystallinity and structurally ordered at short and long-range. (author)

  17. Synthesis and single crystal growth of perovskite semiconductor CsPbBr3

    Science.gov (United States)

    Zhang, Mingzhi; Zheng, Zhiping; Fu, Qiuyun; Chen, Zheng; He, Jianle; Zhang, Sen; Chen, Cheng; Luo, Wei

    2018-02-01

    As a typical representative of all-inorganic lead halide perovskites, cesium lead bromine (CsPbBr3) has attracted significant attention in recent years. The direct band gap semiconductor CsPbBr3 has a wide band gap of 2.25 eV and high average atomic number (Cs: 55, Pb: 82 and Br: 35), which meet most of the requirements for detection of X- and γ-ray radiation, such as high attenuation, high resistivity, and significant photoconductivity response. However, the growth of large volume CsPbBr3 single crystals remains a challenge. In this paper, the synthesis of CsPbBr3 polycrystalline powders by a chemical co-precipitation method was investigated and the optimum synthesis conditions were obtained. A large CsPbBr3 single crystal of 8 mm diameter and 60 mm length was obtained by a creative electronic dynamic gradient (EDG) method. X-ray diffraction (XRD) patterns and X-ray rocking curve showed that the CsPbBr3 crystal preferentially oriented in the (1 1 0) direction and had a low dislocation density and small residual stress in the crystal. The IR and UV-Vis transmittance and temperature-dependent photoluminescence (PL) spectra showed the crystal had a good basic optical performance. The almost linear current-voltage (I-V) curves implied good ohmic contact between the electrodes and crystal surfaces. The resistivity of the crystal was calculated 109-1010 Ω cm. The above results showed that the quality of the obtained crystal had met the demand of optoelectronic applications.

  18. Synthesis, growth, morphology and characterization of ferroelectric glycine phosphite single crystals

    Energy Technology Data Exchange (ETDEWEB)

    Devi, K. Renuka; Srinivasan, K. [Crystal Growth Laboratory, Department of Physics, School of Physical Sciences, Bharathiar University, Tamil Nadu (India)

    2011-12-15

    Glycine phosphite (NH{sub 3}CH{sub 2}COO.H{sub 3}PO{sub 3}), a potential ferroelectric material, was grown as single crystals from aqueous solutions by slow evaporation and slow cooling methods. Laboratory synthesized title compound was purified by recrystallization method and confirmed by Fourier transform infrared and Laser Raman studies. Temperature dependent solubility in double distilled water in the range between 288 and 328 K was determined by gravimetric method. Morphological importance of various growth faces were studied by optical goniometry. Powder x-ray diffraction study performed on the grown crystals confirms the crystal system and lattice parameters of the unit cell. Optical transparency of the grown crystals in the ultraviolet-visible -near infrared region was studied by spectroscopic method. Thermal stability of the grown crystals in the temperature region above ambient until melting was studied using differential scanning calorimetry. (copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  19. Nano crystals-Related Synthesis, Assembly, and Energy Applications 2012

    International Nuclear Information System (INIS)

    Zou, B.; Yu, W.W.; Seo, J.; Zhu, T.; Hu, M.Z.

    2012-01-01

    During the past decades, nano crystals have attracted broad attention due to their unique shape- and size-dependent physical and chemical properties that differ drastically from their bulk counterparts. Hitherto, much effort has been dedicated to achieving rational controlling over the morphology, assembly, and related energy applications of the nano materials. Therefore, the ability to manipulate the morphology, size, and size distribution of inorganic nano materials is still an important goal in modern materials physics and chemistry. Especially, the world's demand for energy supply is causing a dramatic escalation of social and political unrest. Likewise, the environmental impact of the global climate change due to the combustion of fossil fuel is becoming increasingly alarming. These problems compel us to search for effective routes to build devices that can supply sustainable energy, with not only high efficiency but also environmental friendship. One of ways to relieve the energy crisis is to exploit devices based on renewable energy sources, such as solar energy and water power. Aiming at this exploration, the primary stage requires the design of appropriate strategies for the synthesis of high-quality nano crystals with respect to size uniformity and superior electrochemical performances. As a consequence, we organize the current special issue for Journal of Nano materials to provide the authors with a platform and readers with the latest achievements of nano crystals-related synthesis, assembly, and energy applications.

  20. Synthesis and structural characterization of lithium

    Indian Academy of Sciences (India)

    synthesis and characterization of two new iminophos- phonamine ligands ... structures. 2.3 General synthetic method for ligands (1 and 2) ... 2.3b General method for the Synthesis of ligands ...... studies are currently underway in our laboratory.

  1. Crystal structure and optical properties of silver nanorings

    Science.gov (United States)

    Zhou, Li; Fu, Xiao-Feng; Yu, Liao; Zhang, Xian; Yu, Xue-Feng; Hao, Zhong-Hua

    2009-04-01

    We report the polyol synthesis and crystal structure characterization of silver nanorings, which have perfect circular shape, smooth surface, and elliptical wire cross-section. The characterization results show that the silver nanorings have well-defined crystal of singly twinned along the whole ring. The spatial distribution of the scattering of a silver nanoring with slanted incidence reveals the unique focus effect of the nanoring, and the focus scattering varies with the incident wavelength. The silver nanorings with perfect geometry and well-defined crystal have potential applications in nanoscaled photonics, plasmonic devices, and optical manipulation.

  2. Reduce synthesis temperature and improve dispersion of YAG nanopowders based on the co-crystallization method

    Energy Technology Data Exchange (ETDEWEB)

    Fan, G.F.; Tang, Y.Q.; Lu, W.Z., E-mail: lwz@mail.hust.edu.cn; Zhang, X.R.; Xu, X.

    2015-01-05

    Highlights: • YAG nanopowders were synthesized through a co-crystallization method. • A three-layer core–shell structure was made to lower the synthesis temperature. • PAA again reduced the synthesis temperature based on the core–shell structure. • YAG nanopowders were synthesized at 700 °C in normal apparatus. • Agglomeration was greatly improved by PAA. - Abstract: Pure yttrium aluminum garnet (YAG) nanopowders were synthesized at 950 °C from the co-crystallization precursor of Y(NO{sub 3}){sub 3}⋅6H{sub 2}O and Al(NO{sub 3}){sub 3}⋅9H{sub 2}O (nitrate process). When 17 wt.% of Y(NO{sub 3}){sub 3}⋅6H{sub 2}O was replaced by Y{sub 2}O{sub 3} nanopowders, so as to make up a three-layer core–shell structure of the precursor, the synthesis temperature was reduced to 850 °C (Y{sub 2}O{sub 3} process). Based on Y{sub 2}O{sub 3} process, further reducing the synthesis temperature to 700 °C was realized by adding polyacrylic acid (PAA, 50% M), which was used to shorten the distance of the metal ions and provide combustion heat (PAA process). TEM characterizations indicated that the powders produced through nitrate and Y{sub 2}O{sub 3} processes agglomerated, while the powders produced through PAA process were dispersed much better. The agglomerate size analysis results demonstrated that the powders produced through PAA process were with smaller agglomerate size and wider agglomerate size distribution than those through nitrate process or Y{sub 2}O{sub 3} process. And they were more likely to be sintered to YAG transparent ceramics.

  3. SYNTHESIS, CHARACTERIZATION AND PHOTOCATALYTIC ...

    African Journals Online (AJOL)

    ISSN 1011-3924. © 2018 Chemical Society of Ethiopia and The Authors. Printed in Ethiopia ... SYNTHESIS, CHARACTERIZATION AND PHOTOCATALYTIC ACTIVITY OF .... cm−1 to determine the surface functional groups. 10 mg of sample ...

  4. Silver nanostructures with well-controlled shapes: synthesis, characterization and growth mechanisms

    Energy Technology Data Exchange (ETDEWEB)

    Kan Caixia [College of Science, Nanjing University of Aeronautics and Astronautics, Nanjing 211100 (China); Zhu Jiejun [Department of Physics, Nanjing University, Nanjing 210093 (China); Zhu Xiaoguang [Institute of Solid State Physics, Chinese Academy of Sciences, Hefei 230031 (China)], E-mail: cxkan@nuaa.edu.cn

    2008-08-07

    This paper describes a poly(vinylpyrollidone)-directed polyol synthesis method for the fabrication of silver (Ag) nanostructures with well-controlled shapes (such as nanorods and nanocubes) by adjusting the synthesizing parameters. The structure characterizations suggest that the Ag nanorods grow from the five-fold twinned decahedral crystal nuclei. The nature of the {l_brace}1 1 1{r_brace} planes of Ag crystal and the highly selective poly(vinylpyrollidone) adsorption on the {l_brace}100{r_brace} planes of Ag crystal nuclei are favourable for the formation of Ag nanorods and Ag nanowires. The single crystalline Ag nanocubes obtained at optimum conditions are perfect in shape and are enclosed by the {l_brace}1 0 0{r_brace} facets. The optical properties of the Ag nanostructures show an attractive plasma resonance, displaying a considerable dependence on the shape and size. The formation of the Ag nanostructures with well-defined shapes is probably due to the fact that the nanostructures are controlled thermodynamically and kinetically. The ability to generate shape-controlled Ag nanostructures also provides an opportunity to experimentally and systematically study the relationship between their properties and geometric shapes.

  5. Lead sulfide nano crystal preparation and characterization

    International Nuclear Information System (INIS)

    Sasani Ghamsari, M.

    1999-01-01

    Nanometer sized semiconductor particles have attracted much attention duo to their novel electronic and optical optical proportion, originating from quantum confinement. Pb S is one of the most important semiconductor material. In this project Pb S semiconductor nano crystal is synthesized in order to decrease particle size and study the modifications of their optical properties in relation to their size. The synthesis is carried out by using the technique of colloid chemistry. In this method we use lead nitrate extra pure and H2 S gas which is solved in the water. EDTA is used for controlling of particle size. A fast evolution of the optical absorption spectrum will be noticed following synthesis. Immediately after the synthesis reaction. The sample, exhibit a structured absorption spectrum with well defined excitonic peak in 240 nm theoretical relations is that shown this peak belong to 5 A particles. X-ray diffraction is used to establish the identity, phase and the size of these clusters

  6. Mechanochemical synthesis and structural characterization of three novel cocrystals of dimethylglyoxime with N-heterocyclic aromatic compounds and acetamide

    Science.gov (United States)

    Abidi, Syed Sibte Asghar; Azim, Yasser; Gupta, Abhishek Kumar; Pradeep, Chullikkattil P.

    2017-12-01

    With an aim to explore the interactions of (RR'Cdbnd Nsbnd OH) oxime moiety of dimethylglyoxime (DMG) with pyridyl ring of N-heterocyclic aromatic compounds and acetamide, three novel cocrystals of dimethylglyoxime with acridine (ACR), 1,10-phenanthroline monohydrate (PT) and acetamide (ACT) are reported. These three cocrystals were obtained with a mechanochemical synthesis approach and were characterized by single crystal X-ray diffraction (SCXRD), powder X-ray diffraction (PXRD), fourier transform-infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). Additionally, Hirshfeld surface analysis is used to investigate the intermolecular interaction and the crystal packing of cocrystals.

  7. Synthesis and Characterization of Novel Ternary and Quaternary Alkali Metal Thiophosphates

    KAUST Repository

    Alahmary, Fatimah S.

    2014-05-01

    The ongoing development of nonlinear optical (NLO) crystals such as coherent mid-IR sources focuses on various classes of materials such as ternary and quaternary metal chalcophosphates. In case of thiophosphates, the connection between PS4-tetrahedral building blocks and metals gives rise to a broad structural variety where approximately one third of all known ternary (A/P/S) and quaternary (A/M/P/S) (A = alkali metal, M = metal) structures are acentric and potential nonlinear optical materials. The molten alkali metal polychalcophosphate fluxes are a well-established method for the synthesis of new ternary and quaternary thiophosphate and selenophosphate compounds. It has been a wide field of study and investigation through the last two decades. Here, the flux method is used for the synthesis of new quaternary phases containing Rb, Ag, P and S. Four new alkali metal thiophosphates, Rb4P2S10, RbAg5(PS4), Rb2AgPS4 and Rb3Ag9(PS4)4, have been synthesized successfully from high purity elements and binary starting materials. The new compounds were characterized by single crystal and powder X-ray diffraction, scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), ultraviolet-visible (UV-VIS), Raman spectroscopy, thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). These compounds show interesting structural variety and physical properties. The crystal structures feature 3D anionic framework built up of PS4 tetrahedral units and charge balanced by Ag and alkali metal cations. All prepared compounds are semiconductors with band gap between 2.3 eV to 2.6 eV and most of them are thermally stable up to 600ºC.

  8. Mesoporous zeolite and zeotype single crystals synthesized in fluoride media

    DEFF Research Database (Denmark)

    Egeblad, Kresten; Kustova, Marina; Klitgaard, Søren Kegnæs

    2007-01-01

    We report the synthesis and characterization of a series of new mesoporous zeolite and zeotype materials made available by combining new and improved procedures for directly introducing carbon into reaction mixtures with the fluoride route for conventional zeolite synthesis. The mesoporous...... materials were all prepared by hydrothermal crystallization of gels adsorbed on carbon matrices which were subsequently removed by combustion. The procedures presented here resulted in mesoporous zeolite and zeotypes materials with MFI, MEL, BEA, AFI and CHA framework structures. All samples were...... characterized by XRPD, SEM, TEM and N-2 physisorption measurements. For the zeolite materials it A as found that mesoporous MFI and MEL structured single crystals could indeed be crystallized from fluoride media using an improved carbon-templating approach. More importantly, it was found that mesoporous BEA...

  9. Synthesis, characterization and x-ray crystal structure of a dimethyltin (IV) dichloride complex of 2-acetylpyridine benzophenone azine

    International Nuclear Information System (INIS)

    Mustaffa Shamsuddin; Md Abu Affan; Ramli Atan

    1998-01-01

    Dimethyltin dichloride react with 2-ac ethylpyridine benzophenone azine (apba) in refluxing dry hexane to give (SnMe 2 Cl 2 (apba)) where the azine ligand acts as a bidentate N-N chelating ligand. The complex has been characterized by IR spectroscopy, 1 H and 13 C NMR spectroscopic data and elemental analyses. The crystal structure of the dimethyltin(IV) derivative has also been determined. Crystals are monoclinic with space group P2(1)/n with cell dimensions: a = 10.1819(3) Armstrong, b = 18.3113(5) Armstrong, c = 12.6451(4) Armstrong

  10. Ion beam assisted synthesis of nano-crystals in glasses (silver and lead chalcogenides)

    International Nuclear Information System (INIS)

    Espiau de Lamaestre, R.

    2005-04-01

    This work deals with the interest in ion beams for controlling nano-crystals synthesis in glasses. We show two different ways to reach this aim, insisting on importance of redox phenomena induced by the penetration and implantation of ions in glasses. We first show that we can use the great energy density deposited by the ions to tailor reducing conditions, favorable to metallic nano-crystal precipitation. In particular, we show that microscopic mechanism of radiation induced silver precipitation in glasses are analogous to the ones of classical photography. Ion beams can also be used to overcome supersaturation of elements in a given matrix. In this work, we synthesized lead chalcogenide nano-crystals (PbS, PbSe, PbTe) whose optical properties are interesting for telecommunication applications. We demonstrate the influence of complex chalcogenide chemistry in oxide glasses, and its relationship with the observed loss of growth control when nano-crystals are synthesized by sequential implantation of Pb and S in pure silica. As a consequence of this understanding, we demonstrate a novel and controlled synthesis of PbS nano-crystals, consisting in implanting sulfur into a Pb-containing glass, before annealing. Choice of glass composition provides a better control of precipitation physico-chemistry, whereas the use of implantation allows high nano-crystal volume fractions to be reached. Our study of IR emission properties of these nano-crystals shows a very high excitation cross section, and evidence for a 'dark exciton' emitting level. (author)

  11. Study on the NaOH/metakaolin ratio and crystallization time for zeolite a synthesis from kaolin using statistical design

    Energy Technology Data Exchange (ETDEWEB)

    Silva Filho, Severino Higino da; Bieseki, Lindiane; Pergher, Sibele Berenice Castella, E-mail: sibelepergher@gmail.com [Universidade Federal do Rio Grande do Norte (LABPEMOL/UFRN), Natal, RN (Brazil). Lab. de Peneiras Moleculares; Maia, Ana Aurea B.; Angelica, Romulo Simoes [Universidade Federal do Para (UFPA), Belem PA (Brazil); Treichel, Helen [Universidade Federal da Fronteira Sil (UFFS), Erechim, RS (Brazil)

    2017-05-15

    The NaOH/metakaolin ratio and crystallization time were studied for the synthesis of zeolite NaA from a sample of kaolin from a Capim mine. The tests were carried out by using statistical design with axial points and replication of the central point. The samples obtained were characterized by X-ray diffraction (DRX), scanning electron microscopy and chemical analysis using a microprobe EPMA. The results showed that there is a relationship between the amount of NaOH added and crystallization time. The tests carried out using the lowest NaOH/metakaolin ratio (0.5) and the shortest time (4 h) produced a non-crystalline material. On the other hand, increasing the NaOH/metakaolin ratio and the crystallization time led to the formation of a NaA phase with a high structural level, but with the presence of a sodalite phase as an impurity. (author)

  12. On-Surface Synthesis and Characterization of Honeycombene Oligophenylene Macrocycles.

    Science.gov (United States)

    Chen, Min; Shang, Jian; Wang, Yongfeng; Wu, Kai; Kuttner, Julian; Hilt, Gerhard; Hieringer, Wolfgang; Gottfried, J Michael

    2017-01-24

    We report the on-surface formation and characterization of [30]-honeycombene, a cyclotriacontaphenylene, which consists of 30 phenyl rings (C 180 H 120 ) and has a diameter of 4.0 nm. This shape-persistent, conjugated, and unsubstituted hexagonal hydrocarbon macrocycle was obtained by solvent-free synthesis on a silver (111) single-crystal surface, making solubility-enhancing alkyl side groups unnecessary. Side products include strained macrocycles with square, pentagonal, and heptagonal shape. The molecules were characterized by scanning tunneling microscopy and density functional theory (DFT) calculations. On the Ag(111) surface, the macrocycles act as molecular quantum corrals and lead to the confinement of surface-state electrons inside the central cavity. The energy of the confined surface state correlates with the size of the macrocycle and is well described by a particle-in-the-box model. Tunneling spectroscopy suggests conjugation within the planar rings and reveals influences of self-assembly on the electronic structure. While the adsorbed molecules appear to be approximately planar, the free molecules have nonplanar conformation, according to DFT.

  13. Growth and Characterization of Tetraphenylphosphonium Bromide Crystal

    Directory of Open Access Journals (Sweden)

    Guangqiang Wang

    2017-05-01

    Full Text Available Multiple-phenyl phosphorous compounds are a group of chemical materials that have been used as reactants, pharmaceutical intermediates, extractants, and catalysts in organic synthetic reactions. However, the crystal growth of bulk crystals of multiple-phenyl phosphorous compounds, which may expand their applications in photonics technology, have been largely overlooked. In this article, the crystal growth of tetraphenylphosphonium bromide (TPPB has been studied in organic solvents and water. The crystal structures and crystallization features are analyzed by X-ray diffraction data. By a slow temperature-lowering method, a single-crystal of TPPB (2H2O with the size of 27 × 20 × 20 mm3 has been obtained in water. The basic thermal and optical properties were characterized. We find that the TPPB (2H2O crystal shows excellent transparent property in the near-IR region. Large Raman shifts and strong Raman scattering intensity indicate that TPPB is a potential candidate in Raman-scattering-based nonlinearity applications.

  14. Synthesis of zeolite-like crystals by means of sorption of bases on polysilicic acids

    Energy Technology Data Exchange (ETDEWEB)

    Belyakova, L A; Il' in, V G; Peresun' ko, T F; Kryuchkova, I I; Neymark, I E [AN Ukrainskoj SSR, Kiev. Inst. Fizicheskoj Khimii

    1974-11-21

    Investigation into the sorption of bases on crystalline polysilicic acids is of particular interest from the viewpoint of synthesis of new types of porous zeolite-like materials. A synthesis of polysilicate acids was carried out by treating respective sodium polysilicates with mineral acid solutions. The sorption of alkali metal hydroxides in the neutral and alkaline pH region was studied by the method of potentiometric titration of individual weighed quantities. A marked sorption of alkali metal hydroxides on polysilicic acids starts in the weakly acid and neutral regions and reaches saturation at pH=10.5. The process of ion exchange is accompanied by a change in the crystal structure of polysilicic acids. The sorption of bases on polysilicic acids may be used as a method of synthesis of zeolite-like porous crystals in different cationic forms.

  15. Synthesis of zeolite-like crystals by means of sorption of bases on polysilicic acids

    International Nuclear Information System (INIS)

    Belyakova, L.A.; Il'in, V.G.; Peresun'ko, T.F.; Kryuchkova, I.I.; Nejmark, I.E.

    1974-01-01

    Investigation into the sorption of bases on crystalline polysilicic acids is of particular interest from the viewpoint of synthesis of new types of porous zeolite-like materials. A synthesis of polysilicate acids was carried out by treating respective sodium polysilicates with mineral acid solutions. The sorption of alkali metal hydroxides in the neutral and alkaline pH region was studied by the method of potentiometric titration of individual weighed quantities. A marked sorption of alkali metal hydroxides on polysilicic acids starts in the weakly acid and neutral regions and reaches saturation at pHapproximately10.5. The process of ion exchange is accompanied by a change in the crystal structure of polysilicic acids. The sorption of bases on polysilicic acids may be used as a method of synthesis of zeolite-like porous crystals in different cationic forms

  16. Synthesis and Characterization of High Aluminum Zeolite X from Technical Grade Materials

    Directory of Open Access Journals (Sweden)

    Seyed Kamal Masoudian

    2013-06-01

    Full Text Available Zeolites are widely used as ion exchangers, adsorbents, separation materials and catalyst due to their well-tailored and highly-reproducible structures; therefore, the synthesis of zeolite from low grade resources can be interested. In the present work, high aluminum zeolite X was prepared from mixing technical grade sodium aluminate and sodium silicate solutions at temperatures between 70°C and 100°C. The synthesized zeolite X was characterized by SEM and X-ray methods according to ASTM standard procedures. The results showed that aging of the synthesis medium at the room temperature considerably increased the selectivity of zeolite X formation. On the other hand, high temperature of reaction mixture during crystallization formed zeolite A in the product; therefore, it decreased the purity of zeolite X. In addition, it was found that increasing H2O/Na2O and decreasing Na2O/SiO2 molar ratios in the reaction mixture resulted product with higher purity. © 2013 BCREC UNDIP. All rights reservedReceived: 7th January 2013; Revised: 7th April 2013; Accepted: 19th April 2013[How to Cite: Masoudian, S. K., Sadighi, S., Abbasi, A. (2013. Synthesis and Characterization of High Alu-minum Zeolite X from Technical Grade Materials. Bulletin of Chemical Reaction Engineering & Catalysis, 8 (1: 54-60. (doi:10.9767/bcrec.8.1.4321.54-60][Permalink/DOI: http://dx.doi.org/10.9767/bcrec.8.1.4321.54-60] | View in  |

  17. Synthesis and structural characterization of CsNiP crystal

    Indian Academy of Sciences (India)

    Unknown

    The crystals obtained by this method were of good quality exhibiting ... type framework structure having Cs atoms inside it (figures. 3 and 4). This helps for .... Gopalakrishna G S, Prasad J S and Lokanath N K 2001 Proc. joint 4th and 6th ICSTR ...

  18. Synthesis, characterization, and application of two Al(OR(F))3 Lewis superacids.

    Science.gov (United States)

    Kraft, Anne; Trapp, Nils; Himmel, Daniel; Böhrer, Hannes; Schlüter, Peter; Scherer, Harald; Krossing, Ingo

    2012-07-23

    We report herein the synthesis and full characterization of the donor-free Lewis superacids Al(OR(F))(3) with OR(F) = OC(CF(3))(3) (1) and OC(C(5)F(10))C(6)F(5) (2), the stabilization of 1 as adducts with the very weak Lewis bases PhF, 1,2-F(2)C(6)H(4), and SO(2), as well as the internal C-F activation pathway of 1 leading to Al(2)(F)(OR(F))(5) (4) and trimeric [FAl(OR(F))(2)](3) (5, OR(F) = OC(CF(3))(3)). Insights have been gained from NMR studies, single-crystal structure determinations, and DFT calculations. The usefulness of these Lewis acids for halide abstractions has been demonstrated by reactions with trityl chloride (NMR; crystal structures). The trityl salts allow the introduction of new, heteroleptic weakly coordinating [Cl-Al(OR(F))(3)](-) anions, for example, by hydride or alkyl abstraction reactions. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Synthesis and Characterization of Nanocrystalline Aluminophosphate AlPO4-5 Molecular Sieve

    Directory of Open Access Journals (Sweden)

    Asir Alnaama

    2018-03-01

    Full Text Available Nanocrystalline aluminophosphate AlPO4-5 molecular sieves were synthesized by hydrothermal method (HTS. Synthesis parameters like time and temperature of crystallization were investigated. Type of template (R and ratio of R/P2O5 were studied also. Characterization of the synthesized AlPO4-5 were done by powder X-ray diffraction (XRD, scanning electron microscopy (SEM/EDX, Fourier transform infrared (FTIR, differential scanning calorimetry-thermogravimetry analysis (DSC-TGA, and N2 adsorption-desorption BET analysis. XRD patterns results showed excellent crystallinity for two types of templates, di-n-propylamine (DPA and tetrapropyl ammonium hydroxide (TPAOH for alumminophosphate five (AFI structure. Nano-level for particle size of 66 nm was revealed by AFM test. Good thermal stability was obtained in DSC-TGA results. Best time and temperature of crystallization of 24h and 190 O C were got. Optimum R/P2O5 for two kind of template was established.

  20. Synthesis, characterization and crystal structure of (2RS,4R)-2-(2-hydroxy-3-methoxyphenyl)thiazolidine-4-carboxylic acid

    Science.gov (United States)

    Muche, Simon; Müller, Matthias; Hołyńska, Małgorzata

    2018-03-01

    The condensation reaction of ortho-vanillin and L-cysteine leads to formation of a racemic mixture of (2RS,4R)-2-(2-hydroxy-3-methoxyphenyl)thiazolidine-4-carboxylic acid and not, as reported in the available literature, to a Schiff base. The racemic mixture was fully characterized by 1D and 2D NMR techniques, ESI-MS and X-ray diffraction. Addition of ZnCl2 led to formation of crystals in form of colorless needles, suitable for X-ray diffraction studies. The measured crystals were identified as the diastereomer (2R,4R)-2-(2-hydroxy-3-methoxyphenyl)thiazolidine-4-carboxylic acid 1. The bulk material is racemic. Thiazolidine exists as zwitterion in solid state, as indicated by the crystal structure.

  1. Synthesis and characterization of six-membered pincer ...

    Indian Academy of Sciences (India)

    0013167

    SUPPORTING INFORMATION. REGULAR ARTICLE. Synthesis and characterization of six-membered pincer nickelacycles and application in alkylation of benzothiazole. †. HANUMANPRASAD PANDIRI,a DIPESH M SHARMA,a RAJESH G GONNADEb and. BENUDHAR PUNJI*,a. aOrganometallic Synthesis and Catalysis ...

  2. Hydrothermal synthesis of magnetite particles with uncommon crystal facets

    Directory of Open Access Journals (Sweden)

    Junki Sato

    2014-09-01

    Full Text Available Hydrothermal synthesis of Fe3O4 (magnetite particles was carried out using organic compounds as morphology control agents to obtain magnetite crystals with uncommon facets. It was established that the morphology of Fe3O4 crystals obtained by hydrothermal treatment of an aqueous solution containing Fe2+ and organic compounds depended on the organic compound used. The shape of the Fe3O4 particles obtained when no additives were used was quasi-octahedral. In contrast, the addition of picolinic acid, citric acid or pyridine resulted in the formation of polyhedral crystals, indicating the presence of not only {1 1 1}, {1 0 0} and {1 1 0} facets but also high-index facets including at least {3 1 1} and {3 3 1}. When citric acid was used as an additive, octahedral crystals with {1 1 1} facets also appeared, and their size decreased as the amount of citric acid was increased. Thus, control of Fe3O4 particle morphology was achieved by a simple hydrothermal treatment using additives.

  3. Simple and Efficient One-Pot Synthesis, Spectroscopic Characterization and Crystal Structure of Methyl 5-(4-Chlorobenzoyloxy-1-phenyl-1H-pyrazole-3-carboxylate

    Directory of Open Access Journals (Sweden)

    Imtiaz Khan

    2012-07-01

    Full Text Available A facile one-pot synthesis of methyl 5-(4-chlorobenzoyloxy-1-phenyl-1H-pyrazole-3-carboxylate (4 is described. The title compound was efficiently synthesized by the reaction of phenyl hydrazine, dimethyl acetylenedicarboxylate and 4-chlorobenzoyl chloride in dichloromethane under reflux in good yield. The structure of the target compound was deduced by modern spectroscopic and analytical techniques and unequivocally confirmed by a single crystal X-ray diffraction analysis. The crystal of the title compound belongs to orthorhombic system, space group P 21 21 21 with cell parameters a = 6.6491(3 Å, b = 7.9627(6 Å, c = 30.621(5 Å, α = β = γ = 90° and Z = 4. The crystal packing of the compound (4 is stabilized by an offset π-stacking between the planar benzoyl-substituted diazole moieties.

  4. Synthesis, characterization and single crystal X-ray analysis of chlorobis(N,N-dimethyldithiocarbamato-S,S′antimony(III

    Directory of Open Access Journals (Sweden)

    H.P.S. Chauhan

    2015-07-01

    Full Text Available The title compound chlorobis(N,N-dimethyldithiocarbamato-S,S′antimony(III has been prepared in distilled acetonitrile and characterized by physicochemical [melting point and molecular weight determination, elemental analysis (C, H, N, S & Sb], spectral [FT–IR, far IR, NMR (1H & 13C] studies. The crystal and molecular structure was further confirmed using single crystal X-ray diffraction analysis which features a five-coordinate geometry for antimony(III within a ClS4 donor set. The distortion in the co-planarity of ClSbS3 evidences the stereochemical influence exerts by the lone pair of electrons on antimony(III. Two centrosymmetrically related molecule held together via C–H···Cl secondary interaction result in molecular aggregation of the compound.

  5. Chromium(III) Complex Obtained from Dipicolinic Acid: Synthesis, Characterization, X-Ray Crystal Structure and Electrochemical Studies

    Energy Technology Data Exchange (ETDEWEB)

    Ghasemi, Khaled; Rezvani, Ali Reza; Ghasemi, Fatemeh [Univ. of Sistan and Baluchestan, Zahedan (Iran, Islamic Republic of); Razak, Ibrahim Abdul; Rosli, Mohd Mustaqim [Universiti Sains Malaysia, Penang (Malaysia)

    2013-10-15

    The synthesis, X-ray crystallography, spectroscopic (IR, UV-vis), and electrochemical properties of the title compound, [H{sub 3}O][Cr(dipic){sub 2}] [H{sub 3}O{sup +}.Cl{sup -}] (1), (H{sub 2}dipic = 2,6-pyridinedicarboxylic acid), are reported. This complex crystallizes in the monoclinic space group Cc with a = 14.9006(10) A, b = 12.2114(8) A, c = 8.6337(6) A, α = 90.00 .deg., β = 92.7460(10) .deg., γ = 90.00 .deg., and V = 1569.16(18) A3 with Z = 4. The hydrogen bonding and noncovalent interactions play roles in the stabilization of the structure. In order to gain a better understanding of the most important geometrical parameters in the structure of the complex, atoms in molecules (AIM) method at B3LYP/6-31G level of theory has been employed.

  6. Copper nanoparticles mediated by chitosan: synthesis and characterization via chemical methods.

    Science.gov (United States)

    Usman, Muhammad Sani; Ibrahim, Nor Azowa; Shameli, Kamyar; Zainuddin, Norhazlin; Yunus, Wan Md Zin Wan

    2012-12-14

    Herein we report a synthesis of copper nanoparticles (Cu-NPs) in chitosan (Cts) media via a chemical reaction method. The nanoparticles were synthesized in an aqueous solution in the presence of Cts as stabilizer and CuSO(4)·5H(2)O precursor. The synthesis proceeded with addition of NaOH as pH moderator, ascorbic acid as antioxidant and hydrazine( )as the reducing agent. The characterization of the prepared NPs was done using ultraviolet-visible spectroscopy, which showed a 593 nm copper band. The Field Emission Scanning Electron Microscope (FESEM) images were also observed, and found to be in agreement with the UV-Vis result, confirming the formation of metallic Cu-NPs. The mean size of the Cu-NPs was estimated to be in the range of 35-75 nm using X-ray diffraction. XRD was also used in analysis of the crystal structure of the NPs. The interaction between the chitosan and the synthesized NPs was studied using Fourier transform infrared (FT-IR) spectroscopy, which showed the capping of the NPs by Cts.

  7. Synthesis, Crystal structure and Characterization of a New Oxalate ...

    Indian Academy of Sciences (India)

    in a slightly distorted octahedral environment, by two O atoms from two water molecules and four O atoms of two oxalate anions acting as chelating ligands. ... component for building up supramolecular systems and for participating in hydrogen bonding ... heating rate of 10◦C min−1. 2.2 Synthesis of the complex. Aqueous ...

  8. Neutral, seven-coordinate dioxime complexes of technetium(III): Synthesis and characterization

    International Nuclear Information System (INIS)

    Linder, K.E.; Malley, M.F.; Gougoutas, J.Z.; Unger, S.E.; Nunn, A.D.

    1990-01-01

    The tin-capped complexes 99 Tc(oxime) 3 (μ-OH)SnCl 3 [oxime = dimethylglyoxime (DMG) or cyclohexanedione dioxime (CDO)] can be prepared by the reduction of NH 4 TcO 4 with 2 equiv of SnCl 2 in the presence of dioxime and HCl. These tin-capped complexes can be readily converted into a new class of uncapped Tc-dioxime compounds, TcCl(oxime) 3 , by treatment with HCl. This reaction is reversible. Both the tin-capped and uncapped tris(dioxime) complexes can be converted to the previously reported boron-capped Tc-dioxime complexes TcCl(oxime) 3 BR (R = alkyl, OH) by reaction with boronic acids or with boric acid at low pH. All of these complexes [Tc(oxime) 3 (μ-OH)SnCl 3 , TcCl(oxime) 3 , and TcCl(oxime) 3 BR] appear to be neutral, seven-coordinate compounds of technetium(III). They have been characterized by elemental analysis, 1 H NMR and UV/visible spectroscopy, conductivity, and fast atom bombardment mass spectrometry. The synthesis, characterization, and reactivity of these compounds is discussed. The x-ray crystal structure analysis of TcCl(DMG) 3 and an abbreviated structure report on TcCl(DMG) 3 MeB are described. Crystal data for TcCl(DMG) 3 are reported. 23 refs., 6 figs., 5 tabs

  9. Synthesis of sub-millimeter calcite from aqueous solution

    Science.gov (United States)

    Reimi, M. A.; Morrison, J. M.; Burns, P. C.

    2011-12-01

    A novel aqueous synthesis that leads to the formation of calcite (CaCO3) crystals, up to 500μm in diameter, will be used to facilitate the study of contaminant transport in aqueous environmental systems. Existing processes tend to be complicated and often yield nanometer-sized or amorphous CaCO3. The synthesis method presented here, which involves slow mixing of concentrated solutions of CaCl2 ¬and (NH4)2CO3, produces single crystals of rhombohedral calcite in 2 to 4 days. Variations on the experimental method, including changes in pH and solution concentration, were explored to optimize the synthesis. Scanning Electron Microscope images show the differences in size and purity observed when the crystals are grown at pH values ranging from 2 to 6. The crystals grown from solutions of pH 2 were large (up to 500 micrometers in diameter) with minimal polycrystalline calcium carbonate, while crystals grown from solutions with pH values beyond 4 were smaller (up to 100 micrometers in diameter) with significant polycrystalline calcium carbonate. The synthesis method, materials characterization, and use in future actinide contaminant studies will be discussed.

  10. Synthesis and characterization of thorium(IV) and uranium(IV) complexes with Schiff bases

    Energy Technology Data Exchange (ETDEWEB)

    Radoske, Thomas; Maerz, Juliane; Kaden, Peter; Patzschke, Michael; Ikeda-Ohno, Atsushi [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). Chemistry of the F-Elements

    2017-06-01

    We report herein the synthesis and characterization of several imine complexes of tetravalent thorium (Th(IV)) and uranium (U(IV)). The ligands investigated in this study are a Schiff base type, including the well-known salen ligand (H{sub 2}Le, Fig. 1). The complexation in solution was investigated by NMR measurements indicating paramagnetic effects of unpaired f-electrons of U(IV) on the ligand molecule. We also determined the solid-state molecular structures of the synthesized complexes by single crystal X-ray diffraction. The synthesized complexes show an eight-fold coordination geometry around the actinide center surrounded by two tetradentate ligands with 2N- and 2O-donor atoms.

  11. Design, synthesis and crystallization of a novel glucagon analog as a therapeutic agent

    Energy Technology Data Exchange (ETDEWEB)

    Li, Pengyun; Rogers, Tanya; Smiley, David; DiMarchi, Richard D.; Zhang, Faming, E-mail: fzhang@indiana.edu [Department of Chemistry and Biochemistry Program, Indiana University, Bloomington, Indiana 47405 (United States)

    2007-07-01

    The synthesis and crystallization of glucagon-Cex are reported. Glucagon and glucagon-like peptide 1 (GLP-1) are drugs or drug candidates for the treatment of metabolic diseases such as diabetes and obesity. The native hormones have pharmacological deficiencies such as short half-life and poor solubility. A novel glucagon receptor agonist named glucagon-Cex has been designed, synthesized and crystallized. This peptide was highly soluble under physiological conditions and crystallized readily. The crystal diffracted X-rays to 2.2 Å resolution and the diffraction was consistent with space group P23, with unit-cell parameters a = b = c = 48.20 Å, α = β = γ = 90.0°. The crystals were suitable for a full structural determination to reveal the conformational differences between glucagon-Cex and the native hormone.

  12. Synthesis and characterization of iron cobalt (FECO) nanorods ...

    African Journals Online (AJOL)

    Synthesis and characterization of iron cobalt (FECO) nanorods prepared by simple ... shaped by increasing annealing temperature from room temperature to 800 ... Keywords: FeCo nanoparticles, sodium borohydrid, CTAB, chemical synthesis ...

  13. Synthesis, characterization and anti-microbial activity of pure, Cu2+ and Cd2+ doped organic NLO l-arginine trifluoroacetate single crystals

    Science.gov (United States)

    Prasanyaa, T.; Haris, M.; Jayaramakrishnan, V.; Amgalan, M.; Mathivanan, V.

    2013-10-01

    Optically transparent Cu2+ and Cd2+ doped l-arginine trifluoroacetate (LATF) single crystals were grown from its aqueous solution using the slow solvent evaporation technique. The grown crystals were characterized by powder x-ray diffraction to confirm the monoclinic crystal structure. The percentage of transmittance measured using the ultraviolet-visible-near infrared spectrophotometer was found to be more than 80% for doped crystals. The functional group analysis of the grown crystals has been made by Fourier transform infrared spectroscopy. Thermogravimetric/differential thermal analysis was performed for the grown crystals. An atomic absorption study was carried out to determine the presence of Cu2+ and Cd2+. The hardness of the grown crystals was assessed and the results show a significant variation in the hardness value between the pure and doped LATF crystals. The second harmonic generation measurements show that Cu2+ doped LATF is 2.8 times greater and Cd2+ doped is 2.6 times greater than KDP. The anti-bacterial and anti-fungal activities of the title compound were performed using the disc diffusion method against standard bacteria Escherichia coli, Xanthomonas oryzae and against the fungus Aspergillus niger and Aspergillus flavus.

  14. Synthesis, characterization and anti-microbial activity of pure, Cu2+ and Cd2+ doped organic NLO l-arginine trifluoroacetate single crystals

    International Nuclear Information System (INIS)

    Prasanyaa, T; Haris, M; Amgalan, M; Mathivanan, V; Jayaramakrishnan, V

    2013-01-01

    Optically transparent Cu 2+ and Cd 2+ doped l-arginine trifluoroacetate (LATF) single crystals were grown from its aqueous solution using the slow solvent evaporation technique. The grown crystals were characterized by powder x-ray diffraction to confirm the monoclinic crystal structure. The percentage of transmittance measured using the ultraviolet–visible–near infrared spectrophotometer was found to be more than 80% for doped crystals. The functional group analysis of the grown crystals has been made by Fourier transform infrared spectroscopy. Thermogravimetric/differential thermal analysis was performed for the grown crystals. An atomic absorption study was carried out to determine the presence of Cu 2+ and Cd 2+ . The hardness of the grown crystals was assessed and the results show a significant variation in the hardness value between the pure and doped LATF crystals. The second harmonic generation measurements show that Cu 2+ doped LATF is 2.8 times greater and Cd 2+ doped is 2.6 times greater than KDP. The anti-bacterial and anti-fungal activities of the title compound were performed using the disc diffusion method against standard bacteria Escherichia coli, Xanthomonas oryzae and against the fungus Aspergillus niger and Aspergillus flavus. (paper)

  15. Synthesis and magnetic properties of SmOOH crystals

    Energy Technology Data Exchange (ETDEWEB)

    Samata, Hiroaki, E-mail: samata@maritime.kobe-u.ac.jp [Graduate School of Maritime Sciences, Kobe University, Fukaeminami, Higashinada, Kobe, Hyogo 658-0022 (Japan); Hanioka, Masashi [Graduate School of Maritime Sciences, Kobe University, Fukaeminami, Higashinada, Kobe, Hyogo 658-0022 (Japan); Ozawa, Tadashi C. [Materials Development Group, Superconducting Properties Unit, National Institute for Materials Science, Sengen, Tsukuba, Ibaraki 305-0047 (Japan)

    2016-01-15

    Samarium oxyhydroxide (SmOOH) crystals were synthesized using a flux method. The as-grown crystals were yellowish, transparent, and elongated with a maximum length of approximately 1.0 mm. SmOOH adopts a monoclinic structure in the space group P2{sub 1}/m with a=0.4356 nm, b=0.3766 nm, c=0.6139 nm, and β=108.464°. The magnetic susceptibility of the SmOOH crystals exhibited typical Van Vleck paramagnetism, and the experimental data at temperatures above 200 K were in close agreement with the calculated results using a spin-orbit coupling constant λ=443 K (308 cm{sup −1}). - Highlights: • SmOOH crystals were synthesized via flux method and characterized. • Magnetic susceptibilities above 200 K agreed with theoretical Van Vleck values. • Discrepancies were observed at lower temperatures based on the crystalline field.

  16. An unsymmetrical porphyrin and its metal complexes: synthesis, spectroscopy, thermal analysis and liquid crystal properties

    Directory of Open Access Journals (Sweden)

    CHANGFU ZHUANG

    2009-09-01

    Full Text Available The synthesis and characterization of a new unsymmetrical porphyrin liquid crystal, 5-(4-stearoyloxyphenylphenyl-10,15,20-triphenylporphyrin (SPTPPH2 and its transition metal complexes (SPTPPM, M(II = Zn, Fe, Co, Ni, Cu or Mn are reported. Their structure and properties were studied by elemental analysis, and UV–Vis, IR, mass and 1H-HMR spectroscopy. Their luminescent properties were studied by excitation and emission spectroscopy. The quantum yields of the S1 ® S0 fluorescence were measured at room temperature. According to thermal studies, the complexes have a higher thermal stability (no decomposition until 200 °C. Differential scanning calorimetry (DSC data and an optical textural photograph, obtained using a polarizing microscope (POM, indicate that the porphyrin ligand had liquid crystalline character and that it exhibited more than one mesophase and a low-lying phase transition temperature, with transition temperatures of 19.3 and 79.4 °C; the temperature range of the liquid crystal (LC phase of the ligand was 70.1 °C.

  17. Cultivation and characterization of GaInSe2 crystals

    International Nuclear Information System (INIS)

    Panakhov, T.M.; Kafarova, D.M.

    2013-01-01

    This work is the first systematic study devoted to the growth of GaInSe 2 crystals and their characterization by experimental methods such as X-ray diffraction, electron microscopy transmission with high resolution, sample electron diffraction. By the method of photoelectron roentgen spectroscopy it was studied the chemical structure of the GaInSe 2 crystals and the microprobe analysis indicated that the individual crystals have an excess of gallium. GaInSe 2 crystals were grown by the Bridgman method. Samples were prepared as single crystals by the Bridgman method. Studies showed that the GaInSe 2 crystals are hexagonal ones

  18. Hydrothermal synthesis and characterization of a two-dimensional piperazinium cobalt–zinc phosphate via a metastable one-dimensional phase

    International Nuclear Information System (INIS)

    Torre-Fernández, Laura; Khainakova, Olena A.; Espina, Aránzazu; Amghouz, Zakariae; Khainakov, Sergei A.; Alfonso, Belén F.; Blanco, Jesús A.; García, José R.; García-Granda, Santiago

    2015-01-01

    A two-dimensional piperazinium cobalt–zinc phosphate, formulated as (C 4 N 2 H 12 ) 1.5 (Co 0.6 Zn 0.4 ) 2 (HPO 4 ) 2 (PO 4 )·H 2 O (2D), was synthesized under hydrothermal conditions. The crystal structure was determined using single-crystal X-ray diffraction data (monoclinic P2 1 /c, a=8.1165(3) Å, b=26.2301(10) Å, c=8.3595(4) Å, and β=110.930(5)°) and the hydrogen atom positions were optimized by DFT calculations. A single-crystal corresponding to one-dimensional metastable phase, (C 4 N 2 H 12 )Co 0.3 Zn 0.7 (HPO 4 ) 2 ·H 2 O (1D), was also isolated and the crystal structure was determined (monoclinic P2 1 /c, a=8.9120(6) Å, b=14.0290(1) Å, c=12.2494(5) Å, and β=130.884(6)°). The bulk was characterized by chemical (C–H–N) analysis, powder X-ray diffraction (PXRD), powder X-ray thermodiffractometry (HT-XRD), transmission electron microscopy (STEM(DF)-EDX and EFTEM), and thermal analysis (TG/SDTA-MS), including activation energy data of its thermal decomposition. The magnetic susceptibility and magnetization measurements show no magnetic ordering down to 4 K. - Graphical abstract: Hydrothermal synthesis and structural characterization of a two-dimensional piperazinium cobalt–zinc phosphate, (C 4 N 2 H 12 ) 1.5 (Co 0.6 Zn 0.4 ) 2 (HPO 4 ) 2 (PO 4 )·H 2 O (2D), have been reported. The crystal structure of a one-dimensional piperazinium cobalt–zinc phosphate, (C 4 N 2 H 12 )Co 0.3 Zn 0.7 (HPO 4 ) 2 ·H 2 O (1D) a metastable phase during the hydrothermal synthesis, was also determined. The thermal behavior of 2D compound is strongly dependent on the selected heating rate and the magnetic susceptibility and magnetization measurements show no magnetic ordering down to 4 K. - Highlights: • A 2D piperazinium cobalt–zinc phosphate has been synthesized and characterized. • Crystal structure of 1D metastable phase was also determined. • Thermal behavior of 2D compound is strongly dependent on the selected heating rate. • Magnetic

  19. A microporous potassium vanadyl phosphate analogue of mahnertite. Hydrothermal synthesis and crystal structure

    International Nuclear Information System (INIS)

    Yakubovich, Olga V.; Russian Academy of Science, Moscow; Steele, Ian M.; Kiriukhina, Galina V.; Dimitrova, Olga V.

    2015-01-01

    The novel phase K 2.5 Cu 5 Cl(PO 4 ) 4 (OH) 0.5 (VO 2 ).H 2 O was prepared by hydrothermal synthesis at 553 K. Its crystal structure was determined using low-temperature (100 K) single-crystal synchrotron diffraction data and refined against F 2 to R = 0.035. The compound crystallizes in the tetragonal space group I4/mmm, with unit-cell parameters a =9.8120(8), c = 19.954(1) Aa, V = 1921.1(2) Aa 3 , and Z = 4. Both symmetrically independent Cu 2+ sites show elongated square-pyramidal coordination. The V 5+ ions reside in strongly distorted five-vertex VO 5 polyhedra with 50% occupancy. The structure is based on a 3D anionic framework built from Cu- and V-centered five-vertex polyhedra and PO 4 tetrahedra. Channels in the [100] and [010] directions accommodate large K atoms and H 2 O molecules. The compound is a new structural representative of the topology shown by the lavendulan group of copper arsenate and phosphate minerals. Their tetragonal or pseudotetragonal crystal structures are characterized by two types of 2D slabs alternating along one axis of their unit cells. One slab, described by the formula [Cu 4 X(TO 4 ) 4 ] 8 (where X = Cl, O and T = As, P), is common to all phases, whereas the slab content of the other set differs among the group members. We suggest interpreting this family of compounds in terms of the modular concept and also consider the synthetic phase Ba(VO)Cu 4 (PO 4 ) 4 as a simplest member of this polysomatic series.

  20. Synthesis and Characterization of Birnessite and Cryptomelane Nanostructures in Presence of Hoffmeister Anions

    Directory of Open Access Journals (Sweden)

    Marcos A. Cheney

    2009-01-01

    Full Text Available The effect of Hoffmeister anions Cl−, SO42−, and ClO4− on the structure and morphology of birnessite and cryptomelane-type manganese dioxide nanostructures, produced by the reduction reaction of KMnO4 and MnSO4 in aqueous acidic media, was studied. The syntheses were based on the decomposition of aqueous KMnO4 in presence of HCl for birnessite-type and acidified MnSO4 for cryptomelane-type manganese dioxide under soft hydrothermal conditions. They were characterized using X-ray diffraction (XRD, transmission electron microscopy (TEM, and high-resolution transmission electron microscopy (HRTEM techniques. XRD patterns show the formation of birnessite for the first synthesis and a mixture of cryptomelane and birnessite-types MnO2 for the second synthesis. XRD data revealed that the Hoffmeister anions have a significant effect on the nanostructures of birnessite. The sulphate ion-treated birnessite has the smallest crystals, whereas the chloride ion-treated birnessite has the largest crystals. Their TEM and HRTEM studies revealed a transformation from nanoplatelet morphology for chloride-treated samples to nanofibrous morphology for sulphate-treated birnessite. For the cryptomelane nanostructures, Hoffmeister anions also show a profound effect on their crystalline structures as determined by XRD analyses revealing a transformation of the cryptomelane phase to birnessite phase of MnO2. This transformation is also supported by TEM and HRTEM studies.

  1. Synthesis, growth, morphology of the semiorganic nonlinear optical crystal L-glutamic acid hydrochloride and its structural, thermal and SHG characterizations

    Energy Technology Data Exchange (ETDEWEB)

    Dhanasekaran, P.; Srinivasan, K. [Crystal Growth Laboratory, Department of Physics, School of Physical Sciences, Bharathiar University, Coimbatore-641 046, Tamil Nadu (India)

    2012-12-15

    One of the halide derivatives of L-glutamic acid which was identified as a semiorganic nonlinear optical material, L-glutamic acid hydrochloride [HOOC(CH{sub 2}){sub 2}CH(NH{sub 2})COOH.HCl], was grown as bulk single crystal and its significant properties were characterized. The stoichiometric title compound was synthesized and the solubility of its recrystallized form in DD water was determined in the temperature range 30-80 C by gravimetric method. Structural confirmation was carried out by powder X-ray diffraction study through lattice parameter verification. Optical quality smaller dimension single crystals were grown from aqueous solution by self nucleation through slow evaporation of solvent method and a large dimension single crystal was grown by slow cooling method with reversible seed rotation technique. Morphological importances of different growth facets of the as grown crystals were studied through optical goniometry. Unit cell structure of the grown crystal was refined by single crystal X-ray diffraction analysis, functional groups present in the crystal responsible for various modes of vibrations were confirmed by FTIR spectroscopy analysis, thermal stability of the grown crystal was analysed by TG/DTA and DSC and second harmonic generation (SHG) of a fundamental Nd:YAG laser beam by Kurtz technique. Results indicate that the grown crystal is in stoichiometric composition and has significant improvement in its thermal and SHG properties when compared to pure L-glutamic acid polymorphs. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  2. Synthesis, crystal structures and properties of new quinolinium derivatives

    Science.gov (United States)

    Zhang, Xinyuan; Jiang, Xingxing; Li, Yin; Lin, Zheshuai; Zhang, Guochun; Wu, Yicheng

    2015-11-01

    Four phenyl-substituted quinolinium salts with different counter anions, C27H27NO4S, C26H25NO5S, C25H22NO5SCl, and C25H22NO5SBr, were synthesized and their single crystals were successfully grown from methanol solution by slow evaporation. Single crystal X-ray diffraction analyses showed that C27H27NO4S crystal belongs to the noncentrosymmetric orthorhombic space group Pna21, and the other three crystals belong to centrosymmetric monoclinic space group P21/n. Their first order hyperpolarization and macroscopic nonlinearity were analyzed and physical properties were characterized by UV-vis absorption spectroscopy, and differential scanning calorimetric and thermal gravimetric analysis.

  3. Tuned apatitic materials: Synthesis, characterization and potential antimicrobial applications

    Science.gov (United States)

    Fierascu, Irina; Fierascu, Radu Claudiu; Somoghi, Raluca; Ion, Rodica Mariana; Moanta, Adriana; Avramescu, Sorin Marius; Damian, Celina Maria; Ditu, Lia Mara

    2018-04-01

    Inorganic antimicrobial materials can be viable for multiple applications (related to its use for new buildings with special requirements related to microbiological loading, such as hospital buildings and for consolidation of cultural heritage constructions); also the use of substituted hydroxyapatites for protection of stone artefacts against environmental factors (acidic rain) and biodeterioration it's an option to no longer use of toxic substances. This paper presents methods of synthesis and characterization of the material from the point of view of the obtained structures and final applications. The materials were characterized in terms of composition and morphology (using X-ray Diffraction, X-ray Fluorescence, Inductively coupled plasma-atomic emission spectrometry, Fourier Transform Infrared Spectroscopy, X-ray Photoelectron Spectroscopy, Surface area and pore size determination). Antimicrobial activity was tested against filamentous fungi strains and pathogenic bacteria strains, using both spot on lawn qualitative method (on agar medium) and serial microdilution quantitative method (in broth medium). Further, it was evaluated the anti-biofilm activity of the tested samples toward the most important microbial strains implicated in biofilm development, using crystal violet stained biofilms microtiter assay, followed by spectrophotometric quantitative evaluation.

  4. Synthesis, Characterization and Application of Multiscale Porous Materials

    Energy Technology Data Exchange (ETDEWEB)

    Hussami, Linda

    2010-07-01

    This thesis work brings fresh insights and improved understanding of nano scale materials through introducing new hybrid composites, 2D hexagonal in MCM-41 and 3D random interconnected structures of different materials, and application relevance for developing fields of science, such as fuel cells and solar cells. New types of porous materials and organometallic crystals have been prepared and characterized in detail. The porous materials have been used in several studies: as hosts to encapsulate metal-organic complexes; as catalyst supports and electrode materials in devices for alternative energy production. The utility of the new porous materials arises from their unique structural and surface chemical characteristics as demonstrated here using various experimental and theoretical approaches. New single crystal structures and arene-ligand exchange properties of f-block elements coordinated to ligand arene and halogallates are described in Paper I. These compounds have been incorporated into ordered 2D-hexagonal MCM-41 and polyhedral silica nano foam (PNF-SiO{sub 2}) matrices without significant change to the original porous architectures as described in Paper II and III. The resulting inorganic/organic hybrids exhibited enhanced luminescence activity relative to the pure crystalline complexes. A series of novel polyhedral carbon nano foams (PNF-C's) and inverse foams were prepared by nano casting from PNF-SiO{sub 2}'s. These are discussed in Paper IV. The synthesis conditions of PNF-C's were systematically varied as a function of the filling ratio of carbon precursor and their structures compared using various characterization methods. The carbonaceous porous materials were further tested in Paper V and VI as possible catalysts and catalyst supports in counter- and working electrodes for solar- and fuel cell applications

  5. Characterization and crystal structures of new Schiff base macrocyclic compounds

    Czech Academy of Sciences Publication Activity Database

    Khalaji, A.D.; Ghoran, S.H.; Pojarová, Michaela; Dušek, Michal

    2015-01-01

    Roč. 56, č. 7 (2015), s. 1410-1414 ISSN 0022-4766 R&D Projects: GA ČR(CZ) GA14-03276S Institutional support: RVO:68378271 Keywords : synthesis * macrocyclic Schiff base * single crystal structure analysis * spectroscopy Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 0.536, year: 2015

  6. Synthesis, crystal growth, structural and physicochemical studies of novel binary organic complex: 4-chloroaniline–3-hydroxy-4-methoxybenzaldehyde

    International Nuclear Information System (INIS)

    Sharma, K.P.; Reddi, R.S.B.; Bhattacharya, S.; Rai, R.N.

    2012-01-01

    The solid-state reaction, which is solvent free and green synthesis, has been adopted to explore the novel compound. The phase diagram of 4-chloroaniline (CA) and 3-hydroxy-4-methoxybenzaldehyde (HMB) system shows the formation of a novel 1:1 molecular complex, and two eutectics on either sides of complex. Thermochemical studies of complex and eutectics have been carried out for various properties such as heat of fusion, entropy of fusion, Jackson's parameters, interfacial energy and excess thermodynamic functions. The formation of molecular complex was also studied by IR, NMR, elemental analysis and UV–Vis absorption spectra. The single crystal of molecular complex was grown and its XRD study confirms the formation of complex and identifies the crystal structure and atomic packing of crystal of complex. Transmission spectra of grown crystal of the complex show 70% transmittance efficiency with cut off wavelength 412 nm. The band gap and refractive index of the crystal of complex have also been studied. - Graphical abstarct: Exploiting phase diagram study and solvent free synthesis a novel compound was synthesized and its single crystal growth, atomic packing, energy band gap and refractive index were studied. Highlights: ► Novel organic complex was synthesized using Green or solvent free synthesis. ► Phase diagram study provided the information to identify the worthy composition of novel complex. ► The single crystal of the sufficient size was grown from the ethanol solution. ► Crystal analysis suggested that the covalent bond is formed between the two parent compounds. ► The transmittance of the crystal was found to be 70% and it was transparent from 412 to 850 nm.

  7. Synthesis and characterization of zeolite P using technical-grade materials

    CERN Document Server

    Aghabozorg, H R; Aghabozorg, H R; Sharif, M

    2001-01-01

    Research attempts on zeolites show structural and industrial importance of these inorganic compounds. In this regard, the synthesis of zeolites is of great importance, because their natural occurring counterparts are often impure. Zeolite Na-P with a silicon to aluminium ratio of one has a better ion exchange capacity than Na-A and can be used as a detergent builder. In this work, zeolite Na-P of high purity was successfully synthesized using commercial silica and alumina sources. parameters such as H sub 2 O:A1 sub 2 O sub 3 and SiO sub 2 :A1 sub 2 O sub 3 molar ratios and crystallization temperature and time were investigated. So that the optimum condition was obtained. X-ray powder diffraction, infrared, scanning electron microscopy and elemental analysis were utilized for the characterization of the product.

  8. Metal-organic frameworks: structure, properties, methods of synthesis and characterization

    International Nuclear Information System (INIS)

    Butova, V V; Soldatov, M A; Guda, A A; Lomachenko, K A; Lamberti, C

    2016-01-01

    This review deals with key methods of synthesis and characterization of metal-organic frameworks (MOFs). The modular structure affords a wide variety of MOFs with different active metal sites and organic linkers. These compounds represent a new stage of development of porous materials in which the pore size and the active site structure can be modified within wide limits. The set of experimental methods considered in this review is sufficient for studying the short-range and long-range order of the MOF crystal structure, determining the morphology of samples and elucidating the processes that occur at the active metal site in the course of chemical reactions. The interest in metal-organic frameworks results, first of all, from their numerous possible applications, ranging from gas separation and storage to chemical reactions within the pores. The bibliography includes 362 references

  9. Hydrothermal synthesis, characterization and luminescent ...

    Indian Academy of Sciences (India)

    Home; Journals; Bulletin of Materials Science; Volume 39; Issue 4. Hydrothermal synthesis, characterization and luminescent properties of lanthanide-doped NaLaF 4 nanoparticles. JIGMET LADOL HEENA KHAJURIA SONIKA KHAJURIA ... Keywords. Citric acid; X-ray diffraction; down-conversion emission; energy transfer.

  10. Synthesis, stability range and characterization of Pr2Cu2O5

    Science.gov (United States)

    Fernández-Sanjulián, Javier; Morán, Emilio; Ángel Alario-Franco, Miguel

    2010-03-01

    A novel Pr2Cu2O5 phase has been prepared under high-pressure and high-temperature conditions (P ∼6 GPa and T ∼1673 K) in a Belt-type apparatus and characterized by X-ray diffraction and electron microscopy. The crystal structure appears to be an orthorhombic "oxygen-deficient perovskite" (M.T. Anderson, J.T. Vaughey, and K.R. Poeppelmeier, Structural similarities among oxygen-deficient perovskites, Chem. Mater. 5 (1993), pp. 151-165) isostructural with La2Cu2O5 (J.F. Bringley, B.A. Scott, S.J. La Placa, R.F. Boheme, T.M. Shaw, M.W. McElfresh, S.S. Trail, and D.E. Cox, Synthesis of the defect perovskite series LaCuO 3-δ with copper valence varying from 2+to 3+, Nature 347 (1990), pp. 263-265) and Nd2Cu2O5 (B.-H. Chen, D. Walker, E. Suard, B.A. Scott, B. Mercey, M. Hervieu, and B. Raveau, High pressure synthesis of NdCuO3-δ perovskites (0≤δ≤0.5). Inorg. Chem. 34 (1995), pp. 2077-2083).

  11. Synthesis and structural characterization of Na 2 MnP 2 O 7 crystal

    Indian Academy of Sciences (India)

    Na2MnP2O7 crystals were synthesized by hydrothermal technique. Crystals obtained are in the form of single crystals of rhombohedral morphology with lattice parameters as follows: triclinic, 1 ¯ , = 0.71069 Å, = 6.657(3) Å, = 6.714(6) Å, = 6.518(4) Å, = 112.31(6)°, = 92.14(4)°, = 83.89(5)°, = 268.0(3) Å3, ...

  12. Synthesis and physicochemical characterizations and antimicrobial activity of ZnO nanoparticles

    Science.gov (United States)

    Sharma, Bhumika K.; Patel, Kinjal; Roy, Debesh R.

    2018-05-01

    Nanoparticles exhibit very interesting and useful physicochemical properties when they interact with substrates and goes through some physicochemical and/or biological processes. ZnO is known to be a highly demanding nanomaterial due to its discreet properties, shapes and sizes. A detail experimental study on the synthesis, characterization and antibacterial activity of ZnO nanoparticles (NPs) is performed. ZnO NPs are synthesized using chemical precipitation method. The understanding of crystal structure, morphology and elemental compositions are explained using Powder X-Ray Diffraction (XRD) and Field Emission Scanning Electron Microscope (FE-SEM) respectively. Fourier transform infrared spectroscopy (FTIR) is performed to achieve the information on the presence of various functional groups. The antibacterial activity of these ZnO NPs is investigated in terms of Zone of Inhibition (ZOI) against Escherichia coli (Gram negative) microorganisms.

  13. Synthesis and characterization of the ternary telluroargentate K4[Ag18Te11

    KAUST Repository

    Davaasuren, Bambar; Dashjav, Enkhtsetseg; Rothenberger, Alexander

    2014-01-01

    The ternary potassium telluroargentate(I), K4[Ag18Te11], was prepared by solvothermal synthesis in ethylenediamine at 160 °C. It crystallizes in the cubic space group Fm3¯ m (no. 225) with the cell parameter a = 18.6589(6) Å. The crystal structure

  14. Synthesis, crystal growth, structural and physicochemical studies of novel binary organic complex: 4-chloroaniline-3-hydroxy-4-methoxybenzaldehyde

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, K.P.; Reddi, R.S.B.; Bhattacharya, S. [Department of Chemistry, Centre of Advance Study, Banaras Hindu University, Varanasi-221005 (India); Rai, R.N., E-mail: rn_rai@yahoo.co.in [Department of Chemistry, Centre of Advance Study, Banaras Hindu University, Varanasi-221005 (India)

    2012-06-15

    The solid-state reaction, which is solvent free and green synthesis, has been adopted to explore the novel compound. The phase diagram of 4-chloroaniline (CA) and 3-hydroxy-4-methoxybenzaldehyde (HMB) system shows the formation of a novel 1:1 molecular complex, and two eutectics on either sides of complex. Thermochemical studies of complex and eutectics have been carried out for various properties such as heat of fusion, entropy of fusion, Jackson's parameters, interfacial energy and excess thermodynamic functions. The formation of molecular complex was also studied by IR, NMR, elemental analysis and UV-Vis absorption spectra. The single crystal of molecular complex was grown and its XRD study confirms the formation of complex and identifies the crystal structure and atomic packing of crystal of complex. Transmission spectra of grown crystal of the complex show 70% transmittance efficiency with cut off wavelength 412 nm. The band gap and refractive index of the crystal of complex have also been studied. - Graphical abstarct: Exploiting phase diagram study and solvent free synthesis a novel compound was synthesized and its single crystal growth, atomic packing, energy band gap and refractive index were studied. Highlights: Black-Right-Pointing-Pointer Novel organic complex was synthesized using Green or solvent free synthesis. Black-Right-Pointing-Pointer Phase diagram study provided the information to identify the worthy composition of novel complex. Black-Right-Pointing-Pointer The single crystal of the sufficient size was grown from the ethanol solution. Black-Right-Pointing-Pointer Crystal analysis suggested that the covalent bond is formed between the two parent compounds. Black-Right-Pointing-Pointer The transmittance of the crystal was found to be 70% and it was transparent from 412 to 850 nm.

  15. Synthesis and characterization of CuGeO3 photocatalyst using Green Chemistry and its application for the degradation of direct black dye

    Directory of Open Access Journals (Sweden)

    Ashok. V. Borhade

    2013-03-01

    Full Text Available In this paper, we report synthesis of CuGeO3 photocatalyst by mechanochemical, solid state synthesis, method with green chemistry approach. The product obtained was characterized by various investigative techniques like UV-Diffuse Reflectance Spectroscopy, Fourier Transform Infrared Spectroscopy, X-ray Diffraction, Scanning Electron Microscopy, with Energy Dispersive X-ray Spectroscopy, and BET Surface area. The study confirm orthorhombic pervoskite crystal structure of photocatalyst with band gap 3.7 eV. The photocatalytic activity of the catalysts CuGeO3 was evaluated by photochemical bleaching of Direct black dye, under sun light.

  16. Synthesis of guanidinium–sulfonimide ion pairs: towards novel ionic liquid crystals

    Directory of Open Access Journals (Sweden)

    Martin Butschies

    2013-06-01

    Full Text Available The recently introduced concept of ionic liquid crystals (ILCs with complementary ion pairs, consisting of both, mesogenic cation and anion, was extended from guanidinium sulfonates to guanidinium sulfonimides. In this preliminary study, the synthesis and mesomorphic properties of selected derivatives were described, which provide the first example of an ILC with the sulfonimide anion directly attached to the mesogenic unit.

  17. Synthesis and characterization of LiFePO{sub 4} cathode preparation by low temperature method

    Energy Technology Data Exchange (ETDEWEB)

    Rajesh, Desapogu, E-mail: rajesh.desapogu@gmail.com; Srinivas Naik, V.; Sunandana, C.S., E-mail: sunandana@gmail.com

    2015-05-01

    We review in detail the physics and technology of the novel material LiFePO{sub 4}, a potential cathode material for Li-ion batteries. In the present work, nano crystalline LiFePO{sub 4} film has been synthesized in both powder and thin film forms from a non-aqueous sol–gel synthesis route based on oxalates of Li and Fe (II). Ferrous oxalate has been synthesized indigenously using a ferrous sulphate based chemical reaction and characterized. Nano powders and thin films of LiFePO{sub 4} have been fabricated and coated on stainless steel substrates with the aim of device development in future. The material has been characterized extensively by XRD for crystal structure, FESEM for microstructure, EDS for elemental analysis and FTIR for the internal modes of phosphate ion. Fe{sup 3+} impurity characterization has been done by using ESR.

  18. A microporous potassium vanadyl phosphate analogue of mahnertite. Hydrothermal synthesis and crystal structure

    Energy Technology Data Exchange (ETDEWEB)

    Yakubovich, Olga V. [M.V. Lomonosov Moscow State Univ. (Russian Federation). Dept. of Crystallography; Russian Academy of Science, Moscow (Russian Federation). Inst. of Geology of Deposits, Petrography, Mineralogy and Geochemistry; Steele, Ian M. [Notre Dame Univ., IN (United States). Notre Dame Integrated Imaging Facility; Kiriukhina, Galina V.; Dimitrova, Olga V. [M.V. Lomonosov Moscow State Univ. (Russian Federation). Dept. of Crystallography

    2015-09-01

    The novel phase K{sub 2.5}Cu{sub 5}Cl(PO{sub 4}){sub 4}(OH){sub 0.5}(VO{sub 2}).H{sub 2}O was prepared by hydrothermal synthesis at 553 K. Its crystal structure was determined using low-temperature (100 K) single-crystal synchrotron diffraction data and refined against F{sup 2} to R = 0.035. The compound crystallizes in the tetragonal space group I4/mmm, with unit-cell parameters a =9.8120(8), c = 19.954(1) Aa, V = 1921.1(2) Aa{sup 3}, and Z = 4. Both symmetrically independent Cu{sup 2+} sites show elongated square-pyramidal coordination. The V{sup 5+} ions reside in strongly distorted five-vertex VO{sub 5} polyhedra with 50% occupancy. The structure is based on a 3D anionic framework built from Cu- and V-centered five-vertex polyhedra and PO{sub 4} tetrahedra. Channels in the [100] and [010] directions accommodate large K atoms and H{sub 2}O molecules. The compound is a new structural representative of the topology shown by the lavendulan group of copper arsenate and phosphate minerals. Their tetragonal or pseudotetragonal crystal structures are characterized by two types of 2D slabs alternating along one axis of their unit cells. One slab, described by the formula [Cu{sub 4}X(TO{sub 4}){sub 4}]{sub 8} (where X = Cl, O and T = As, P), is common to all phases, whereas the slab content of the other set differs among the group members. We suggest interpreting this family of compounds in terms of the modular concept and also consider the synthetic phase Ba(VO)Cu{sub 4}(PO{sub 4}){sub 4} as a simplest member of this polysomatic series.

  19. Structural and Biochemical Characterization of Chlamydia trachomatis Hypothetical Protein CT263 Supports That Menaquinone Synthesis Occurs through the Futalosine Pathway*

    Science.gov (United States)

    Barta, Michael L.; Thomas, Keisha; Yuan, Hongling; Lovell, Scott; Battaile, Kevin P.; Schramm, Vern L.; Hefty, P. Scott

    2014-01-01

    The obligate intracellular human pathogen Chlamydia trachomatis is the etiological agent of blinding trachoma and sexually transmitted disease. Genomic sequencing of Chlamydia indicated this medically important bacterium was not exclusively dependent on the host cell for energy. In order for the electron transport chain to function, electron shuttling between membrane-embedded complexes requires lipid-soluble quinones (e.g. menaquionone or ubiquinone). The sources or biosynthetic pathways required to obtain these electron carriers within C. trachomatis are poorly understood. The 1.58Å crystal structure of C. trachomatis hypothetical protein CT263 presented here supports a role in quinone biosynthesis. Although CT263 lacks sequence-based functional annotation, the crystal structure of CT263 displays striking structural similarity to 5′-methylthioadenosine nucleosidase (MTAN) enzymes. Although CT263 lacks the active site-associated dimer interface found in prototypical MTANs, co-crystal structures with product (adenine) or substrate (5′-methylthioadenosine) indicate that the canonical active site residues are conserved. Enzymatic characterization of CT263 indicates that the futalosine pathway intermediate 6-amino-6-deoxyfutalosine (kcat/Km = 1.8 × 103 m−1 s−1), but not the prototypical MTAN substrates (e.g. S-adenosylhomocysteine and 5′-methylthioadenosine), is hydrolyzed. Bioinformatic analyses of the chlamydial proteome also support the futalosine pathway toward the synthesis of menaquinone in Chlamydiaceae. This report provides the first experimental support for quinone synthesis in Chlamydia. Menaquinone synthesis provides another target for agents to combat C. trachomatis infection. PMID:25253688

  20. 129Xe-NMR study of the crystallization of SAPO-37

    International Nuclear Information System (INIS)

    Ito, T.; Dumont, N.; Nagy, J.B.; Gabelica, Z.; Derouane, E.G.

    1991-01-01

    The different stages of SAPO-37 crystallization have been characterized by NMR of 129 Xe adsorbed on a series of intermediate phases isolated during synthesis. The nucleation of SAPO-37 occurs within the amorphous phase; the gel then undergoes a preliminary structuration through the formation of large cavities during the aging period. Upon heating at 200 deg C, the gel transforms into well-defined crystals of SAPO-37. The crystallinity increases with the synthesis time and reaches a maximum after 32h. For longer synthesis times, a crystalline side-phase, SAPO-40, develops in the liquid phase. SAPO-40 has a narrower pore structure than SAPO-37, possibly limited by 12 T puckered rings. (author). 20 refs.; 4 figs.; 1 tab

  1. CsPb2Br5 Single Crystals: Synthesis and Characterization

    KAUST Repository

    Dursun, Ibrahim; de Bastiani, Michele; Turedi, Bekir; Alamer, Badriah Jaber; Shkurenko, Aleksander; Yin, Jun; Gereige, Issam; Alsaggaf, Ahmed; Mohammed, Omar F.; Eddaoudi, Mohamed; Bakr, Osman

    2017-01-01

    , which enabled us to finally clarify the material's optical features. Our CsPb2Br5 crystal has a two-dimensional structure with Pb2Br5- layers spaced by Cs+ cations, and exhibits a ~3.1 eV indirect bandgap with no emission in the visible spectrum.

  2. From computational discovery to experimental characterization of a high hole mobility organic crystal.

    KAUST Repository

    Sokolov, Anatoliy N

    2011-08-16

    For organic semiconductors to find ubiquitous electronics applications, the development of new materials with high mobility and air stability is critical. Despite the versatility of carbon, exploratory chemical synthesis in the vast chemical space can be hindered by synthetic and characterization difficulties. Here we show that in silico screening of novel derivatives of the dinaphtho[2,3-b:2\\',3\\'-f]thieno[3,2-b]thiophene semiconductor with high hole mobility and air stability can lead to the discovery of a new high-performance semiconductor. On the basis of estimates from the Marcus theory of charge transfer rates, we identified a novel compound expected to demonstrate a theoretic twofold improvement in mobility over the parent molecule. Synthetic and electrical characterization of the compound is reported with single-crystal field-effect transistors, showing a remarkable saturation and linear mobility of 12.3 and 16 cm(2) V(-1) s(-1), respectively. This is one of the very few organic semiconductors with mobility greater than 10 cm(2) V(-1) s(-1) reported to date.

  3. Synthesis and characterization of some complexes with imidazole and pyrazole from saccharinate transition ions in oxidation state (II)

    International Nuclear Information System (INIS)

    Pineda Cedeno, Leslie William

    2001-01-01

    The synthesis and characterization of metal ions saccharinate of the first serie of transition with the imidazole and pyrazole molecules in water and absolute ethanol were studied. In general, it found that in this series of saccharinate of coordinated water molecules are replaced by imidazole and pyrazole molecules with different substitution patterns, generating neutral complex of molecular formula [M(Sac) 2 (L) n (H 2 O) n-4 ] and cationic complex of molecular formula [M(L) n (H 2 O) 2 ]x2Sac, [M(L) n (H 2 O) 3 ]x2Sac, [M(L) n ]x2Sac, where M = V(II), Cr(II), Mc(II), Fe(II), Co(II), Ni(II) y Zn(II); Sac = saccharinate ion; L = imidazole (imd) and pyrazole (pir) and n = 6,4,3 and 2. These compounds are soluble in DMF and insoluble in all other common solvents. In turn, synthesized compounds in water were characterized by X ray crystallography, where preliminary data of refinement cycles, generate formulas of isostructural type [M(imd) 4 (H 2 O) 2 ]x2Sac and [M(Sac) 2 (pir) 2 (H 2 O) 2 ] where M = Co(II), Ni(II). The imidazole complex crystallize in the triclinic crystal system and space group P-1, while the pyrazole complexes crystallize in the monoclinic crystal system and space group P2 (1)/n. Gradual diminution was observed in the bond distances of M-N (saccharinate ion), M-N (imidazole) and M-N (pyrazole). The complex was characterized by spectroscopic methods, magnetic and electrochemical. (author) [es

  4. Synthesis, characterization, and crystal structures of diruthenium complexes containing bridging salicylato ligands

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Mingxuan; Yau, Chun Huan; Hu, Yuxin; Tan, Yong Leng Kelvin [Hwa Chong Institution (Singapore); Li, Yingzhou; Ganguly, Rakesh; Leong, Weng Kee [Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University (Singapore)

    2017-08-03

    The thermal reaction of Ru{sub 3}(CO){sub 12} (1) with salicylic acid, in the presence of triphenylphosphine, pyridine, or dimethylsulfoxide, afforded the dinuclear complexes Ru{sub 2}(CO){sub 4}(μ-O{sub 2}CC{sub 6}H{sub 4}OH){sub 2}L{sub 2} (2) [L = PPh{sub 3} (2a). C{sub 5}H{sub 5}N (2b); (CH{sub 3}){sub 2}SO (2c)]. Complex 2b was further reacted with the aromatic dimmines 2,2'-dipyridine or 1,10-phenanthroline to give the cationic diruthenium complexes [Ru{sub 2}(CO){sub 2}(μ-CO){sub 2}(μ-O{sub 2}CC{sub 6}H{sub 4}OH)(N intersection N){sub 2}]{sup +} (3) [(N intersection N) = 2,2'-dipyridine (3a); 1,10-phenanthroline (3b)], which were isolated as their tetraphenylborate salts. All five novel complexes were characterized spectroscopically and analytically. For 2a-2b and 3a-3b, single-crystal X-ray diffraction studies were also carried out. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  5. Synthesis and characterization of L-tyrosine hydrochloride crystals submitted to high and low temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Santos, C.A.A.S.; Facanha Filho, P.F.; Ribeiro, L.H.L.; Victor, F.M.S.; Abreu, D.C.; Santos, A.O. dos; Carvalho, J.O.; Soares, R.A.; Sousa, J.C.F.; Lima, R.C.; Cavaignac, A.O. [Universidade Federal do Maranhao (UFMA), MA (Brazil)

    2016-07-01

    Full text: New materials are emerging and generate advances in nonlinear optics that studies the phenomena related to changes in optical properties when occurs interaction of light with the matter. Semi organic crystals present such properties. The goal is this work is to produce semi organic single crystal of L-tyrosine hydrochloride (LTHCl) and verify their thermal stability when subjected to high and low temperatures. The single crystals of LTHCl were produced for solubilization of amino acid L-tyrosine in hydrochloric acid using slow solvent evaporation technique at a constant temperature of 25 deg C. The X-ray diffraction (XRD) and refining by the Rietveld method were used to confirm the structure of the material. The thermal stability was investigated using DSC, TGA-DTA. The LTHCl crystal belongs to the monoclinic system, with two molecules per unit cell. The refinement by the Rietveld method showed good results with Rwp= 8.49% and Rp= 6.29% with S=1.13. Thermal analysis shown an endothermic event at about 160°C, which can be associated with phase transition occurred in LTHCl crystal. It was also observed that the crystal melting point occurs at a temperature of 230°C. No water of crystallization was found in the crystal structure, which was confirmed by Raman spectroscopy and thermal analysis. From the Raman spectroscopy experiments in function of temperature, no significant changes was observe in the behavior of vibrational normal modes between temperatures of -253 and 170 deg C. Finally, a monoclinic crystal system LTHCl is stable up to 160°C at high temperatures and -253°C at low temperatures. Therefore, our investigation has proved that LTHCl crystals can be used in this range of temperature without the lost of their nonlinear optical properties. (author)

  6. Mesoporous MEL, BEA, and FAU zeolite crystals obtained by in situ formation of carbon template over metal nanoparticles

    DEFF Research Database (Denmark)

    Abildstrøm, Jacob Oskar; Ali, Zahra Nasrudin; Mentzel, Uffe Vie

    2016-01-01

    Here, we report the synthesis and characterization of hierarchical zeolite materials with MEL, BEA and FAU structures. The synthesis is based on the carbon templating method with an in situ-generated carbon template. Through the decomposition of methane and deposition of coke over nickel nanopart......Here, we report the synthesis and characterization of hierarchical zeolite materials with MEL, BEA and FAU structures. The synthesis is based on the carbon templating method with an in situ-generated carbon template. Through the decomposition of methane and deposition of coke over nickel...... nanoparticles supported on silica, a carbon–silica composite is obtained and exploited as a combined carbon template/silica source for the zeolite synthesis. The mesoporous zeolite materials were all prepared by hydrothermal crystallization in alkaline media followed by removal of the carbon template...... by combustion, which results in zeolite single crystals with intracrystalline pore volumes of up to 0.44 cm3 g−1. The prepared zeolite structures are characterized by XRD, SEM, TEM and N2 physisorption measurements....

  7. Synthesis, characterization, crystal structure and quantum chemical investigations of three novel coumarin-benzenesulfonohydrazide derivatives

    Science.gov (United States)

    Chethan Prathap, K. N.; Lokanath, N. K.

    2018-04-01

    Coumarin derivatives are an important class of heterocyclic compounds due to their physical and biological properties. Coumarin derivatives have been identified with many significant electro-optical properties and biological activities. Three novel coumarin derivatives containing benzene sulfonohydrazide group were synthesized by condensation reaction. The synthesized compounds were characterized by various spectroscopic techniques (Mass, 1H/13C NMR and FTIR). Thermal and optical properties were investigated by thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and UV-Vis spectroscopic studies. Finally their structures were confirmed by single crystal X-ray diffraction (XRD) studies. The three compounds exhibit diverse intermolecular interactions, as observed by the crystal packing and Hirshfeld surface analysis. Further, their structures were optimized by density functional theory (DFT) calculations using B3LYP hybrid functionals with 6-311G+(d,p) level basis set. The Mulliken charge, molecular electrostatic potential (MEP), frontier molecular orbitals (HOMO-LUMO) were investigated. The experimentally determined parameters were compared with those calculated theoretically and they complement each other with a very good correlation. The transitions among the molecular orbitals were investigated using time-dependent density functional theory (TD-DFT) and the electronic absorption spectra obtained showed very good agreement with the experimentally measured UV-Vis spectra. Furthermore, non-linear optical (NLO) properties were investigated by calculating polarizabilities and hyperpolarizabilities. All three compounds exhibit significantly high hyperpolarizabilities compared to the reference material urea, which makes them potential candidates for NLO applications.

  8. Hydrothermal synthesis and characterization of a two-dimensional piperazinium cobalt–zinc phosphate via a metastable one-dimensional phase

    Energy Technology Data Exchange (ETDEWEB)

    Torre-Fernández, Laura; Khainakova, Olena A. [Departamentos de Química Física y Analítica y Química Orgánica e Inorgánica, Universidad de Oviedo-CINN, 33006 Oviedo (Spain); Espina, Aránzazu [Servicios Científico Técnicos, Universidad de Oviedo, 33006 Oviedo (Spain); Amghouz, Zakariae, E-mail: amghouz.uo@uniovi.es [Servicios Científico Técnicos, Universidad de Oviedo, 33006 Oviedo (Spain); Khainakov, Sergei A. [Servicios Científico Técnicos, Universidad de Oviedo, 33006 Oviedo (Spain); Alfonso, Belén F.; Blanco, Jesús A. [Departamento de Física, Universidad de Oviedo, 33007 Oviedo (Spain); García, José R.; García-Granda, Santiago [Departamentos de Química Física y Analítica y Química Orgánica e Inorgánica, Universidad de Oviedo-CINN, 33006 Oviedo (Spain)

    2015-05-15

    A two-dimensional piperazinium cobalt–zinc phosphate, formulated as (C{sub 4}N{sub 2}H{sub 12}){sub 1.5}(Co{sub 0.6}Zn{sub 0.4}){sub 2}(HPO{sub 4}){sub 2}(PO{sub 4})·H{sub 2}O (2D), was synthesized under hydrothermal conditions. The crystal structure was determined using single-crystal X-ray diffraction data (monoclinic P2{sub 1}/c, a=8.1165(3) Å, b=26.2301(10) Å, c=8.3595(4) Å, and β=110.930(5)°) and the hydrogen atom positions were optimized by DFT calculations. A single-crystal corresponding to one-dimensional metastable phase, (C{sub 4}N{sub 2}H{sub 12})Co{sub 0.3}Zn{sub 0.7}(HPO{sub 4}){sub 2}·H{sub 2}O (1D), was also isolated and the crystal structure was determined (monoclinic P2{sub 1}/c, a=8.9120(6) Å, b=14.0290(1) Å, c=12.2494(5) Å, and β=130.884(6)°). The bulk was characterized by chemical (C–H–N) analysis, powder X-ray diffraction (PXRD), powder X-ray thermodiffractometry (HT-XRD), transmission electron microscopy (STEM(DF)-EDX and EFTEM), and thermal analysis (TG/SDTA-MS), including activation energy data of its thermal decomposition. The magnetic susceptibility and magnetization measurements show no magnetic ordering down to 4 K. - Graphical abstract: Hydrothermal synthesis and structural characterization of a two-dimensional piperazinium cobalt–zinc phosphate, (C{sub 4}N{sub 2}H{sub 12}){sub 1.5}(Co{sub 0.6}Zn{sub 0.4}){sub 2}(HPO{sub 4}){sub 2}(PO{sub 4})·H{sub 2}O (2D), have been reported. The crystal structure of a one-dimensional piperazinium cobalt–zinc phosphate, (C{sub 4}N{sub 2}H{sub 12})Co{sub 0.3}Zn{sub 0.7}(HPO{sub 4}){sub 2}·H{sub 2}O (1D) a metastable phase during the hydrothermal synthesis, was also determined. The thermal behavior of 2D compound is strongly dependent on the selected heating rate and the magnetic susceptibility and magnetization measurements show no magnetic ordering down to 4 K. - Highlights: • A 2D piperazinium cobalt–zinc phosphate has been synthesized and characterized. • Crystal

  9. Synthesis, characterization and comparison of polythiophene ...

    Indian Academy of Sciences (India)

    38

    Synthesis, characterization and comparison of polythiophene-carbon ... b Nanotechnology Research Institute, School of Chemical Engineering, Babol University of Technology, Babol, ..... The scan range was from −0.24 to 1.2 V in reference to.

  10. Numerical characterization of nanopillar photonic crystal waveguides and directional couplers

    DEFF Research Database (Denmark)

    Chigrin, Dmitry N.; Lavrinenko, Andrei; Sotomayor Torres, Clivia M.

    2005-01-01

    We numerically characterize a novel type of a photonic crystal waveguide, which consists of several rows of periodically arranged dielectric cylinders. In such a nanopillar photonic crystal waveguide, light confinement is due to the total internal reflection. A nanopillar waveguide is a multimode...

  11. Synthesis, Characterization, and Computational Modeling of N-(1-Ethoxyvinylpyridinium Triflates, an Unusual Class of Pyridinium Salts

    Directory of Open Access Journals (Sweden)

    Jonathan D. Shapiro

    2018-02-01

    Full Text Available N-Substituted pyridinium salts constitute one of the most valuable reagent classes in organic synthesis, due to their versatility and ease of use. Herein we report a preliminary synthesis and detailed structural analysis of several N-(1-ethoxyvinylpyridinium triflates, an unusual class of pyridinium salts with potentially broad use as a reagent in organic synthesis. Treatment of pyridines with trifluoromethane sulfonic acid and ethoxyacetylene generates stable, isolable adducts which have been extensively characterized, due to their novelty. Three-dimensional structural stability is perpetuated by an array of C–H•••O hydrogen bonds involving oxygen atoms from the –SO3 groups of the triflate anion, and hydrogen atoms from the aromatic ring and vinyl group of the pyridinium cation. Predictions from density functional theory calculations of the energy landscape for rotation about the exocyclic C–N bond of 2-chloro-1-(1-ethoxyvinylpyridine-1-ium trifluoromethanesulfonate (7 and 1-(1-ethoxyvinylpyridine-1-ium trifluoromethanesulfonate (16 are also reported. Notably, the predicted global energy minimum of 7 was nearly identical to that found within the crystal structure.

  12. Synthesis and crystal structures of three new benzotriazolylpropanamides

    Directory of Open Access Journals (Sweden)

    Donna S. Amenta

    2017-06-01

    Full Text Available The base-catalyzed Michael addition of 2-methylacrylamide to benzotriazole afforded 3-(1H-benzotriazol-1-yl-2-methylpropanamide, C10H12N4O (1, in 32% yield in addition to small amounts of isomeric 3-(2H-benzotriazol-2-yl-2-methylpropanamide, C10H12N4O (2. In a similar manner, 3-(1H-benzotriazol-1-yl-N,N-dimethylpropanamide, C11H14N4O (3, was prepared from benzotriazole and N,N-dimethylacrylamide. All three products have been structurally characterized by single-crystal X-ray diffraction. The crystal structures of 1 and 2 comprise infinite arrays formed by N—H...O and N—H...N bridges, as well as π–π interactions, while the molecules of 3 are aggregated to simple π-dimers in the crystal.

  13. Synthesis and characterization of nano silicon and titanium nitride ...

    Indian Academy of Sciences (India)

    The characterization techniques indicated ... Scalable synthesis; microwave plasma; chemical synthesis; nanoparticles. 1. Introduction ... used but very few methods are available to produce silicon and titanium ... current (A). (m3/h). 1. Si. 2.1.

  14. Synthesis, characterization, crystal structure and theoretical study of a compound with benzodiazole ring: antimicrobial activity and DNA binding.

    Science.gov (United States)

    Latha, P; Kodisundaram, P; Sundararajan, M L; Jeyakumar, T

    2014-08-14

    2-(Thiophen-2-yl)-1-((thiophen-2-yl)methyl)-1H-1,3-benzodiazole (HL) is synthesized and characterized by elemental analysis, UV-Vis, FT-IR, (1)H, (13)C NMR, mass spectra, scanning electron microscope (SEM) and single crystal X-ray diffraction. The crystal structure is stabilized by intermolecular CH⋯N and CH⋯π interactions. The molecular structure is also optimized at the B3LYP/6-31G level using density functional theory (DFT). The structural parameters from the theory are nearer to those of crystal, the calculated total energy of coordination is -1522.814a.u. The energy of HOMO-LUMO and the energy gap are -0.20718, -0.04314, 0.16404a.u, respectively. All data obtained from the spectral studies support the structural properties of the compound HL. The benzimidazole ring is essentially planar. The in vitro biological screening effects of the synthesized compound is tested against four bacterial and four fungal strains by well diffusion method. Antioxidant property and DNA binding behaviour of the compound has been investigated using spectrophotometric method. Copyright © 2014 Elsevier B.V. All rights reserved.

  15. Synthesis, Crystal Structure, and Topology-Symmetry Analysis of a New Modification of NaIn[IO3]4

    Science.gov (United States)

    Belokoneva, E. L.; Karamysheva, A. S.; Dimitrova, O. V.; Volkov, A. S.

    2018-01-01

    Crystals of new iodate NaIn[IO3]4 were prepared by the hydrothermal synthesis. The unit cell parameters are a = 7.2672(2) Å, b = 15.2572(6) Å, c = 15.0208(6) Å, β = 101.517(3)°, sp. gr. P21/ c. The formula was determined during the structure determination and refinement of a twinned crystal based on a set of reflections from the atomic planes of the major individual. The refinement with anisotropic displacement parameters was performed for both twin components to the final R factor of 0.050. The In and Na atoms are in octahedral coordination formed by oxygen atoms. The oxygen octahedra are arranged into columns by sharing edges, and the columns are connected by isolated umbrella-like [IO3]- groups to form layers. The new structure is most similar to the isoformular iodate NaIn[IO3]4, which crystallizes in the same sp. gr. P21/ c and is structurally similar, but has a twice smaller unit cell and is characterized by another direction of the monoclinic axis. The structural similarity and difference between the two phases were studied by topologysymmetry analysis. The formation of these phases is related to different combinations of identical one-dimensional infinite chains of octahedra.

  16. Studies of the kinetics and mechanisms of ammonia synthesis and hydrodesulfurization on metal single-crystal surfaces

    International Nuclear Information System (INIS)

    Gellman, A.J.; Asscher, M.; Somorjai, G.A.

    1985-01-01

    The authors studied the ammonia synthesis reaction over Fe and Re single crystal surfaces and the hydrodesulfurization of thiophene over the Mo(100) single crystal surface. The studies have been performed using UHV surface science tools with the capability of exposing the surfaces to high pressure, high temperature reaction conditions. The ammonia synthesis reaction was shown to be extremely sensitive to surface structure on both Fe and Re, favoring surfaces with a rough or open topography. The HDS reaction on the Mo(100) surface has been shown to be similar to that on MoS/sub 2/ and appears to proceed via a reaction path that does not produce a strong Mo-S bond as an intermediate species

  17. Synthesis, characterization, antimicrobial activity and molecular ...

    African Journals Online (AJOL)

    Synthesis, characterization, antimicrobial activity and molecular docking studies of combined pyrazol-barbituric acid pharmacophores. Assem Barakat, Bandar M. Al-Qahtani, Abdullah M. Al-Majid, M. Ali Mohammed Rafi Shaik, Mohamed H.M. Al-Agamy, Abdul Wadood ...

  18. synthesis and optical characterization of acid-doped polyaniline thin

    African Journals Online (AJOL)

    HOD

    SYNTHESIS AND OPTICAL CHARACTERIZATION OF ACID-DOPED. POLYANILINE THIN .... MATERIALS AND METHODS .... Characterization of Se Doped Polyaniline”,Current. Applied ... with Silver Nanoparticles”, Advances in Materials.

  19. Low temperature synthesis and characterization of Na–M–(O)–F phases with M=Ti, V

    Energy Technology Data Exchange (ETDEWEB)

    Nava-Avendaño, Jessica [Institut de Ciència de Materials de Barcelona (ICMAB-CSIC), Campus UAB, E-08193 Bellaterra, Catalonia (Spain); Ayllón, José A. [Departament de Química, Universitat Autònoma de Barcelona, Campus UAB, E-08193 Bellaterra, Catalonia (Spain); Frontera, Carlos; Oró-Solé, Judith [Institut de Ciència de Materials de Barcelona (ICMAB-CSIC), Campus UAB, E-08193 Bellaterra, Catalonia (Spain); Estruga, Marc [Departament de Química, Universitat Autònoma de Barcelona, Campus UAB, E-08193 Bellaterra, Catalonia (Spain); Molins, Elies [Institut de Ciència de Materials de Barcelona (ICMAB-CSIC), Campus UAB, E-08193 Bellaterra, Catalonia (Spain); Palacín, M. Rosa, E-mail: rosa.palacin@icmab.es [Institut de Ciència de Materials de Barcelona (ICMAB-CSIC), Campus UAB, E-08193 Bellaterra, Catalonia (Spain)

    2015-03-15

    Na{sub 5}Ti{sub 3}O{sub 3}F{sub 11} was prepared by the microwave assisted method, and presents a chiolite related structure with cell parameters a=10.5016(5), b=10.4025(5), and c=10.2911(5) Å and Cmca (no. 64) space group. From solvothermal synthesis at 100 °C the cryolite Na{sub 3−δ}VO{sub 1−δ}F{sub 5+δ} was prepared, which crystallizes in the monoclinic system with a=5.5403(2), b=5.6804(2), c=7.9523(2) Å, β=90.032(7)° cell parameters and P2{sub 1}/n (no. 14) space group. Under similar synthesis conditions but with higher HF concentration the chiolite-type phase Na{sub 5−δ}V{sub 3}F{sub 14} was achieved, which exhibits a=10.5482(2), b=10.4887(1) and c=10.3243(1) Å cell parameters and Cmc2{sub 1} (no. 36) space group. A single crystal also having the chiolite structure was synthesized at 200 °C which exhibits tetragonal symmetry (a=7.380(3) and c=10.381(11) Å and space group P4{sub 2}2{sub 1}2 (no. 94)). Bond valence sum indicates that it contains V{sup 4+} and therefore can be formulated as Na{sub 5}V{sub 3}O{sub 3}F{sub 11}. - Graphical abstract: Na{sub 5}M{sub 3}(O,F){sub 14} with M=Ti and V having chiolite structure and Na{sub 3−δ}VO{sub 1−δ}F{sub 5+δ} cryolite were prepared by means of microwave-assisted and solvothermal synthesis. - Highlights: • Na{sub 5}Ti{sub 3}O{sub 3}F{sub 11} chiolite was prepared by a microwave assisted method and characterized. • Na{sub 3−δ}VO{sub 1−δ}F{sub 5+δ} and Na{sub 5−δ}V{sub 3}F{sub 14} were prepared by solvothermal synthesis. • The compounds were structurally characterized by diffraction techniques. • O/F distribution was estimated by applying Pauling’s second rule.

  20. Synthesis, Characterization, Antimicrobial Activity and Antioxidant ...

    African Journals Online (AJOL)

    MBI

    2015-12-08

    Dec 8, 2015 ... Synthesis, Characterization, Antimicrobial Activity and Antioxidant. Studies of ... Transition metal complexes of Co(II) and Ni(II) with Schiff base ligand (HL) derived from condensation of 2- ..... 2-((5mercapto-1,3,4-thiadiazol-2-.

  1. Characterization of pure and copper-doped iron tartrate crystals

    Indian Academy of Sciences (India)

    Single crystal growth of pure and copper-doped iron tartrate crystals bearing composition Cu Fe(1−) C4H4O6 · H2O, where = 0, 0.07, 0.06, 0.05, 0.04, 0.03, is achieved using gel technique. The elemental analysis has been done using energy-dispersive X-ray analysis (EDAX) spectrum. The characterization studies ...

  2. Studies on synthesis of diamond at high pressure and temperature

    Science.gov (United States)

    Kailath, Ansu J.

    chapter is a general introduction incorporating the information regarding diamond together with a brief history of diamond synthesis. It also includes the details of the high pressure synthesis of diamond, the uses of diamond grits, the advantages of the synthetic diamond grit over natural grit and an outline to elucidate the reasons which prompted to undertake the present work. The details of the technique used in the present studies for synthesis of diamond grits by high-pressure high-temperature process are included in chapter II. The hydraulic press used for synthesis, the details of the reactant materials, stacking of the high pressure cell and the details of synthesis run have been described together with the separation procedure to isolate diamond grits from the frozen slug. Different analytical and characterization techniques used in the present studies for the analysis and characterization of the reactant materials, synthesized diamonds and the crystallization medium have been illustrated in chapter III. The effect of different synthesizing parameters on synthesized diamond crystals were studied. This study includes: (a) dependence of yield of diamond on temperature and pressure, (b) dependence of crystal size on cook length, (c) effect of variation of the relative amounts of carbonaceous material and catalyst on synthesis, (d) morphological variation and (e) effect of pressure pulse on synthesized crystals. Various observations made during this study and the results obtained have been compiled in chapter IV. The synthesized diamond crystals were characterized by X-ray Powder Diffraction (XRD), Raman Spectroscopy, Scanning Electron Microscopy (SEM) and Optical Microscopy. The results obtained have been compiled in chapter V. In addition to these, the results obtained from the Infrared Spectra and the Electron Paramagnetic Spectra have also been included. Studies of crystallization medium and inclusions in the synthesized diamonds were carried out. This include

  3. Synthesis and crystal structure of the first Sc-Nb-O-N phases

    Energy Technology Data Exchange (ETDEWEB)

    Orthmann, Steven; Lerch, Martin [Institut fuer Chemie, Technische Universitaet Berlin (Germany)

    2017-11-17

    Synthesis of phase-pure materials in the system Sc-Nb-O-N is challenging. In this contribution we report on the preparation of the first scandium niobium oxide nitrides via reaction of water-saturated gaseous ammonia or an ammonia-oxygen mixture with amorphous scandium niobium oxides. Two new phases were obtained: rutile-type ScNb{sub 4}O{sub 7}N{sub 3}, which crystallizes in space group P4{sub 2}/mnm, and an anion-deficient fluorite-type Sc{sub 2}Nb(O,N,⬜){sub 6} phase crystallizing in space group Fm anti 3m. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  4. Ligand mediated synthesis of AgInSe2 nanoparticles with tetragonal/orthorhombic crystal phases

    International Nuclear Information System (INIS)

    Abazović, Nadica D.; Čomor, Mirjana I.; Mitrić, Miodrag N.; Piscopiello, Emanuela; Radetić, Tamara; Janković, Ivana A.; Nedeljković, Jovan M.

    2012-01-01

    Nanosized AgInSe 2 particles (d ∼ 7–25 nm) were synthesized using colloidal chemistry method at 270 °C. As solvents/surface ligands 1-octadecene, trioctylphosphine, and oleylamine were used. It was shown that choice of ligand has crucial impact not only on final crystal phase of nanoparticles, but also at mechanism of crystal growth. X-ray diffraction and TEM/HRTEM techniques were used to identify obtained crystal phases and to measure average size and shape of nanoparticles. UV/Vis data were used to estimate band-gap energies of obtained samples. It was shown that presented routes can provide synthesis of nanoparticles with desired crystal phase (tetragonal and/or orthorhombic), with band-gap energies in the range from 1.25 to 1.53 eV.

  5. Mechanosynthesis, crystal structure and magnetic characterization of neodymium orthoferrite

    Energy Technology Data Exchange (ETDEWEB)

    Serna, Pedro Vera; Campos, Cecilio Garcia [Division de Ingenierias, Universidad Politecnica de Tecamac (UPTECAMAC), Tecamac de Felipe Villanueva, Estado de Mexico (Mexico); De Jesus, Felix Sanchez; Miro, Ana Maria Bolarin [Area Academica de Ciencias de la Tierra y Materiales, Universidad Autonoma del Estado de Hidalgo (UAEH), Mineral de la Reforma, Hidalgo (Mexico); Loran, Jose Antonio Juanico [Division de Ingenieria Industrial Nanotecnologia, Universidad Politecnica del Valle de Mexico (UPVM), Tultitlan, Estado de Mexico (Mexico); Longwell, Jeffrey, E-mail: pedrovera.upt@gmail.com [Department of Languages and Linguistics, New Mexico State University (NMSU), Las Cruces, NM (United States)

    2016-03-15

    Neodymium orthoferrite NdFeO{sub 3} was obtained at room temperature by mechanosynthesis with a stoichiometric ratio of Nd2O{sub 3} and Fe{sub 2}O{sub 3} powders, whereas the traditional synthesis requires a temperature of approximately 1000 °C. The crystal structure was analyzed by X-ray diffraction analysis using Cu radiation and a LynxEye XE detector, whose strong fluorescence filtering enabled a high signal intensity. The analysis indicated that the obtained crystallites were nano-sized. The particle morphology was observed by scanning electron microscopy, and the magnetic saturation was tested by vibrating sample magnetometry. The synthesis of NdFeO{sub 3} was detected after a few hours of milling, indicating that the milling imparted mechanical energy to the system. (author)

  6. Synthesis and characterization of tricalcium phosphate ceramics doped with zinc

    International Nuclear Information System (INIS)

    Kai, K.C.; Marchi, J.; Ussui, V.; Bressiani, A.H.A.

    2011-01-01

    Due to its biocompatibility, the tricalcium phosphate (TCP) is used as a biomaterial for bone replacement and reconstruction. Zinc (Zn) can replace calcium in the crystal structure of TCP to be added in small quantities, can result in stimulatory effects on bone formation in vitro and in vivo. In this work, pure TCP and Zn-TCP, with general formula (Ca_1_-_xZn_x)_3 (PO_4)_2 and 0 ≤ x ≤ 0.0225, were prepared by wet synthesis, from precursors Ca(OH)_2, H_3PO_4 and ZnO, after calcinated at 800 deg C and characterized by X-ray diffraction, specific surface area, agglomerate size distribution, differential thermal analysis and scanning electron microscopy. The results showed that the addition of small amounts of Zn resulted in TCP with suitable densification and higher specific surface area, may be promising as biomaterial due to the stimulatory effects of zinc associated with suitable mechanical properties of the final material. (author)

  7. short communication synthesis and crystal structure of a polymeric

    African Journals Online (AJOL)

    Preferred Customer

    A new polymeric zinc(II) complex, [ZnL2(PDA)]n, has been prepared by the reaction of zinc sulfate ... complex has been characterized by single-crystal X-ray diffraction. .... Molecular structure of the complex at 30% probability displacement.

  8. Facile synthesis and structure characterization of hexagonal tungsten bronzes crystals

    Science.gov (United States)

    Lee, Jiann-Shing; Liu, Hao-Chuan; Peng, Gao-De; Tseng, Yawteng

    2017-05-01

    A facile molten-salt route was used to synthesize hexagonal Cs0.33WO3, Rb0.33WO3 and K0.30WO3 crystals. The three isostructural compounds were successfully prepared from the reaction of MxWO3 powders (M = Cs, Rb, K) in the CsCl/NaCl, RbCl/NaCl and KCl/NaCl fluxes, respectively. The structure determination and refinement, based on single-crystal X-ray diffraction data, are in agreement with previous works, possessing space group P63/mcm. The a and c parameters vary non-linearly with increasing radii of the M+ cations (rM) that is coordinated to twelve oxygen atoms. Both the volumes of unit-cell and WO6 octahedra vary linearly with rM, which become smaller from Cs0.33WO3 to K0.30WO3. The distortion of WO6 octahedra as well as isotropic displacement parameters increases from Cs0.33WO3 to K0.30WO3. The geometry of the WO6 octahedron becomes more regular with increasing rM. These structural trends arise from the effective size of the M+ cation.

  9. Synthesis and characterization of metal soaps of lanthanides (III)

    International Nuclear Information System (INIS)

    Payolla, Filipe Boccato; Ribeiro, Sidney Jose Lima; Massbni, Antonio Carlos

    2015-01-01

    The present study describes synthesis and partial characterization of Eu"3"+, Nd"3"+, Dy"3"+, Tb"3"+ and Yb"3"+ behenate complexes. The compounds were analyzed using IR-Spectroscopy, TG-DTG, DSC, elemental analysis, XRD, luminescence and SEM. The results show the purity of the compounds. The XRD analysis and the SEM images show the high crystallinity of the complexes. TG-DTG and DSC analyses do not show a liquid crystal behavior, as occurs with other lanthanide metallic soaps. The mass loses until 1000° C show that the compounds lose ligand fragments at specific temperatures. XRD of the residues are compatible with the respective lanthanide oxides. The luminescence analysis shows that the Eu"3"+, Nd"3"+ and Tb"3"+ complexes presents appreciable emission. The Judd-Ofelt parameters obtained are compatible with the values found in the literature. It was not possible to obtain the complexes in a glass-form because it is difficult to prevent the crystallization of the complexes even using liquid nitrogen. The XDR data indicate that one of the complexes axis has 52 Å of length, agreeing with a structure containing behenate-lanthanide ion-behenate. The structures of the complexes were not fully elucidated and more analyses are necessary. The complexes presented a molar ratio of 3:1 (L:M) and were formulated as Bh_3Eu, Bh_3Nd, Bh_3Dy, Bh_3Tb e Bh_3Yb (Bh = behenate anion). (author)

  10. Soft chemistry routes to transparent metal oxide thin films. The case of sol–gel synthesis and structural characterization of Ta2O5 thin films from tantalum chloromethoxide

    International Nuclear Information System (INIS)

    Epifani, Mauro; Zamani, Reza; Arbiol, Jordi; Fabrega, Cristian; Andreu, Teresa; Pace, Giovanni Battista; Siciliano, Pietro; Morante, Joan R.

    2014-01-01

    Ta 2 O 5 thin films were prepared by spin-coating methanol solutions of Ta chloromethoxide. It was prepared by reacting TaCl 5 with methanol, followed by water addition (H 2 O: Ta molar ratio was 16). Thin films were deposited by spin-coating onto SiO 2 /Si substrates, followed by drying at 90 °C and heat-treatment up to 700 °C. The films were characterized by X-ray diffraction, transmission electron microscopy and field emission scanning electron microscopy. Crystallization was obtained only after heating at 700 °C, in the Ta 2 O 5 orthorhombic phase. The resulting films had a thickness of 100 nm. Their structure was constituted by porous crystals with size up to 50 nm, while the pores had a size of about 10 nm. The results demonstrated that TaCl 5 is very convenient precursor for the wet chemical synthesis of Ta 2 O 5 thin films. - Highlights: • Development of convenient solution synthesis of Ta 2 O 5 thin films; • The precursor chemistry was established and related to the synthesis process; • Uniform films crystallized in the most stable orthorombic Ta 2 O 5 phase;

  11. Preparation and characterization of superfine ammonium perchlorate (AP) crystals through ceramic membrane anti-solvent crystallization

    Science.gov (United States)

    Ma, Zhenye; Li, Cheng; Wu, Rujun; Chen, Rizhi; Gu, Zhenggui

    2009-10-01

    In this paper, a novel ceramic membrane anti-solvent crystallization (CMASC) method was proposed for the safe and rapid preparation ammonium perchlorate (AP) crystals, in which the acetone and ethyl acetate were chosen as solvent and anti-solvent, respectively. Comparing with the conventional liquid anti-solvent crystallization (LASC), CMASC which successfully introduces ceramic membrane with regular pore structure to the LASC as feeding medium, is favorable to control the rate of feeding rate and, therefore, to obtain size and morphology controllable AP. Several kinds of micro-sized AP particles with different morphology were obtained including polyhedral-like, quadrate-like to rod-like. The effect of processing parameters on the crystal size and shape of AP crystals such as volume ratio of anti-solvent to solvent, feeding pressure and crystallization temperature were investigated. It is found that higher volume ratio of anti-solvent to solvent, higher feeding pressure and higher temperature result in smaller particle size. Scaning electron microscopy (SEM) and X-ray diffraction (XRD) were used to characterize the resulting AP crystals. The nucleation and growth kinetic of the resulting AP crystals were also discussed.

  12. Synthesis and characterization of nanosized ceria powders by microwave-hydrothermal method

    International Nuclear Information System (INIS)

    Bonamartini Corradi, A.; Bondioli, F.; Ferrari, A.M.; Manfredini, T.

    2006-01-01

    Nanocrystalline ceria powders (CeO 2 ) have been prepared by adding NaOH to a cerium ammonium nitrate aqueous solution under microwave-hydrothermal conditions. In particular the effect of the synthesis conditions (time, pressure and concentration of both the precursor and the precipitant agent solutions) on the physical properties of the crystals have been evaluated. Microwave-hydrothermal treatment of 5 min at 13.4 atm allows to obtain almost crystallized powders (amorphous phase 4%) as underlined by Rietveld-reference intensity ratio (RIR) results

  13. Synthesis, characterization and physiological activity of some novel isoxazoles.

    Directory of Open Access Journals (Sweden)

    NITIN G. GHODILE

    2012-07-01

    Full Text Available Hushare VJ, Rajput PR, Malpani MO, Ghodile NG. 2012. Synthesis, characterization and physiological activity of some novel isoxazoles. Nusantara Bioscience 4: 81-85. A series of chlorosubstituted 4-aroylisoxazoles have been synthesized by refluxing chlorosubstituted-3-aroylflavones and 3-alkoylchromone with hydroxylamine hydrochloride in dioxane medium containing 0.5 mL piperidine. Chlorosubstituted-3-aroylflavones and chlorosubstituted-3-alkoylchromone were prepared by refluxing them separately with iodine crystal in ethanol. Initially chlorosubstituted-3-aroylflavanones and 3-alkoylchromanone were prepared by the interaction of different aromatic and aliphatic aldehydes with 1-(2’-hydroxy-3’,5’-dichlorophenyl-3-phenyl-1,3-propanedione. Constitutions of synthesized compounds were confirmed on the basis of elemental analysis, molecular weight determination, UV-Visible, I.R. and 1H-NMR spectral data. The titled compounds were evaluated for their growth promoting activity on some flowering plants viz. Papaver rhoeas, Calendula officinalise, Gladiola tristis, Gaillardia aristata, Dianthus chinensis, and Iberis sp. (candytuft. The results indicate that applicated plants had higher shoots and more number of leaves.

  14. Characterization of Crystal Chirality in Amino Acids Using Low-Frequency Raman Spectroscopy.

    Science.gov (United States)

    Aviv, Hagit; Nemtsov, Irena; Mastai, Yitzhak; Tischler, Yaakov R

    2017-10-19

    We present a new method for differentiating racemic crystals from enantiopure crystals. Recently, developments in optical filters have enabled the facile use of Raman spectroscopy to detect low-frequency vibrational (LFV) modes. Here, for the first time, we use Raman spectroscopy to characterize the LFV modes for crystalline organic materials composed of chiral molecules. The LF-Raman spectra of racemic and enantiopure crystals exhibit a significant variation, which we attribute to different hydrogen-bond networks in the chiral crystal structures. Across a representative set of amino acids, we observed that when comparing racemic versus enantiopure crystals, the available LFV modes and their relative scattering intensity are strong functions of side chain polarity. Thus, LF-Raman can be used as a method that is complementary to the currently used methods for characterizing crystal chirality due to simpler, faster, and more sensitive measurements, along with the small sample size required, which is limited by the laser-beam diameter in the focus.

  15. Synthesis, characterization and single crystal x-ray analysis of a complex of iron(II) bis(2,4-dimethylphenyl)dithiophosphate with 4-ethylpyridine

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Sandeep; Andotra, Savit; Kaur, Mandeep [University of Jammu, Department of Chemistry (India); Gupta, Vivek K.; Kant, Rajni [Department of Physics and Electronics, University of Jammu, X-ray Crystallographic Laboratory (India); Pandey, Sushil K., E-mail: kpsushil@rediffmail.com [University of Jammu, Department of Chemistry (India)

    2016-09-15

    Complex of iron(II) bis(2,4-dimethylphenyl)dithiophosphate with 4-ethylpyridine [((2,4- (CH{sub 3}){sub 2}C{sub 6}H{sub 3}O)2PS2)2Fe(NC{sub 5}H{sub 4}(C{sub 2}H{sub 5})-4){sub 2}] is synthesized and characterized by elemental analysis, magnetic moment, IR spectroscopy and single crystal X-ray analysis. Complex crystallizes in the monoclinic sp. gr. P2{sub 1}/n, Z = 2. Crystal structure consists of mononuclear units with Fe(II) ion chelated by four S atoms of the two diphenyldithiophosphate ligands in bidentate manner. N atoms from two 4-ethylpyridine ligands are axially coordinated to the Fe(II) atom leading to an octahedral geometry.

  16. A HPMT based set-up to characterize scintillating crystals

    International Nuclear Information System (INIS)

    D'Ambrosio, C.; Ercoli, C.; Jaaskelainen, S.; Lecoeur, G.; Leutz, H.; Loos, R.; Piedigrossi, D.; Puertolas, D.; Rosso, E.; Schomaker, R.

    1999-01-01

    We have developed a fully automatic measurement set-up, capable of measuring light yields arising from scintillating crystals in a linear range of about four orders of magnitude. The photodetector is a hybrid photomultiplier tube specially developed to optimize linear range and photon detection. Crystal and photodetector are temperature controlled by a closed water circuit, as this is essential when measuring low light yield scintillating crystals with a marked temperature dependence of their light yield. Gamma sources can be placed either on top or on the side of the crystal. In this latter case, the source can be automatically moved by a computer-controlled step motor to provide a uniformity profile of the light yield along the crystal. Tagged and not-tagged operation modes are possible. The whole set-up is computer-controlled in an effort to provide fast and reliable measurements, to characterize many crystals per day. This is important for the quality control of the lead tungstate crystals that will be applied in the electromagnetic calorimeter of the CMS-detector at the LHC at CERN. (author)

  17. A HPMT based set-up to characterize scintillating crystals

    Energy Technology Data Exchange (ETDEWEB)

    D' Ambrosio, C.; Ercoli, C.; Jaaskelainen, S.; Lecoeur, G.; Leutz, H.; Loos, R.; Piedigrossi, D.; Puertolas, D.; Rosso, E.; Schomaker, R

    1999-09-21

    We have developed a fully automatic measurement set-up, capable of measuring light yields arising from scintillating crystals in a linear range of about four orders of magnitude. The photodetector is a hybrid photomultiplier tube specially developed to optimize linear range and photon detection. Crystal and photodetector are temperature controlled by a closed water circuit, as this is essential when measuring low light yield scintillating crystals with a marked temperature dependence of their light yield. Gamma sources can be placed either on top or on the side of the crystal. In this latter case, the source can be automatically moved by a computer-controlled step motor to provide a uniformity profile of the light yield along the crystal. Tagged and not-tagged operation modes are possible. The whole set-up is computer-controlled in an effort to provide fast and reliable measurements, to characterize many crystals per day. This is important for the quality control of the lead tungstate crystals that will be applied in the electromagnetic calorimeter of the CMS-detector at the LHC at CERN. (author)

  18. Photocatalytic semiconductors synthesis, characterization, and environmental applications

    CERN Document Server

    Hernández-Ramírez, Aracely

    2014-01-01

    This critical volume examines the different methods used for the synthesis of a great number of photocatalysts, including TiO2, ZnO and other modified semiconductors, as well as characterization techniques used for determining the optical, structural and morphological properties of the semiconducting materials. Additionally, the authors discuss photoelectrochemical methods for determining the light activity of the photocatalytic semiconductors by means of measurement of properties such as band gap energy, flat band potential and kinetics of hole and electron transfer. Photocatalytic Semiconductors: Synthesis, Characterization and Environmental Applications provide an overview of the semiconductor materials from first- to third-generation photocatalysts and their applications in wastewater treatment and water disinfection. The book further presents economic and toxicological aspects in the production and application of photocatalytic materials.

  19. Fully automatic characterization and data collection from crystals of biological macromolecules

    International Nuclear Information System (INIS)

    Svensson, Olof; Malbet-Monaco, Stéphanie; Popov, Alexander; Nurizzo, Didier; Bowler, Matthew W.

    2015-01-01

    A fully automatic system has been developed that performs X-ray centring and characterization of, and data collection from, large numbers of cryocooled crystals without human intervention. Considerable effort is dedicated to evaluating macromolecular crystals at synchrotron sources, even for well established and robust systems. Much of this work is repetitive, and the time spent could be better invested in the interpretation of the results. In order to decrease the need for manual intervention in the most repetitive steps of structural biology projects, initial screening and data collection, a fully automatic system has been developed to mount, locate, centre to the optimal diffraction volume, characterize and, if possible, collect data from multiple cryocooled crystals. Using the capabilities of pixel-array detectors, the system is as fast as a human operator, taking an average of 6 min per sample depending on the sample size and the level of characterization required. Using a fast X-ray-based routine, samples are located and centred systematically at the position of highest diffraction signal and important parameters for sample characterization, such as flux, beam size and crystal volume, are automatically taken into account, ensuring the calculation of optimal data-collection strategies. The system is now in operation at the new ESRF beamline MASSIF-1 and has been used by both industrial and academic users for many different sample types, including crystals of less than 20 µm in the smallest dimension. To date, over 8000 samples have been evaluated on MASSIF-1 without any human intervention

  20. Fully automatic characterization and data collection from crystals of biological macromolecules

    Energy Technology Data Exchange (ETDEWEB)

    Svensson, Olof; Malbet-Monaco, Stéphanie; Popov, Alexander; Nurizzo, Didier, E-mail: nurizzo@esrf.fr [European Synchrotron Radiation Facility, 71 Avenue des Martyrs, CS 40220, 38043 Grenoble (France); Bowler, Matthew W., E-mail: nurizzo@esrf.fr [European Molecular Biology Laboratory, Grenoble Outstation, 71 Avenue des Martyrs, CS 90181, 38042 Grenoble (France); Université Grenoble Alpes–EMBL–CNRS, Grenoble Outstation, 71 Avenue des Martyrs, CS 90181, 38042 Grenoble (France); European Synchrotron Radiation Facility, 71 Avenue des Martyrs, CS 40220, 38043 Grenoble (France)

    2015-07-31

    A fully automatic system has been developed that performs X-ray centring and characterization of, and data collection from, large numbers of cryocooled crystals without human intervention. Considerable effort is dedicated to evaluating macromolecular crystals at synchrotron sources, even for well established and robust systems. Much of this work is repetitive, and the time spent could be better invested in the interpretation of the results. In order to decrease the need for manual intervention in the most repetitive steps of structural biology projects, initial screening and data collection, a fully automatic system has been developed to mount, locate, centre to the optimal diffraction volume, characterize and, if possible, collect data from multiple cryocooled crystals. Using the capabilities of pixel-array detectors, the system is as fast as a human operator, taking an average of 6 min per sample depending on the sample size and the level of characterization required. Using a fast X-ray-based routine, samples are located and centred systematically at the position of highest diffraction signal and important parameters for sample characterization, such as flux, beam size and crystal volume, are automatically taken into account, ensuring the calculation of optimal data-collection strategies. The system is now in operation at the new ESRF beamline MASSIF-1 and has been used by both industrial and academic users for many different sample types, including crystals of less than 20 µm in the smallest dimension. To date, over 8000 samples have been evaluated on MASSIF-1 without any human intervention.

  1. Synthesis and crystal chemistry of transuranium element chalcogenides. Contribution to the study of the 5f electron localization

    International Nuclear Information System (INIS)

    Damien, Daniel.

    1976-09-01

    The synthesis and crystal chemistry of Np, Pu, Am and Cm transuranium element chalcogenides are described. From plutonium, transuranium element chalcogenides exhibit the same crystal structure as their rare-earth homologues. The variations of the lattice constants of these compounds in terms of the atomic number are characterized by the lack of the 5f contraction and are interpreted by a localization of the 5f electrons depending upon the considered transuranium element, the nature of the ligand and the crystal structure. To compare the degree of magnitude of the 5f electron delocalization in various compounds, a delocalization scale is proposed based on a comparison between the molar volumes of actinide and isostructural lanthanide compounds. This scale provides a delocalization coefficient for each compound under study. Examination of these coefficients shows that the 5f electrons, in series of actinide compounds, become localized when going from neptunium to curium and that the delocalization process does not only depend upon overlaps between 5f-6d orbitals of neighbouring actinide atoms; the delocalization coefficients show the existence of a secondary delocalization effect due to overlaps between the p anion and f actinide orbitals which are more important for the Vb anion group (N, P, As, Sb) than for the Vib one (S,Se,Te) [fr

  2. Synthesis and characterization of bulk Cu2ZnSnX4 (X: S, Se) via thermodynamically supported mechano-chemical process

    International Nuclear Information System (INIS)

    Pareek, Devendra; Balasubramaniam, K.R.; Sharma, Pratibha

    2015-01-01

    Materials with the general formula, Cu 2 ZnSnX 4 (CZTX; X: Group 16 elements), with X being S/Se, have been receiving considerable attention due to their utility as an absorber layer in solar photovoltaics (PV). This paper reports on the synthesis of CZTSe and CZTS nanocrystalline powders at low temperatures, starting from elemental metal and chalcogen powders, via the low cost, scalable technique of ball milling. The prepared samples were well characterized using the different characterization tools. XRD, Raman, SEM and TEM studies confirm the formation of single-phase, stoichiometric, nano-crystalline kesterite CZTS and CZTSe powders. The low temperature phase selection of the complex quaternary compound in this system is seen as a direct consequence of the thermodynamic facilitation, coupled with the capability of mechano-chemical synthesis to aid in overcoming kinetic constraints. The optical bandgap of the various samples of CZTS was observed in the range of 1.4–1.6 eV and corresponding values for CZTSe was observed to be in the range of 1.08–1.18 eV. Our work provides a pathway for developing cheap, scalable, and ink-based techniques for low cost solar PV. - Graphical abstract: Display Omitted - Highlights: • A scalable route for synthesis of near phase pure CZTS/Se nano-crystals has been demonstrated. • Stoichiometric CZTS and CZTSe were synthesized via mechano-chemical synthesis route. • Synthesis at near room temperature is supported by thermodynamic calculations

  3. Synthesis of some calcium phosphate crystals using the useful biomass for immobilization of microorganisms

    International Nuclear Information System (INIS)

    Kohiruimaki, T

    2011-01-01

    Three sources of biomass generated by primary industry were used as the raw material for the synthesis of calcium phosphate crystals. Phosphoric acid was extracted from burned rice chaff using a 30% nitric acid solution, while scallop shells and gypsum of plasterboard were used as calcium sources. The calcium phosphate crystals were synthesized by a method involving homogeneous precipitation, and the relationship between the composition and shape of the crystals and the pH at the time of the precipitation was investigated. Monetite crystals in a petal form with a diameter ranging from 0.1 to 2 μm were precipitated at pH 2.0, while granular apatite crystals with a mean diameter of 1 μm were precipitated at pH 6.0. We also investigated the ability of the synthesized calcium phosphate crystals to immobilize lactic acid bacteria for practical use in industrial bioreactor. It was determined that monetite crystals with a diameter of 2 μm had the highest ability to fix lactic acid bacteria. The population of lactic acid bacteria was estimated to exceed 1,300 bacteria per crystal surface of 50 μm 2 suggesting that these crystals may be of practical use in industrial fermenters.

  4. Negative Refraction Angular Characterization in One-Dimensional Photonic Crystals

    OpenAIRE

    Lugo, Jesus Eduardo; Doti, Rafael; Faubert, Jocelyn

    2011-01-01

    Background Photonic crystals are artificial structures that have periodic dielectric components with different refractive indices. Under certain conditions, they abnormally refract the light, a phenomenon called negative refraction. Here we experimentally characterize negative refraction in a one dimensional photonic crystal structure; near the low frequency edge of the fourth photonic bandgap. We compare the experimental results with current theory and a theory based on the group velocity de...

  5. Synthesis and characterization of ceramics BNO (BiNbO4) added to 10% of CuO

    International Nuclear Information System (INIS)

    Sales, A.J.M.; Silva, P.M.O.; Rodrigues Junior, C.A.; Sombra, A.S.B.

    2012-01-01

    The study of the synthesis and structural characterization of ceramic BiNbO4 and behavior of density when added 10% by weight of CuO, with a view to applications in ceramic capacitors, are presented in this work. The BiNbO4 was prepared by conventional ceramic method. The milled powders were calcined for 2 hours at 850 °C for 3 hours and characterized by using a diffractometer Rigaku DMAXB of Co-α radiation. A more detailed characterization by XRD was performed using the program DBWS9807a using the Rietveld refinement of crystal structures, which confirmed the achievement of the α-BNO phase with orthorhombic structure. Were produced buks with the calcined powder, they were sintered at 925 °C. In order to study the grain morphology and distribution of pores in the ceramic body, the surface of the sample by adding 10% of CuO was analyzed by Scanning Electron Microscopy which confirmed a better densification. (author)

  6. Synthesis and characterization of BNO (BiNbO4) ceramics added to 3% of ZnO

    International Nuclear Information System (INIS)

    Sales, A.J.M.; Pires Junior, G.F.M.; Rodrigues, H.O.; Sousa, D.G.; Sales, J.C.; Sombra, A.S.B.

    2012-01-01

    This work describes the synthesis and study of the structural characterization of ceramic BiNbO4 and density behavior when added 3% by weight of ZnO with a view to use in capacitors. The manufacture of BiNbO4 was made by conventional ceramic method. The powders were milled for two hours, calcined at 850 ° C for 3 h and characterized by XRD with Diffractometer Rigaku DMAXB of Co-α radiation. A more detailed XRD characterization was performed with the program DBWS9807a using the Rietveld refinement of crystal structures, which confirmed the achievement of phase -α-BiNbO4. Were made 'buks' with the calcined powder and these were sintered at 1025 ° C. In order to study the grain morphology and distribution of pores in the ceramic body, the surface of the sample with addition of 3% by weight of ZnO was analyzed by Scanning Electron Microscopy which confirmed a better densification. (author)

  7. An alternative gas sensor material: Synthesis and electrical characterization of SmCoO3

    International Nuclear Information System (INIS)

    Michel, Carlos Rafael; Delgado, Emilio; Santillan, Gloria; Martinez, Alma H.; Chavez-Chavez, Arturo

    2007-01-01

    Single-phase perovskite SmCoO 3 was prepared by a wet-chemical synthesis technique using metal-nitrates and citric acid; after its characterization by thermal analyses and X-ray diffraction, sintering at 900 deg. C in air, gave single phase and well crystallized powders. The powders were mixed with an organic solvent to prepare a slurry, which was deposited on alumina substrates as thick films, using the screen-printing technique. Electrical and gas sensing properties of sintered SmCoO 3 films were investigated in air, O 2 and CO 2 , the results show that sensitivity reached a maximum value at 420 deg. C, for both gases. Dynamic tests revealed a better behavior of SmCoO 3 in CO 2 than O 2 , due to a fast response and a larger electrical resistance change to this gas. X-ray diffraction made on powders after electrical characterization in gases, showed that perovskite-type structure was preserved

  8. Synthesis and characterization of branched fcc/hcp ruthenium nanostructures and their catalytic activity in ammonia borane hydrolysis

    KAUST Repository

    AlYami, Noktan; LaGrow, Alec P; Anjum, Dalaver H.; Guan, Chao; Miao, Xiaohe; Sinatra, Lutfan; Yuan, Ding-Jier; Mohammed, Omar F.; Huang, Kuo-Wei; Bakr, Osman

    2018-01-01

    Several systems have shown the ability to stabilize uncommon crystal structures during the synthesis of metallic nanoparticles. By tailoring the nanoparticle crystal structure, the physical and chemical properties of the particles can also

  9. Metal–organic coordination architectures of tetrazole heterocycle ligands bearing acetate groups: Synthesis, characterization and magnetic properties

    International Nuclear Information System (INIS)

    Hu, Bo-Wen; Zheng, Xiang-Yu; Ding, Cheng

    2015-01-01

    Two new coordination complexes with tetrazole heterocycle ligands bearing acetate groups, [Co(L) 2 ] n (1) and [Co 3 (L) 4 (N 3 ) 2 ·2MeOH] n (2) (L=tetrazole-1-acetate) have been synthesized and structurally characterized. Single crystal structure analysis shows that the cobalt-complex 1 has the 3D 3,6-connected (4 2 .6) 2 (4 4 .6 2 .8 8 .10)-ant topology. By introducing azide in this system, complex 2 forms the 2D network containing the [Co 3 ] units. And the magnetic properties of 1 and 2 have been studied. - Graphical abstract: The synthesis, crystal structure, and magnetic properties of the new coordination complexes with tetrazole heterocycle ligands bearing acetate groups are reported. - Highlights: • Two novel Cobalt(II) complexes with tetrazole acetate ligands were synthesized. • The magnetic properties of two complexes were studied. • Azide as co-ligand resulted in different structures and magnetic properties. • The new coordination mode of tetrazole acetate ligand was obtained.

  10. Synthesis, Spectroscopic and DFT Characterization of 4â-(4-tert ...

    African Journals Online (AJOL)

    In this work the synthesis, spectral characterization and non-linear optical properties of metal-free .... following literature methods23–26 The advantage of this method ..... Synthesis of phthalocyanine conjugates with gold nanoparticles and.

  11. Advances in the Growth and Characterization of Relaxor-PT-Based Ferroelectric Single Crystals

    Directory of Open Access Journals (Sweden)

    Jun Luo

    2014-07-01

    Full Text Available Compared to Pb(Zr1−xTixO3 (PZT polycrystalline ceramics, relaxor-PT single crystals offer significantly improved performance with extremely high electromechanical coupling and piezoelectric coefficients, making them promising materials for piezoelectric transducers, sensors and actuators. The recent advances in crystal growth and characterization of relaxor-PT-based ferroelectric single crystals are reviewed in this paper with emphases on the following topics: (1 the large crystal growth of binary and ternary relaxor-PT-based ferroelectric crystals for commercialization; (2 the composition segregation in the crystals grown from such a solid-solution system and possible solutions to reduce it; (3 the crystal growth from new binary and ternary compositions to expand the operating temperature and electric field; (4 the crystallographic orientation dependence and anisotropic behaviors of relaxor-PT-based ferroelectriccrystals; and (5 the characterization of the dielectric, elastic and piezoelectric properties of the relaxor-PT-based ferroelectriccrystals under small and large electric fields.

  12. Structural and morphological characterization of fullerite crystals prepared from the vapor phase

    International Nuclear Information System (INIS)

    Haluska, M.; Fejdi, P.; Vybornov, M.; Kuzmany, H.

    1993-01-01

    Crystal structure, habits and surface structures of fullerite crystals prepared from vapor phase were characterized by X-ray analysis, interfacial angle measurements and optical and scanning electron microscopy (SEM). The study of selected C 60 crystals confirmed the fcc structure at room temperature. The crystal habit is determined by two types of morphological faces, namely {100} and {111}. SEM was used for the observation of thermal etched surfaces. (orig.)

  13. Synthesis and growth of single crystals of PrCl3

    International Nuclear Information System (INIS)

    Pei, Jen Shieh.

    1984-01-01

    An efficient method for growth of high optical quality single crystals of PrCl 3 . The method consists in careful drying of the hydrated chloride, PrCl 3 . 7H 2 O, with a protective atmosphere of anhydrous HCl and Ar. A subsequent growth was done by the zone melting technique. The hydrated chloride had prepared from dissolution of the oxide Pr 6 O 11 in hydrochloric acid. The grown crystals had characterized fluorescence and x-ray diffraction measurements. (Author) [pt

  14. Controlled synthesis of high-quality crystals of monolayer MoS2 for nanoelectronic device application

    DEFF Research Database (Denmark)

    Yang, Xiaonian; Li, Qiang; Hu, Guofeng

    2016-01-01

    . Monolayer MoS2 so far can be obtained by mechanical exfoliation or chemical vapor deposition (CVD). However, controllable synthesis of large area monolayer MoS2 with high quality needs to be improved and their growth mechanism requires more studies. Here we report a systematical study on controlled...... synthesis of high-quality monolayer MoS2 single crystals using low pressure CVD. Large-size monolayer MoS2 triangles with an edge length up to 405 mu m were successfully synthesized. The Raman and photoluminescence spectroscopy studies indicate high homogenous optical characteristic of the synthesized...... monolayer MoS2 triangles. The transmission electron microscopy results demonstrate that monolayer MoS2 triangles are single crystals. The back-gated field effect transistors (FETs) fabricated using the as-grown monolayer MoS2 show typical n-type semiconductor behaviors with carrier mobility up to 21.8 cm(2...

  15. Zinc(II) halide complexes with 2-methoxyaniline ligand: Synthesis, characterization, thermal analyses, crystal structure determination and luminescent properties

    Science.gov (United States)

    Amani, Vahid

    2018-03-01

    Three new mononuclear zinc(II) complexes, [Zn(2-MeO-C6H4NH2)2X2] (X is Cl in 1, Br in 2 and I in 3), were prepared from the reactions of ZnX2 with 2-methoxyaniline (2-MeO-C6H4NH2) ligand in methanol. Suitable crystals of these complexes were obtained for X-ray diffraction measurements by slow evaporation of methanol solution at room temperature. The three complexes were thoroughly characterized by thermogravimetric analysis, elemental analysis (CHNO), spectral methods (IR, UV-Vis, 13C{1H}NMR, 1H NMR and luminescence), and single crystal X-ray diffraction. The X-ray structural analysis indicated that in the structures of these complexes, the zinc(II) cation is four-coordinated in a distorted tetrahedral configuration by two N atoms from two 2-methoxyanyline ligands and two halide anions. Also, in these complexes intermolecular interactions, for example Nsbnd H⋯X hydrogen bonds (in 1-3), Csbnd H⋯X hydrogen bonds (in 3), Csbnd H⋯π interactions (in 1 and 2) and π⋯π interactions (in 3), are effective in the stabilization of the crystal structures. In addition, the luminescence spectra of all complexes in methanolic solution show that the intensity of their emission bands is stronger than that for free 2-methoxyaniline ligand.

  16. The facile and low temperature synthesis of nanophase hydroxyapatite crystals using wet chemistry

    International Nuclear Information System (INIS)

    Dhand, Vivek; Rhee, K.Y.; Park, Soo-Jin

    2014-01-01

    A simple and facile wet chemistry route was used to synthesize nanophase hydroxyapatite (HaP) crystals at low temperature. The synthesis was carried out at a pH of 11.0 and at a temperature of 37 °C. The resulting samples were washed several times and subjected to further analysis. XRD studies revealed that the HaP crystals were polycrystalline in nature with a crystallite size of ∼ 15–60 ± 5 nm. SEM-EDXA images confirmed the presence of calcium (Ca), phosphorous (P), and oxygen (O) peaks. Likewise, FTIR confirmed the presence of characteristic phosphate and hydroxyl peaks in samples. Lastly, HRTEM images clearly showed distinctive lattice fringes positioned in the 100 and 002 planes. TGA analysis shows that HaP crystals can withstand higher calcination temperatures and are thermally stable. - Highlights: • Facile and low temperature nanophase HaP crystals synthesized at pH 11 and 37 °C • Electron microscopy image of HaP shows characteristic rice grain like morphology. • FTIR results show the characteristic and fingerprint functional groups of HaP. • Thermal stability of HaP crystals up to 500 °C • Growth of Hap crystals occur parallel to c-axis and a possible mechanism proposed

  17. The RMgSn{sub 2} series of compounds (R = rare earth metal). Synthesis, crystal structure, and magnetic measurements

    Energy Technology Data Exchange (ETDEWEB)

    Solokha, Pavlo; Minetti, Riccardo; De Negri, Serena; Saccone, Adriana [Dipartimento di Chimica e Chimica Industriale, Universita di Genova (Italy); Pereira, Laura Cristina J.; Goncalves, Antonio P. [Centro de Ciencias e Tecnologias Nucleares, Instituto Superior Tecnico, EN 10, Universidade de Lisboa, Bobadela (Portugal)

    2017-06-30

    The novel isostructural series of phases RMgSn{sub 2} (R = Y, La-Nd, Sm, Gd-Tm, Lu) is presented. They were prepared by direct synthesis in an induction furnace and subsequently annealed at 500 C. Their crystal structures were determined through single-crystal X-ray diffraction analysis of the Ce representative [I anti 42m, tI32-LaMgSn{sub 2}, Z = 8, a = 0.82863(3) nm, c = 1.23129(5) nm] and confirmed by powder X-ray diffraction analysis of the other members of the series. Rietveld refinements were also performed on the homologues with R = Pr, Tm, and Y. The title phases show a unique space distribution of atoms, characterized by the presence of a Sn-Sn dumbbell distanced at around 0.29 nm. Their structures are related to those of a few binary AeTt{sub 3} (Ae = alkaline earth; Tt = Si, Ge; I4/mmm, tI32-YbSi{sub 3}) compounds that are stable at high pressure, characterized by a more complex 3D covalently bonded Tt network. Compounds CeMgSn{sub 2} and TbMgSn{sub 2} were magnetically characterized; they show paramagnetic behavior with the presence of ferromagnetic interactions, more pronounced in the case of TbMgSn{sub 2}, as suggested by the Curie-Weiss temperatures, determined in the high-temperature range, of 0.96 and 27.6 K for CeMgSn{sub 2} and TbMgSn{sub 2}, respectively. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  18. Photonic crystals based on opals and inverse opals: synthesis and structural features

    International Nuclear Information System (INIS)

    Klimonsky, S O; Abramova, Vera V; Sinitskii, Alexander S; Tretyakov, Yuri D

    2011-01-01

    Methods of synthesis of photonic crystals based on opals and inverse opals are considered. Their structural features are discussed. Data on different types of structural defects and their influence on the optical properties of opaline materials are systematized. The possibilities of investigation of structural defects by optical spectroscopy, electron microscopy, microradian X-ray diffraction, laser diffraction and using an analysis of Kossel ring patterns are described. The bibliography includes 253 references.

  19. Synthesis and characterization of dextran-coated iron oxide nanoparticles

    Science.gov (United States)

    Predescu, Andra Mihaela; Matei, Ecaterina; Berbecaru, Andrei Constantin; Pantilimon, Cristian; Drăgan, Claudia; Vidu, Ruxandra; Predescu, Cristian; Kuncser, Victor

    2018-03-01

    Synthesis and characterization of iron oxide nanoparticles coated with a large molar weight dextran for environmental applications are reported. The first experiments involved the synthesis of iron oxide nanoparticles which were coated with dextran at different concentrations. The synthesis was performed by a co-precipitation technique, while the coating of iron oxide nanoparticles was carried out in solution. The obtained nanoparticles were characterized by using scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction spectrometry, Fourier transform infrared spectroscopy and superconducting quantum interference device magnetometry. The results demonstrated a successful coating of iron oxide nanoparticles with large molar weight dextran, of which agglomeration tendency depended on the amount of dextran in the coating solution. SEM and TEM observations have shown that the iron oxide nanoparticles are of about 7 nm in size.

  20. Study On The Synthesis Of Disida Derivatives For Labeling With 99mTc

    International Nuclear Information System (INIS)

    Pham Ngoc Dien; Duong Van Dong; Nguyen Thi Thu; Bui Van Cuong; Mai Phuoc Tho; Vo Cam Hoa

    2007-01-01

    This study describes the synthesis method and characterization of 2,6-Diisopropyl acetanilide iminodiacetic acid (DISIDA). DISIDA is synthesized by replacement reaction of two Clo atoms in chloroacetyl chloride molecule. The synthesis process has two steps. Step1: The synthesis of 2,6-diisopropylacetanilide; Step 2: The synthesis of DISIDA. The good result obtained in the step 1 reaction, it was carried out in the low pH i.e acid medium. The synthesis reaction achieved high performance at room temperature for 2 hours. The product was crystallized completely while adding in mixture reaction amount sodium acetate by drop wise and stir slowly. The step 2 reaction was carried out in medium of alkali (pH = 10-12), reaction temperature was 50 o C - 60 o C, reaction time during 8 hours. After that EtOH was evaporated by vacuum and compound was crystallized with pH = 2-3, in cool medium ( o C ). Raw material was recrystallized many time by cool EtOH. Pure product (DISIDA ) was characterized by IR, LC/MS, HPLC spectroscopy, melting point, crystal picture. Synthesized DISIDA, when tagged with diagnostic radionuclides such as 99m Tc are quite good, 99m Tc-DISIDA Complexes with RC purity and labeling efficiency >98% and above could be prepared by ordinary reaction condition, that reason can apply for valuation of possibility and reality on different purposes. (author)

  1. Sonocrystallization—Case Studies of Salicylamide Particle Size Reduction and Isoniazid Derivative Synthesis and Crystallization

    Directory of Open Access Journals (Sweden)

    Zhen-Yu Yang

    2018-06-01

    Full Text Available Two case studies of salicylamide particle size reduction and isoniazid derivative synthesis and crystallization realized using sonocrystallization were investigated. The size, habit, structure, thermal behavior, and spectrometric properties of sonocrystallized crystals were analyzed through scanning electron microscopy (SEM, powder X-ray diffractometry (PXRD, differential scanning calorimetry (DSC, and Fourier transform infrared (FTIR spectroscopy. The effects of the operating parameters, such as sonication intensity, sonication duration, and solution concentration, on sonocrystallization were compared. The crystal size of salicylamide was reduced from 595 μm (the original size and was efficiently manipulated to be between 40 and 80 μm. Moreover, compared with the crystal habits of unprocessed crystals and recrystallized crystals fabricated through conventional methods, the crystal habit of salicylamide could be modified to present a regular shape. The structure, thermal behavior, and spectrometric properties of sonocrystallized salicylamide were found to be in agreement with those of an unprocessed sample. For producing isoniazid derivative crystals, N′-(propan-2-ylidene-isonicotinohydrazide was synthesized using isoniazid in acetone at 318 K. The resulting solution was then cooled by applying power ultrasound to isolate N′-(propan-2-ylidene-isonicotinohydrazide crystals. The solid-state properties of the synthesized N′-(propan-2-ylidene-isonicotinohydrazide was verified through PXRD, DSC, and FTIR spectroscopy. The feasibility of particle size manipulation was then demonstrated through sonocrystallization.

  2. Synthesis, crystal structure and biological activity of novel diester cyclophanes

    International Nuclear Information System (INIS)

    Zhang, Pengfei; Yang, Bingqin; Fang, Xianwen; Cheng, Zhao; Yang, Meipan

    2012-01-01

    A series of novel diester cyclophanes was synthesized by esterification of 1,2-benzenedicarbonyl chloride with eight different diols under high dilution conditions. The structures of the compounds were verified by elemental analysis, 1 H nuclear magnetic resonance (NMR), IR spectroscopy and high resolution mass spectrometry (HRMS). The crystal structures of two compounds were characterized by single crystal X-ray diffractometry (XRD). All the new cyclophanes were evaluated for biological activities and the results showed that some of these compounds have low antibacterial or antifungal activities (author)

  3. Synthesis, growth, and studies (crystal chemistry, magnetic chemistry) of actinide-based intermetallic compounds and alloys with a 1.1.1 stoichiometry

    International Nuclear Information System (INIS)

    Kergadallan, Yann

    1993-01-01

    The first part of this research thesis reports the study of the synthesis and reactivity of intermetallic compounds with a 1.1.1 stoichiometry. It presents the thermal properties of 1.1.1 compounds: general presentation of physical transitions, and of solid solutions and formation heat, application to actinides (reactivity analysis from phase diagrams, techniques of crystal synthesis and crystal growth. It describes experimental techniques: synthesis, determination of fusion temperature by dilatometry, methods used for crystal growth, characterisation techniques (metallography, X ray diffraction on powders, dilatometry). It discusses the obtained results in terms of characterisation of synthesised samples, of crystal growth, and of measurements of fusion temperature. The second part addresses crystal chemistry studies: structure of compounds with a 1.1.1 stoichiometry (Laves structures, Zr, Ti and Pu compounds), techniques of analysis by X-ray diffraction (on powders and on single crystals), result interpretation (UNiX compounds, AnTAl compounds with T being a metal from group VIII, AnTGa compounds, AnNiGe compounds, distance comparison, structure modifications under pressure). The third part concerns physical issues. The author addresses the following topics: physical properties of intermetallic 1.1.1 compounds (magnetism of yttrium phases, behaviour of uranium-based Laves phases, analysis of pseudo-binary diagrams, physical characteristics of uranium-based 1.1.1 compounds, predictions of physical measurements), analysis techniques (Moessbauer spectroscopy, SQUID for Superconducting Quantum Interference Device), and result interpretation

  4. Recent Advances in Discotic Liquid Crystal-Assisted Nanoparticles

    Directory of Open Access Journals (Sweden)

    Ashwathanarayana Gowda

    2018-03-01

    Full Text Available This article primarily summarizes recent advancement in the field of discotic liquid crystal (DLC nanocomposites. Discotic liquid crystals are nanostructured materials, usually 2 to 6 nm size and have been recognized as organic semiconducting materials. Recently, it has been observed that the dispersion of small concentration of various functionalized zero-, one- and two-dimensional nanomaterials in the supramolecular order of mesophases of DLCs imparts negligible impact on liquid crystalline properties but enhances their thermal, supramolecular and electronic properties. Synthesis, characterization and dispersion of various nanoparticles in different discotics are presented.

  5. Synthesis and characterization of TEP-EDTA-regulated bioactive hydroxyapatite

    Science.gov (United States)

    Haders, Daniel Joseph, II

    Hydroxyapatite (HA), Ca10(PO4)6(OH) 2, the stoichiometric equivalent of the ceramic phase of bone, is the preferred material for hard tissue replacement due to its bioactivity. However, bioinert metals are utilized in load-bearing orthopedic applications due to the poor mechanical properties of HA. Consequently, attention has been given to HA coatings for metallic orthopedic implants to take advantage of the bioactivity of HA and the mechanical properties of metals. Commercially, the plasma spray process (PS-HA) is the method most often used to deposit HA films on metallic implants. Since its introduction in the 1980's, however, concerns have been raised about the consequences of PS-HA's low crystallinity, lack of phase purity, lack of film-substrate chemical adhesion, passivation properties, and difficulty in coating complex geometries. Thus, there is a need to develop inexpensive reproducible next-generation HA film deposition techniques, which deposit high crystallinity, phase pure, adhesive, passivating, conformal HA films on clinical metallic substrates. The aim of this dissertation was to intelligently synthesize and characterize the material and biological properties of HA films on metallic substrates synthesized by hydrothermal crystallization, using thermodynamic phase diagrams as the starting point. In three overlapping interdisciplinary studies the potential of using ethylenediamine-tetraacetic acid/triethyl phosphate (EDTA/TEP) doubly regulated hydrothermal crystallization to deposit HA films, the TEP-regulated, time-and-temperature-dependent process by which films were deposited, and the bioactivity of crystallographically engineered films were investigated. Films were crystallized in a 0.232 molal Ca(NO3)2-0.232 molal EDTA-0.187 molal TEP-1.852 molal KOH-H2O chemical system at 200°C. Thermodynamic phase diagrams demonstrated that the chosen conditions were expected to produce Ca-P phase pure HA, which was experimentally confirmed. EDTA regulation of

  6. RNA Crystallization

    Science.gov (United States)

    Golden, Barbara L.; Kundrot, Craig E.

    2003-01-01

    RNA molecules may be crystallized using variations of the methods developed for protein crystallography. As the technology has become available to syntheisize and purify RNA molecules in the quantities and with the quality that is required for crystallography, the field of RNA structure has exploded. The first consideration when crystallizing an RNA is the sequence, which may be varied in a rational way to enhance crystallizability or prevent formation of alternate structures. Once a sequence has been designed, the RNA may be synthesized chemically by solid-state synthesis, or it may be produced enzymatically using RNA polymerase and an appropriate DNA template. Purification of milligram quantities of RNA can be accomplished by HPLC or gel electrophoresis. As with proteins, crystallization of RNA is usually accomplished by vapor diffusion techniques. There are several considerations that are either unique to RNA crystallization or more important for RNA crystallization. Techniques for design, synthesis, purification, and crystallization of RNAs will be reviewed here.

  7. The Synthesis and Crystal Structure of Two New Hydrazone Compounds

    Directory of Open Access Journals (Sweden)

    Li-Hua Wang

    2016-05-01

    Full Text Available Two new hydrazone compounds, 4-formylimidazole-4-hydroxybenzhydrazone dihydrate (1 and 2-nitrobenzaldehyde-2-furan formylhydrazone (2, were synthesized via the classical synthesis method. Their structure was determined via elemental analysis and X-ray single crystal diffraction analysis. Compound 1 crystallizes in triclinic, space group P-1 with a = 7.0321(14 Å, b = 7.3723(15 Å, c = 13.008(3 Å, α = 98.66(3°, β = 101.69(3°, γ = 92.25(3°, V = 651.2(2 Å3, Z = 2, Dc = 1.358 g·cm−3, μ = 0.106 mm−1, F(000 = 280, and final R1 = 0.0564, wR2 = 0.1420. Compound 2 crystallizes in monoclinic, space group P21/c with a = 17.3618(9 Å, b = 9.1506(4 Å, c = 15.5801(7 Å, β = 104.532(5°, V = 2396.05(19 Å3, Z = 8, Dc = 1.437 g·cm−3, μ = 0.111 mm−1, F(000 = 1072, and final R1 = 0.0633, wR2 = 0.1649. Compound 1 forms a 2D-layered structure via the interactions of 1D chains and Compound 2 forms a 3D network structure via the interactions of 1D chains.

  8. Synthesis and characterization of Gd-doped magnetite nanoparticles

    International Nuclear Information System (INIS)

    Zhang, Honghu; Malik, Vikash; Mallapragada, Surya; Akinc, Mufit

    2017-01-01

    Synthesis of magnetite nanoparticles has attracted increasing interest due to their importance in biomedical and technological applications. Tunable magnetic properties of magnetite nanoparticles to meet specific requirements will greatly expand the spectrum of applications. Tremendous efforts have been devoted to studying and controlling the size, shape and magnetic properties of magnetite nanoparticles. Here we investigate gadolinium (Gd) doping to influence the growth process as well as magnetic properties of magnetite nanocrystals via a simple co-precipitation method under mild conditions in aqueous media. Gd doping was found to affect the growth process leading to synthesis of controllable particle sizes under the conditions tested (0–10 at% Gd"3"+). Typically, undoped and 5 at% Gd-doped magnetite nanoparticles were found to have crystal sizes of about 18 and 44 nm, respectively, supported by X-ray diffraction and transmission electron microscopy. Our results showed that Gd-doped nanoparticles retained the magnetite crystal structure, with Gd"3"+ randomly incorporated in the crystal lattice, probably in the octahedral sites. The composition of 5 at% Gd-doped magnetite was Fe_(_3_−_x_)Gd_xO_4 (x=0.085±0.002), as determined by inductively coupled plasma mass spectrometry. 5 at% Gd-doped nanoparticles exhibited ferrimagnetic properties with small coercivity (~65 Oe) and slightly decreased magnetization at 260 K in contrast to the undoped, superparamagnetic magnetite nanoparticles. Templation by the bacterial biomineralization protein Mms6 did not appear to affect the growth of the Gd-doped magnetite particles synthesized by this method. - Highlights: • Gd-doped magnetite nanoparticles are synthesized via aqueous co-precipitation method under mild conditions. • Gd doping affects growth of magnetite nanoparticles leading to tunable particle size. • Gd-doped magnetite nanoparticles exhibit ferrimagnetic properties.

  9. Synthesis and characterization of magnetite nanoparticles coated with lauric acid

    Energy Technology Data Exchange (ETDEWEB)

    Mamani, J.B., E-mail: javierbm@einstein.br [Instituto do Cérebro-InCe, Hospital Israelita Albert Einstein-HIAE, 05651-901 São Paulo (Brazil); Costa-Filho, A.J. [Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto (Brazil); Cornejo, D.R. [Instituto de Física Universidade de São Paulo, USP, São Paulo (Brazil); Vieira, E.D. [Instituto de Física, Universidade Federal de Goiás, Goiânia (Brazil); Gamarra, L.F. [Instituto do Cérebro-InCe, Hospital Israelita Albert Einstein-HIAE, 05651-901 São Paulo (Brazil)

    2013-07-15

    Understanding the process of synthesis of magnetic nanoparticles is important for its implementation in in vitro and in vivo studies. In this work we report the synthesis of magnetic nanoparticles made from ferrous oxide through coprecipitation chemical process. The nanostructured material was coated with lauric acid and dispersed in aqueous medium containing surfactant that yielded a stable colloidal suspension. The characterization of magnetic nanoparticles with distinct physico-chemical configurations is fundamental for biomedical applications. Therefore magnetic nanoparticles were characterized in terms of their morphology by means of TEM and DLS, which showed a polydispersed set of spherical nanoparticles (average diameter of ca. 9 nm) as a result of the protocol. The structural properties were characterized by using X-ray diffraction (XRD). XRD pattern showed the presence of peaks corresponding to the spinel phase of magnetite (Fe{sub 3}O{sub 4}). The relaxivities r{sub 2} and r{sub 2}* values were determined from the transverse relaxation times T{sub 2} and T{sub 2}* at 3 T. Magnetic characterization was performed using SQUID and FMR, which evidenced the superparamagnetic properties of the nanoparticles. Thermal characterization using DSC showed exothermic events associated with the oxidation of magnetite to maghemite. - Highlights: • Synthesis of magnetic nanoparticles coated with lauric acid • Characterization of magnetic nanoparticles • Morphological, structural, magnetic, calorimetric and relaxometric characterization.

  10. Synthesis and characterization of rare-earth-doped calcium tungstate nanocrystals

    Science.gov (United States)

    Suneeta, P.; Rajesh, Ch.; Ramana, M. V.

    2018-02-01

    In this paper, we report synthesis and characterization of rare-earth-ion-doped calcium tungstate (CaWO4) nanocrystals (NCs). Rare-earth ions, such as gadolinium (Gd), neodymium (Nd), praseodymium (Pr), samarium (Sm) and holmium (Ho), were successfully doped in the CaWO4 NCs by changing the synthesis conditions. The adopted synthesis route was found to be fast and eco-friendly. Structural characterizations, such as X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and compositional analysis, were performed using energy dispersive analysis of X-rays (EDAX) on as-synthesized NCs. The results indicate the size of the NCs ranging between 47 to 68nm and incorporation of rare-earth ions in CaWO4 NCs.

  11. Synthesis and crystal structure of the rare earth borogermanate EuGeBO{sub 5}

    Energy Technology Data Exchange (ETDEWEB)

    Chi, Yang; Zhuang, Yan; Guo, Sheng-Ping [Yangzhou Univ., Jiangsu (China). College of Chemistry and Chemical Engineering

    2017-03-01

    The synthesis and crystal structure of the rare earth borogermanate EuGeBO{sub 5} are reported. It is synthesized by high-temperature solid-state reaction and crystallizes in the monoclinic space group P2{sub 1}/c (no. 14) with the unit cell parameters a=4.8860(5), b=7.5229(8), c=9.9587(10) Aa, and β=91.709(3) . Its crystal structure features a polyanion-type layer (GeBO{sub 5}){sup 3-} constructed by BO{sub 4} and GeO{sub 4} tetrahedra connected alternatingly. Eu{sup 3+} ions are located in cavities and are coordinated by eight O atoms. Various structures of the related compounds REMM'O{sub 5} (RE=rare earth metal; M=Si, Ge, and Sn; M'=B, Al, and Ga) are also discussed.

  12. Towards the synthesis of an experimental bioactive dental ceramic. Part I: Crystallinity characterization and bioactive behavior evaluation

    International Nuclear Information System (INIS)

    Goudouri, O.-M.; Kontonasaki, E.; Papadopoulou, L.; Kantiranis, N.; Lazaridis, N.K.; Chrissafis, K.; Chatzistavrou, X.; Koidis, P.; Paraskevopoulos, K.M.

    2014-01-01

    An attachment between the dental ceramic and the surrounding marginal tissues in fixed prosthetic restorations could eliminate secondary carries prevalence. The development of dental ceramics with apatite forming ability could provide the biological surface required for selective spread and attachment of specific cell types able to promote tissue attachment. Dental ceramics/bioactive glass composites synthesized by the sol gel method have been previously reported to develop carbonated hydroxyapatite (HCAp) in biomimetic solutions, requiring though a high amount of bioactive glass, which resulted in the compromise of their mechanical integrity. Thus, the aim of the present work was the synthesis and characterization of an experimental sol–gel derived dental ceramic with low amount of bioactive glass and the evaluation of its in vitro bioactivity. Differential thermal and thermogravimetric analysis (TG–DTA), Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffractometry (XRD), Scanning Electron Microscopy (SEM) and Energy Dispersive Spectroscopy (EDS) were used to evaluate the crystal structure and the in vitro apatite forming ability of the synthesized material. The results of this study indicated the successful sol–gel synthesis of an experimental dental ceramic containing low amount of bioactive glass that presented similar structural and morphological characteristics with a commercial feldspathic dental ceramic, while exhibiting in vitro bioactivity. The apatite forming ability of the experimental sol–gel derived feldspathic dental ceramic may trigger the appropriate cellular mechanisms towards the establishment of attachment with the surrounding connective tissue. This attachment could provide a barrier to oral bacteria penetration, prolonging the life expectation of the restorations. - Highlights: • Synthesis of a bioactive sol–gel dental ceramic for fixed prosthetic restorations. • The sol–gel technique promoted the crystallization of

  13. Towards the synthesis of an experimental bioactive dental ceramic. Part I: Crystallinity characterization and bioactive behavior evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Goudouri, O.-M. [Physics Department, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece); Kontonasaki, E. [School of Dentistry, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece); Papadopoulou, L.; Kantiranis, N. [Department of Geology, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece); Lazaridis, N.K. [Chemistry Department, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece); Chrissafis, K.; Chatzistavrou, X. [Physics Department, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece); Koidis, P. [School of Dentistry, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece); Paraskevopoulos, K.M., E-mail: kpar@auth.gr [Physics Department, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece)

    2014-05-01

    An attachment between the dental ceramic and the surrounding marginal tissues in fixed prosthetic restorations could eliminate secondary carries prevalence. The development of dental ceramics with apatite forming ability could provide the biological surface required for selective spread and attachment of specific cell types able to promote tissue attachment. Dental ceramics/bioactive glass composites synthesized by the sol gel method have been previously reported to develop carbonated hydroxyapatite (HCAp) in biomimetic solutions, requiring though a high amount of bioactive glass, which resulted in the compromise of their mechanical integrity. Thus, the aim of the present work was the synthesis and characterization of an experimental sol–gel derived dental ceramic with low amount of bioactive glass and the evaluation of its in vitro bioactivity. Differential thermal and thermogravimetric analysis (TG–DTA), Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffractometry (XRD), Scanning Electron Microscopy (SEM) and Energy Dispersive Spectroscopy (EDS) were used to evaluate the crystal structure and the in vitro apatite forming ability of the synthesized material. The results of this study indicated the successful sol–gel synthesis of an experimental dental ceramic containing low amount of bioactive glass that presented similar structural and morphological characteristics with a commercial feldspathic dental ceramic, while exhibiting in vitro bioactivity. The apatite forming ability of the experimental sol–gel derived feldspathic dental ceramic may trigger the appropriate cellular mechanisms towards the establishment of attachment with the surrounding connective tissue. This attachment could provide a barrier to oral bacteria penetration, prolonging the life expectation of the restorations. - Highlights: • Synthesis of a bioactive sol–gel dental ceramic for fixed prosthetic restorations. • The sol–gel technique promoted the crystallization of

  14. Synthesis and Characterization of Fe3O4 Nanoparticles using Polyvinyl Alcohol (PVA) as Capping Agent and Glutaraldehyde (GA) as Crosslinker

    Science.gov (United States)

    Budi Hutami Rahayu, Lale; Oktavia Wulandari, Ika; Herry Santjojo, Djoko; Sabarudin, Akhmad

    2018-01-01

    The use of polyvinyl alcohol (PVA) as a capping agent and glutaraldehyde (GA) as a crosslinker for a synthesis of magnetite (Fe3O4) nanoparticles is able to reduce agglomeration of produced Fe3O4. Additionally, oxidation of Fe3O4 by air could be avoided. The synthesis is carried out in two steps: first step, magnetite (Fe3O4) nanoparticles were prepared by dissolving the FeCl3.6H2O and FeCl2.4H2O in alkaline media (NH3.H2O). The second step, magnetite nanoparticles were coated with polyvinyl alcohol (PVA) and glutaraldehyde (GA) to obtain Fe3O4-PVA-GA. The latter material was then characterized by FTIR to determine the typical functional groups of magnetite coated with PVA-GA. X-ray Diffraction analysis was used to determine structure and size of crystal as well as the percentage of magnetite produced. It was found that the produced nanoparticles have crystal sizes around 4-9 nm with the cubic crystal structure. The percentage of magnetite phase increases when the amount of glutaraldehyde increased. SEM-EDX was employed to assess the surface morphology and elemental composition of the resulted nanoparticles. The magnetic character of the magnetite and Fe3O4- PVA-GA were studied using Electron Spin Resonance.

  15. Synthesis, characterization and mechanistic insights of mycogenic iron oxide nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Bhargava, Arpit; Jain, Navin; Manju Barathi L [Birla Institute of Technology and Science, Centre for Biotechnology, Department of Biological Sciences (India); Akhtar, Mohd Sayeed [Jimma University, Department of Applied Microbiology, College of Natural Sciences (Ethiopia); Yun, Yeoung-Sang [Chonbuk National University, Division of Environmental and Chemical Engineering (Korea, Republic of); Panwar, Jitendra, E-mail: drjitendrapanwar@yahoo.co.in [Birla Institute of Technology and Science, Centre for Biotechnology, Department of Biological Sciences (India)

    2013-11-15

    In the present study, extracellular synthesis of iron oxide nanoparticles (IONPs) was achieved using Aspergillus japonicus isolate AJP01. The isolate demonstrated its ability to hydrolyze the precursor salt solution, a mixture of iron cyanide complexes, under ambient conditions. Hydrolysis of these complexes released ferric and ferrous ions, which underwent protein-mediated coprecipitation and controlled nucleation resulting in the formation of IONPs. Transmission electron microscopy, selected area electron diffraction pattern, energy dispersive spectroscopy and grazing incidence X-ray diffraction analysis confirmed the mycosynthesis of IONPs. The synthesized particles were cubic in shape with a size range of 60–70 nm with crystal structure corresponding to magnetite. Scanning electron microscopy analysis revealed the absence of IONPs on fungal biomass surface, indicating the extracellular nature of synthesis. Fourier transform infrared spectroscopy confirmed the presence of proteins on as-synthesised IONPs, which may confer their stability. Preliminary investigation indicated the role of proteins in the synthesis and stabilization of IONPs. On the basis of present findings, a probable mechanism for synthesis of IONPs is suggested. The simplicity and versatility of the present approach can be utilized for the synthesis of other nanomaterials.

  16. Synthesis, crystal structure and biological activity of novel diester cyclophanes

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Pengfei; Yang, Bingqin; Fang, Xianwen; Cheng, Zhao; Yang, Meipan, E-mail: yangbq@nwu.edu.cn [Department of Chemistry, Key Laboratory of Synthetic and Natural Functional Molecule Chemistry, Northwest University, Shaanxi (China)

    2012-10-15

    A series of novel diester cyclophanes was synthesized by esterification of 1,2-benzenedicarbonyl chloride with eight different diols under high dilution conditions. The structures of the compounds were verified by elemental analysis, {sup 1}H nuclear magnetic resonance (NMR), IR spectroscopy and high resolution mass spectrometry (HRMS). The crystal structures of two compounds were characterized by single crystal X-ray diffractometry (XRD). All the new cyclophanes were evaluated for biological activities and the results showed that some of these compounds have low antibacterial or antifungal activities (author)

  17. Ionic Liquid Crystals: Versatile Materials.

    Science.gov (United States)

    Goossens, Karel; Lava, Kathleen; Bielawski, Christopher W; Binnemans, Koen

    2016-04-27

    This Review covers the recent developments (2005-2015) in the design, synthesis, characterization, and application of thermotropic ionic liquid crystals. It was designed to give a comprehensive overview of the "state-of-the-art" in the field. The discussion is focused on low molar mass and dendrimeric thermotropic ionic mesogens, as well as selected metal-containing compounds (metallomesogens), but some references to polymeric and/or lyotropic ionic liquid crystals and particularly to ionic liquids will also be provided. Although zwitterionic and mesoionic mesogens are also treated to some extent, emphasis will be directed toward liquid-crystalline materials consisting of organic cations and organic/inorganic anions that are not covalently bound but interact via electrostatic and other noncovalent interactions.

  18. Organic compounds containing methoxy and cyanoacrylic acid: Synthesis, characterization, crystal structures, and theoretical studies

    Energy Technology Data Exchange (ETDEWEB)

    Khalaji, A. D., E-mail: alidkhalaji@yahoo.com [Golestan University, Department of Chemistry, Faculty of Science (Iran, Islamic Republic of); Maddahi, E. [Iran University of Science & Technology, Ms.C Educated, Department of Chemistry (Iran, Islamic Republic of); Dusek, M.; Fejfarova, K. [Institute of Physics of the ASCR, v.v.i. (Czech Republic); Chow, T. J. [Academia Sinica, Institute of Chemistry (China)

    2015-12-15

    Metal-free organic compounds 24-SC ((E)-2-cyano-3-(2,4-dimethoxyphenyl)acrylic acid) and 34-SC ((E)-2-cyano-3-(3,4-dimethoxyphenyl)acrylic acid), containing methoxy groups as a donor and the acrylic acid as an acceptor were synthesized and characterized by CHN, FT-IR, UV-Vis, {sup 1}H-NMR and single crystal X-ray diffraction and used as photosensitizers for the application of dye-sensitized solar cells (DSSC). The sensitizing characteristics of them were evaluated. Both compounds contain the natural molecule, its anionic form and the piperidinium cation and they differ by number of these molecules in the asymmetric unit. To get further insight into the effect of molecular structure on the performance of DSSC, their geometry and energies of HOMO and LUMO were optimized by density functional theory calculation at the B3LYP/6-31G(d) level with Gaussian 03. Overall conversion efficiencies of 0.78 under full sunlight irradiation are obtained for DSSCs based on the new metal-free organic dyes 24-SC and 34-SC.

  19. Synthesis, characterization, thermal

    Directory of Open Access Journals (Sweden)

    Selma Bal

    2017-09-01

    Full Text Available This work explains the synthesis of a new azo-Schiff base compound, derived from condensation between N-ethylcarbazole-3-carbaldehyde and 1,3-diaminopropane, followed by azo coupling reaction with the diazonium salt of 2-amino-4-methyl phenol. The newly synthesized azo-Schiff base was further reacted with the acetate salts of Copper, Cobalt and Nickel to give three coordination compounds. All synthesized compounds have been characterized through spectral analysis. The coordination compounds have been examined for their thermal and catalytic features. Good and moderate yields were obtained for the oxidation of styrene and cyclohexene. Thermal features of the ligand and its complexes have been explained and the results obtained have supported the proposed structures.

  20. Synthesis, characterization, and catalytic properties of stable mesoporous molecular sieve MCM-41 prepared from zeolite mordenite

    International Nuclear Information System (INIS)

    Wang Shan; Dou Tao; Li Yuping; Zhang Ying; Li Xiaofeng; Yan Zichun

    2004-01-01

    Mesoporous molecular sieves (denoted as M-MCM-41) with ordered hexagonal structure have been successfully synthesized from the assembly of precursors from preformed zeolite Mordenite with CTAB surfactant micelle in alkaline media. The samples were characterized by XRD, N 2 adsorption, IR and DTG. The materials exhibit highly hydrothermal stability, as compared with conventional MCM-41. Characterization results indicate that the mesoporous walls of M-MCM-41 contain the secondary building units similar to those in microporous crystal of zeolite Mordenite. In catalytic dealkylation of C10 + aromatic hydrocarbon, M-MCM-41 shows higher activities in comparison with Mordenite and MCM-41, which would be ascribed to the combination of advantages of both MCM-41 (large pores) and Mordenite (strong acidity). Furthermore, this synthesis strategy could be used as a new general method for the preparation of hydrothermally stable mesoporous aluminosilicate materials under alkaline conditions

  1. Synthesis and Characterization of Nanostructured Nickel Diselenide NiSe2 from the Decomposition of Nickel Acetate, (CH3CO2)2Ni

    OpenAIRE

    Yin, Ming; O’Brien, Stephen

    2014-01-01

    Solution processed NiSe2 nanorods were synthesized by a modified colloidal synthesis technique, by chemical reaction of TOPSe and nickel acetate at 150°C. The rods exist as an oleic acid ligand stabilized solution, with oleic acid acting as a capping group. Structural characterization by X-ray diffraction and transmission electron microscopy indicates that the particles are rod-like shaped crystals with a high and relatively constant aspect ratio (30 : 1). TEM shows that the width and the len...

  2. Single crystal growth of yttrium calcium oxy borate (YCOB) crystals by flux technique and their characterization. CP-3.5

    International Nuclear Information System (INIS)

    Arun Kumar, R.; Senthilkumar, M.; Dhanasekaran, R.

    2007-01-01

    Yttrium calcium oxy borate single crystals were grown by the flux technique for the first time. Polycrystalline YCOB material was prepared by solid state reaction method. Single crystals of YCOB were grown using boron-tri-oxide flux. Several transparent single crystals of dimensions 10 x 5 x 5 mm 3 were obtained. The grown crystals were characterized by powder XRD and UV- VIS-NIR studies. The results of powder XRD confirm the crystalline structure of YCOB. The UV- VIS-NIR transmission spectrum reveals that the crystal is highly transparent (above 75%) from ultraviolet (220 nm) to near IR regions enabling it as a suitable candidate for high power UV applications

  3. Synthesis and crystal structures of multifunctional tosylates as basis for star-shaped poly(2-ethyl-2-oxazolines

    Directory of Open Access Journals (Sweden)

    Richard Hoogenboom

    2010-09-01

    Full Text Available The synthesis of well-defined polymer architectures is of major importance for the development of complex functional materials. In this contribution, we discuss the synthesis of a range of multifunctional star-shaped tosylates as potential initiators for the living cationic ring-opening polymerization (CROP of 2-oxazolines resulting in star-shaped polymers. The synthesis of the tosylates was performed by esterification of the corresponding alcohols with tosyl chloride. Recrystallization of these tosylate compounds afforded single crystals, and the X-ray crystal structures of di-, tetra- and hexa-tosylates are reported. The use of tetra- and hexa-tosylates, based on (dipentaerythritol as initiators for the CROP of 2-ethyl-2-oxazoline, resulted in very slow initiation and ill-defined polymers, which is most likely caused by steric hindrance in these initiators. As a consequence, a porphyrin-cored tetra-tosylate initiator was prepared, which yielded a well-defined star-shaped poly(2-ethyl-2-oxazoline by CROP as demonstrated by SEC with RI, UV and diode-array detectors, as well as by 1H NMR spectroscopy.

  4. Development and characterization of Mn2+-doped MgO nanoparticles by solution combustion synthesis

    Science.gov (United States)

    Basha, Md. Hussain; Gopal, N. O.; Rao, J. L.; Nagabhushana, H.; Nagabhushana, B. M.; Chakradhar, R. P. S.

    2015-06-01

    Mn doped MgO Nanoparticles have been prepared by Solution Combustion Synthesis. The synthesized sample is characterized by X-ray diffraction (XRD), Scanning Electron Microscopy (SEM) and Electron Paramagnetic Resonance (EPR). The prepared MgO:Mn (1 mol%) nano crystals appear to be of simple cubic crystalline phase with lattice parameters a = 4.218(2) Å and cell volume = 74.98 (7) Å3. SEM micrograph of powders show highly porous, many agglomerates with irregular morphology, large voids, cracks and pores. EPR spectrum of the sample at room temperature exhibit an isotropic sextet hyperfine pattern, centered at g=1.99, characteristic if Mn2+ ions with S=I=5/2.The observed g value and the hyperfine value reveal the ionic bonding between Mn2+ and its surroundings.

  5. Development and characterization of Mn2+-doped MgO nanoparticles by solution combustion synthesis

    International Nuclear Information System (INIS)

    Basha, Md. Hussain; Gopal, N. O.; Rao, J. L.; Nagabhushana, H.; Nagabhushana, B. M.; Chakradhar, R. P. S.

    2015-01-01

    Mn doped MgO Nanoparticles have been prepared by Solution Combustion Synthesis. The synthesized sample is characterized by X-ray diffraction (XRD), Scanning Electron Microscopy (SEM) and Electron Paramagnetic Resonance (EPR). The prepared MgO:Mn (1 mol%) nano crystals appear to be of simple cubic crystalline phase with lattice parameters a = 4.218(2) Å and cell volume = 74.98 (7) Å 3 . SEM micrograph of powders show highly porous, many agglomerates with irregular morphology, large voids, cracks and pores. EPR spectrum of the sample at room temperature exhibit an isotropic sextet hyperfine pattern, centered at g=1.99, characteristic if Mn 2+ ions with S=I=5/2.The observed g value and the hyperfine value reveal the ionic bonding between Mn 2+ and its surroundings

  6. Crystal habit, characterization and pharmacological activity of various crystal forms of arteether

    Directory of Open Access Journals (Sweden)

    Renu Chadha

    2011-08-01

    Full Text Available The aim of this study was to investigate and characterize different crystal forms of arteether, a rapidly acting, highly potent antimalarial drug for the treatment of acute Plasmodium falciparum malaria. Six different crystal forms were prepared utilizing various polar and non-polar solvents. Scanning electron microscopy (SEM revealed differences in the surface characteristics of the six forms from those of a commercial sample. Differential scanning calorimetry (DSC revealed the absence of a desolvation endotherm indicating that the forms were neither hydrates nor solvates. Powder X-ray diffraction (PXRD patterns of the forms showed much weaker major peaks than in the commercial sample indicating them to be less crystalline. Solubility and dissolution studies showed that the most amorphous form was the most soluble and possessed the highest antimalarial activity.

  7. Synthesis and characterization of highly triboluminescent doped europium tetrakis compounds

    International Nuclear Information System (INIS)

    Fontenot, Ross S.; Hollerman, William A.; Bhat, Kamala N.; Aggarwal, Mohan D.

    2012-01-01

    One of the most intriguing properties involving crystals is their ability to emit light when fractured. While this property was discovered over 200 years ago, no one has ever been able to come up with a complete theory that can predict the physical principles associated with triboluminescence. However, this has not stopped scientists from coming up with various uses for these materials. One such application is to use these materials as the active element for smart impact sensors that can warn of catastrophic impacts. If these sensors are to become a reality however, the material must emit a bright light when fractured. One of the brightest triboluminescent materials found thus far is europium dibenzoylmethide triethylammonium (EuD 4 TEA). This material was discovered by Hurt in 1966 and is bright enough to be seen in daylight. In 2011, the authors discovered that synthesizing EuD 4 TEA using europium nitrate instead of chloride significantly increased the triboluminescence yield and made the synthesis much easier and more consistent. However, to date, there are few investigations into the effects of dopants on the triboluminescence of EuD 4 TEA. This paper reports the investigation of the effects of various dopants on: (1) The triboluminescent light yield, (2) Crystal size and structure, (3) Synthesis time, and (4) Prompt decay time. Results show that inclusion of dopants during synthesis increases the triboluminescence emission of EuD 4 TEA by 55%, significantly reduces the synthesis time, and controls the decay time. All of these properties can be useful for constructing the first prototype of a customized impact sensor. - Highlights: ► Doped europium dibenzoylmethide triethylammonium (EuD 4 TEA) was synthesized. ► Effects of dopants was studied from EuD 4 TEA during low velocity (<10 m/s) impacts. ► The triboluminescent light yield, decay time, and synthesis time were measured. ► A specially-built drop tower was developed to measure triboluminescence

  8. Synthesis, characterization and antimicrobial activity of mixed ...

    African Journals Online (AJOL)

    Synthesis, characterization and antimicrobial activity of mixed ascorbic acid - nicotinamide metal complexes. ... The result of the antimicrobial studies showed that the mixed complexes have higher inhibitory activity than the original ligands against the tested bacteria and fungi species. KEY WORDS: Ascorbic acid, ...

  9. Supramolecular Cocrystals of Gliclazide: Synthesis, Characterization and Evaluation.

    Science.gov (United States)

    Chadha, Renu; Rani, Dimpy; Goyal, Parnika

    2017-03-01

    To prepare the supramolecular cocrystals of gliclazide (GL, a BCS class II drug molecule) via mechanochemical route, with the goal of improving physicochemical and biopharmaceutical properties. Two cocrystals of GL with GRAS status coformers, sebacic acid (GL-SB; 1:1) and α-hydroxyacetic acid (GL-HA; 1:1) were screened out using liquid assisted grinding. The prepared cocrystals were characterized using thermal and analytical techniques followed by evaluation of antidiabetic activity and pharmacokinetic parameters. The generation of new, single and pure crystal forms was characterized by DSC and PXRD. The crystal structure determination from PXRD revealed the existence of both cocrystals in triclinic (P-1) crystal system. The hydrogen bonded network, determined by material studio was well supported by shifts in FTIR and SSNMR. Both the new solid forms displayed improved solubility, IDR, antidiabetic activity and pharmacokinetic parameters as compared to GL. The improvement in these physicochemical and biopharmaceutical properties corroborated the fact that the supramolecular cocrystallization may be useful in the development of pharmaceutical crystalline materials with interesting network and properties.

  10. Green synthesis, characterization and antibacterial activity of copper ...

    African Journals Online (AJOL)

    Green synthesis, characterization and antibacterial activity of copper nanoparticles using L -ascorbic ... Journal Home > Vol 10, No 3 (2017) > ... In this study, simple, economical, convenient and environmentally-friendly chemical reduction ...

  11. Synthesis and crystal structure of chromium-bearing anhydrous wadsleyite

    Science.gov (United States)

    Sirotkina, E. A.; Bindi, L.; Bobrov, A. V.; Aksenov, S. M.; Irifune, T.

    2018-04-01

    A chromium-bearing wadsleyite (Cr- Wad) was synthesized in the model system Mg2SiO4-MgCr2O4 at 14 GPa and 1600 °C and studied from the chemical and structural point of views. Microprobe data gave the formula Mg1.930Cr0.120Si0.945O4, on the basis of 4 oxygen atoms. The crystal structure has been studied by single-crystal X-ray diffraction. The orthorhombic unit-cell parameters are: a = 5.6909(5) Å, b = 11.4640(10) Å, c = 8.2406(9) Å, V = 537.62(9) Å3, Z = 8. The structure, space group Imma, was refined to R 1 = 5.99% in anisotropic approximation using 1135 reflections with F o > 4σ( F o) and 43 parameters. Chromium was found to substitute for both Mg at the octahedral sites and Si at the tetrahedral site, according to the reaction VIMg2+ + IVSi4+ = VICr3+ + IVCr3+. On the whole, the structural topology is nearly identical to that of pure wadsleyite. The successful synthesis of Cr- Wad may be important for the thermobarometry of mantle phase associations.

  12. Fully automatic characterization and data collection from crystals of biological macromolecules.

    Science.gov (United States)

    Svensson, Olof; Malbet-Monaco, Stéphanie; Popov, Alexander; Nurizzo, Didier; Bowler, Matthew W

    2015-08-01

    Considerable effort is dedicated to evaluating macromolecular crystals at synchrotron sources, even for well established and robust systems. Much of this work is repetitive, and the time spent could be better invested in the interpretation of the results. In order to decrease the need for manual intervention in the most repetitive steps of structural biology projects, initial screening and data collection, a fully automatic system has been developed to mount, locate, centre to the optimal diffraction volume, characterize and, if possible, collect data from multiple cryocooled crystals. Using the capabilities of pixel-array detectors, the system is as fast as a human operator, taking an average of 6 min per sample depending on the sample size and the level of characterization required. Using a fast X-ray-based routine, samples are located and centred systematically at the position of highest diffraction signal and important parameters for sample characterization, such as flux, beam size and crystal volume, are automatically taken into account, ensuring the calculation of optimal data-collection strategies. The system is now in operation at the new ESRF beamline MASSIF-1 and has been used by both industrial and academic users for many different sample types, including crystals of less than 20 µm in the smallest dimension. To date, over 8000 samples have been evaluated on MASSIF-1 without any human intervention.

  13. Synthesis, crystal structure and magnetic properties of U2RuGa8

    International Nuclear Information System (INIS)

    Grin', Yu.N.; Rogl', P.; Aksel'rud, L.G.; Pecharskij, V.K.; Yarmolyuk, Ya.P.

    1988-01-01

    Synthesis of a new uranium intermetallic compound of U 2 RuGa 8 composition was conducted. The compound crystallizes in Ho 2 CoGa 8 structural type, met earlier only in compounds of rare earths. Magnetic susceptibility of the compound is rather high and is practically independent of temperature in 80-300 K range. This feature is typical for paramagnetism of electron gas and testifies to the absence of localized magnetic moments on ruthenium and uranium atoms

  14. Synthesis, electronic transport and optical properties of Si:α-Fe2O3 single crystals

    NARCIS (Netherlands)

    Rettie, A.J.E.; Chemelewski, W.D.; Wygant, B.R.; Lindemuth, J.; Lin, J.F.; Eisenberg, D.; Brauer, C.S.; Johnson, T.J.; Beiswenger, T.N.; Ash, R.D.; Li, X.; Zhou, J.; Mullins, C.B.

    2016-01-01

    We report the synthesis of silicon-doped hematite (Si:alpha-Fe2O3) single crystals via chemical vapor transport, with Si incorporation on the order of 1019 cm(-3). The conductivity, Seebeck and Hall effect were measured in the basal plane between 200 and 400 K. Distinct differences in electron

  15. Hierarchical zeolites: progress on synthesis and characterization of mesoporous zeolite single crystal catalysts

    DEFF Research Database (Denmark)

    Kustova, Marina; Egeblad, Kresten; Christensen, Claus H.

    2007-01-01

    Recently, a new family of crystalline zeolitic materials was reported, the so-called mesoporous zeolite single crystals featuring individual zeolite single crystals with an additional noncrystalline mesopore system interconnected with the usual micropore system of the zeolite, resulting...... measurements. Additionally, the results of diffusion of n-hexadecane in conventional and mesoporous zeolites are presented. Isomerization and cracking of n-hexadecane was chosen as model test reaction for these materials. All results support that mesoporous zeolites are superior catalysts due to improved mass...... transport. Importantly, the mesoporous zeolites show significant improved resistance to poisoning by carbon formation....

  16. Soft chemistry routes to transparent metal oxide thin films. The case of sol–gel synthesis and structural characterization of Ta{sub 2}O{sub 5} thin films from tantalum chloromethoxide

    Energy Technology Data Exchange (ETDEWEB)

    Epifani, Mauro, E-mail: mauro.epifani@le.imm.cnr.it [Istituto per la Microelettronica e i Microsistemi, IMM-CNR, Via Monteroni, 73100 Lecce (Italy); Zamani, Reza [Catalonia Institute for Energy Research, IREC c/Jardins de les Dones de Negre, 1, 08930-Sant Adria del Besos, Barcelona (Spain); Institut de Ciència de Materials de Barcelona, ICMAB-CSIC, 08193 Bellaterra, CAT (Spain); Arbiol, Jordi [Institut de Ciència de Materials de Barcelona, ICMAB-CSIC, 08193 Bellaterra, CAT (Spain); Institucio Catalana de Recerca i Estudis Avançats, ICREA, 08010, Barcelona (Spain); Fabrega, Cristian; Andreu, Teresa [Catalonia Institute for Energy Research, IREC c/Jardins de les Dones de Negre, 1, 08930-Sant Adria del Besos, Barcelona (Spain); Pace, Giovanni Battista; Siciliano, Pietro [Istituto per la Microelettronica e i Microsistemi, IMM-CNR, Via Monteroni, 73100 Lecce (Italy); Morante, Joan R. [Catalonia Institute for Energy Research, IREC c/Jardins de les Dones de Negre, 1, 08930-Sant Adria del Besos, Barcelona (Spain); M2E-IN2UB-XaRMAE, Departament d’Electrònica, Universitat de Barcelona, C. Martí i Franquès 1, 08028 Barcelona, CAT (Spain)

    2014-03-31

    Ta{sub 2}O{sub 5} thin films were prepared by spin-coating methanol solutions of Ta chloromethoxide. It was prepared by reacting TaCl{sub 5} with methanol, followed by water addition (H{sub 2}O: Ta molar ratio was 16). Thin films were deposited by spin-coating onto SiO{sub 2}/Si substrates, followed by drying at 90 °C and heat-treatment up to 700 °C. The films were characterized by X-ray diffraction, transmission electron microscopy and field emission scanning electron microscopy. Crystallization was obtained only after heating at 700 °C, in the Ta{sub 2}O{sub 5} orthorhombic phase. The resulting films had a thickness of 100 nm. Their structure was constituted by porous crystals with size up to 50 nm, while the pores had a size of about 10 nm. The results demonstrated that TaCl{sub 5} is very convenient precursor for the wet chemical synthesis of Ta{sub 2}O{sub 5} thin films. - Highlights: • Development of convenient solution synthesis of Ta{sub 2}O{sub 5} thin films; • The precursor chemistry was established and related to the synthesis process; • Uniform films crystallized in the most stable orthorombic Ta{sub 2}O{sub 5} phase;.

  17. Synthesis, characterization and electro-optic properties of novel siloxane liquid crystalline with a large tilt angle

    International Nuclear Information System (INIS)

    Liao, Chien-Tung; Lee, Jiunn-Yih; Lai, Chiu-Chun

    2011-01-01

    Research highlights: → In this study we report the synthesis and characterization of new ferroelectric liquid crystal material. → We examined the influence of the addition of a trisiloxane end-group on one side-chain of an achiral alkyl chain on the phase transition. → Finally, the properties of the chiral smectic C (SmC*) phase were measured for target compounds. - Abstract: This paper presents a study of the ferroelectric behavior in low molar mass organosiloxane liquid crystal materials. A few novel series of compounds with a large tilt angle were synthesized, and the mesophases exhibited were compared. The mesophases under discussion were investigated by means of polarizing microscopy (POM), differential scanning calorimetry (DSC), X-ray diffraction (XRD) and electro-optical experiments. The influence of the molecular structure on the occurrence of the chiral smectic C (SmC*) phase was investigated. Finally, the electro-optical properties of the SmC* phase, such as tilt angle, dielectric permittivity and switching behavior were also measured. As a consequence, the correlation between the electro-optical properties and chemical structures of these compounds was investigated.

  18. Structural and functional characterization of HPHT diamond crystals used in photoconductive devices

    Energy Technology Data Exchange (ETDEWEB)

    Pace, E.; Pini, A. [Florence Univ. (Italy). Ist. di Astronomia; Vinattieri, A.; Bogani, F.; Santoro, M.; Messina, G.; Santangelo, S.; Sato, Y.

    2000-09-01

    Diamond films are extensively studied for applications as functional material for UV photoconductors. CVD-grown polycrystalline diamond films show very interesting performances, but their complete exploitation is actually limited by a slow time response if compared to other materials, by a relatively high concentration of structural defects, impurities and grain boundaries, which may affect the collection length of photogenerated charges. High-quality single crystal diamonds could solve some of these problems. The absence of grain boundaries can produce longer collection lengths. The nitrogen and impurity contents can be reduced and then large type-IIa diamond single-crystals can be obtained. In this work, a detailed structural and functional characterization of type Ib HPHT diamond crystals has been carried out and the results have been compared to similar characterizations of CVD films to evaluate the different behavior, taking also into account that these high pressure high temperature (HPHT) diamond crystals contain several tens ppm of nitrogen. (orig.)

  19. Mononuclear mercury(II) complexes containing bipyridine derivatives and thiocyanate ligands: Synthesis, characterization, crystal structure determination, and luminescent properties

    Science.gov (United States)

    Amani, Vahid; Alizadeh, Robabeh; Alavije, Hanieh Soleimani; Heydari, Samira Fadaei; Abafat, Marzieh

    2017-08-01

    A series of mercury(II) complexes, [Hg(Nsbnd N)(SCN)2] (Nsbnd N is 4,4‧-dimethyl-2,2‧-bipyridine in 1, 5,5‧-dimethyl-2,2‧-bipyridine in 2, 6,6‧-dimethyl-2,2‧-bipyridine in 3 and 6-methyl-2,2‧-bipyridine in 4), were prepared from the reactions of Hg(SCN)2 with mentioned ligands in methanol. Suitable crystals of these complexes were obtained for X-ray diffraction measurement by methanol diffusion into a DMSO solution. The four complexes were thoroughly characterized by spectral methods (IR, UV-Vis, 13C{1H}NMR, 1H NMR and luminescence), elemental analysis (CHNS) and single crystal X-ray diffraction. The X-ray structural analysis indicated that in the structures of these complexes, the mercury(II) cation is four-coordinated in a distorted tetrahedral configuration by two S atoms from two thiocyanate anions and two N atoms from one chelating 2,2‧-bipyridine derivative ligand. Also, in these complexes intermolecular interactions, for example Csbnd H⋯N hydrogen bonds (in 1-4), Csbnd H⋯S hydrogen bonds (in 1, 2 and 4), π … π interactions (in 2-4), Hg⋯N interactions (in 2) and S⋯S interactions (in 4), are effective in the stabilization of the crystal structures and the formation of the 3D supramolecular complexes. Furthermore, the luminescence spectra of the title complexes show that the intensity of their emission bands are stronger than the emission bands for the free bipyridine derivative ligands.

  20. Niobium-Doped Hydroxyapatite Bioceramics: Synthesis, Characterization and In Vitro Cytocompatibility

    Directory of Open Access Journals (Sweden)

    Nádia S. V. Capanema

    2015-07-01

    Full Text Available Doping calcium phosphates with ionic species can play an important role in biological responses promoting alkaline phosphatase activity, and, therefore inducing the generation of new bone. Thus, in this study, the synthesis of niobium-doped hydroxyapatite (Nb-HA nanosize particles obtained by the precipitation process in aqueous media followed by thermal treatment is presented. The bioceramics were extensively characterized by X-ray diffraction, wavelength dispersive X-ray fluorescence spectrometry, Fourier transform infrared spectroscopy, scanning electron microscopy/energy dispersive X-ray spectroscopy analysis, transmission electron microscopy, atomic force microscopy and thermal analysis regarding their chemical composition, structure and morphology. The results showed that the precipitate dried at 110 °C was composed of amorphous calcium phosphate and HA, with polidisperse particles ranging from micro to nano dimensions. After the thermal treatment at 900 °C, the bioceramic system evolved predominantly to HA crystalline phase, with evident features of particle sintering and reduction of surface area. Moreover, the addition of 10 mol% of niobium salt precursor during the synthesis indicated the complete incorporation of the Nb(V species in the HA crystals with detectable changes in the original lattice parameters. Furthermore, the incorporation of Nb ions caused a significant refinement on the average particle size of HA. Finally, the preliminary cytocompatibility response of the biomaterials was accessed by human osteoblast cell culture using MTT and resazurin assays, which demonstrated no cytotoxicity of the Nb-alloyed hydroxyapatite. Thus, these findings seem promising for developing innovative Nb-doped calcium phosphates as artificial biomaterials for potential use in bone replacements and repair.

  1. Synthesis and Characterization of Zeolite Na−Y and Its Conversion to the Solid Acid Zeolite H−Y

    DEFF Research Database (Denmark)

    Warner, Terence Edwin; Galsgaard Klokker, Mads; Nielsen, Ulla Gro

    2017-01-01

    Zeolite Y has an iconic crystal structure, but more importantly, the hydrogen modification zeolite H−Y is the classic example of a solid acid which is used extensively as a catalyst in the oil industry. This metastable compound cannot be synthesized directly, which creates an opportunity to discuss...... various preparative strategies with the students, such as the three-stage procedure described here. Stage I concerns the hydrothermal synthesis of zeolite Na−Y, followed by ion-exchange with an ammonium acetate solution to form zeolite NH4−Y, and the latter is subsequently converted to zeolite H......−Y by thermolysis. Stages II and III may instead be performed using commercially available zeolites, Na−Y and NH4−Y, respectively, which shifts the learning objectives to structural characterization of zeolites. The characterization of the product and intermediate materials gives the students a practical insight...

  2. Synthesis of liquid crystals derived from nitroazobenzene: a proposed multistep synthesis applied to organic chemistry laboratory classes

    International Nuclear Information System (INIS)

    Cristiano, Rodrigo; Cabral, Marilia Gabriela B.; Aquino, Rafael B. de; Cristiano, Claudia M.Z.

    2014-01-01

    We describe a synthetic route consisting of five steps from aniline to obtain liquid crystal compounds derived from nitroazobenzene. Syntheses were performed during the second half of the semester in organic chemistry laboratory classes. Students characterized the liquid crystal phase by the standard melting point techniques, differential scanning calorimetry and polarized optical microscopy. These experiments allow undergraduate students to explore fundamentally important reactions in Organic Chemistry, as well as modern concepts in Chemistry such as self-assembly and self-organization, nanostructured materials and molecular electronics. (author)

  3. Fixation of CO2 in air: Synthesis and crystal structure of a µ3-CO3 ...

    Indian Academy of Sciences (India)

    Unknown

    Fixation of CO2 in air: Synthesis and crystal structure of a ... from the reaction between copper(I) complexes and dioxygen.2,6,7 ... and co-workers from the reaction of [(L2) ..... followed by water dissociation.13h,24 While fixation of CO2 by ...

  4. Synthesis, characterization and behaviour of trans-bis (argininate) copper (II) to gamma radiation

    International Nuclear Information System (INIS)

    Pereira, A.B.

    1984-01-01

    The synthesis, the characterization and the behaviour to gamma radiation of trans-bis (argininate) copper (II) are presented. The synthesis is made from copper sulfate, sodium hydroxide and hydrochloride of L (+) arginine, in aqueous medium, and the characterization by infrared spectroscopy, visible and ultraviolet spectroscopy and elementary analysis. (C.G.C.)

  5. Synthesis and characterization of organically linked ZnO nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Chory, Christine; Riedel, Ingo; Parisi, Juergen [Energy and Semiconductor Research Laboratory (EHF), University of Oldenburg, Carl-von Ossietzky-Strasse 9-11, 26129 Oldenburg (Germany); Kruska, Carsten; Heimbrodt, Wolfram [Department of Physics and Material Sciences Center, Philipps-University Marburg, Renthof 5, 35032 Marburg (Germany); Feser, Clemens [NEXT ENERGY - EWE Research Centre for Energy Technology e.V., Carl-von Ossietzky-Strasse 15, 26129 Oldenburg (Germany); Beenken, Wichard J.D. [Department of Theoretical Physics I, Ilmenau University of Technology, Weimarer Strasse 25, 98693 Ilmenau (Germany); Hoppe, Harald [Department of Experimental Physics I, Ilmenau University of Technology, Weimarer Strasse 32, 98693 Ilmenau (Germany)

    2012-11-15

    We report on the solution-based synthesis and characterization of three-dimensional networks of ZnO nanoparticles where the formation of structures is achieved by covalently linking the nanocrystals with bifunctional organic ligands. The colloidal synthesis will be presented with application of two ligands that vary in size and binding sites. Furthermore we report on structural characterization of dried powders and thin films by means of X-ray diffraction and electron microscopy in order to examine the regularity of the structures. We also present first investigations of the optical properties and electrical conductance behavior in lateral direction of the differently linked hybrid ZnO networks. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  6. Synthesis and characterization of organically linked ZnO nanoparticles

    International Nuclear Information System (INIS)

    Chory, Christine; Riedel, Ingo; Parisi, Juergen; Kruska, Carsten; Heimbrodt, Wolfram; Feser, Clemens; Beenken, Wichard J.D.; Hoppe, Harald

    2012-01-01

    We report on the solution-based synthesis and characterization of three-dimensional networks of ZnO nanoparticles where the formation of structures is achieved by covalently linking the nanocrystals with bifunctional organic ligands. The colloidal synthesis will be presented with application of two ligands that vary in size and binding sites. Furthermore we report on structural characterization of dried powders and thin films by means of X-ray diffraction and electron microscopy in order to examine the regularity of the structures. We also present first investigations of the optical properties and electrical conductance behavior in lateral direction of the differently linked hybrid ZnO networks. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  7. Development and characterization of Mn{sup 2+}-doped MgO nanoparticles by solution combustion synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Basha, Md. Hussain; Gopal, N. O., E-mail: nogopal@yahoo.com [Department of Physics, Vikrama Simhapuri University Post Graduate Center, Kavali-524201 (India); Rao, J. L. [Department of physics, Sri Venkateswara University, Tirupati-517502 (India); Nagabhushana, H. [Prof. C.N.R. Rao Centre for Nano Research, Tumkur University, Tumkur-572103 (India); Nagabhushana, B. M. [Department of Chemistry, M.S. Ramaiah Institute of Technology, Bangalore - 560054 (India); Chakradhar, R. P. S. [CSIR- National Aerospace Laboratories, Bangalore -560017 (India)

    2015-06-24

    Mn doped MgO Nanoparticles have been prepared by Solution Combustion Synthesis. The synthesized sample is characterized by X-ray diffraction (XRD), Scanning Electron Microscopy (SEM) and Electron Paramagnetic Resonance (EPR). The prepared MgO:Mn (1 mol%) nano crystals appear to be of simple cubic crystalline phase with lattice parameters a = 4.218(2) Å and cell volume = 74.98 (7) Å{sup 3}. SEM micrograph of powders show highly porous, many agglomerates with irregular morphology, large voids, cracks and pores. EPR spectrum of the sample at room temperature exhibit an isotropic sextet hyperfine pattern, centered at g=1.99, characteristic if Mn{sup 2+} ions with S=I=5/2.The observed g value and the hyperfine value reveal the ionic bonding between Mn{sup 2+} and its surroundings.

  8. Synthesis, Crystal Structure, and DFT Calculations of 1,3-Diisobutyl Thiourea

    Directory of Open Access Journals (Sweden)

    Ataf A. Altaf

    2015-01-01

    Full Text Available 1,3-Diisobutyl thiourea was synthesized and characterized by single crystal X-ray diffraction. It gives a monoclinic (α = γ = 90 and β  ≠ 90 structure with the space group P21/c. The unit cell dimensions are a = 11.5131 (4 Å, b = 9.2355 (3 Å, c = 11.3093 (5 Å, α = 90°, β = 99.569° (2, γ = 90°, V = 1185.78 (8 Å3, and Z = 4. The crystal packing is stabilized by intermolecular (N–H⋯S hydrogen bonding in the molecules. The optimized geometry and Mullikan's charges of the said molecule calculated with the help of DFT using B3LYP-6-311G model support the crystal structure.

  9. Anatase TiO2 single crystals with dominant {0 0 1} facets: Synthesis, shape-control mechanism and photocatalytic activity

    Science.gov (United States)

    Tong, Huifen; Zhou, Yingying; Chang, Gang; Li, Pai; Zhu, Ruizhi; He, Yunbin

    2018-06-01

    Anatase TiO2 micro-crystals with 51% surface exposing highly active {0 0 1} facets are prepared by hydrothermal synthesis using TiF4 as Ti resource and HF as morphology control agent. In addition, anatase TiO2 single crystals exposing large {0 0 1} crystal facets are facilely synthesized with "green" NaF plus HCl replacing HF for the morphology control. A series of comparative experiments are carried out for separately studying the effects of F- and H+ concentrations on the growth of TiO2 crystals, which have not been understood very much in depth so far. The results indicate that both F- and H+ synergistically affect the synthesis of truncated anatase octahedrons, where F- is preferentially adsorbed on the {0 0 1} facets resulting in lateral growth of these facets and H+ adjusts the growth rate of anatase TiO2 along different orientations by tuning the hydrolysis rate. Based on this information, anatase TiO2 single crystals with small size (1.3 μm) and large exposure of {0 0 1} facets (45%) are successfully prepared under optimal conditions ([H+]/[F-] = 20:1). Photocatalytic activities of the as-prepared products toward methylene blue photo-degradation are further tested. It is revealed that both crystal size and percentage of {0 0 1} facets are decisive for the photocatalytic performance, and the crystals with a small size (1.3 μm) and large exposure of {0 0 1} facets (45%) are catalytically most active. This work has clarified the main factors that control the growth process and morphology of anatase TiO2 single crystals for achieving superior photocatalytic properties.

  10. Generation of mariner-based transposon insertion mutant library of Bacillus sphaericus 2297 and investigation of genes involved in sporulation and mosquito-larvicidal crystal protein synthesis.

    Science.gov (United States)

    Wu, Yiming; Hu, Xiaomin; Ge, Yong; Zheng, Dasheng; Yuan, Zhiming

    2012-05-01

    Bacillus sphaericus has been used with great success in mosquito control programs worldwide. Under conditions of nutrient limitation, it undergoes sporulation via a series of well defined morphological stages. However, only a small number of genes involved in sporulation have been identified. To identify genes associated with sporulation, and to understand the relationship between sporulation and crystal protein synthesis, a random mariner-based transposon insertion mutant library of B. sphaericus strain 2297 was constructed and seven sporulation-defective mutants were selected. Sequencing of the DNA flanking of the transposon insertion identified several genes involved in sporulation. The morphologies of mutants were determined by electron microscopy and synthesis of crystal proteins was analyzed by SDS-PAGE and Western blot. Four mutants blocked at early stages of sporulation failed to produce crystal proteins and had lower larvicidal activity. However, the other three mutants were blocked at later stages and were able to form crystal proteins, and the larvicidal activity was similar to wild type. These results indicated that crystal protein synthesis in B. sphaericus is dependent on sporulation initiation. © 2012 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

  11. Synthesis, characterization, crystal structures, QSAR study and antibacterial activities of organotin bisphosphoramidates

    Czech Academy of Sciences Publication Activity Database

    Gholivand, K.; Valmoozi, A.A.E.; Gholami, A.; Dušek, Michal; Eigner, Václav; Abolghasemi, S.

    2016-01-01

    Roč. 806, Mar (2016), s. 33-44 ISSN 0022-328X R&D Projects: GA ČR GA15-12653S Institutional support: RVO:68378271 Keywords : bisphosphoramidate * organotin compounds * crystal structure * antibacterial activity * QSAR Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 2.184, year: 2016

  12. Synthesis and characterization of transition-metal-doped zinc oxide nanocrystals for spintronics

    Science.gov (United States)

    Wang, Xuefeng

    Spintronics (spin transport electr onics), in which both spin and charge of carriers are utilized for information processing, is believed to challenge the current microelectronics and to become the next-generation electronics. Nanostructured spintronic materials and their synthetic methodologies are of paramount importance for manufacturing future nanoscale spintronic devices. This thesis aims at studying synthesis, characterization, and magnetism of transition-metal-doped zinc oxide (ZnO) nanocrystals---a diluted magnetic semiconductor (DMS)---for potential applications in future nano-spintronics. A simple bottom-up-based synthetic strategy named a solvothermal technique is introduced as the primary synthetic approach and its crystal growth mechanism is scrutinized. N-type cobalt-doped ZnO-based DMS nanocrystals are employed as a model system, and characterized by a broad spectrum of advanced microscopic and spectroscopic techniques. It is found that the self-orientation growth mechanism, imperfect oriented attachment, is intimately correlated with the high-temperature ferromagnetism via defects. The influence of processing on the magnetic properties, such as compositional variations, reaction conditions, and post-growth treatment, is also studied. In this way, an in-depth understanding of processing-structure-property interrelationships and origins of magnetism in DMS nanocrystals are obtained in light of the theoretical framework of a spin-split impurity band model. In addition, a nanoscale spinodal decomposition phase model is also briefly discussed. Following the similar synthetic route, copper- and manganese-doped ZnO nanocrystals have been synthesized and characterized. They both show high-temperature ferromagnetism in line with the aforementioned theoretical model(s). Moreover, they display interesting exchange biasing phenomena at low temperatures, revealing the complexity of magnetic phases therein. The crystal growth strategy demonstrated in this work

  13. Hydrothermal synthesis, characterization, and thermal properties of alumino silicate azide sodalite, Na8[AlSiO4]6(N3)2

    Science.gov (United States)

    Borhade, A. V.; Wakchaure, S. G.; Dholi, A. G.; Kshirsagar, T. A.

    2017-07-01

    First time we report the synthesis, structural characterization and thermal behavior of an unusual N3 - containing alumino-silicate sodalite mineral. Azide sodalite, Na8[AlSiO4]6(N3)2 has been synthesized under hydrothermal conditions at 433 K in steel lined Teflon autoclave. The structural and microstructural properties of azide sodalite mineral was characterized by various methods including FT-IR, XRD, SEM, TGA, and MAS NMR. Crystal structure have been refined by Rietveld method in P\\bar 43n space group, indicating that the N3 - sodalite has cubic in lattice. High temperature study was carried out to see the effect of thermal expansion on cell dimension ( a o) of azide sodalite. Thermal behavior of sodalite was also assessed by thermogravimetric method.

  14. Synthesis and characterization of germa[n]pericyclynes.

    Science.gov (United States)

    Tanimoto, Hiroki; Nagao, Tomohiko; Nishiyama, Yasuhiro; Morimoto, Tsumoru; Iseda, Fumiyasu; Nagato, Yuko; Suzuka, Toshimasa; Tsutsumi, Ken; Kakiuchi, Kiyomi

    2014-06-14

    The synthesis and characterization of novel pericyclynes comprising germanium atoms and acetylenes, germa[n]pericyclynes, are described. The prepared germa[4]-, [6]-, and [8]pericyclynes were compared by (13)C NMR spectroscopy, X-ray crystallography, cyclic voltammetry, UV-visible spectroscopy, fluorescence emission spectroscopy, Raman spectroscopy, and density functional theory calculation analyses.

  15. Mesoporous CdS via Network of Self-Assembled Nanocrystals: Synthesis, Characterization and Enhanced Photoconducting Property.

    Science.gov (United States)

    Patra, Astam K; Banerjee, Biplab; Bhaumik, Asim

    2018-01-01

    Semiconduction nanoparticles are intensively studied due to their huge potential in optoelctronic applications. Here we report an efficient chemical route for hydrothermal synthesis of aggregated mesoporous cadmium sulfide (CdS) nanoparticles using supramolecular-assembly of ionic and water soluble sodium salicylate as the capping agent. The nanostructure, mesophase, optical property and photoconductivity of these mesoporous CdS materials have been characterized by using small and wide angle powder X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), N2-sorption, Raman analysis, Fourier transformed infrared (FT-IR), UV-Visible DSR spectroscopy, and photoconductivity measurement. Wide angle XRD pattern and high resolution TEM image analysis suggested that the particle size of the materials is within 10 nm and the nanoparticles are in well-crystallized cubic phase. Mesoporous CdS nanoparticles showed drastically enhanced photoelectrochemical response under visible light irradiation on entrapping a photosensitizer (dye) molecule in the interparticle spaces. Efficient synthesis strategy and the enhanced photo response in the mesoporous CdS material could facilitate the designing of other porous semiconductor oxide/sulfide and their applications in photon-to-electron conversion processes.

  16. Synthesis of novel liquid crystal compounds and their blood compatibility as anticoagulative materials

    International Nuclear Information System (INIS)

    Tu Mei; Cha Zhenhang; Feng Bohua; Zhou Changren

    2006-01-01

    The objective of this study was to synthesize new types of cholesteric liquid crystal compounds and study the anticoagulative properties of their composite membranes. Three kinds of cholesteric liquid crystal compounds were synthesized and characterized by infrared spectroscopy, differential scanning calorimetry and optical polarizing microscope. The polysiloxane, as a substrate, was blended with three liquid crystal compounds and was then used as membranes. The anticoagulative property of different polysiloxane liquid crystal composite membranes was identified by the blood compatibility tests. Three cholesteryl liquid crystals synthesized in this work contained hydrophilic soft chains and presented iridescent texture owned by cholesteric liquid crystals in the range of their liquid crystal state temperature, but only cholesteryl acryloyl oxytetraethylene glycol carbonate was in the liquid crystal state at body temperature. When liquid crystals were blended with polysiloxane to form polysiloxane/liquid crystal composite membranes, the haemocompatibility of these membranes could be improved to some extent. The blood compatibility of composite membranes whose hydrophilic property was the best was more excellent than that of other composite membranes, fewer platelets adhered and spread, and showed little distortion on the surface of materials

  17. Crystal chemical characterization of mullite-type aluminum borate compounds

    Energy Technology Data Exchange (ETDEWEB)

    Hoffmann, K., E-mail: Kristin.Hoffmann@uni-bremen.de [Kristallographie, FB05, Klagenfurter Straße / GEO, Universität Bremen, D-28359 Bremen (Germany); Institut für Anorganische Chemie und Kristallographie, FB02, Leobener Straße / NW2, Universität Bremen, D-28359 Bremen (Germany); Hooper, T.J.N. [Department of Physics, University of Warwick, Coventry CV4 7AL (United Kingdom); Zhao, H.; Kolb, U. [Institut für Anorganische Chemie und Analytische Chemie, Jakob-Welder-WegJakob-Welder-Weg 11, Johannes Gutenberg-University Mainz, D-55128 Mainz (Germany); Murshed, M.M. [Institut für Anorganische Chemie und Kristallographie, FB02, Leobener Straße / NW2, Universität Bremen, D-28359 Bremen (Germany); MAPEX Center for Materials and Processes, Bibliothekstraße 1, Universität Bremen, D-28359 Bremen (Germany); Fischer, M.; Lührs, H. [Kristallographie, FB05, Klagenfurter Straße / GEO, Universität Bremen, D-28359 Bremen (Germany); MAPEX Center for Materials and Processes, Bibliothekstraße 1, Universität Bremen, D-28359 Bremen (Germany); Nénert, G. [Institut Laue-Langevin, 6 Rue Jules Horowitz, 38042 Grenoble Cedex 9 (France); Kudějová, P.; Senyshyn, A. [Heinz Maier-Leibnitz Zentrum (MLZ), Technische Universität München, Lichtenbergstr. 1, D-85748 Garching (Germany); and others

    2017-03-15

    Al-rich aluminum borates were prepared by different synthesis routes using various Al/B ratios, characterized by diffraction methods, spectroscopy and prompt gamma activation analysis. The {sup 11}B NMR data show a small amount of BO{sub 4} species in all samples. The chemical analysis indicates a trend in the Al/B ratio instead of a fixed composition. Both methods indicate a solid solution Al{sub 5−x}B{sub 1+x}O{sub 9} where Al is substituted by B in the range of 1–3%. The structure of B-rich Al{sub 4}B{sub 2}O{sub 9} (C2/m, a=1488 pm, b=553 pm, c=1502 pm, ß=90.6°), was re-investigated by electron diffraction methods, showing that structural details vary within a crystallite. In most of the domains the atoms are orderly distributed, showing no signal for the postulated channel oxygen atom O5. The absence of O5 is supported by density functional theory calculations. Other domains show a probable disordered configuration of O5 and O10, indicated by diffuse scattering along the b direction. - Graphical abstract: Projections of three-dimensional electron diffraction space of Al{sub 4}B{sub 2}O{sub 9} along the main directions. - Highlights: • The crystal structure of Al{sub 4}B{sub 2}O{sub 9} was re-evaluated. • Structural details vary among different crystals and inside Al{sub 4}B{sub 2}O{sub 9} crystallites. • Diffuse scattering indicate a probable disordered configuration of O5 and O10. • A solid solution series for Al{sub 5−x}B{sub x}O{sub 9} is indicated by PGAA and NMR spectroscopy. • The presence of BO{sub 4} groups is confirmed by {sup 11}B MAS NMR spectroscopy for Al{sub 5−x}B{sub 1+x}O{sub 9}.

  18. Crystal chemistry, properties and synthesis of microporous silicates containing transition elements

    International Nuclear Information System (INIS)

    Chukanov, Nikita V; Pekov, Igor V; Rastsvetaeva, Ramiza K

    2004-01-01

    The review surveys and generalises recent data on synthesis methods, physicochemical properties and crystal chemistry of silicate microporous materials containing transition elements (amphoterosilicates). The frameworks of these materials, unlike those of usual aluminosilicate zeolites, are built from tetrahedrally coordinated atoms along with atoms of various elements (Ti, Nb, Zr, Ta, Sn, W, Fe, Mn, Zn, etc.) with coordination numbers of 6 or 5. Many amphoterosilicates possess ion-exchange properties and can serve as catalysts for redox reactions, sorbents, etc. The structural diversity of synthetic and natural amphoterosilicates provides the basis for the preparation of microporous materials with different properties.

  19. Synthesis, crystal structure and characterization of a 1D polyoxometalate-based compound: {l_brace}[Pr(H{sub 2}O){sub 7}][CrMo{sub 6}H{sub 6}O{sub 24}]{r_brace} . 4H{sub 2}O

    Energy Technology Data Exchange (ETDEWEB)

    Zhao Lijie; Shen Shuchang; Yu Haiming [Qiqihar Univ., HL (China). Dept. of Chemistry and Chemical Engineering

    2008-07-15

    A novel polyoxometalated-based compound, {l_brace}[Pr(H{sub 2}O){sub 7}][CrMo{sub 6}H{sub 6}O{sub 24}]{r_brace} . 4H{sub 2}O, was prepared and characterized by elemental analysis, infrared and ultraviolet spectroscopy, TG measurement and single crystal X-ray diffraction. A chain-like coordination polymer is formed from a heteropolyanion [CrMo{sub 6}H{sub 6}O{sub 24}]{sup 3} as a building unit and [Pr(H{sub 2}O){sub 7}]{sup 3+} cations as linker. The chains are linked into an extensive three-dimensional supramolecular network through hydrogen bonding. The synthesis of 1 is accomplished only from pre-synthesized Anderson clusters, but not from simple starting materials. (orig.)

  20. Synthesis & Characterization of New bis-Symmetrical Adipoyl ...

    African Journals Online (AJOL)

    Full Title: Synthesis and Characterization of New bis-Symmetrical Adipoyl, Terepthaloyl, Chiral Diimido-di-L-alanine Diesters and Chiral Phthaloyl-L-alanine Ester of Tripropoxy p-tert-Butyl Calix[4]arene and Study of Their Hosting Ability for Alanine and Na+. Bis-symmetrical tripropoxy p-tert-butyl calix[4]arene esters were ...

  1. Influence of crystallization time on structural and morphological characteristics the precursor of zeolite MCM-22

    International Nuclear Information System (INIS)

    Barbosa, A.S.; Lima, L.A.; Sousa, B.V.; Santos, Everton R.F. dos; Rodrigues, M.G.F.

    2009-01-01

    The zeolite MCM-22 has been studied extensively as a promising catalyst because of the high thermal stability and high activity for acid catalysis and selectivity of molecular shape. The synthesis of MCM-22 is carried out by hydrothermal treatment and long times required for complete crystallization gradual growth of crystals of 10-14 days for the synthesis of static. This work aims to synthesize the precursor of zeolite MCM-22 using the method of hydrothermal synthesis with a reduction in crystallization time of 8 and 9 days. The precursor of zeolite MCM-22 was obtained using sources of silica, soda, deionized water and the director of structures hexametilenoimina (HMI). The samples were synthesized at 150° C for 8 to 9 days, with the following molar composition: 0.511 SiO 2 : 0.039 NaOH: 0.024 Al 2 O 3 : 23.06 H 2 O and subjected to characterizations by X-ray diffraction (XRD), scanning electron microscopy ( SEM) and energy dispersive (EDX). According to tests carried out showed that the hydrothermal treatment used to synthesize the precursor of zeolite MCM-22 was effective during times of crystallization of 8 and 9 days. The results for the micrographs showed that the samples consist of clusters and / or aggregates of small crystals. (author)

  2. Synthesis and structural characterization of a calcium coordination ...

    Indian Academy of Sciences (India)

    Synthesis and structural characterization of a calcium coordination polymer based on a μ3-bridging. tetradentate binding mode of glycine. SUBRAMANIAN NATARAJAN*a, BIKSHANDARKOIL R. SRINIVASANb , J. KALYANA SUNDARa, K. RAVIKUMARc , R.V. KRISHNAKUMARd , J. SURESHe,. aSchool of Physics, ...

  3. Synthesis, characterization and structural refinement of polycrystalline uranium substituted zirconolite

    International Nuclear Information System (INIS)

    Shrivastava, O.P.; Narendra Kumar; Sharma, I.B.

    2005-01-01

    Ceramic precursors of Zirconolite (CaZrTi 2 O 7 ) family have a remarkable property of substitution Zr 4+ cationic sites. This makes them potential material for nuclear waste management in 'synroc' technology. In order to simulate the mechanism of partial substitution of zirconium by tetravalent actinides, a solid phase of composition CaZr 0.95 U 0.5 Ti 2 O 7 has been synthesized through ceramic route by taking calculated quantities of oxides of Ca, Ti and nitrates of uranium and zirconium respectively. Solid state synthesis has been carried out by repeated pelletizing and sintering the finely powdered oxide mixture in a muffle furnace at 1050 degC. The polycrystalline solid phase has been characterized by its typical powder diffraction pattern. Step analysis data has been used for ab initio calculation of structural parameters. The uranium substituted zirconolite crystallizes in monoclinic symmetry with space group C2/c (15). The following unit cell parameters have been calculated: a =12.4883(15), b =7.2448(5), c 11.3973(10) and β = 100.615(9)0. The structure was refined to satisfactory completion. The Rp and Rwp are found to be 7.48% and 9.74% respectively. (author)

  4. Synthesis and characterization of graphene oxide using modified Hummer's method

    Science.gov (United States)

    Kaur, Manpreet; Kaur, Harsimran; Kukkar, Deepak

    2018-05-01

    In the present study, a simple approach has been followed for the synthesis of graphene oxide (GO) using modified Hummers method in which graphite powder was oxidized in the presence of concentrated H2SO4 and KMnO4. The amount of NaNO3 and KMnO4 was varied to produce sheet like structure. The varied concentrations of NaNO3 and KMnO4 resulted in yielding large amount of the product. Structural, morphological and physicochemical features of the product were studied using UV-Visible spectrophotometer, Fourier Transform infrared spectroscopy (FTIR), and crystal structure was determined using X-ray powder diffraction (XRD). UV-Vis spectra of GO was observed at a maximum absorption of 230 nm due to (π-π*) transition of atomic carbon-carbon bonds. FTIR spectra revealed the presence of oxygen containing functional groups which ensures the complete exfoliation of graphite into graphene oxide X-ray powder diffraction pattern of the product showed the diffraction peak at (2θ = 26.7°) with an interlayer spacing of 0.334 nm. All the above characterizations successfully confirmed the formation of GO.

  5. Magnetic zeolite NaA: synthesis, characterization based on metakaolin and its application for the removal of Cu2+, Pb2+.

    Science.gov (United States)

    Liu, Haibo; Peng, Shuchuan; Shu, Lin; Chen, Tianhu; Bao, Teng; Frost, Ray L

    2013-06-01

    The optimum parameters for synthesis of zeolite NaA based on metakaolin were investigated according to results of cation exchange capacity and static water adsorption of all synthesis products and selected X-ray diffraction (XRD). Magnetic zeolite NaA was synthesized by adding Fe3O4 in the precursor of zeolite. Zeolite NaA and magnetic zeolite NaA were characterized with scanning electron microscopy (SEM) and XRD. Magnetic zeolite NaA with different Fe3O4 loadings was prepared and used for removal of heavy metals (Cu(2+), Pb(2+)). The results show the optimum parameters for synthesis zeolite NaA are SiO2/Al2O3=2.3, Na2O/SiO2=1.4, H2O/Na2O=50, crystallization time 8h, crystallization temperature 95 °C. The addition of Fe3O4 makes the NaA zeolite with good magnetic susceptibility and good magnetic stability regardless of the Fe3O4 loading, confirming the considerable separation efficiency. Additionally, Fe3O4 loading had a little effect on removal of heavy metal by magnetic zeolite, however, the adsorption capacity still reaches 2.3 mmol g(-1) for Cu(2+), Pb(2+) with a removal efficiency of over 95% in spite of 4.7% Fe3O4 loading. This indicates magnetic zeolite can be used to remove metal heavy at least Cu(2+), Pb(2+) from water with metallic contaminants and can be separated easily after a magnetic process. Copyright © 2013 Elsevier Ltd. All rights reserved.

  6. Synthesis, characterization and crystal structures of new organic compounds containing cyanoacrylic acid

    Czech Academy of Sciences Publication Activity Database

    Khalaji, A.D.; Mogheiseh, M.; Eigner, Václav; Dušek, Michal; Chow, T.J.; Maddahi, E.

    2015-01-01

    Roč. 1098, Oct (2015), s. 318-323 ISSN 0022-2860 R&D Projects: GA ČR(CZ) GA14-03276S Institutional support: RVO:68378271 Keywords : organic compounds * cyanoacrylic acid * single-crystal structure analysis * dye-sensitized solar cells * density functional theory Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.780, year: 2015

  7. Synthesis and Characterization of Metal Phosphates for Photocatalytic Applications

    KAUST Repository

    Al-Sabban, Bedour

    2012-07-01

    Solar energy is the most abundant efficient and important source of renewable energy. The objective of this study is to develop highly efficient visible light responsive photocatalysts for overall water splitting. This is done by using silver or copper containing materials. Phosphate compounds have caught much attention due to their rigid structure, thermal stability and resistance to chemical attacks. Solid phosphates can be prepared by direct solid-state reaction between metal cations and phosphate anions at high temperatures. Double metal phosphates of the Nasion-type structure had shown further technological importance. It has been reported that well-crystallized double metal phosphate particles have excellent ordering and cationic conduction channels in the Nasicon framework. In this study, several Nasion-type structured materials have been synthesized by solid-state method (e.g. CuTi2(PO4)3 and AgTi2(PO4)3) heated up under different temperatures (400–1100C) in N2 or air atmosphere. These materials were characterized by XRD, SEM, DR-UV-Vis spectroscopy and tested for photocatalytic applications. A new method for direct synthesis of photoelectrode on Ti Plate had been demonstrated. Further investigations on controlling the size and morphology for better performance of single and double metal phosphates will be done.

  8. Polypyrrole-silver Nanocomposite: Synthesis and Characterization

    OpenAIRE

    D. M. Nerkar; S. V. Panse; S. P. Patil; S. E. Jaware; G. G. Padhye

    2016-01-01

    Polypyrrole-Silver (PPy-Ag) nanocomposite has been successfully synthesized by the chemical oxidative polymerization of pyrrole with iron (III) chloride as an oxidant, in the presence of a colloidal suspension of silver nanoparticles. Turkevich method (Citrate reduction method) was used for the synthesis of silver nanoparticles (Ag NPs). The silver nanoparticles were characterized by UV-Visible spectroscopy which showed an absorption band at 423 nm confirming the formation of nanoparticles. P...

  9. Growth and characterization of β-Ga2O3 crystals

    Science.gov (United States)

    Nikolaev, V. I.; Maslov, V.; Stepanov, S. I.; Pechnikov, A. I.; Krymov, V.; Nikitina, I. P.; Guzilova, L. I.; Bougrov, V. E.; Romanov, A. E.

    2017-01-01

    Here we report on the growth and characterization of β-Ga2O3 bulk crystals and polycrystalline layer on different substrates. Bulk β-Ga2O3 crystals were produced by free crystallisation of gallium oxide melt in sapphire crucible. Transparent single crystals measuring up to 8 mm across were obtained. Good structural quality was confirmed by x-ray diffraction rocking curve FWHM values of 46″. Young's modulus, shear modulus and hardness of the β-Ga2O3 crystals were measured by nanoindentation and Vickers microindentation techniques. Polycrystalline β-Ga2O3 films were deposited on silicon and sapphire substrates by sublimation method. It was found that structure and morphology of the films were greatly influenced by the material and orientation of the substrates. The best results were achieved on a-plane sapphire substrates where predominantly (111) oriented films were obtained.

  10. One dimensional coordination polymers: Synthesis, crystal structures and spectroscopic properties

    Science.gov (United States)

    Karaağaç, Dursun; Kürkçüoğlu, Güneş Süheyla; Şenyel, Mustafa; Şahin, Onur

    2016-11-01

    Two new one dimensional (1D) cyanide complexes, namely [M(4-aepy)2(H2O)2][Pt(CN)4], (4-aepy = 4-(2-aminoethyl)pyridine M = Cu(II) (1) or Zn(II) (2)), have been synthesized and characterized by vibrational (FT-IR and Raman) spectroscopy, single crystal X-ray diffraction, thermal and elemental analyses techniques. The crystallographic analyses reveal that 1 and 2 are isomorphous and isostructural, and crystallize in the monoclinic system and C2 space group. The Pt(II) ions are coordinated by four cyanide-carbon atoms in the square-planar geometry and the [Pt(CN)4]2- ions act as a counter ion. The M(II) ions display an N4O2 coordination sphere with a distorted octahedral geometry, the nitrogen donors belonging to four molecules of the organic 4-aepy that act as unidentate ligands and two oxygen atoms from aqua ligands. The crystal structures of 1 and 2 are similar each other and linked via intermolecular hydrogen bonding, Pt⋯π interactions to form 3D supramolecular network. Vibration assignments of all the observed bands are given and the spectral features also supported to the crystal structures of the complexes.

  11. Synthesis and crystal structure analysis of uranyl triple acetates

    Energy Technology Data Exchange (ETDEWEB)

    Klepov, Vladislav V., E-mail: vladislavklepov@gmail.com [Institute for Energy and Climate Research (IEK-6), Forschungszentrum Jülich GmbH, 52428 Jülich (Germany); Department of Chemistry, Samara National Research University, 443086 Samara (Russian Federation); Serezhkina, Larisa B.; Serezhkin, Victor N. [Department of Chemistry, Samara National Research University, 443086 Samara (Russian Federation); Alekseev, Evgeny V., E-mail: e.alekseev@fz-juelich.de [Institute for Energy and Climate Research (IEK-6), Forschungszentrum Jülich GmbH, 52428 Jülich (Germany); Institut für Kristallographie, RWTH Aachen University, 52066 Aachen (Germany)

    2016-12-15

    Single crystals of triple acetates NaR[UO{sub 2}(CH{sub 3}COO){sub 3}]{sub 3}·6H{sub 2}O (R=Mg, Co, Ni, Zn), well-known for their use as reagents for sodium determination, were grown from aqueous solutions and their structural and spectroscopic properties were studied. Crystal structures of the mentioned phases are based upon (Na[UO{sub 2}(CH{sub 3}COO){sub 3}]{sub 3}){sup 2–} clusters and [R(H{sub 2}O){sub 6}]{sup 2+} aqua-complexes. The cooling of a single crystal of NaMg[UO{sub 2}(CH{sub 3}COO){sub 3}]{sub 3}·6H{sub 2}O from 300 to 100 K leads to a phase transition from trigonal to monoclinic crystal system. Intermolecular interactions between the structural units and their mutual packing were studied and compared from the point of view of the stereoatomic model of crystal structures based on Voronoi-Dirichlet tessellation. Using this method we compared the crystal structures of the triple acetates with Na[UO{sub 2}(CH{sub 3}COO){sub 3}] and [R(H{sub 2}O){sub 6}][UO{sub 2}(CH{sub 3}COO){sub 3}]{sub 2} and proposed reasons of triple acetates stability. Infrared and Raman spectra were collected and their bands were assigned. - Graphical abstract: Single crystals of uranium based triple acetates, analytical reagents for sodium determination, were synthesized and structurally, spectroscopically and topologically characterized. The structures were compared with the structures of compounds from preceding families [M(H{sub 2}O){sub 6})][UO{sub 2}(CH{sub 3}COO){sub 3}]{sub 2} (M = Mg, Co, Ni, Zn) and Na[UO{sub 2}(CH{sub 3}COO){sub 3}]. Analysis was performed with the method of molecular Voronoi-Dirichlet polyhedra to reveal a large contribution of the hydrogen bonds into intermolecular interactions which can be a reason of low solubility of studied complexes.

  12. Synthesis and characterization of strontium carboxylates at room temperature and at high temperature in autoclave vessels

    DEFF Research Database (Denmark)

    Christgau, Stephan; Ståhl, Kenny; Andersen, Jens Enevold Thaulov

    2006-01-01

    A novel method was developed for synthesis of strontium coordination compounds in high yields. The synthesis proceeded along three pathways that provided strontium salts in high purity and high yields, close to 100%, as confirmed by flame atomic absorption spectroscopy (FAAS) and powder x......-ray crystallography. Optimum conditions were found at T = 120-1400C, a base-to-acid ratio of 1.2 and 15 min. of reaction-time in an autoclave vessel. Large crystals were readily obtained within a time period of hours. The crystal structures of strontium D-glutamate hexahydrate (I) and strontium di-(hydrogen L......-glutamate) pentahydrate (II) were confirmed by X-ray powder diffraction at 295 K and Rietveld refinements (I: Space group P212121, Z=4, a=7.3519(2), b=8.7616(2), c=20.2627(5) Å, and II: Space group P21, Z=2, a=8.7243(1), b=7.2635(1), c=14.6840(2) Å, β=100.5414(7) °). Synthesis at room temperature provided four additional...

  13. SYNTHESIS AND CHARACTERIZATION OF N, N'-BIS-(3 ...

    African Journals Online (AJOL)

    user

    base complexes derived from Salicylaldehyde and histidine with some divalent transition metal ions. Furthermore, Syed (1993) reported the synthesis, characterization and biological evaluation of some. Schiff base metal complexes derived from Anthranilic acid-sugar and naturally occurring amino acid-sugar. Schiff bases ...

  14. Fabrication and Characterization of Three Dimensional Photonic Crystals Generated by Multibeam Interference Lithography

    Science.gov (United States)

    Chen, Ying-Chieh

    2009-01-01

    Multibeam interference lithography is investigated as a manufacturing technique for three-dimensional photonic crystal templates. In this research, optimization of the optical setup and the photoresist initiation system leads to a significant improvement of the optical quality of the crystal, as characterized by normal incidence optical…

  15. Controllable synthesis of rice-shape Alq3 nanoparticles with single crystal structure

    Science.gov (United States)

    Xie, Wanfeng; Fan, Jihui; Song, Hui; Jiang, Feng; Yuan, Huimin; Wei, Zhixian; Ji, Ziwu; Pang, Zhiyong; Han, Shenghao

    2016-10-01

    We report the controllable growth of rice-shape nanoparticles of Alq3 by an extremely facile self-assembly approach. Possible mechanisms have been proposed to interpret the formation and controlled process of the single crystal nanoparticles. The field-emission performances (turn-on field 7 V μm-1, maximum current density 2.9 mA cm-2) indicate the potential application on miniaturized nano-optoelectronics devices of Alq3-based. This facile method can potentially be used for the controlled synthesis of other functional complexes and organic nanostructures.

  16. Synthesis and characterization of silver nanoparticles by sol-gel route from silver nitrate

    International Nuclear Information System (INIS)

    Morales, Jorge; Moran, Jose; Quintana, Maria; Estrada, Walter

    2009-01-01

    Silver nanoparticles colloids have been synthesized by sol-gel method. This synthesis consists in silver nitrate reduction by ethylene glycol in a process called polyol. The growth of the nanoparticles have been controlled by the steric stabilization of the colloid with polyvinylpyrrolidone (PVP, M w = 40 000). The silver nanoparticle size and structure was depending on the control of parameters such as: molar concentrations ratio of silver nitrate and PVP, temperature of reaction and the reflux time. Colloids have been characterized by UV-vis spectroscopy in the range from 300 to 1000 nm. The results show that the typical peak of surface plasmon resonance is formed at 400-450 nm indicating the formation of silver nanoparticles. The presences of silver nanoparticles of spherical shape with size among 20-40 nm were observed by transmission electronic microscopy (TEM). Electron diffraction patterns confirmed that synthesized colloids contain metallic silver with a crystal structure face centered cubic FCC. (author)

  17. Non-covalent interactions in 2-methylimidazolium copper(II) complex (MeImH)2[Cu(pfbz)4]: Synthesis, characterization, single crystal X-ray structure and packing analysis

    Science.gov (United States)

    Sharma, Raj Pal; Saini, Anju; Kumar, Santosh; Kumar, Jitendra; Sathishkumar, Ranganathan; Venugopalan, Paloth

    2017-01-01

    A new anionic copper(II) complex, (MeImH)2 [Cu(pfbz)4] (1) where, MeImH = 2-methylimidazolium and pfbz = pentafluorobenzoate has been isolated by reacting copper(II) sulfate pentahydrate, pentafluorobenzoic acid and 2-methylimidazole in ethanol: water mixture in 1:2:2 molar ratio. This complex 1 has been characterized by elemental analysis, thermogravimetric analysis, spectroscopic techniques (UV-Vis, FT-IR) and conductance measurements. The complex salt crystallizes in monoclinic crystal system with space group C2/c. Single crystal X-ray structure determination revealed the presence of discrete ions: [Cu(pfbz)4]2- anion and two 2-methylimidazolium cation (C4H7N2)+. The crystal lattice is stabilized by strong hydrogen bonding and F⋯F interactions between cationic-anionic and the anionic-anionic moieties respectively, besides π-π interactions.

  18. Two convenient low-temperature routes to single crystals of plutonium dioxide

    Energy Technology Data Exchange (ETDEWEB)

    Meredith, Nathan A. [Departments of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556 (United States); Wang, Shuao; Diwu, Juan [School of Radiation Medicine and Protection and School of Radiological and Interdisciplinary Sciences, Soochow University, Suzhou, Jiangsu 215123 (China); Albrecht-Schmitt, Thomas E., E-mail: talbrechtschmitt@gmail.com [Department of Chemistry and Biochemistry, Florida State University, Tallahassee, FL 32306 (United States)

    2014-11-15

    Highlights: • Two low-temperature routes to the growth single crystals of plutonium dioxide. • Safer methods of preparing PuO{sub 2} single crystals that do not involve solid-state synthetic techniques. • Solvothermal crystal growth of plutonium dioxide. - Abstract: During the solvothermal synthesis of a low-dimensional borate, KB{sub 5}O{sub 7}(OH){sub 2}⋅2H{sub 2}O, in the presence of Pu(III), single crystals of plutonium dioxide unexpectedly formed. Single crystals of PuO{sub 2} also formed during the hydrothermal synthesis of another borate, Na{sub 2}B{sub 5}O{sub 8}(OH)⋅2H{sub 2}O, in the presence of Pu(III). The reactions were conducted at 170 °C and 150 °C, respectively, which are much lower temperature than previously reported preparations of crystalline PuO{sub 2}. Yellow–green crystals with a tablet habit were characterized by single crystal X-ray diffraction and solid-state UV–vis–NIR absorption spectroscopy. The crystal structure was solved by direct methods with R{sub 1} = 1.26% for 19 unique observed reflections. PuO{sub 2} is cubic, space group Fm3{sup ‾}m, and adopts the fluorite structure type. The lattice parameter was determined to be a = 5.421(5) Å giving a volume of 159.3(2) Å{sup 3}. The absorption spectrum is consistent with Pu(IV)

  19. Synthesis, purification, and characterization of perovskite semiconductor CsPbBr3 as a new candidate for y-ray detector(Conference Presentation)

    Science.gov (United States)

    Chung, Duck Young; Kanatzidis, Mercouri G.; Meng, Fang; Malliakas, Christos D.

    2016-09-01

    CsPbBr3 has direct band gap (orange color, 2.25 eV), high density (4.85 g/cm3), attenuation coefficient comparable to CZT, and high resistivity 10^9 ohm•cm. These fundamental physical properties of CsPbBr3well meet the requirements for gamma-ray detector materials. CsPbBr3 exhibits the carrier mobility-lifetime product in the order of 10^-4 cm2/V promising enough to be further developed for practical applications. The major challenge in the process to further enhance the detection performance is the carrier traps present at a deep level of the energy gap which should be minimized. We report the synthesis, purification, crystal growth and physical characterization of the CsPbBr3 crystals obtained by new processes we developed for highly pure materials with reduced carrier traps. The starting binary materials were prepared by reaction of Cs2CO3/HBr and Pb(ac)2/HBr in aqueous solution. Purification of materials was performed by sublimation, bromination with HBr gas, and filtration of molten materials. Large single crystals were grown by the vertical Bridgman and EelectroDynamic Gradient method and cut to the dimensions appropriate for assessment of the material for gamma-ray detector applications. All characterization including optical characteristics, charge transport properties, photoconductivity, and gamma-ray spectroscopy from the new single crystals of CsPbBr3 will be presented. In addition, the charge carrier traps profile has been studied for this compound by Deep-Level Transient Spectroscopy (DLTS), Thermally Stimulated Luminescence (TSL), and Photoluminescence (PL) and will be presented.

  20. Synthesis and characterization of ZIF-69 membranes and separation for CO2/CO mixture

    KAUST Repository

    Liu, Yunyang; Hu, Enping; Khan, Easir A.; Lai, Zhiping

    2010-01-01

    on crystals taken from the same mother liquor that was used for membrane synthesis yield a Langmuir surface area of 1138 m(2)/g. The stability of the membrane towards heat and different solvents were studied. Single-gas permeation experiments through ZIF-69

  1. Crystal and source characterization for the Crystal Backlighter Imager capability at the National Ignition Facility

    Science.gov (United States)

    Krauland, C. M.; Hall, G. N.; Buscho, J. G.; Hibbard, R.; McCarville, T. J.; Lowe-Webb, R.; Ayers, S. L.; Kalantar, D.; Kohut, T.; Kemp, G. E.; Bradley, D. K.; Bell, P.; Landen, O. L.; Brewster, T. N.; Piston, K.

    2017-10-01

    The Crystal Backlighter Imager (CBI) is a very narrow bandwidth ( 10 eV) x-ray radiography system that uses Bragg reflection from a spherically-curved crystal at near normal incidence. This diagnostic has the capability to image late in an ICF implosion because it only requires the brightness of the backlighter to be larger than the capsule self-emission in that narrow bandwidth. While the limited bandwidth is advantageous for this reason, it also requires that the effective energy of the backlighter atomic line is known to 1 eV accuracy for proper crystal alignment. Any Doppler shift in the line energy must be understood for the imaging system to work. The work presented details characterization experiments done at the Jupiter Laser Facility with a Si (8 6 2) crystal that will be used with a Selenium backlighter in the NIF CBI diagnostic. We used the spherically-bent crystals to image a small ( 200 µm) He α source generated by the Janus laser on a Se foil. Scanning Bragg angles over multiple shots allowed us to map out the spectral line intensity distribution for optimal alignment in NIF. A subsequent Doppler shift measurement using CBI on NIF will also be presented with complementary HYDRA modeling for both experiments. Prepared by LLNL under Contract DE-AC52-07NA27344 and by General Atomics under Contract DE-NA0001808.

  2. Synthesis of anhydrous K2TiOF4 via a mild hydrothermal method

    Science.gov (United States)

    Felder, Justin B.; Yeon, Jeongho; zur Loye, Hans-Conrad

    2015-10-01

    The synthesis of anhydrous K2TiOF4 has been previously attempted by transforming precursor compounds, such as the peroxide (K2Ti(O2)F4), hydrate (K2TiOF4·H2O) and fluoride (K2TiF6). Due to the large structural differences between these precursors and the anhydrous oxyfluorides, however, these preparations have been unsuccessful. Therefore, a direct method of synthesis has been employed to grow single crystals of K2TiOF4 that were characterized by single crystal x-ray diffraction. K2TiOF4 was found to be isostructural with the previously known K2VOF4.

  3. Synthesis and structural characterization of inorganic luminescent materials of Cs2NaErBr6 and Cs2NaHoBr6

    International Nuclear Information System (INIS)

    Poblete, V.H; Fack, G

    2003-01-01

    The synthesis and structural characterization is described of two luminescent materials, with technological [1] and spectroscopic [2] interest, whose crystallographic charts have not been published in the literature. The synthesis of both systems: Cs 2 NaErBr 6 and CS 2 NaHoBr 6 , was done using solid state reactions in a controlled environment. The thermal analyses DTA/TGA, applied with a temperature gradient of 10 o C/min., established crystallization ranges of 490,4 o C to 545,4 o C, for the elpasolite CS 2 NaHoBr 6 and 501 o C to 556 o C, for the structure CS 2 NaErBr 6 .. The heat vacuum treatments were carried out at 505 o C and 526 o C respectively, obtaining optimum crystallization. The structural characterization was performed with powdered X-ray diffraction (XRD). The range between 12 o and 80 o (2θ), was analyzed for 3352 points, measured steps of 0.02 o (2θ using the Rietveld profile refining program. The following crystallographic parameters were established: a 0 = 11,279(1), and 11,293(4) Angstroms, for the two structures analyzed, respectively. The relationship R exp wp in both cases is highly accurate for the 32 test lines that were analyzed. The structures present cubic closed packing Cs 1+ 3 Cl 1- , with Ho 3+ and Er 3+ atoms, filling the octahedral holes. The test data obtained will be very useful for completing the mass of experimental data needed to develop the design engineering, with specific applications for luminescent devices (au)

  4. Synthesis and characterization of reactive dye-cassava mesocarp ...

    African Journals Online (AJOL)

    The synthesis of triazine based reactive dyes was carried out. The resultant dyes were characterized by thin layers chromatography, molecular weight, infrared and ultra- violet spectroscopy, and used in dyeing cassava mesocarp to produce dye modified cellulosic substrates. The dyed substrates were tested for dye fixation, ...

  5. Synthesis, crystal growth and characterization of bioactive material: 2- Amino-1H-benzimidazolium pyridine-3-carboxylate single crystal- a proton transfer molecular complex

    Science.gov (United States)

    Fathima, K. Saiadali; Kavitha, P.; Anitha, K.

    2017-09-01

    The 1:1 molecular adducts 2- Amino-1H-benzimidazolium pyridine-3-carboxylate (2ABPC) was synthesized and grown as single crystal where 2-aminobenzimidazole (ABI) acts as a donor and nicotinic acid (NA) acts as an acceptor. The presence of proton and carbon were predicted using 1H and 13C NMR spectral analysis. The molecular structure of the crystal was elucidated by subjecting the grown crystals to the single crystal x-ray diffraction analysis and was refined by full matrix least-squares method to R = 0.038 for 2469 reflections. The vibrational modes of functional group have been studied using FTIR and Raman spectroscopic analysis. The UV-Vis spectrum exhibited a visible band at 246 nm for 2ABPC due to the nicotinate anion of the molecule. Further, the antimicrobial activity of 2ABPC complex against B. subtilis, klebsiella pneumonia, Pseudomonas eruginos and E. coli pathogens was investigated. Minimum Inhibitory Concentration (MIC) for this crystal was obtained using UV spectrometer against MRSA pathogen. It was found that the benzimidazole with aminogroup at position 2 increases the general antimicrobial activities of 2ABPC crystal.

  6. The role of curvature in silica mesoporous crystals

    KAUST Repository

    Miyasaka, Keiichi

    2012-02-08

    Silica mesoporous crystals (SMCs) offer a unique opportunity to study micellar mesophases. Replication of non-equilibrium mesophases into porous silica structures allows the characterization of surfactant phases under a variety of chemical and physical perturbations, through methods not typically accessible to liquid crystal chemists. A poignant example is the use of electron microscopy and crystallography, as discussed herein, for the purpose of determining the fundamental role of amphiphile curvature, namely mean curvature and Gaussian curvature, which have been extensively studied in various fields such as polymer, liquid crystal, biological membrane, etc. The present work aims to highlight some current studies devoted to the interface curvature on SMCs, in which electron microscopy and electron crystallography (EC) are used to understand the geometry of silica wall surface in bicontinuous and cage-type mesostructures through the investigation of electrostatic potential maps. Additionally, we show that by altering the synthesis conditions during the preparation of SMCs, it is possible to isolate particles during micellar mesophase transformations in the cubic bicontinuous system, allowing us to view and study epitaxial relations under the specific synthesis conditions. By studying the relationship between mesoporous structure, interface curvature and micellar mesophases using electron microscopy and EC, we hope to bring new insights into the formation mechanism of these unique materials but also contribute a new way of understanding periodic liquid crystal systems. © 2012 The Royal Society.

  7. The role of curvature in silica mesoporous crystals

    KAUST Repository

    Miyasaka, Keiichi; Bennett, Alfonso Garcia; Han, Lu; Han, Yu; Xiao, Changhong; Fujita, Nobuhisa; Castle, Toen; Sakamoto, Yasuhiro; Che, Shunai; Terasaki, Osamu

    2012-01-01

    Silica mesoporous crystals (SMCs) offer a unique opportunity to study micellar mesophases. Replication of non-equilibrium mesophases into porous silica structures allows the characterization of surfactant phases under a variety of chemical and physical perturbations, through methods not typically accessible to liquid crystal chemists. A poignant example is the use of electron microscopy and crystallography, as discussed herein, for the purpose of determining the fundamental role of amphiphile curvature, namely mean curvature and Gaussian curvature, which have been extensively studied in various fields such as polymer, liquid crystal, biological membrane, etc. The present work aims to highlight some current studies devoted to the interface curvature on SMCs, in which electron microscopy and electron crystallography (EC) are used to understand the geometry of silica wall surface in bicontinuous and cage-type mesostructures through the investigation of electrostatic potential maps. Additionally, we show that by altering the synthesis conditions during the preparation of SMCs, it is possible to isolate particles during micellar mesophase transformations in the cubic bicontinuous system, allowing us to view and study epitaxial relations under the specific synthesis conditions. By studying the relationship between mesoporous structure, interface curvature and micellar mesophases using electron microscopy and EC, we hope to bring new insights into the formation mechanism of these unique materials but also contribute a new way of understanding periodic liquid crystal systems. © 2012 The Royal Society.

  8. Synthesis and characterization of new optically active poly(amide ...

    African Journals Online (AJOL)

    Synthesis and characterization of new optically active poly(amide-imide)s based on N -trimellitimido- ... Bulletin of the Chemical Society of Ethiopia ... (DMAc), dimethyl sulfoxide (DMSO) and N-methyl-2-pyrrolidone (NMP) at room temperature.

  9. SYNTHESIS, CRYSTAL STRUCTURE AND ANTIOXIDANT POTENTIAL OF DI-(TV-CINNAMYL) FLUOXETINE CHLORIDE

    OpenAIRE

    KANWAL, NOSHEEN; SAHIN, ONUR; HUSAAIN, ERUM A; ULLAHKHAN, ISLAM; BUYUKGUNGOR, ORHAN

    2013-01-01

    A new derivative of Fluoxetine, N,N-dicinnamyl-N-methyl-3-phenyl-3- [4-(trifluoromethyl) phenoxy]butan-1-aminium chloride hydrate [Di-(N-Cinnamyl) Fluoxetine Chloride hydrate] was synthesized and characterized by single-crystal X-ray diffraction studies, elemental analyzer, thermogravimetric and FTIR spectroscopy analysis. The titled compound [C35H37ClF3NO2] crystallized in monoclinic, having unit cell parameters a = 19.155(14) A°, b = 9.193(5) A°, c = 18.596(13) A° and belongs to P2(1)/c spa...

  10. Synthesis and structural characterization of actinide oxalate compounds

    International Nuclear Information System (INIS)

    Tamain, C.

    2011-01-01

    Oxalic acid is a well-known reagent to recover actinides thanks to the very low solubility of An(IV) and An(III) oxalate compounds in acidic solution. Therefore, considering mixed-oxide fuel or considering minor actinides incorporation in ceramic fuel materials for transmutation, oxalic co-conversion is convenient to synthesize mixed oxalate compounds, precursors of oxide solid solutions. As the existing oxalate single crystal syntheses are not adaptable to the actinide-oxalate chemistry or to their manipulation constrains in gloves box, several original crystal growth methods were developed. They were first validate and optimized on lanthanides and uranium before the application to transuranium elements. The advanced investigations allow to better understand the syntheses and to define optimized chemical conditions to promote crystal growth. These new crystal growth methods were then applied to a large number of mixed An1(IV)-An2(III) or An1(IV)-An2(IV) systems and lead to the formation of the first original mixed An1(IV)-An2(III) and An1(IV)-An2(IV) oxalate single crystals. Finally thanks to the first thorough structural characterizations of these compounds, single crystal X-ray diffraction, EXAFS or micro-RAMAN, the particularly weak oxalate-actinide compounds structural database is enriched, which is essential for future studied nuclear fuel cycles. (author) [fr

  11. Graphene synthesis, catalysis with transition metals and their interactions by laser photolysis

    CSIR Research Space (South Africa)

    Mwakikunga, BW

    2011-09-01

    Full Text Available - Graphene ? Synthesis, Characterization, Properties and Applications 60 standing 2D atomic crystals (for example, single-layer boron nitride and half-layer BSCCO [4]). These crystals could be obtained on top of non-crystalline substrates, in liquid... or stacked into 3D graphite [from: Geim and Novoselov, http://arxiv.org/ftp/cond-mat/papers/0702/0702595.pdf] A single atomic plane is a 2D crystal, whereas 100 layers should be considered as a thin film of a 3D material. But how many layers are needed...

  12. Synthesis and characterization of a reduced heteropoly ...

    Indian Academy of Sciences (India)

    Compound (1) crystallizes in a cubic space group 3 ¯ , with = 22.2001(6) Å and = 8. The anion [VVO4W 10 VI V 2 IV O36]7- is a typical Keggin type structure with VVO4 as the central tetrahedron. (1) has further been characterized by elemental analyses, redox titration, IR, EPR, and electronic spectroscopy and room ...

  13. Synthesis, structural and electrical characterizations of thermally ...

    African Journals Online (AJOL)

    Synthesis, structural and electrical characterizations of thermally evaporated Cu 2 SnS 3 thin films. ... The surface profilometer shows that the deposited films are rough. The XRD spectra identified the ... The electrical resistivity of the deposited Cu2SnS3 film is 2.55 x 10-3 Ωcm. The conductivity is in the order of 103 Ω-1cm-1.

  14. Synthesis and Characterization of CdS/CdSxSe1-x Nanowires

    Science.gov (United States)

    Agueda Lopez, Kleyser; Wu, Marvin

    Semiconductor nanowire heterostructures are of interest for potential applications in solar cells and other advanced optoelectronic devices. We report here on synthesis of CdS/CdSxSe1-x nanowires (NWs) using a dual source vapor = liquid - solid technique, and characterization of these NWs with scanning electron microscopy and optical microscopy. We determine the effect of growth parameters, including source / substrate temperatures and time of exposure, on NW size, shape, and composition. The crystal structure and optical properties individual NWs from selected substrates has been mapped using transmission Kikuchi diffraction and photoluminescence (PL) microscopy. NWs consistently exhibit a hexagonal structure, with growth along the c-axis. Strong PL peaks are observed between the expected bandgap emission from CdS and CdSe, confirming formation of CdSxSe1-x. PL peaks vary significantly with intensity along the long axis of the nanowire, suggesting that the NW surface is not uniformly passivated. These nanowires show promise for future investigation and manipulation of energy band gaps contain in CdS/CdSe. CREST.

  15. Ultrasonic characterization of pork fat crystallization during cold storage.

    Science.gov (United States)

    Corona, Edith; García-Pérez, José V; Santacatalina, Juan V; Ventanas, Sonia; Benedito, José

    2014-05-01

    In this work, the feasibility of using ultrasonic velocity measurements for characterizing and differentiating the crystallization pattern in 2 pork backfats (Montanera and Cebo Iberian fats) during cold storage (0 °C, 2 °C, 5 °C, 7 °C, and 10 °C) was evaluated. The fatty acid profile, thermal behavior, and textural properties (hardness) of fat were also determined. Both fats became harder during cold storage (average hardness increase for both fats, 11.5 N, 8 N, and 1.8 N at 0, °C 2 °C, and 5 °C , respectively), showing a 2-step pattern related with the separate crystallization of the different existing triacylglycerols, which was well described using a modified Avrami equation (explained variance > 99%). Due to a greater content of saturated triacylglycerols, Cebo fat (45.1%) was harder than Montanera (41.8%). The ultrasonic velocity followed a similar 2-step pattern to hardness during cold storage, being found an average increase for both fats of 184, 161, and 150 m/s at 0 °C 2 °C, and 5 °C, respectively. Thus, ultrasonic measurements were useful both to characterize the textural changes taking place during cold storage and to differentiate between fats with different composition. The cold storage of dry-cured meat products during their distribution and retail sale exert an important effect on their textural properties and consumers' acceptance due to the crystallization of the fat fraction, which is greatly influenced by the type of fat. In this work, a nondestructive ultrasonic technique was used to identify the textural changes provoked by the crystallization during cold storage, and to differentiate between fats, which could be used for quality control purposes. © 2014 Institute of Food Technologists®

  16. Combustion synthesis and structural characterization of Li–Ti mixed

    Indian Academy of Sciences (India)

    Combustion synthesis and structural characterization of Li–Ti mixed nanoferrites ... were prepared by combustion method at lower temperatures compared to the ... first time at low temperatures, using PEG which acts as a new fuel and oxidant.

  17. Synthesis, crystal structure and characterization of a new organic-inorganic hybrid material 4-(ammonium methyl) pipyridinium hexachloro stanate (II) trihydrate

    Science.gov (United States)

    Lassoued, Mohamed Saber; Abdelbaky, Mohammed S. M.; Lassoued, Abdelmajid; Ammar, Salah; Gadri, Abdellatif; Ben Salah, Abdelhamid; García-Granda, Santiago

    2018-03-01

    The present paper undertakes the study of (C6H16N2) SnCl6·3H2O which is a new hybrid compound. It was prepared and characterized by single crystal X-ray diffraction, X-ray powder, Hirshfeld surface, Spectroscopy measurement, thermal study and photoluminescence properties. The single crystal X-ray diffraction studies revealed that the compound crystallizes in monoclinic Cc space group with cell parameters a = 8.3309(9) Å, b = 22.956(2) Å, c = 9.8381(9) Å, β = 101.334(9) ° and Z = 4. The atomic arrangement shows an alternation of organic and inorganic entities. The cohesion between these entities is performed via Nsbnd H⋯Cl, Nsbnd H⋯O, Osbnd H⋯Cl and Osbnd H⋯O hydrogen bonding to form a three-dimensional network. Hirshfeld surface analysis was used to investigate intermolecular interactions, as well 2D finger plots were conducted to reveal the contribution of these interactions in the crystal structure quantitatively. The X-ray powder is in agreement with the X-ray structure. Scanning electron microscope (SEM) was carried out. Furthermore, the room temperature infrared (IR) spectrum of the title compound was recorded and analyzed on the basis of data found in the literature. Solid state 13C NMR spectrum shows four signals, confirming the solid state structure determined by X-ray diffraction. Besides, the thermal analysis studies were performed, but no phase transition was found in the temperature range between 30 and 450 °C. The optical and PL properties of the compound were investigated in the solid state at room temperature and exhibited three bands at 348 and 401 cm-1 and a strong fluorescence at 480 nm.

  18. The growth of high density network of MOF nano-crystals across macroporous metal substrates - Solvothermal synthesis versus rapid thermal deposition

    Science.gov (United States)

    Maina, James W.; Gonzalo, Cristina Pozo; Merenda, Andrea; Kong, Lingxue; Schütz, Jürg A.; Dumée, Ludovic F.

    2018-01-01

    Fabrication of metal organic framework (MOF) films and membranes across macro-porous metal substrates is extremely challenging, due to the large pore sizes across the substrates, poor wettability, and the lack of sufficient reactive functional groups on the surface, which prevent high density nucleation of MOF crystals. Herein, macroporous stainless steel substrates (pore size 44 × 40 μm) are functionalized with amine functional groups, and the growth of ZIF-8 crystals investigated through both solvothermal synthesis and rapid thermal deposition (RTD), to assess the role of synthesis routes in the resultant membranes microstructure, and subsequently their performance. Although a high density of well interconnected MOF crystals was observed across the modified substrates following both techniques, RTD was found to be a much more efficient route, yielding high quality membranes under 1 h, as opposed to the 24 h required for solvothermal synthesis. The RTD membranes also exhibited high gas permeance, with He permeance of up to 2.954 ± 0.119 × 10-6 mol m-2 s-1 Pa-1, and Knudsen selectivities for He/N2, Ar/N2 and CO2/N2, suggesting the membranes were almost defect free. This work opens up route for efficient fabrication of MOF films and membranes across macro-porous metal supports, with potential application in electrically mediated separation applications.

  19. Synthesis, crystal structure and magnetic characterization of a cyanide-bridged Mo-Ni nanosized molecular wheel

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Daopeng; Zhang, Hongyan; Wang, Ping [Shandong Univ. of Technology, College of Chemical Engineering, Zibo (China); Kong, Lingqian [Liaocheng Univ. (China). Dongchang College

    2015-11-01

    By using K{sub 4}[Mo(CN){sub 8}] and [Ni(L)(H{sub 2}O){sub 2}][ClO{sub 4}]{sub 2} as reagents (L = 2,12-dimethyl-3,7,11,17-tetraazabicyclo [11.3.1]heptadeca-1(17),13,15-triene), a new cyanide-bridged Mo-Ni complex containing the building blocks [Ni(H{sub 2}O)(L)]{sup 2+} and [Ni(L)]{sup 2+} bridged by [Mo(CN){sub 8}]{sup 4-} units has been obtained. The complex with the formula {[Ni(H_2O)(L)][Ni(L)][Mo(CN)_8]}{sub 6} . 36H{sub 2}O . 2CH{sub 3}OH (1) was characterized by elemental analysis, IR spectroscopy and single-crystal X-ray diffraction. The structure determination reveals an octadecanuclear cluster in the form of a 36-membered macrocycle, in which the largest intramolecular W..W and Ni..Ni distances are 16.5 and 14.4 Aa, respectively, indicating that complex 1 is a nanosized molecular wheel. Investigation of its magnetic properties has shown weak antiferromagnetic coupling between the adjacent Ni(II) ions bridged by the diamagnetic [Mo(CN){sub 8}]{sup 4-} ions.

  20. Crystal structure, characterization and magnetic properties of a 1D ...

    Indian Academy of Sciences (India)

    Crystal structure, characterization and magnetic properties of a 1D copper(II) polymer incorporating a Schiff base with carboxylate side arm. SHYAMAPADA SHIT MADHUSUDAN NANDY CORRADO RIZZOLI CÉDRIC DESPLANCHES SAMIRAN MITRA. Regular Article Volume 128 Issue 6 June 2016 pp 913-920 ...

  1. Synthesis and structural characterization of amorphous alloys of the Fe-Ni-B type

    International Nuclear Information System (INIS)

    Cabral P, A.; Jimenez B, J.; Garcia S, I.

    2004-01-01

    It was prepared the alloy FeNiB for chemical reduction, using four p H values (5, 6, 7 and 7.5). To p H=6 partially oxidized particles were obtained, between 16 and 20%. In the synthesis to other p H values, the obtained particles were highly oxidized (65-90%) according to the X-ray diffraction results, in all the preparations the particles were partially crystallized, with crystal size that varied between 4 and 10 nm. The structure of these particles can be consider that they are formed by a nucleus due to the alloy and an oxide armor recovering it. (Author)

  2. Synthesis, structural characterization and antitumor activity of a Ca(II) coordination polymer based on 4-formyl-1,3-benzenedisulfonate-2-furoic acid hydrazide ligands

    Energy Technology Data Exchange (ETDEWEB)

    Tai, Xi-Shi, E-mail: taixs@wfu.edu.cn [Weifang University, College of Chemistry and Chemical Engineering (China); Wang, Xin [Qinghai Normal University, Department of Chemistry (China)

    2017-03-15

    A new Ca(II) coordination polymer, ([CaL(H{sub 2}O){sub 4}] · (H{sub 2}O){sub 4}){sub n} (L = 4-formyl-1,3-benzenedisulfonate-2-furoic acid hydrazide) has been prepared by one-pot synthesis method. And it was characterized by elemental analysis, IR and thermal analysis. The result of X-ray single-crystal diffraction analysis shows that the Ca(II) complex molecules form one-dimensional chain structure by the bridging oxygen atoms. The anti-tumor activity of L ligand and the Ca(II) coordination polymer has also been studied.

  3. Synthesis of formamidinium lead iodide perovskite bulk single crystal and its optical properties

    Science.gov (United States)

    Zheng, Hongge; Duan, Junjie; Dai, Jun

    2017-07-01

    Formamidinium lead iodide (FAPbI3) is a promising hybrid perovskite material for optoelectronic devices. We synthesized bulk single crystal FAPbI3 by a rapid solution crystallization method. X-ray diffraction (XRD) was performed to characterize the crystal structure. Temperature-dependent photoluminescence (PL) spectra of the bulk single crystal FAPbI3 were measured from 10 to 300 K to explain PL recombination mechanism. It shows that near band edge emission blueshifts with the temperature increasing from 10 to 120 K and from 140 K to room temperature, a sudden emission band redshift demonstrates near 140 K because of the phase transition from orthorhombic phase to cubic phase. From the temperature-dependent PL spectra, the temperature coefficients of the bandgap and thermal activation energies of FAPbI3 perovskite are fitted.

  4. Synthesis, characterization and magnetic properties of selected Laves and MAX phases

    International Nuclear Information System (INIS)

    Hamm, Christin Maria

    2017-01-01

    In this work the rare-earth free Laves phases Ti 2 M 3 Si with M = Mn, Fe, Co, Ni were synthesized by microwave heating and were structurally and magnetically characterized. Furthermore, the solid solution Ti 2 (Co 1-x Fe x ) 3 Si was synthesized by arc melting and spark plasma sintering, as well as their magnetic behavior was studied. In addition to the Laves phases, the focus was on the synthesis and characterization of aluminum-based MAX phases. For the first time the ternary carbides were prepared by microwave heating. The phase-pure representation of MAX phases was particularly challenging for synthetic solid-state chemistry. The susceptor-assisted microwave heating allows the synthesis of high-quality samples, which was shown in this work on M 2 AlC (M = Ti, V, Cr) and V 4 AlC 3 . Furthermore, for the first time, the doping of these materials with Mn and Fe was successful. In addition to the structural characterization of the new phases, the microstructure and magnetic properties are discussed in this work. Using these doped compounds as well as the compound V 4 AlC 3 , it has been shown that field-activated synthesis, particularly susceptor-assisted microwave heating, are a very good synthesis method for compounds which are hard or sometimes not synthesized by conventional methods.

  5. Characterization of Crystals for Steering of Protons through Channelling in Hadronic Accelerators

    CERN Document Server

    Guidi, V; Boscolo-Marchi, E; Carnera, A; Chesnokov, Yu A; Della Mea, G; De Salvador, D; Fiorini, M; Ivanov, Y M; Martinelli, G; Mazzolari, A; Milan, E; Milan, R; Sambo, A; Scandale, Walter; Todros, S; Vomiero, A

    2006-01-01

    Channeling of relativistic particles through a crystal may be useful for many applications in accelerators, and particularly for collimation in hadronic colliders. Efficiency proved to be dependent on the state of the crystal surface and hence on the method used for preparation. We investigated the morphology and structure of the surface of the samples that have been used in accelerators with high efficiency. We found that crystal fabrication by only mechanical methods (dicing, lapping, and others) leads to a superficial damaged layer, which is correlated to performance limitation in accelerators. A planar chemical etching was studied and applied in order to remove the superficial damaged layer. RBS channeling analysis with low-energy protons and 4He+ highlighted better crystal perfection at surface, as a result of the etching. A protocol for preparation and characterization of crystal for channelling has been developed, which may be of interest for reliable operation with crystals in accelerators.

  6. Optimization of MCM-48 synthesis using factorial design

    Energy Technology Data Exchange (ETDEWEB)

    Nascimento, A.R. do; Medeiros, R.L.B. de A.; Melo, M. A. de F.; Melo, D.M. de A. [Universitdade Federal do Rio Grande do Norte (UFRN), Natal (Brazil); Souza, M.J.B. de, E-mail: ale3ufs@yahoo.com.br [Universidade Federal de Sergipe (UFS), Sao Cristovao (Brazil)

    2016-10-15

    MCM-48 mesoporous materials were hydrothermally synthesized according to the 2{sup 2} factorial design by varying the crystallization time and temperature of the synthesis gel, and characterized by means of X-ray diffraction analysis and adsorption of N{sub 2} . In the crystallization temperature and time conditions used, specific areas between 924 to 1102 m{sup 2}.g{sup -1}, pore volumes between 0.015 to 0.087 cm{sup 3}.g{sup -1} and pore diameters between 3.2 to 4.0 nm were obtained. It was observed that for the syntheses performed at high temperature, the crystallization time should be reduced so that the material structure is formed. (author)

  7. Growth and characterization of La2CoMnO6 crystals doped with Pb

    International Nuclear Information System (INIS)

    Milenov, T.I.; Rafailov, P.M.; Abrashev, M.V.; Nikolova, R.P.; Nakatsuka, A.; Avdeev, G.V.; Veleva, M.N.; Dobreva, S.; Yankova, L.; Gospodinov, M.M.

    2010-01-01

    Crystals of La 2 CoMnO 6 doped with Pb were grown by the high temperature solution growth method. Several crystals were examined by scanning electron microscopy (SEM), energy-dispersive X-ray analysis (EDAX), X-ray single-crystal diffractometry and polarized Raman spectroscopy. Some variations in the composition of different crystals are observed, however, within the volume of each distinct crystal the composition is found to be fairly constant. Crystals with lateral dimensions larger than 2 mm and thicker than 1 mm contain structural defects as twin lamellae and surface roughness. The results from the characterization of the grown crystals with X-ray diffraction and Raman spectroscopy are consistent with an assumption for a coexistence of an ordered monoclinic and a disordered orthorhombic phase.

  8. Synthesis and characterization of cadmium doped lead–borate ...

    Indian Academy of Sciences (India)

    Unknown

    Mater. Sci., Vol. 29, No. 1, February 2006, pp. 55–58. © Indian Academy of Sciences. 55. Synthesis and characterization of cadmium doped lead–borate glasses. A A ALEMI*, H SEDGHI†, A R MIRMOHSENI and V GOLSANAMLU. Department of Inorganic Chemistry, Faculty of Chemistry, University of Tabriz, Tabriz, Iran.

  9. Synthesis and electrochemical characterization of nano-sized Ag_4Sn particles as anode material for lithium-ion batteries

    International Nuclear Information System (INIS)

    Schmuelling, Guido; Oehl, Nikolas; Fromm, Olga; Knipper, Martin; Kolny-Olesiak, Joanna; Plaggenborg, Thorsten; Parisi, Jürgen; Winter, Martin; Placke, Tobias

    2016-01-01

    For the first time, sub 10 nm sized intermetallic Ag_4Sn particles are prepared via an aqueous synthesis route in order to improve the electrochemical performance of pure Sn nanoparticles. High-resolution transmission electron microscopy, X-ray diffraction and thermogravimetric analysis are used to investigate the morphology, crystal structure and particle surface of the as prepared Ag_4Sn nanoparticles. In addition, galvanostatic cycling and cyclic voltammetry measurements are carried out to characterize the electrochemical behavior of the particles. Upon lithiation and de-lithiation a phase transformation from Ag_4Sn to Ag_3Sn is observed, which has not been reported so far. The intermetallic nanoparticle-based anode delivers a specific de-lithiation capacity of 460 mAhg"−"1 for more than 150 cycles.

  10. Synthesis and magnetic characterization of LaMnO{sub 3} nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez, E.; Sagredo, V. [Universidad de Los Andes, Facultad de Ciencias, Laboratorio de Magnetismo, 5101 Merida (Venezuela, Bolivarian Republic of); Delgado, G. E. [Universidad de Los Andes, Facultad de Ciencias, Laboratorio de Cristalografia, 5101 Merida (Venezuela, Bolivarian Republic of)

    2015-07-01

    LaMnO{sub 3} nanoparticles system were prepared by the sol-gel auto-combustion method, in order to analyze the structure and magnetic behavior presented by the compound prepared following a new alternative route of synthesis. Structural characterization, morphology and crystallite size was performed by X-ray diffraction (XRD), infrared spectroscopy (IR) and electron microscopy. The XRD study together with a Rietveld analysis showed that the LaMnO{sub 3} compound crystallized in a perovskite hexagonal structure. The IR spectra showed that the compound has tensile energy bands in the Mn-O-Mn bonds related with the octahedron MnO{sub 6}; which are attributed to a characteristic vibration of the ABO{sub 3} perovskite. An estimated size and morphological analysis was carried out by applying the Scherrer formula and using transmission electron microscopy, revealing non-spherical shape and particle sizes between 13 nm and 18 nm. The magnetic measurements M(T) were performed by using zero field-cooled and field-cooled protocols which revealed a positive Weiss temperature indicating the presence of ferromagnetic interactions with a Curie temperature, T{sub C} = 150 K. (Author)

  11. Spectroscopic studies, theoretical models and structural characterization. II. Synthesis and X-ray powder diffraction of the elpasolites Cs2NaSmCl6

    International Nuclear Information System (INIS)

    Poblete, V.; Acevedo, R.

    1998-01-01

    In this research work, we report the synthesis and structural characterization of the stoichiometric elpasolite Cs 2 NaSmCl 6 . The synthesis was performed under a solid state reaction in nitrogen atmosphere from the chemicals CsCl, NaCl and SmCl 3 weighted stoichiometrically. The best possible crystallization temperature was obtained using thermal studies of the type DTA/TGA (the thermal treatment was allowed to proceed for 2.5 hours at 755 Centigrade, showing a temperature gradient of 10 Centigrade/minute). The structural characterization by powder X-ray diffraction (XDR) indicates that this elpasolite belongs to the Fm 3m (O h 5 ) space group and the optimized structural parameters are as follows: a 0 = 10.8342 Armstrong, V 1271.72 Armstrong 3 , Z=4, M=651.88, D x =3.406 y D exp=3.41 ± 0.01. The profile refinement, using the Rietveld method, allowed us to fit the experimental and the calculated intensities of a total of 32 lines. The above result indicates that the condition R exp 2+ + 3Cl -1 and the counter ions filling the octahedral holes, in full agreement with anti fluorite type crystal. According to the above description, these elpasolite adopt the form (M 1/3 □ 2/3 ) 4 X 2 , where M labels the central metal, X stand for the chlorine ions and □ represent the vacancies, which may accommodate a significant amount of defects without collapsing. This experimental study provides the necessary input to test theoretical models against experimental data. (Author)

  12. Facile synthesis, single crystal analysis, and computational studies of sulfanilamide derivatives

    Science.gov (United States)

    Tahir, Muhammad Nawaz; Khalid, Muhammad; Islam, Ayesha; Ali Mashhadi, Syed Muddassir; Braga, Ataualpa A. C.

    2017-01-01

    Antibacterial resistance is a worldwide problem. Sulfanilamide is widely used antibacterial. For the first time, we report here a simple method for the derivative synthesis of the title drugs, single crystal XRD and density functional theory (DFT) studies. The optimized molecular structure, natural bond orbital (NBO), frontier molecular orbitals (FMOs) molecular electrostatic potential studies (MEP) and Mulliken population analysis (MPA) have been performed using M06-2X/6-31G(d, p). The FT-IR spectra and thermodynamic parameters were calculated at M06-2X/6-311 + G(2d,p) and B3LYP/6-31G(d, p) levels respectively, while, the UV-Vis analysis was performed using TD-DFT/B3LYP/6-31G(d, p) method. The experimental FT-IR spectra of both compounds were also carried out to reconfirm sbnd H⋯Osbnd hydrogen bonds. The DFT optimized parameters exhibiting good agreement with the experimental data. NBO analysis explored the hyper conjugative interaction and stability of title crystals, especially, reconfirmed the existence of sbnd H⋯Osbnd hydrogen bonds between the dimers. The FT-IR, thermodynamic parameters, MEP and MPA also revealed the hydrogen bonding detail is harmonious to XRD data. As a matter of the fact, the hydrogen bonding is a significant parameter for the understanding and design of molecular crystals, subsequently; it can also play a vital role in the supramolecular chemistry. Moreover, the global reactivity descriptors suggest that title compounds might be bioactive.

  13. Electrochemical synthesis and characterization of stable colloidal suspension of graphene using two-electrode cell system

    Energy Technology Data Exchange (ETDEWEB)

    Danial, Wan Hazman, E-mail: hazmandanial@gmail.com; Majid, Zaiton Abdul, E-mail: zaiton@kimia.fs.utm.my; Aziz, Madzlan [Department of Chemistry, Faculty of Science, Universiti Teknologi Malaysia (UTM), 81310 Skudai, Johor (Malaysia); Chutia, Arunabhiram [Institute of Fluid Sciences, Tohoku University, Sendai 980-8577 (Japan); Sahnoun, Riadh [Ibnu Sina Institute for Fundamental Science Studies, Universiti Teknologi Malaysia (UTM), 81310 Skudai, Johor (Malaysia)

    2015-07-22

    The present work reports the synthesis and characterization of graphene via electrochemical exfoliation of graphite rod using two-electrode system assisted by Sodium Dodecyl Sulphate (SDS) as a surfactant. The electrochemical process was carried out with sequence of intercalation of SDS onto the graphite anode followed by exfoliation of the SDS-intercalated graphite electrode when the anode was treated as cathode. The effect of intercalation potential from 5 V to 9 V and concentration of the SDS surfactant of 0.1 M and 0.01 M were investigated. UV-vis Spectroscopic analysis indicated an increase in the graphene production with higher intercalation potential. Transmission Electron Microscopy (TEM) analysis showed a well-ordered hexagonal lattice of graphene image and indicated an angle of 60° between two zigzag directions within the honeycomb crystal lattice. Raman spectroscopy analysis shows the graphitic information effects after the exfoliation process.

  14. Synthesis, crystal structures and properties of lead phosphite compounds

    International Nuclear Information System (INIS)

    Song, Jun-Ling; Hu, Chun-Li; Xu, Xiang; Kong, Fang; Mao, Jiang-Gao

    2015-01-01

    Here, we report the preparation and characterization of two lead(II) phosphites, namely, Pb_2(HPO_3)_2 and Pb_2(HPO_3)(NO_3)_2 through hydrothermal reaction or simple solution synthesis, respectively. A new lead phosphite, namely, Pb_2(HPO_3)_2, crystallizes in the noncentrosymmetric space group Cmc2_1 (no. 36), which features 3D framework formed by the interconnection of 2D layer of lead(II) phosphites and 1D chain of [Pb(HPO_3)_5]_∞. The nonlinear optical properties of Pb_2(HPO_3)(NO_3)_2 have been studied for the first time. The synergistic effect of the stereo-active lone-pairs on Pb"2"+ cations and π-conjugated NO_3 units in Pb_2(HPO_3)(NO_3)_2 produces a moderate second harmonic generation (SHG) response of ∼1.8×KDP (KH_2PO_4), which is phase matchable (type I). IR, UV–vis spectra and thermogravimetric analysis (TGA) for the two compounds were also measured. - Graphical abstract: Two lead phosphites Pb_2(HPO_3)_2 and Pb_2(HPO_3)(NO_3)_2 are studied. A new lead phosphite Pb_2(HPO_3)_2 features a unique 3D framework structure and Pb_2(HPO_3)(NO_3)_2 shows a moderate SHG response of ∼1.8×KDP (KH_2PO_4). - Highlights: • A new lead phosphite, Pb_2(HPO_3)_2 is reported. • Pb_2(HPO_3)_2 features a unique 3D framework structure. • NLO property of Pb_2(HPO_3)(NO_3)_2 is investigated. • Pb_2(HPO_3)(NO_3)_2 produces a moderate SHG response of ∼1.8×KDP (KH_2PO_4).

  15. Synthesis and characterization of nanometer sized thermoelectric lead-antimony-silver-tellurium compounds and related materials

    International Nuclear Information System (INIS)

    Petri, Denis

    2012-01-01

    The present dissertation deals with different variants of synthesis and processing of nanocrystalline composites of various thermoelectric compounds based on lead telluride including LAST-m (AgPb m SbTe m+2 ), LASTT-m-x (AgPb m-x Sn x SbTe m+2 ), LABST-m-x (AgPb m Sb 1-x Bi x Te m+2 ), doped LAST-m and (PbTe) m (M 15 2 Te 3 ) and the characterization thereof. A new route of manufacturing nanocrystalline composites was developed. The so called co-ball milling-route includes the synthesis of bi- or multinary compounds by conventional solid state melting methods followed by combined milling of appropriate amounts in a planetary ball mill; a process related to the widely used mechanical alloying of elemental powders. The as produced powders were shortly annealed for one hour and a.erwards compacted either at room temperature followed by pressureless sintering or combined application of high pressure and elevated temperatures via spark-plasma-sintering or short-term-sintering. The ball milling yielded micron-sized agglomerates consisting of crystallites with diameters ranging from 10 to 50 nm. These crystallites exhibited complicated internal nanostructures severe crystal defects as a consequence of the high energy processing. During short-term annealing some grain coarsening occured and the crystal defects partly healed, which was confirmed by TEM and HRTEM investigations as well as profile analysis of XRD powder pattern. Local EDX-analysis showed different compositions at every point as a consequence of synthesis and decomposition of the compounds. Measurements of thermopower, electrical and thermal conductivity were carried out and the values of the figure of merit ZT and the powerfactor were calculated. In general the compounds exhibited larger thermopower than corresponding bulk materials, which might be attributed to energy filtering of charge carriers at partly oxidized grain boundaries. Due to enhanced phonon scattering at grain boundarys, nanoscopic

  16. Synthesis, structural characterization, and thermal stability studies of heteroleptic cadmium(II) dithiocarbamate with different pyridyl groups

    Science.gov (United States)

    Onwudiwe, Damian C.; Hosten, Eric C.

    2018-01-01

    The synthesis, characterization and crystal structures of three chloroform solvated adducts of cadmium with mixed ligands of N-alkyl-N-phenyldithiocarbamate and pyridine, 2,2-bipyridine and 1, 10 phenanthroline represented as [CdL1L2 (py)2]·CHCl3(1), [CdL1L2bpy]•CHCl3(2), and [CdL1L2phen]•CHCl3(3) (LI = N-methyl-N-phenyldithiocarbamate, L2 = N-ethyl-N-phenyldithiocarbamate, py = pyridine, bpy = 2,2-bipyridine and phen = 1,10-phenanthroline) respectively are reported. Complex 1, which crystallized in the monoclinic space group P-1, is a centrosymmetric dimeric structure where each Cd center is bonded to two monodentate pyridine, a bidentate terminal dithiocarbamate, and another bidentate bridging dithiocarbamate to form a four-membered ring. Complex 2 crystallized in the monoclinic space group P21/c, with four discrete monomeric molecules in the asymmetric unit. The structure presents a cadmium atom coordinated by two sulphur atoms of a dithiocarbamate ligand and two nitrogen atoms of the 2,2‧-bipyridine to form a CdS4N2 fragment, thus giving the structure around the Cd atom a distorted trigonal prism geometry. Complex 3 contains two discrete monomeric molecules of (phenanthroline) (N, N-methyl phenyl-N, N-ethyl phenyl dithiocarbamato)cadmium (II) per unit cell, and the complex crystallized in the triclinic space group P-1. The structure showed that the Cd atom is bonded to two bidentate dithiocarbamate ligands and to one bidentate phenanthroline ligand in a distorted trigonal prism geometry. All the compounds resulted in CdS as residue upon thermal decomposition process conducted under inert atmosphere.

  17. Synthesis, spectroscopic characterization, biological screenings, DNA binding study and POM analyses of transition metal carboxylates

    Science.gov (United States)

    Uddin, Noor; Sirajuddin, Muhammad; Uddin, Nizam; Tariq, Muhammad; Ullah, Hameed; Ali, Saqib; Tirmizi, Syed Ahmed; Khan, Abdur Rehman

    2015-04-01

    This article contains the synthesis of a novel carboxylic acid derivative, its transition metal complexes and evaluation of biological applications. Six carboxylate complexes of transition metals, Zn(II) and Hg(II), have been successfully synthesized and characterized by FT-IR and NMR (1H, 13C). The ligand, HL, (4-[(2,6-Diethylphenyl)amino]-4-oxobutanoic acid) was also characterized by single crystal X-ray analysis. The complexation occurs via oxygen atoms of the carboxylate moiety. FT-IR date show the bidentate nature of the carboxylate moiety of the ligand as the Δν value in all complexes is less than that of the free ligand. The ligand and its complexes were screened for antifungal and antileishmanial activities. The results showed that the ligand and its complexes are active with few exceptions. UV-visible spectroscopy and viscometry results reveal that the ligand and its complexes interact with the DNA via intercalative mode of interaction. A new and efficient strategy to identify the pharmacophores and anti-pharmacophores sites in carboxylate derivatives for the antibacterial/antifungal activity using Petra, Osiris and Molinspiration (POM) analyses was also carried out.

  18. Synthesis and characterization of new ionic liquids

    International Nuclear Information System (INIS)

    Oliveira, L.M.C. de; Mattedi, S.; Boaventura, J.S.; Iglesias, M.; Universidad de Santiago de Compostela

    2010-01-01

    In recent years, ionic liquids have been highlighted for its potential in various industrial applications. Among them, the salts of Broensted has a promising profile for the low toxicity, low cost and simple synthesis. This paper presents the synthesis and characterization of new salts of Bronsted with branched (lactate) or large chain anions (oleate) for future use as additives promoters of proton conductivity in fuel cells of ethanol. Experimental data were measured for density, sound velocity and conductivity of pure ionic liquids and mixtures. The density decreases linearly with increasing temperature, and sound velocity shows a similar trend, but not linear. The conductivity increases according to the Arrhenius model with activation energy less than 10 J/mol. Tests NMR, FTIR and TGA confirm ionic structure and thermal stability up to 165 deg C. (author)

  19. Solvent-induced controllable synthesis, single-crystal to single-crystal transformation and encapsulation of Alq3 for modulated luminescence in (4,8)-connected metal-organic frameworks.

    Science.gov (United States)

    Lan, Ya-Qian; Jiang, Hai-Long; Li, Shun-Li; Xu, Qiang

    2012-07-16

    In this work, for the first time, we have systematically demonstrated that solvent plays crucial roles in both controllable synthesis of metal-organic frameworks (MOFs) and their structural transformation process. With solvent as the only variable, five new MOFs with different structures have been constructed, in which one MOF undergoes solvent-induced single-crystal to single-crystal (SCSC) transformation that involves not only solvent exchange but also the cleavage and formation of coordination bonds. Particularly, a significant crystallographic change has been realized through an unprecedented three-step SCSC transformation process. Furthermore, we have demonstrated that the obtained MOF could be an excellent host for chromophores such as Alq3 for modulated luminescent properties.

  20. Synthesis, characterization and biocompatibility evaluation of hydroxyapatite - gelatin polyLactic acid ternary nanocomposite

    Directory of Open Access Journals (Sweden)

    Z. Nabipour

    2016-04-01

    Full Text Available Objective(s: The current study reports the production and biocompatibility evaluation of a ternary nanocomposite consisting of HA, PLA, and gelatin for biomedical application.Materials and Methods: Hydroxyapatite nanopowder (HA: Ca10(PO46(OH2 was produced by burning the bovine cortical bone within the temperature range of 350-450 oC followed by heating in an oven at 800. Synthesis of the ternary nanocomposite was carried out in two steps: synthesis of gelatin-hydroxyapatite binary nanocomposite and addition of poly lactic acid with different percentages to the resulting composition. The crystal structure was determined by X-ray diffraction (XRD, while major elements and impurities of hydroxyapatite were identified by elemental analysis of X-ray fluorescence (XRF. Functional groups were determined by Fourier transform infrared spectroscopy (FTIR. Morphology and size of the nanocomposites were evaluated using field emission scanning electron microscope (FE-SEM.Biocompatibility of nanocomposites was investigated by MTT assay. Results: XRD patterns verified the ideal crystal structure of the hydroxyapatite, which indicated an appropriate synthesis process and absence of disturbing phases. Results of FTIR analysis determined the polymers’ functional groups, specified formation of the polymers on the hydroxyapatite surface, and verified synthesis of nHA/PLA/Gel composite. FESEM images also indicated the homogeneous structure of the composite in the range of 50 nanometers. MTT assay results confirmed the biocompatibility of nanocomposite samples.Conclusion: This study suggested that the ternary nanocomposite of nHA/PLA/Gel can be a good candidate for biomedical application such as drug delivery systems, but for evaluation of its potential in hard tissue replacement, mechanical tests should be performed.

  1. Synthesis, characterization, and molecular structure of tetraethylammonium pentakis(isothiocyanato)bis(2,2'-bipyridine)uranate(IV)

    International Nuclear Information System (INIS)

    Wiley, R.O.; Von Dreele, R.B.; Brown, T.M.

    1980-01-01

    The synthesis of tetraethylammonium pentakis(isothiocyanato)bis(2,2'-bipyridine)uranate(IV) has been accomplished, and it was characterized by classical physical methods. The crystal and molecular structure was determined from single-crystal x-ray data collected by the theta-2theta technique on an automated diffractometer. The compound consists of pentakis(isothiocyanato)bis (2,2'-bipyridine)uranate(IV) anions and disordered tetraethylammonium cations. Uranium is bound to nine nitrogen atoms in a highly distorted monocapped square antiprism in which one bipyridine occupies a position bridging the cap and the near square while the other bipyridine spans the opposite edge of the far square. Distortion from the ideal geometry is caused by the small ligand bite of the bipyridine ligand. An alternative description of the coordination geometry is derived from the seven-coordinate pentagonal bipyramid in which each bipyridine ligand is assumed to occupy an axial position with the five thiocyanato ligands forming the pentagonal girdle. The U-N bond distances vary from 2.35 to 2.47 A for the thiocyanato ligands and from 2.61 to 2.65 A for the bipyridine ligands. The structure was solved by standard heavy-atom techniques and refined by large-block matrix least squares to a final R value of 0.083 for 3878 independent observed reflections. The compound crystallized in the monoclinic space group P2 1 /c, Z = 4, with lattice parameters a = 14.427 (10) A, b = 18.612 (17) A, c = 15.710 (10) A, and β = 105.17 (7) 0 , rho/sub obsd/ = 1.57 g cm -3

  2. Synthesis and characterization of a-site doped LaTiO3 nano perovskites

    International Nuclear Information System (INIS)

    Bradha, M.; Ashok, Anuradha

    2013-01-01

    Nano-sized lanthanum titanate perovskites (La (1-x) A x TiO 3 ) (A= Ba, Sr, Ca) were prepared by sol-gel method and calcined at 800℃. The synthesised perovskites were characterized by Thermogravimetry/ Differential thermal analysis (TGA/DTA), X-ray diffraction (XRD) and High Resolution Transmission Electron Microscopy (HRTEM) etc. LaTiO 3 is a perovskite having prominent interest for a variety of applications such as dielectric, insulators, charge-transport properties etc. It is a defect perovskite, with transport properties varying from insulating to metallic based on oxygen stoichiometry. In a quest to observe the effect of the nano size on its properties, lanthanum titanate (LaTiO 3 ) nano perovskites with different dopants on the A-site were prepared by using sol-gel method. In the present work we discuss the synthesis and structural analysis of (La 0.8 A 0.2 TiO 3 ). Phase purity and structural analysis of the calcined samples were performed by powder X-ray diffraction (XRD, with CuKα radiation). In addition to this, morphology and crystal structure was examined by Transmission Electron Microscopy (TEM) using a JEOL JEM 2100 HRTEM. HRTEM studies indicate that the nano perovskites are of size around 20 nm. Ring pattern in SAED also confirms that the perovskite is polycrystalline/nanocrystalline. More detailed study on high resolution images and crystal structure shed light on the reason for the properties exhibited by this perovskites

  3. Structural Characterization of Doped GaSb Single Crystals by X-ray Topography

    Energy Technology Data Exchange (ETDEWEB)

    Honnicke, M.G.; Mazzaro, I.; Manica, J.; Benine, E.; M da Costa, E.; Dedavid, B. A.; Cusatis, C.; Huang, X. R.

    2009-09-13

    We characterized GaSb single crystals containing different dopants (Al, Cd and Te), grown by the Czochralski method, by x-ray topography and high angular resolution x-ray diffraction. Lang topography revealed dislocations parallel and perpendicular to the crystal's surface. Double-crystal GaSb 333 x-ray topography shows dislocations and vertical stripes than can be associated with circular growth bands. We compared our high-angular resolution x-ray diffraction measurements (rocking curves) with the findings predicted by the dynamical theory of x-ray diffraction. These measurements show that our GaSb single crystals have a relative variation in the lattice parameter ({Delta}d/d) on the order of 10{sup -5}. This means that they can be used as electronic devices (detectors, for example) and as x-ray monochromators.

  4. Synthesis and characterization of the ternary telluroargentate K4[Ag18Te11

    KAUST Repository

    Davaasuren, Bambar

    2014-10-19

    The ternary potassium telluroargentate(I), K4[Ag18Te11], was prepared by solvothermal synthesis in ethylenediamine at 160 °C. It crystallizes in the cubic space group Fm3¯ m (no. 225) with the cell parameter a = 18.6589(6) Å. The crystal structure can be described as a [Ag18Te11]4- three-dimensional anionic framework with the voids accommodating potassium cations. Chemical bonding analysis reveals polar covalent Ag-Te bonds and considerable Ag-Ag interactions, which support the complex anionic character of the structure. The compound is thermally stable up to 450 °C in an inert atmosphere.

  5. Synthesis and characterization of Taurine

    Directory of Open Access Journals (Sweden)

    B Bayarmaa

    2014-10-01

    Full Text Available Have been obtained 2-aminoethanesulfonic acid (taurine from ethanolamine, sulfuric acid and sodium sulfite during the synthesis in laboratory condition. The process involves two steps of reactions, the first was esterification of ethanolamine with sulfuric acid to produce the intermediate product of 2-aminoethyl ester which than was extended to the second step by sulfonation with sodium sulfite to produce 2-aminoethanesulfonic acid. Resulting product was analyzed using 1H-NMR, IR, FAB-MS analysis and examined purity characterizations of the synthesized products. DOI: http://dx.doi.org/10.5564/mjc.v14i0.200 Mongolian Journal of Chemistry 14 (40, 2013, p57-60

  6. YAP(Ce) crystal characterization with proton beam up to 60 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Randazzo, N. [Istituto Nazionale di Fisica Nucleare, Sezione di Catania (I), Via S. Sofia, 64-I-95123 Catania (Italy)], E-mail: nunzio.randazzo@ct.infn.it; Sipala, V.; Aiello, S. [Istituto Nazionale di Fisica Nucleare, Sezione di Catania (I), Via S. Sofia, 64-I-95123 Catania (Italy); Lo Presti, D. [Istituto Nazionale di Fisica Nucleare, Sezione di Catania (I), Via S. Sofia, 64-I-95123 Catania (Italy); Dipartimento di Fisica e Astronomia, Universita di Catania, Catania (Italy); Cirrone, G.A.P.; Cuttone, G.; Di Rosa, F. [Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali del Sud (Italy)

    2008-02-21

    A YAP(Ce) crystal was characterized with a proton beam up to 60 MeV. Tests were performed to investigate the possibility of using this detector as a proton calorimeter. The size of the crystal was chosen so that the proton energy is totally lost inside the medium. The authors propose to use the YAP(Ce) crystal in medical applications for proton therapy. In particular, in proton computed tomography (pCT) project it is necessary as a calorimeter in order to measure the proton residual energy after the phantom. Energy resolution, linearity, and light yield were measured in the Laboratori Nazionali del Sud with the CATANA proton beam [ (http://www.lns.infn.it/CATANA/CATANA)] and the results are shown in this paper. The crystal shows a good resolution (3% at 60 MeV proton beam) and it shows good linearity for different proton beam energies (1% at 30-60 MeV energy range). The crystal performances confirm that the YAP(Ce) crystal represents a good solution for these kinds of application.

  7. YAP(Ce) crystal characterization with proton beam up to 60 MeV

    International Nuclear Information System (INIS)

    Randazzo, N.; Sipala, V.; Aiello, S.; Lo Presti, D.; Cirrone, G.A.P.; Cuttone, G.; Di Rosa, F.

    2008-01-01

    A YAP(Ce) crystal was characterized with a proton beam up to 60 MeV. Tests were performed to investigate the possibility of using this detector as a proton calorimeter. The size of the crystal was chosen so that the proton energy is totally lost inside the medium. The authors propose to use the YAP(Ce) crystal in medical applications for proton therapy. In particular, in proton computed tomography (pCT) project it is necessary as a calorimeter in order to measure the proton residual energy after the phantom. Energy resolution, linearity, and light yield were measured in the Laboratori Nazionali del Sud with the CATANA proton beam [ (http://www.lns.infn.it/CATANA/CATANA)] and the results are shown in this paper. The crystal shows a good resolution (3% at 60 MeV proton beam) and it shows good linearity for different proton beam energies (1% at 30-60 MeV energy range). The crystal performances confirm that the YAP(Ce) crystal represents a good solution for these kinds of application

  8. YAP(Ce) crystal characterization with proton beam up to 60 MeV

    Science.gov (United States)

    Randazzo, N.; Sipala, V.; Aiello, S.; Lo Presti, D.; Cirrone, G. A. P.; Cuttone, G.; Di Rosa, F.

    2008-02-01

    A YAP(Ce) crystal was characterized with a proton beam up to 60 MeV. Tests were performed to investigate the possibility of using this detector as a proton calorimeter. The size of the crystal was chosen so that the proton energy is totally lost inside the medium. The authors propose to use the YAP(Ce) crystal in medical applications for proton therapy. In particular, in proton computed tomography (pCT) project it is necessary as a calorimeter in order to measure the proton residual energy after the phantom. Energy resolution, linearity, and light yield were measured in the Laboratori Nazionali del Sud with the CATANA proton beam [ http://www.lns.infn.it/CATANA/CATANA] and the results are shown in this paper. The crystal shows a good resolution (3% at 60 MeV proton beam) and it shows good linearity for different proton beam energies (1% at 30-60 MeV energy range). The crystal performances confirm that the YAP(Ce) crystal represents a good solution for these kinds of application.

  9. Growth and characterization of KDP crystals doped with L-aspartic acid.

    Science.gov (United States)

    Krishnamurthy, R; Rajasekaran, R; Samuel, Bincy Susan

    2013-03-01

    Potassium Dihydrogen Phosphate (KDP) doped with L-aspartic acid has been grown by solvent slow evaporation technique from a mixture of aqueous solution of KDP and 0.7% of L-aspartic acid at room temperature. The grown crystals were characterized by powder X-ray diffraction, UV-visible, FTIR analysis. The doping of aspartic acid was confirmed by FTIR spectrum. The Nonlinear optical property (SHG) of L-aspartic acid doped KDP has been confirmed. Microhardness studies were carried out on the grown crystal. Copyright © 2012 Elsevier B.V. All rights reserved.

  10. The crystal structure of escherichia coli MoaB suggests a probable role in molybdenum cofactor synthesis

    International Nuclear Information System (INIS)

    Sanishvili, R.; Beasley, S.; Skarina, T; Glesne, D; Joachimiak, A; Edwards, A; Savchenko, A.; Univ. Health Network; Univ. of Toronto

    2004-01-01

    The crystal structure of Escherichia coli MoaB was determined by multiwavelength anomalous diffraction phasing and refined at 1.6 Angstrom resolution. The molecule displayed a modified Rossman fold. MoaB is assembled into a hexamer composed of two trimers. The monomers have high structural similarity with two proteins, MogA and MoeA, from the molybdenum cofactor synthesis pathway in E. Coli, as well as with domains of mammalian gephyrin and plant Cnx1, which are also involved in molybdopterin synthesis. Structural comparison between these proteins and the amino acid conservation patterns revealed a putative active site in MoaB. The structural analysis of this site allowed to advance several hypothesis which can be tested in further studies

  11. Synthesis and characterization of a nanostructured matrix hydroxyapatite ceramic bone reconstruction

    International Nuclear Information System (INIS)

    Correa, P.; Camargo, N.H.A.; Silva, D.F.

    2012-01-01

    The nanostructured ceramics have been shown promise as biomaterials for bone reconstruction. Among calcium phosphates, hydroxyapatite Ca/P ratio = 1.67 mol stands out because of its crystallographic similarity with the mineral bone phase and biocompatibility. This work was based on synthesis and characterization of a nanostructured hydroxyapatite for use in reconstituting bone tissue. The synthesis method for obtaining the bioceramic powder occurred at process of dissolution/precipitation, involving CaO solid/liquid and phosphoric acid required for forming the composition of Ca/P = 1.67 mole. The material recovered from the synthesis was calcined at 900 ° C/2h, providing the hydroxyapatite powder nanometer. This was subjected to mechanical fragmentation process in mill attritor, providing a hydroxyapatite with modified surface morphology. The results presented relate to morphological characterization studies (SEM), mineralogical (XRD), chemical (FTIR) and particle size distribution, using the laser particle size analysis method. Such results showed the formation of hydroxyapatite phase and morphology satisfactory for use in reconstituting bone tissue

  12. Lanthanide phosphonates: Synthesis, thermal stability and magnetic characterization

    Energy Technology Data Exchange (ETDEWEB)

    Amghouz, Z., E-mail: amghouz.uo@uniovi.es [Departamentos de Quimica Fisica y Analitica y Quimica Organica e Inorganica, Universidad de Oviedo - CINN, 33006 Oviedo (Spain); Garcia, J.R.; Garcia-Granda, S. [Departamentos de Quimica Fisica y Analitica y Quimica Organica e Inorganica, Universidad de Oviedo - CINN, 33006 Oviedo (Spain); Clearfield, A. [Department of Chemistry, Texas A and M University, College Station, TX 77842-3012 (United States); Rodriguez Fernandez, J.; Pedro, I. de [CITIMAC, Facultad de Ciencias, Universidad de Cantabria, 39005 Santander (Spain); Blanco, J.A. [Departamento de Fisica, Universidad de Oviedo, 33007 Oviedo (Spain)

    2012-09-25

    Highlights: Black-Right-Pointing-Pointer Report of the complete series of lanthanide 1,4-phenylbis(phosphonate). Black-Right-Pointing-Pointer Synthesis under conventional hydrothermal synthesis or microwave-assisted hydrothermal synthesis. Black-Right-Pointing-Pointer Cation size is the key factor for the structural and particles size variations. Black-Right-Pointing-Pointer Thermal behaviour is characterized by unusual very high thermal stability. - Abstract: Series of novel organic-inorganic hybrids materials based on trivalent lanthanides (Ln = Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu) and 1,4-phenylbis(phosphonate) obtained under hydrothermal conditions either by oven heat or microwave irradiation. The anhydrous compounds containing La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, and Ho, are isostructural. However, the compounds based on Y, Er, Tm, Yb, and Lu are hydrated and their structures have not yet been solved. The series of compounds are characterized by PXRD, TEM, SEM-EDX and thermal analyses (TG-MS and DSC). TEM study show a variable particles size with a minimum mean-particle size of ca. 30 nm. These compounds exhibit unusual very high thermal stability. The size of particles and the thermal stability are depending on lanthanide(III) cation features. All the investigated materials show paramagnetic behaviour. The magnetic susceptibility data follow a Curie-Weiss laws with paramagnetic effective moments in good agreement with those expected for Ln{sup 3+} free ions.

  13. Bis[(2,3,4-Trimethoxy-Benzylidenepropylideneamino)Phenyl] Ether: Synthesis, characterization and crystal structure

    Czech Academy of Sciences Publication Activity Database

    Khalaji, A.D.; Fejfarová, Karla; Dušek, Michal

    2012-01-01

    Roč. 42, č. 3 (2012), s. 263-266 ISSN 1074-1542 Grant - others:AV ČR(CZ) AP0701 Program:Akademická prémie - Praemium Academiae Institutional research plan: CEZ:AV0Z10100521 Keywords : Shiff bases * crystal structure * X-ray diffraction * Jana2006 Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 0.513, year: 2012

  14. Synthesis and structural characterization of luminescent inorganic materials of the type CS2NaErBr6 and CS2NaHoBr6

    International Nuclear Information System (INIS)

    Poblete, V.H.; Fack, G.

    2001-01-01

    The synthesis and structural characterization is described of two luminescent materials, with technological [1] and spectroscopic [2] interest, whose crystallographic charts have not been published in the literature. The synthesis of both systems: Cs 2 NaErBr 6 and CS 2 NaHoBr 6 , was done using solid state reactions in a controlled environment. The thermal analyses DTA/TGA, applied with a temperature gradient of 10 o C/min., established crystallization ranges of 490,4 o C to 545,4 o C, for the elpasolite CS 2 NaHoBr 6 and 501 o C to 556 o C, for the structure CS 2 NaErBr 6 .. The heat vacuum treatments were carried out at 505 o C and 526 o C respectively, obtaining optimum crystallization. The structural characterization was performed with powdered X-ray diffraction (XRD). The range between 12 o and 80 o (2θ), was analyzed for 3352 points, measured steps of 0.02 o (2θ using the Rietveld profile refining program. The following crystallographic parameters were established: a 0 = 11,279(1), and 11,293(4) Angstroms, for the two structures analyzed, respectively. The relationship R exp wp in both cases is highly accurate for the 32 test lines that were analyzed. The structures present cubic closed packing Cs 1+ 3 Cl 1- , with Ho 3+ and Er 3+ atoms, filling the octahedral holes. The test data obtained will be very useful for completing the mass of experimental data needed to develop the design engineering, with specific applications for luminescent devices

  15. Introduction to crystal growth and characterization

    CERN Document Server

    Benz, Klaus-Werner

    2014-01-01

    This new textbook provides for the first time a comprehensive treatment of the basics of contemporary crystallography and crystal growth in a single volume. The reader will be familiarized with the concepts for the description of morphological and structural symmetry of crystals. The architecture of crystal structures of selected inorganic and molecular crystals is illustrated. The main crystallographic databases as data sources of crystal structures are described. Nucleation processes, their kinetics and main growth mechanism will be introduced in fundamentals of crystal growth. Some phase d

  16. Growth and characterization of single-crystal CVD diamond for radiation detection applications

    International Nuclear Information System (INIS)

    Tranchant, N.

    2008-01-01

    This work aimed at the study of the synthesis of single crystal diamond using the Microwave enhanced Chemical Vapour Deposition technique (MPCVD). The work enabled the development and optimisation of the growth conditions, from the study of the crystalline quality, of the material purity, and of its electronic properties. The assessment of the transport properties was the most determinant: the use of the time of flight (TOF) technique has enabled the measurement of the carrier mobilities and of their kinetic properties as a function of the temperature. When coupled with collected charge efficiency measurements, the work led to remarkable carrier mobility values obtained in the synthesised crystals (3000 cm 2 .V-1.s -1 ). Prepared samples were mounted as detection devices and used successfully in real conditions for the monitoring of ultra-fast pulses, as well as for neutron fluency monitoring, and for medical dosimeters for radiotherapy applications. (author)

  17. Crystal growth and characterization of new semiorganic nonlinear optical single crystals

    Energy Technology Data Exchange (ETDEWEB)

    Kulshrestha, Shobha, E-mail: shobha011986@gmail.com; Shrivastava, A. K., E-mail: ashwaniaks@rediffmail.com [School of Studies in Physics, Jiwaji University Gwalior (M.P.) – 474 011 (India)

    2016-05-06

    An organic material of a L-histidine monohydrochloride single crystal was grown in a distilled water solution using the slow evaporation method at 40–45°C. The grown crystal was transparent and colourless, with a size of about 20 × 9 × 5 mm{sup 3}, obtained within a period of 21 days. The solubility of grown crystals have found out at various temperatures. The UV-visible transmittance studies show that the grown crystals have wide optical transparency in the entire visible region It is observed that the crystal has transparency window from 255nm to 700nm and its energy gap (Eg) found to be is 3.1eV. The grown crystal was subjected to powder X-ray diffraction analysis, confirming that the orthorhombic crystalline nature of the crystal. To identify the surface morphology, the as grown crystal was subjected to FE-SEM technique. The chemical composition of the grown crystal was estimated by Energy dispersive X-ray analysis. The optical behaviour of the grown crystal was analyzed by PL study.

  18. Synthesis, Properties Characterization and Applications of Various Organobismuth Compounds

    Directory of Open Access Journals (Sweden)

    Jingfei Luan

    2011-05-01

    Full Text Available Organobismuth chemistry was emphasized in this review article due to the low price, low toxicity and low radioactivity characteristics of bismuth. As an environmentally-friendly class of organometallic compounds, different types of organobismuth compounds have been used in organic synthesis, catalysis, materials, etc. The synthesis and property characterization of many organobismuth compounds had been summarized. This review article also presented a survey of various applications of organobismuth compounds in organic transformations, as reagents or catalysts. The reactivity, reaction pathways and mechanisms of reactions with organobismuths were discussed. Less common and limiting aspects of organobismuth compounds were also briefly mentioned.

  19. SYNTHESIS AND CHARACTERIZATION OF NEW HALOGENATED CURCUMINOIDS

    Directory of Open Access Journals (Sweden)

    Eugenio Torres

    2013-12-01

    Full Text Available In this work a novel procedure of synthesis of compounds analogues to curcumin with halogens atoms in its structure is described, which can increase its solubility and biological activity. Four halogenated curcuminoids were obtained with great pharmacological interest, none of them reported in literature before. Synthesis was carried out by means of the aldol condensation assisted by microwaves of halogenated aromatic aldehydes and acetylacetona, using morpholine as basic catalyst, in absence of solvent, and the reaction just needed 1 min. The products were purified by treatment of the reaction mixture with methanol under ultrasound irradiation, followed by chromatographic column. All obtained compounds were characterized by infrared spectroscopy, nuclear magnetic resonance, quantitative elementary analysis and high resolution mass spectrometry. The RMN-1H data demonstrate in all structures of synthesized curcuminoids the enol form is the most favored.

  20. Dispersed-nanoparticle loading synthesis for monodisperse Au-titania composite particles and their crystallization for highly active UV and visible photocatalysts.

    Science.gov (United States)

    Sakamoto, Takeshi; Nagao, Daisuke; Noba, Masahiro; Ishii, Haruyuki; Konno, Mikio

    2014-06-24

    Submicrometer-sized amorphous titania spheres incorporating Au nanoparticles (NPs) were prepared in a one-pot synthesis consisting of a sol-gel reaction of titanium(IV) isopropoxide in the presence of chloroauric acid and a successive reduction with sodium borohydride in a mixed solvent of ethanol/acetonitrile. The synthesis was allowed to prepare monodisperse titania spheres that homogeneously incorporated Au NPs with sizes of ca. 7 nm. The Au NP-loaded titania spheres underwent different crystallization processes, including 500 °C calcination in air, high-temperature hydrothermal treatment (HHT), and/or low-temperature hydrothermal treatment (LHT). Photocatalytic experiments were conducted with the Au NP-loaded crystalline titania spheres under irradiation of UV and visible light. A combined process of LHT at 80 °C followed by calcination at 500 °C could effectively crystallize titania spheres maintaining the dispersion state of Au NPs, which led to photocatalytic activity higher than that of commercial P25 under UV irradiation. Under visible light irradiation, the Au NP-titania spheres prepared with a crystallization process of LHT at 80 °C for 6 h showed photocatalytic activity much higher than a commercial product of visible light photocatalyst. Structure analysis of the visible light photocatalysts indicates the importance of prevention of the Au NPs aggregation in the crystallization processes for enhancement of photocatalytic activity.

  1. Characterization of a polychromatic neutron beam diffracted by pyrolytic graphite crystals

    CERN Document Server

    Byun, S H; Choi, H D

    2002-01-01

    The beam spectrum for polychromatic neutrons diffracted by pyrolytic graphite crystals was characterized. The theoretical beam spectrum was obtained using the diffraction model for a mosaic crystal. The lattice vibration effects were included in the calculation using the reported vibration amplitude of the crystal and the measured time-of-flight spectra in the thermal region. The calculated beam spectrum was compared with the results obtained in the absence of thermal motion. The lattice vibration effects became more important for the higher diffraction orders and a large decrease in the neutron flux induced by the vibrations was identified in the epithermal region. The validity of the beam spectrum was estimated by comparing with the effective quantities determined from prompt gamma-ray measurements and Cd-ratios measured both for 1/nu and non-1/nu nuclides.

  2. Barium titanate inverted opals-synthesis, characterization, and optical properties

    Energy Technology Data Exchange (ETDEWEB)

    Soten, I.; Miguez, H.; Yang, S.M.; Petrov, S.; Coombs, N.; Tetreault, N.; Ozin, G.A. [Toronto Univ., ON (Canada). Dept. of Chemistry; Matsuura, N.; Ruda, H.E. [Toronto Univ., ON (Canada). Dept. of Metallurgy and Materials Science

    2002-01-01

    The engineering of cubic or tetragonal polymorphs of nanocrystalline barium titanate inverted opals has been achieved by thermally induced transformations. Optical characterization demonstrated photonic crystal behavior of the opals. The tuning of the ferroelectric-paraelectric transition around the Curie temperature is shown in this paper. (orig.)

  3. Synthesis and characterization of thermally oxidized ZnO films

    Indian Academy of Sciences (India)

    Administrator

    Synthesis and characterization of thermally oxidized ZnO films. A P RAMBU1,* and N IFTIMIE2 .... R. −. Δ. = = (1) where Ra is the sensor resistance in the air and Rg is the .... ple, Aida and coworkers (2006) reported that the total oxidation is ...

  4. Synthesis, characterization and crystal structure of a 2-(diethylaminomethylindole ligated dimethylaluminium complex

    Directory of Open Access Journals (Sweden)

    Logan E. Shephard

    2015-10-01

    Full Text Available The title compound, [Al(CH32(C13H17N2] (systematic name; {2-[(diethylaminomethyl]indol-1-yl-κ2N,N′}dimethylaluminium, was prepared by methane elimination from the reaction of 2-(diethylaminomethylindole and trimethylaluminium. The complex crystallizes readily from a concentrated toluene solution in high yield. The asymmetric unit contains two crystallographically independent molecules. Each molecule has a four-coordinate aluminium atom that has pseudo-tetrahedral geometry. C—H...π interactions link the independent molecules into chains extending along the b-axis direction.

  5. Synthesis, crystal structure refinement, and nonlinear-optical properties of CaB3O5(OH): Comparative crystal chemistry of calcium triborates

    International Nuclear Information System (INIS)

    Yamnova, N. A.; Aksenov, S. M.; Stefanovich, S. Yu.; Volkov, A. S.; Dimitrova, O. V.

    2015-01-01

    Calcium triborate CaB 3 O5(OH) obtained by hydrothermal synthesis in the Ca(OH) 2 –H 3 BO 3 –Na 2 CO 3 –KCl system is studied by single-crystal X-ray diffraction. The parameters of the orthorhombic unit cell are as follows: a = 13.490(1), b = 6.9576(3), and c = 4.3930(2) Å; V = 412.32(3) Å 3 and space group Pna2 1 . The structure is refined in the anisotropic approximation of the atomic displacement parameters to R = 4.28% using 972 vertical bar F vertical bar > 4σ(F). It is confirmed that the crystal structure of Ca triborate CaB 3 O 5 (OH) is identical to that described earlier. The hydrogen atom is localized. An SHG signal stronger than that of the quartz standard is registered. The phase transition of calcium triborate into calciborite is found on heating. The comparative crystal-chemical analysis of a series of borates with the general chemical formula 2CaO · 3B 2 O 3 · nH 2 O (n = 0–13) with the constant CaO: B 2 O 3 = 2: 3 ratio and variable content of water is performed

  6. Gadolinium (III) 2-benzoyl-1,1,3,3-tetracyanopropenide diacetate. Synthesis and crystal structure

    Energy Technology Data Exchange (ETDEWEB)

    Karpov, Sergey V.; Kayukov, Yakov S.; Grigor' ev, Arthur A. [Department of Chemistry and Pharmaceutics, I.N. Ul' yanov Chuvash State University, Cheboksary (Russian Federation); Tafeenko, Victor A. [Department of Chemistry, Lomonosov Moscow State University (Russian Federation)

    2018-02-15

    2-Acyl-1,1,3,3-tetracyanopropenides (ATCN) is a stable organic salts, containing the carbonyl group in addition to the tetracyanoallyl (TCA) fragment in the anion. TCA anions are known as bridging ligands with variable denticity with potential application in organic electronics and as a ionic liquids components. In this communication we reporting the synthesis and crystal structure of gadolinium(III) 2-benzoyl-1,1,3,3-tetracyanopropenide diacetate - the first lanthanide ATCN. (copyright 2018 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  7. Selective synthesis of FAU-type zeolites

    Science.gov (United States)

    Garcia, Gustavo; Cabrera, Saúl; Hedlund, Jonas; Mouzon, Johanne

    2018-05-01

    In the present work, parameters influencing the selectivity of the synthesis of FAU-zeolites from diatomite were studied. The final products after varying synthesis time were characterized by scanning electron microscopy, energy dispersive spectroscopy, X-ray diffraction and gas adsorption. It was found that high concentrations of NaCl could completely inhibit the formation of zeolite P, which otherwise usually forms as soon as maximum FAU crystallinity is reached. In the presence of NaCl, the FAU crystals were stable for extended time after completed crystallization of FAU before formation of sodalite. It was also found that addition of NaCl barely changed the crystallization kinetics of FAU zeolite and only reduced the final FAU particle size and SiO2/Al2O3 ratio slightly. Other salts containing either Na or Cl were also investigated. Our results suggest that there is a synergistic effect between Na+ and Cl-. This is attributed to the formation of (Na4Cl)3+ clusters that stabilize the sodalite cages. This new finding may be used to increase the selectivity of syntheses leading to FAU-zeolites and avoid the formation of undesirable by-products, especially if impure natural sources of aluminosilica are used.

  8. Synthesis of hexavalent molybdenum formo- and aceto-hydroxamates and deferoxamine via liquid-liquid metal partitioning

    Energy Technology Data Exchange (ETDEWEB)

    Breshears, Andrew T.; Brown, M. Alex; Bloom, Ira; Barnes, Charles L.; Gelis, Artem V.

    2018-03-01

    We report a new method of crystal growth and synthesis based on liquid-liquid partitioning that allows for isolation and in-depth characterization of molybdenyl bis(formohydroxamate), Mo-FHA, molybdenyl bis(acetohydroxamate), Mo-AHA, and molybdenyl deferoxamine, Mo-DFO, for the first time. This novel approach affords shorter crystal growth time (hourly timeframe) without sacrificing crystal size or integrity when other methods of crystallization were unsuccessful. All three Mo complexes are characterized in solution via FTIR, NMR, UV-vis, and EXAFS spectroscopy. Mo-AHA and Mo-FHA structures are resolved by single crystal X-ray diffraction. Using the molybdenyl hydroxamate structural information, the speciation of Mo in a siderophore complex (Mo-DFO) is determined via complimentary spectroscopic methods and confirmed by DFT calculations. ESI-MS verifies that a complex of 1:1 molybdenum to deferoxamine is present in solution. Additionally, the Mo solution speciation in the precursor organic phase, MoO2(NO3)2HEH[EHP]2 (where HEH[EHP] is 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester), is characterized by FTIR and EXAFS spectroscopy as well as DFT calculations.

  9. Synthesis and crystal structure of two lead (II) complexes with 1,10-phenanthroline ligand

    International Nuclear Information System (INIS)

    Olivera, Fiorella L.; Santillan, Guillermo A.

    2012-01-01

    Two coordination complexes have been synthesized by the reaction of lead nitrate (II) with 1,10-phenanthroline in methanol/water. The crystals of these complexes were obtained by using the diffusion method and structurally characterized by X-ray single crystal diffraction. Both complexes crystallized in the monoclinic space group P2 1 /c. The analysis by crystal X-ray diffraction reveals that in both complexes the coordination around the lead (II) ion is a distorted octahedral structure where the ion is bonded to the heterocyclic nitrogen atoms of chelating ligand 1,10-phenanthroline, three oxygen atoms of three nitrate groups and one oxygen from the water molecule. The difference between the complexes lies in the way of nitrate ion in presence of carboxylic acid aromatics. In addition, the crystal structure of complexes can be regarded as a 3D coordination polymer through Pb-O weak interactions, hydrogen bonds and π-π stacking interactions. (author).

  10. Use of Vegetable Waste Extracts for Controlling Microstructure of CuO Nanoparticles: Green Synthesis, Characterization, and Photocatalytic Applications

    Directory of Open Access Journals (Sweden)

    Hameed Ullah

    2017-01-01

    Full Text Available Chemical syntheses involve either hazardous reactants or byproducts which adversely affect the environment. It is, therefore, desirable to develop synthesis processes which either do not involve hazardous reactants or consume all the reactants giving no byproducts. We have synthesized CuO nanoparticles (NPs adhering to some of the principles of green chemistry. The CuO NPs have been synthesized exploiting extracts of vegetable wastes, that is, Cauliflower waste and Potatoes and Peas peels. The extracts were aimed to work as capping agents to get control over the microstructure and morphology of the resulting CuO NPs. The green synthesized CuO NPs were characterized to explore the microstructure, morphology, optical bandgaps, and photocatalytic performances. XRD revealed that the CuO NPs of all the samples crystallized in a single crystal system, that is, monoclinic. However, the morphologies and the optical bandgaps energies varied as a function of the extract of vegetable waste. Similarly, the CuO NPs obtained through different extracts have shown different photocatalytic activities. The CuO NPs produced with extract of Cauliflower have shown high degradation of MB (96.28% compared to obtained with Potatoes peels (87.37% and Peas peels (79.11%.

  11. Ferromagnetism in CVT grown tungsten diselenide single crystals with nickel doping

    Science.gov (United States)

    Habib, Muhammad; Muhammad, Zahir; Khan, Rashid; Wu, Chuanqiang; Rehman, Zia ur; Zhou, Yu; Liu, Hengjie; Song, Li

    2018-03-01

    Two dimensional (2D) single crystal layered transition materials have had extensive consideration owing to their interesting magnetic properties, originating from their lattices and strong spin-orbit coupling, which make them of vital importance for spintronic applications. Herein, we present synthesis of a highly crystalline tungsten diselenide layered single crystal grown by chemical vapor transport technique and doped with nickel (Ni) to tailor its magnetic properties. The pristine WSe2 single crystal and Ni-doped crystal were characterized and analyzed for magnetic properties using both experimental and computational aspects. It was found that the magnetic behavior of the 2D layered WSe2 crystal changed from diamagnetic to ferromagnetic after Ni-doping at all tested temperatures. Moreover, first principle density functional theory (DFT) calculations further confirmed the origin of room temperature ferromagnetism of Ni-doped WSe2, where the d-orbitals of the doped Ni atom promoted the spin moment and thus largely contributed to the magnetism change in the 2D layered material.

  12. Accuracy synthesis of T-shaped exit fixed mechanism in a double-crystal monochromator

    International Nuclear Information System (INIS)

    Wang Fengqin; Cao Chongzhen; Wang Jidai; Li Yushan; Gao Xueguan

    2007-01-01

    It is a key performance requirement for a double-crystal monochromator that the exit is fixed, and in order to improve the height accuracy of the exit in T-shaped exit fixed mechanism, the expression between the height of the exit and various original errors was put forward using geometrical analysis method. According to the independent action principle of original errors, accuracy synthesis of T-shaped exit fixed mechanism was studied by using the equal accuracy method, and the tolerance ranges of original errors were obtained. How to calculate the tolerance ranges of original errors was explained by giving an example. (authors)

  13. The iron member of the CPO-27 coordination polymer series: Synthesis, characterization, and intriguing redox properties

    DEFF Research Database (Denmark)

    Märcz, Matthias; Johnsen, Rune; Dietzel, Pascal D.C.

    2012-01-01

    The microporous coordination polymer CPO-27-Fe was synthesized from iron salts and 2,5-dihydroxyterephthalic acid by microwave assisted solvothermal synthesis. The crystal structures of the as-synthesized compounds were determined by Rietveld refinement from powder X-ray diffraction data using...

  14. Transition metal borides. Synthesis, characterization and superconducting properties

    International Nuclear Information System (INIS)

    Kayhan, Mehmet

    2013-01-01

    A systematic study was done on the synthesis and superconducting properties of metal rich transition metal borides. Five different binary systems were investigated including the boride systems of niobium, tantalum, molybdenum, tungsten and rhenium. High temperature solid state methods were used in order to synthesize samples of different transition metal borides of the composition M 2 B, MB, M 3 B 2 , MB 2 , and M 2 B 4 . The reactions were carried out in three different furnaces with different sample containers: the electric arc (copper crucible), the high frequency induction furnace (boron nitride, tantalum or glassy carbon crucibles), and the conventional tube furnace (sealed evacuated quartz ampoules). The products obtained were characterized with X-ray powder diffractometry, scanning electron microscopy and energy-dispersive X-ray spectroscopy. Phase analyses and crystal structure refinements using the Rietveld method and based on structure models known from literature were performed. A neutron diffraction measurement was done for W 2 B 4 to allow for a complete crystal structure determination, because of the presence of a heavy element like tungsten and a light element like boron that made it difficult to determine the accurate determination of the boron atom positions and occupancies from X-ray data. A new structure model for W 2 B 4 was proposed. Magnetic measurements in a SQUID magnetometer down to temperatures as low as 1.8 K were performed to several of the products in order to see if the transition metal borides become superconducting at low temperatures, and the results were compared with data from literature. Superconducting properties were found for the following compounds: NbB 2 (T C = 3.5 K), β-MoB (T C = 2.4 K), β-WB (T C = 2.0 K), α-WB (T C = 4.3 K), W 2 B 4 (T C = 5.4 K), Re 7 B 3 (T C = 2.4 K). A relationship between the superconducting properties and the compositional and structural features was discussed for metal diborides. Also it was

  15. Synthesis and Characterization of Chemically Etched Nanostructured Silicon

    KAUST Repository

    Mughal, Asad Jahangir

    2012-05-01

    Silicon is an essential element in today’s modern world. Nanostructured Si is a more recently studied variant, which has currently garnered much attention. When its spatial dimensions are confined below a certain limit, its optical properties change dramatically. It transforms from an indirect bandgap material that does not absorb or emit light efficiently into one which can emit visible light at room temperatures. Although much work has been conducted in understanding the properties of nanostructured Si, in particular porous Si surfaces, a clear understanding of the origin of photoluminescence has not yet been produced. Typical synthesis approaches used to produce nanostructured Si, in particular porous Si and nanocrystalline Si have involved complex preparations used at high temperatures, pressures, or currents. The purpose of this thesis is to develop an easier synthesis approach to produce nanostructured Si as well as arrive at a clearer understanding of the origin of photoluminescence in these systems. We used a simple chemical etching technique followed by sonication to produce nanostructured Si suspensions. The etching process involved producing pores on the surface of a Si substrate in a solution containing hydrofluoric acid and an oxidant. Nanocrystalline Si as well as nanoscale amorphous porous Si suspensions were successfully synthesized using this process. We probed into the phase, composition, and origin of photoluminescence in these materials, through the use of several characterization techniques. TEM and SEM were used to determine morphology and phase. FT-IR and XPS were employed to study chemical compositions, and steady state and time resolved optical spectroscopy techniques were applied to resolve their photoluminescent properties. Our work has revealed that the type of oxidant utilized during etching had a significant impact on the final product. When using nitric acid as the oxidant, we formed nanocrystalline Si suspensions composed of

  16. Synthesis and characterization of amorphous cellulose from triacetate of cellulose

    International Nuclear Information System (INIS)

    Vega-Baudrit, Jose; Sibaja, Maria; Nikolaeva, Svetlana; Rivera A, Andrea

    2014-01-01

    It was carried-out a study for the synthesis and characterization of amorphous cellulose starting from cellulose triacetate. X-rays diffraction was used in order to obtain the cellulose crystallinity degree, also infrared spectroscopy FTIR was used. (author)

  17. Manufacturing and characterization of bent silicon crystals for studies of coherent interactions with negatively charged particles beams

    Energy Technology Data Exchange (ETDEWEB)

    Germogli, G.; Mazzolari, A.; Bandiera, L.; Bagli, E.; Guidi, V.

    2015-07-15

    Efficient steering of GeV-energy negatively charged particle beams was demonstrated to be possible with a new generation of thin bent silicon crystals. Suitable crystals were produced at the Sensor Semiconductor Laboratory of Ferrara starting from Silicon On Insulator wafers, adopting proper revisitation of silicon micromachining techniques such as Low Pressure Chemical Vapor Deposition, photolithography and anisotropic chemical etching. Mechanical holders, which allow to properly bend the crystal and to reduce unwanted torsions, were employed. Crystallographic directions and crystal holder design were optimized in order to excite quasi-mosaic effect along (1 1 1) planes. Prior to exposing the crystal to particle beams, a full set of characterizations were performed. Infrared interferometry was used to measure crystal thickness with high accuracy. White-light interferometry was employed to characterize surface deformational state and its torsion. High-resolution X-rays diffraction was used to precisely measure crystal bending angle along the beam. Manufactured crystals were installed and tested at the MAMI MAinz MIcrotron to steer sub-GeV electrons, and at SLAC to deflect an electron beam in the 1 to 10 GeV energy range.

  18. On the Synthesis and Optical Characterization of Zero-Dimensional-Networked Perovskites

    KAUST Repository

    Almutlaq, Jawaher

    2017-04-26

    The three-dimensional perovskites are known for their wide range of interesting properties including spectral tunability, charge carrier mobility, solution-based synthesis and many others. Such properties make them good candidates for photovoltaics and photodetectors. Low-dimensional perovskites, on the other hand, are good as light emitters due to the quantum confinement originating from their nanoparticle size. Another class of low-dimensional perovskites, also called low-dimensional-networked perovskites (L-DN), is recently reemerging. Those interesting materials combine the advantages of the nanocrystals and the stability of the bulk. For example, zero-dimensional-networked perovskite (0-DN), a special class of perovskites and the focus of this work, consists of building blocks of isolated lead-halide octahedra that could be synthesized into mm-size single crystal without losing their confinement. This thesis focuses on the synthesis and investigation of the optical properties of the 0-DN perovskites through experimental, theoretical and computational tools. The recent discovery of the retrograde solubility of the perovskites family (ABX3), the basis of the inverse temperature crystallization (ITC), inspired the reinvestigation of the low-dimensional-networked perovskites. The results of the optical characterization showed that the absorption and the corresponding PL spectra were successfully tuned to cover the visible spectrum from 410 nm for Cs4PbCl6, to 520 nm and 700 m for Cs4PbBr6 and Cs4PbI6, respectively. Interestingly, the exciton binding energies (Eb) of the 0-DNs were found to be in the order of few hundred meV(s), at least five times larger than their three-dimensional counterpart. Such high Eb is coupled with a few nanoseconds lifetime and ultimately yielded a high photoluminesce quantum yield (PLQY). In fact, the PLQY of Cs4PbBr6 powder showed a record of 45%, setting a new benchmark for solid-state luminescent perovskites. Computational methods

  19. Characterization structural and morphology ZSM-5 zeolite by hydrothermal synthesis

    International Nuclear Information System (INIS)

    Silva, V.J.; Crispim, A.C.; Queiroz, M.B.; Laborde, H.M.; Rodrigues, M.G.F.; Menezes, R.R.

    2009-01-01

    Solid acids are catalytic materials commonly used in the chemical industry. Among these zeolites are the most important business processes including water treatment, gas separation, and cracking long hydrocarbon chains to produce high octane gasoline. Its synthesis, characterization and applications have been widely studied. The objective this study was to synthesize the ZSM-5 zeolite for future use in separation processes and catalysis. The zeolite ZSM-5 was prepared by hydrothermal synthesis at 170°C, using silica, deionized water and the director of structures (TPABr - tetrapropylammonium bromide). The materials were characterized by X ray diffraction (XRD), scanning electron microscopy (SEM) and semiquantitative chemical analysis by X ray fluorescence (XRF). According to the XRD was possible to observe the formation of ZSM-5 zeolite, with peaks intense and well defined. The SEM showed the formation of individual particles, clean, rounded shapes. (author)

  20. Polymer Brushes: Synthesis, Characterization, Applications

    Science.gov (United States)

    Advincula, Rigoberto C.; Brittain, William J.; Caster, Kenneth C.; Rühe, Jürgen

    2004-09-01

    Materials scientists, polymer chemists, surface physicists and materials engineers will find this book a complete and detailed treatise on the field of polymer brushes, their synthesis, characterization and manifold applications. In a first section, the various synthetic pathways and different surface materials are introduced and explained, followed by a second section covering important aspects of characterization and analysis in both flat surfaces and particles. These specific surface initiated polymerization (SIP) systems such as linear polymers, homopolymers, block copolymers, and hyperbranched polymers are unique compared to previously reported systems by chemisorption or physisorption. They have found their way in both large-scale and miniature applications of polymer brushes, which is covered in the last section. Such 'hairy' surfaces offer fascinating opportunities for addressing numerous problems of both academic and, in particular, industrial interest: high-quality, functional or protective coatings, composite materials, surface engineered particles, metal-organic interfaces, biological applications, micro-patterning, colloids, nanoparticles, functional devices, and many more. It is the desire of the authors that this book will be of benefit to readers who want to "brush-up on polymers".

  1. Mineralizer-assisted high-pressure high-temperature synthesis and characterization of novel phosphorus nitride imides and luminescent alkaline earth metal (oxo)nitridophosphates

    International Nuclear Information System (INIS)

    Marchuk, Alexey

    2016-01-01

    The main objectives of this thesis were the synthesis, identification and structural characterization of new alkaline earth metal (oxo)nitridophopshates and phosphorus nitrides. Furthermore, luminescence properties of the resulting materials should be investigated and a connection between these properties and the respective structures should be established. For this purpose, a range of synthesis strategies was employed, including conventional solid-state syntheses in silica ampoules and high-pressure high-temperature syntheses using the multianvil technique. The emphasis of the synthetic part of this thesis lies on the development of new synthetic strategies in order to increase crystallinity of alkaline earth metal (oxo)nitridophosphates and thus accelerate their structure determination. This involves the selection of a suitable mineralizer and the investigation of its interaction with the respective starting materials. In addition, the analytical methods applied in this thesis in order to identify and characterize the compounds are just as essential as the synthesis strategies. X-ray diffraction on single crystals and on powders was carried out as the main analytical method while being supported by quantitative and qualitative 1 H and 31 P solid-state NMR measurements, FTIR and energy-dispersive X-ray (EDX) spectroscopy, as well as electron microscopy methods including both imaging and diffraction techniques. Implied by the large number of novel structures investigated, theoretical studies including topological analysis, calculations of lattice energies and bond-valence sums also played a major role in this thesis. Optical analysis methods such as reflectance spectroscopy, luminescence microscopy and photoluminescence measurements helped to determine the luminescence properties of some of the presented compounds.

  2. Synthesis, crystal structure, spectroscopic characterization and nonlinear optical properties of Co(II)- picolinate complex

    Energy Technology Data Exchange (ETDEWEB)

    Tamer, Ömer, E-mail: omertamer@sakarya.edu.tr; Avcı, Davut; Atalay, Yusuf

    2015-11-15

    A cobalt(II) complex of picolinate was synthesized, and its structure was fully characterized by the applying of X-ray diffraction method as well as FT-IR, FT-Raman and UV–vis spectroscopies. In order to both support the experimental results and convert study to more advanced level, density functional theory calculations were performed by using B3LYP level. Single crystal X-ray structural analysis shows that cobalt(II) ion was located to the center of distorted octahedral geometry. The C=O, C=C and C=N stretching vibrations were found as highly active and strong peaks, inducing the molecular charge transfer within Co(II) complex. The small energy gap between frontier molecular orbital energies was another indicator of molecular charge transfer interactions within Co(II) complex. The nonlinear optical properties of Co(II) complex were investigated at DFT/B3LYP level, and the hypepolarizability parameter was found to be decreased due to the presence of inversion symmetry. The natural bond orbital (NBO) analysis was performed to investigate molecular stability, hyperconjugative interactions, intramolecular charge transfer (ICT) and bond strength for Co(II) complex. Finally, molecular electrostatic potential (MEP) and spin density distributions for Co(II) complex were evaluated. - Highlights: • Co(II) complex of picolinate was prepared. • Its FT-IR, FT-Raman and UV–vis spectra were measured. • DFT calculations were performed to support experimental results. • Small HOMO-LUMO energy gap is an indicator of molecular charge transfer. • Spin density localized on Co(II) as well as O and N atoms.

  3. Acquisition of Single Crystal Growth and Characterization Equipment. Final report

    International Nuclear Information System (INIS)

    Maple, M. Brian; Zocco, Diego A.

    2008-01-01

    Final Report for DOE Grant No. DE-FG02-04ER46178 'Acquisition of Single Crystal Growth and Characterization Equipment'. There is growing concern in the condensed matter community that the need for quality crystal growth and materials preparation laboratories is not being met in the United States. It has been suggested that there are too many researchers performing measurements on too few materials. As a result, many user facilities are not being used optimally. The number of proficient crystal growers is too small. In addition, insufficient attention is being paid to the enterprise of finding new and interesting materials, which is the driving force behind much of condensed matter research and, ultimately, technology. While a detailed assessment of this situation is clearly needed, enough evidence of a problem already exists to compel a general consensus that the situation must be addressed promptly. This final report describes the work carried out during the last four years in our group, in which a state-of-the-art single crystal growth and characterization facility was established for the study of novel oxides and intermetallic compounds of rare earth, actinide and transition metal elements. Research emphasis is on the physics of superconducting (SC), magnetic, heavy fermion (HF), non-Fermi liquid (NFL) and other types of strongly correlated electron phenomena in bulk single crystals. Properties of these materials are being studied as a function of concentration of chemical constituents, temperature, pressure, and magnetic field, which provide information about the electronic, lattice, and magnetic excitations at the root of various strongly correlated electron phenomena. Most importantly, the facility makes possible the investigation of material properties that can only be achieved in high quality bulk single crystals, including magnetic and transport phenomena, studies of the effects of disorder, properties in the clean limit, and spectroscopic and scattering

  4. [Synthesis and Characterization of a Sugar Based Electrolyte for Thin-film Polymer Batteries

    Science.gov (United States)

    1998-01-01

    The work performed during the current renewal period, March 1,1998 focused primarily on the synthesis and characterization of a sugar based electrolyte for thin-film polymer batteries. The initial phase of the project involved developing a suitable sugar to use as the monomer in the polymeric electrolyte synthesis. The monomer has been synthesized and characterized completely. Overall the yield of this material is high and it can be produced in relatively large quantity easily and in high purity. The scheme used for the preparation of the monomer is outlined along with pertinent yields.

  5. Growth of emerald single crystals

    International Nuclear Information System (INIS)

    Bukin, G.V.; Godovikov, A.A.; Klyakin, V.A.; Sobolev, V.S.

    1986-01-01

    In addition to its use for jewelry, emerald can also be used in low-noise microwave amplifiers. The authors discuss flux crystallization of emerald and note that when emerald is grown by this method, it is desirable to use solvents which dissolve emerald with minimum deviations from congruence but at the same time with sufficient high efficiency. Emerald synthesis and crystal growth from slowly cooled solutions is discussed as another possibility. The techniques are examined. Vapor synthesis and growht of beryl crystals re reviewed and the authors experimentally study the seeded CVD crystallization of beryl from BeO, Al 2 O 3 and SiO 2 oxides, by using complex compounds as carrier agents. The color of crystals of emerald and other varieties of beryl is detemined by slelective light absorption in teh visible part of the spectrum and depends on the density and structural positions of chromphore ions: chromium, iron, vanadium, nickel, manganese and cobalt

  6. Characterization and inhibitive study of gel-grown hydroxyapatite crystals at physiological temperature

    Science.gov (United States)

    Parekh, Bharat; Joshi, Mihir; Vaidya, Ashok

    2008-04-01

    Hydroxyapatite is very useful for various biomedical applications, due to its chemical similarity with mineralized bone of human. Hydroxyapatite is also responsible for arthropathy (joint disease). In the present study, the growth of hydroxyapatite crystals was carried out by using single-diffusion gel growth technique in silica hydro gel media, at physiological temperature. The growth of hydroxyapatite crystals under slow and controlled environment in gel medium can be simulated in a simple manner to the growth in human body. The crystals, formed in the Liesegang rings, were characterized by powder XRD, FTIR and dielectric study. The diffusion study is also carried out for the hydroxyapatite crystals using the moving boundary model. The inhibitive influence of various Ayurvedic medicinal plant extracts such as Boswellia serrata gum resin , Tribulus terrestris fruits, Rotula aquatica roots, Boerhaavia diffusa roots and Commiphora wightii, on the growth of hydroxyapatite was studied. Roots of R. aquatica and B. diffusa show some inhibition of the hydroxyapatite crystals in vitro. This preclinical study will be helpful to design the therapy for prevention of hydroxyapatite-based ailments.

  7. Growth, structural and magnetic characterization of Al-substituted barium hexaferrite single crystals

    International Nuclear Information System (INIS)

    Vinnik, D.A.; Zherebtsov, D.A.; Mashkovtseva, L.S.; Nemrava, S.; Bischoff, M.; Perov, N.S.; Semisalova, A.S.; Krivtsov, I.V.; Isaenko, L.I.; Mikhailov, G.G.; Niewa, R.

    2014-01-01

    Highlights: • Growth of large Al-substituted crystals BaFe 12−x Al x O 19. • Al-content controllable by flux composition. • Crystallographic site preference of Al unraveled. • Magnetic characterization depending on Al-content. - Abstract: Large single crystals of aluminum-substituted M-type barium hexaferrite BaFe 12−x Al x O 19 were obtained from carbonate flux. The Al content in the crystals can be controlled via the Al content of the flux up to x = 1.1 according to single crystal X-ray structure refinements. Al shows a distinct preference to substitute Fe on crystallographic sites with high coordination numbers by oxygen atoms, whereas no significant amounts of Al can be found on a tetrahedrally coordinated site. An increasing amount of the aluminum dopant results in a monotonous reduction of the Curie temperature from 440 to 415 °C and the saturation magnetization at room temperature from 68 to 57 emu/g for single crystal and from 61 to 53 emu/g for powder samples

  8. Synthesis of Analcime Crystals and Simultaneous Potassium Extraction from Natrolite Syenite

    Directory of Open Access Journals (Sweden)

    Jian Chen

    2017-01-01

    Full Text Available Analcime single crystals were successfully synthesized from natrolite syenite powder (K2O 10.89% and 92.6% of potassium was extracted simultaneously by means of soda roasting followed by alkali-hydrothermal method. Effects of NaOH concentration, reaction temperature, and holding period on the analcime formation and potassium extraction were investigated systemically. The results indicated that NaOH concentration plays an important role in determining the chemical composition of zeolites and size distribution; by turning the NaOH concentrations, three different pure zeolites (i.e., the phillipsite-Na, the analcime, and the sodalite were prepared. Besides, a higher temperature could accelerate the dissolution of K+ ions and enhance the crystallinity degree of zeolite. The reactions involved in the analcime synthesis can be summarized as follows: sodium aluminum silicate dissolution → precipitation and dissolution of metastable zeolite-P → analcime nucleation → analcime growth. The extraction ratio of K+ is associated with the types of synthesized zeolites, among which analcime is the most effective to promote potassium leaching out from zeolite lattice position. The optimal condition for analcime crystallization and K+ leaching is found to be as follows: 175°C for 4 h in 0.5 mol/L NaOH solution.

  9. Effect of reducing conditions of synthesis on the character of the crystallization of phosphate glasses

    Energy Technology Data Exchange (ETDEWEB)

    Alekseeva, I.P.; Karapetyan, G.O.; Milyukov, E.M.; Rusan, V.V.

    1986-03-01

    The authors investigate the effect of synthesis conditions on the properties of phosphate glasses with a high concentration of rare-earth elements (REE) which are promising materials for quantum electronics. Particular attention was paid to the character of the crystallization of the glasses. A model glass of the composition La/sub 2/O/sub 3/ X 3P/sub 2/O/sub 5/ was studied which is transparent in the visible and near-IR regions of the spectrum and produced commercially.

  10. Synthesis, Characterization, Crystal Structure and Antibacterial Activities of Transition Metal(II Complexes of the Schiff Base 2-[(4-Methylphenyliminomethyl]-6-methoxyphenol

    Directory of Open Access Journals (Sweden)

    Guo-Liang Zhao

    2009-05-01

    Full Text Available Five transition metal(II complexes, [ML2Cl2] 1~5, were synthesized from the reaction of MCl2·nH2O (M = Mn, Co, Ni, Cu, Cd and the Schiff base ligand 2-[(4-methylphenyliminomethyl]-6-methoxyphenol (C15H15NO2, L, obtained by condensation of o-vanillin (2-hydroxy-3-methoxybenzaldehyde with p-toluidine. They were characterized by elemental analysis, molar conductance, FT-IR spectra, thermal analysis. The structure of complex 1 was determined by single-crystal X-ray diffraction. Its crystal structure is of monoclinic system, space group P21/c with a = 9.0111(18 Å, b = 11.222(2 Å, c =28.130 (6 Å, α = 90 º, β = 92.29(3 º, γ = 90 º, V = 2867.6(10 Å3, Z = 4. The Mn atom is six-coordinate and displays distorted octahedral geometry.The Schiff base ligand and its complexes have been tested in vitro to evaluate their antibacterial activity against bacteria, viz., Escherichia coli, Staphylococcus aureus and Bacillus subtilis. It has been found that the complexes have higher activity than the corresponding free Schiff base ligand against the same bacteria.

  11. Raman analysis of gold on WSe2 single crystal film

    International Nuclear Information System (INIS)

    Mukherjee, Bablu; Sun Leong, Wei; Li, Yida; Thong, John T L; Gong, Hao; Sun, Linfeng; Xiang Shen, Ze; Simsek, Ergun

    2015-01-01

    Synthesis and characterization of high-quality single-crystal tungsten diselenide (WSe 2 ) films on a highly insulating substrate is presented. We demonstrate for the first time that the presence of gold (Au) nanoparticles in the basal plane of a WSe 2 film can enhance its Raman scattering intensity. The experimentally observed enhancement ratio in the Raman signal correlates well with the simulated electric field intensity using both three-dimensional electromagnetic software and theoretical calculation considering layered medium coupled-dipole approximation (LM-CDA). This work serves as a guideline for the use of Au nanoparticles on WSe 2 single-crystal thin films for surface enhanced Raman scattering (SERS) applications in the future. (paper)

  12. Synthesis and characterization of ZIF-69 membranes and separation for CO2/CO mixture

    KAUST Repository

    Liu, Yunyang

    2010-05-01

    Continuous and c-oriented ZIF-69 membranes were successfully synthesized on porous alpha-alumina substrates by an in situ solvothermal method. The membranes were characterized by XRD, SEM and single-gas permeation tests. The BET measurements on crystals taken from the same mother liquor that was used for membrane synthesis yield a Langmuir surface area of 1138 m(2)/g. The stability of the membrane towards heat and different solvents were studied. Single-gas permeation experiments through ZIF-69 membranes were carried out by a vacuum method at room temperature using H-2, CH4, CO, CO2 and SF6, respectively. The permeances were in the order of H-2 > CO2 > CH4 > CO > SF6. The separation of CO2/CO gas mixture was investigated by gas chromatograph (GC) and the permselectivity of CO2/CO was 3.5 +/- 0.1 with CO2 permeance of 3.6 +/- 0.3 x 10(-8) mol m(-2) s(-1) Pa-1 at room temperature. (C) 2010 Elsevier B.V. All rights reserved.

  13. Prediction and theoretical characterization of p-type organic semiconductor crystals for field-effect transistor applications.

    Science.gov (United States)

    Atahan-Evrenk, Sule; Aspuru-Guzik, Alán

    2014-01-01

    The theoretical prediction and characterization of the solid-state structure of organic semiconductors has tremendous potential for the discovery of new high performance materials. To date, the theoretical analysis mostly relied on the availability of crystal structures obtained through X-ray diffraction. However, the theoretical prediction of the crystal structures of organic semiconductor molecules remains a challenge. This review highlights some of the recent advances in the determination of structure-property relationships of the known organic semiconductor single-crystals and summarizes a few available studies on the prediction of the crystal structures of p-type organic semiconductors for transistor applications.

  14. Preliminary characterization of (nucleoside-2′-O-)-methyltransferase crystals from Meaban and Yokose flaviviruses

    International Nuclear Information System (INIS)

    Mastrangelo, Eloise; Bollati, Michela; Milani, Mario; Lamballeire, Xavier de; Brisbare, Nadege; Dalle, Karen; Lantez, Violaine; Egloff, Marie-Pierre; Coutard, Bruno; Canard, Bruno; Gould, Ernest; Forrester, Naomi; Bolognesi, Martino

    2006-01-01

    Two methyltransferases from flaviviruses (Meaban and Yokose viruses) have been overexpressed and crystallized. Diffraction data and characterization of the two crystal forms are presented, together with a preliminary molecular-replacement solution for both enzymes. Viral methyltranferases (MTase) are involved in the third step of the mRNA-capping process, transferring a methyl group from S-adenosyl-l-methionine (SAM) to the capped mRNA. MTases are classified into two groups: (guanine-N7)-methyltransferases (N7MTases), which add a methyl group onto the N7 atom of guanine, and (nucleoside-2′-O-)-methyltransferases (2′OMTases), which add a methyl group to a ribose hydroxyl. The MTases of two flaviviruses, Meaban and Yokose viruses, have been overexpressed, purified and crystallized in complex with SAM. Characterization of the crystals together with details of preliminary X-ray diffraction data collection (at 2.8 and 2.7 Å resolution, respectively) are reported here. The sequence homology relative to Dengue virus 2′OMTase and the structural conservation of specific residues in the putative active sites suggest that both enzymes belong to the 2′OMTase subgroup

  15. Preliminary characterization of (nucleoside-2′-O-)-methyltransferase crystals from Meaban and Yokose flaviviruses

    Energy Technology Data Exchange (ETDEWEB)

    Mastrangelo, Eloise; Bollati, Michela; Milani, Mario [Department of Biomolecular Sciences and Biotechnology, CNR-INFM, University of Milano, Via Celoria 26, 20133 Milano (Italy); Lamballeire, Xavier de; Brisbare, Nadege [Unité des Virus Emergents, Faculté de Médecine, 27 Boulevard Jean Moulin, 13005 Marseille (France); Dalle, Karen; Lantez, Violaine; Egloff, Marie-Pierre; Coutard, Bruno; Canard, Bruno [Laboratoire Architecture et Fonction des Macromolécules Biologiques, UMR 6098 CNRS ESIL, Case 932, 163 Avenue de Luminy, 13288 Marseille CEDEX 9 (France); Gould, Ernest; Forrester, Naomi [CEH Oxford, Mansfield Road, Oxford OX1 3SR (United Kingdom); Bolognesi, Martino, E-mail: martino.bolognesi@unimi.it [Department of Biomolecular Sciences and Biotechnology, CNR-INFM, University of Milano, Via Celoria 26, 20133 Milano (Italy)

    2006-08-01

    Two methyltransferases from flaviviruses (Meaban and Yokose viruses) have been overexpressed and crystallized. Diffraction data and characterization of the two crystal forms are presented, together with a preliminary molecular-replacement solution for both enzymes. Viral methyltranferases (MTase) are involved in the third step of the mRNA-capping process, transferring a methyl group from S-adenosyl-l-methionine (SAM) to the capped mRNA. MTases are classified into two groups: (guanine-N7)-methyltransferases (N7MTases), which add a methyl group onto the N7 atom of guanine, and (nucleoside-2′-O-)-methyltransferases (2′OMTases), which add a methyl group to a ribose hydroxyl. The MTases of two flaviviruses, Meaban and Yokose viruses, have been overexpressed, purified and crystallized in complex with SAM. Characterization of the crystals together with details of preliminary X-ray diffraction data collection (at 2.8 and 2.7 Å resolution, respectively) are reported here. The sequence homology relative to Dengue virus 2′OMTase and the structural conservation of specific residues in the putative active sites suggest that both enzymes belong to the 2′OMTase subgroup.

  16. SYNTHESIS, THERMAL STUDIES AND CRYSTAL STRUCTURE OF 4-AMINOPYRIDINIUM SEMI-OXALATE HEMIHYDRATE

    Directory of Open Access Journals (Sweden)

    CECILIA CHACÓN

    2017-06-01

    Full Text Available The title compound has been synthesized by grinding in an agate mortar. Its structure was characterized by TGA-DSC studies and single-crystal X-ray diffraction. This compound crystallize in the monoclinic system with space group C2/c, Z = 4, and unit cell parameters a = 16.109(2 Å, b = 5.748(7 Å, c = 20.580(3 Å, β = 107.36(1°. The salt, C2HO4-.C5H7N+.0.5 H2O, is an ionic ensemble assisted by hydrogen bonds established between 4-aminopyridinium cations, oxalate anions and water molecules. The three components thus construct a supramolecular assembly with a three-dimensional hydrogen bonded framework.

  17. Crystallization and preliminary X-ray characterization of the nitrile reductase QueF: a queuosine-biosynthesis enzyme

    International Nuclear Information System (INIS)

    Swairjo, Manal A.; Reddy, Robert R.; Lee, Bobby; Van Lanen, Steven G.; Brown, Shannon; Crécy-Lagard, Valérie de; Iwata-Reuyl, Dirk; Schimmel, Paul

    2005-01-01

    Structural informatics and modelling correctly predicted that substrate was required to obtain diffracting crystals of the first characterized nitrile oxidoreductase: the homododecameric QueF. QueF (MW = 19.4 kDa) is a recently characterized nitrile oxidoreductase which catalyzes the NADPH-dependent reduction of 7-cyano-7-deazaguanine (preQ 0 ) to 7-aminomethyl-7-deazaguanine, a late step in the biosynthesis of the modified tRNA nucleoside queuosine. Initial crystals of homododecameric Bacillus subtilis QueF diffracted poorly to 8.0 Å. A three-dimensional model based on homology with the tunnel-fold enzyme GTP cyclohydrolase I suggested catalysis at intersubunit interfaces and a potential role for substrate binding in quaternary structure stabilization. Guided by this insight, a second crystal form was grown that was strictly dependent on the presence of preQ 0 . This crystal form diffracted to 2.25 Å resolution

  18. Sterically demanding diphosphonite ligands - synthesis and application in nickel-catalyzed isomerization of 2-methyl-3-butenenitrile

    NARCIS (Netherlands)

    Vlugt, van der J.I.; Hewat, A.C.; Neto, S.; Sablong, R.J.; Mills, A.M.; Lutz, M.; Spek, A.L.; Müller, C.; Vogt, D.

    2004-01-01

    The synthesis of a novel class of sterically demanding diphosphonites 1-8, based on rigid backbones, is described. The starting materials are all commercially available and the methodology allows for a modular approach. All ligands have been fully characterized, including an X-ray crystal structure

  19. Shock and Microstructural Characterization of the α-ω Phase Transition in Titanium Crystals

    Science.gov (United States)

    Morrow, Benjamin M.; Rigg, Paulo A.; Jones, David R.; Addessio, Francis L.; Trujillo, Carl P.; Saavedra, Ramon A.; Martinez, Daniel T.; Cerreta, Ellen K.

    2017-12-01

    A multicrystal comprised of a small number of large crystals of high-purity titanium and a [0001] oriented high-purity single crystal titanium sample were shock loaded using gas gun plate impact experiments. Tests were performed at stresses above the α {-}ω phase transition stress (for high-purity polycrystalline specimens) to observe the behavior of oriented crystals under similar conditions. Post-mortem characterization of the shocked microstructure was conducted on the single crystal sample to measure textures, and quantify phases and twinning. The apparent activation of plastic and transformation mechanisms was dependent upon crystal orientation. Specifically, the [0001] crystal showed a higher Hugoniot elastic limit than the [10\\bar{1}0] or [3\\bar{1}\\bar{4}4] orientations. The slope of velocity as a function of time was lower in the [0001] orientation than the other orientations during plastic deformation, indicating sluggish transformation kinetics for the α to ω phase transition for the [0001] oriented crystal. Microtexture measurements of a recovered [0001] oriented single crystal revealed the presence of retained ω phase after unloading, with orientations of the constituent phase fractions indicative of the forward α → ω transition, rather than the reverse ω → α transition, suggesting that the material never achieved a state of 100% ω phase.

  20. All-optically tunable waveform synthesis by a silicon nanowaveguide ring resonator coupled with a photonic-crystal fiber frequency shifter

    KAUST Repository

    Savvin, Aleksandr D.

    2011-03-01

    A silicon nanowaveguide ring resonator is combined with a photonic-crystal fiber (PCF) frequency shifter to demonstrate an all-optically tunable synthesis of ultrashort pulse trains, modulated by ultrafast photoinduced free-carrier generation in the silicon resonator. Pump-probe measurements performed with a 50-fs, 625-nm second-harmonic output of a Cr:forsterite laser, used as a carrier-injecting pump, and a 1.50-1.56-μm frequency-tunable 100-fs soliton output of a photonic-crystal fiber, serving as a probe, resolve tunable ultrafast oscillatory features in the silicon nanowaveguide resonator response. © 2010 Elsevier B.V. All rights reserved.

  1. All-optically tunable waveform synthesis by a silicon nanowaveguide ring resonator coupled with a photonic-crystal fiber frequency shifter

    KAUST Repository

    Savvin, Aleksandr D.; Melnikov, Vasily; Fedotov, Il'ya V.; Fedotov, Andrei B.; Perova, Tatiana S.; Zheltikov, Aleksei M.

    2011-01-01

    A silicon nanowaveguide ring resonator is combined with a photonic-crystal fiber (PCF) frequency shifter to demonstrate an all-optically tunable synthesis of ultrashort pulse trains, modulated by ultrafast photoinduced free-carrier generation in the silicon resonator. Pump-probe measurements performed with a 50-fs, 625-nm second-harmonic output of a Cr:forsterite laser, used as a carrier-injecting pump, and a 1.50-1.56-μm frequency-tunable 100-fs soliton output of a photonic-crystal fiber, serving as a probe, resolve tunable ultrafast oscillatory features in the silicon nanowaveguide resonator response. © 2010 Elsevier B.V. All rights reserved.

  2. Synthesis, Characterization and Catalytic Activity of Cu/Cu2O Nanoparticles Prepared in Aqueous Medium

    Directory of Open Access Journals (Sweden)

    Sayed M. Badawy

    2015-07-01

    Full Text Available Copper/Copper oxide (Cu/Cu2O nanoparticles were synthesized by modified chemical reduction method in an aqueous medium using hydrazine as reducing agent and copper sulfate pentahydrate as precursor. The Cu/Cu2O nanoparticles were characterized by X-ray Diffraction (XRD, Energy Dispersive X-ray Fluorescence (EDXRF, Scanning Electron Microscope (SEM, and Transmission Electron Microscope (TEM. The analysis revealed the pattern of face-centered cubic (fcc crystal structure of copper Cu metal and cubic cuprites structure for Cu2O. The SEM result showed monodispersed and agglomerated particles with two micron sizes of about 180 nm and 800 nm, respectively. The TEM result showed few single crystal particles of face-centered cubic structures with average particle size about 11-14 nm. The catalytic activity of Cu/Cu2O nanoparticles for the decomposition of hydrogen peroxide was investigated and compared with manganese oxide MnO2. The results showed that the second-order equation provides the best correlation for the catalytic decomposition of H2O2 on Cu/Cu2O. The catalytic activity of hydrogen peroxide by Cu/Cu2O is less than the catalytic activity of MnO2 due to the presence of copper metal Cu with cuprous oxide Cu2O. © 2015 BCREC UNDIP. All rights reservedReceived: 6th January 2015; Revised: 14th March 2015; Accepted: 15th March 2015How to Cite: Badawy, S.M., El-Khashab, R.A., Nayl, A.A. (2015. Synthesis, Characterization and Catalytic Activity of Cu/Cu2O Nanoparticles Prepared in Aqueous Medium. Bulletin of Chemical Reaction Engineering & Catalysis, 10 (2: 169-174. (doi:10.9767/bcrec.10.2.7984.169-174 Permalink/DOI: http://dx.doi.org/10.9767/bcrec.10.2.7984.169-174  

  3. Synthesis and characterization of innovative insulation materials

    Directory of Open Access Journals (Sweden)

    Skaropoulou Aggeliki

    2018-01-01

    Full Text Available Insulation elements are distinguished in inorganic fibrous and organic foamed materials. Foamed insulation materials are of great acceptance and use, but their major disadvantage is their flammability. In case of fire, they tend to transmit the flame producing toxic gases. In this paper, the synthesis and characterization of innovative inorganic insulation materials with properties competitive to commercial is presented. Their synthesis involves the mixing of inorganic raw material and water with reinforcing agent or/and foaming agent leading to the formation of a gel. Depending on raw materials nature, the insulation material is produced by freeze drying or ambient drying techniques of the gel. The raw material used are chemically benign and abundantly available materials, or industrial by-products and the final products are non-toxic and, in some cases, non-flammable. Their density and thermal conductivity was measured and found 0.02-0.06 g/cm3 and 0.03-0.04 W/mK, respectively.

  4. Sol-gel synthesis of Bi3.25La0.75Ti3O12 nanotubes

    International Nuclear Information System (INIS)

    Wang Wen; Ke Hua; Rao Jiancun; Feng Jinbiao; Feng Ming; Jia Dechang; Zhou Yu

    2011-01-01

    Research highlights: → One-dimensional (1D) ferroelectrics have been successfully synthesized. The sol-gel template synthesis is a versatile and inexpensive technique for producing nanostructures, and particularly facilitates the fabrication of complex oxide nanotubes or nanowires. Compared with the synthesis of the general nanotubes such as carbon nanotubes with simple crystal structure, the synthesis of ferroelectric compound is difficult due to the multielement and the complex crystal structures of these ferroelectrics. Herein, we report the synthesis of one-dimensional BLT nanotubes on anodic alumina (AAO) templates by immersing a template membrane in sol without polymeric additive. - Abstract: Ferroelectric Bi 3.25 La 0.75 Ti 3 O 12 (BLT) nanotubes were synthesized by sol-gel technique using nanochannel porous anodic aluminum oxide (AAO) templates, and were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM) and high resolution transmission electron microscopy (HRTEM). BLT nanotubes with diameter of around 240 nm and the wall thickness of about 25 nm exhibited a single orthorhombic perovskite structure and highly preferential crystal growth along the [1 1 7] orientation, which have smooth wall morphologies and well-defined diameters corresponding to the diameter of the applied template. The formation mechanism of BLT nanotubes was discussed.

  5. Synthesis and characterization of nano silver ferrite composite

    International Nuclear Information System (INIS)

    Murthy, Y.L.N.; Kondala Rao, T.; Kasi viswanath, I.V.; Singh, Rajendra

    2010-01-01

    We report the synthesis of nano sized silver ferrite composite having the empirical formula AgFeO 2 by a co-precipitation method. The resulting powders are thin platelets, transparent and a rich ruby red in color in transmission. The X-ray diffraction (XRD) powder data consisted of only nine reflections, and the analysis showed the unit cell to be rhombohedral. The powders showed extensive XRD line broadening and the sizes of the crystals are calculated to be in the range 4-36.5 nm. The morphology of the silver ferrite composite studied using scanning electron microscope showed nano sized particles. The particle size is found to increase with increase in annealing temperature. The magnetic behavior, measured using a vibrating sample magnetometer, indicated a change from paramagnetic to ferromagnetic with increase in particle size.

  6. Quantitative phase analysis and microstructure characterization of magnetite nanocrystals obtained by microwave assisted non-hydrolytic sol–gel synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Sciancalepore, Corrado, E-mail: corrado.sciancalepore@unimore.it [Department of Engineering “Enzo Ferrari”, University of Modena and Reggio Emilia, Via Pietro Vivarelli 10, 41100 Modena (Italy); Bondioli, Federica [Department of Industrial Engineering, University of Parma, Parco Area delle Scienze, 181/A, 43124 Parma (Italy); INSTM Consortium, Via G. Giusti 9, 51121 Firenze (Italy); Manfredini, Tiziano [Department of Engineering “Enzo Ferrari”, University of Modena and Reggio Emilia, Via Pietro Vivarelli 10, 41100 Modena (Italy); INSTM Consortium, Via G. Giusti 9, 51121 Firenze (Italy); Gualtieri, Alessandro [Department of Chemical and Geological Science, University of Modena and Reggio Emilia, Via S. Eufemia 19, 41121 Modena Italy (Italy)

    2015-02-15

    An innovative preparation procedure, based on microwave assisted non-hydrolytic sol–gel synthesis, to obtain spherical magnetite nanoparticles was reported together with a detailed quantitative phase analysis and microstructure characterization of the synthetic products. The nanoparticle growth was analyzed as a function of the synthesis time and was described in terms of crystallization degree employing the Rietveld method on the magnetic nanostructured system for the determination of the amorphous content using hematite as internal standard. Product crystallinity increases as the microwave thermal treatment is increased and reaches very high percentages for synthesis times longer than 1 h. Microstructural evolution of nanocrystals was followed by the integral breadth methods to obtain information on the crystallite size-strain distribution. The results of diffraction line profile analysis were compared with nanoparticle grain distribution estimated by dimensional analysis of the transmission electron microscopy (TEM) images. A variation both in the average grain size and in the distribution of the coherently diffraction domains is evidenced, allowing to suppose a relationship between the two quantities. The traditional integral breadth methods have proven to be valid for a rapid assessment of the diffraction line broadening effects in the above-mentioned nanostructured systems and the basic assumption for the correct use of these methods are discussed as well. - Highlights: • Fe{sub 3}O{sub 4} nanocrystals were obtained by MW-assisted non-hydrolytic sol–gel synthesis. • Quantitative phase analysis revealed that crystallinity up to 95% was reached. • The strategy of Rietveld refinements was discussed in details. • Dimensional analysis showed nanoparticles ranging from 4 to 8 nm. • Results of integral breadth methods were compared with microscopic analysis.

  7. Quantitative phase analysis and microstructure characterization of magnetite nanocrystals obtained by microwave assisted non-hydrolytic sol–gel synthesis

    International Nuclear Information System (INIS)

    Sciancalepore, Corrado; Bondioli, Federica; Manfredini, Tiziano; Gualtieri, Alessandro

    2015-01-01

    An innovative preparation procedure, based on microwave assisted non-hydrolytic sol–gel synthesis, to obtain spherical magnetite nanoparticles was reported together with a detailed quantitative phase analysis and microstructure characterization of the synthetic products. The nanoparticle growth was analyzed as a function of the synthesis time and was described in terms of crystallization degree employing the Rietveld method on the magnetic nanostructured system for the determination of the amorphous content using hematite as internal standard. Product crystallinity increases as the microwave thermal treatment is increased and reaches very high percentages for synthesis times longer than 1 h. Microstructural evolution of nanocrystals was followed by the integral breadth methods to obtain information on the crystallite size-strain distribution. The results of diffraction line profile analysis were compared with nanoparticle grain distribution estimated by dimensional analysis of the transmission electron microscopy (TEM) images. A variation both in the average grain size and in the distribution of the coherently diffraction domains is evidenced, allowing to suppose a relationship between the two quantities. The traditional integral breadth methods have proven to be valid for a rapid assessment of the diffraction line broadening effects in the above-mentioned nanostructured systems and the basic assumption for the correct use of these methods are discussed as well. - Highlights: • Fe 3 O 4 nanocrystals were obtained by MW-assisted non-hydrolytic sol–gel synthesis. • Quantitative phase analysis revealed that crystallinity up to 95% was reached. • The strategy of Rietveld refinements was discussed in details. • Dimensional analysis showed nanoparticles ranging from 4 to 8 nm. • Results of integral breadth methods were compared with microscopic analysis

  8. Synthesis, characterization and magnetic property of 3D flower-like ...

    Indian Academy of Sciences (India)

    Three-dimensional (3D) flower-like cubic Ni3S4 nanoplates with single crystalline nature were successfully prepared through decomposing bis(thiourea) nickel(II) chloride crystals (BTNC). The samples were characterized by X-ray diffraction, scanning electron microscope, transmission electron microscope, selected area ...

  9. Effect of the raw material type and the reaction time on the synthesis of halloysite based Zeolite Na-P1

    Science.gov (United States)

    Meftah, Mahdi; Oueslati, Walid; Chorfi, Nejmeddine; Ben Haj Amara, Abdesslem

    Zeolites are currently one of the most important classes of inorganic materials because of their multiple applications not only as ions exchangers and molecular sieves, but also as catalysts. This works focus the synthesis and the characterization of Zeolite Na-P1 using halloysite (collected near Ain Khemouda, western Tunisia) as the starting material. Two parameters, such as the host materials type (natural or treated) and the reaction time, involved in the synthesis process are investigated. The intermediate phases and final products were characterized by X-ray diffraction, Infrared IR spectroscopy, scanning electron microscopy and high-resolution 29Si and 27Al MAS NMR. Obtained results show that the hydrothermal synthesis from natural and heated-halloysite leads to formation of homogenous Zeolite Na-P1. The difference in the crystallization/transformation time process is explained by the effect of the dissolution rate of the starting materials in sodium hydroxide solution. In the case of heated halloysite, the synthesis reaction with alkali solution occurs very readily and achieved without prior thermal activation at high temperature. The optimal conditions of Zeolite Na-P1 crystallization, from heated-halloysite, are reached at 120 °C.

  10. Synthesis and Characterization of Two New p-tert-Butylcalix[4]-arene Schiff Bases

    Directory of Open Access Journals (Sweden)

    Saeed Taghvaee Ganjali

    2001-03-01

    Full Text Available Synthesis and characterization of two new Schiff bases of p-tertbuthylcalix[4]arene (H2L1 and HL2 is described. The synthesis of H2L1 and HL2 has been achieved by the condensation of salicylaldehyde with the amine group of upper rim monoamine p-tert-butylcalix[4]arene in ethanol. These compounds have been characterized on the basis of elemental analysis and spectral data. Solvatochromicity and fluorescence properties were observed and measured for H2L1 and HL2. Solvatochromicity of these ligands indicates their potential for NLO applications.

  11. Rapid, green synthesis and surface-enhanced Raman scattering effect of single-crystal silver nanocubes

    Science.gov (United States)

    Mao, Aiqin; Jin, Xia; Gu, Xiaolong; Wei, Xiaoqing; Yang, Guojing

    2012-08-01

    Single-crystal silver (Ag) nanocubes have been synthesized by a rapid and green method at room temperature by adding sodium hydroxide solution to the mixed solutions of silver nitrate, glucose and polyvinylpyrrolidone (PVP). The X-ray diffraction (XRD), ultraviolet-visible (UV-visible) and transmission electron microscopy (TEM) were used to characterize the phase composition and morphology. The results showed that the as-prepared particles were single-crystal Ag nanocubes with edge lengths of around 77 nm and a growing direction along {1 0 0} facets. As substrates for surface-enhanced Raman scattering (SERS) experiment on crystal violet (CV), the SERS enhancement factor of the as-prepared Ag nanocubes were measured to be 5.5 × 104, indicating potential applications in chemical and biological analysis.

  12. Nano crystals for Electronic and Optoelectronic Applications

    International Nuclear Information System (INIS)

    Zhu, T.; Cloutier, S.G.; Ivanov, I; Knappenberger Jr, K.L.; Robel, I.; Zhang, F

    2012-01-01

    Electronic and optoelectronic devices, from computers and smart cell phones to solar cells, have become a part of our life. Currently, devices with featured circuits of 45 nm in size can be fabricated for commercial use. However, further development based on traditional semiconductor is hindered by the increasing thermal issues and the manufacturing cost. During the last decade, nano crystals have been widely adopted in various electronic and optoelectronic applications. They provide alternative options in terms of ease of processing, low cost, better flexibility, and superior electronic/optoelectronic properties. By taking advantage of solution-processing, self-assembly, and surface engineering, nano crystals could serve as new building blocks for low-cost manufacturing of flexible and large area devices. Tunable electronic structures combined with small exciton binding energy, high luminescence efficiency, and low thermal conductivity make nano crystals extremely attractive for FET, memory device, solar cell, solid-state lighting/display, photodetector, and lasing applications. Efforts to harness the nano crystal quantum tunability have led to the successful demonstration of many prototype devices, raising the public awareness to the wide range of solutions that nano technology can provide for an efficient energy economy. This special issue aims to provide the readers with the latest achievements of nano crystals in electronic and optoelectronic applications, including the synthesis and engineering of nano crystals towards the applications and the corresponding device fabrication, characterization and computer modeling.

  13. Synthesis, Crystal Growth, Spectroscopic and Electrical Properties of 5-tert-Butyl-1,2,3-trinitrobenzene

    Directory of Open Access Journals (Sweden)

    S. Sahaya Jude Dhas

    2013-01-01

    Full Text Available 5-tert-Butyl-1,2,3-trinitrobenzene (TBTB was synthesized and characterized by NMR so as to confirm the structure. Single crystals were obtained from methanol by solvent evaporation technique at room temperature. Optically transparent single crystals with dimension up to 17×4×3 mm3 have been grown by submerged seed solution method within a period of 30 days. The modes of vibration of different molecular groups present in the title compound were identified by FTIR and FT-Raman spectral analyses, and it was found with the tabulation that both of the spectral vibrations are very close to each other confirming the existence of specific functional groups in the crystal. Optical behaviour of the crystal was analyzed by UV-Vis absorption studies, and the value of the optical band gap energy (Eg of the crystal has been determined using the optical absorption spectrum. The dielectric behaviour and AC conductivity of the grown crystals were also analyzed, and it is shown that both properties vary with respect to frequency and do not vary in accordance with temperature.

  14. Synthesis and characterization of iron based superconductor Nd-1111

    Science.gov (United States)

    Alborzi, Z.; Daadmehr, V.

    2018-06-01

    Polycrystalline sample of NdFeAsO0.8F0.2 was prepared by one-step solid-state reaction method. The structural and electrical properties of sample were characterized through XRD pattern and the 4-probe method. The critical temperature was obtained at 56 K. The crystal structure was tetragonal with P4/nmm:2 symmetry group.

  15. Graphene optoelectronics synthesis, characterization, properties, and applications

    CERN Document Server

    bin M Yusoff, Abdul Rashid

    2014-01-01

    This first book on emerging applications for this innovative material gives an up-to-date account of the many opportunities graphene offers high-end optoelectronics.The text focuses on potential as well as already realized applications, discussing metallic and passive components, such as transparent conductors and smart windows, as well as high-frequency devices, spintronics, photonics, and terahertz devices. Also included are sections on the fundamental properties, synthesis, and characterization of graphene. With its unique coverage, this book will be welcomed by materials scientists, solid-

  16. Synthesis and characterization of triangulene

    Science.gov (United States)

    Pavliček, Niko; Mistry, Anish; Majzik, Zsolt; Moll, Nikolaj; Meyer, Gerhard; Fox, David J.; Gross, Leo

    2017-05-01

    Triangulene, the smallest triplet-ground-state polybenzenoid (also known as Clar's hydrocarbon), has been an enigmatic molecule ever since its existence was first hypothesized. Despite containing an even number of carbons (22, in six fused benzene rings), it is not possible to draw Kekulé-style resonant structures for the whole molecule: any attempt results in two unpaired valence electrons. Synthesis and characterization of unsubstituted triangulene has not been achieved because of its extreme reactivity, although the addition of substituents has allowed the stabilization and synthesis of the triangulene core and verification of the triplet ground state via electron paramagnetic resonance measurements. Here we show the on-surface generation of unsubstituted triangulene that consists of six fused benzene rings. The tip of a combined scanning tunnelling and atomic force microscope (STM/AFM) was used to dehydrogenate precursor molecules. STM measurements in combination with density functional theory (DFT) calculations confirmed that triangulene keeps its free-molecule properties on the surface, whereas AFM measurements resolved its planar, threefold symmetric molecular structure. The unique topology of such non-Kekulé hydrocarbons results in open-shell π-conjugated graphene fragments that give rise to high-spin ground states, potentially useful in organic spintronic devices. Our generation method renders manifold experiments possible to investigate triangulene and related open-shell fragments at the single-molecule level.

  17. One-step green synthesis of cuprous oxide crystals with truncated octahedra shapes via a high pressure flux approach

    International Nuclear Information System (INIS)

    Li Benxian; Wang Xiaofeng; Xia Dandan; Chu Qingxin; Liu Xiaoyang; Lu Fengguo; Zhao Xudong

    2011-01-01

    Cuprous oxide (Cu 2 O) was synthesized via reactions between cupric oxide (CuO) and copper metal (Cu) at a low temperature of 300 deg. C. This progress is green, environmentally friendly and energy efficient. Cu 2 O crystals with truncated octahedra morphology were grown under high pressure using sodium hydroxide (NaOH) and potassium hydroxide (KOH) with a molar ratio of 1:1 as a flux. The growth mechanism of Cu 2 O polyhedral microcrystals are proposed and discussed. - Graphical Abstract: The Cu 2 O crystals with truncated octahedral shape were one-step synthesized in high yield via high pressure flux method for the first time, which is green and environmentally friendly. The mechanisms of synthesis and crystal growth were discussed in this paper. Highlights: → Cuprous oxide was one-step green synthesized by high pressure flux method. → The approach was based on the reverse dismutation reactions between cupric oxide and copper metal. → This progress is green, environmentally friendly and energy efficient. → The synthesized Cu2O crystals were of truncated octahedra morphology.

  18. Influence of pressure on the crystallization of systems characterized by different intermolecular attraction

    Science.gov (United States)

    Koperwas, K.; Affouard, F.; Gerges, J.; Valdes, L.-C.; Adrjanowicz, K.; Paluch, M.

    2017-12-01

    In this paper, we examine, in terms of the classical nucleation theory, how the strengthening of the attractive intermolecular interactions influences the crystallization process for systems like Lennard-Jones at different isobaric conditions. For this purpose, we modify the standard Lennard-Jones potential, and as a result, we obtain three different systems characterized by various strengths of attractive potentials occurring between molecules, which are in direct relationship to the physical quantities describing molecules, e.g., its polarizability or dipole moment. Based on performed analysis, we demonstrate that the molecular attraction primarily impacts the thermodynamics of the interface between liquid and crystal. This is reflected in the behavior of nucleation and overall crystallization rates during compression of the system.

  19. Growth and Characterization of ZnTe Crystal

    International Nuclear Information System (INIS)

    Nann Thazin

    2011-12-01

    High quality ZnTe crystals have been synthesized by vapor Transport method. The grown crystals were p-type. The concentration and mobility were 2.5 x 10 16 cm-3 and 23 cm2/Vs at 300K, according to Hall effect measurements. Surface morphology of the crystal was investigated by scanning electron microscope (SEM). Crystal orientation and lattice parameters of the crystals were also analysed by XRD. From X-ray diffraction studies the structure of the grown crystals were found to be zinc-blende. The crystal emitted light in the visible range at room temperature.

  20. Growth and characterization of air annealing Mn-doped YAG:Ce single crystal for LED

    International Nuclear Information System (INIS)

    Xiang, Weidong; Zhong, Jiasong; Zhao, Yinsheng; Zhao, Binyu; Liang, Xiaojuan; Dong, Yongjun; Zhang, Zhimin; Chen, Zhaoping; Liu, Bingfeng

    2012-01-01

    Highlights: ► The YAG:Ce,Mn single crystal was well synthesized by the Czochralski (CZ) method. ► The emission intensity of the sample has been influenced after annealing. ► Annealed in the air at 1200 °C was the most optimal annealing condition. ► The single crystal could be used in the white light LED which emitted by blue light. - Abstract: The growth of Mn-doped YAG:Ce (yttrium aluminum garnet doped cerium) single crystal by the Czochralski (CZ) method and the characterization of its spectroscopy and color-electric parameters are presented. The absorption spectra indicate that the crystal absorbed highly in the 300–500 nm wavelength range. The emission spectrum of the crystal consists of a peak around 538 nm when excited by 460 nm blue light, which prove the YAG:Ce,Mn single crystal could be used in the white light emitting doides (LED). The different charges of Mn ions have different luminescence properties, and the air annealing process for the single crystal would change the concentration of Mn ions with different charges, which could influence the emission intensity of the single crystal.

  1. Synthesis, characterization and crystal structure of [Cu2(LH2]•(ClO42. Influence of the weak Cu•••O(perchlorate interaction on the structure of Cu2N2O2 metallocycle

    Directory of Open Access Journals (Sweden)

    Mirković Marija

    2014-01-01

    Full Text Available The diimine-dioxime ligand, 4,9-diaza-3,10-diethyl-3,9-dodecadiene-2,11-dione bisoxime (LH2, containing a N4 donor set was prepared by Schiff base condensation of 2-hydroxyimino-3-pentanone and 1,4-diaminobutane in two ways: in protic and in aprotic solvent. Higher yield of (LH2 imine was obtained when the synthesis was carried out using protic solvent (C2H5OH instead of aprotic benzene (78% and 30%, respectively. Cu(II metal complex of diimine-dioxime was synthesized in CH3OH from metal salt and LH2 in mole ratio 1:1. The isolated complex was characterized by the elemental analysis, IR spectroscopy and cyclic voltammetry. The structure of [Cu2(LH2]•(ClO42 was determined by the single-crystal X-ray diffraction analysis. Comparison with the structurally related diimine-dioxime Cu(II complexes revealed the influence of the weak Cu•••O(perchlorate interaction on the geometry of the metallocycle. [Projekat Ministarstva nauke Republike Srbije, br. 45015, br. 172013, br. 172065 i br. 172014

  2. Microwave hydrothermal synthesis and characterization of PZT 52/48 powders

    International Nuclear Information System (INIS)

    Teixeira, G.F.; Gasparotto, G.; Santos, N.A.; Zaghete, M.A.; Varela, J.A.; Longo, E.

    2009-01-01

    Full text: Lead Zirconate Titanate (PZT) is a ceramic witch has great interest because of their ferroelectric, piezoelectric, and other electrical properties. In this work Pb(ZrxTi1-x)O3 powders were synthesized by microwave hydrothermal synthesis (M-H) at 180°C without excess lead content. This method allows obtaining particles whit nanometer size, good stoichiometric controls, high purity and crystalline degree at low temperatures and short times of synthesis. Powders were synthesized with molar concentration of 0.15 mol.L -1 during different times: 30 min, 2, 4, 6 and 8 h. After that the powders were characterized by X-ray diffraction (XRD), Field Emission Gun (FEG) and photoluminescence (PL). Through analysis it is observed that the crystalline phase of PZT is obtained from 2 hours of synthesis and this same time also presents more intense PL emission. (author)

  3. Novel polymeric potassium complex: Its synthesis, structural characterization, photoluminescence and electrochemical properties

    Energy Technology Data Exchange (ETDEWEB)

    Ceyhan, Goekhan [Chemistry Department, K.Maras Suetcue Imam University, 46100 K.Maras (Turkey); Tuemer, Mehmet, E-mail: mtumer@ksu.edu.tr [Chemistry Department, K.Maras Suetcue Imam University, 46100 K.Maras (Turkey); Koese, Muhammet; McKee, Vickie [Chemistry Department, Loughborough University, LE11 3TU Leicestershire (United Kingdom)

    2012-03-15

    In this paper, we obtained a novel poly(vanillinato potassium) complex (PVP) as a single crystal and characterized by analytical and spectroscopic methods. A single crystal of the PVP was obtained from the acetone solution. X-ray structural data show that crystals contain polymeric K{sup +} complex of vanillin. Each potassium ion in the polymeric structure is identical and seven-coordinate, bonded to two methoxy, two phenoxy and three aldehyde oxygen atoms from four vaniline molecules. Two aldehyde oxygen atoms are bridging between potassium ions. It crystallizes in the monoclinic system, space group P2{sub 1}/c, with lattice parameters a=9.6215(10) A, b=17.4139(19) A, c=9.6119(10) A, {beta}=100.457(2) Degree-Sign and Z=4. Thermal properties of the PVP were investigated by TGA, DTA and DSC methods. The electrochemical properties of the complex were studied in different solvents and at various scan rates. The luminescence properties of the complex in different solvents and at different pH values have been investigated. The results show that the complex exhibits more efficient luminescence property in CH{sub 3}CN and n-butanol. - Highlights: Black-Right-Pointing-Pointer Novel polymeric potassium complex was prepared and fully characterized. Black-Right-Pointing-Pointer X-ray crystal structure of complex was reported. Black-Right-Pointing-Pointer Electrochemical properties of compound were investigated. Black-Right-Pointing-Pointer Thermal and DSC measurements of complex were examined.

  4. Controllable synthesis and crystal structure determined upconversion luminescence properties of Tm{sup 3+} (Er{sup 3+}) ions doped YbF{sub 3} and NaYbF{sub 4} crystals

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Tao [Institute of Photonics, Faculty of Science, Ningbo University, Ningbo 315211 (China); Qin, Weiping, E-mail: wpqin@jlu.edu.cn [State Key Laboratory on Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, Changchun 130012 (China); Zhou, Jun [Institute of Photonics, Faculty of Science, Ningbo University, Ningbo 315211 (China)

    2014-04-01

    Graphical abstract: - Highlights: • The synthesis of YbF{sub 3} and NaYbF{sub 4} crystals was successfully fulfilled by hydrothermal method. • The phase and morphology of products were adjusted by changing the hydrothermal conditions. • Relatively enhanced ultraviolet upconversion emissions were observed in YbF{sub 3} nanocrystals. • The crystalline phase impact on the upconversion luminescence was systematically studied. - Abstract: The synthesis of YbF{sub 3} and NaYbF{sub 4} crystals was successfully fulfilled by a facial hydrothermal method. The phase and morphology of the products were adjusted by changing the surfactant additive and fluorine source and tuning the pH value of the initial solution. The products with various morphologies range from octahedral nanoparticles, corn-like nanobundles, nanospheres, microrods, and hollow microprisms were prepared at different conditions. The growth mechanism of these products has been systematically studied. Impressively, relatively enhanced high order ultraviolet (UV) upconversion (UC) luminescence was observed in Tm{sup 3+} (Er{sup 3+}) ions doped YbF{sub 3} nanocrystals (NCs) compared with NaYbF{sub 4} microcrystals under the excitation of 980 nm infrared laser. The investigation results reveal that the crystal symmetry of matrix has significant effect on the spectra and lifetimes of the doping lanthanide ions. The simply synthesized water soluble YbF{sub 3} NCs with efficient UV UC luminescence may find potential application in biochemistry.

  5. Electronic, electrical and magnetic ceramics synthesis and characterization

    International Nuclear Information System (INIS)

    Calix, V.S.; Saligan, P.P.; Naval, P.C.

    1989-01-01

    This paper describes the research and development activities of the Philippine Nuclear Research Institute (PNRI) on the synthesis and characterization of soft and hard ferrites and some beta alumina type superionic conductor materials. XRD, XRF and Moessbauer effect spectrometry are used to determine the structure phases, compositions and some magnetic properties of the materials. Effects of composition and preparation methods on the bulk electronic and magnetic properties are also discussed. (Auth.). 6 figs.; 3 tabs

  6. Materials-by-design: computation, synthesis, and characterization from atoms to structures

    Science.gov (United States)

    Yeo, Jingjie; Jung, Gang Seob; Martín-Martínez, Francisco J.; Ling, Shengjie; Gu, Grace X.; Qin, Zhao; Buehler, Markus J.

    2018-05-01

    In the 50 years that succeeded Richard Feynman’s exposition of the idea that there is ‘plenty of room at the bottom’ for manipulating individual atoms for the synthesis and manufacturing processing of materials, the materials-by-design paradigm is being developed gradually through synergistic integration of experimental material synthesis and characterization with predictive computational modeling and optimization. This paper reviews how this paradigm creates the possibility to develop materials according to specific, rational designs from the molecular to the macroscopic scale. We discuss promising techniques in experimental small-scale material synthesis and large-scale fabrication methods to manipulate atomistic or macroscale structures, which can be designed by computational modeling. These include recombinant protein technology to produce peptides and proteins with tailored sequences encoded by recombinant DNA, self-assembly processes induced by conformational transition of proteins, additive manufacturing for designing complex structures, and qualitative and quantitative characterization of materials at different length scales. We describe important material characterization techniques using numerous methods of spectroscopy and microscopy. We detail numerous multi-scale computational modeling techniques that complements these experimental techniques: DFT at the atomistic scale; fully atomistic and coarse-grain molecular dynamics at the molecular to mesoscale; continuum modeling at the macroscale. Additionally, we present case studies that utilize experimental and computational approaches in an integrated manner to broaden our understanding of the properties of two-dimensional materials and materials based on silk and silk-elastin-like proteins.

  7. Synthesis and characterization of nano- and microcrystalline cubes of pure and Ag-doped LiF

    Science.gov (United States)

    Alharbi, Najlaa D.; Salah, Numan; Habib, Sami S.; Alarfaj, Esam

    2013-01-01

    Lithium fluoride (LiF) produced in single crystals and doped with proper activators is a highly sensitive phosphor used in several applications such as integrated optics, colour centre laser and radiation dosimetry. In this work, we have developed a new synthetic chemical co-precipitation route for the synthesis of well-crystallized micro- and nanocrystalline cubes of pure and silver (Ag)-doped LiF. The as-synthesized samples were characterized by x-ray diffraction (XRD), scanning electron microscopy, absorption spectrum, photoluminescence (PL) and Raman spectroscopy. Size of the produced cubes could be controlled in the range 10 µm-50 nm by varying the solvent : co-solvent ratio. Micro-sized cubes could be grown in the presence of water as a solvent, while ethanol, which acts as a co-solvent, is found to be effective in reducing the size to the nanoscale. XRD results show complete crystalline structures in a griceite phase. The PL result of pure nanocubes exhibits a broad band in the range 370-550 nm, while that doped with Ag shows a prominent band at 420 nm. Raman spectra of the pure and Ag-doped LiF samples display several bands located in the range 80-236 cm-1. These results show that pure nanocubes of LiF have active colour centres without irradiation, which could be enhanced/modified by Ag dopants. This implies that these nanocubes might be useful in the development of optical devices.

  8. Synthesis and characterization of nano- and microcrystalline cubes of pure and Ag-doped LiF

    International Nuclear Information System (INIS)

    Alharbi, Najlaa D; Salah, Numan; Habib, Sami S; Alarfaj, Esam

    2013-01-01

    Lithium fluoride (LiF) produced in single crystals and doped with proper activators is a highly sensitive phosphor used in several applications such as integrated optics, colour centre laser and radiation dosimetry. In this work, we have developed a new synthetic chemical co-precipitation route for the synthesis of well-crystallized micro- and nanocrystalline cubes of pure and silver (Ag)-doped LiF. The as-synthesized samples were characterized by x-ray diffraction (XRD), scanning electron microscopy, absorption spectrum, photoluminescence (PL) and Raman spectroscopy. Size of the produced cubes could be controlled in the range 10 µm-50 nm by varying the solvent:co-solvent ratio. Micro-sized cubes could be grown in the presence of water as a solvent, while ethanol, which acts as a co-solvent, is found to be effective in reducing the size to the nanoscale. XRD results show complete crystalline structures in a griceite phase. The PL result of pure nanocubes exhibits a broad band in the range 370-550 nm, while that doped with Ag shows a prominent band at 420 nm. Raman spectra of the pure and Ag-doped LiF samples display several bands located in the range 80-236 cm -1 . These results show that pure nanocubes of LiF have active colour centres without irradiation, which could be enhanced/modified by Ag dopants. This implies that these nanocubes might be useful in the development of optical devices.

  9. Synthesis and characterization of composites of mixed oxides of iron ...

    Indian Academy of Sciences (India)

    Home; Journals; Bulletin of Materials Science; Volume 34; Issue 4. Synthesis and characterization of composites of mixed oxides of iron and neodymium in polymer matrix of aniline–formaldehyde. Sajdha H N Sheikh B L Kalsotra N Kumar S Kumar. Volume 34 Issue 4 July 2011 pp 843-851 ...

  10. Synthesis of Zeolite A from Kaolin (Shwe Taung Clay)

    International Nuclear Information System (INIS)

    Mie Mie Han Htun; Mu Mu Htay

    2010-12-01

    The synthesis of Zeolite A from locally available kaolin clay (Shwe Taung) in Myanmar has been attempted. The kaolinite was converted to metakaoli, by treating with NaOH at 820C for 1hr, and hydrothermal treatment.It was found that the solution of fused clay powder can be crystallized at 100C under ambient pressure to synthesize Zeolite A. The process variables for synthesis have been optimized in order to produce Zeolite A at a lower price. The mole ratio of SiO2/Al2O3 for kaolin was fixed at 2.54. The effects of various factors (aging time and agitation time) on the structure of the sample were extensively investigated. The Shwe Taung clay was characterized by X-ray Diffraction (XRD), X-ray fluorescence (XRF) and Scanning Electron Microscopy (SEM). The samples were characterized by XRD. The results show that the pure form Zeolite A can be prepared with a molar composition of (2.54 SiO3: Al2O3: 5.8Na2O: 256 H2O) by agitation at room temperature for 30min. The mixture was aged for 24 hour at the same temperature and crystallized at 100C for 48 hour.

  11. Combustion synthesis as a novel approach in preparation of polycrystalline Y{sub 2}Cu{sub 2}O{sub 5}

    Energy Technology Data Exchange (ETDEWEB)

    Gebrel, Z., E-mail: z_gebrel@yahoo.com; Blanusa, J.; Spasojevic, V.; Kusigerski, V.; Mrakovic, A.; Alqat, A.; Perovic, M.

    2013-08-15

    Highlights: •Y{sub 2}Cu{sub 2}O{sub 5} was successfully synthesized by both the glycine–nitrate and SHS method. •The reduction of synthesis duration down to 12 h has been achieved. •The detailed crystal structure and magnetic analyses of obtained material are provided. -- Abstract: Polycrystalline samples of Y{sub 2}Cu{sub 2}O{sub 5} were for the first time sintered from precursors obtained by two combustion routes – the glycine–nitrate method (sample S1) and a modified self-propagating high-temperature synthesis (sample S2). The detailed X-ray diffraction analysis has confirmed that both samples are well crystallized and single phase, with the high crystallization degree and cation ordering within a Cu sublattice. Magnetic characterization has shown magnetic behavior typical of pure Y{sub 2}Cu{sub 2}O{sub 5}. The distinctive advantages of these new synthesis routes in comparison to the ceramic sintering are in simplification of the overall procedure as well as in a significant reduction of synthesis duration from several days down to 31 h (S1) or 12 h (S2)

  12. Synthesis, characterization, crystal structure, and thermal analysis of 2-chloro-N-(1,5-dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazol-4-yl) acetamide

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, R. [University of Jammu, X-ray Crystallography Laboratory, Post-Graduate Department of Physics & Electronics (India); Nayak, P. S.; Narayana, B. [Mangalore University, Mangalagangotri, Department of Studies in Chemistry (India); Kant, R., E-mail: rkvk.paper11@gmail.com [University of Jammu, X-ray Crystallography Laboratory, Post-Graduate Department of Physics & Electronics (India)

    2015-12-15

    The title compound, C{sub 13}H{sub 14}O{sub 2}N{sub 3}Cl, has been synthesized by the reaction of chloroacetyl chloride with 4-aminoantipyrine in basic media and characterized by FT-IR, CHN elemental analysis, UV-Vis, TGA, DTA, DSC and single crystal X-ray diffraction. crystals are monoclinic, sp. gr. P2{sub 1}/c, a = 6.9994(6), b = 12.4035(13), c = 15.836(2) Å, β = 100.367(9)°, Z = 4. The crystal structure is stabilized by N–H···O and C–H···O interactions, the former interactions result in the formation of dimers corresponding to R{sub 2}{sup 2} (10) graphset motif and the dimers are further connected by C–H···O hydrogen bonding forming chains. In addition, the thermal stability of the compound was determined by TGA, DTA, DSC analysis, and absorption at λ{sub max} = 298 nm was determined by UV-Vis spectrophotometer.

  13. Synthesis of single crystal manganese oxide octahedral molecular sieve (OMS) nanostructures with tunable tunnels and shapes.

    Science.gov (United States)

    Li, Wei-Na; Yuan, Jikang; Gomez-Mower, Sinue; Sithambaram, Shantakumar; Suib, Steven L

    2006-02-23

    A new and facile route is reported to manipulate the self-assembly synthesis of hierarchically ordered Rb-OMS-2 and pyrolusite with an interesting flowerlike morphology by a direct and mild reaction between rubidium chromateand manganese sulfate without any organic templates. The crystal forms, morphologies, and tunnel sizes of the obtained OMS materials can be controlled. A mechanism for the growth of manganese dioxides with flowerlike architectures was proposed. The obtained products exhibit potential for use in catalysis and other applications.

  14. Rapid Synthesis and Characterization of Nano sodalite Synthesized using Rice Husk Ash

    International Nuclear Information System (INIS)

    Siti Haslina Ahmad Rusmili; Zainab Ramli

    2012-01-01

    Rice husk ash (RHA) which contains more than 90 percent silica is proven to be an active silica source in zeolite synthesis. In this study, nano sodalite has been successfully synthesized hydrothermally at 60 degree Celsius using RHA as silica source in alkaline medium at various crystallization times. Commercial fumed silica was used as comparison for the silica source. Analysis by XRD has shown that pure nano sodalite was formed in 3 hours and stable up to more than 24 hours when using RHA as silica source. On the other hand, fumed silica produced pure nano sodalite only at 4 hours while a mixture of zeolites was observed outside this time range. FESEM shows a worm-like morphology of nano sodalite in the size range of 50-100 nm while FTIR shows the formation of aluminosilicates bonds. Analysis on the dissolved silica in the gel reaction mixture demonstrates the decreasing mass of silica after prolong time of crystallization which indicates the consumption of the dissolved silica in crystal growth of nano sodalite. This study shows that RHA is a better silica source in stabilizing the nano sodalite phase in oxide gel reaction mixture as compared to fumed silica. (author)

  15. 2-nitrobenzohydrazide as a potent urease inhibitor: synthesis, characterization and single crystal x-ray diffraction analysis

    International Nuclear Information System (INIS)

    Abbas, N.; Khan, I.; Hameed, S.; Batool, S.

    2018-01-01

    2-Nitrobenzohydrazide was efficiently synthesized in two steps by the esterification of 2-nitrobenzoic acid followed by the treatment with hydrazine hydrate in methanol. The structure of 2-nitrobenzohydrazide was established by modern spectro-analytical techniques including FTIR, 1H and 13C-NMR spectroscopy and unequivocally confirmed by single crystal X-ray diffraction data. 2-Nitrobenzohydrazide crystallized in orthorhombic space group P 21 21 21 with unit cell dimensions a = 4.9764(4) Å, b = 12.5280 (3) Å, c = 12.8512(1) Å, α = β = γ = 90°. A combination of N‒H…N and N‒H…O hydrogen bonds stabilized the crystal packing of 3. The synthesized compound 3 was assessed as urease inhibitor against Jack bean urease and the results revealed good inhibitory potency with an IC50 value of 4.25 ± 0.08 µM. This inhibition strength was 5-fold higher compared to the reference inhibitor thiourea (IC50 = 21.00 ± 0.11 µM). The molecular docking studies of the synthesized inhibitor 3 inside the active pocket of urease revealed several important binding interactions. (author)

  16. Synthesis and characterization of the silver methacrylate and its polymerization with gamma radiation

    International Nuclear Information System (INIS)

    Figueroa de Paz, Y. M.

    2014-01-01

    One of the traditional objectives in research has been the development of new and useful materials that combine the properties of polymers with metals. Synthesis of monomers containing metal, followed by a polymerization process, is a method to introduce metal ions in the structure of a polymer, and the gamma radiation was easily applied to initiate polymerization. The coordination polymers have high insolubility, which is a general problem of these materials, besides the lack of structural information available. Also, due to the difficulty of obtaining single crystals, it has hindered the identification of the structures of some coordination polymers, requiring the use of indirect methods for structural characterization. In this work the synthesis of silver poly-methacrylate (PMAAg), was performed using the gamma radiation as polymerization initiator, having as precursor to silver methacrylate monomer (MAAg). The combination of spectroscopic methods revealed structural changes in the coordination polymers. With scanning electron microscopy, it was observed that the morphology of the monomer and its polymers is fiber, which grows with increasing radiation dose; furthermore, this increase in size is related to Bet analysis result, since the monomer has a bigger superficial area to the irradiated polymers. In monomer and irradiated polymers the crystalline structure CCC was observed by X-ray diffraction. By thermogravimetric analysis the decomposition temperature of the products was determined, finding around 150 degrees C. The infrared spectroscopy confirmed the silver methacrylate polymerization, as with increasing radiation dose, also increases the degree of polymerization; likewise the form of coordination of the monomer was determined and its irradiated polymers which corresponds to a bi-dentate chelate, confirmed by X-ray photoelectron spectroscopy. (Author)

  17. Transition metal borides. Synthesis, characterization and superconducting properties

    Energy Technology Data Exchange (ETDEWEB)

    Kayhan, Mehmet

    2013-07-12

    A systematic study was done on the synthesis and superconducting properties of metal rich transition metal borides. Five different binary systems were investigated including the boride systems of niobium, tantalum, molybdenum, tungsten and rhenium. High temperature solid state methods were used in order to synthesize samples of different transition metal borides of the composition M{sub 2}B, MB, M{sub 3}B{sub 2}, MB{sub 2}, and M{sub 2}B{sub 4}. The reactions were carried out in three different furnaces with different sample containers: the electric arc (copper crucible), the high frequency induction furnace (boron nitride, tantalum or glassy carbon crucibles), and the conventional tube furnace (sealed evacuated quartz ampoules). The products obtained were characterized with X-ray powder diffractometry, scanning electron microscopy and energy-dispersive X-ray spectroscopy. Phase analyses and crystal structure refinements using the Rietveld method and based on structure models known from literature were performed. A neutron diffraction measurement was done for W{sub 2}B{sub 4} to allow for a complete crystal structure determination, because of the presence of a heavy element like tungsten and a light element like boron that made it difficult to determine the accurate determination of the boron atom positions and occupancies from X-ray data. A new structure model for W{sub 2}B{sub 4} was proposed. Magnetic measurements in a SQUID magnetometer down to temperatures as low as 1.8 K were performed to several of the products in order to see if the transition metal borides become superconducting at low temperatures, and the results were compared with data from literature. Superconducting properties were found for the following compounds: NbB{sub 2} (T{sub C} = 3.5 K), β-MoB (T{sub C} = 2.4 K), β-WB (T{sub C} = 2.0 K), α-WB (T{sub C} = 4.3 K), W{sub 2}B{sub 4} (T{sub C} = 5.4 K), Re{sub 7}B{sub 3} (T{sub C} = 2.4 K). A relationship between the superconducting properties

  18. Synthesis, crystal growth and characterization of bioactive material: 2-amino-1H-benzo[d]imidazol-3-ium salicylate single crystal-a proton transfer molecular complex

    Science.gov (United States)

    Fathima, K. Saiadali; Anitha, K.

    2017-05-01

    The 1:1 molecular adducts 2-aminobenzimidazolium salicylate (ABIS) single crystal was synthesized and grown from 2-aminobenzimidazole (ABI) as a donor and salicylic acid (SA) as an acceptor. The cell parameter was determined using single crystal X-Ray diffraction method and the complex ABIS belongs to monoclinic system. The spectroscopic studies showed that ABIS crystal was an ion pair complex. The FTIR and Raman spectra showed that the presence of O-H, C=N, C=O vibration which confirms the proton transfer from SA to ABI. The UV-Vis spectrum exhibited a visible band at 359nm for ABIS due to the salicylate anion of the molecule. Further the antimicrobial activity of ABIS complex against Staphylococcus aureus, klebsiella pneumonia, Pseudomonas eruginos and E.coli pathogens was investigated. So the complex molecule inhibits both Gram positive and Gram negative bacterial. It is found that benzimidazole with aminogroup at position 2 increases the general antimicrobial activities of ABIS crystal.

  19. The Synthesis, Characterization and Catalytic Reaction Studies of Monodisperse Platinum Nanoparticles in Mesoporous Oxide Materials

    Energy Technology Data Exchange (ETDEWEB)

    Rioux, Robert M. [Univ. of California, Berkeley, CA (United States)

    2006-01-01

    A catalyst design program was implemented in which Pt nanoparticles, either of monodisperse size and/or shape were synthesized, characterized and studied in a number of hydrocarbon conversion reactions. The novel preparation of these materials enables exquisite control over their physical and chemical properties that could be controlled (and therefore rationally tuned) during synthesis. The ability to synthesize rather than prepare catalysts followed by thorough characterization enable accurate structure-function relationships to be elucidated. This thesis emphasizes all three aspects of catalyst design: synthesis, characterization and reactivity studies. The precise control of metal nanoparticle size, surface structure and composition may enable the development of highly active and selective heterogeneous catalysts.

  20. Synthesis and characterization of energetic thermoplastic elastomers for propellant formulations

    Directory of Open Access Journals (Sweden)

    Aparecida M. Kawamoto

    2009-01-01

    Full Text Available Synthesis and characterization of energetic ABA-type thermoplastic elastomers for propellant formulations has been carried out. Following the working plan elaborated, the synthesis and characterization of Poly 3- bromomethyl-3-methyl oxetane (PolyBrMMO, Poly 3- azidomethyl-3-methyl oxetane (PolyAMMO, Poly 3,3-bis-azidomethyl oxetane (PolyBAMO and Copolymer PolyBAMO/AMMO (by TDI end capping has been successfully performed. The thermoplastic elastomers (TPEs were synthesized using the chain elongation process PolyAMMO, GAP and PolyBAMO by diisocyanates. In this method 2.4-toluene diisocyanate (TDI is used to link block A (hard and mono- functional to B (soft and di-functional. For the hard A-block we used PolyBAMO and for the soft B-block we used PolyAMMO or GAP.This is a joint project set up, some years ago, between the Chemistry Division of the Institute of Aeronautics and Space (IAE - subordinated to the Brazilian Ministry of Defense - and the Fraunhofer Institut Chemische Technologie (ICT, in Germany. The products were characterized by different techniques as IR- and (1H,13CNMR spectroscopies, elemental and thermal analyses. New methodologies based on FT-IR analysis have been developed as an alternative for the determination of the molecular weight and CHNO content of the energetic polymers.

  1. Synthesis, crystal structures and luminescence properties of new multi-component co-crystals of isostructural Co(II) and Zn(II) complexes

    Science.gov (United States)

    Tella, Adedibu C.; Owalude, Samson O.; Omotoso, Mary F.; Olatunji, Sunday J.; Ogunlaja, Adeniyi S.; Alimi, Lukman O.; Popoola, Olugbenga K.; Bourne, Susan A.

    2018-04-01

    Two novel isostructural compounds containing multi-component co-crystals [M(C6H4NO2)2(H2O)2](C9H6O6)2 (M = Co (1), Zn (2), C6H4NO2 = Picolinic acid, C9H6O6 = Trimesic acid) have been synthesized. The compounds were characterized by elemental analysis, FT-IR, UV-Visible and 1H NMR spectroscopies as well as thermal and single crystal X-ray diffraction analyses. Single crystal X-ray diffraction analysis reveals that 1 and 2 are isostructural. Compound 1 crystallizes in triclinic space group (P-1, with a = 5.154 (10) Å, b = 11.125 (2) Å, c = 14.113 (3) Å, α = 91.01 (3)°, β = 100.54 (3)°, and γ = 102.71 (3)°). In a similar fashion, compound 2 crystallizes in triclinic space group (P-1, with a = 5.1735 (3) Å, b = 11.0930 (10) Å, c = 14.1554 (8) Å, α = 91.70 (3)°, β = 100.26 (3)°, γ = 102.90 (3)°). The metal (II) cation presents distorted MN2O4 octahedral geometry with H2O molecules coordinated to the metal in equatorial position while the picolinic acid molecules are axially coordinated through the pyridine N atom. The two trimesic acid molecules are not part of the first coordination sphere. Compounds 1 and 2 constitute an example of a class of coordination compound of multicomponent crystals having trimesic acid outside the coordination sphere where it is neither protonated or deprotonated. The two compounds were investigated for luminiscence properties.

  2. Particle size studies to reveal crystallization mechanisms of the metal organic framework HKUST-1 during sonochemical synthesis.

    Science.gov (United States)

    Armstrong, Mitchell R; Senthilnathan, Sethuraman; Balzer, Christopher J; Shan, Bohan; Chen, Liang; Mu, Bin

    2017-01-01

    Systematic studies of key operating parameters for the sonochemical synthesis of the metal organic framework (MOF) HKUST-1(also called CuBTC) were performed including reaction time, reactor volume, sonication amplitude, sonication tip size, solvent composition, and reactant concentrations analyzed through SEM particle size analysis. Trends in the particle size and size distributions show reproducible control of average particle sizes between 1 and 4μm. These results along with complementary studies in sonofragmentation and temperature control were conducted to compare these results to kinetic crystal growth models found in literature to develop a plausible hypothetical mechanism for ultrasound-assisted growth of metal-organic-frameworks composed of a competitive mechanism including constructive solid-on-solid (SOS) crystal growth and a deconstructive sonofragmentation. Copyright © 2016 Elsevier B.V. All rights reserved.

  3. Synthesis and Characterization of Poly(Amidoamine Dendrimers Encapsulatd 198Au Nanoparticles

    Directory of Open Access Journals (Sweden)

    R. Ritawidya1,2

    2012-12-01

    Full Text Available Brachytherapy or internal radiotherapy is one of many methods used for treatment of cancer. This modality requires an agent with radionuclides that emits  or β particle with a proper energy. 198Au (99% β max = 0.96 MeV and t1/2 = 2.69 days is one of radionuclides that has been considered to be effective for the above-mentioned purpose. The purpose of this research was to synthesis and characterize poly(amidoamine (PAMAM G3.0 dendrimers encapsulated 198Au nanoparticles as a new brachytherapy agent. PAMAM G3.0 dendrimers encapsulated 198Au nanoparticles was successfully synthesized by a bottom-up method using sodium borohydride as a reductor. Purification was then performed by a size exclusion chromatography in order to separate large Au nanoparticles that were formed outside the cavity of PAMAM G3.0 dendrimers. Prior to the synthesis of PAMAM G3.0 dendrimers encapsulated 198Au nanoparticles, the synthetic procedure was first established by using a non-radioactive Au. The PAMAM G3.0 dendrimers encapsulated Au nanoparticles produced was then characterized by using an UV-Vis spectroscopy, a transmission electron microscopy (TEM, particle size analyzer (PSA, and an atomic absorption spectroscopy (AAS. Characterization results revealed that PAMAM G3.0 dendrimers encapsulated Au nanoparticles that were prepared from a reaction mixture of PAMAM G3.0 dendrimers and Au HAuCl4 with mol ratio of 2.8, was found to be a proper formula. It produced PAMAM G3.0 dendrimers encapsulated Au nanoparticles with diameter of 1.743 nm, spheris, uniform and drug loading value of 26.34%. This formula was then used in synthesis using radioactive Au, 198Au. Characterization results of PAMAM G3.0 dendrimers encapsulated 198Au nanoparticles gave a radiochemical purity of 99.4% and zero charge.

  4. Synthesis, characterization, and reactivity of furan- and thiophene-functionalized bis(n-heterocyclic carbene) complexes of iron(II)

    KAUST Repository

    Rieb, Julia

    2014-09-15

    The synthesis of iron(II) complexes bearing new heteroatom-functionalized methylene-bridged bis(N-heterocyclic carbene) ligands is reported. All complexes are characterized by single-crystal X-ray diffraction (SC-XRD), nuclear magnetic resonance (NMR) spectroscopy, and elemental analysis. Tetrakis(acetonitrile)-cis-[bis(o-imidazol-2-ylidenefuran)methane]iron(II) hexafluorophosphate (2a) and tetrakis(acetonitrile)-cis-[bis(o-imidazol-2-ylidenethiophene)methane]iron(II) hexafluorophosphate (2b) were obtained by aminolysis of [Fe{N(SiMe3)2}2(THF)] with furan- and thiophene-functionalized bis(imidazolium) salts 1a and 1b in acetonitrile. The SC-XRD structures of 2a and 2b show coordination of the bis(carbene) ligand in a bidentate fashion instead of a possible tetradentate coordination. The four other coordination sites of these distorted octahedral complexes are occupied by acetonitrile ligands. Crystallization of 2a in an acetone solution by the slow diffusion of Et2O led to the formation of cisdiacetonitriledi[ bis(o-imidazol-2-ylidenefuran)methane]iron(II) hexafluorophosphate (3a) with two bis(carbene) ligands coordinated in a bidentate manner and two cis-positioned acetonitrile molecules. Compounds 2a and 2b are the first reported iron(II) carbene complexes with four coordination sites occupied by solvent molecules, and it was demonstrated that those solvent ligands can undergo ligand-exchange reactions.

  5. Crystal habit dependent quantum confined photoluminescence of zinc oxide nanostructures

    International Nuclear Information System (INIS)

    Arellano, Ian Harvey J.; Payawan, Leon Jr. M.; Sarmago, Roland V.

    2008-01-01

    Diverse zinc oxide crystal habits namely wire, rods, tubes, whiskers and tetrapods were synthesized via hydrothermal and carbothermal reduction routes. A vapor current induced regionalization in the carbothermal synthesis lead to the isolation of these crystal habits for characterization. The surface morphology of the nanostructures was analyzed via field emission scanning electron microscopy (FESEM). The morphology and crystallinity of the as-synthesized nanostructure architectural motifs were related to their photoluminescence (PL). The photoluminescence at 157 nm was taken using F2 excimer laser and a crystal habit dependent response was observed. X-ray diffraction (XRD) analyses were conducted to deduce the degree of crystallinity showing results consistent with the excitonic emission at the band edge and visible emission at the electron-hole recombination sites. The presence of minimal crystal defects which gave the green emission was supported by energy dispersive spectroscopy (EDS) data. Transmission spectroscopy for the tetrapods exhibited an interesting PL reduction associated with high-energy deep traps in the nanostructures. Furthermore, some intensity dependent characteristics were deduced indicating quantum confined properties of these nano structures. (author)

  6. Synthesis and X-ray crystal structure of the first tetrathiafulvalene-based acceptor-donor-acceptor sandwich

    DEFF Research Database (Denmark)

    Simonsen, Klaus B.; Thorup, Niels; Cava, Michael P.

    1998-01-01

    The synthesis and characterization of a bis-macrocyclic A-D-A sandwich produced in a simple one-pot reaction is reported. Only one acceptor unit participates in charge-transfer interactions with the TTF unit in the solid state....

  7. Synthesis and characterization of dental composites

    Science.gov (United States)

    Djustiana, Nina; Greviana, Nadia; Faza, Yanwar; Sunarso

    2018-02-01

    During the last few decades, the increasing demands in esthetic dentistry have led to the development of dental composites material that provide similar appearance to the natural teeth. Recently, esthetic trend was an issue which increase the demand for teeth restorations that is similar with the origin. The esthetics of dental composite are more superior compared to amalgam, since its color look similar with natural teeth. Various dental composites have been developed using many type of fillers such as amorphous silica, quartz), borosilicate, Li-Sr-Ba-Al glass and oxide: zirconia and alumina. Researchers in Faculty of Dentistry University of Padjadjaran have prepared dental composites using zirconia-alumina-silica (ZAS) system as the filler. The aim is to improve the mechanical properties and the esthetic of the dental composites. The ZAS was obtained from chemical grade purity chemicals and Indonesia's natural sand as precursors its characterization were also presented. This novel method covers the procedure to synthesis and characterize dental composites in Padjadjaran University and some review about dental composites in global research.

  8. Thermotropic Ionic Liquid Crystals

    Science.gov (United States)

    Axenov, Kirill V.; Laschat, Sabine

    2011-01-01

    The last five years’ achievements in the synthesis and investigation of thermotropic ionic liquid crystals are reviewed. The present review describes the mesomorphic properties displayed by organic, as well as metal-containing ionic mesogens. In addition, a short overview on the ionic polymer and self-assembled liquid crystals is given. Potential and actual applications of ionic mesogens are also discussed. PMID:28879986

  9. Thermotropic Ionic Liquid Crystals

    Directory of Open Access Journals (Sweden)

    Sabine Laschat

    2011-01-01

    Full Text Available The last five years’ achievements in the synthesis and investigation of thermotropic ionic liquid crystals are reviewed. The present review describes the mesomorphic properties displayed by organic, as well as metal-containing ionic mesogens. In addition, a short overview on the ionic polymer and self-assembled liquid crystals is given. Potential and actual applications of ionic mesogens are also discussed.

  10. Thermotropic Ionic Liquid Crystals.

    Science.gov (United States)

    Axenov, Kirill V; Laschat, Sabine

    2011-01-14

    The last five years' achievements in the synthesis and investigation of thermotropic ionic liquid crystals are reviewed. The present review describes the mesomorphic properties displayed by organic, as well as metal-containing ionic mesogens. In addition, a short overview on the ionic polymer and self-assembled liquid crystals is given. Potential and actual applications of ionic mesogens are also discussed.

  11. Thermotropic Ionic Liquid Crystals

    OpenAIRE

    Axenov, Kirill V.; Laschat, Sabine

    2011-01-01

    The last five years’ achievements in the synthesis and investigation of thermotropic ionic liquid crystals are reviewed. The present review describes the mesomorphic properties displayed by organic, as well as metal-containing ionic mesogens. In addition, a short overview on the ionic polymer and self-assembled liquid crystals is given. Potential and actual applications of ionic mesogens are also discussed.

  12. Single crystalline Co3O4: Synthesis and optical properties

    International Nuclear Information System (INIS)

    Hosny, Nasser Mohammed

    2014-01-01

    Crystals of Co 3 O 4 have been prepared from thermal decomposition of molecular precursors derived from salicylic acid and cobalt (II) acetate or chloride at 500 °C. A cubic phase Co 3 O 4 micro- and nanocrystals have been obtained. The as-synthesized products were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM) and transmission electron microscope (TEM). The images of electron microscopes showed octahedral crystals of Co 3 O 4 . The volume and polarizability of the optimized structures of molecular precursors have been calculated and related to the particle size. The optical band gap of the obtained crystals has been measured. The results indicated two optical band gaps with values 2.65 and 2.95 eV for (E g1 ) (E g2 ), respectively. - Highlights: • Synthesis of Co 3 O 4 nanocrystals by decomposition of cobalt salicylic acid precursor. • Characterization of the isolated nanocrystals by using XRD, SEM and HRTEM. • The optical band gap has been measured

  13. Synthesis of porous CuInS2 crystals

    International Nuclear Information System (INIS)

    Akaki, Yoji; Matsubara, Takanori; Ohno, Yuki; Momiki, Takanori; Ide, Kazuki

    2009-01-01

    CuInS 2 crystals were grown from starting materials CuCl 2 .2H 2 O, InCl 3 .4H 2 O and thiourea with ethylene glycol solution, that were placed into a flask, heated, and refluxed for 1 hour. The diffraction peaks only from CuInS 2 phase appear for all the samples. The morphology of CuInS 2 crystal was porous, and the porous crystals exist in two kinds. One kind was flower-like crystals which complexly lack the flakes, another one was sphere-like crystals existed with a number of the poles. The sizes of sphere-like porous crystals were approximately 1.0 μm. The specific surface area of the samples grown at 180 C and 600 rpm estimated approximately 30 m 2 /g. (copyright 2009 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  14. Synthesis, characterization and gas sensing performance of SnO2 ...

    Indian Academy of Sciences (India)

    Synthesis, characterization and gas sensing performance of SnO2 thin films prepared by spray pyrolysis. GANESH E PATIL, D D KAJALE, D N CHAVAN†, N K PAWAR††, P T AHIRE, S D SHINDE#,. V B GAIKWAD# and G H JAIN. ∗. Materials Research Laboratory, Arts, Commerce and Science College, Nandgaon 423 106, ...

  15. The effect of Cu{sup II} ions in L-asparagine single crystals

    Energy Technology Data Exchange (ETDEWEB)

    Santana, Ricardo C., E-mail: santana@ufg.br; Gontijo, Henrique O.; Menezes, Arthur F.; Martins, José A.; Carvalho, Jesiel F., E-mail: carvalho@ufg.br

    2016-11-15

    We report the synthesis, crystal growth, and spectroscopic characterization of L-asparagine monohydrate (LAM) single crystals doped with CuII. The crystals were successfully grown by slow cooling from a supersaturated aqueous solution up to size of 16×12×2 mm{sup 3};the effect of copper impurities in the crystals morphology was discussed. Electron Paramagnetic Resonance (EPR) was used to calculate the g and hyperfine coupling (A) tensors of the CuII ions (g{sub 1}=2.044, g{sub 2}=2.105, g{sub 3}=2.383and A{sub 1}≈0, A{sub 2}=35, A{sub 3}=108 Gauss). The EPR spectra for certain orientations of the magnetic field suggest that CuII ions are coordinated to two {sup 14}N atoms. Correlating the EPR and optical absorption results, the crystal field and the Cu{sup II} orbital bond parameters were calculated. The results indicate that the paramagnetic center occupies interstitial rhombic distorted site and the ground orbital state for the unpaired electron is the d(x{sup 2}-y{sup 2}).

  16. Hydrothermal synthesis of silica rich zeolites and microporous martials

    International Nuclear Information System (INIS)

    Durrani, S.K.; Chughtai, N.A.; Akhtar, J.; Arif, M.; Ahmed, M.

    1999-01-01

    A fast crystallization method for synthesis of silica rich aluminosilicate and ferro silicate zeotype materials has been reported. The method also permits for the complete crystallization of silico alumino phosphate microporous materials. Aluminosilicate and ferro silicate silica rich zeotype materials and silico alumino phosphate microporous materials have been synthesized from the reaction mixture of colloidal silica sol, reactive aluminum, ferrous and phosphorous salts, and the essential organic templates at 373-473 K and were characterized by TG/DTA/DSC, X-ray diffraction, scanning electron microscopy and other analytical techniques. Crystallinity and unit cell parameters of the synthesized materials were found to be the function of Al and Fe content of zeolites. (author)

  17. Synthesis, Crystal Structure of a Novel Mn Complex with Nicotinoyl-Glycine

    Directory of Open Access Journals (Sweden)

    Xin Wang

    2016-12-01

    Full Text Available A novel manganese complex, C16H26MnN4O12, was synthesized by the reaction of nicotinoyl-glycine and NaOH in an ethanol/water solution and structurally characterized by elemental analysis, UV-vis spectrum, IR spectrum and single-crystal X-ray diffraction analysis. The crystal of the complex belongs to the triclinic space group P1 with a = 7.8192(16 Å, b = 8.8800(18 Å, c = 9.0142(18 Å, α = 83.14(3°, β = 65.27(3°, γ = 81.67(3°, V = 516.3(2 Å3, Z = 1, Dx = 1.542 mg·m−3, μ = 0.66 mm−1, F(000 = 271, and final R1 = 0.0381, ωR2 = 0.0964. The nicotinoyl-glycine ligand acts as a bridging ligand to connect the manganese ions by the hydrogen interactions; thus, the complex expands into a 3D supramolecular net structure.

  18. Materials Research Society Symposium Proceedings Volume 635. Anisotropic Nanoparticles - Synthesis, Characterization and Applications

    National Research Council Canada - National Science Library

    Lyon, L

    2000-01-01

    This volume contains a series of papers originally presented at Symposium C, "Anisotropic Nanoparticles Synthesis, Characterization and Applications," at the 2000 MRS Fall Meeting in Boston, Massachusetts...

  19. Effect of the raw material type and the reaction time on the synthesis of halloysite based Zeolite Na-P1

    Directory of Open Access Journals (Sweden)

    Mahdi Meftah

    Full Text Available Zeolites are currently one of the most important classes of inorganic materials because of their multiple applications not only as ions exchangers and molecular sieves, but also as catalysts. This works focus the synthesis and the characterization of Zeolite Na-P1 using halloysite (collected near Ain Khemouda, western Tunisia as the starting material. Two parameters, such as the host materials type (natural or treated and the reaction time, involved in the synthesis process are investigated. The intermediate phases and final products were characterized by X-ray diffraction, Infrared IR spectroscopy, scanning electron microscopy and high-resolution 29Si and 27Al MAS NMR. Obtained results show that the hydrothermal synthesis from natural and heated-halloysite leads to formation of homogenous Zeolite Na-P1. The difference in the crystallization/transformation time process is explained by the effect of the dissolution rate of the starting materials in sodium hydroxide solution. In the case of heated halloysite, the synthesis reaction with alkali solution occurs very readily and achieved without prior thermal activation at high temperature. The optimal conditions of Zeolite Na-P1 crystallization, from heated-halloysite, are reached at 120 °C. Keywords: Zeolite Na-P1, Halloysite, X-ray, FTIR spectroscopy, SEM, 29Si and 27Al MAS NMR spectroscopy

  20. Synthesis and characterization of new oxides and oxynitrides of niobium; Synthese und Charakterisierung neuer Oxide und Oxidnitride des Niobs

    Energy Technology Data Exchange (ETDEWEB)

    Orthmann, Steven

    2017-11-02

    By different synthesis routes the first oxide nitrides in the series scandium-niobium-oxygen-nitrogen could be synthesized and characterized. ScNb{sub 4}O{sub 7}N{sub 3}, which crystallizes in the rutile-type structure, exhibit a band gap of 2.62 eV after a short oxidation. Furthermore anion-deficit NbSc{sub 2}(O,N,□){sub 6} with fluorite-type structure could be synthesized. UV-Vis measurements point to a band gap of 3.36 eV after a short oxidation of the product. In the series zirconium-niobium-oxygen-nitrogen new oxides and oxide nitrides could be synthesized. By replacing zirconium with hafnium isotopical compounds with comparable composition could be obtained. The crystal structure of these new compounds is discussed respecting magnetism and the results of electron microscopy and neutron diffraction. By partially substitution of niobium with magnesium or zinc three additional oxide nitrides with the compositions Mg{sub 2}Nb{sub 4}O{sub 2}N{sub 5}, Zn{sub 2}NbO{sub 0,3}N{sub 2,8}, and ZnNb{sub 3}O{sub 0,1}N{sub 4,5}, showing a tetragonal Nb{sub 4}N{sub 5}-type structure, could be synthesized.

  1. Characterization of gypsum crystals exposed to a high CO2 concentration fog using x-ray

    International Nuclear Information System (INIS)

    Carreño-Márquez, I. J. A.; Castillo-Sandoval, I.; Esparza-Ponce, H. E.; Fuentes-Cobas, L.; Montero-Cabrera, M. E.

    2015-01-01

    In Chihuahua State, a little town called Naica has the largest gypsum single crystals in the world. The growth of these structures has been described as a long and stable process developed over thousands of years. Due to the change in the environmental conditions, these crystals could suffer alterations on their surface. In this project we study the cause of possible deterioration of the giant crystals and intend to suggest measures for their preservation. For this sake, our first experiment consists on several gypsum crystals that have been subjected in a climate chamber to a fog at high CO 2 concentration and 51 °C for a period of time of six months, extracting two crystals every 15 days. Then the crystals have been characterized through Grazing Incidence X-Ray Diffraction using a diffractometer PanAlytical X’PertPro with two different detectors; Xe-filled proportional detector and a Pixel 3D detector. The results were compared to determine which technique is the most suitable to study the degradation of gypsum single crystals. In the two cases, we have identified only the gypsum phase, but with different crystal plane orientations

  2. SECCOX, a novel x-ray characterization bench for Bragg crystals and x-rays optics

    International Nuclear Information System (INIS)

    Caillaud, T.; Manson, M.; Desenne, D.; Goze, B.; Rivet, A.; Derouineau, Ph.

    2007-01-01

    Laser programs require the use of a large number of calibrated x-ray crystals implemented inside spectrometers and microscopes used in diagnostics. In this context, a new apparatus was designed in collaboration with CELIA laboratory, Saint-Gobain Crystals and Detectors and CEA to characterize x-ray Bragg crystals. Station d'Etude et de Caracterisation des Cristaux pour les Optiques X (SECCOX) is based on a micrometric x-ray source and an automated spectrometer equipped with a CCD camera. Properties such as homogeneity, resolution, radius of curvature and reflectivity are measured to guarantee diagnostic performance in laser-plasma physics experiments. We will present the experimental device, techniques and results of the calibration obtained. (authors)

  3. Nano-/micro metallic wire synthesis on Si substrate and their characterization

    International Nuclear Information System (INIS)

    Kaur, Jaskiran; Kaur, Harmanmeet; Singh, Surinder; Kanjilal, Dinakar; Chakarvarti, Shiv Kumar

    2014-01-01

    Nano-/micro wires of copper are grown on semiconducting Si substrate using the template method. It involves the irradiation of 8 um thick polymeric layer coated on Si with150 MeV Ni ion beam at a fluence of 2E8. Later, by using the simple technique of electrodeposition, copper nano-/micro wires were grown via template synthesis. Synthesized wires were morphologically characterized using SEM and electrical characterization was carried out by finding I-V plot

  4. Synthesis and characterization of Mg-doped ZnO hollow spheres

    International Nuclear Information System (INIS)

    Hammad, Talaat M.; Salem, Jamil K.

    2011-01-01

    Mg-doped ZnO nanoparticles were synthesized by a simple chemical method at low temperature with Mg:Zn atomic ratio from 0 to 7%. The synthesis process is based on the hydrolysis of zinc acetate dihydrate and magnesium acetate tetrahydrate were heated under refluxing at 65 °C using methanol as a solvent. X-ray diffraction analysis reveals that the Mg-doped ZnO crystallizes in a wurtzite structure with crystal size of 5–12 nm. These nanocrystals self-aggregated themselves into hollow spheres of size of 800–1100 nm. High resolution transmission electron microscopy images show that each sphere is made up of numerous nanoparticles of average diameter 5–11 nm. The XRD patterns, SEM and TEM micrographs of doping of Mg in ZnO confirmed the formation of hollow spheres indicating that the Mg 2+ is successfully substituted into the ZnO host structure of the Zn 2+ site. Furthermore, the UV–Vis spectra and photoluminescence (PL) spectra of the ZnO nanoparticles were also investigated. The band gap of the nanoparticles can be tuned in the range of 3.36–3.55 eV by the use of the dopants.

  5. Synthesis and Characterization of Nanostructured Nickel Diselenide NiSe2 from the Decomposition of Nickel Acetate, (CH3CO22Ni

    Directory of Open Access Journals (Sweden)

    Ming Yin

    2014-01-01

    Full Text Available Solution processed NiSe2 nanorods were synthesized by a modified colloidal synthesis technique, by chemical reaction of TOPSe and nickel acetate at 150°C. The rods exist as an oleic acid ligand stabilized solution, with oleic acid acting as a capping group. Structural characterization by X-ray diffraction and transmission electron microscopy indicates that the particles are rod-like shaped crystals with a high and relatively constant aspect ratio (30 : 1. TEM shows that the width and the length of the nanorods are in the range 10–20 nm and 300–350 nm, respectively. XRD indicates that the nanorods are pure and well crystallized. The size of nanorods based on the Debye-Scherrer effect, was 150 nm, the average value of length and width. They display thermal stability over prolonged heating times (<100 hours at 150°C, for which the average particle size is roughly constant. After about 100 hours of heating time there is an onset and growth of micron sized cubes and concurrent decomposition of NiSe2 to Ni and NiSe at 150°C.

  6. Synthesis, structure, growth and characterization of a novel organic NLO single crystal: Morpholin-4-ium p-aminobenzoate

    International Nuclear Information System (INIS)

    Shanmugam, G.; Ravi Kumar, K.; Sridhar, B.; Brahadeeswaran, S.

    2012-01-01

    Highlights: ► A new organic NLO crystal morpholin-4-ium p-aminobenzoate has been grown for the first time. ► The structure is reported for the first time in the literature. ► Thermal, optical and SHG studies suggest its suitability for various NLO applications. -- Abstract: The title compound, morpholin-4-ium p-aminobenzoate (MPABA)(C 4 H 10 NO + ,C 7 H 6 NO 2 − ), has been synthesized for the first time by the addition of morpholine with 4-aminobenzoic acid in equi-molar ratio and good quality single crystals have been grown by solution growth technique using methanol as a solvent. The molecular structure of the compound was solved and refined by Direct Methods using SHELXS97 and full-matrix least-squares technique using SHELXL97, respectively. MPABA crystallizes in a monoclinic system with unit cell parameters, a = 5.948(5) Å, b = 18.033(4) Å, c = 10.577(5) Å, β = 90.40(1)° and non-centrosymmetric space group Cc. The experimentally measured density and chemical compositions were found to be in good agreement with the theoretical values. The phases and functional groups of MPABA have been identified and confirmed through powder X-ray diffraction and Fourier transform infrared (FTIR) studies, respectively. The thermal stability and decomposition details were studied through TG/DTA thermograms. The UV–visible transmission spectra were recorded for the grown crystal and its NLO characteristic was explored by powder second harmonic generation (SHG) studies.

  7. Synthesis, crystal structure refinement, and nonlinear-optical properties of CaB{sub 3}O{sub 5}(OH): Comparative crystal chemistry of calcium triborates

    Energy Technology Data Exchange (ETDEWEB)

    Yamnova, N. A., E-mail: aks.crys@gmail.com; Aksenov, S. M. [Moscow State University, Faculty of Geology (Russian Federation); Stefanovich, S. Yu. [Moscow State University, Faculty of Chemistry (Russian Federation); Volkov, A. S.; Dimitrova, O. V. [Moscow State University, Faculty of Geology (Russian Federation)

    2015-09-15

    Calcium triborate CaB{sub 3}O5(OH) obtained by hydrothermal synthesis in the Ca(OH){sub 2}–H{sub 3}BO{sub 3}–Na{sub 2}CO{sub 3}–KCl system is studied by single-crystal X-ray diffraction. The parameters of the orthorhombic unit cell are as follows: a = 13.490(1), b = 6.9576(3), and c = 4.3930(2) Å; V = 412.32(3) Å{sup 3} and space group Pna2{sub 1}. The structure is refined in the anisotropic approximation of the atomic displacement parameters to R = 4.28% using 972 vertical bar F vertical bar > 4σ(F). It is confirmed that the crystal structure of Ca triborate CaB{sub 3}O{sub 5}(OH) is identical to that described earlier. The hydrogen atom is localized. An SHG signal stronger than that of the quartz standard is registered. The phase transition of calcium triborate into calciborite is found on heating. The comparative crystal-chemical analysis of a series of borates with the general chemical formula 2CaO · 3B{sub 2}O{sub 3} · nH{sub 2}O (n = 0–13) with the constant CaO: B{sub 2}O{sub 3}= 2: 3 ratio and variable content of water is performed.

  8. Green mediated synthesis and characterization of ZnO nanoparticles using Euphorbia Jatropa latex as reducing agent

    Directory of Open Access Journals (Sweden)

    M.S. Geetha

    2016-09-01

    Full Text Available Presently the progress of green chemistry in the synthesis of nanoparticles with the use of plants has engrossed a great attention. This study reports the synthesis of ZnO using latex of Euphorbia Jatropa as reducing agent. As prepared product was characterized by powder X-ray diffractometer (PXRD, Fourier transform infra-red spectroscopy (FTIR, scanning electron microscopy–energy dispersive spectroscopy (SEM–EDS, transmission electron microscopy (TEM, X-ray photo electron spectroscopy (XPS, Rietveld refinement, UV–Visible spectroscopy and photoluminescence (PL. The concentration of plant latex plays an important role in controlling the size of the particle and its morphology. PXRD graphs showed the well crystallisation of the particles. The average particle size was calculated using Scherrer equation and advanced Williamson Hall (WH plots. The average particle size was around 15 nm. This result was also supported by SEM and TEM analyses. FTIR shows the characteristic peak of ZnO at 435 cm−1. SEM and TEM micrographs show that the particles were almost hexagonal in nature. EDS of SEM analysis confirmed that the elements are only Zn and O. EDS confirmed purity of ZnO. Atomic states were confirmed by XPS results. Crystal parameters were determined using Rietveld refinement. From UV–Visible spectra average energy gap was calculated which is ∼3.63 eV. PL studies showed UV emission peak at 392 nm and broad band visible emission centred in the range 500–600 nm. The Commission International de I'Eclairage and colour correlated temperature coordinates were estimated for ZnO prepared using 2 ml, 4 ml and 6 ml Jatropa latex. The results indicate that the phosphor may be suitable for white light emitting diode (WLED. The study fruitfully reveals simple, fast, economical and eco friendly method of synthesis of multifunctional ZnO nanoparticles (Nps.

  9. Synthesis and characterization of poly aniline for electrochemical biosensor construction

    International Nuclear Information System (INIS)

    Magalhaes, Gleice S.L.; Southgate, Erica F.; Alhadeff, Eliana M.; Guimaraes, Maria Jose O.C.

    2011-01-01

    Conductors polymers have many attractive interests to the industry due their highly technological applications. This work treats specially of polyaniline because it's large electrical conductivity, electrochemical properties, associate to the chemical stability in environmental conditions and synthesis facility. The main of this work is the application in a construction of an electrochemical biosensor for ethanol detection and quantification. Different conditions of synthesis of the conductor emeraldine polyaniline form were studied, investigated the influence of the dopant agent and the reactional environment conditions temperature on the reaction yield and conductivities. The polyaniline that showed the best conductivity were characterized by differential and thermal gravimetric analysis, infrared spectroscopy, X ray diffraction, and cycle voltammetry, comparing with the commercial polyaniline. (author)

  10. Solid dispersions of Myricetin with enhanced solubility: Formulation, characterization and crystal structure of stability-impeding Myricetin monohydrate crystals

    Science.gov (United States)

    Mureşan-Pop, M.; Pop, M. M.; Borodi, G.; Todea, M.; Nagy-Simon, T.; Simon, S.

    2017-08-01

    Three solid dispersion forms of Myricetin combined with the Polyvinylpyrrolidone were successfully prepared by spray drying method, and characterized by X-ray powder diffraction, thermal analysis, infrared spectroscopy and optical microscopy. Zeta potential measurements provided indications on solid dispersions stability in aqueous suspension related to their storage at elevated temperature and relative humidity, which depends on the Myricetin load. By increase of Myricetin load, the stability of the solid dispersion is impeded due to growth of Myricetin monohydrate crystals. The amorphous dispersions with 10% and 50% Myricetin load are stable and, compared to pure Myricetin, their aqueous solubility is enhanced by a factor of 47 and 13, respectively. The dispersion with 80% Myricetin load is unstable on storage, and this behavior acts in conjunction with the development of Myricetin monohydrate crystals. Single-crystal X-ray diffraction results obtained for Myricetin monohydrate reveal a structure of an infinite 2D network of hydrogen-bonded molecules involving all six hydroxyl groups of Myricetin. The water molecules are positioned in between the infinite chains, and contribute via H-bonds to robust crystal packing. The calculated needle-like morphology of monohydrate form is in agreement with the optical microscopy results. The study shows that the solid amorphous dispersions with up to 50% Myricetin load are a viable option for achieving substantial solubility improvement of Myricetin, and supports their potential use in pharmaceutical applications.

  11. Synthesis and characterization of Au incorporated Alq3 nanowires

    Science.gov (United States)

    Khan, Mohammad Bilal; Ahmad, Sultan; Parwaz, M.; Rahul, Khan, Zishan H.

    2018-05-01

    We report the synthesis and characterization of pure and Au incorporated Alq3 nanowires. These nanowires are synthesized using thermal vapor transport method. The luminescence intensity of Au incorporated Alq3 nanowires are recorded to be higher than that of pure Alq3 nanowires, which is found to increase with the increase in Au concentration. Fluorescence quenching is also observed when Au concentration is increased beyond the certain limit.

  12. Synthesis and Characterization of Highly Intercalated Graphite Bisulfate

    Science.gov (United States)

    Salvatore, Marcella; Carotenuto, Gianfranco; De Nicola, Sergio; Camerlingo, Carlo; Ambrogi, Veronica; Carfagna, Cosimo

    2017-03-01

    Different chemical formulations for the synthesis of highly intercalated graphite bisulfate have been tested. In particular, nitric acid, potassium nitrate, potassium dichromate, potassium permanganate, sodium periodate, sodium chlorate, and hydrogen peroxide have been used in this synthesis scheme as the auxiliary reagent (oxidizing agent). In order to evaluate the presence of delamination, and pre-expansion phenomena, and the achieved intercalation degree in the prepared samples, the obtained graphite intercalation compounds have been characterized by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray powder diffraction (XRD), infrared spectroscopy (FT-IR), micro-Raman spectroscopy ( μ-RS), and thermal analysis (TGA). Delamination and pre-expansion phenomena were observed only for nitric acid, sodium chlorate, and hydrogen peroxide, while the presence of strong oxidizers (KMnO4, K2Cr2O7) led to stable graphite intercalation compounds. The largest content of intercalated bisulfate is achieved in the intercalated compounds obtained from NaIO4 and NaClO3.

  13. Synthesis and characterization of the mixed ligand coordination polymer CPO-5

    International Nuclear Information System (INIS)

    Kongshaug, K.O.; FjellvAg, Helmer

    2003-01-01

    The synthesis and crystal structures of a novel coordination polymer and its high-temperature variant are described. The as-synthesized material (CPO-5-as), of composition Zn(4,4'-bipyridine)(4,4'-biphenyldicarboxylate)·3H 2 O, crystallizes in the triclinic space group P-1 (No. 2) with a=11.0197(2), b=14.2975(3), c=7.6586(1) A, α=95.9760(9) deg. , β=108.026(1) deg. , γ=91.373(1) deg. and V=1139.16(4) A 3 . CPO-5-as is composed of tetrahedral zinc centers that are connected by the organic linkers to give five independent, interpenetrating diamond networks. In the structure, there is additional space for channels that are filled with three water molecules. These water molecules can be removed, leading to an anhydrous variant at 130 o C. CPO-5-130, of composition Zn(4,4'-bipyridine)(4,4'-biphenyldicarboxylate), crystallizes in the triclinic space group P-1 (No. 2) with a=11.1844(6), b=14.0497(7), c=7.7198(3) A, α=96.917(2) deg. , β=109.527(2) deg. , γ=89.115(3) deg. and V=1134.6(1) A 3 . The structure of the five interpenetrating networks is virtually unchanged after the dehydration resulting in CPO-5-130 being a porous structure with an estimated free volume of 19.8%

  14. Crystallization, characterization and preliminary X-ray crystallographic analysis of GK2848, a putative carbonic anhydrase of Geobacillus kaustophilus

    International Nuclear Information System (INIS)

    Ragunathan, Preethi; Raghunath, Gokul; Kuramitsu, Seiki; Yokoyama, Shigeyuki; Kumarevel, Thirumananseri; Ponnuraj, Karthe

    2013-01-01

    The expression, purification, characterization and crystallization of GK2848, a carbonic anhydrase from G. kaustophilus, are described. The crystals diffracted to a resolution of 2.70 Å. GK2848, a hypothetical protein from the thermophilic organism Geobacillus kaustophilus, was cloned and overexpressed in Escherichia coli. The protein was purified to homogeneity using Ni–NTA affinity-column and gel-filtration chromatography. The purified protein was crystallized using the sitting-drop vapour-diffusion method. The crystals diffracted to a resolution of 2.70 Å and belonged to the orthorhombic space group P2 1 2 1 2. GK2848 bears sequence homology to carbonic anhydrases of various bacterial species, indicating that it belongs to the carbonic anhydrase family of proteins. A subsequent carbonic anhydrase activity assay of GK2848 using the Wilbur–Anderson method confirmed its function as a carbonic anhydrase. A preliminary structure solution was obtained by molecular replacement using MOLREP. Mutation and biochemical characterization of the protein are in progress. The structure and functional analysis of GK2848 might provide valuable information on a novel class of carbonic anhydrases, as none of its homologous structures have been characterized

  15. 5-Arylidene derivatives of Meldrum's acid: Synthesis, structural characterization using single crystal and powder crystal X-ray diffraction, and electronic properties

    Science.gov (United States)

    Dey, Tanusri; Ghosh, Soumen; Ghosh, Somnath; Mukherjee, Alok Kumar

    2015-07-01

    Four 5-arylidene derivatives of Meldrum's acid, 5-(4-chlorobenzylidene)-2,2-dimethyl-1,3-dioxane-4,6-dione (2), 5-(3-hydroxybenzylidene)-2,2-dimethyl-1,3-dioxane-4,6-dione (3), 5-(3,4-dimethoxybenzylidene)-2,2-dimethyl-1,3-dioxane-4,6-dione (4) and 5-(2,4-dimethoxy benzylidene)-2,2-dimethyl-1,3-dioxane-4,6-dione (5) have been synthesized and their crystal structures have been determined using single crystal X-ray diffractometry for 2, 4 and 5 and X-ray powder diffraction for 3. The nature of intermolecular interactions in 2-5 has been analyzed through Hirshfeld surfaces and 2D fingerprint plots. The DFT optimized molecular geometries in 2-5 agree closely with those obtained from the crystallographic studies. The crystal packing in 2-5 exhibits an interplay of Osbnd H⋯O, Csbnd H⋯O, Csbnd H⋯Cl and Csbnd H⋯π (arene) hydrogen bonds and π⋯π interactions, which assemble molecules into three-dimensional architecture in 2, 3 and 5 and two-dimensional framework in 4. The Hirshfeld surface analyses of 2-5, Meldrum's acid (1) and a few related 5-arylidene derivatives of Meldrum's acid retrieved from the Cambridge Structural Database (CSD) indicate that about 85% of the Hirshfeld surface area (72% in 2 where H⋯Cl contribution is about 13%) in this class of compounds are due to H⋯H, O⋯H and C⋯H contacts. The HOMO-LUMO energy gap (>2.2 eV) in 2-5 indicates a significant degree of internal charge transfer within the molecule.

  16. Synthesis, crystal structure, Hirshfeld surfaces analysis and anti-ischemic activity of cinnamide derivatives

    Science.gov (United States)

    Zhong, Jian-gang; Han, Jia-pei; Li, Xiao-feng; Xu, Yi; Zhong, Yan; Wu, Bin

    2018-02-01

    Two cinnamide derivatives, namely, (E)-1-(4-(bis(4-methylphenyl)- methyl)piperazin-1-yl)-3-(3,4-diethoxyphenyl)prop-2-en-1-one (5) and (E)-1-(4-(bis- (4-fluorophenyl)methyl)piperazin-1-yl)-3-(4-methoxyphenyl)prop-2-en-1-one (6), have been synthesized and characterized by IR spectra, High resolution mass spectra, 1H NMR spectra, 13C NMR spectra. The compound 5 is a novel compound and has never been reported in the literature. Their crystal structures were studied by single-crystal X-ray diffraction. They all crystallize in the monoclinic system. The single-crystal X-ray revealed that compound 5 has infinite X-shaped 1-D polymeric chains structure and compound 6 has a layered 3-D structure by intermolecular interactions. Hirshfeld surface analysis demonstrated the presence of H⋯H, O⋯H, C⋯H, F⋯H, Csbnd H⋯π and π⋯π intermolecular interactions. In addition, the MTT assay results indicated that the compounds 5 and 6 display effective activities against neurotoxicity which is induced by glutamine in PC12 cells. The in vivo experiment indicated that the compound 6 has a good protective effect on cerebral infarction.

  17. Crystal structure and characterization of a novel layered copper-lithium phosphonate with antiferromagnetic intrachain Cu(II)···Cu(II) interactions

    Energy Technology Data Exchange (ETDEWEB)

    Abdelbaky, Mohammed S.M. [Departments of Physical and Analytical Chemistry and Organic and Inorganic Chemistry, University of Oviedo-CINN, 33006 Oviedo (Spain); Amghouz, Zakariae [Scientific and Technical Services, University of Oviedo-CINN, 33006 Oviedo (Spain); Department of Materials Science and Metallurgical Engineering, University of Oviedo, Campus Universitario, 33203 Gijón (Spain); Blanco, David Martínez [Scientific and Technical Services, University of Oviedo-CINN, 33006 Oviedo (Spain); García-Granda, Santiago; García, José R. [Departments of Physical and Analytical Chemistry and Organic and Inorganic Chemistry, University of Oviedo-CINN, 33006 Oviedo (Spain)

    2017-04-15

    Novel metal phosphonate [CuLi(PPA)] [H{sub 3}PPA=3-phosphonopropionic acid] was synthesized hydrothermally and characterized by single-crystal X-ray diffraction, powder X-ray diffraction, scanning electron microscopy, infrared spectroscopy, and thermogravimetric analysis. It crystallizes in the space group C2/c, with cell parameters a=21.617(2) Å, b=4.9269(2) Å, c=14.342(1) Å, β=132.3(2)°, and Z=8. Its framework is built up from a main trimer, acting as a secondary building unit (SBU), which is formed by vertex-shared between two (LiO{sub 4}) and one (Cu(1)O{sub 4}) polyhedra. These units repeat along b-axis forming infinite inorganic chains, these chains are in turn cross-linked by corner sharing with (Cu(2)O{sub 4}) polyhedra to produce inorganic layers lying in the bc-plane. The neighboring layers are connected through the PPA ligand, leading to a 3D pillared-layered structure. The topological analysis reveals that the compound exhibits 3,4,10-c net. Finally, magnetic susceptibility measurement of this compound over the temperature range of 2–300 K reveals the occurrence of weak antiferromagnetic intrachain interactions. - Graphical abstract: Hydrothermal synthesis and structural characterization of a novel lithium-copper phosphonate, formulated as [CuLi(PPA)] (H{sub 3}PPA=3-phosphonopropionic acid), have been reported. This compound has a 3D pillared-layered structure with 3,4,10-c net topology. The magnetic susceptibility data over the temperature range of 2–300 K reveals the occurrence of weak antiferromagnetic interactions. - Highlights: • Novel metal phosphonate, [CuLi(PPA)] (1), has been synthesized and characterized. • Compound 1 has a 3D pillared-layered structure with 3,4,10-c net topology. • Magnetic susceptibility data reveals the occurrence of weak antiferromagnetic interactions.

  18. Green synthesis and characterization of graphene nanosheets

    Energy Technology Data Exchange (ETDEWEB)

    Tavakoli, Farnosh [School of Chemistry, College of Science, University of Tehran, Tehran (Iran, Islamic Republic of); Salavati-Niasari, Masoud, E-mail: salavati@kashanu.ac.ir [Institute of Nano Science and Nano Technology, University of Kashan, Kashan, P. O. Box. 87317-51167, Islamic Republic of Iran (Iran, Islamic Republic of); Department of Inorganic Chemistry, Faculty of Chemistry, University of Kashan, Kashan, P. O. Box. 87317-51167, Islamic Republic of Iran (Iran, Islamic Republic of); Badiei, Alireza [School of Chemistry, College of Science, University of Tehran, Tehran (Iran, Islamic Republic of); Mohandes, Fatemeh [Department of Inorganic Chemistry, Faculty of Chemistry, University of Kashan, Kashan, P. O. Box. 87317-51167, Islamic Republic of Iran (Iran, Islamic Republic of)

    2015-03-15

    Highlights: • For the first time, we have synthesized graphene nanosheets in the presence of pomegranate juice. • Here pomegranate juice was used not only as reductant but also as capping agent. • FT-IR, XRD, SEM, EDS and TEM were used to characterize the samples. • According to TEM image, graphene nanosheet is individually exfoliated after stirring for 24 h. • As shown in the TEM image, graphene monolayer is obtained. - Abstract: For the first time, we have successfully synthesized graphene nanosheets in the presence of pomegranate juice. In this approach, pomegranate juice was used not only as reductant but also as capping agent to form graphene nanosheets. At first, the improved Hummer method to oxidize graphite for the synthesis of graphene oxide (GO) was applied, and then the as-produced graphene oxide was reduced by pomegranate juice to form graphene nanosheets. Fourier transformed infrared (FT-IR), X-ray powder diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectrometry (EDS), high resolution transmission electron microscopy (HRTEM), atomic force microscopy (AFM) and raman were used to characterize the samples. The results obtained from the characterization techniques proved high purity of the final products.

  19. Green synthesis and characterization of graphene nanosheets

    International Nuclear Information System (INIS)

    Tavakoli, Farnosh; Salavati-Niasari, Masoud; Badiei, Alireza; Mohandes, Fatemeh

    2015-01-01

    Highlights: • For the first time, we have synthesized graphene nanosheets in the presence of pomegranate juice. • Here pomegranate juice was used not only as reductant but also as capping agent. • FT-IR, XRD, SEM, EDS and TEM were used to characterize the samples. • According to TEM image, graphene nanosheet is individually exfoliated after stirring for 24 h. • As shown in the TEM image, graphene monolayer is obtained. - Abstract: For the first time, we have successfully synthesized graphene nanosheets in the presence of pomegranate juice. In this approach, pomegranate juice was used not only as reductant but also as capping agent to form graphene nanosheets. At first, the improved Hummer method to oxidize graphite for the synthesis of graphene oxide (GO) was applied, and then the as-produced graphene oxide was reduced by pomegranate juice to form graphene nanosheets. Fourier transformed infrared (FT-IR), X-ray powder diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectrometry (EDS), high resolution transmission electron microscopy (HRTEM), atomic force microscopy (AFM) and raman were used to characterize the samples. The results obtained from the characterization techniques proved high purity of the final products

  20. Analysis and synthesis of one-dimensional magneto-photonic crystals using coupled mode theory

    Energy Technology Data Exchange (ETDEWEB)

    Saghirzadeh Darki, Behnam, E-mail: b.saghirzadeh@ec.iut.ac.ir; Nezhad, Abolghasem Zeidaabadi; Firouzeh, Zaker Hossein

    2017-03-15

    We utilize our previously developed temporal coupled mode approach to investigate the performance of one-dimensional magneto-photonic crystals (MPCs). We analytically demonstrate that a double-defect MPC provides adequate degrees of freedom to design a structure for arbitrary transmittance and Faraday rotation. By using our developed analytic approach along with the numerical transfer matrix method, we present a procedure for the synthesis of an MPC to generate any desired transmittance and Faraday rotation in possible ranges. However it is seen that only discrete values of transmittance and Faraday rotation are practically obtainable. To remedy this problem along with having short structures, we introduce a class of MPC heterostructures which are combinations of stacks with high and low optical contrast ratios.

  1. Lyotropic liquid crystal based on zinc oxide nanoparticles obtained by microwave solvothermal synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Omelchenko, M.M., E-mail: momelchenko@chem.uw.edu.pl [Department of Chemistry, Warsaw University, Al. Zwirki i Wigury 101, 02-089, Warsaw (Poland); Wojnarowicz, J. [Institute of High Pressure Physics, Polish Academy of Sciences, Sokolowska 29/37, Warsaw, 01-142 (Poland); Salamonczyk, M. [Department of Chemistry, Warsaw University, Al. Zwirki i Wigury 101, 02-089, Warsaw (Poland); Lojkowski, W. [Institute of High Pressure Physics, Polish Academy of Sciences, Sokolowska 29/37, Warsaw, 01-142 (Poland)

    2017-05-01

    Abstract: The ZnO nanoparticles, obtained by microwave solvothermal synthesis, were used for the liquid crystal phase preparation. The structure of the material was investigated by X-ray diffraction (XRD), helium pycnometry, specific surface area (SSA), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM). The stability of aqueous suspensions was monitored by Multiple Light Scattering (MLS) technique and the average agglomerate size in suspensions was obtained by dynamic light scattering (DLS) technique. The lyotropic columnar hexagonal phase was formed by doping ZnO nanoparticles into the cetylpiridinium chloride/water/hexanol system. The structure of this phase was confirmed by x-ray diffraction. The luminescent properties of the LC phase were compared with properties of ZnO nanoparticles isolated in solution and analogues lyotropic system without nanoparticles.

  2. Synthesis, Crystal Structure and Water Vapor Adsorption Properties of a Porous Supramolecular Architecture

    Directory of Open Access Journals (Sweden)

    Rui Qiao

    2017-10-01

    Full Text Available A new complex, [Cu4(HL4(H2O14] (1, H3L·HCl = 5-((4-carboxypiperidin-1-ylmethylisophthalic acid hydrochloride, has been prepared and characterized by single-crystal X-ray diffraction, elemental analysis, IR spectroscopy and powder X-ray diffraction (PXRD. The result of the X-ray diffraction analysis reveals that the complex crystallizes in monoclinic, space group C2/c and three unique Cu(II atoms that are connected by partially deprotonated HL2− anion to form a cyclic structure. The rich hydrogen bonding and π-π non-covalent packing interactions extend cyclic units into a three-dimensional (3D supramolecular polymer. Moreover, the thermogravimetric (TG analysis and water vapor adsorption property of 1 were also discussed.

  3. Rare-Earth Calcium Oxyborate Piezoelectric Crystals ReCa4O(BO33: Growth and Piezoelectric Characterizations

    Directory of Open Access Journals (Sweden)

    Fapeng Yu

    2014-07-01

    Full Text Available Rare-earth calcium oxyborate crystals, ReCa4O(BO33 (ReCOB, Re = Er, Y, Gd, Sm, Nd, Pr, and La , are potential piezoelectric materials for ultrahigh temperature sensor applications, due to their high electrical resistivity at elevated temperature, high piezoelectric sensitivity and temperature stability. In this paper, different techniques for ReCOB single-crystal growth are introduced, including the Bridgman and Czochralski pulling methods. Crystal orientations and the relationships between the crystallographic and physical axes of the monoclinic ReCOB crystals are discussed. The procedures for dielectric, elastic, electromechanical and piezoelectric property characterization, taking advantage of the impedance method, are presented. In addition, the maximum piezoelectric coefficients for different piezoelectric vibration modes are explored, and the optimized crystal cuts free of piezoelectric cross-talk are obtained by rotation calculations.

  4. Synthesis and Characterization of Sn2+- based and Bi3+- based metal oxides for photocatalytic applications

    KAUST Repository

    Noureldine, Dalal

    2016-07-01

    The main challenge of water splitting technology is to develop stable, visible responsive photocatalysts that satisfy the thermodynamic requirements to achieve water redox reactions. This study investigates development of the semiconductors containing metals with s2d10 electronic configuration such as Sn2+ or Bi3+ which shifts the valence band position negatively. Efficient water splitting can, however, be only achieved by understanding the fundamental semiconductor properties of underlying processes. This work elucidates the semiconductor properties through two approaches: the first is to synthesize the materials of various stoichiometry in various forms (powders, thin film etc.) and the second is to perform a combined experimental-theoretical studies to determine the optoelectronic properties of the synthesized materials. The study includes the synthesis and characterization of a series of Bi3+ based semiconductors (Bi2Ti2O7, Bi12TiO20, and Bi4Ti3O12) to resolve inconsistencies in their optoelectronic properties. The crystal parameters and stoichiometry were confirmed by the Rietveld refinement and XRD measurements. These compounds showed a UV responsive absorption, high dielectric constants, and low electron and hole effective masses in one crystallographic reflecting their good charge separation and carrier diffusion properties. The approach showed to be accurate in determining the optoelectronic properties due to good agreement between experimental and theoretical values. The second study investigated the synthesis of SnNb2O6 and using flux assisted method which afforded control over the surface. Increasing the flux to reactant molar ratio resulted in a 2D platelets with anisotropic growth along bc plane as confirmed by XRD and SEM. The photocatalytic activity increased while increasing the flux to reactant ratio exceeding solid state synthesis. This method minimized the oxidation of the surface and formation of grain boundaries and enabled the synthesis of

  5. Analysis of Study Trend of Growth and Characterization of CdZnTe Single Crystal

    International Nuclear Information System (INIS)

    Lee, Kyu Hong; Ha, Jang Ho; Kim, Han Soo

    2011-05-01

    CdZnTe (CZT) alloys are very important semiconducting compounds due to their use in several strategic applications in medical, space, and security devices, especially, radiation detector. Specific problems of the bulk crystal growth are still to be solved. However, since industries require excellent bulk CZT crystals, a strong effort is being organized worldwide to optimize the growth process and obtain better material. This report presents the study trend of the bulk CZT crystal growth and characteristics. After the first section where the problems connected to the complicated phase diagram of CZT are presented, the second section describes the various general physical and chemical properties, together with the compensation problems of the CZT material. In the third section, various growth methods are described, paying attention to the defects generated in the different cases. Further, the annealing process which is an essential step for improving the crystal quality is described. In the last section, the general material characterization methods are presented, as a scientific approach for assessing the quality of the bulk crystal

  6. Nanoparticles of the superconductor MgB2: structural characterization and in situ study of synthesis kinetics

    International Nuclear Information System (INIS)

    Cui Chunxiang; Liu Debao; Shen Yutian; Sun Jinbin; Meng Fanbin; Wang Ru; Liu Shuangjin; Greer, A.L.; Chen, S.K.; Glowacki, B.A.

    2004-01-01

    Single-crystal MgB 2 nanoparticles, with diameters in the range 20-100 nm, have been synthesized in situ in the sample chamber of an X-ray diffractometer. The reaction kinetics are analyzed and related to the atomic-level structure of the particles as observed by high-resolution electron microscopy. Synthesis conditions may have a significant influence on microstructure and superconducting properties

  7. Defect characterization of Ga4Se3S layered single crystals by ...

    Indian Academy of Sciences (India)

    Trapping centres in undoped Ga 4 Se 3 S single crystals grown by Bridgman method were characterized for the first time by thermoluminescence (TL) measurements carried out in the low temperature range of 15−300 K. After illuminating the sample with blue light (∼470 nm) at 15 K, TL glow curve exhibited one peak ...

  8. Synthesis, characterization, crystal structure and HSA binding of two new N,O,O-donor Schiff-base ligands derived from dihydroxybenzaldehyde and tert-butylamine

    Science.gov (United States)

    Khosravi, Iman; Hosseini, Farnaz; Khorshidifard, Mahsa; Sahihi, Mehdi; Rudbari, Hadi Amiri

    2016-09-01

    Two new o-hydroxy Schiff-bases compounds, L1 and L2, were derived from the 1:1 M condensation of 2,3-dihydroxybenzaldehyde and 2,4-dihydroxybenzaldehyde with tert-butylamine and were characterized by elemental analysis, FT-IR, 1H and 13C NMR spectroscopies. The crystal structure of L2 was also determined by single crystal X-ray analysis. The crystal structure of L2 showed that the compound exists as a zwitterionic form in the solid state, with the H atom of the phenol group being transferred to the imine N atom. It adopts an E configuration about the central Cdbnd N double bond. Furthermore, binding of these Schiff base ligands to Human Serum Albumin (HSA) was investigated by fluorescence quenching, absorption spectroscopy, molecular docking and molecular dynamics (MD) simulation methods. The fluorescence emission of HSA was quenched by ligands. Also, suitable models were used to analyze the UV-vis absorption spectroscopy data for titration of HSA solution by various amounts of Schiff bases. The spectroscopic studies revealed that these Schiff bases formed 1:1 complex with HSA. Energy transfer mechanism of quenching was discussed and the values of 3.35 and 1.57 nm as the mean distances between the bound ligands and the HSA were calculated for L1 and L2, respectively. Molecular docking results indicated that the main active binding site for these Schiff bases ligands is in subdomain IB. Moreover, MD simulation results suggested that this Schiff base complex can interact with HSA, with a slight modification of its tertiary structure.

  9. Synthesis and Doping of Silicon Nanocrystals for Versatile Nanocrystal Inks

    Science.gov (United States)

    Kramer, Nicolaas Johannes

    The impact of nanotechnology on our society is getting larger every year. Electronics are becoming smaller and more powerful, the "Internet of Things" is all around us, and data generation is increasing exponentially. None of this would have been possible without the developments in nanotechnology. Crystalline semiconductor nanoparticles (nanocrystals) are one of the latest developments in the field of nanotechnology. This thesis addresses three important challenges for the transition of silicon nanocrystals from the lab bench to the marketplace: A better understanding of the nanocrystal synthesis was obtained, the electronic properties of the nanocrystals were characterized and tuned, and novel silicon nanocrystal inks were formed and applied using simple coating technologies. Plasma synthesis of nanocrystals has numerous advantages over traditional solution-based synthesis methods. While the formation of nanoparticles in low pressure nonthermal plasmas is well known, the heating mechanism leading to their crystallization is poorly understood. A combination of comprehensive plasma characterization with a nanoparticle heating model presented here reveals the underlying plasma physics leading to crystallization. The model predicts that the nanoparticles reach temperatures as high as 900 K in the plasma as a result of heating reactions on the nanoparticle surface. These temperatures are well above the gas temperature and sufficient for complete nanoparticle crystallization. Moving the field of plasma nanoparticle synthesis to atmospheric pressures is important for lowering its cost and making the process attractive for industrial applications. The heating and charging model for silicon nanoparticles was adapted in Chapter 3 to study plasmas maintained over a wide range of pressures (10 -- 105 Pa). The model considers three collisionality regimes and determines the dominant contribution of each regime under various plasma conditions. Strong nanoparticle cooling at

  10. Synthesis, structure, growth and characterization of a novel organic NLO single crystal: Morpholin-4-ium p-aminobenzoate

    Energy Technology Data Exchange (ETDEWEB)

    Shanmugam, G. [Department of Physics, Anna University of Technology Tiruchirappalli, Tiruchirappalli 620024 (India); Ravi Kumar, K.; Sridhar, B. [X-ray Crystallography Division, Indian Institute of Chemical Technology, CSIR, Hyderabad 500007 (India); Brahadeeswaran, S., E-mail: sbrag67@yahoo.com [Department of Physics, Anna University of Technology Tiruchirappalli, Tiruchirappalli 620024 (India)

    2012-09-15

    Highlights: ► A new organic NLO crystal morpholin-4-ium p-aminobenzoate has been grown for the first time. ► The structure is reported for the first time in the literature. ► Thermal, optical and SHG studies suggest its suitability for various NLO applications. -- Abstract: The title compound, morpholin-4-ium p-aminobenzoate (MPABA)(C{sub 4}H{sub 10}NO{sup +},C{sub 7}H{sub 6}NO{sub 2}{sup −}), has been synthesized for the first time by the addition of morpholine with 4-aminobenzoic acid in equi-molar ratio and good quality single crystals have been grown by solution growth technique using methanol as a solvent. The molecular structure of the compound was solved and refined by Direct Methods using SHELXS97 and full-matrix least-squares technique using SHELXL97, respectively. MPABA crystallizes in a monoclinic system with unit cell parameters, a = 5.948(5) Å, b = 18.033(4) Å, c = 10.577(5) Å, β = 90.40(1)° and non-centrosymmetric space group Cc. The experimentally measured density and chemical compositions were found to be in good agreement with the theoretical values. The phases and functional groups of MPABA have been identified and confirmed through powder X-ray diffraction and Fourier transform infrared (FTIR) studies, respectively. The thermal stability and decomposition details were studied through TG/DTA thermograms. The UV–visible transmission spectra were recorded for the grown crystal and its NLO characteristic was explored by powder second harmonic generation (SHG) studies.

  11. Sol-gel synthesis of Bi{sub 3.25}La{sub 0.75}Ti{sub 3}O{sub 12} nanotubes

    Energy Technology Data Exchange (ETDEWEB)

    Wang Wen, E-mail: wangwen@hit.edu.cn [Institute for Advanced Ceramics, School of Materials Science and Engineering, Harbin Institute of Technology, No. 92 West Da-Zhi Street, Harbin 150001, Heilongjiang (China); Hua, Ke; Jiancun, Rao; Jinbiao, Feng; Ming, Feng; Dechang, Jia; Yu, Zhou [Institute for Advanced Ceramics, School of Materials Science and Engineering, Harbin Institute of Technology, No. 92 West Da-Zhi Street, Harbin 150001, Heilongjiang (China)

    2011-04-07

    Research highlights: > One-dimensional (1D) ferroelectrics have been successfully synthesized. The sol-gel template synthesis is a versatile and inexpensive technique for producing nanostructures, and particularly facilitates the fabrication of complex oxide nanotubes or nanowires. Compared with the synthesis of the general nanotubes such as carbon nanotubes with simple crystal structure, the synthesis of ferroelectric compound is difficult due to the multielement and the complex crystal structures of these ferroelectrics. Herein, we report the synthesis of one-dimensional BLT nanotubes on anodic alumina (AAO) templates by immersing a template membrane in sol without polymeric additive. - Abstract: Ferroelectric Bi{sub 3.25}La{sub 0.75}Ti{sub 3}O{sub 12} (BLT) nanotubes were synthesized by sol-gel technique using nanochannel porous anodic aluminum oxide (AAO) templates, and were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM) and high resolution transmission electron microscopy (HRTEM). BLT nanotubes with diameter of around 240 nm and the wall thickness of about 25 nm exhibited a single orthorhombic perovskite structure and highly preferential crystal growth along the [1 1 7] orientation, which have smooth wall morphologies and well-defined diameters corresponding to the diameter of the applied template. The formation mechanism of BLT nanotubes was discussed.

  12. Synthesis, X-ray crystal structure and theoretical calculations of antileishmanial neolignan analogues

    Energy Technology Data Exchange (ETDEWEB)

    Nascimento, Josenaide P. do; Santos, Lourivaldo S.; Carmo, Maria Carolina L. do; Brasil, Davi S.B.; Alves, Claudio N., E-mail: nahum@ufpa.b [Universidade Federal do Para (UFPA), Belem, PA (Brazil). Inst. de Ciencias Exatas e Naturais; Santos, Regina Helena A.; Tozzo, Erica; Ferreira, Janaina G. [Universidade de Sao Paulo (IQSC/USP), Sao Carlos, SP (Brazil). Inst. de Quimica

    2010-07-01

    The synthesis and X-ray crystal diffraction structure of two analogues of neolignans, 2-(4-chlorophenyl)-1-phenylethanone (20) and 2-[(4-chlorophenyl)thio]-1-(3,4-dimethoxyphenyl) propan-1-one (12) is described. The compound 12 presents activity against intracellular Leishmania donovani and Leishmania amazonensis amastigotes that cause cutaneous and visceral leishmaniasis. In addition, the density functional theory (DFT) with the B3LYP hybrid functional was employed to calculate a set of molecular descriptors for nineteen synthetic analogues of neolignans with antileishmanial activities. Afterwards, the stepwise discriminant analysis was performed to investigate possible relationship between the molecular descriptors and biological activities. Through this analysis the compounds were classified into two groups active and inactive according to their degree of biological activities, and the more important properties were charges on some key atoms, electronic affinity and ClogP. (author)

  13. Synthesis, X-ray crystal structure and theoretical calculations of antileishmanial neolignan analogues

    International Nuclear Information System (INIS)

    Nascimento, Josenaide P. do; Santos, Lourivaldo S.; Carmo, Maria Carolina L. do; Brasil, Davi S.B.; Alves, Claudio N.; Santos, Regina Helena A.; Tozzo, Erica; Ferreira, Janaina G.

    2010-01-01

    The synthesis and X-ray crystal diffraction structure of two analogues of neolignans, 2-(4-chlorophenyl)-1-phenylethanone (20) and 2-[(4-chlorophenyl)thio]-1-(3,4-dimethoxyphenyl) propan-1-one (12) is described. The compound 12 presents activity against intracellular Leishmania donovani and Leishmania amazonensis amastigotes that cause cutaneous and visceral leishmaniasis. In addition, the density functional theory (DFT) with the B3LYP hybrid functional was employed to calculate a set of molecular descriptors for nineteen synthetic analogues of neolignans with antileishmanial activities. Afterwards, the stepwise discriminant analysis was performed to investigate possible relationship between the molecular descriptors and biological activities. Through this analysis the compounds were classified into two groups active and inactive according to their degree of biological activities, and the more important properties were charges on some key atoms, electronic affinity and ClogP. (author)

  14. Mimicking the properties of antifreeze glycoproteins: synthesis and characterization of a model system for ice nucleation and antifreeze studies.

    Science.gov (United States)

    Hederos, Markus; Konradsson, Peter; Borgh, Annika; Liedberg, Bo

    2005-08-25

    Synthesis of beta-D-Gal-(1 --> 3)-beta-D-GalNAc coupled to HOC2H4NHCOC15H30SH is described. This compound was coadsorbed at various proportions with C2H5OC2H4NHCOC15H30SH to form statistically mixed self-assembled monolayers (SAMs) on gold in an attempt to mimic the properties of the active domain in antifreeze glycoproteins (AFGPs). The monolayers were characterized by null ellipsometry, contact angle goniometry, X-ray photoelectron spectroscopy, and infrared reflection-absorption spectroscopy. The disaccharide compound adsorbed preferentially, and SAMs prepared at a solution molar ratio >0.3 displayed total wetting. The mixed SAMs showed well-organized alkyl chains up to a disaccharide surface fraction of 0.8. The amount of gauche conformers in the alkyls increased rapidly above this point, and the monolayers became disordered and less densely packed. Furthermore, the generated mixed SAMs were subjected to water vapor at constant relative humidity and the subsequent ice crystallization on a cooled substrate was monitored via an optical microscope. Interestingly, rapid crystallization occurred within a narrow range of temperatures on mixed SAMs with a high disaccharide content, surface fraction >0.3. The reported crystallization temperatures and the ice layer topography were compared with results obtained for a much simpler reference system composed of -OH/-CH3 terminated n-alkanethiols in order to account for changes in topography of the water/ice layer with surface energy. Although preliminary, the obtained results can be useful in the search for the molecular mechanism behind the antifreeze activity of AFGPs.

  15. Bulk crystal growth and electronic characterization of the 3D Dirac semimetal Na3Bi

    Directory of Open Access Journals (Sweden)

    Satya K. Kushwaha

    2015-04-01

    Full Text Available High quality hexagon plate-like Na3Bi crystals with large (001 plane surfaces were grown from a molten Na flux. The freshly cleaved crystals were analyzed by low temperature scanning tunneling microscopy and angle-resolved photoemission spectroscopy, allowing for the characterization of the three-dimensional (3D Dirac semimetal (TDS behavior and the observation of the topological surface states. Landau levels were observed, and the energy-momentum relations exhibited a linear dispersion relationship, characteristic of the 3D TDS nature of Na3Bi. In transport measurements on Na3Bi crystals, the linear magnetoresistance and Shubnikov-de Haas quantum oscillations are observed for the first time.

  16. Synthesis and structural characterization of nano-hydroxyapatite biomaterials prepared by microwave processing

    Science.gov (United States)

    Ramli, Rosmamuhamadani; Arawi, Ainaa Zafirah Omar; Talari, Mahesh Kumar; Mahat, Mohd Muzamir; Jais, Umi Sarah

    2012-07-01

    Synthetic hydroxyapatite, (HA, Ca10(PO4)6(OH)2), is an attractive and widely utilized bio-ceramic material for orthopedic and dental implants because of its close resemblance of native tooth and bone crystal structure. Synthetic HA exhibits excellent osteoconductive properties. Osteoconductivity means the ability to provide the appropriate scaffold or template for bone formation. Calcium phosphate biomaterials [(HA), tri-calcium phosphate (TCP) and biphasic calcium phosphate (HA/TCP)] with appropriate three-dimensional geometry are able to bind and concentrate endogenous bone morphogenetic proteins in circulation, and may become osteoinductive and can be effective carriers of bone cell seeds. This HA can be used in bio-implants as well as drug delivery application due to the unique properties of HA. Biomaterials synthesized from the natural species like mussel shells have additional benefits such as high purity, less expensive and high bio compatibility. In this project, HA-nanoparticles of different crystallite size were prepared by microwave synthesis of precursors. High purity CaO was extracted from the natural mussel shells for the synthesis of nano HA. Dried nano HA powders were analyzed using X-Ray Diffraction (XRD) technique for the determination of crystal structure and impurity content. Scanning Electron Microscopic (SEM) investigation was employed for the morphological investigation of nano HA powders. From the results obtained, it was concluded that by altering the irradiation time, nano HA powders of different crystallite sizes and morphologies could be produced. Crystallite sizes calculated from the XRD patterns are found to be in the range of 10-55 nm depending on the irradiation time.

  17. Controllable Growth of Monolayer MoS2 and MoSe2 Crystals Using Three-temperature-zone Furnace

    Science.gov (United States)

    Zheng, Binjie; Chen, Yuanfu

    2017-12-01

    Monolayer molybdenum disulfide (MoS2) and molybdenum diselenide (MoSe2) have attracted a great attention for their exceptional electronic and optoelectronic properties among the two dimensional family. However, controllable synthesis of monolayer crystals with high quality needs to be improved urgently. Here we demonstrate a chemical vapor deposition (CVD) growth of monolayer MoS2 and MoSe2 crystals using three-temperature-zone furnace. Systematical study of the effects of growth pressure, temperature and time on the thickness, morphology and grain size of crystals shows the good controllability. The photoluminescence (PL) characterizations indicate that the as-grown monolayer MoS2 and MoSe2 crystals possess excellent optical qualities with very small full-width-half-maximum (FWHM) of 96 me V and 57 me V, respectively. It is comparable to that of exfoliated monolayers and reveals their high crystal quality. It is promising that our strategy should be applicable for the growth of other transition metal dichalcogenides (TMDs) monolayer crystals.

  18. TCNQ-embedded heptacene and nonacene: Synthesis, characterization and physical properties

    KAUST Repository

    Ye, Qun

    2013-01-01

    Incorporation of 7,7,8,8-tetracyanoquinodimethane (TCNQ) moieties into the acene backbone has been successfully achieved and two heptacene-TCNQ derivatives and one nonacene-TCNQ derivative have been synthesized and well characterized. Two TCNQ moieties have been embedded into heptacene and nonacene backbones for the first time. All the three compounds have good stability and solubility due to the presence of TCNQ moieties. Single crystal analysis revealed a bent butterfly-like conformation of these molecules. Their charge transport properties have been characterized using organic field effect transistors (OFETs). © 2013 The Royal Society of Chemistry.

  19. Synthesis and characterization of the cyanobenzene-ethylenedithio-TTF donor

    Directory of Open Access Journals (Sweden)

    Sandrina Oliveira

    2015-06-01

    Full Text Available A dissymmetric TTF-type electron donor, cyanobenzene-ethylenedithio-tetrathiafulvalene (CNB-EDT-TTF, was obtained in high yield, by a cross-coupling reaction with triethyl phosphite between 2-thioxobenzo[d][1,3]dithiole-5-carbonitrile and 5,6-dihydro-[1,3]dithiolo[4,5-b][1,4]dithiin-2-one. This new donor was characterized namely by single crystal X-ray diffraction, cyclic voltammetry, NMR, UV-visible and IR spectroscopy.

  20. Characterization of monoclinic crystals in tablets by pattern-fitting procedure using X-ray powder diffraction data.

    Science.gov (United States)

    Yamamura, Shigeo; Momose, Yasunori

    2003-06-18

    The purpose of this study is to characterize the monoclinic crystals in tablets by using X-ray powder diffraction data and to evaluate the deformation feature of crystals during compression. The monoclinic crystals of acetaminophen and benzoic acid were used as the samples. The observed X-ray diffraction intensities were fitted to the analytic expression, and the fitting parameters, such as the lattice parameters, the peak-width parameters, the preferred orientation parameter and peak asymmetric parameter were optimized by a non-linear least-squares procedure. The Gauss and March distribution functions were used to correct the preferred orientation of crystallites in the tablet. The March function performed better in correcting the modification of diffraction intensity by preferred orientation of crystallites, suggesting that the crystallites in the tablets had fiber texture with axial orientation. Although a broadening of diffraction peaks was observed in acetaminophen tablets with an increase of compression pressure, little broadening was observed in the benzoic tablets. These results suggest that "acetaminophen is a material consolidating by fragmentation of crystalline particles and benzoic acid is a material consolidating by plastic deformation then occurred rearrangement of molecules during compression". A pattern-fitting procedure is the superior method for characterizing the crystalline drugs of monoclinic crystals in the tablets, as well as orthorhombic isoniazid and mannitol crystals reported in the previous paper.

  1. Synthesis, characterization and thermal decomposition of tetramethylammonium rare earth double selenates

    Science.gov (United States)

    Divekar, Sandesh K.; Achary, S. Nagabhusan; Ajgaonkar, Vishnu R.

    2018-06-01

    A series of double selenates, as (CH3)4NLn(SeO4)2rad 4H2O (Ln = Rare earth ion like La, Pr, Nd, Sm, Gd, Tb, Dy) was crystallized from mixed solution and characterized in detail for their structure, vibrational and optical properties as well as thermal stabilities. The crystal structure of the praseodymium compound was obtained by single crystal X-ray diffraction (XRD) and revealed a monoclinic (C2/c) lattice with chains formed by PrO8 and SeO4 units. The chains with compositions [Pr(SeO4)4(H2O)4]- are stacked in three dimensions and the (CH3)4N+ ions located in between them provide charge neutrality to the structure. The characterization of other compounds were carried out from powder XRD data and revealed that they all are isostructural to Pr-compound. All the functional groups were identified by Raman and IR spectroscopic studies. Solid state 77Se NMR revealed noticeable changes in selenium environment in these compounds. The optical absorption studies on the compounds show strong band edge absorptions in UV region. Thermal stabilities of the compounds, as investigated by simultaneous TG-DTA techniques indicate their sequential decompositions due to loss of H2O, (CH3)4N+ group, SeO2 and finally leaving their corresponding rare earth oxides.

  2. Polyol synthesis of silver nanoplates: The crystal growth mechanism based on a rivalrous adsorption

    International Nuclear Information System (INIS)

    Luo Xiaolin; Li Zongxiao; Yuan Chunlan; Chen Yashao

    2011-01-01

    Highlights: → Silver nanoplates have been successfully synthesized by polyol reduction in the presence of poly (vinylpyrrolidone) (PVP) and HNO 3 . → Due to the discovery of CN - ions in the solution, a mechanism for the anisotropic growth of silver nanoplates is systematically discussed. → TG, FT-IR and SERS were used to provide some direct evidences of rivalrous adsorption between PVP and CN - ions on the surface of the silver crystals. - Abstract: A polyol reducing approach has been applied to synthesize silver nanoplates with an average thickness of 50 nm and edge length of 3 μm in the presence of poly (vinylpyrrolidone) (PVP) and HNO 3 . X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscropy (TEM), and electron diffraction are used to characterize these silver nanoplates. Findings indicate that the nanoplates are single crystals and with their basal plane as (1 1 1) lattice plane. On the basis of the results from thermogravimetric analysis (TG), Fourier transform infrared spectroscopy (FT-IR) and Raman spectroscopy, a crystal growth mechanism based on the rivalrous adsorption between PVP and CN - ions on the surface of silver nanoplates is supposed to explain the crystal anisotropic growth.

  3. Synthesis and crystal structure of rare earth complexes with o-nitrobenzoic acid and N, N-dimethylformamide

    Science.gov (United States)

    Zhao, Lifang; Chen, Yashao; Bao, Lin

    2010-03-01

    The rare-earth compound [Ce 0.5Sm 0.5( o-NBA) 3(DMF) 2] 2 (where o-NBA = o-nitrobenzoic acid, DMF = N, N-dimethylformamide) has been synthesized and structurally characterized. The crystal structure of the compound is characterized by Fourier transfer infrared spectroscopy (FT-IR), fluorescent emission spectroscopy (FES) and single-crystal X-ray diffraction. The results show that the compound crystallizes in a triclinic system, space group P-1 with a = 11.8284 (6) Å, b = 12.5082 (7) Å, c = 13.0203 (7) Å, α = 63.9650 (10)°, β = 66.3900 (10)°, γ = 71.7380 (10)°, V = 1563.7 (14) Å 3, Dc = 1.677 g/cm 3, Z = 1, F(0 0 0) = 790. Each Ln (III) atom is bridged by four o-nitro-benzoates and chelated by one o-nitrobenzoate. The Ln (III) atom is eight-coordinated by six oxygen atoms from five o-nitro-benzoates and two oxygen atoms from two DMF molecules. Hydrogen bonds and aromatic π⋯ π stacking interactions assemble the compound into a three-dimensional network. Luminescence measurement shows that the compound emits fluorescence.

  4. Synthesis and characterization of magnetic opal/Fe3O4 colloidal crystal

    Science.gov (United States)

    Carmona-Carmona, A. J.; Palomino-Ovando, M. A.; Hernández-Cristobal, Orlando; Sánchez-Mora, E.; Toledo-Solano, M.

    2017-03-01

    We report an experimental study of colloidal crystals based on SiO2 artificial opals, infiltrated with 1.34(M1), 2.03(M2) and 24.4(M3) wt% Fe3O4 nanoparticles, using the co-assembly method. Scanning electron microscopy (SEM), X-ray diffraction (XRD), Raman spectroscopy and Vibration sample magnetometer (VSM) were used to study the structural, magnetic and optical properties of the samples. At 300 K all the samples exhibit superparamagnetic behavior due to the magnetic coupling of Fe3O4 nanoparticles infiltrated into opal. However, for higher concentration of nanoparticles this strong coupling distorts the opal network. The UV-vis diffuse reflectance spectroscopy and Kubelka-Munk theory were applied to determine that the energy band gap of the opal-magnetite composites can be adjusted by varying the concentration of Fe3O4 nanoparticles. This values are between the energy band gap of SiO2 and Fe3O4.

  5. Synthesis and Crystal Structures of Two Metal Complexes Incorporating Malonate and Organodiamine Ligands

    International Nuclear Information System (INIS)

    Zhang, Quan Zheng; Yang, Wen Bin; Chen, Shu Mei; Lu, Can Zhong

    2005-01-01

    In the present work we report the synthesis and X-ray crystal structures of two new malonato complexes incorporating organodiamine ligands: [Ni(phen)(mal)(H_2O)_2]·3H_2O (H_2mal = malonic acid, phen = 1,10-phenanthroline) and [Zn(bpy)(H_2O)]_2[Zn(bpy)(mal)(H_2O)_2]_2(NO_3)_4·4H_2O (bpy = 2,2'-bipyridine). Investigation on novel organic-inorganic hybrid framework assemblies represents one of the most active areas of material science and chemical research. Major advances have been made in these materials due to their interesting properties and potential in various applications, e. g., electrical conductivity, magnetism, host-guest chemistry, ion exchange, catalysis, nonlinear optics, etc. Moreover, discovery and design of such new materials with specific networks remain of a particularly important and active subject in the field of supramolecuar chemistry and crystal engineering. A variety of complexes with interesting compositions and topologies have been prepared through taking certain factors into account, such as the coordination nature of the metal ion and the shape, functionality, flexibility, and symmetry of organic ligand. Recently, some dicarboxylate ligands, such as oxalate, malonate, and terephthalate, have been widely used in the construction of these interesting structures

  6. Synthesis and Characterization of Ferroelectric Liquid Crystalline Organosiloxanes Containing 4-(4-undecanyloxy bi-phenyl-1-carboxyloxyphenyl (2S,3S-2-chloro-3-methylvalerate and 4-(4-undecanyloxybenzoyloxybiphenyl (2S,3S-2-chloro-3-methylvalerate

    Directory of Open Access Journals (Sweden)

    Chih-Hung Lin

    2013-10-01

    Full Text Available A series of new organosiloxane ferroelectric liquid crystalline (FLC materials have been synthesized, and their mesomorphic and physical properties have been characterized. Four new disiloxanes and trisiloxanes, containing biphenyl 4-hydroxybenzoate and phenyl 4-hydroxybiphenylcarboxylate as mesogenic units and eleven methylene unit as spacers and (2S,3S-2-chloro-3-methylvalerate unit as chiral end groups. The molecule, using three phenyl ring as a mesogenic unit, formulates much wider liquid crystalline phase temperature ranges than that of a two phenyl ring unit. The phenyl arrangement differences of mesogenic unit result in the greater differences of the liquid crystal phase formation. The siloxane molecule induction is helpful to the more regular smectic phase formation and smectic phase stabilization, such as chiral SC (SC* and SB phases. The siloxane molecule is helpful to reduce the phase transition temperature and broaden the liquid crystal temperature range of the SC* phase and, simultaneously, it will not induce chain crystallization phenomenon and dilute the Ps value. The synthesis and characterization of the new FLCs materials, which exhibit a room temperature SC* phase and higher spontaneous polarization are presented.

  7. Cross-linked lysozyme crystal templated synthesis of Au nanoparticles as high-performance recyclable catalysts

    International Nuclear Information System (INIS)

    Liang Miao; Liu Xia; Qi Wei; Su Rongxin; Huang Renliang; Yu Yanjun; He Zhimin; Wang Libing

    2013-01-01

    Bio-nanomaterials fabricated using a bioinspired templating technique represent a novel class of composite materials with diverse applications in biomedical, electronic devices, drug delivery, and catalysis. In this study, Au nanoparticles (NPs) are synthesized within the solvent channels of cross-linked lysozyme crystals (CLLCs) in situ without the introduction of extra chemical reagents or physical treatments. The as-prepared AuNPs-in-protein crystal hybrid materials are characterized by light microscopy, transmission electron microscopy, x-ray diffraction, and Fourier-transform infrared spectroscopy analyses. Small AuNPs with narrow size distribution reveal the restriction effects of the porous structure in the lysozyme crystals. These composite materials are proven to be active heterogeneous catalysts for the reduction of 4-nitrophenol to 4-aminophenol. These catalysts can be easily recovered and reused at least 20 times because of the physical stability and macro-dimension of CLLCs. This work is the first to use CLLCs as a solid biotemplate for the preparation of recyclable high-performance catalysts. (paper)

  8. Confinement stabilises single crystal vaterite rods.

    OpenAIRE

    Schenk, AS; Albarracin, EJ; Kim, YY; Ihli, J; Meldrum, FC

    2014-01-01

    Single-crystals of vaterite, the least-stable anhydrous polymorph of CaCO3, are rare in biogenic and synthetic systems. We here describe the synthesis of high aspect ratio single crystal vaterite rods under additive-free conditions by precipitating CaCO3 within the cylindrical pores of track-etch membranes.

  9. Synthesis, characterization and visible light photocatalytic activity of Cr 3+ , Ce 3+ and N co-doped TiO 2 for the degradation of humic acid

    KAUST Repository

    Rashid, S. G.; Gondal, M. A.; Hameed, A.; Aslam, M.; Dastageer, M. A.; Yamani, Z. H.; Anjum, Dalaver H.

    2015-01-01

    The synthesis, characterization and photocatalytic activity of Cr3+ and Ce3+ co-doped TiON (N-doped TiO2) for the degradation of humic acid with exposure to visible light is reported. The synthesized bimetal (Cr3+ + Ce3+) modified TiON (Cr-Ce/TiON), with an evaluated bandgap of 2.1 eV, exhibited an enhanced spectral response in the visible region as compared to pure and Ce3+ doped TiON (Ce/TiON). The XRD analysis revealed the insertion of Cr3+ and Ce3+ in the crystal lattice along with Ti4+ and N that resulted in the formation of a strained TiON anatase structure with an average crystallite size of ∼10 nm. Raman analysis also supported the formation of stressed rigid structures after bimetal doping. HRTEM confirmed the homogeneous distribution of both the doped metallic components in the crystal lattice of TiON without the formation of surface oxides of either Cr3+ or Ce3+. Electron energy loss spectroscopy (EELS) analysis revealed no change in the oxidation of either Cr or Ce during the synthesis. The synthesized Cr-Ce/TiON catalyst exhibited appreciable photocatalytic activity for the degradation of humic acid on exposure to visible light. Additionally, a noticeable mineralization of carbon rich humic acid was also witnessed. The photocatalytic activity of the synthesized catalyst was compared with pristine and Ce3+ doped TiON. © The Royal Society of Chemistry 2015.

  10. Solution-mediated growth of NBA-ZSM-5 crystals retarded by gel entrapment

    Science.gov (United States)

    Aguilar-Mamani, Wilson; Akhtar, Farid; Hedlund, Jonas; Mouzon, Johanne

    2018-04-01

    The synthesis of flat tablet-shaped ZSM-5 crystals from a gel using metakaolin as aluminosilicate source and n-butyl amine as structure directing agent was investigated. The evolution inside the solid phase was characterized by X-ray diffraction, scanning electron microscopy, energy dispersive spectroscopy, thermogravimetry and mass spectrometry. A kinetic study indicated that the nucleation of the majority crystals occurred concurrently with the formation of the gel upon heating the starting liquid suspension. Microstructural evidences undeniably showed that the gel precipitated on ZSM-5 crystals and mineral impurities originating from kaolin. As a result, crystal growth was retarded by gel entrapment, as indicated by the configuration and morphology of the embedded crystals. The results presented herein are harmonized with a solution-mediated nucleation and growth mechanism. Our observations differ from the autocatalytic model that suggests that the nuclei rest inside the gel until released when the gel is consumed. Our results show instead that it is crystals that formed in an early stage before entrapment inside the gel that rest inside the gel until exposed at the gel surface. These results illustrate the limitation of the classical method used in the field to determine nucleation profiles when the crystals become trapped inside the gel.

  11. Crystal growth and characterization of CeFe{sub 1-x}Ru{sub x} PO

    Energy Technology Data Exchange (ETDEWEB)

    Balle, Tanita; Kliemt, Kristin; Krellner, Cornelius [Goethe Universitaet Frankfurt, Kristall- und Materiallabor (Germany)

    2016-07-01

    CeRuPO is a one of the few heavy fermion systems, which order ferromagnetically at low temperatures (T{sub C} = 15 K), because of dominant RKKY-interaction. CeFePO on the other hand shows no long-range magnetic order even at low temperatures because of dominant Kondo effect (T{sub K} = 10 K). By substituting CeFePO with ruthenium we can reach a quantum critical point, at which the RKKY-interaction and the Kondo effect are equally strong. To study the quantum critical point, and to enlighten the question if the order stays ferromagnetically down to lowest temperatures, high quality crystals are needed. Here, the growth and characterization of the single crystals will be discussed. We obtained mm-sized single crystals of the unsubstituted CeRuPO and CeFePO by a modified Bridgeman method using tin as a flux. The quality of the crystals was verified by Powder-X-Ray-Diffraction, energy dispersive X-ray spectroscopy and Laue backscattering.

  12. Boron-based nanostructures: Synthesis, functionalization, and characterization

    Science.gov (United States)

    Bedasso, Eyrusalam Kifyalew

    Boron-based nanostructures have not been explored in detail; however, these structures have the potential to revolutionize many fields including electronics and biomedicine. The research discussed in this dissertation focuses on synthesis, functionalization, and characterization of boron-based zero-dimensional nanostructures (core/shell and nanoparticles) and one-dimensional nanostructures (nanorods). The first project investigates the synthesis and functionalization of boron-based core/shell nanoparticles. Two boron-containing core/shell nanoparticles, namely boron/iron oxide and boron/silica, were synthesized. Initially, boron nanoparticles with a diameter between 10-100 nm were prepared by decomposition of nido-decaborane (B10H14) followed by formation of a core/shell structure. The core/shell structures were prepared using the appropriate precursor, iron source and silica source, for the shell in the presence of boron nanoparticles. The formation of core/shell nanostructures was confirmed using high resolution TEM. Then, the core/shell nanoparticles underwent a surface modification. Boron/iron oxide core/shell nanoparticles were functionalized with oleic acid, citric acid, amine-terminated polyethylene glycol, folic acid, and dopamine, and boron/silica core/shell nanoparticles were modified with 3-(amino propyl) triethoxy silane, 3-(2-aminoethyleamino)propyltrimethoxysilane), citric acid, folic acid, amine-terminated polyethylene glycol, and O-(2-Carboxyethyl)polyethylene glycol. A UV-Vis and ATR-FTIR analysis established the success of surface modification. The cytotoxicity of water-soluble core/shell nanoparticles was studied in triple negative breast cancer cell line MDA-MB-231 and the result showed the compounds are not toxic. The second project highlights optimization of reaction conditions for the synthesis of boron nanorods. This synthesis, done via reduction of boron oxide with molten lithium, was studied to produce boron nanorods without any

  13. Biomimetic and Aggregation-Driven Crystallization Route for Room-Temperature Material Synthesis: Growth of β-Ga2O3 Nanoparticles Using Peptide Assemblies as Nanoreactors

    Science.gov (United States)

    Lee, Sang-Yup; Gao, Xueyun; Matsui, Hiroshi

    2008-01-01

    The room temperature synthesis of β-Ga2O3 nanocrystal was examined by coupling two biomimetic crystallization techniques, the enzymatic peptide nano-assembly templating and the aggregation-driven crystallization. The catalytic template of peptide assembly nucleated and mineralized primary β-Ga2O3 crystals, and then fused them to grow single-crystalline and monodisperse nanoparticles in the cavity of the peptide assembly at room temperature. In this work, the peptide assembly was exploited as a nano-reactor with an enzymatic functionality catalyzing the hydrolysis of gallium precursors. In addition, the characteristic ring-structure of peptide assembly is expected to provide an efficient dehydration pathway and the crystallization control over the surface tension, which are advantageous for the β-Ga2O3 crystal growth. This multifunctional peptide assembly could be applied for syntheses of a variety of nanomaterials that are kinetically difficult to grow at room temperature. PMID:17302413

  14. Synthesis of single-crystal perovskite PbCrO3 through a new reaction route at high pressure

    Science.gov (United States)

    Han, Yunxia; Wang, Shanmin; Liu, Yinjuan; Ma, Dejiang; He, Duanwei; Zhao, Yusheng

    2018-04-01

    As a new member in the family of Mott system, perovskite PbCrO3 has recently been uncovered to exhibit fantastic structural transition under pressure, coupled with magnetic, electronic, and ferromagnetic transitions, which provide many opportunities for understanding of correlated system. However, it is still challenging to synthesize high-quality single-crystal PbCrO3, leading to the limited exploration of this Mott compound. In this work, we formulate a new high-pressure reaction route for preparation of high-quality PbCrO3 crystals between PbCl2 and Na2CrO4 at high pressure of 5-10 GPa and at high temperature of 750-1500°C. Because of the formation of reaction byproduct NaCl, the final product can readily be separated by washing with water. The obtained sample is in the form of single crystal with crystallite size up to 200 μm. In addition, combined with X-ray diffraction measurement, a tentative pressure-temperature synthesis diagram of PbCrO3 is mapped out from the reaction between PbCl2 and Na2CrO4 and the reaction mechanism is also explored in detail.

  15. Microwave-Hydrothermal Synthesis and Characterization of High-Purity Nb Doped BaTiO3 Nanocrystals

    Directory of Open Access Journals (Sweden)

    A. Khanfekr

    2014-01-01

    Full Text Available The synthesis of Nb doped BaTiO3 has been investigated under Microwave-Hydrothermal (MH conditions in the temperature of 150°C for only 2 h using C16H36O4Ti, BaH2O2.8H2O and NbCl5 as Ba, Ti and  Nb sources, respectively.  Typical experiments performed on MH processing have not yet reported for Nb doped BaTiO3.  In the MH process, the formation of high purity nano tetragonal Nb-BaTiO3 was strongly enhanced. New hydrothermal method was used instead of the previous solid state reaction for the BaTiO3±Nb2O3 system. The new method uses high pressure to create nano dimension particles in a lower time and temperature. In case of the phase evolution studies, the XRD pattern measurements and Raman spectroscopy were performed. TEM and FE-SEM images were taken for the detailed analysis of the particle size, surface and morphology.  Synthesis of Nb doped BaTiO3 with the Microwave-hydrothermal provides an advantage of fast crystallization and reduced crystal size when compared to existing methods.

  16. Studies on the growth and characterization of tris (glycine) calcium({Iota}{Iota}) dichloride-a nonlinear optical crystal

    Energy Technology Data Exchange (ETDEWEB)

    Dhanaraj, P.V. [Centre for Crystal Growth, SSN College of Engineering, Kalavakkam 603 110 (India); Rajesh, N.P., E-mail: rajeshnp@ssn.edu.i [Centre for Crystal Growth, SSN College of Engineering, Kalavakkam 603 110 (India)

    2011-01-01

    A systematic characterization of a novel nonlinear optical material tris (glycine) calcium({Iota}{Iota}) dichloride (TGCC) is performed. The solubility and metastable zone width of TGCC were studied. TGCC single crystal of dimensions 34x23x5 mm{sup 3} was grown by the slow evaporation technique. Single crystal X-ray diffraction studies reveal that the crystal belongs to orthorhombic system. Energy dispersive X-ray analysis confirms the presence of elements in the crystal. Structural perfection of the as-grown single crystal was studied through multicrystal X-ray diffraction analysis. The thermal characteristics of TGCC were analyzed by thermogravimetric and differential thermal analysis and differential scanning calorimetry. The transmittance of TGCC crystal has been used to calculate the optical band gap of the crystal. Chemical etching studies of TGCC crystal was carried out. The dielectric and mechanical behavior of the crystals were analyzed. The second harmonic conversion property of TGCC was identified by the Kurtz and Perry powder technique and was observed to be higher than that of KDP.

  17. Synthesis, purification and characterization of [3,5 - T] p-aminobenzoic acid

    International Nuclear Information System (INIS)

    Corol-Cucu, Delia-Irina; Chiper, Diana; Mihaila, V.; Negoita, N.

    2000-01-01

    This paper refers to the synthesis, purification and characterization of [3,5-T] p-aminobenzoic acid (PAB,H' vitamine). The p-aminobenzoic acid is used in the treatment of rheumatic arthritis and dermatological affections. The advantage of tritium labelling of p-aminobenzoic acid is that some biomedical important aspects of collagen's behaviour are made clear. The PAB stimulate the grow of intestinal bacteria so necessary to synthesis of some vitamins (bio tine, pantothenic acid). Tritium is the only radioactive isotope of hydrogen. Several steps have to be carried out in the synthesis of the final product as well as to study its biological behavior. For the labelling of PAB one prefers the substitution of bromine from PAB-3,5-Br with tritium because of simplicity of reaction and the easy synthesis of halogen compound. The first step in synthesis is the protection of NH 2 group through acetylation of PAB. After that PAB is bromated into the 3 and 5 position with elementary bromine. The raw compound is purified and recrystallized and characterized through thin layer chromatography.The tritium labelling is performed through substitution of bromine from bromate derivative, using Pd/C (10% Pd) as catalyst and low basic conditions for the neutralization of HBr resulting from reaction. After the separation of PAB-3,5-T through filtration, the catalyst remains on the filter paper and the labelled compound goes in aqueous solution. PAB-3,5-T is purified through thin layer chromatography with the solvent system n-BuOH:NH 4 OH(25%):H 2 O:EtOH (8:1:2:2,5, v/v) with silica gel GF 254 as support. The determination of activity is carried out with LSC (Liquid Scintillation Counter). A 98% purity was determined through TLC in the same conditions while determination of activity distribution was performed with a 2π Berthold scanner with gas running and without window. The chemical concentration has been measured through UV spectrophotometry and by comparing extinction with

  18. Purification, crystallization and preliminary X-ray characterization of a haemagglutinin from the seeds of Jatropha curcas

    International Nuclear Information System (INIS)

    Nair, Divya N.; Suresh, C. G.; Singh, Desh Deepak

    2011-01-01

    A novel haemagglutinin from Jatropha curcas seeds is purified and crystallized. X-ray diffraction data collected from the rod-shaped crystals were processed in the orthorhombic space group P2 1 2 1 2 1 and the crystals diffracted to 2.8 Å resolution at 103 K. The plant Jatropha curcas (Euphorbiaceae) is an important source of biofuel from the inedible oil present in its toxic seeds. The toxicity arises from the presence of curcin, a ribosome-inactivating protein showing haemagglutination activity. In this communication, the purification, crystallization and preliminary X-ray characterization are reported of a small protein isolated from J. curcas seeds with a molecular mass of ∼10 kDa that agglutinates rabbit erythrocytes. The protein was crystallized using the hanging-drop vapour-diffusion method and also by the microbatch method in 72-well HLA plates, using PEG 8000 as the precipitant in both conditions. X-ray diffraction data collected from the rod-shaped crystals were processed in the orthorhombic space group P2 1 2 1 2 1 . The crystals diffracted to 2.8 Å resolution at 103 K

  19. Growth and characterization of calcium hydrogen phosphate dihydrate crystals from single diffusion gel technique

    Energy Technology Data Exchange (ETDEWEB)

    Rajendran, K.; Dale Keefe, C. [Department of Chemistry, Cape Breton University, Sydney, Nova Scotia (Canada)

    2010-09-15

    Calcium hydrogen phosphate dihydrate (CaHPO{sub 4}.2H{sub 2}O, CHPD) a dissolved mineral in urine is known to cause renal or bladder stones in both human and animals. Growth of CHPD or brushite using sodium metasilicate gel techniques followed by light and polarizing microscopic studies revealed its structural and morphological details. Crystal identity by powder x-ray diffraction confirmed the FT-IR and FT-Raman spectroscopic techniques as alternate methods for fast analysis of brushite crystals which could form as one type of renal stones. P-O-P asymmetric stretchings in both FT-IR (987.2, 874.1 and 792 cm{sup -1}) and FT-Raman (986.3 cm{sup -1}, 1057.6 cm{sup -1} and 875.2 cm{sup -1}) were found as characteristics of brushite crystals. Differential Scanning Calorimetry (DSC) analysis revealed brushite crystallization purity using gel method by studying their endothermic peaks. This study incorporated a multidisciplinary approach in characterizing CHPD crystals grown in vitro to help formulate prevention or dissolution strategy in controlling urinary stone growth. Initial studies with 0.2 M citric acid ions as controlling agent in the nucleation of brushite crystals further support the presented approach. (copyright 2010 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  20. Sol – Gel synthesis and characterization of magnesium peroxide nanoparticles

    International Nuclear Information System (INIS)

    Jaison, J; Chan, Y S; Ashok raja, C; Balakumar, S

    2015-01-01

    Magnesium peroxide is an excellent source of oxygen in agriculture applications, for instance it is used in waste management as a material for soil bioremediation to remove contaminants from polluted underground water, biological wastes treatment to break down hydrocarbon, etc. In the present study, sol-gel synthesis of magnesium peroxide (MgO 2 ) nanoparticles is reported. Magnesium peroxide is odourless; fine peroxide which releases oxygen when reacts with water. During the sol-gel synthesis, the magnesium malonate intermediate is formed which was then calcinated to obtain MgO 2 nanoparticles. The synthesized nanoparticles were characterized using Thermo gravimetric -Differential Thermal Analysis (TG- DTA), X-Ray Diffraction studies (XRD) and High Resolution Transmission Electron Microscope (HRTEM). Our study provides a clear insight that the formation of magnesium malonate during the synthesis was due to the reaction between magnesium acetate, oxalic acid and ethanol. In our study, we can conclude that the calcination temperature has a strong influence on particle size, morphology, monodispersity and the chemistry of the particles. (paper)