WorldWideScience

Sample records for entity solvothermal synthesis

  1. Solvothermal synthesis of high molecular weight dithienogermole ...

    Indian Academy of Sciences (India)

    Solvothermal synthesis of high molecular weight dithienogermole containing conjugated polymers. FEI-BAO ZHANG∗, SU-FANG LV, JIANG-XIONG JIANG and YONG NI∗. Key Laboratory of Organosilicon Chemistry and Material Technology of Ministry of Education, Hangzhou. Normal University, Hangzhou 310012, China.

  2. Solvothermal synthesis of high molecular weight dithienogermole ...

    Indian Academy of Sciences (India)

    dithiadiazole alternate polymers were synthesized by the solvothermal method. Optical properties and molecular weight were investigated by UV–Vis absorption spectroscopy and Gel Permeation Chromatography. Compared with the results achieved ...

  3. Solvothermal synthesis of cobalt oxides nanocrystals

    Science.gov (United States)

    Shao, Wenyao; Yan, Mengwen

    2017-05-01

    CoO and Co3O4 nanocrystals (NCs) were synthesized by a one-pot solvothermal reaction in the presence of the oxidant NaOH and the surfactant cetyltrimethyl ammonium bromide (CTAB). The as-prepared cobalt oxide nanoparticles are size uniformed and have good dispersibility and good crystallinity.

  4. Solvothermal synthesis and theoretical study of a polypyridium ...

    Indian Academy of Sciences (India)

    ... 1 was isolated from solvothermal synthesis of 4'-(4-pyridyl)-2,2':6',2'-terpyridine (pytpy) and trimesic acid (1,3,5-benzenetricarboxylic acid, H3BTC). It was characterized by element analysis, IR, TGA, XRD, X-ray single-crystal diffraction, and spectroscopy properties, together with quantum chemistry calculation of spectrum ...

  5. Solvothermal synthesis of InP quantum dots.

    Science.gov (United States)

    Nag, Angshuman; Sarma, D D

    2009-09-01

    We report an efficient and fast solvothermal route to prepare highly crystalline monodispersed InP quantum dots. This solvothermal route, not only ensures inert atmosphere, which is strictly required for the synthesis of phase pure InP quantum dots but also allows a reaction temperature as high as 430 degrees C, which is otherwise impossible to achieve using a typical solution chemistry; the higher reaction temperature makes the reaction more facile. This method also has a judicious control over the size of the quantum dots and thus in tuning the bandgap.

  6. Continuous-flow hydrothermal and solvothermal synthesis of inorganic nanomaterials

    OpenAIRE

    Starkey, Christopher L.

    2016-01-01

    Nanomaterials and nanotechnology are presently receiving high levels of interest which is aiding significant advancements to industrial and technological applications. New strategies towards nanoparticle synthesis are needed to produce high quality nanomaterials at industrially viable levels. This thesis presents the continuous flow hydrothermal and solvothermal synthesis (CFHSS) of a range of inorganic nanomaterials produced using a continuous-flow reactor designed at the University of Notti...

  7. Solvothermal synthesis and theoretical study of a polypyridium ...

    Indian Academy of Sciences (India)

    Abstract. The title compound (C9H3O6·C20H17N4)4·0.5H2O 1 was isolated from solvothermal synthesis of. 4 -(4-pyridyl)-2,2 :6 ,2 -terpyridine (pytpy) and trimesic acid (1,3,5-benzenetricarboxylic acid, H3BTC). It was characterized by element analysis, IR, TGA, XRD, X-ray single-crystal diffraction, and spectroscopy proper-.

  8. Solvothermal synthesis: a new route for preparing nitrides

    CERN Document Server

    Demazeau, G; Denis, A; Largeteau, A

    2002-01-01

    Solvothermal synthesis appears to be an interesting route for preparing nitrides such as gallium nitride and aluminium nitride, using ammonia as solvent. A nitriding additive is used to perform the reaction and, in the case of gallium nitride, is encapsulated by melt gallium. The syntheses are performed in the temperature range 400-800 deg. C and in the pressure range 100-200 MPa. The synthesized powders are characterized by x-ray diffraction and scanning electron microscopy. Finely divided gallium nitride GaN and aluminium nitride AlN, both with wurtzite-type structure, can be obtained by this route.

  9. Large pyramid shaped single crystals of BiFeO{sub 3} by solvothermal synthesis method

    Energy Technology Data Exchange (ETDEWEB)

    Sornadurai, D.; Ravindran, T. R.; Paul, V. Thomas; Sastry, V. Sankara [Condensed Matter Physics Division, Materials Science Group, Physical Metallurgy Division, Metallurgy and Materials Group, Indira Gandhi Centre for Atomic Research, Kalpakkam, Tamil Nadu (India); Condensed Matter Physics Division, Materials Science Group (India)

    2012-06-05

    Synthesis parameters are optimized in order to grow single crystals of multiferroic BiFeO{sub 3}. 2 to 3 mm size pyramid (tetrahedron) shaped single crystals were successfully obtained by solvothermal method. Scanning electron microscopy with EDAX confirmed the phase formation. Raman scattering spectra of bulk BiFeO3 single crystals have been measured which match well with reported spectra.

  10. Solvothermal Synthesis of Indium Telluride Nanowires and Its Photoelectrical Property.

    Science.gov (United States)

    Yan, Shancheng; Zhou, Liyan; Shi, Yi; Wang, Bojun; Wang, Junzhuan; Xu, Xin

    2015-05-01

    In this paper, 1D In2Te3 nanowires were synthesizes through a simple solvothermal approach. The morphology was first studied by scanning electron microscopy (SEM) and Transmission electron microscopy (TEM). From the results, the nanowires have a diameter from 100 to 200 nm and a length of dozens of microns. X-ray Diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and Raman spectrum were used to study the composition, crystal structures, and optical property. Based on the typical nanowire sample, experiment factors were changed to synthsize other samples in order to study the influence factors. A possible growth mechanism of the nanowires was proposed based on a series of experimental results. This material has a broad light detection range covering the UV-visible-NIR region from the photoelectrical test, which makes it potential for applications in photodetectors and solar cells.

  11. Synthesis of highly crystalline titania nanocrystals through solvothermal technique.

    Science.gov (United States)

    Ge, Lei; Yang, Ping; Cheng, Xin

    2014-04-01

    Highly crystalline rhombic TiO2 nanocrystals (NCs) were fabricated through a solvothermal technique in anhydrous ethanol. A Teflon cup with reaction agents including titanium (IV) isopropoxide, oleic acid (OA), oleylamine (OM), and anhydrous ethanol was put into a Teflon-lined stainless steel autoclave with ethanol and water for the purpose of controlling the hydrolytic reaction of Ti precursors. Water vapor generated from the mixture of water and ethanol was as a hydrolysis agent and oleic acid and oleylamine were as two distinct capping surfactants which have different binding strengths to control the growth of the TiO2 NCs. The molar ratios of oleic acid/oleylamine play a crucial role for the size and morphology of TiO2 NCs created through hydrolytic and nonhydrolytic processes. Highly crystalline rhombic TiO2 NCs were fabricated by combining hydrolytic and nonhydrolytic sol-gel reactions of titanium (IV) isopropoxide using a molar ratio of Ti precursors/OA/OM of 1/2/3 at 180 degrees C for 22 h. The transmission electron microscopic observations indicated that the rhombic TiO2 NCs have a uniform size distribution under optimal preparation conditions. The size and size distribution of the rhombic TiO2 NCs were adjusted by adding OM to the reaction mixture as a cosurfactant together with OA.

  12. Indium telluride nanotubes: Solvothermal synthesis, growth mechanism, and properties

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Liyan [National Laboratory of Solid State Microstructures, School of Electronic Science and Engineering, Nanjing University, Nanjing 210093 (China); Yan, Shancheng, E-mail: yansc@njupt.edu.cn [National Laboratory of Solid State Microstructures, School of Electronic Science and Engineering, Nanjing University, Nanjing 210093 (China); School of Geography and Biological Information, Nanjing University of Posts and Telecommunications, Nanjing 210046 (China); Lu, Tao; Shi, Yi; Wang, Jianyu [National Laboratory of Solid State Microstructures, School of Electronic Science and Engineering, Nanjing University, Nanjing 210093 (China); Yang, Fan [School of Geography and Biological Information, Nanjing University of Posts and Telecommunications, Nanjing 210046 (China)

    2014-03-15

    A convenient solvothermal approach was applied for the first time to synthesize In{sub 2}Te{sub 3} nanotubes. The morphology of the resultant nanotubes was studied by scanning electron microscopy and transmission electron microscopy. Nanotubes with a relatively uniform diameter of around 500 nm, tube wall thickness of 50–100 nm, and average length of tens of microns were obtained. X-ray diffraction, X-ray photoelectron spectroscopy, and Raman spectroscopy were used to study the crystal structures, composition, and optical properties of the products. To understand the growth mechanism of the In{sub 2}Te{sub 3} nanotubes, we studied the influences of temperature, reaction time, and polyvinylpyrrolidone (PVP) and ethylene diamine (EDA) dosages on the final products. Based on the experimental results, a possible growth mechanism of In{sub 2}Te{sub 3} nanotubes was proposed. In this mechanism, TeO{sub 3}{sup −2} is first reduced to allow nucleation. Circumferential edges of these nucleated molecules attract further deposition, and nanotubes finally grow rapidly along the c-axis and relatively slowly along the circumferential direction. The surface area of the products was determined by BET and found to be 137.85 m{sup 2} g{sup −1}. This large surface area indicates that the nanotubes may be suitable for gas sensing and hydrogen storage applications. The nanotubes also showed broad light detection ranging from 300 nm to 1100 nm, which covers the UV–visible–NIR regions. Such excellent optical properties indicate that In{sub 2}Te{sub 3} nanotubes may enable significant advancements in new photodetection and photosensing applications. -- Graphical abstract: A convenient solvothermal approach was applied to synthesize In{sub 2}Te{sub 3} nanotubes, which has not been reported in the literature for our knowledge. Surface area of this material is 137.85 m{sup 2} g{sup −1} from the BET testing, and such a high value makes it probably suitable for gas sensing and

  13. Solvothermal synthesis of tetravalent uranium with isophthalate or pyromellitate ligands

    Energy Technology Data Exchange (ETDEWEB)

    Falaise, Clement; Delille, Jason; Volkringer, Christophe; Loiseau, Thierry [Contribution from Unite de Catalyse et Chimie du Solide (UCCS) - UMR CNRS 8181, Universite de Lille, USTL-ENSCL, Villeneuve d' Ascq (France)

    2015-06-15

    Three new coordination polymers bearing tetravalent uranium have been isolated with the O-donor ligands such as isophthalate (1,3-bdc) or pyromellitate (btec). The compounds 1 and 3 have been solvothermally synthesized in N,N-dimethylformamide (DMF). The crystal structure of U(1,3-bdc){sub 2}(DMF) (1) is built up from discrete tricapped trigonal-primastic UO{sub 9} units, for which one carbonyl oxygen atom from DMF is bound to uranium. The connection of the UO{sub 9} units with the isophthalate linkers occurs in a chelating and bidentate fashion and gives rise to the formation of a 3D framework, delimiting narrow channels running along the [101] direction. Upon heating, the DMF molecules are removed, generating the second phase U(1,3-bdc){sub 2} (2) compound, closely related to 1. Indeed, the coordination environment of uranium is reduced to eight with a distorted square-antiprismatic geometry. This transition induces the relative shrinkage of the network (ΔV = 23 %). The structure of the compound U(btec)(DMF){sub 2} (3) also exhibits a 3D framework composed of an isolated bicapped square-antiprismatic UO{sub 10} unit, for which two carbonyl oxygen atoms from DMF are bonded to uranium. Pyromellitate ensures the connection of the UO{sub 10} units through the carboxylate arms in a chelating mode. This results in the formation of a network with diamond-shaped channels, developed along the c axis and encapsulating the DMF molecules. In contrast to 1, no stable phase is observed upon removing the DMF species by heating. (Copyright copyright 2015 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  14. Deep eutectic-solvothermal synthesis of nanostructured ceria

    National Research Council Canada - National Science Library

    Oliver S Hammond; Karen J Edler; Daniel T Bowron; Laura Torrente-murciano

    2017-01-01

    .... Here we report the synthesis of nanostructured ceria using the green Deep Eutectic Solvent reline, which allows morphology and porosity control in one of the less energy-intensive routes reported to date...

  15. A simple solvothermal synthesis of MFe 2O 4 ( M=Mn, Co and Ni) nanoparticles

    Science.gov (United States)

    Yáñez-Vilar, S.; Sánchez-Andújar, M.; Gómez-Aguirre, C.; Mira, J.; Señarís-Rodríguez, M. A.; Castro-García, S.

    2009-10-01

    Nanoparticles of MFe 2O 4 ( M=Mn, Co and Ni), with diameters ranging from 5 to 10 nm, have been obtained through a solvothermal method. In this synthesis, an alcohol (benzyl alcohol or hexanol) is used as both a solvent and a ligand; it is not necessary, therefore, to add a surfactant, simplifying the preparation of the dispersed particles. We have studied the influence of the synthetic conditions (temperature, time of synthesis and nature of solvent) on the quality of the obtained ferrites and on their particle size. In this last aspect, we have to highlight that the solvent plays an important role on the particle size, obtaining the smallest diameters when hexanol was used as a solvent. In addition, the magnetic properties of the obtained compounds have been studied at room temperature (RT). These compounds show a superparamagnetic behaviour, as was expected for single domain nanoparticles, and good magnetization values. The maxima magnetization values of the MFe 2O 4 samples are quite high for such small nanoparticles; this is closely related to the high crystallinity of the particles obtained by the solvothermal method.

  16. Solvothermal synthesis and analysis of Bi{sub 1-x}Sb{sub x} nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Sumithra, S.; Misra, D.K.; Wei, C. [Advanced Materials Research Institute, University of New Orleans, New Orleans, LA 70148 (United States); Gabrisch, H. [GKSS Research Center, Institute of Materials Research, Geesthacht (Germany); Poudeu, P.F.P. [Advanced Materials Research Institute, University of New Orleans, New Orleans, LA 70148 (United States); Department of Chemistry, University of New Orleans, New Orleans, LA 70148 (United States); Stokes, K.L., E-mail: klstokes@uno.edu [Advanced Materials Research Institute, University of New Orleans, New Orleans, LA 70148 (United States); Department of Physics, University of New Orleans, New Orleans, LA 70148 (United States)

    2011-02-25

    Bismuth-antimony alloy nanoparticles have been synthesized by a facile solvothermal method using N,N-dimethylformamide and ethylene glycol as solvent/reducing agent; BiCl{sub 3}, SbCl{sub 3} and Bi(NO{sub 3}){sub 3} as precursors; and citric acid as a surface modifier/stabilizing agent. The particle size and size distribution of Bi nanoparticles were analyzed as a function of the synthesis conditions: molar ratio of precursor to surfactant, precursor concentration and reducing agent. Synthesis of Sb and Bi{sub 0.88}Sb{sub 0.12} under similar conditions was also investigated. The phase purity of nanoparticles was confirmed from X-ray diffraction and thermogravimetry and the nanoparticle morphology was investigated by transmission electron microscopy. A case study of Bi nanoparticles with detailed analysis of the particle morphology and size distribution of the nanoparticles is reported.

  17. Low-temperature solvothermal synthesis of EuS hollow microspheres

    Energy Technology Data Exchange (ETDEWEB)

    Peng, Yong; Wang, Hong; Li, Peng; Fu, Yao, E-mail: fuyaozn@126.com; Xing, Mingming; Jiang, Tao; Luo, Xixian, E-mail: luoxixiandl@126.com

    2014-09-15

    Graphical abstract: Synthesis of EuS hollow microspheres at low-temperature via solvothermal method for the first time. - Highlights: • We adopt an improved method to synthesise the (Phen)Eu(Et{sub 2}CNS{sub 2}){sub 3} in deionized water. • We have successfully synthesised the EuS hollow microsphere at 230 °C in acetonitrile. • The price of acetonitrile is more inexpensive, so the price of preparation was reduced. - Abstract: EuS crystals are synthesized by low-temperature solvothermal decomposition of the single source precursor complex (Phen)Eu(Et{sub 2}CNS{sub 2}){sub 3} in acetonitrile. X-ray powder diffraction, scanning electron microscopy, granulocyte diameter statistical analysis, surface energy-dispersive X-ray spectroscopy analysis, and UV–vis absorption spectroscopy are used to characterize the structure and properties of the obtained EuS crystals. The results show that the formed EuS crystals are uniform hollow microspheres with a typical cubic phase structure of rock salt and the average particle size of 2.01 μm. The mechanisms for the thermal decomposition of the precursor complex and the formation of the EuS hollow microspheres are postulated based on the experimental observations and previous reports.

  18. High-Quality ZnCdS Nanosheets Prepared Using Solvothermal Synthesis

    Directory of Open Access Journals (Sweden)

    M. A. Mahdi

    2013-01-01

    Full Text Available For the first time, ZnxCd1-xS nanosheets with different Zn and Cd ion concentrations were prepared using solvothermal synthesis at 200°C for 4 and 24 h. The crystalline structure of the nanosheets was wurtzite. The optical band gaps of the nanosheets increased with increasing Zn ratio; this increase is consistent with the band gaps estimated using Vegard’s formula. The photoluminescence spectra for the 24 h nanosheets had higher emission intensities than those for the 4 h nanosheets. The emission band corresponding to intrinsic near-band-edge emission and a broad peak associated with extrinsic deep-level emission were observed in the photoluminescence spectra.

  19. 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.

  20. Size control mechanism of ZnO nanoparticles obtained in microwave solvothermal synthesis

    Science.gov (United States)

    Wojnarowicz, Jacek; Chudoba, Tadeusz; Koltsov, Iwona; Gierlotka, Stanislaw; Dworakowska, Sylwia; Lojkowski, Witold

    2018-02-01

    The aim of the paper is to explain the mechanism of zinc oxide (ZnO) nanoparticle (NP) size control, which enables the size control of ZnO NPs obtained in microwave solvothermal synthesis (MSS) within the size range between circa 20 and 120 nm through the control of water content in the solution of zinc acetate in ethylene glycol. Heavy water was used in the tests. The mechanism of ZnO NPs size control was explained, discussed and experimentally verified. The discovery and investigation of this mechanism was possible by tracking the fate of water molecules during the whole synthesis process. All the synthesis products were identified. It was indicated that the MSS of ZnO NPs proceeded through the formation and conversion of intermediates such as Zn5(OH)8(CH3COO)2 · xH2O. Esters and H2O were the by-products of the MSS reaction of ZnO NPs. We justified that the esterification reaction is the decisive stage that is a prerequisite of the formation of ZnO NPs. The following parameters of the obtained ZnO NPs and of the intermediate were determined: pycnometric density, specific surface area, phase purity, average particles size, particles size distribution and chemical composition. The ZnO NPs morphology and structure were determined using scanning electron microscopy.

  1. Solvothermal synthesis and thermoelectric property of undoped and indium doped lead telluride nanoparticles

    Science.gov (United States)

    Kadel, Kamal; Li, Wenzhi

    2013-03-01

    Undoped and indium (In) doped lead telluride (PbTe) nanostructures were synthesized via solvothermal/hydrothermal route. The crystallinity of the as-prepared un-doped and In-doped PbTe sample were examined by X-ray diffraction (XRD) which indicated the formation of face centered single phase cubic PbTe. Lattice constant calculation from XRD pattern revealed the formation of un-doped and In-doped PbTe crystals with almost similar size. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) examinations indicated that undoped and In-doped PbTe nanostructures were mostly cubically shaped and highly crystalline. The effect of the synthesis temperature on the structure and morphology of undoped PbTe was also investigated; it was found that the particle size increased with the synthesis temperature. Thermoelectric property of as-synthesized lead telluride sample was also investigated. This work is supported by the National Science Foundation under the grant DMR- 0548061.

  2. Swift tuning from spherical molybdenum microspheres to hierarchical molybdenum disulfide nanostructures by switching from solvothermal to hydrothermal synthesis route

    Science.gov (United States)

    Qureshi, Nilam; Arbuj, Sudhir; Shinde, Manish; Rane, Sunit; Kulkarni, Milind; Amalnerkar, Dinesh; Lee, Haiwon

    2017-09-01

    Herein, we report the synthesis of metallic molybdenum microspheres and hierarchical MoS2 nanostructures by facile template-free solvothermal and hydrothermal approach, respectively. The morphological transition of the Mo microspheres to hierarchical MoS2 nanoflower architectures is observed to be accomplished with change in solvent from ethylenediamine to water. The resultant marigold flower-like MoS2 nanostructures are few layers thick with poor crystallinity while spherical ball-like molybdenum microspheres exhibit better crystalline nature. This is the first report pertaining to the synthesis of Mo microspheres and MoS2 nanoflowers without using any surfactant, template or substrate in hydro/solvothermal regime. It is opined that such nanoarchitectures of MoS2 are useful candidates for energy related applications such as hydrogen evolution reaction, Li ion battery and pseudocapacitors. Inquisitively, metallic Mo can potentially act as catalyst as well as fairly economical Surface Enhanced Raman Spectroscopy (SERS) substrate in biosensor applications.

  3. Solvothermal synthesis of gallium-indium-zinc-oxide nanoparticles for electrolyte-gated transistors.

    Science.gov (United States)

    Santos, Lídia; Nunes, Daniela; Calmeiro, Tomás; Branquinho, Rita; Salgueiro, Daniela; Barquinha, Pedro; Pereira, Luís; Martins, Rodrigo; Fortunato, Elvira

    2015-01-14

    Solution-processed field-effect transistors are strategic building blocks when considering low-cost sustainable flexible electronics. Nevertheless, some challenges (e.g., processing temperature, reliability, reproducibility in large areas, and cost effectiveness) are requirements that must be surpassed in order to achieve high-performance transistors. The present work reports electrolyte-gated transistors using as channel layer gallium-indium-zinc-oxide nanoparticles produced by solvothermal synthesis combined with a solid-state electrolyte based on aqueous dispersions of vinyl acetate stabilized with cellulose derivatives, acrylic acid ester in styrene and lithium perchlorate. The devices fabricated using this approach display a ION/IOFF up to 1 × 10(6), threshold voltage (VTh) of 0.3-1.9 V, and mobility up to 1 cm(2)/(V s), as a function of gallium-indium-zinc-oxide ink formulation and two different annealing temperatures. These results validates the usage of electrolyte-gated transistors as a viable and promising alternative for nanoparticle based semiconductor devices as the electrolyte improves the interface and promotes a more efficient step coverage of the channel layer, reducing the operating voltage when compared with conventional dielectrics gating. Moreover, it is shown that by controlling the applied gate potential, the operation mechanism of the electrolyte-gated transistors can be modified from electric double layer to electrochemical doping.

  4. A Facile Solvothermal Method for Synthesis of CuInS2 Nanostructures

    Directory of Open Access Journals (Sweden)

    M. Mousavi-Kamazani

    2012-09-01

    Full Text Available CuInS2 nanostructures were  synthesized  via  a  simple  surfactant-free solvothermal  route.  In  this  synthesis,  thiosemicarbazide  and thioglycolic acid were used as sulfur sources. The effects of different parameters such as type of precursor and time on the morphology and particle  size  of  the  samples  have  been  investigated.  The nanostructures  were  characterized  by  means  of  X-ray  diffraction (XRD,  scanning  electron microscopy  (SEM,  energy-dispersive X- ray  analysis  (EDX,  Fourier  transform  infrared  (FT-IR  and photoluminescence  (PL  spectroscopy.  The  fill  factor  (FF,  open circuit voltage  (Voc, and  short circuit current  (Isc were obtained by I–V characterization.

  5. Surfactant-assisted solvothermal synthesis of pure nickel submicron spheres with microwave-absorbing properties

    Science.gov (United States)

    Guo, Heng; Pu, Bingxue; Chen, Haiyuan; Yang, Jin; Zhou, Yajun; Yang, Jian; Bismark, Boateng; Li, Handong; Niu, Xiaobin

    2016-07-01

    Pure metallic nickel submicron spheres (Ni-SSs), flower-like nickel nanoflakes, and hollow micrometer-sized nickel spheres/tubes were controllably synthesized by a facile and efficient one-step solvothermal method with no reducing agent. The characteristics of these nickel nanostructures include morphology, structure, and purification. Possible synthesis mechanisms were discussed in detail. The resultant Ni-SSs had a wide diameter distribution of 200~800 nm through the aggregation of small nickel nanocrystals. The ferromagnetic behaviors of Ni-SSs investigated at room temperature showed high coercivity values. Furthermore, the microwave absorption properties of magnetic Ni-SSs were studied in the frequency range of 0.5-18.0 GHz. The minimum reflection loss reached -17.9 dB at 17.8 GHz with a thin absorption thickness of 1.2 mm, suggesting that the submicron spherical structures could exhibit excellent microwave absorption properties. More importantly, this one-pot synthesize route provides a universal and convenient way for preparation of larger scale pure Ni-SSs, showing excellent microwave absorption properties.

  6. Microwave solvothermal synthesis and characterization of manganese-doped ZnO nanoparticles

    Directory of Open Access Journals (Sweden)

    Jacek Wojnarowicz

    2016-05-01

    Full Text Available Mn-doped zinc oxide nanoparticles were prepared by using the microwave solvothermal synthesis (MSS technique. The nanoparticles were produced from a solution of zinc acetate dihydrate and manganese(II acetate tetrahydrate using ethylene glycol as solvent. The content of Mn2+ in Zn1−xMnxO ranged from 1 to 25 mol %. The following properties of the nanostructures were investigated: skeleton density, specific surface area (SSA, phase purity (XRD, lattice parameters, dopant content, average particle size, crystallite size distribution, morphology. The average particle size of Zn1−xMnxO was determined using Scherrer’s formula, the Nanopowder XRD Processor Demo web application and by converting the specific surface area results. X-ray diffraction of synthesized samples shows a single-phase wurtzite crystal structure of ZnO without any indication of additional phases. Spherical Zn1−xMnxO particles were obtained with monocrystalline structure and average particle sizes from 17 to 30 nm depending on the content of dopant. SEM images showed an impact of the dopant concentration on the morphology of the nanoparticles.

  7. A Simple and High Yield Solvothermal Synthesis of Uniform Silver Nanowires with Controllable Diameters

    Directory of Open Access Journals (Sweden)

    M. Khademalrasool

    2015-10-01

    Full Text Available Silver nanowires were synthesized by solvothermal method through reducing silver nitrate (AgNO3 with ethylene glycol (EG in the presence of polyvinylpyrrolidone (PVP. In order to prevent the agglomeration of Ag+ in the initial Ag seeds formation, sodium chloride (NaCl was added into the solution to form AgCl colloids. By dissolving AgCl in the late stages, Ag+ ions were released into the solution. So the diameters of silver nanowires could be controlled by modifying the PVP concentration. The effect of reaction time, reaction temperature, and for first time purity of EG over the shape of resulted silver nanowires were investigated. The wire, sphere and tree-like nanostructures were formed with changing these parameters. The structural and optical properties of the silver nanostructures were studied by X-ray diffraction (XRD, scanning electron microscopy (SEM, field emission scanning electron microscopy (FESEM, Fourier transform infrared spectroscopy (FTIR, and UV–visible absorption spectrophotometer. In order to synthesis silver nanowires with smaller diameters and longer lengths, the optimum molar ratio of PVP/AgNO3, reaction time, reaction temperature, and EG purity were found to be 1.5, 2.5 h, 160 °C, and 99.5%, respectively.

  8. Synthesis of Framework Isomer MOFs Containing Zinc and 4-Tetrazolyl Benzenecarboxylic Acid via a Structure Directing Solvothermal Approach

    Directory of Open Access Journals (Sweden)

    Carlos Ordonez

    2015-04-01

    Full Text Available The solvothermal synthesis of framework isomers was carried out using the hybrid carboxylate and tetrazolate functional ligand, 4-tetrazolyl benzenecarboxylic acid (H2TBC, TBC = 4-tetrazolyl benzenecarboxylate and zinc. H2TBC was also synthesized with the solvothermal approach, and is referred herein as structure 1. Using single-crystal X-ray diffraction, we found that the tetrazolate groups of TBC show an unusual “opposite-on” coordination mode with zinc. Three previously characterized metal-organic frameworks (MOFs were obtained by systematically changing the solvents of the H2TBC-Zn reaction, (1 ZnTBC, 2, which has a non-porous structure; (2 Zn2(TBC2(H2O, 3, which has an amphiphilic pore structure and (3 Zn2(TBC2{guest}, 4, which is porous and has channels containing uncoordinated N heteroatoms. Fluorescence spectra of 4 reveal a strong blue emission mainly from the TBC ligands.

  9. One-pot synthesis of α-Fe2O3 nanospheres by solvothermal method

    National Research Council Canada - National Science Library

    Wang, Caihua; Cui, Yumin; Tang, Kaibin

    2013-01-01

    We have successfully prepared α-Fe2O3 nanospheres by solvothermal method using 2-butanone and water mixture solvent for the first time, which were about 100 nm in diameter and composed of very small nanoparticle...

  10. Solvothermal synthesis of Ag hybrid BiPO4 heterostructures with enhanced photodegradation activity and stability.

    Science.gov (United States)

    Huang, Chang-Wei; Wu, Mei-Yao; Lin, Yang-Wei

    2017-03-15

    In this study, Ag hybrid BiPO4 (Ag/BiPO4) heterostructures were synthesized using a solvothermal method. The morphologies and optical properties of the Ag/BiPO4 heterostructures were drastically different from those of BiPO4 and were highly dependent on the AgNO3:BiPO4 weight percent during the synthesis. The three formulated heterostructures were evaluated for their photocatalytic degradation of methylene blue (MB) under UV light illumination; the 0.5%Ag/BiPO4 heterostructure was observed to result in 99% degradation of MB within 60min, a remarkably higher level of photodegradation activity than the levels caused by TiO2 and BiPO4. Furthermore, even after use for five cycles of MB degradation, the 0.5%Ag/BiPO4 heterostructure showed no observable loss in photodegradation activity and no change in XRD patterns, demonstrating its chemical and structural stability. According to the results of a systematic experimental investigation, the enhanced photodegradation activity of this Ag/BiPO4 heterostructure could be ascribed to the high position of its valence band and the highly efficient separation of photogenerated electrons and holes. Moreover, hydroxyl radicals and holes were found to be the major reactive species. Successful photodegradation of standard dye solutions, including acid blue 1, methyl orange, fast green, rhodamine B, rhodamine 6G, and MB, in real water samples was demonstrated with the 0.5%Ag/BiPO4 heterostructure, providing clear evidence of its utility for treating waste water containing organic dyes. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. Paramagnetism of cobalt-doped ZnO nanoparticles obtained by microwave solvothermal synthesis

    Directory of Open Access Journals (Sweden)

    Jacek Wojnarowicz

    2015-09-01

    Full Text Available Zinc oxide nanopowders doped with 1–15 mol % cobalt were produced by the microwave solvothermal synthesis (MSS technique. The obtained nanoparticles were annealed at 800 °C in nitrogen (99.999% and in synthetic air. The material nanostructure was investigated by means of the following techniques: X-ray diffraction (XRD, helium pycnometry density, specific surface area (SSA, inductively coupled plasma optical emission spectrometry (ICP-OES, extended X-ray absorption fine structure (EXAFS spectroscopy, scanning electron microscopy (SEM, energy dispersive X-ray spectroscopy (EDS and with magnetometry using superconducting quantum interference device (SQUID. Irrespective of the Co content, nanoparticles in their initial state present a similar morphology. They are composed of loosely agglomerated spherical particles with wurtzite-type crystal structure with crystallites of a mean size of 30 nm. Annealing to temperatures of up to 800 °C induced the growth of crystallites up to a maximum of 2 μm in diameter. For samples annealed in high purity nitrogen, the precipitation of metallic α-Co was detected for a Co content of 5 mol % or more. For samples annealed in synthetic air, no change of phase structure was detected, except for precipitation of Co3O4 for a Co content of 15 mol %. The results of the magentometry investigation indicated that all as-synthesized samples displayed paramagnetic properties with a contribution of anti-ferromagnetic coupling of Co–Co pairs. After annealing in synthetic air, the samples remained paramagnetic and samples annealed under nitrogen flow showed a magnetic response under the influences of a magnetic field, likely related to the precipitation of metallic Co in nanoparticles.

  12. Water-assisted and surfactant-free synthesis of cobalt ferrite nanospheres via solvothermal method

    Energy Technology Data Exchange (ETDEWEB)

    Bi, Yiqing [CAS Laboratory of Nanosystem and Hierarchical Fabrication, National Center for Nanoscience and Technology, Beijing 100190 (China); University of the Chinese Academy of Sciences, Beijing 100049 (China); Ren, Yanan [CAS Laboratory of Nanosystem and Hierarchical Fabrication, National Center for Nanoscience and Technology, Beijing 100190 (China); Bi, Feng [CAS Laboratory of Nanosystem and Hierarchical Fabrication, National Center for Nanoscience and Technology, Beijing 100190 (China); University of the Chinese Academy of Sciences, Beijing 100049 (China); He, Tao, E-mail: het@nanoctr.cn [CAS Laboratory of Nanosystem and Hierarchical Fabrication, National Center for Nanoscience and Technology, Beijing 100190 (China)

    2015-10-15

    With ethylene glycol as the solvent, monodispersed cobalt ferrite nanospheres were prepared via a solvothermal method assisted by water. The samples were mainly characterized by X-ray diffraction, scanning electron microscope, and transmission electron microscope. The size of as-prepared products ranges from 10 nm to 200 nm. Size distribution and chemical composition were controlled by the amount of water and pH value in the reaction system. More important, suitable amount of water can avoid the use of surfactant. - Highlights: • Cobalt ferrite nanospheres were synthesized via solvothermal method assisted by water. • An introduction of suitable amount of water can avoid the use of surfactant. • The pH value of the precursor can be used to adjust the product composition.

  13. Synthesis of Antimony Nanotubes via Facile Template-Free Solvothermal Reactions.

    Science.gov (United States)

    Li, Ruxue; Wang, Xiaohua; Wang, Xinwei; Zhang, Haoran; Pan, Jingxin; Tang, Jilong; Fang, Dan; Ma, Xiaohui; Li, Yongfeng; Yao, Bin; Fan, Jie; Wei, Zhipeng

    2016-12-01

    Uniform antimony (Sb) nanotubes were successfully synthesized via a facile solvothermal method without the need for any surfactants or templates. The Sb nanotubes are confirmed to be pure rhombohedral phase and have better crystallinity. These nanotubes show middle-hollow and open-ended structures, as well as multi-walled structures with the wall thickness of about 10 nm. Also, they have an average size of the diameter of about 50 nm and the length of about 350 nm. On the basis of the structural and morphological studies, a possible rolling mechanism is proposed to explain the formation of Sb nanotubes. It is expected that uniform Sb nanotubes can further be used in wide applications. Graphical Abstract A possible rolling-formation mechanism is proposed for forming pure rhombhedral phase and high crystallinity antimony nanotubes without any surfactants or templates via a facile solvothermal method.

  14. Solvothermal synthesis of hierarchical TiO2 nanostructures with tunable morphology and enhanced photocatalytic activity

    Science.gov (United States)

    Fan, Zhenghua; Meng, Fanming; Zhang, Miao; Wu, Zhenyu; Sun, Zhaoqi; Li, Aixia

    2016-01-01

    This paper presents controllable growth and photocatalytic activity of TiO2 hierarchical nanostructures by solvothermal method at different temperatures. It is revealed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) that the morphology of TiO2 can be effectively controlled as rose-like, chrysanthemum-like and sea-urchin-like only changing solvothermal temperature. BET surface area analysis confirms the presence of a mesoporous network in all the nanostructures, and shows high surface area at relatively high temperature. The photocatalytic activities of the photocatalysts are evaluated by the photodegradation of RhB under UV light irradiation. The TiO2 samples exhibit high activity on the photodegradation of RhB, which is higher than that of the commercial P25. The enhancement in photocatalytic performance can be attributed to the synergetic effect of the surface area, crystallinity, band gap and crystalline size.

  15. One-pot synthesis of ?-Fe2O3 nanospheres by solvothermal method

    OpenAIRE

    Wang, Caihua; Cui, Yumin; Tang, Kaibin

    2013-01-01

    We have successfully prepared ?-Fe2O3 nanospheres by solvothermal method using 2-butanone and water mixture solvent for the first time, which were about 100 nm in diameter and composed of very small nanoparticles. The as-prepared samples were characterized using X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. The results showed that the product was ?-Fe2O3 nanosphere, and the temperature was an important factor on the formation of ?-Fe2O3 nanospheres.

  16. Facile Solvothermal Synthesis of BiOCl/ZnO Heterostructures with Enhanced Photocatalytic Activity

    Directory of Open Access Journals (Sweden)

    Yong-Fang Li

    2014-01-01

    Full Text Available Well-defined nanosheet-assembled (BiOClx(ZnO1−x nanoflowers were synthesized by a solvothermal method. It was found that ZnO nanoparticles were anchored on the flower-like BiOCl nanostructures, as demonstrated by varying the initial compositions of the Bi precursor and the volume ratios of mixed solvents (ethylene glycol to water. The as-prepared (BiOCl0.6(ZnO0.4 nanocomposites showed enhanced photocatalytic activity toward rhodamine B degradation under ultraviolet (UV irradiation. And the photocatalytic mechanism was discussed in detail.

  17. Solvothermal Synthesis of Well-Disperse ZnS Nanorods with Efficient Photocatalytic Properties

    Directory of Open Access Journals (Sweden)

    Yun Chen

    2012-01-01

    Full Text Available Well-disperse short-range-ordered ZnS nanorods with efficient photocatalytic property for photodegradation of Rhodamin B have been successfully synthesized through a solvothermal method. Solvent used can be recovered and reused, which makes the route environment-friendly. Dodecylamine was found effective in organizing nanorods to ordered monolayer. Characterization showed that these nanorods were uniform with the diameter of about 3 nm and length of nearly 30 nm. And it is expected that these monodisperse ZnS nanorods have potential applications in electroluminescence materials.

  18. A Simple and Facile Solvothermal Synthesis of Hierarchical PbS Microstars with Multidendritic Arms and Their Optical Properties

    Directory of Open Access Journals (Sweden)

    Yong-Fang Li

    2015-01-01

    Full Text Available A simple and facile approach was developed in the solvothermal synthesis of hierarchical PbS microstars with multidendritic arms, which were characterized by X-ray diffraction (XRD, scanning electron microscopy (SEM, transmission electron microscopy (TEM, Fourier transform infrared (FT-IR and photoluminescence (PL spectroscopy. The morphologies of PbS products were strongly determined by the reaction time and temperature, the ratios of the precursors, and the mixed solvent with various components, and thereby their possible formation mechanism was discussed in some detail. The as-prepared PbS crystals displayed a sharp and strong photoluminescent peak at 437 nm at room temperature. It has potential and practical applications in photoluminescence, photovoltaics, IR photodetectors, electroluminescence, and solar absorbers.

  19. Solvothermal synthesis and characterization of functionalized graphene sheets (FGSs)/magnetite hybrids

    Energy Technology Data Exchange (ETDEWEB)

    Zhan Yingqing; Meng Fanbin; Yang Xulin; Zhao Rui [Research Branch of Functional Materials, Institute of Microelectronic and Solid State Electronic, University of Electronic Science and Technology of China, Chengdu 610054 (China); Liu Xiaobo, E-mail: liuxb@uestc.edu.cn [Research Branch of Functional Materials, Institute of Microelectronic and Solid State Electronic, University of Electronic Science and Technology of China, Chengdu 610054 (China)

    2011-09-25

    Highlights: > Functionalized graphene sheets/Fe{sub 3}O{sub 4} hybrids were synthesized through solvothermal method. > The denseness, size and crystallinity of magnetite formed on FGSs can be altered. > The as-prepared hybrids exhibited high resistivity and saturation magnetization. > The magnetic loss was caused mainly by ferromagnetic natural resonance. - Abstract: Novel functionalized graphene sheets (FGSs)/Fe{sub 3}O{sub 4} hybrids were synthesized through a facile one-step solvothermal method using FeCl{sub 3} as iron source, ethylene glycol as the reducing agent and graphene nanosheets as templates. The morphology, composition and phase structure of as-prepared hybrid materials were characterized by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and transmission electron microscopy (TEM). These results showed that denseness, size and crystallinity of magnetite can be altered by controlling the reaction parameters. Magnetization measurement indicated that both coercivity and saturation magnetization increased linearly with increasing magnetite concentration in hybrid materials. The measured relative complex permittivity indicated that a high resistivity existed in the FGSs/Fe{sub 3}O{sub 4} inorganic hybrids. The magnetic loss was caused mainly by ferromagnetic natural resonance, which is in agreement with the Kittel equation. The novel inorganic hybrid materials are believed to have potential applications in the microwave absorbing performances.

  20. Morphology-Controlled Synthesis Of SrTiO3 Nanocube By Capping Agent-Assisted Solvothermal Method

    Directory of Open Access Journals (Sweden)

    Yulia Eka Putri

    2016-05-01

    Full Text Available The synthesis of SrTiO3 nanocubes have been carried out by solvothermal process using cetyl trimethyl ammonium bromide (CTAB as capping agent to control the particles morphology. The condition of the synthesis was obtained at 160 ºC for 24 hours with molar ratio of SrTiO3 and capping agent was 1 : 1. The X-ray diffraction (XRD pattern shows that SrTiO3 adopts a perovskite structure with a higher intensity of 110 at 2q:32.33º and the crystallite size calculated from FWHM was found to be 41 nm. Fourier transform infrared (FTIR spectrum shows a shift in particular absorption band attributed the interaction between SrTiO3 particles surface and the head group of CTAB molecules. Transmission electron microscopy (TEM image shows the cubic-like particles of SrTiO3, this indicatesthat CTAB successfully functions as capping agent on the synthesis of SrTiO3.

  1. Solvothermal synthesis and thermoelectric properties of indium telluride nanostring-cluster hierarchical structures

    Directory of Open Access Journals (Sweden)

    Zhang Haiqian

    2011-01-01

    Full Text Available Abstract A simple solvothermal approach has been developed to successfully synthesize n-type α-In2Te3 thermoelectric nanomaterials. The nanostring-cluster hierarchical structures were prepared using In(NO33 and Na2TeO3 as the reactants in a mixed solvent of ethylenediamine and ethylene glycol at 200°C for 24 h. A diffusion-limited reaction mechanism was proposed to explain the formation of the hierarchical structures. The Seebeck coefficient of the bulk pellet pressed by the obtained samples exhibits 43% enhancement over that of the corresponding thin film at room temperature. The electrical conductivity of the bulk pellet is one to four orders of magnitude higher than that of the corresponding thin film or p-type bulk sample. The synthetic route can be applied to obtain other low-dimensional semiconducting telluride nanostructures. PACS: 65.80.-g, 68.35.bg, 68.35.bt

  2. Solvothermal synthesis and thermoelectric properties of indium telluride nanostring-cluster hierarchical structures

    Science.gov (United States)

    Tai, Guo'an; Miao, Chunyang; Wang, Yubo; Bai, Yunrui; Zhang, Haiqian; Guo, Wanlin

    2011-12-01

    A simple solvothermal approach has been developed to successfully synthesize n-type α-In2Te3 thermoelectric nanomaterials. The nanostring-cluster hierarchical structures were prepared using In(NO3)3 and Na2TeO3 as the reactants in a mixed solvent of ethylenediamine and ethylene glycol at 200°C for 24 h. A diffusion-limited reaction mechanism was proposed to explain the formation of the hierarchical structures. The Seebeck coefficient of the bulk pellet pressed by the obtained samples exhibits 43% enhancement over that of the corresponding thin film at room temperature. The electrical conductivity of the bulk pellet is one to four orders of magnitude higher than that of the corresponding thin film or p-type bulk sample. The synthetic route can be applied to obtain other low-dimensional semiconducting telluride nanostructures. PACS: 65.80.-g, 68.35.bg, 68.35.bt

  3. Green synthesis of metal sulfide nanocrystals through a general composite-surfactants-aided-solvothermal process

    Science.gov (United States)

    Zhang, Xiaoyun; An, Changhua; Wang, Shutao; Wang, Zongxian; Xia, Daohong

    2009-07-01

    In this paper, we developed a generalized and greener composite-surfactants-assisted-solvothermal process (CSSP) to produce colloidal nanoparticles of metal sulfides. X-ray diffraction (XRD), transmission electron microscopy (TEM), and X-ray photoelectron spectra (XPS) revealed that single-molecular-layer type of MoS 2 nanoparticles with diameter 6-10 nm were successfully synthesized. The molecular structure model of the capped MoS 2 nanoparticles was suggested through further examination by infrared spectra. Hexagonal CdS nanocrystals with spherical, triangle, and hollow sphere shapes were controllably synthesized by varying the experimental conditions. A possible in-situ reduction-sulfidation mechanism was proposed for the formation of Ag 2S nanocrystals, where the metal ions were reduced to metallic nanoparticles before the generation of sulfides. The obtained nanocrystals through this CSSP approach could provide the building blocks for the bottom-up approach to nanoscale fabrication in nanoscience and nanotechnology.

  4. Solvothermal synthesis of gallium-doped zinc oxide nanoparticles with tunable infrared absorption

    Science.gov (United States)

    Zhou, Haifeng; Wang, Hua; Tian, Xingyou; Zheng, Kang; Xu, Fei; Su, Zheng; Tian, Konghu; li, Qiulong; Fang, Fei

    2014-12-01

    The doping of ZnO nanoparticles (NPs) has been attracting a lot of attention both for fundamental studies and potential applications. In this manuscript, we report the preparation of gallium doped zinc oxide (GZO) NPs through the solvothermal method. In order to obtain the effective Ga doping in the ZnO crystalline lattice, we identified the optimal reaction conditions in terms of different Zn precursors, temperature, and heating rate. The results show that GZO NPs with tunable infrared absorption can be received using different molar ratios of Ga(NO3)3 and zinc stearate (Zn[CH3(CH2)16COO]2, ZnSt2) kept in the sealed autoclaves at 160 °C for 8 h. Furthermore, the growth of the GZO NPs was investigated by monitoring the optical absorption spectral and the corresponding chemical composition of aliquots extracted at different reaction time intervals.

  5. Solvothermal synthesis of vanadium phosphates in the form of xerogels, aerogels and mesostructures

    Energy Technology Data Exchange (ETDEWEB)

    Sydorchuk, V.; Zazhigalov, V. [Institute of Sorption and Endoecology, National Academy of Sciences of Ukraine, 13 General Naumov Str., Kyiv 03164 (Ukraine); Khalameida, S., E-mail: svkhal@ukr.net [Institute of Sorption and Endoecology, National Academy of Sciences of Ukraine, 13 General Naumov Str., Kyiv 03164 (Ukraine); Diyuk, E. [Institute of Sorption and Endoecology, National Academy of Sciences of Ukraine, 13 General Naumov Str., Kyiv 03164 (Ukraine); Skubiszewska-Zieba, J.; Leboda, R. [Faculty of Chemistry, Maria Curie-Sklodowska University, Maria Curie-Sklodowska Sq. 3, 20-031 Lublin (Poland); Kuznetsova, L. [Institute of Sorption and Endoecology, National Academy of Sciences of Ukraine, 13 General Naumov Str., Kyiv 03164 (Ukraine)

    2010-09-15

    Regularities and peculiarities of physicochemical changes, first of all phase transformations, during solvothermal treatment (with conventional and microwave heating) of the vanadium pentoxide and orthophosphoric acid mixture in organic solvents in the presence of reducing agents have been studied. Hemihydrate of vanadium hydrophosphate - the precursor of vanadium pyrophosphate, the active phase for n-butane to maleic anhydride oxidation, and ion exchanger with variable physicochemical characteristics, i.e. crystal structure, specific surface area, crystallite size and acidic properties - has been synthesized in the temperature range 170-200 {sup o}C. The obtained phases were examined using XRD, DTA-TG, SEM, FTIR spectroscopy, nitrogen adsorption as well as gas chromatographic determination of acidity through organic bases adsorption. The catalytic activity of prepared samples for n-butane oxidation has been investigated.

  6. Transformation of potassium Lindquist hexaniobate to various potassium niobates: solvothermal synthesis and structural evolution mechanism.

    Science.gov (United States)

    Kong, Xingang; Hu, Dengwei; Wen, Puhong; Ishii, Tomohiko; Tanaka, Yasuhiro; Feng, Qi

    2013-06-07

    This paper introduces the formation reactions and reaction mechanisms of a series of potassium niobates from a potassium salt of the Lindquist hexaniobate [Nb6O19](8-) ion under solvothermal conditions. The structure and particle morphology of the potassium niobate product can be controlled easily with the reaction solution alkalinity using this solvothermal process. KNb3O8 with a plate-like morphology, K4Nb6O17·4.5H2O with a plate-like morphology, a new phase of K2Nb2O6·H2O with fibrous morphology, KNbO3 perovskites with cubic morphology are obtained at pH = 5.5, and in 0.3, 0.5, 1.0 mol L(-1) KOH solutions at 230 °C, respectively. The reaction conditions are much milder than those in the normal hydrothermal process. Furthermore, the K2Nb2O6·H2O fibers can be topotactically transformed into KNbO3 fibers, Nb2O5 fibers after H(+)-exchange-treatment, and LiNbO3 fibers after Li(+)-exchange-treatment by heat-treatments at 730, 560, and 520 °C, respectively. The formation reaction and structure of these potassium niobates were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), selected-area electron diffraction (SAED), energy-dispersive spectroscopy (EDS), Raman spectra and TG-DTA. The formation mechanism of this series of potassium niobates from the [Nb6O19](8-) precursor is systematically explained via the correlation between the octahedrons [NbO6] sharing forms in the precursor structure and in the product structures.

  7. Ag nanowires: large-scale synthesis via a trace-salt-assisted solvothermal process and application in transparent electrodes

    Science.gov (United States)

    Jiu, Jinting; Sugahara, Tohru; Nogi, Masaya; Suganuma, Katsuaki

    2013-04-01

    Ag nanowire (AgNW) films are receiving increasing attention as new transparent conductive films poised to replace indium tine oxide materials. However, coating of AgNW surfaces with polyvinylpyrrolidone (PVP) and other impurities during synthesis causes large contact resistance between the wires leading to low conductivities in the absence of additional treatments to fuse the overlapped AgNWs together. In the present work, we demonstrated a simple method to synthesize AgNWs by the reduction of AgNO3 using PVP as the reducing agent assisted by trace amounts of salts in ethanol. The shape and yield of the AgNWs depended significantly on the concentrations of these trace salts and on reaction temperatures. The silver nanowires were about 5-20 μm in length and showed a uniform diameter of about 70 nm. A detailed growth mechanism of the AgNWs has been proposed on the basis of the observations recorded by varying these synthesis parameters. Further, the AgNWs were used to form a transparent film, which without any additional treatments showed a sheet resistance of 10.4 Ω/sq and a transmittance of 81.9 % at 550 nm. The performance of the films was attributed to the trace amounts of residual impurities on the surface of the AgNWs and to the special V-shaped morphology of the wires prepared with the solvothermal process.

  8. Facile Solvothermal Synthesis and Gas Sensitivity of Graphene/WO3 Nanocomposites

    Science.gov (United States)

    Gui, Yanghai; Yuan, Junhua; Wang, Weiming; Zhao, Jianbo; Tian, Junfeng; Xie, Bing

    2014-01-01

    Graphene has attracted enormous attention owing to its extraordinary properties, while graphene-based nanocomposites hold promise for many applications. In this paper, we present a two-step exploitation method for preparation of graphene oxides and a facile solvothermal route for preparation of few-layer graphene nanosheets and graphene/WO3 nanocomposites in an ethanol-distilled water medium. The as-synthesized samples were characterized by using field emission scanning electron microscopy (FE-SEM), high-resolution transmission electron microscopy (HRTEM), ultraviolet-visible (UV-vis) spectroscopy, Raman spectroscopy, X-ray diffraction (XRD), thermogravimetric-differential thermal analysis (TG-DTA) and gas-sensing test. The resistivity of the thick-film gas sensors based on sandwich-like graphene/WO3 nanocomposites can be controlled by varying the amount of graphene in the composites. Graphene/WO3 nanocomposites with graphene content higher than 1% show fast response, high selectivity and fine sensitivity to NOx. PMID:28788695

  9. Solvothermal synthesis of three-dimensional CeO{sub 2} micropillows and their photocatalytic property

    Energy Technology Data Exchange (ETDEWEB)

    Arul, Narayanasamy Sabari [Department of Chemical and Biochemical Engineering, Dongguk University-Seoul, 100715, Seoul (Korea, Republic of); Department of Nanoscience and Technology, Bharathiar University, Coimbatore 641046 (India); Mangalaraj, Devanesan [Department of Nanoscience and Technology, Bharathiar University, Coimbatore 641046 (India); Han, Jeong In [Department of Chemical and Biochemical Engineering, Dongguk University-Seoul, 100715, Seoul (Korea, Republic of)

    2014-07-15

    Three-dimensional (3D) CeO{sub 2} micropillows were synthesized by using solvothermal method. The pH of the precursor solution was adjusted to 10 by adding ammonium hydroxide. The structural, morphology and compositional characteristics of CeO{sub 2} micropillows were investigated by XRD, SEM, TEM and EDAX. XRD analysis showed the formation of CeO{sub 2} micropillows. BET analysis showed high specific surface area for the synthesized CeO{sub 2} micropillows (191 m{sup 2} g{sup -1}). Optical absorption of CeO{sub 2} micropillows showed enhanced photoabsorption ability with the estimated band gap energy of 2.8 eV. The photodegradation rate of the CeO{sub 2}micropillows was found to be 87% and obeys pseudo-first-order equation. The photocatalytic results indicated that the CeO{sub 2} micropillows exhibit enhanced photocatalytic property towards azo dye acid orange 7 (AO7) under UV-Vis light illumination. (copyright 2014 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  10. Mixed-solvothermal synthesis of CdS micro/nanostructures with optical and ferromagnetic properties

    Science.gov (United States)

    Zhang, Zhufeng; Ren, Yinshuan; Han, Lu; Xie, Guoya; Zhong, Bo

    2017-08-01

    Several special CdS micro/nanostructures, including microspheres, microrods, nanorods, nanosheets and nanoparticles were successfully synthesized by a simple solvothermal method using ethylenediamine (EN), ethanolamine (EA) and ethylene glycol (EG) as pure and mixed solvents with different S and Cd sources. X-ray diffraction (XRD) measurements showed that micro/nanostructures CdS had a hexagonal wurtzite structure. Scanning electron microscopy (SEM) images showed that the morphologies of CdS consisted of microrods, microsphere and nanosheets at different preparation conditions. Transmission electron microscopy (TEM) images revealed the CdS consisted of nanoparticles and nanorods at different preparation conditions. The optical properties of the CdS were measured by optical absorption spectroscopy. A vibrating sample magnetometer (VSM) measured that the CdS nanoparticles exhibited room temperature ferromagnetism. The saturation magnetization of the CdS nanoparticles was 9.109 (10-3 emu/g). The origin of the CdS nanoparticles with ferromagnetic properties is attributed to structural defects.

  11. Solvothermal synthesis, characterization and photoluminescence studies of ZnS:Eu nanocrystals

    Science.gov (United States)

    Ashwini, K.; Yashaswini; Pandurangappa, C.

    2014-11-01

    Europium doped zinc sulfide nanocrystals (ZnS:Eu) are prepared by solvothermal method. Crystallite size and lattice constant of the prepared samples are calculated from the X-ray diffraction patterns. The as-prepared samples are found to be a mixture of complex chemical groups. Heat treatment of the samples at 300 °C resulted in ZnS:Eu state. The crystal structure is not affected by the increase in the concentration of Eu from 1 mol% to 5 mol%. Fourier Transform Infrared Spectroscopy (FTIR) studies showed that characteristic absorption bands of hydroxyl groups and the acetate bands increased with increase in Eu concentration. The morphological results studied using Scanning Electron Microscopy (SEM) indicate agglomeration of nanoparticles and a marginal increase in the particle size. Photoluminescence (PL) spectra of the samples showed a prominent emission band peaked at ∼400 nm besides three weak ones at ∼422, 485 and 530 nm. The PL intensity increased with increase in Eu concentration.

  12. Solvothermal synthesis of mesoporous magnetite nanoparticles for Cr(IV) ions uptake and microwave absorption

    KAUST Repository

    Shen, Peng

    2016-05-12

    Abstract: Colloidal mesoporous magnetite nanoparticles with tunable porosity were realized by a simple and scalable solvothermal route with the aid of AOT as ligands. AOT was used to induce the anisotropic crystal growth of smaller nanocrystals and restrain their tight aggregation so as to form more mesoscale pores. Morphologies and microstructures investigation by SEM and TEM revealed that the bigger nanoparticles were composed of smaller nanocrystals with an average size of 18 nm. A possible formation mechanism was proposed for the mesoporous nanoparticles. Study of nitrogen adsorption–desorption isotherm revealed that the Brunauer–Emmett–Teller (BET) specific surface area of mesoporous nanoparticles is up to 209 m2/g, resulting from the slit-shaped pores created by the aggregation of polyhedral nanocrystals. Magnetic properties study indicated that the as-prepared nanoparticles are superparamagnetic at room temperature. Optimized mesoporous magnetite nanoparticles exhibit a maximum Cr(VI) ion sorption capacity of 12.9 mmol/g, and its absorption behavior followed a Freundlich model. Microwave absorption study indicated that porous nanoparticles own higher permeability values than that of solid nanoparticles, leading to a higher dielectric loss in the frequency range of 2–18 GHz. Graphical Abstract: [Figure not available: see fulltext.] © 2016, Springer Science+Business Media Dordrecht.

  13. Towards atomistic understanding of polymorphism in the solvothermal synthesis of ZrO2 nanoparticles.

    Science.gov (United States)

    Dippel, Ann Christin; Jensen, Kirsten M Ø; Tyrsted, Christoffer; Bremholm, Martin; Bøjesen, Espen D; Saha, Dipankar; Birgisson, Steinar; Christensen, Mogens; Billinge, Simon J L; Iversen, Bo B

    2016-11-01

    Varying atomic short-range order is correlated with the ratio of the monoclinic (m) to tetragonal (t) phase in ZrO2 nanoparticle formation by solvothermal methods. Reactions from Zr oxynitrate in supercritical methanol and Zr acetate in water (hydrothermal route) were studied in situ by X-ray total scattering. Irrespective of the Zr source and solvent, the structure of the precursor in solution consists of edge-shared tetramer chains. Upon heating, the nearest-neighbor Zr-O and Zr-Zr distances shorten initially while the medium-range connectivity is broken. Depending on the reaction conditions, the disordered intermediate transforms either rapidly into m-ZrO2, or more gradually into mixed m- and t-ZrO2 with a concurrent increase of the shortest Zr-Zr distance. In the hydrothermal case, the structural similarity of the amorphous intermediate and m-ZrO2 favors the formation of almost phase-pure m-ZrO2 nanoparticles with a size of 5 nm, considerably smaller than the often-cited critical size below which the tetragonal is assumed to be favoured. Pair distribution function analysis thus unravels ZrO2 phase formation on the atomic scale and in this way provides a major step towards understanding polymorphism of ZrO2 beyond empirical approaches.

  14. Facile Solvothermal Synthesis and Gas Sensitivity of Graphene/WO3 Nanocomposites

    Directory of Open Access Journals (Sweden)

    Yanghai Gui

    2014-06-01

    Full Text Available Graphene has attracted enormous attention owing to its extraordinary properties, while graphene-based nanocomposites hold promise for many applications. In this paper, we present a two-step exploitation method for preparation of graphene oxides and a facile solvothermal route for preparation of few-layer graphene nanosheets and graphene/WO3 nanocomposites in an ethanol-distilled water medium. The as-synthesized samples were characterized by using field emission scanning electron microscopy (FE-SEM, high-resolution transmission electron microscopy (HRTEM, ultraviolet-visible (UV-vis spectroscopy, Raman spectroscopy, X-ray diffraction (XRD, thermogravimetric-differential thermal analysis (TG-DTA and gas-sensing test. The resistivity of the thick-film gas sensors based on sandwich-like graphene/WO3 nanocomposites can be controlled by varying the amount of graphene in the composites. Graphene/WO3 nanocomposites with graphene content higher than 1% show fast response, high selectivity and fine sensitivity to NOx.

  15. Solvothermal Synthesis of Zn2SnO4 Nanocrystals and Their Photocatalytic Properties

    Directory of Open Access Journals (Sweden)

    Guang Sun

    2014-01-01

    Full Text Available Crystalline Zn2SnO4 nanoparticles were successfully synthesized via a simple solvothermal route by using Zn(CH3COO2·2H2O and SnCl4·5H2O as source materials, NaOH as mineralizing agent, and water and ethanol as mixed solvents. The used amount of NaOH was found to have an important influence on the formation of Zn2SnO4. When the molar ratio of OH− : Zn2+ : Sn4+ was set in the range from 4 : 2 : 1 to 8 : 2 : 1, Zn2SnO4 nanoparticles with different shape and size were obtained. However, when the molar ratio of OH− : Zn2+ : Sn4+ was set as 10 : 2 : 1, a mixture phase of ZnO and ZnSn(OH6 instead of Zn2SnO4 was obtained. Photodegradation measurements indicated that the Zn2SnO4 nanoparticles own better photocatalytic property to depredate methyl orange than the Zn2SnO4 nanopolyhedrons. The superior photocatalytic properties of Zn2SnO4 nanoparticles may be contributed to their small crystal size and high surface area.

  16. Solvothermal synthesis, characterization and photocatalytic performance of Zn-rich ZnWO{sub 4} nanocrystals

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yunjian [Key Laboratory of Design and Assembly of Functional Nanostructures, Fujian Institute of Research on the Structure of Matter, Fuzhou, 350002 (China); College of Chemistry and Materials Science, Huaibei Normal University, Huaibei, 235000, Anhui (China); Liping, Li [Key Laboratory of Design and Assembly of Functional Nanostructures, Fujian Institute of Research on the Structure of Matter, Fuzhou, 350002 (China); Li, Guangshe, E-mail: guangshe@fjirsm.ac.cn [Key Laboratory of Design and Assembly of Functional Nanostructures, Fujian Institute of Research on the Structure of Matter, Fuzhou, 350002 (China)

    2017-01-30

    Highlights: • An efficient size-controlled preparation method was developed for ZnWO{sub 4}. • Size-induced surface disorder was prevailed in ZnWO{sub 4} nanomaterials. • The composition of surface disordered layer was different from bulk phase. • Effects of surface composition disorder on the photoluminescence and photocatalysis were discussed. - Abstract: Present work focuses on the surface composition disorder, its origin and relevance to photoluminescent and photocatalytic properties of ZnWO{sub 4} nanocrystals. ZnWO{sub 4} nanoparticles were synthesized under solvothermal conditions, in which formic acid was employed for both the nonstoichiometry and kinetic size control. Nonstoichiometry ranging from 1.05 to 1.18 was originated from the surface Zn-rich disorder layer, as reflected by an excess of cation Zn{sup 2+} in the X-ray photoelectron spectroscopy and a new Raman vibration mode at about 930 cm{sup −1} and HR-TEM images. Surface Zn-rich disorder layer has shown a great impact on the structure and properties, including lattice expansion, band-gap narrowing, luminescence enhancement, as well as photocatalytic weakening effect. The investigation on surface composition disorder of multi-component oxides is helpful to deeply understand their formation process and further to find a new functionality optimizing approach.

  17. Solvothermal Synthesis of Mn3O4 Nanoparticle/Graphene Sheet Composites and Their Supercapacitive Properties

    Directory of Open Access Journals (Sweden)

    Y. F. Liu

    2014-01-01

    Full Text Available Mn3O4 nanoparticle/graphene sheet (GM composites were synthesized via a one-pot and low-cost solvothermal process in an ethanol solution. The as-prepared materials were characterized by X-ray diffraction, field emission scanning electron microscopy, and transmission electron microscopy. Results showed that the nanosized Mn3O4 particles had tetragonal hausmannite structure and were successfully loaded on the graphene sheets. Moreover, the electrochemical performances of GM composites produced by different mass percents of Mn2+/graphite oxide (GO were evaluated by means of cyclic voltammetry and galvanostatic charge-discharge studies. The composite prepared with Mn2+/GO mass percent of 10 : 90 showed a high specific capacitance of 245 F/g at 5 mV/s in the 6 M KOH solution and better long-term stability along with 81% of its initial capacitance after 1200 cycles at 0.5 A/g.

  18. One-step solvothermal synthesis of carnation flower-like SnS2 as superior electrodes for supercapacitor applications

    Science.gov (United States)

    Mishra, Rajneesh Kumar; Baek, Geun Woo; Kim, Kyuwon; Kwon, Hyuck-In; Jin, Sung Hun

    2017-12-01

    We report the synthesis of carnation flower-like SnS2 (CF-SnS2) via a one-step solvothermal method for potential application as supercapacitor electrodes in energy storage devices. The structural and morphological properties of CF-SnS2 were characterized by X-ray diffraction, Raman analysis, and field-emission scanning and transmission electron microscopies. X-ray photoelectron spectroscopy and scanning tunneling electron microscopy with color mapping verified the distribution of Sn and S, and depicted the successful formation of SnS2. Electrochemical studies were performed to explore the supercapacitive nature of CF-SnS2. Supercapacitors with CF-SnS2 electrodes delivered excellent cyclic voltammetry performances, superior gravimetric specific capacitances, and high power densities. The evaluated specific capacitance and power density reached ∼524.5 F/g and 12.3 W/kg, respectively, at a current density of 0.08 A/g, and ∼215.9 F/g and 61.4 W/kg, respectively, at a current density of 0.38 A/g. These values are at least two times higher than those previously reported. The long-term cyclic stability was also tested to demonstrate the endurance of the CF-SnS2-based supercapacitor, with a 66% rate retention and galvanostatic charge/discharge reversibility. These electrochemical findings indicate that CF-SnS2 is a promising candidate for electrode materials in supercapacitor applications.

  19. One-pot solvothermal synthesis of Fe3O4-PEI composite and its further modification with Au nanoparticles

    Science.gov (United States)

    Wang, Yuanfeng; Xu, Feng; Zhang, Lei; Wei, Xinlin

    2013-01-01

    A one-step strategy for the facile synthesis of polyethyleneimine-functionalized Fe3O4 (Fe3O4-PEI) composite is presented in this study. We also investigated the effects of reaction time and NaAc on the composite sizes. The composite with good dispersion, wonderful crystallization, and excellent magnetism was obtained through one-pot solvothermal reaction. In the sequential presence of PEI and colloidal gold (Au) solution, plentiful Au nanoparticles with a diameter of 5 nm were assembled on the surface of Fe3O4-PEI to get Fe3O4-PEI-Au1-PEI-Au2 (Fe3O4/Au) composite. In-depth characterization of the composite formation process was performed using transmission electron microscopy, scanning electron microscope, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, X-ray diffraction, vibrating sample magnetometer, and UV-Visible spectroscopy. The Fe3O4/Au composite was obtained with an average diameter of 150 nm, and the absorption peak was red-shifted to 580 nm. The synthesized Fe3O4/Au composite, the saturation magnetization of which was 40.4 emu/g, presented good magnetic property. Moreover, the composite could easily combine with up to 890 μg antibodies per mg, and the antibodies still kept good immunocompetence after immobilization. These advantages suggest its great potential for applications in vitro, such as separation and immunoassay.

  20. Green Synthesis of Metallic Nanoparticles via Biological Entities

    Directory of Open Access Journals (Sweden)

    Monaliben Shah

    2015-10-01

    Full Text Available Nanotechnology is the creation, manipulation and use of materials at the nanometre size scale (1 to 100 nm. At this size scale there are significant differences in many material properties that are normally not seen in the same materials at larger scales. Although nanoscale materials can be produced using a variety of traditional physical and chemical processes, it is now possible to biologically synthesize materials via environment-friendly green chemistry based techniques. In recent years, the convergence between nanotechnology and biology has created the new field of nanobiotechnology that incorporates the use of biological entities such as actinomycetes algae, bacteria, fungi, viruses, yeasts, and plants in a number of biochemical and biophysical processes. The biological synthesis via nanobiotechnology processes have a significant potential to boost nanoparticles production without the use of harsh, toxic, and expensive chemicals commonly used in conventional physical and chemical processes. The aim of this review is to provide an overview of recent trends in synthesizing nanoparticles via biological entities and their potential applications.

  1. Green Synthesis of Metallic Nanoparticles via Biological Entities

    Science.gov (United States)

    Shah, Monaliben; Fawcett, Derek; Sharma, Shashi; Tripathy, Suraj Kumar; Poinern, Gérrard Eddy Jai

    2015-01-01

    Nanotechnology is the creation, manipulation and use of materials at the nanometre size scale (1 to 100 nm). At this size scale there are significant differences in many material properties that are normally not seen in the same materials at larger scales. Although nanoscale materials can be produced using a variety of traditional physical and chemical processes, it is now possible to biologically synthesize materials via environment-friendly green chemistry based techniques. In recent years, the convergence between nanotechnology and biology has created the new field of nanobiotechnology that incorporates the use of biological entities such as actinomycetes algae, bacteria, fungi, viruses, yeasts, and plants in a number of biochemical and biophysical processes. The biological synthesis via nanobiotechnology processes have a significant potential to boost nanoparticles production without the use of harsh, toxic, and expensive chemicals commonly used in conventional physical and chemical processes. The aim of this review is to provide an overview of recent trends in synthesizing nanoparticles via biological entities and their potential applications. PMID:28793638

  2. Facile solvothermal synthesis of abnormal growth of one-dimensional ZnO nanostructures by ring-opening reaction of polyvinylpyrrolidone

    Energy Technology Data Exchange (ETDEWEB)

    Xu, G., E-mail: gxu@alum.imr.ac.cn; Wang, X.L.; Liu, G.Z.

    2015-02-28

    Graphical abstract: - Highlights: • Facile solvothermal synthesis of ZnO nanostructures in super high alkaline alcoholic condition. • The exact role and chemical transformations of PVP in solvothermal synthesis of ZnO nanostructures was revealed. • Mechanism of abnormal growth of ZnO nanopyramids was proposed based on ring-opening reaction of PVP. - Abstract: Abnormal growth of one-dimensional (1-D) ZnO nanostructures (NSs) have been accomplished with the assistance of polyvinylpyrrolidone (PVP) under a super high alkaline alcoholic solvothermal condition. The products were characterized by transmission electron microscopy (TEM), thermogravimetric analysis (TGA), X-ray diffraction (XRD), Fourier transform infrared (FT-IR) and proton nuclear magnetic resonance ({sup 1}H NMR) spectroscopy. The effect of synthetic conditions, such as reaction temperature and the addition of PVP, on the morphologies of ZnO products were investigated. The results show that PVP molecules had the significant role in the transformation of morphologies of ZnO NSs ranging from nanorods, nanoparticles to pyramids, as well as flower-like assembly features. The possible growth mechanism of ZnO pyramids was proposed based on ring-opening reaction of PVP.

  3. Facile and low temperature route to synthesis of CuS nanostructure in mesoporous material by solvothermal method.

    Science.gov (United States)

    Sohrabnezhad, Sh; Zanjanchi, M A; Hosseingholizadeh, S; Rahnama, R

    2014-04-05

    The synthesis of CuS nanomaterial in MCM-41 matrix has been realized by chemical synthesis between MCM-41, copper sulfate pentahydrate and thiourea via a solvothermal method in ethylene glycol and water, separately. X-ray diffraction analysis (XRD), diffuse reflectance spectroscopy (DRS), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and fourier transform infrared (FT-IR) were used to characterize the products. At synthesized CuS/MCM-41 sample in ethylene glycol, X-ray diffraction and diffuse reflectance spectroscopy showed pure covellite phase of copper sulfide with high crystality. But prepared CuS/MCM-41 sample in water shows the covellite, chalcocite and the djurleite phase of copper sulfide nanostructures. The formation of CuS nanostructures was confirmed by FT-IR. Photocatalytic activity of CuS/MCM-41 nanocomposites was studied for degradation of Methylene Blue (MB) under visible light. The CuS/MCM-41 nanocomposite is more effective nanocatalyst than synthesized CuS/MCM-41 sample in water for degradation of methylene blue. Several parameters were examined, catalyst amount (0.1-1gL(-1)), pH (1-13) and initial concentration of MB (0.96-10ppm). The extent of degradation was estimated from the residual concentration by spectrophotometrically. The support size was obtained in the range 60-145nm by TEM. In the same way, the average size of copper sulfide in CuSMCM-41E and CuS/MCM-41W nanostructures were obtained about 10nm and 16nm, respectively. Copyright © 2013 Elsevier B.V. All rights reserved.

  4. Surfactant-controlled composition and crystal structure of manganese(II sulfide nanocrystals prepared by solvothermal synthesis

    Directory of Open Access Journals (Sweden)

    Elena Capetti

    2015-12-01

    Full Text Available We investigated how the outcome of the solvothermal synthesis of manganese(II sulfide (MnS nanocrystals (NCs is affected by the type and amount of long chain surfactant present in the reaction mixture. Prompted by a previous observation that a larger than stoichiometric amount of sulfur is required [Puglisi, A.; Mondini, S.; Cenedese, S.; Ferretti, A. M.; Santo, N.; Ponti A. Chem. Mater. 2010, 22, 2804–2813], we carried out a wide set of reactions using Mn(II carboxylates and Mn2(CO10 as precursors with varying amounts of sulfur and carboxylic acid. MnS NCs were obtained provided that the S/Mn ratio was larger than the L/Mn ratio, otherwise MnO NCs were produced. Since MnS can crystallize in three distinct phases (rock salt α-MnS, zincblende β-MnS, and wurtzite γ-MnS, we also investigated whether the surfactant affected the NC polymorphism. We found that MnS polymorphism can be controlled by appropriate selection of the surfactant. γ-MnS nanocrystals formed when a 1:2 mixture of long chain carboxylic acid and amine was used, irrespective of the presence of carboxylic acid as a free surfactant or ligand in the metal precursor. When we used a single surfactant (carboxylic acid, alcohol, thiol, amine, α-MnS nanocrystals were obtained. The peculiar role of the amine seems to be related to its basicity. The nanocrystals were characterized by TEM and electron diffraction; ATR-FTIR spectroscopy provided information about the surfactants adsorbed on the NCs.

  5. Low-temperature solvothermal approach to the synthesis of La4Ni3O8 by topotactic oxygen deintercalation.

    Science.gov (United States)

    Blakely, Colin K; Bruno, Shaun R; Poltavets, Viktor V

    2011-07-18

    A chimie douce solvothermal reduction method is proposed for topotactic oxygen deintercalation of complex metal oxides. Four different reduction techniques were employed to qualitatively identify the relative reduction activity of each including reduction with H(2) and NaH, solution-based reduction using metal hydrides at ambient pressure, and reduction under solvothermal conditions. The reduction of the Ruddlesden-Popper nickelate La(4)Ni(3)O(10) was used as a test case to prove the validity of the method. The completely reduced phase La(4)Ni(3)O(8) was produced via the solvothermal technique at 150 °C--a lower temperature than by other more conventional solid state oxygen deintercalation methods.

  6. Shape without Structure: An Intriguing Formation Mechanism in the Solvothermal Synthesis of the Phase-Change Material Sb2 Te3.

    Science.gov (United States)

    Saltzmann, Tobias; Bornhöfft, Manuel; Mayer, Joachim; Simon, Ulrich

    2015-05-26

    We introduce a novel solvothermal synthesis of individual single crystalline Sb2 Te3 micro- and nanocrystals as a model material for phase-change switching. We identified different intermediates along the reaction path to the final Sb2 Te3 hexagonal platelets (HPs) and discuss their forming mechanism. By means of nanodiffraction (ND) in a scanning transmission electron microscope we demonstrate that the intermediates follow a hexagonal shape evolution in the amorphous state. In situ nanomanipulator measurements reveal electrical phase-change switching properties of the individual Sb2 Te3 hexagonal platelets. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. 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.

  8. Solvothermal synthesis of hierarchical TiO{sub 2} nanostructures with tunable morphology and enhanced photocatalytic activity

    Energy Technology Data Exchange (ETDEWEB)

    Fan, Zhenghua [School of Physics and Materials Science, Anhui University, Hefei 230601 (China); Meng, Fanming, E-mail: mrmeng@ahu.edu.cn [School of Physics and Materials Science, Anhui University, Hefei 230601 (China); Key laboratory of Materials Modification by Laser, Ion and Electron Beams (Dalian University of Technology), Ministry of Education, Dalian 116024 (China); Zhang, Miao [School of Physics and Materials Science, Anhui University, Hefei 230601 (China); Wu, Zhenyu [College of Chemistry & Chemical Engineering, Anhui University, Hefei 230601 (China); Sun, Zhaoqi; Li, Aixia [School of Physics and Materials Science, Anhui University, Hefei 230601 (China)

    2016-01-01

    Graphical abstract: - Highlights: • Hierarchical anatase TiO{sub 2} nanostructures with enhanced photocatalytic activity are synthesized by solvothermal method. • A mechanism for enhanced photocatalytic activity of chrysanthemum-like hierarchical TiO{sub 2} nanostructures is proposed. • A possible formation mechanism is suggested to explain the transformation from rose-like to chrysanthemum-like, and to sea-urchin-like. - Abstract: This paper presents controllable growth and photocatalytic activity of TiO{sub 2} hierarchical nanostructures by solvothermal method at different temperatures. It is revealed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) that the morphology of TiO{sub 2} can be effectively controlled as rose-like, chrysanthemum-like and sea-urchin-like only changing solvothermal temperature. BET surface area analysis confirms the presence of a mesoporous network in all the nanostructures, and shows high surface area at relatively high temperature. The photocatalytic activities of the photocatalysts are evaluated by the photodegradation of RhB under UV light irradiation. The TiO{sub 2} samples exhibit high activity on the photodegradation of RhB, which is higher than that of the commercial P25. The enhancement in photocatalytic performance can be attributed to the synergetic effect of the surface area, crystallinity, band gap and crystalline size.

  9. One-pot solvothermal synthesis of ordered intermetallic Pt2In3 as stable and efficient electrocatalyst towards direct alcohol fuel cell application

    Science.gov (United States)

    Jana, Rajkumar; Peter, Sebastian C.

    2016-10-01

    Ordered intermetallic Pt2In3 nanoparticles have been synthesized by superhydride reduction of K2PtCl4 and InCl3.xH2O precursors using facile, one-pot solvothermal method. We report surfactant free solvothermal synthesis of a novel ordered Pt2In3 intermetallic nanoparticles for the first time. The structure and morphology of the catalyst has been confirmed by powder X-ray diffraction, transmission electron microscopy, field emission scanning electron microscopy, energy-dispersive spectrometry and X-ray photoelectron spectroscopy. The electrocatalytic properties of the catalysts have been investigated by cyclic voltammetry and chronoamperometry. The as prepared Pt2In3 catalyst exhibit far superior electrocatalytic activity and stability towards alcohol oxidation over commercial Pt/C. The specific activity of as synthesized catalyst was found to be ~3.2 and ~2.3 times higher than commercial Pt/C for methanol and ethanol oxidation, respectively. This improved activity and durability of the Pt2In3 nanoparticles can make the catalyst an ideal catalyst candidate for direct alcohol fuel cell.

  10. Novel microwave-assisted solvothermal synthesis of NaYF4:Yb,Er upconversion nanoparticles and their application in cancer cell imaging.

    Science.gov (United States)

    Mi, Congcong; Tian, Zhenhuang; Cao, Can; Wang, Zhijia; Mao, Chuanbin; Xu, Shukun

    2011-12-06

    This work reports the novel microwave-assisted solvothermal synthesis and structural, topographic, spectroscopic characterization of NaYF(4):Yb,Er upconversion nanoparticles (UCNPs) as well as their application in the labeling of HeLa cells. The nanoparticles were prepared in ethylene glycol, with rare earth acetates as precursor and NH(4)F and NaCl as the fluorine and sodium sources. X-ray diffraction, transmission electron microscopy, and luminescence spectroscopy were applied to characterize the nanoparticles. Experimental results showed that the microwave-assisted solvothermal method is an effective approach to create highly crystalline, strongly luminescent UCNPs at a lower temperature (160 °C) and within a significantly shortened reaction time (only 1 h) compared to the traditional methods. The effect of fluorine source on the optical properties of UCNPs was investigated by using NH(4)F, NH(4)HF(2), NaF, and 1-butyl-3-methylimidazolium tetrafluoroborate (BmimBF(4)) as different fluorine sources; NH(4)F proved to be the best one, making the luminescent intensity increase at least 2 orders of magnitude. The UCNPs with four different colors (green, yellow, orange, and cyan) were successfully obtained. After being modified with amino groups and coupled with CEA-8 antibody, the obtained nanoparticles were successfully applied in the specific fluorescent immunolabeling and imaging of HeLa cells to further verify their function as a marker in immunolabeling. © 2011 American Chemical Society

  11. Acid-free and oxone oxidant-assisted solvothermal synthesis of graphene quantum dots using various natural carbon materials as resources

    Science.gov (United States)

    Shin, Yonghun; Park, Jintaek; Hyun, Daesun; Yang, Junghee; Lee, Jae-Hyeok; Kim, Jae-Ho; Lee, Hyoyoung

    2015-03-01

    To prepare carbon-based fluorescent materials such as graphene quantum dots (GQDs), new and effective methods are needed to convert one-dimensional (1D) or two-dimensional (2D) carbon materials to 0D GQDs. Here, we report a novel acid-free and oxone oxidant-assisted solvothermal synthesis of GQDs using various natural carbon resources including graphite (G), multiwall carbon nanotubes (M), carbon fibers (CF), and charcoal (C). This acid-free method, not requiring the neutralization process of strong acids, exhibits a simple and eco-friendly purification process and also represents a recycling production process, together with mass production and high yield. Newly synthesized GQDs exhibited a strong blue photoluminescence (PL) under 365 nm UV light illumination. The PL emission peaks of all the recycled GQDs did not change.To prepare carbon-based fluorescent materials such as graphene quantum dots (GQDs), new and effective methods are needed to convert one-dimensional (1D) or two-dimensional (2D) carbon materials to 0D GQDs. Here, we report a novel acid-free and oxone oxidant-assisted solvothermal synthesis of GQDs using various natural carbon resources including graphite (G), multiwall carbon nanotubes (M), carbon fibers (CF), and charcoal (C). This acid-free method, not requiring the neutralization process of strong acids, exhibits a simple and eco-friendly purification process and also represents a recycling production process, together with mass production and high yield. Newly synthesized GQDs exhibited a strong blue photoluminescence (PL) under 365 nm UV light illumination. The PL emission peaks of all the recycled GQDs did not change. Electronic supplementary information (ESI) available. See DOI: 10.1039/c5nr00814j

  12. Solvothermal synthesis and high optical performance of three-dimensional sea-urchin-like TiO{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Yi, E-mail: zhouyihn@163.com; Wang, Yutang; Li, Mengyao; Li, Xuzhi; Yi, Qin; Deng, Pan; Wu, Hongyan

    2015-06-15

    Graphical abstract: I–V characteristics of different TiO{sub 2} microspheres based DSSCs (a) 3D sphere-like, (b) 3D flower-like, (c) 3D sea-urchin-like. - Highlights: • 3D sea-urchin-like TiO{sub 2} was synthesized by solvothermal method. • The effects of preparation parameters on the microstructure of the microspheres were investigated. • The photoelectric properties of 3D sea-urchin-like TiO{sub 2} were studied upon DSSCs. • The PCE of the 3D sea-urchin-like TiO{sub 2} was higher than that of other morphologies. - Abstract: Three-dimensional (3D) sea-urchin-like TiO{sub 2} microspheres were successfully synthesised by solvothermal method. The effects of preparation parameters including reaction temperature, concentration and mass fraction of precursor, and solvent volume on the microstructure of the microspheres were investigated. Results of scanning electron microscopy showed that the preparation parameters played a critical role in the morphology of 3D sea-urchin-like TiO{sub 2}. In addition, when the sea-urchin-like TiO{sub 2} nanostructures were used as the dye-sensitized solar cells (DSSCs) anode, the power-conversion efficiency was higher than that of other morphologies, which was due to the special 3D hierarchical nanostructure, large specific surface area, and enhanced absorption of UV–vis of the TiO{sub 2} nanostructures.

  13. Synthesis and photovoltaic performance of reduced graphene oxide–TiO{sub 2} nanoparticles composites by solvothermal method

    Energy Technology Data Exchange (ETDEWEB)

    Shu, Wei; Liu, Yueli; Peng, Zhuoyin; Chen, Keqiang; Zhang, Chao [State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070 (China); School of Materials Science and Engineering, Wuhan University of Technology, Wuhan 430070 (China); Chen, Wen, E-mail: chenw@whut.edu.cn [State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070 (China); School of Materials Science and Engineering, Wuhan University of Technology, Wuhan 430070 (China)

    2013-06-25

    Highlights: ► Graphene–TiO{sub 2} nanocrystals composites are prepared by a simple solvothermal method. ► Photoanodes films with 0.75 wt% graphene reach the best efficiency of 5.48%. ► Graphene reduces intrinsic resistance and prolongs electron transporting life-time. -- Abstract: In the present work, the reduced graphene oxide (RGO)–TiO{sub 2} nanocrystals composites are prepared by a simple solvothermal method, and then are used as the photo-anodes in dye-sensitized solar cells (DSSCs). The result shows that the decoration of the P25 nanoparticles with reduced graphene oxide will favor for the promotion of the conversion efficiency in DSSCs. The photo-anodes films of 0.75 wt% RGO–TiO{sub 2} composites reach the best conversion efficiency of 5.5%, and it’s of 31% higher than that of the pure P25 photo-anodes films, which lies in the fact that the reduced graphene oxide in the TiO{sub 2} composites may reduce the intrinsic resistance and prolong the life-time of the electron transfer in DSSCs.

  14. Controllable 5-sulfosalicylic acid assisted solvothermal synthesis of monodispersed superparamagnetic Fe3O4 nanoclusters with tunable size

    Science.gov (United States)

    Wang, Wentao; Tang, Bingtao; Wu, Suli; Gao, Zhanming; Ju, Benzhi; Teng, Xiaoxu; Zhang, Shufen

    2017-02-01

    Monodispersed Fe3O4 nanoclusters were synthesized in a one-pot solvothermal route with 5-sulfosalicylic acid (SSA) as the functional ligand in a mixed-solvent system of diethylene glycol/ethylene glycol (DEG/EG). Nucleation and aggregation growth model was responsible for the formation of secondary structure of the clusters. In the process, the size of the clusters can be effectively controlled by varying the amounts of SSA and the volume ratio of DEG/EG. The nanoclusters exhibited superparamagnetic properties with high saturation magnetization value of about 68.7 emu g-1 at room temperature. The water-soluble small-molecule SSA grafted on the surface of Fe3O4 nanocrystals rendered the superparamagnetic clusters dispersible in water, which is crucial for potential applications in biomedical fields.

  15. Solvothermal synthesis of graphene-Sb{sub 2}S{sub 3} composite and the degradation activity under visible light

    Energy Technology Data Exchange (ETDEWEB)

    Tao, Wenguang; Chang, Jiuli; Wu, Dapeng [College of Chemistry and Chemical Engineering, Henan Normal University, Henan, Xinxiang 453007 (China); Gao, Zhiyong, E-mail: zygao512@163.com [College of Chemistry and Chemical Engineering, Henan Normal University, Henan, Xinxiang 453007 (China); Duan, Xiaoli [Engineering Technology Research Center of Motive Power and Key Materials, Henan, 453007 (China); Xu, Fang [College of Chemistry and Chemical Engineering, Henan Normal University, Henan, Xinxiang 453007 (China); Engineering Technology Research Center of Motive Power and Key Materials, Henan, 453007 (China); Jiang, Kai, E-mail: jiangkai6898@126.com [College of Chemistry and Chemical Engineering, Henan Normal University, Henan, Xinxiang 453007 (China); Engineering Technology Research Center of Motive Power and Key Materials, Henan, 453007 (China)

    2013-02-15

    Graphical abstract: Display Omitted Highlights: ► Graphene-Sb{sub 2}S{sub 3} composites were synthesized through a facile solvothermal method. ► Hydroxyl radicals are the main species responsible for the photodegradation activity. ► Graphene-Sb{sub 2}S{sub 3} demonstrated dramatically improved visible light degradation activity. -- Abstract: Novel graphene-Sb{sub 2}S{sub 3} (G-Sb{sub 2}S{sub 3}) composites were synthesized via a facile solvothermal method with graphene oxide (GO), SbCl{sub 3} and thiourea as the reactants. GO played an important role in controlling the size and the distribution of the formed Sb{sub 2}S{sub 3} nanoparticles on the graphene sheets with different density. Due to the negative surface charge, smaller Sb{sub 2}S{sub 3} particles size and efficient electrons transfer from Sb{sub 2}S{sub 3} to graphene, the composites demonstrated improved photodegradation activity on rhodamine B (RhB). Among these composites, the product G-Sb{sub 2}S{sub 3} 0.1, which was synthesized with the GO concentration of 0.1 mg/mL, exhibited the highest photodegradation activity owing to the considerable density of Sb{sub 2}S{sub 3} nanoparticles onto graphene sheet free of aggregation. Hydroxyl radicals (·OH) derived from conduction band (CB) electrons of Sb{sub 2}S{sub 3} is suggested to be responsible for the photodegradation of RhB. The high visible light degradation activity and the satisfactory cycling stability made the as-prepared G-Sb{sub 2}S{sub 3} 0.1 an applicable photocatalyst.

  16. Solvothermal synthesis of Bi2O3/BiVO4 heterojunction with enhanced visible-light photocatalytic performances

    Science.gov (United States)

    Ying, Wu; Jing, Wang; Yunfang, Huang; Yuelin, Wei; Zhixian, Sun; Xuanqing, Zheng; Chengkun, Zhang; Ningling, Zhou; Leqing, Fan; Jihuai, Wu

    2016-08-01

    Novel, three-dimensional, flower-like Bi2O3/BiVO4 heterojunction photocatalysts have been prepared by the combination of homogeneous precipitation and two-step solvothermal method followed by thermal solution of NaOH etching process. The as-obtained samples were fully characterized by X-ray diffraction, scanning electron microscopy, energy dispersive X-ray analysis, Brunauer-Emmett-Teller surface area, and UV—vis diffuse-reflectance spectroscopy in detail. The crystallinity, microstructure, specific surface area, optical property and photocatalytic activity of samples greatly changed depending on solvothermal reaction time. The photocatalytic activities of samples were evaluated on the degradation of methyl orange (MO) under visible-light irradiation. The Bi2O3/BiVO4 exhibited much higher photocatalytic activities than pure BiVO4 and conventional TiO2 (P25). The result revealed that the three-dimensional heterojunction played a critical role in the separation of the electron and hole pairs and enhancement of the interfacial charge transfer efficiency, which was responsible for the enhanced photocatalytic activity. Project supported by the National Natural Science Foundation of China (Nos. 61306077, 21301060), the Fundamental Research Funds for the Central Universities (Nos. JB-ZR1109, JB-ZR1212), the National Science Foundation of Quanzhou City (No. 2014Z108), the Promotion Program for Young and Middle-aged Teachers in Science and Technology Research of Huaqiao University (No. ZQN-PY207), Discipline Innovation Team Project of Huaqiao University (No. 201320), and the Instrumental Analysis Center Huaqiao University.

  17. Diphenylthiocarbazone (dithizone)-assisted solvothermal synthesis and optical properties of one-dimensional CdS nanostructures

    Energy Technology Data Exchange (ETDEWEB)

    Zhou Jing [State Key Laboratory of Silicon Materials and Department of Materials Science and Engineering, Zhejiang University, Hangzhou 310027 (China); Zhao Gaoling, E-mail: glzhao@zju.edu.cn [State Key Laboratory of Silicon Materials and Department of Materials Science and Engineering, Zhejiang University, Hangzhou 310027 (China); Yang Jinjian; Han Gaorong [State Key Laboratory of Silicon Materials and Department of Materials Science and Engineering, Zhejiang University, Hangzhou 310027 (China)

    2011-06-09

    Graphical abstract: Display Omitted Highlights: > 1-Dimensional CdS is prepared by diphenylthiocarbazone-assisted solvothermal method. > Diphenylthiocarbazone promotes the preferential growth of CdS along [0 0 2] direction. > CdS nanowires are synthesized with an appropriate diphenylthiocarbazone amount. > CdS nanowires exhibit unique optical absorption properties due to nanometer effect. - Abstract: One-dimensional (1D) cadmium sulfide (CdS) nanostructures with various aspect ratios were successfully synthesized by a diphenylthiocarbazone (dithizone)-assisted solvothermal method. The results showed that the dithizone-assisted synthesized samples had larger aspect ratio than that prepared in the absence of dithizone, and CdS nanowires with the highest aspect ratio were obtained with an appropriate dithizone amount (0.03 g/50 ml ethylenediamine in the present system). All the 1D CdS nanostructures were in hexagonal wurtzite phase. The as-synthesized large-scale CdS nanowires were in diameters ranging from 70 to 80 nm, length up to 20 {mu}m, and aspect ratios of 250-285. Further characterization indicated that the CdS nanowires were single crystalline with a preferential growth orientation of [0 0 2], c-axis. Two optical absorption peaks were observed at about 488 nm and 502 nm for the CdS nanowire sample with high aspect ratio in the optical absorption spectroscopy, which could be attributed to the nanometer effect of nanowires. It was found that the additive dithizone was a crucial factor in controlling the morphology and optical properties of the 1D CdS nanostructures. The growth mechanism of 1D CdS nanostructure and the effects of dithizone in the present system were discussed.

  18. Solvothermal synthesis of uranium(VI) phases with aromatic carboxylate ligands: A dinuclear complex with 4-hydroxybenzoic acid and a 3D framework with terephthalic acid

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yingjie, E-mail: yzx@ansto.gov.au [Australian Nuclear Science and Technology Organisation, Locked Bag 2001, Kirrawee DC, NSW 2232 (Australia); Karatchevtseva, Inna [Australian Nuclear Science and Technology Organisation, Locked Bag 2001, Kirrawee DC, NSW 2232 (Australia); Bhadbhade, Mohan [Mark Wainwright Analytical Centre, University of New South Wales, Kensington, NSW 2052 (Australia); Tran, Toan Trong; Aharonovich, Igor [School of Physics and Advanced Materials, University of Technology Sydney, Ultimo, NSW 2007 (Australia); Fanna, Daniel J.; Shepherd, Nicholas D. [School of Science and Health, Western Sydney University, Locked Bag 1797, Penrith, NSW 2751 (Australia); Lu, Kim [Australian Nuclear Science and Technology Organisation, Locked Bag 2001, Kirrawee DC, NSW 2232 (Australia); Li, Feng [School of Science and Health, Western Sydney University, Locked Bag 1797, Penrith, NSW 2751 (Australia); Lumpkin, Gregory R. [Australian Nuclear Science and Technology Organisation, Locked Bag 2001, Kirrawee DC, NSW 2232 (Australia)

    2016-02-15

    With the coordination of dimethylformamide (DMF), two new uranium(VI) complexes with either 4-hydroxybenzoic acid (H{sub 2}phb) or terephthalic acid (H{sub 2}tph) have been synthesized under solvothermal conditions and structurally characterized. [(UO{sub 2}){sub 2}(Hphb){sub 2}(phb)(DMF)(H{sub 2}O){sub 3}]·4H{sub 2}O (1) has a dinuclear structure constructed with both pentagonal and hexagonal bipyramidal uranium polyhedra linked through a µ{sub 2}-bridging ligand via both chelating carboxylate arm and alcohol oxygen bonding, first observation of such a coordination mode of 4-hydroxybenzoate for 5 f ions. [(UO{sub 2})(tph)(DMF)] (2) has a three-dimensional (3D) framework built with pentagonal bipyramidal uranium polyhedra linked with µ{sub 4}-terephthalate ligands. The 3D channeled structure is facilitated by the unique carboxylate bonding with nearly linear C–O–U angles and the coordination of DMF molecules. The presence of phb ligands in different coordination modes, uranyl ions in diverse environments and DMF in complex 1, and tph ligand, DMF and uranyl ion in complex 2 has been confirmed by Raman spectroscopy. In addition, their thermal stability and photoluminescence properties have been investigated. - Graphical abstract: With the coordination of dimethylformamide, two new uranyl complexes with either 4-hydroxybenzoate or terephthalate have been synthesized under solvothermal conditions and structurally characterized. - Highlights: • Solvent facilitates the synthesis of two new uranium(VI) complexes. • A dinuclear complex with both penta- and hexagonal bipyramidal uranium polyhedral. • A unique µ{sub 2}-bridging mode of 4-hydroxybenzoate via alcohol oxygen for 5 f ions. • A 3D framework with uranium polyhedra and µ{sub 4}-terephthalate ligands. • Vibration modes and photoluminescence properties are reported.

  19. Solvothermal synthesis of octahedral NiFe{sub 2}O{sub 4} nanocrystals and catalytic properties for the reduction of some aromatic nitrocompounds

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Hangsong [College of Chemistry and Materials Science, Key Laboratory of Functional Molecular Solids of Ministry of Education, Anhui Laboratory of Molecule-Based Materials, Anhui Key Laboratory of Functional Molecular Solids, Anhui Normal University, 1 Beijing Eastern Road, Wuhu 241000 (China); Ni, Yonghong, E-mail: niyh@mail.ahnu.edu.cn [College of Chemistry and Materials Science, Key Laboratory of Functional Molecular Solids of Ministry of Education, Anhui Laboratory of Molecule-Based Materials, Anhui Key Laboratory of Functional Molecular Solids, Anhui Normal University, 1 Beijing Eastern Road, Wuhu 241000 (China); Xiang, Nannan [College of Chemistry and Materials Science, Key Laboratory of Functional Molecular Solids of Ministry of Education, Anhui Laboratory of Molecule-Based Materials, Anhui Key Laboratory of Functional Molecular Solids, Anhui Normal University, 1 Beijing Eastern Road, Wuhu 241000 (China); Ma, Xiang [Center of Modern Analyses, Nanjing University, Nanjing 210093 (China); Wan, Fengying [Library of Anhui Normal University, 1 Beijing Eastern Road, Wuhu 241000 (China)

    2015-05-05

    In this paper, we report the successful synthesis of octahedral NiFe{sub 2}O{sub 4} nanocrystals with room-temperature ferrimagnetism via a mixed solvothermal process at 170 °C for 15 h, using Fe(NO{sub 3}){sub 3} and NiCl{sub 2} as starting reactants. The phase and morphology of the as-prepared product is characterized by means of powder X-ray diffraction, energy dispersive spectrometry, selected area electron diffraction (SAED), (high resolution) transmission electron microscopy, and scanning electron microscopy. Experiments showed that the as-prepared octahedral NiFe{sub 2}O{sub 4} nanocrystals owned strong catalytic activity for the reduction of some aromatic nitro-compounds such as 4-nitrophenol, 2-nitroaniline, 4-nitroaniline, and 2,4-dinitrophenol. Under the presence of 9 mg NiFe{sub 2}O{sub 4} nanocrystals, the rate constants of the reductive reactions were in turn 3.16 × 10{sup −2} min{sup −1} for 4-nitrophenol, 4.28 × 10{sup −2} min{sup −1} for 2-nitroaniline, 6.79 × 10{sup −2} min{sup −1} for 4-nitroaniline, and 3.26 × 10{sup −2} min{sup −1} for 2,4-dinitrophenol. Moreover, the present catalyst could be conveniently recycled due to its magnetism. After ten cycles, its catalytic efficiency did not obviously decrease. - Highlights: • Octahedral NiFe{sub 2}O{sub 4} nanocrystals were successfully prepared by an emulsion-solvothermal route. • NiFe{sub 2}O{sub 4} nanocrystals with the room-temperature magnetism could be used as a recyclable catalyst. • NiFe{sub 2}O{sub 4} nanocrystals showed strong catalytic activity for the reduction of 4-NP in NaBH{sub 4} solution.

  20. One-step solvothermal synthesis, a worm-shaped morphology and luminescence properties of green-emitting Y2O2S:Tb3+ nanophosphors

    Science.gov (United States)

    Liu, Fan; Lian, Jingbao; Wu, Nianchu; He, Jiao; Zhang, Xue; Liu, Feng

    2018-02-01

    The worm-shaped Y2O2S:Tb3+ nanophosphors have been successfully prepared via one-step solvothermal synthesis, using ethanediamine as the main solvent and sublimed sulfur powder as the source of sulfur without adding additional structure-directing reagents. XRD, FT-IR, FESEM, PL and CIE chromaticity diagram were used to characterize the obtained products. XRD results demonstrate that all diffraction peaks of the sample can be well indexed to pure hexagonal phase of Y2O2S with optimal condition, i.e. the molar ration of S/Y3+m = 10, solvothermal temperature T = 220 °C and synthetic time t = 24 h. When t varies from 2 h to 24 h, the morphology of Y2O2S transforms from cauliflower-like structure to worm-shaped nanoparticles with the length of ∼80 nm. The formation mechanism depending on t has also been proposed. Upon 250 nm ultraviolet (UV) light excitation, the worm-shaped Y2O2S:Tb3+ nanophosphors exhibit green emissions, corresponding to the 5D4 → 7FJ (J = 6, 5, 4, 3) transitions of Tb3+ions. The quenching concentration is 7% and its corresponding lifetime is 1216 μs. The CIE chromaticity coordinates show the tuneable emission shifting from yellow green to yellowish green with increasing concentration of Tb3+ions from 1% to 7%. Those results suggest that the worm-shaped Y2O2S:Tb3+ nanophosphors may have potential applications in X-ray intensifying screens, fluorescence and biomedical fields.

  1. Simultaneous Synthesis of WO3-x Quantum Dots and Bundle-Like Nanowires Using a One-Pot Template-Free Solvothermal Strategy and Their Versatile Applications.

    Science.gov (United States)

    Wang, Yao; Wang, Xiaoxia; Xu, Yuanhong; Chen, Tao; Liu, Mengli; Niu, Fushuang; Wei, Shuang; Liu, Jingquan

    2017-04-01

    Tungsten oxide (WO3-x ), a new alternative to conventional semiconductor material, has attracted numerous attentions owning to its widespread potential applications. Various methods have been reported for the synthesis of WO3-x nanostructures such as nanowires or nanodots. However, templates or surfactants are often required for the synthesis, which significantly complicate the process and hinder the broad applications. Herein, one-pot template/surfactant-free solvothermal method is proposed to synthesize the WO3-x nanostructures including fluorescent quantum dots (QDs) and bundle-like nanowires simultaneously. The as-prepared WO3-x QDs can be well dispersed in aqueous medium, exhibit excellent photoluminescent properties, and show an average size of 3.25 ± 0.25 nm as evidenced by transmission electron microscopy. Meanwhile, the diameter of the WO3-x nanowires is found to be about 27.5 nm as manifested by the scanning electron microscope images. The generation mechanism for these two WO3-x nanostructures are systematically studied and proposed. The WO3-x QDs have been successfully applied in efficient fluorescent staining and specific ferric ion detection. Moreover, the WO3-x nanowires can be utilized as effective dielectric materials for electromagnetic wave absorption. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. One-pot solvothermal synthesis of a well-ordered layered sodium aluminoalcoholate complex: a useful precursor for the preparation of porous Al2O3 particles

    Energy Technology Data Exchange (ETDEWEB)

    Li, XS; Michaelis, VK; Ong, TC; Smith, SJ; McKay, I; Muller, P; Griffin, RG; Wang, EN

    2014-01-01

    One-pot solvothermal synthesis of a robust tetranuclear sodium hexakis(glycolato)tris(methanolato)aluminate complex Na-3[Al-4(OCH3)(3)(OCH2CH2O)(6)] via a modified yet rigorous base-catalyzed transesterification mechanism is presented here. Single crystal X-ray diffraction (SCXRD) studies indicate that this unique Al complex contains three pentacoordinate Al3+ ions, each bound to two bidentate ethylene glycolate chelators and one monodentate methanolate ligand. The remaining fourth Al3+ ion is octahedrally coordinated to one oxygen atom from each of the six surrounding glycolate chelators, effectively stitching the three pentacoordinate Al moieties together into a novel tetranuclear Al complex. This aluminate complex is periodically self-assembled into well-ordered layers normal to the [110] axis with the intra-/inter-layer bonding involving extensive ionic bonds from the three charge-counterbalancing Na+ cations rather than the more typical hydrogen bonding interactions as a result of fewer free hydroxyl groups present in its structure. It can also serve as a valuable precursor toward the facile synthesis of high-surface-area alumina powders using a very efficient rapid pyrolysis technique.

  3. Solvothermal synthesis of InP quantum dots and their enhanced luminescent efficiency by post-synthetic treatments.

    Science.gov (United States)

    Byun, Ho-June; Lee, Ju Chul; Yang, Heesun

    2011-03-01

    InP quantum dots (QDs) were solvothermally synthesized by using a greener phosphorus source of P(N(CH(3))(2))(3) instead of highly toxic P(TMS)(3) widely used, and subsequently subjected to a size-sorting processing. While as-grown QDs showed an undetectably low emission intensity, post-synthetic treatments such as photo-etching, photo-radiation, and photo-assisted ZnS shell coating gave rise to a substantial increase in emission efficiency due to the effective removal and passivation of surface states. The emission efficiency of the photo-etched QDs was further enhanced by a consecutive UV photo-radiation, attributable to the photo-oxidation at QD surface. Furthermore, a relatively thick ZnS shell on the surface of InP QDs that were surface-modified with hydrophilic ligands beforehand was photochemically generated in an aqueous solution at room temperature. The resulting InP/ZnS core/shell QDs, emitting from blue to red wavelengths, were more efficient than the above photo-treated InP QDs, and their luminescent properties (emission bandwidth and quantum yield) were comparable to those of InP QDs synthesized with P(TMS)(3). Structural, size, and compositional analyses on InP/ZnS QDs were also conducted to elucidate their core/shell structure. Copyright © 2010 Elsevier Inc. All rights reserved.

  4. Synthesis of Cu-Poor Copper-Indium-Gallium-Diselenide Nanoparticles by Solvothermal Route for Solar Cell Applications

    Directory of Open Access Journals (Sweden)

    Chung Ping Liu

    2014-01-01

    Full Text Available Copper-indium-gallium-diselenide (CIGS thin films were fabricated using precursor nanoparticle ink and sintering technology. The precursor was a Cu-poor quaternary compound with constituent ratios of Cu/(In+Ga=0.603, Ga/(In+Ga=0.674, and Se/(Cu+In+Ga=1.036. Cu-poor CIGS nanoparticles of chalcopyrite for solar cells were successfully synthesized using a relatively simple and convenient elemental solvothermal route. After a fixed reaction time of 36 h at 180°C, CIGS nanocrystals with diameters in the range of 20–70 nm were observed. The nanoparticle ink was fabricated by mixing CIGS nanoparticles, a solvent, and an organic polymer. Analytical results reveal that the Cu-poor CIGS absorption layer prepared from a nanoparticle-ink polymer by sintering has a chalcopyrite structure and a favorable composition. For this kind of sample, its mole ratio of Cu : In : Ga : Se is equal to 0.617 : 0.410 : 0.510 : 2.464 and related ratios of Ga/(In+Ga and Cu/(In+Ga are 0.554 and 0.671, respectively. Under the condition of standard air mass 1.5 global illumination, the conversion efficiency of the solar cell fabricated by this kind of sample is 4.05%.

  5. Photocatalytic degradation of methyl orange over nitrogen-fluorine codoped TiO2 nanobelts prepared by solvothermal synthesis.

    Science.gov (United States)

    He, Zuoli; Que, Wenxiu; Chen, Jing; Yin, Xingtian; He, Yucheng; Ren, Jiangbo

    2012-12-01

    Anatase type nitrogen-fluorine (N-F) codoped TiO(2) nanobelts were prepared by a solvothermal method in which amorphous titania microspheres were used as the precursors. The as-prepared TiO(2) nanobelts are composed of thin narrow nanobelts and it is noted that there are large amount of wormhole-like mesopores on these narrow nanobelts. Photocatalytic activity of the N-F codoped TiO(2) nanobelts was measured by the reaction of photocatalytic degradation of methyl orange. Results indicate that the photocatalytic activity of the N-F codoped TiO(2) nanobelts is higher than that of P25, which is mainly ascribed to wormhole-like mesopores like prison, larger surface area, and enhanced absorption of light due to N-F codoping. Interestingly, it is also found that the photocatalytic activity can be further enhanced when tested in a new testing method because more photons can be captured by the nanobelts to stimulate the formation of the hole-electron pair.

  6. Solvothermal synthesis of Zn1−xMnxO nanoparticles using oxalate precursor route: Optical and magnetic properties

    Directory of Open Access Journals (Sweden)

    Tokeer Ahmad

    2017-05-01

    Full Text Available Nanoparticles of Zn1−xMnxO (x = 0.022, 0.061 and 0.098 were synthesized by a modified solvothermal method through the oxalate precursor route. The precursors were characterized by TG/DTA analysis. Their kinetics has also been studied using the Freeman and Carroll method. The prepared oxide nanoparticles were investigated by powder X-ray diffraction (PXRD, transmission electron microscopy (TEM, optical and BET surface area studies. PXRD patterns were matched with hexagonal ZnO structure, however few impurity peaks of ZnMnO3 appeared. Reflectance measurements showed that Mn2+ is incorporated in the Zn matrix. The band gap decreases on increasing Mn concentration. The particle size decreases from 18 to 9 nm and the surface area increases (255.4–582.9 m2g−1 on increasing Mn concentration. All these solid solutions show paramagnetic behaviour with very weak antiferromagnetic interactions. The effective magnetic moment of these nanoparticles comes out to be 4.91, 4.77 and 4.18 μB/Mn2+.

  7. Solvothermal synthesis of TiO2 nanocrystals with {001} facets using titanic acid nanobelts for superior photocatalytic activity

    Science.gov (United States)

    Cao, Yuhui; Zong, Lanlan; Li, Qiuye; Li, Chen; Li, Junli; Yang, Jianjun

    2017-01-01

    Anatase TiO2 nanocrystals exposed with {001} facets were fabricated by solvothermal strategy in HF-C4H9OH mixed solution, using titanic acid nanobelts (TAN) as a precursor. The shape of TAN is a long flat plane with a high aspect ratio, and F- is easily adsorbed on the surface of the nanobelts, inducing a higher exposure of {001} facet of TiO2 nanoparticles during the structure reorganization. The exposed percentage of {001} facets could vary from 40 to 77% by adjusting the amount of HF. The as-prepared samples were characterized by transmission electron microscopy, N2 adsorption-desorption isotherms, X-ray diffraction, Raman spectroscopy, and X-ray photoelectron spectroscope. The photocatalytic measurement showed that TiO2 nanocrystals with 77% {001} facets exhibited much superior photocatalytic activity for photodegradation of methyl orange, methylene blue, and rhodamine B. And what's more, the mineralization rate of methyl orange was as high as 96% within 60 min. The photocatalytic enhancement is due to a large amount of the high energetic {001} facets exposing, the special truncated octahedral morphology and a stronger ability for dyes adsorption.

  8. Solvothermal synthesis and photoluminescence properties of ZnS:Mn2+/ZnO core-shell nanocrystals.

    Science.gov (United States)

    Wang, Yuhua; Li, Chengyan; Peng, Lingling

    2010-03-01

    High-quality ZnS:Mn2+ and ZnS:Mn2+/ZnO core-shell nanocrystals (NCs) were synthesized via a solvothermal method, and characterized by X-ray diffraction (XRD), Transmission electron microscopy (TEM), ultraviolet-visible (UV-vis) and photoluminescence (PL) spectra. Compared with the bare ZnS:Mn2+ NCs (10 nm), the obtained ZnS:Mn2+/ZnO core-shell NCs have a smaller size (4 nm) and better dispersion, which could be attributed to the added ammonia that adsorbed on the surface of ZnS nuclei and hindered their further growth. From the PL spectrum of ZnS:Mn2+NCs, orange luminescence at about 595 nm is observed, which is attributed to the 4T1-6A1 transition of the Mn2+. Meanwhile, the PL intensity of the ZnS:Mn2+/ZnO core-shell NCs is enhanced, and the emission peak is shifted from 595 to 581 nm. The enhancement of the PL intensity is due to the elimination of the surface defects after the growth of the ZnO shell on ZnS:Mn2+ NCs, while the peak blue shift is mainly ascribed to the stress from the mismatch of lattice constants between ZnS and ZnO NCs.

  9. Solvothermal synthesis of TiO{sub 2} nanocrystals with {001} facets using titanic acid nanobelts for superior photocatalytic activity

    Energy Technology Data Exchange (ETDEWEB)

    Cao, Yuhui; Zong, Lanlan [National & Local Joint Engineering Research Center for Applied Technology of Hybrid Nanomaterials, Henan University, Kaifeng, 475004 (China); Li, Qiuye, E-mail: qiuyeli@henu.edu.cn [National & Local Joint Engineering Research Center for Applied Technology of Hybrid Nanomaterials, Henan University, Kaifeng, 475004 (China); Collaborative Innovation Center of Nano Functional Materials and Applications of Henan Province, Henan University, Kaifeng, 475004 (China); Li, Chen; Li, Junli [National & Local Joint Engineering Research Center for Applied Technology of Hybrid Nanomaterials, Henan University, Kaifeng, 475004 (China); Yang, Jianjun, E-mail: yangjianjun@henu.edu.cn [National & Local Joint Engineering Research Center for Applied Technology of Hybrid Nanomaterials, Henan University, Kaifeng, 475004 (China); Collaborative Innovation Center of Nano Functional Materials and Applications of Henan Province, Henan University, Kaifeng, 475004 (China)

    2017-01-01

    Highlights: • TiO{sub 2} exposed with {001} facets were firstly prepared using TAN as Ti source. • The mineralization rate of MO on sample with 77% {001} facets was as high as 96%. • The superior photocatalytic activity was greatly due to {001} facets exposing. - Abstract: Anatase TiO{sub 2} nanocrystals exposed with {001} facets were fabricated by solvothermal strategy in HF-C{sub 4}H{sub 9}OH mixed solution, using titanic acid nanobelts (TAN) as a precursor. The shape of TAN is a long flat plane with a high aspect ratio, and F{sup −} is easily adsorbed on the surface of the nanobelts, inducing a higher exposure of {001} facet of TiO{sub 2} nanoparticles during the structure reorganization. The exposed percentage of {001} facets could vary from 40 to 77% by adjusting the amount of HF. The as-prepared samples were characterized by transmission electron microscopy, N{sub 2} adsorption-desorption isotherms, X-ray diffraction, Raman spectroscopy, and X-ray photoelectron spectroscope. The photocatalytic measurement showed that TiO{sub 2} nanocrystals with 77% {001} facets exhibited much superior photocatalytic activity for photodegradation of methyl orange, methylene blue, and rhodamine B. And what’s more, the mineralization rate of methyl orange was as high as 96% within 60 min. The photocatalytic enhancement is due to a large amount of the high energetic {001} facets exposing, the special truncated octahedral morphology and a stronger ability for dyes adsorption.

  10. Phase- and morphology-controlled synthesis of CdSe microstructures through an effective mixed-solvothermal route

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Hanmei, E-mail: hmhu@ustc.edu [Key Laboratory of Functional Molecule Design and Interface Process, Anhui Jianzhu University, Hefei 230601 (China); School of Materials and Chemical Engineering, Anhui Jianzhu University, Hefei 230601 (China); Zheng, Qiang [Key Laboratory of Functional Molecule Design and Interface Process, Anhui Jianzhu University, Hefei 230601 (China); Deng, Chonghai, E-mail: chdeng@mail.ustc.edu.cn [Department of Chemical and Materials Engineering, Hefei University, Hefei 230601 (China); Sun, Mei; Zhang, Kehua; Tang, Laihua [Key Laboratory of Functional Molecule Design and Interface Process, Anhui Jianzhu University, Hefei 230601 (China)

    2015-03-15

    Cubic-phase CdSe (C–CdSe) hollow microspheres and hexagonal-phase CdSe (H–CdSe) urchin-like microstructures have been controllably synthesized through an effective mixed solvothermal method in the absence of any surfactants. The products were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), UV–Vis absorption spectroscopy and photoluminescence spectroscopy. The volume ratio of ethylenediamine and ethanol of two solvents is a key factor that determines the phase and shape of CdSe crystals. When the volume ratio of ethylenediamine and ethanol is changed from 1:3, through 1:1 to 4:1, CdSe crystals can be changed from hollow spheres (cubic phase), through acanthosphere (mixed phase) to urchin-like architectures (hexagonal phase). Based on the investigation of the influence of solvent ratio on the phase and morphology of CdSe, an “in situ phase transformation and crystal growth” mechanism is proposed. Optical properties indicate that the as-obtained H–CdSe urchin-like microstructures have much stronger optical absorption and emission than C–CdSe hollow microspheres. - Highlights: • Cubic-phase CdSe hollow microspheres and hexagonal-phase CdSe urchin-like microstructures were controllably prepared. • The influence of solvent ratio on the phase and morphology of CdSe was investigated. • The optical properties of the obtained CdSe crystals were investigated. • An “in situ phase transformation and crystal growth” mechanism was proposed.

  11. Light-Assisted Solvothermal Chemistry Using Plasmonic Nanoparticles

    OpenAIRE

    Robert, H.; Kundrat, F.; Bermudez-Urena, E.; Rigneault, H.; Monneret, S.; Quidant, R.; Polleux, J.; Baffou, G.

    2016-01-01

    Solvothermal synthesis, denoting chemical reactions occurring in metastable liquids above their boiling point, normally requires the use of a sealed autoclave under pressure to prevent the solvent from boiling. This work introduces an experimental approach that enables solvothermal synthesis at ambient pressure in an open reaction medium. The approach is based on the use of gold nanoparticles deposited on a glass substrate and acting as photothermal sources. To illustrate the approach, the se...

  12. One-step solvothermal synthesis of TiO2-reduced graphene oxide nanocomposites with enhanced visible light photoreduction of Cr(VI)

    Science.gov (United States)

    Shaikh, Aasiya; Mishra, Shailendra Prasad; Mohapatra, Priyabrata; Parida, Smrutiranjan

    2017-06-01

    Hexavalent chromium, Cr(VI), is a mutagenic and carcinogenic heavy metal environmental pollutant. Photoreduction is one of the remediation methods of the hexavalent chromium Cr(VI), which necessitates design of an efficient catalyst for visible light performance. Here, we report a one-step solvothermal synthesis of TiO2-reduced graphene oxide (TiO2- xRGO) composite catalysts using a mild reducing agent, dimethylformamide (DMF). Nanoscale TiO2 particles in the size range of 4-9 nm were formed on the reduced graphene sheets. The formation of the composite catalysts was accompanied by the appearance of a large fluorescence quenching, which indicates an efficient separation of photogenerated electrons and holes. The composites displayed excellent photoreduction of Cr(VI) in the visible light, which was found to be a function of the weight percentage of RGO in the composite. At the optimum composition of TiO2- xRGO, a maximum removal rate of 96% was recorded, which was higher than that of the pristine TiO2, which showed no appreciable catalytic activity under the same condition. The performance degraded with increasing RGO content in the composite, which can be attributed to the higher electron-hole recombination on the RGO surface. The Cr(VI) photoreduction also exhibited a pH dependence. The highest removal rate was observed in the acidic medium.

  13. Effect of Water Content in Ethylene Glycol Solvent on the Size of ZnO Nanoparticles Prepared Using Microwave Solvothermal Synthesis

    Directory of Open Access Journals (Sweden)

    Jacek Wojnarowicz

    2016-01-01

    Full Text Available Zinc oxide nanoparticles (ZnO NPs were obtained by the microwave solvothermal synthesis (MSS method. The precursor of the MSS reaction was a solution of hydrated zinc acetate in ethylene glycol with water addition. It was proved that by controlling the water concentration in the precursor it was possible to control the size of ZnO NPs in a programmed manner. The less the water content in the precursor, the smaller the size of ZnO NPs obtained. The obtained NPs with the average particle size ranging from 25 nm to 50 nm were characterised by homogeneous morphology and a narrow distribution of particle sizes. The following parameters of the obtained ZnO NPs were determined: pycnometric density, specific surface area, phase purity, chemical composition, lattice parameters, average particle size, and particle size distribution. The average size of ZnO NPs was determined using Scherrer’s formula, Nanopowder XRD Processor Demo web application, by converting the results of the specific surface area, and TEM tests using the dark field technique. ZnO morphology and structure were determined using scanning electron microscopy (SEM and transmission electron microscopy (TEM. The test performed by the X-ray powder diffraction (XRD confirmed that crystalline ZnO, pure in terms of phase, had been obtained.

  14. Fast microwave-assisted solvothermal synthesis of metal nanoparticles (Pd, Ni, Sn) supported on sulfonated MWCNTs: Pd-based bimetallic catalysts for ethanol oxidation in alkaline medium

    CSIR Research Space (South Africa)

    Ramulifho, T

    2012-01-01

    Full Text Available The preparation of metal nanoparticles (Pd, Ni, Sn) supported on sulfonated multi-walled carbon nanotubes (SF-MWCNTs) using a very rapid microwave-assisted solvothermal strategy has been described. Electrocatalytic behaviour of the SF...

  15. One-Pot Solvothermal Synthesis of Highly Emissive, Sodium-Codoped, LaF3 and BaLaF5 Core-Shell Upconverting Nanocrystals

    Directory of Open Access Journals (Sweden)

    Joshua T. Stecher

    2014-01-01

    Full Text Available We report a one-pot solvothermal synthesis of sub-10 nm, dominant ultraviolet (UV emissive upconverting nanocrystals (UCNCs, based on sodium-codoped LaF3 and BaLaF5 (0.5%Tm; 20%Yb and their corresponding core@shell derivatives. Elemental analysis shows a Na-codopant in these crystal systems of ~20% the total cation content; X-ray diffraction (XRD data indicate a shift in unit cell dimensions consistent with these small codopant ions. Similarly, X-ray photoelectron spectroscopic (XPS analysis reveals primarily substitution of Na+ for La3+ ions (97% of total Na+ codopant in the crystal system, and interstitial Na+ (3% of detected Na+ and La3+ (3% of detected La3+ present in (NaLaF3 and only direct substitution of Na+ for Ba2+ in Ba(NaLaF5. In each case, XPS analysis of La 3d lines show a decrease in binding energy (0.08–0.25 eV indicating a reduction in local crystal field symmetry surrounding rare earth (R.E.3+ ions, permitting otherwise disallowed R.E. UC transitions to be enhanced. Studies that examine the impact of laser excitation power upon luminescence intensity were conducted over 2.5–100 W/cm2 range to elucidate UC mechanisms that populate dominant UV emitting states. Low power saturation of Tm3+ 3F3 and 3H4 states was observed and noted as a key initial condition for effective population of the 1D2 and 1I6 UV emitting states, via Tm-Tm cross-relaxation.

  16. Particle size-controllable microwave-assisted solvothermal synthesis of the high-voltage cathode material LiCoPO4 using water/ethylene glycol solvent blends

    Science.gov (United States)

    Ludwig, Jennifer; Haering, Dominik; Doeff, Marca M.; Nilges, Tom

    2017-03-01

    Particle size-tuned platelets of the high-voltage cathode material LiCoPO4 for Li-ion batteries have been synthesized by a simple one-step microwave-assisted solvothermal process using an array of water/ethylene glycol (EG) solvent mixtures. Particle size control was achieved by altering the concentration of the EG co-solvent in the mixture between 0 and 100 vol%, with amounts of 0-80 vol% EG producing single phase, olivine-type LiCoPO4. The particle sizes of the olivine materials were significantly reduced from about 1.2 μm × 1.2 μm × 500 nm (0 vol% EG) to 200 nm × 100 nm × 50 nm (80 vol% EG) with increasing EG content, while specific surface areas increased from 2 to 13 m2 g-1. The particle size reduction could mainly be attributed to the modified viscosities of the solvent blends. Owing to the soft template effect of EG, the crystals exhibited the smallest dimensions along the [010] direction of the Li diffusion pathways in the olivine crystal structure, resulting in enhanced lithium diffusion properties. The relationship between the synthesis, crystal properties and electrochemical performance was further elucidated, indicating that the electrochemical performances of the as-prepared materials mainly depend on the solvent composition and the respective particle size range. LiCoPO4 products obtained from reaction media with low and high EG contents exhibited good electrochemical performances (initial discharge capacities of 87-124 mAh g-1 at 0.1 C), whereas materials made from medium EG concentrations (40-60 vol% EG) showed the highest capacities and gravimetric energy densities (up to 137 mAh g-1 and 658 Wh kg-1 at 0.1 C), excellent rate capabilities, and cycle life.

  17. One-pot solvothermal synthesis of Fe{sub 3}O{sub 4}-PEI composite and its further modification with Au nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Wang Yuanfeng, E-mail: foodlab2010@gmail.com; Xu Feng; Zhang Lei; Wei, Xinlin, E-mail: foodlab2010@yahoo.com.cn [Shanghai Normal University, Institute of Food Engineering, College of Life and Environment Science (China)

    2013-01-15

    A one-step strategy for the facile synthesis of polyethyleneimine-functionalized Fe{sub 3}O{sub 4} (Fe{sub 3}O{sub 4}-PEI) composite is presented in this study. We also investigated the effects of reaction time and NaAc on the composite sizes. The composite with good dispersion, wonderful crystallization, and excellent magnetism was obtained through one-pot solvothermal reaction. In the sequential presence of PEI and colloidal gold (Au) solution, plentiful Au nanoparticles with a diameter of 5 nm were assembled on the surface of Fe{sub 3}O{sub 4}-PEI to get Fe{sub 3}O{sub 4}-PEI-Au{sub 1}-PEI-Au{sub 2} (Fe{sub 3}O{sub 4}/Au) composite. In-depth characterization of the composite formation process was performed using transmission electron microscopy, scanning electron microscope, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, X-ray diffraction, vibrating sample magnetometer, and UV-Visible spectroscopy. The Fe{sub 3}O{sub 4}/Au composite was obtained with an average diameter of 150 nm, and the absorption peak was red-shifted to 580 nm. The synthesized Fe{sub 3}O{sub 4}/Au composite, the saturation magnetization of which was 40.4 emu/g, presented good magnetic property. Moreover, the composite could easily combine with up to 890 {mu}g antibodies per mg, and the antibodies still kept good immunocompetence after immobilization. These advantages suggest its great potential for applications in vitro, such as separation and immunoassay.

  18. Microwave-assisted solvothermal synthesis of flower-like Ag/AgBr/BiOBr microspheres and their high efficient photocatalytic degradation for p-nitrophenol

    Energy Technology Data Exchange (ETDEWEB)

    Li, Tingting, E-mail: tingtingli1983@hotmail.com [Department of Chemistry and Chemical Engineering, Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Changsha 410082 (China); State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan University, Changsha 410082 (China); Department of Environment and Chemical Engineering, Key Laboratory of Jiangxi Province for Ecological Diagnosis, Remediation and Pollution Control, Nanchang Hangkong University, Nanchang 330063 (China); Luo, Shenglian, E-mail: sllou@hnu.edu.cn [Department of Chemistry and Chemical Engineering, Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Changsha 410082 (China); State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan University, Changsha 410082 (China); Department of Environment and Chemical Engineering, Key Laboratory of Jiangxi Province for Ecological Diagnosis, Remediation and Pollution Control, Nanchang Hangkong University, Nanchang 330063 (China); Yang, Lixia [Department of Environment and Chemical Engineering, Key Laboratory of Jiangxi Province for Ecological Diagnosis, Remediation and Pollution Control, Nanchang Hangkong University, Nanchang 330063 (China)

    2013-10-15

    Flower-like Ag/AgBr/BiOBr microspheres were successfully fabricated by the approach of microwave-assisted solvothermal and in situ photo-assisted reduction. A reactive ionic liquid 1-hexadecyl-3-methylimidazolium bromide ([C{sub 16}mim]Br) was employed as Br source in the presence of surfactant polyvinylpyrrolidone (PVP). The photocatalytic activity of Ag/AgBr/BiOBr towards the decomposition of p-nitrophenol under visible light irradiation was evaluated. The results indicated that Ag/AgBr/BiOBr showed enhanced photocatalytic activity towards p-nitrophenol, comparing with P25, BiOBr and Ag/AgBr. More than 96% of p-nitrophenol was decomposed in 3.5 h under visible-light irradation. The excellent photocatalytic activity of flower-like Ag/AgBr/BiOBr microspheres can be attributed to the large specific surface area, strong visible-light absorption, suitable energy band structure and surface plasmon resonance effect of Ag nanoparticles. The possible photocatalytic mechanism was proposed based on the active species test and band gap structure analysis. - Graphical abstract: The photocatalytic reaction mechanisms of the as-prepared Ag/AgBr/BiOBr. Display Omitted - Highlights: • Successful synthesis of flower-like Ag/AgBr/BiOBr microspheres. • The Ag/AgBr/BiOBr showed much higher photocatalytic activity towards p-nitrophenol as compared to BiOBr and Ag/AgBr. • The reasons for the excellent photocatalytic activity are the large specific surface area, strong visible-light absorption and surface plasmon resonance effect of Ag nanoparticles. • The O{sub 2}·{sup −}, Br{sup 0} and photogenerated h{sup +} play key roles in the photocatalytic degradation process.

  19. Phase-controlled synthesis of Cu{sub 2}ZnSnS{sub 4} powders via the microwave-assisted solvothermal route

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Yi-Hsung; Das, Subrata; Yang, Che-Yuan; Sung, Jen-Cheng; Lu, Chung-Hsin, E-mail: chlu@ntu.edu.tw

    2015-05-25

    Highlights: • Cu{sub 2}ZnSnS{sub 4} powders were prepared via the microwave-assisted solvothermal route. • Kesterite and wurtzite phase were formed via adjusting the amount of ethylenediamine. • Cu{sub 2}S was reacted with constituent ions and hydrogen sulfide ions to form Cu{sub 2}ZnSnS{sub 4}. • Single-phased kesterite and wurtzite Cu{sub 2}ZnSnS{sub 4} powders were derived in this study. - Abstract: Cu{sub 2}ZnSnS{sub 4} was successfully prepared via the microwave-assisted solvothermal route at the reaction temperature as low as 180 °C. In comparison with the conventional solution process for preparing Cu{sub 2}ZnSnS{sub 4} powders, the reaction time was significantly reduced to 1 h, and the preparation procedures were simplified with the incorporation of microwave irradiation technique. The mobility of ions and dipoles are suggested to have been accelerated via the microwave, thereby enhancing the reaction rates. Kesterite and wurtzite Cu{sub 2}ZnSnS{sub 4} powders were formed via adjusting the volume fraction of ethylenediamine in the microwave-solvothermal process. The amount of ethylenediamine affected the morphology of the derived powders due to the selective passivation of ethylenediamine on Cu{sub 2}ZnSnS{sub 4}. The microscopic analysis revealed that the samples prepared with high ethylenediamine concentrations had large particle sizes. The enhanced grain size reduced the surface recombination and increased the photoluminescence intensity of Cu{sub 2}ZnSnS{sub 4} particles. During the microwave-assisted solvothermal process, Cu{sub 2}S was formed first and reacted with the constituent ions and hydrogen sulfide ions to form Cu{sub 2}ZnSnS{sub 4} powders.

  20. Synthesis and characterization of K(Ta(x)Nb(1_x))O3 particles by high temperature mixing method under hydrothermal and solvothermal conditions.

    Science.gov (United States)

    Gu, Honghui; Zhu, Kongjun; Qiu, Jinhao; Ji, Hongli; Cao, Yang; Jin, Jiamei

    2013-02-01

    KTa(x)Nb(1_x)O3 (KTN) particles with an orthorhombic perovskite structure were synthesized via a high temperature mixing method (HTMM) under hydrothermal and solvothermal conditions. The obtained products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), transmission electron microscopy (TEM), selected area electron diffraction (SAED), and high-resolution transmission electron microcopy (HRTEM). The influences of alkaline concentration and Ta doping amounts on the phase structure and morphology of the obtained powders were investigated. The results showed that KTN powders could be solvothermally prepared when the KOH concentration is as low as 0.5 M. In comparison with the hydrothermal process, supercritical isopropanol plays an important role in synthesizing KTN particles under milder conditions. The KTa(0.4)Nb(0.6)O3 particles solvothermally synthesized in isopropanol are made of well crystallized and single crystalline particles with a size of about 100-200 nm. Room temperature PL studies excited at different wavelengths reveal five emission bands centered at about 421 nm, 446 nm, 468 nm, 488 nm, and 498 nm, respectively. The supercritical process proposed here provides a new potential route for synthesizing other perovskite-type materials.

  1. A facile one-step solvothermal synthesis of graphene/rod-shaped TiO2 nanocomposite and its improved photocatalytic activity

    Science.gov (United States)

    Dong, Pengyu; Wang, Yuhua; Guo, Linna; Liu, Bin; Xin, Shuangyu; Zhang, Jia; Shi, Yurong; Zeng, Wei; Yin, Shu

    2012-07-01

    Graphene sheets were obtained through solvothermal reduction of colloidal dispersion of graphene oxide in benzyl alcohol. The graphene/rod-shaped TiO2 nanocomposite was synthesized by this novel and facile solvothermal method. During the solvothermal reaction, both the reduction of graphene oxide and the growth of rod-shaped TiO2 nanocrystals as well as its deposition on graphene occur simultaneously. The photocatalytic activity of graphene/rod-shaped TiO2 and graphene/spherical TiO2 nanocomposites was compared. In the photocatalytic degradation of methyl orange (MO), the graphene/rod-shaped TiO2 nanocomposite with the optimized graphene content of 0.48 wt% shows good stability and exhibits a significant enhancement of photocatalytic activity compared to the bare commercial TiO2 (P25) and graphene/spherical TiO2 nanocomposite with the same graphene content. Photocurrent experiments were performed, which demonstrate that the photocurrent of the graphene/rod-shaped TiO2 nanocomposite electrode is about 1.2 times as high as that of the graphene/spherical TiO2 nanocomposite electrode. The photocatalytic mechanism of graphene/rod-shaped TiO2 nanocomposite was also discussed on the basis of the experimental results. This work is anticipated to open a possibility in the integration of graphene and TiO2 with various morphologies for obtaining high-performance photocatalysts in addressing environmental protection issues.Graphene sheets were obtained through solvothermal reduction of colloidal dispersion of graphene oxide in benzyl alcohol. The graphene/rod-shaped TiO2 nanocomposite was synthesized by this novel and facile solvothermal method. During the solvothermal reaction, both the reduction of graphene oxide and the growth of rod-shaped TiO2 nanocrystals as well as its deposition on graphene occur simultaneously. The photocatalytic activity of graphene/rod-shaped TiO2 and graphene/spherical TiO2 nanocomposites was compared. In the photocatalytic degradation of methyl

  2. Microwave-Assisted Solvothermal Synthesis of VO2 Hollow Spheres and Their Conversion into V2O5 Hollow Spheres with Improved Lithium Storage Capability.

    Science.gov (United States)

    Pan, Jing; Zhong, Li; Li, Ming; Luo, Yuanyuan; Li, Guanghai

    2016-01-22

    Monodispersed hierarchically structured V2O5 hollow spheres were successfully obtained from orthorhombic VO2 hollow spheres, which are in turn synthesized by a simple template-free microwave-assisted solvothermal method. The structural evolution of VO2 hollow spheres has been studied and explained by a chemically induced self-transformation process. The reaction time and water content in the reaction solution have a great influence on the morphology and phase structure of the resulting products in the solvothermal reaction. The diameter of the VO2 hollow spheres can be regulated simply by changing vanadium ion content in the reaction solution. The VO2 hollow spheres can be transformed into V2O5 hollow spheres with nearly no morphological change by annealing in air. The nanorods composed of V2O5 hollow spheres have an average length of about 70 nm and width of about 19 nm. When used as a cathode material for lithium-ion batteries, the V2O5 hollow spheres display a diameter-dependent electrochemical performance, and the 440 nm hollow spheres show the highest specific discharge capacity of 377.5 mAhg(-1) at a current density of 50 mAg(-1) , and are better than the corresponding solid spheres and nanorod assemblies. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Synthesis of solvothermal derived TiO2 nanocrystals supported on ground nano egg shell waste and its utilization for the photocatalytic dye degradation

    Science.gov (United States)

    Singh, Rohini; Kumari, Pooja; Chavan, Prakash Dhondiram; Datta, Sudipta; Dutta, Suman

    2017-11-01

    TiO2 nanoparticles with excellent crystallinity were synthesized via solvothermal method and supported on the ground nano-sized egg shell waste at different loading concentrations. The photocatalytic degradation of the mixture of Methylene blue (MB) and Rhodamine 6G (Rh 6G) in aqueous solution utilizing prepared TiO2 nano composite under visible light irradiation was analysed. Different characterizations including UV-Visible (UV-Vis) spectroscopy, Field emission scanning electron microscopic (FE-SEM), energy dispersive studies (EDS), Transmission electron microscopy (TEM) were performed to investigate the physicochemical properties of the prepared catalyst. In addition, FE-SEM and EDS analysis of the prepared egg shell support were carried out to confirm the morphology, particle size distribution, and composition. The solvothermal derived TiO2 nanocrystals supported on ground nano-sized egg shell waste exhibited enhanced photocatalytic activity as compared to the as-prepared TiO2 nanoparticles. The synergistic effect of TiO2 nanoparticles and nano egg shell support is attributed to the effective dispersion of TiO2 that offers high specific surface area.

  4. Trisodium citrate-assisted synthesis of highly water-dispersible and superparamagnetic mesoporous Fe{sub 3}O{sub 4} hollow microspheres via solvothermal process

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Xi; Wang, Fumin; Cai, Wangfeng; Zhang, Xubin, E-mail: tjzxb@tju.edu.cn

    2015-07-05

    Highlights: • Mesoporous Fe{sub 3}O{sub 4} hollow microspheres were prepared by a facile trisodium citrate-assisted solvothermal method. • The product exhibits high water-dispersibility and superparamagnetism at room temperature. • Ostwald ripening process was responsible for the formation of hollow structures. • The Fe{sub 3}O{sub 4} hollow microspheres are ideal candidates for various biomedical applications. - Abstract: Highly water-dispersible and superparamagnetic mesoporous Fe{sub 3}O{sub 4} hollow microspheres were prepared by a facile trisodium citrate-assisted solvothermal method. The composition, morphology and structure of the product were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier-transform infrared (FT-IR) spectroscopy, thermogravimetric (TG) analysis, Brunauer–Emmett–Teller (BET) and vibrating sample magnetometer (VSM). The results showed that the obtained Fe{sub 3}O{sub 4} hollow microspheres were composed of nanoparticles about 21 nm in diameter and exhibited superparamagnetic properties with relatively high saturation magnetization at room temperature. Trisodium citrate played a crucial role as an electrostatic stabilizer in the formation of Fe{sub 3}O{sub 4} hollow microspheres and Ostwald ripening process was responsible for the formation of hollow structures. The Fe{sub 3}O{sub 4} hollow microspheres were mesoporous and highly water-dispersible, indicating that the Fe{sub 3}O{sub 4} hollow microspheres are ideal candidates for various biomedical applications.

  5. Solvothermal synthesis of Ni(HCO{sub 3}){sub 2}/graphene composites toward supercapacitors and the faradiac redox mechanism in KOH solution

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Jinfeng [State Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); University of Chinese Academy of Sciences, Beijing 100080 (China); Li, Zhangpeng [State Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); Wang, Jinqing, E-mail: jqwang@licp.cas.cn [State Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); Wang, Zhaofeng [State Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); Niu, Lengyuan; Gong, Peiwei [State Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); University of Chinese Academy of Sciences, Beijing 100080 (China); Liu, Xiaohong; Wang, Honggang [State Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); Yang, Shengrong, E-mail: sryang@licp.cas.cn [State Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000 (China)

    2013-12-25

    Highlights: •Ni(HCO{sub 3}){sub 2}/GS composites were prepared by a simple solvothermal method. •Ni(HCO{sub 3}){sub 2}/GS composites exhibited good supercapacitive performance. •Ni(HCO{sub 3}){sub 2}/GS2 presented the highest capacitance of 1200 F g{sup −1} at 4 A g{sup −1}. -- Abstract: In this work, a series of composites consisting of Ni(HCO{sub 3}){sub 2} and graphene nanosheets (GS) have been prepared by a facile solvothermal method, and then their application as electrode materials for supercapacitors has been investigated by cyclic voltammetry (CV) and galvanostatic charge–discharge tests. Morphological and structural analyses by field-emission scanning electron microscopy, high resolution transmission electron microscopy, X-ray diffraction and X-ray photoelectron spectroscopy indicated that Ni(HCO{sub 3}){sub 2} particles deposited on the GS and formed a loosely packed microstructure, actualizing the successful combination of Ni(HCO{sub 3}){sub 2} particles with GS. Among the prepared composites, the sample of Ni(HCO{sub 3}){sub 2}/GS2 exhibited the highest capacitance of 1200 F g{sup −1} at a current density of 4 A g{sup −1}, illustrating that such composite is a promising candidate as electrode material for supercapacitors. Moreover, the Faradic redox mechanism of the Ni(HCO{sub 3}){sub 2}/GS composite was further studied in virtue of XRD analysis, which revealed that the Ni(HCO{sub 3}){sub 2} phase could be quickly transformed into Ni(OH){sub 2} phase by an electrochemically induced phase transformation process during the galvanostatic charge–discharge tests.

  6. Synthesis of monodisperse MFe{sub 2}O{sub 4} (M = Fe and Zn) nanoparticles for polydiethylsiloxane-based ferrofluid with a solvothermal method

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Wei [State Key Laboratory of Optoelectronic Materials and Technologies, Guangdong Provincial Key Laboratory of Photovoltaics Technologies, School of Physics and Engineering, Sun Yat-Sen University, Guangzhou 510275 (China); Laboratory of Nanophotonic Functional Materials and Devices, Institute of Optoelectronic Materials and Technology, South China Normal University, Guangzhou 510631 (China); Zhuang, Lin, E-mail: stszhl@mail.sysu.edu.cn [State Key Laboratory of Optoelectronic Materials and Technologies, Guangdong Provincial Key Laboratory of Photovoltaics Technologies, School of Physics and Engineering, Sun Yat-Sen University, Guangzhou 510275 (China); Zhang, Yong [Laboratory of Nanophotonic Functional Materials and Devices, Institute of Optoelectronic Materials and Technology, South China Normal University, Guangzhou 510631 (China); Shen, Hui [State Key Laboratory of Optoelectronic Materials and Technologies, Guangdong Provincial Key Laboratory of Photovoltaics Technologies, School of Physics and Engineering, Sun Yat-Sen University, Guangzhou 510275 (China)

    2015-09-15

    Highlights: • MFe{sub 2}O{sub 4} nanoparticles were synthesized through a facile solvothermal method. • The relationship between viscosity and temperature of the polydiethylsiloxane-based ferrofluid is discussed. • Fe{sub 3}O{sub 4} nanoparticles have a saturation magnetization of 73.06 emu/g at room temperature. - Abstract: Monodisperse MFe{sub 2}O{sub 4} (M = Fe, Zn) nanoparticles were successfully synthesized for the application of polydiethylsiloxane-based (PDES) ferrofluids (FFs) via a novel solvothermal method, with which 1-octanol and 1-octanamine act as binary solvent, oleic acid (OA) as the surfactant and metal acetylacetonate [M(acac){sub 3}](M = Fe and Zn) as the metal source. X-ray diffractometer confirms that the resultant nanoparticles are pure MFe{sub 2}O{sub 4} with a spinel structure. Infrared spectroscopy indicates that oleic acid is bound to the surface of MFe{sub 2}O{sub 4} through a covalent bond between carboxylate (COO{sup −}) and metal cations. The ratio of 1-octanol and 1-octanamine plays a key role in the formation of the sphere-shaped morphology. Transmission electron microscopy (TEM) images confirm that the Fe{sub 3}O{sub 4} particles are of 4–11 nm with good monodispersity and a narrow size distribution. The saturation magnetization of Fe{sub 3}O{sub 4} nanoparticles with sizes of 7 nm can reach up to 73.06 emu/g. Polydiethylsiloxane-based (PDES) FFs show relatively smaller changes of the viscosity with low temperatures (from −7 to 20 °C) than the polydimethylsiloxane-based (PDMS) FFs. For FFs applications, the relationship between viscosity and temperature is also discussed.

  7. Solvothermal synthesis of MnFe{sub 2}O{sub 4}-graphene composite—Investigation of its adsorption and antimicrobial properties

    Energy Technology Data Exchange (ETDEWEB)

    Chella, Santhosh [Centre for Nanotechnology Research, VIT University, Vellore 632014 (India); Kollu, Pratap, E-mail: pk419@cam.ac.uk [Thin Film Magnetism Group, Cavendish Laboratory, Department of Physics, University of Cambridge, Cambridge CB3 0HE (United Kingdom); Komarala, Eswara Vara P R; Doshi, Sejal [Department of Metallurgical Engineering and Materials Science, Indian Institute of Technology Bombay, Mumbai (India); Saranya, Murugan; Felix, Sathiyanathan; Ramachandran, Rajendran [Centre for Nanotechnology Research, VIT University, Vellore 632014 (India); Saravanan, Padmanapan [Defence Metallurgical Research Laboratory, Hyderabad 5000058 (India); Koneru, Vijaya Lakshmi [Development Alternatives, Qutub Institutional Area, New Delhi 110016 (India); Venugopal, Velmurugan [Centre for Nanotechnology Research, VIT University, Vellore 632014 (India); Jeong, Soon Kwan [Climate Change Technology Research Division, Korea Institute of Energy Research, Yuseong-gu, Daejeon 305-343 (Korea, Republic of); Nirmala Grace, Andrews, E-mail: anirmalagrace@vit.ac.in [Centre for Nanotechnology Research, VIT University, Vellore 632014 (India)

    2015-02-01

    Graphical abstract: - Highlights: • Graphene manganese ferrite composite was synthesized by a solvothermal process. • Adsorption of Pb and Cd metal ions were tested with MnFe{sub 2}O{sub 4}-G material. • The MnFe{sub 2}O{sub 4}-G material showed good adsorption capacity for metal ions. • MnFe{sub 2}O{sub 4}-G showed the higher antibacterial activity of 82%, than graphene. - Abstract: Graphene manganese ferrite (MnFe{sub 2}O{sub 4}-G) composite was prepared by a solvothermal process. The as-prepared graphene manganese ferrite composite was tested for the adsorption of lead (Pb(II)) and cadmium (Cd(II)) ions by analytical methods under diverse experimental parameters. With respect to contact time measurements, the adsorption of Pb and Cd ions increased and reached equilibrium within 120 and 180 min at 37 °C with a maximum adsorption at pH 5 and 7 respectively. The Langmuir model correlates to the experimental data showing an adsorption capacity of 100 for Pb(II) and 76.90 mg g{sup −1} for Cd(II) ions. Thermodynamic studies revealed that the adsorption of Pb and Cd ions onto MnFe{sub 2}O{sub 4}-G was spontaneous, exothermic and feasible in the range of 27–47 °C. Cytotoxicity behavior of graphene against bacterial cell membrane is well known. To better understand its antimicrobial mechanism, the antibacterial activity of graphene and MnFe{sub 2}O{sub 4}-G nanocomposite was compared. Under similar concentration and incubation conditions, nanocomposite MnFe{sub 2}O{sub 4}-G dispersion showed the highest antibacterial activity of 82%, as compared to graphene showing 37% cell loss. Results showed that the prepared composite possess good adsorption efficiency and thus could be considered as an excellent material for removal of toxic heavy metal ions as explained by adsorption isotherm. Hence MnFe{sub 2}O{sub 4}-G can be used as an adsorbent as well as an antimicrobial agent.

  8. Solvothermal synthesis of Mg-doped Li2FeSiO4/C nanocomposite cathode materials for lithium-ion batteries

    Science.gov (United States)

    Kumar, Ajay; Jayakumar, O. D.; Naik, V. M.; Nazri, G. A.; Naik, R.

    Lithium transition metal orthosilicates, such as Li2FeSiO4 and Li2MnSiO4, as cathode material have attracted much attention lately due to their high theoretical capacity ( 330 mAh/g), low cost, and environmental friendliness. However, they suffer from poor electronic conductivity and slow lithium ion diffusion in the solid phase. Several cation-doped orthosilicates have been studied to improve their electrochemical performance. We have synthesized partially Mg-substituted Li2Mgx Fe1-x SiO4-C, (x = 0.0, 0.01, 0.02, and 0.04) nano-composites by solvothermal method followed by annealing at 600oC in argon flow. The structure and morphology of the composites were characterized by XRD, SEM and TEM. The surface area and pore size distribution were measured by using N2 adsorption/desorption curves. The electrochemical performance of the Li2MgxFe1-x SiO4-C composites was evaluated by Galvanostatic cycling against metallic lithium anode, electrochemical impedance spectroscopy, and cyclic voltammetry. Li2Mg0.01Fe0.99SiO4-C sample shows a capacity of 278 mAh/g (at C/30 rate in the 1.5-4.6 V voltage window) with an excellent rate capability and stability, compared to the other samples. We attribute this observation to its higher surface area, enhanced electronic conductivity and higher lithium ion diffusion coefficient.

  9. Solvothermal Synthesis of a Hollow Micro-Sphere LiFePO₄/C Composite with a Porous Interior Structure as a Cathode Material for Lithium Ion Batteries.

    Science.gov (United States)

    Liu, Yang; Zhang, Jieyu; Li, Ying; Hu, Yemin; Li, Wenxian; Zhu, Mingyuan; Hu, Pengfei; Chou, Shulei; Wang, Guoxiu

    2017-11-03

    To overcome the low lithium ion diffusion and slow electron transfer, a hollow micro sphere LiFePO₄/C cathode material with a porous interior structure was synthesized via a solvothermal method by using ethylene glycol (EG) as the solvent medium and cetyltrimethylammonium bromide (CTAB) as the surfactant. In this strategy, the EG solvent inhibits the growth of the crystals and the CTAB surfactant boots the self-assembly of the primary nanoparticles to form hollow spheres. The resultant carbon-coat LiFePO₄/C hollow micro-spheres have a ~300 nm thick shell/wall consisting of aggregated nanoparticles and a porous interior. When used as materials for lithium-ion batteries, the hollow micro spherical LiFePO₄/C composite exhibits superior discharge capacity (163 mAh g-1 at 0.1 C), good high-rate discharge capacity (118 mAh g-1 at 10 C), and fine cycling stability (99.2% after 200 cycles at 0.1 C). The good electrochemical performances are attributed to a high rate of ionic/electronic conduction and the high structural stability arising from the nanosized primary particles and the micro-sized hollow spherical structure.

  10. Ultrasonically assisted solvothermal synthesis of novel Ni/Al layered double hydroxide for capturing of Cd(II) from contaminated water

    Science.gov (United States)

    Rahmanian, Omid; Maleki, Mohammad Hassan; Dinari, Mohammad

    2017-11-01

    A novel adsorbent of nickel aluminum layered double hydroxide (Ni/Al-LDH) was prepared through the precipitation of metal nitrates by ultrasonically assisted solvothermal method. The surface morphology, chemical structure and thermal properties of this compound were examined by X-ray diffraction (XRD), Fourier Transform Infrared (FT-IR), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), and thermogravimetric analysis (TGA) techniques. The XRD, TEM and FE-SEM results established that the synthesized LDH have a well-ordered layer structure with good crystalline nature. Then it was applied to remove excessive Cd(II) ions from water and the effects of contact time, pH and adsorbent dose were examined at initial Cd(II) concentration of 10 mg/L. Results show that the time required to reach equilibrium was fast (40 min) and working pH solution was neutral (pH 7). Langmuir and Freundlich model of adsorption isotherms were explored; the results show that the Freundlich model was better fitted than that Langmuir model. This results predicting a multilayer adsorption of Cd(II) on LDH. The equilibrium kinetic adsorption data were fixed to the pseudo-second order kinetic equation.

  11. Solvothermal Synthesis of Hierarchical TiO2Microstructures with High Crystallinity and Superior Light Scattering for High-Performance Dye-Sensitized Solar Cells.

    Science.gov (United States)

    Li, Zhao-Qian; Mo, Li-E; Chen, Wang-Chao; Shi, Xiao-Qiang; Wang, Ning; Hu, Lin-Hua; Hayat, Tasawar; Alsaedi, Ahmed; Dai, Song-Yuan

    2017-09-20

    In this article, hierarchical TiO 2 microstructures (HM-TiO 2 ) were synthesized by a simple solvothermal method adopting tetra-n-butyl titanate as the titanium source in a mixed solvent composed of N,N-dimethylformamide and acetic acid. Due to the high crystallinity and superior light-scattering ability, the resultant HM-TiO 2 are advantageous as photoanodes for dye-sensitized solar cells. When assembled to the entire photovoltaic device with C101 dye as a sensitizer, the pure HM-TiO 2 -based solar cells showed an ultrahigh photovoltage up to 0.853 V. Finally, by employing the as-obtained HM-TiO 2 as the scattering layer and optimizing the architecture of dye-sensitized solar cells, both higher photovoltage and incident photon-to-electron conversion efficiency value were harvested with respect to TiO 2 nanoparticles-based dye-sensitized solar cells, resulting in a high power conversion efficiency of 9.79%. This work provides a promising strategy to develop photoanode materials with outstanding photoelectric conversion performance.

  12. Solvothermal Synthesis of Ternary Sulfides of Sb2 − x Bi x S3(x = 0.4, 1 with 3D Flower-Like Architectures

    Directory of Open Access Journals (Sweden)

    Wang Guoxiu

    2009-01-01

    Full Text Available Abstract Flower-like nanostructures of Sb2 − x Bi x S3(x = 0.4, 1.0 were successfully prepared using both antimony diethyldithiocarbamate [Sb(DDTC3] and bismuth diethyldithiocarbamate [Bi(DDTC3] as precursors under solvothermal conditions at 180 °C. The prepared Sb2 − x Bi x S3 with flower-like 3D architectures were characterized by X-ray diffraction (XRD, scanning electron microscopy (SEM, energy dispersive X-ray spectrometry (EDS, high-resolution transmission electron microscopy (HRTEM, and selected area electron diffraction (SAED. The flower-like architectures, with an average diameter of ~4 μm, were composed of single-crystalline nanorods with orthorhombic structures. The optical absorption properties of the Sb2 − x Bi x S3 nanostructures were investigated by UV–Visible spectroscopy, and the results indicate that the Sb2 − x Bi x S3 compounds are semiconducting with direct band gaps of 1.32 and 1.30 eV for x = 0.4 and 1.0, respectively. On the basis of the experimental results, a possible growth mechanism for the flower-like Sb2 − x Bi x S3 nanostructures is suggested.

  13. Unique and facile solvothermal synthesis of mesoporous WO3 using a solid precursor and a surfactant template as a photoanode for visible-light-driven water oxidation

    Science.gov (United States)

    2014-01-01

    Mesoporous tungsten trioxide (WO3) was prepared from tungstic acid (H2WO4) as a tungsten precursor with dodecylamine (DDA) as a template to guide porosity of the nanostructure by a solvothermal technique. The WO3 sample (denoted as WO3-DDA) prepared with DDA was moulded on an electrode to yield efficient performance for visible-light-driven photoelectrochemical (PEC) water oxidation. Powder X-ray diffraction (XRD) data of the WO3-DDA sample calcined at 400°C indicate a crystalline framework of the mesoporous structure with disordered arrangement of pores. N2 physisorption studies show a Brunauer-Emmett-Teller (BET) surface area up to 57 m2 g-1 together with type IV isotherms and uniform distribution of a nanoscale pore size in the mesopore region. Scanning electron microscopy (SEM) images exhibit well-connected tiny spherical WO3 particles with a diameter of ca. 5 to 20 nm composing the mesoporous network. The WO3-DDA electrode generated photoanodic current density of 1.1 mA cm-2 at 1.0 V versus Ag/AgCl under visible light irradiation, which is about three times higher than that of the untemplated WO3. O2 (1.49 μmol; Faraday efficiency, 65.2%) was evolved during the 1-h photoelectrolysis for the WO3-DDA electrode under the conditions employed. The mesoporous electrode turned out to work more efficiently for visible-light-driven water oxidation relative to the untemplated WO3 electrode. PMID:25313301

  14. Facile synthesis of zinc oxide nanoparticles decorated graphene oxide composite via simple solvothermal route and their photocatalytic activity on methylene blue degradation.

    Science.gov (United States)

    Atchudan, Raji; Edison, Thomas Nesakumar Jebakumar Immanuel; Perumal, Suguna; Karthikeyan, Dhanapalan; Lee, Yong Rok

    2016-09-01

    Zinc oxide nanoparticles decorated graphene oxide (ZnO@GO) composite was synthesized by simple solvothermal method where zinc oxide (ZnO) nanoparticles and graphene oxide (GO) were synthesized via simple thermal oxidation and Hummers method, respectively. The obtained materials were thoroughly characterized by various physico-chemical techniques such as X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, field emission scanning electron microscopy (FESEM), high resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), and Raman spectroscopy. Raman spectrum shows the intensity of D to G value was close to one which confirms the obtained GO and ZnO@GO composite possesses moderate graphitization. TEM images shows the ZnO nanoparticles mean size of 15±5nm were dispersed over the wrinkled graphene layers. The photocatalytic performance of ZnO@GO composite on degradation of methylene blue (MB) is investigated and the results show that the GO plays an important role in the enhancement of photocatalytic performance. The synthesized ZnO@GO composite achieves a maximum degradation efficiency of 98.5% in a neutral solution under UV-light irradiation for 15min as compared with pure ZnO (degradation efficiency is 49% after 60min of irradiation) due to the increased light absorption, the reduced charge recombination with the introduction of GO. Moreover, the resulting ZnO@GO composite possesses excellent degradation efficiency as compared to ZnO nanoparticles alone on MB. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. One-pot solvothermal synthesis of three-dimensional (3D) BiOI/BiOCl composites with enhanced visible-light photocatalytic activities for the degradation of bisphenol-A

    Energy Technology Data Exchange (ETDEWEB)

    Xiao, Xin [School of Chemistry and Environment, South China Normal University, Key Lab of Theoretical Chemistry of Environment, Guangzhou 510006 (China); Nano Science Research Center, School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou 510640 (China); Hao, Rong; Liang, Min; Zuo, Xiaoxi [School of Chemistry and Environment, South China Normal University, Key Lab of Theoretical Chemistry of Environment, Guangzhou 510006 (China); Nan, Junmin, E-mail: jmnan@scnu.edu.cn [School of Chemistry and Environment, South China Normal University, Key Lab of Theoretical Chemistry of Environment, Guangzhou 510006 (China); Li, Laisheng [School of Chemistry and Environment, South China Normal University, Key Lab of Theoretical Chemistry of Environment, Guangzhou 510006 (China); Zhang, Weide [Nano Science Research Center, School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou 510640 (China)

    2012-09-30

    Highlights: Black-Right-Pointing-Pointer Synthesis of 3D BiOI/BiOCl microspheres by a one-pot template-free solvothermal method. Black-Right-Pointing-Pointer Photocatalyst is BiOI/BiOCl composites. Black-Right-Pointing-Pointer BiOI/BiOCl composites have enhanced visible-light photocatalytic ability to bisphenol-A. Black-Right-Pointing-Pointer A simple and direct photodegradation pathway of bisphenol-A is proposed. - Abstract: Three-dimensional (3D) BiOI/BiOCl composite microspheres with enhanced visible-light photodegradation activity of bisphenol-A (BPA) are synthesized by a simple, one-pot, template-free, solvothermal method using BiI{sub 3} and BiCl{sub 3} as precursors. These 3D hierarchical microspheres with heterojunction structures are composed of 2D nanosheets and have composition-dependent absorption properties in the ultraviolet and visible light regions. The photocatalytic oxidation of BPA over BiOI/BiOCl composites followed pseudo first-order kinetics according to the Langmuir-Hinshelwood model. The highest photodegradation efficiency of BPA, i.e., nearly 100%, was observed with the BiOI/BiOCl composite (containing 90% BiOI) using a catalyst dosage of 1 g L{sup -1} in the BPA solution (C{sub 0} = 20 mg L{sup -1}, pH = 7.0) under visible light irradiation for 60 min. Under these conditions, the reaction rate constant was more than 4 and 20 times greater than that of pure BiOI and the commercially available Degussa P25, respectively. The superior photocatalytic activity of this composite catalyst is attributed to the suitable band gap energies and the low recombination rate of the photogenerated electron-hole pairs due to the presence of BiOI/BiOCl heterostructures. Only one intermediate at m/z 151 was observed in the photodegradation process of BPA by liquid chromatography combined with mass spectrometry (LC-MS) analysis, and a simple and hole-predominated photodegradation pathway of BPA was subsequently proposed. Furthermore, this photocatalyst

  16. The Synthesis of the Hierarchical Structure of Information Resources for Management of Electronic Commerce Entities

    Directory of Open Access Journals (Sweden)

    Krutova Anzhelika S.

    2017-06-01

    Full Text Available The aim of the article is to develop the theoretical bases for the classification and coding of economic information and the scientific justification of the content of information resources of an electronic commerce enterprise. The essence of information resources for management of electronic business entities is investigated. It is proved that the organization of accounting in e-commerce systems is advisable to be built on the basis of two circuits: accounting for financial flows and accounting associated with transformation of business factors in products and services as a result of production activities. There presented a sequence of accounting organization that allows to combine the both circuits in a single information system, which provides a possibility for the integrated replenishment and distributed simultaneous use of the e-commerce system by all groups of users. It is proved that the guarantee of efficient activity of the information management system of electronic commerce entities is a proper systematization of the aggregate of information resources on economic facts and operations of an enterprise in accordance with the management tasks by building the hierarchy of accounting nomenclatures. It is suggested to understand nomenclature as an objective, primary information aggregate concerning a certain fact of the economic activity of an enterprise, which is characterized by minimum requisites, is entered into the database of the information system and is to be reflected in the accounting system. It is proposed to build a database of e-commerce systems as a part of directories (constants, personnel, goods / products, suppliers, buyers and the hierarchy of accounting nomenclatures. The package of documents regulating the organization of accounting at an enterprise should include: the provision on the accounting services, the order on the accounting policy, the job descriptions, the schedules of information exchange, the report card and

  17. Solvothermal synthesis of Fe{sub 7}C{sub 3} and Fe{sub 3}C nanostructures with phase and morphology control

    Energy Technology Data Exchange (ETDEWEB)

    Williams, Brent; Clifford, Dustin; Carpenter, Everett E., E-mail: aelgendy@vcu.edu, E-mail: ecarpenter2@vcu.edu [Department of Chemistry, Virginia Commonwealth University, Richmond, Virginia 23284 (United States); El-Gendy, Ahmed A., E-mail: aelgendy@vcu.edu, E-mail: ecarpenter2@vcu.edu [Department of Chemistry, Virginia Commonwealth University, Richmond, Virginia 23284 (United States); Nanotechnology and Nanometrology Laboratory, National Institute for Standards, Giza 12211 (Egypt)

    2016-07-21

    A phase transition, from orthorhombic Fe{sub 3}C to hexagonal Fe{sub 7}C{sub 3}, was observed using a wet synthesis mediated by hexadecyltrimethylammonium chloride (CTAC). In this study, CTAC has been shown to control carbide phase, morphology, and size of the iron carbide nanostructures. Fe{sub 7}C{sub 3} hexagonal prisms were formed with an average diameter of 960 nm, the thickness of 150 nm, and Fe{sub 3}C nanostructures with an approximate size of 50 nm. Magnetic studies show ferromagnetic behavior with M{sub s} of 126 emu/g, and H{sub c} of 170 Oe with respect to Fe{sub 7}C{sub 3} and 95 emu/g and 590 Oe with respect to Fe{sub 3}C. The thermal studies using high temperature x-ray diffraction show stability of Fe{sub 7}C{sub 3} up to 500 °C. Upon slow cooling, the Fe{sub 7}C{sub 3} phase is recovered with an intermediate oxide phase occurring around 300 °C. This study has demonstrated a simple route in synthesizing iron carbides for an in depth magnetic study and crystal phase transition study of Fe{sub 7}C{sub 3} at elevated temperatures.

  18. Hierarchical structures of ZnO spherical particles synthesized solvothermally

    Directory of Open Access Journals (Sweden)

    Noriko Saito and Hajime Haneda

    2011-01-01

    Full Text Available We review the solvothermal synthesis, using a mixture of ethylene glycol (EG and water as the solvent, of zinc oxide (ZnO particles having spherical and flower-like shapes and hierarchical nanostructures. The preparation conditions of the ZnO particles and the microscopic characterization of the morphology are summarized. We found the following three effects of the ratio of EG to water on the formation of hierarchical structures: (i EG restricts the growth of ZnO microcrystals, (ii EG promotes the self-assembly of small crystallites into spheroidal particles and (iii the high water content of EG results in hollow spheres.

  19. Phase controlled solvothermal synthesis of Cu{sub 2}ZnSnS{sub 4}, Cu{sub 2}ZnSn(S,Se){sub 4} and Cu{sub 2}ZnSnSe{sub 4} Nanocrystals: The effect of Se and S sources on phase purity

    Energy Technology Data Exchange (ETDEWEB)

    Pal, Mou [Instituto de Energías Renovables, Universidad Nacional Autónoma de México, 62580 Temixco, Morelos (Mexico); Instituto de Física, BUAP, Av. San Claudio y Blvd. 18 Sur Col. San Manuel, Ciudad Universitaria, C.P. 72570, Puebla (Mexico); Mathews, N.R. [Instituto de Energías Renovables, Universidad Nacional Autónoma de México, 62580 Temixco, Morelos (Mexico); Paraguay-Delgado, F. [Departamento de Materiales Nanoestructurados, Centro de Investigación en Materiales Avanzados (CIMAV), Chihuahua (Mexico); Mathew, X., E-mail: xm@ier.unam.mx [Instituto de Energías Renovables, Universidad Nacional Autónoma de México, 62580 Temixco, Morelos (Mexico)

    2015-09-15

    In this study, we have reported the synthesis of Cu{sub 2}ZnSnSe{sub 4} (CZTSe), Cu{sub 2}ZnSnS{sub 4} (CZTS) and Cu{sub 2}ZnSn(S,Se){sub 4} (CZTSSe) nanocrystals with tunable band gap and composition obtained by solvothermal method. The crystalline structure, composition, morphology and optical properties of the nanoparticles were characterized by X-ray diffraction (XRD), Raman scattering, energy dispersive X-ray spectroscopy, transmission electron microscopy and diffuse reflectance (DR) spectroscopy. While the XRD patterns of CZTS and CZTSe nanoparticles prepared with elemental S/Se powder revealed the presence of phase pure nanoparticles, the CZTSSe nanoparticles obtained using a mixture of S and Se, were found to contain many secondary phases under the same synthesis protocol. Formation of impurity phases in CZTSSe sample, can be avoided by using a mixture of 1-dodecanethiol (DT; CH{sub 3}(CH{sub 2}){sub 11}SH)/oleylamine (OLA) instead of S powder and following the same experimental procedure. The incorporation of S in CZTSe nanocrystals prepared in presence of DDT/OLA mixture was confirmed through structural and optical characterizations. The optical properties of the quaternary chalcogenide nanocrystals were found to vary with the chemical composition of the material. - Highlights: • Solvothermal synthesis of CZTS, CZTSSe and CZTSe nanocrystals and discussion on possible formation mechanism. • Use of dodecanethiol/oleylamine mixture to synthesize phase-pure CZTSSe nanocrystals. • Formation of impurity phases can be controlled with proper S and Se sources.

  20. Homoleptic platinum(II) and palladium(II) organothiolates and phenylselenolates: solvothermal synthesis, structural determination, optical properties, and single-source precursors for PdSe and PdS nanocrystals.

    Science.gov (United States)

    Chui, Stephen Sin-Yin; Low, Kam-Hung; Lu, Jun; Roy, V A L; Chan, Sharon Lai-Fung; Che, Chi-Ming

    2010-09-03

    Homoleptic d(8)-metal organothiolates and phenylselenolates [M(EC(6)H(5))(2)](infinity) (E=S, M=Pt 1, M=Pd 2, M=Ni 5; E=Se, M=Pt 3, M=Pd 4) were prepared as crystalline solids under solvothermal conditions. Their structures were solved using powder X-ray diffraction data. In each case, the EC(6)H(5) (E=S, Se) ligand binds to two metal ions (M=Pt, Pd, and Ni) to form chain-like structures with planar (in 1) or zig-zag (in 2-5) conformations. The [M(SR)(2)](infinity) complexes (M=Pt, R=4-tert-butylphenyl 6; R=2-naphthyl 8; R=4-nitrophenyl 10 and M=Pd, R=4-tert-butylphenyl 7; R=2-naphthyl 9; R=4-nitrophenyl 11) were prepared under similar solvothermal conditions. Based on the XPS binding energies and elemental analyses, complexes 6-11 have the same [M(SR)(2)](infinity) formulation as 1 and 2. The cyclic complex [Pd(6)(SCH(3))(12)] 12 was prepared as a crystalline solid by solvothermal annealing treatment of the amorphous precipitate. A chain-like polymer structure is proposed for both [Pd(SC(12)H(25))(2)](infinity) 13 and [Pd(SC(16)H(33))(2)](infinity) 14; these polymeric chains self-assemble to give layer-like structures. Solid-state diffuse reflectance spectra reveal that the optical band gap E(g) (eV) of complexes 1, 6, 8, 10 and of 2, 7, 9, 11 are in the range of 2.10-3.00 eV and 2.10-2.63 eV, respectively, and 5 has the lowest E(g) value (1.72 eV). Heating solid samples of 4 and 13 under solvothermal conditions afforded phase-pure Pd(17)Se(15) and PdS nanocrystals, respectively. Field-effect transistors fabricated with a drop-cast thin film made from Pd(17)Se(15) nanocrystals prior treated with an ethanolic solution of 1-hexadecanethiol displayed ambipolar charge transporting properties with hole and electron mobility being 7x10(-2) cm(2) V(-1) s(-1) and 6x10(-2) cm(2) V(-1) s(-1), respectively.

  1. Solvothermal chemistry of luminescent lanthanide fluorides

    OpenAIRE

    Jayasundera, Anil

    2009-01-01

    Exploration of novel lanthanide fluoride framework materials in inorganic-organic hybrid systems under solvothermal conditions towards development of new luminescent materials is discussed. X-ray single crystal and powder diffraction methods have been used as crystallographic characterisation techniques. Determination and study of luminescence properties for selected hybrid materials has also been carried out. The first organically templated luminescent lanthanide fluoride fram...

  2. Solvothermal syntheses, crystal structures, optical and thermal ...

    Indian Academy of Sciences (India)

    Keywords. Selenidogermanates; nickel; solvothermal syntheses; crystal structures; optical properties ... The different coordination environments of Ni²⁺ ions indicate the influence of the denticity of ethylene polyamines on the formation of selenidogermanates in the presence of transition metal ions. Thecompounds 1–3 ...

  3. Solvothermal preparation of micro/nanostructured TiO{sub 2} with enhanced lithium storage capability

    Energy Technology Data Exchange (ETDEWEB)

    Li, Jie [School of Physics and Mechanical & Electronical Engineering, Hubei University of Education, Wuhan, 430205 (China); Wang, Chao [Department of Architecture and Material Engineering, Hubei University of Education, Wuhan, 430205 (China); Zheng, Ping; Zhang, Lei; Chen, Gongxuan [College of Chemistry and Life Science, Hubei University of Education, Wuhan, 430205 (China); Tang, Chengchun [School of Materials Science and Engineering, Hebei University of Technology, Tianjin 300130 (China); Wu, Tian, E-mail: twu@whu.edu.cn [School of Physics and Mechanical & Electronical Engineering, Hubei University of Education, Wuhan, 430205 (China); College of Chemistry and Life Science, Hubei University of Education, Wuhan, 430205 (China); Department of Architecture and Material Engineering, Hubei University of Education, Wuhan, 430205 (China)

    2017-04-01

    Facile and controllable preparation of TiO{sub 2} is of prime importance to elaborately tailor and then fully exploit its intriguing functionalities in energy storage, catalysis and environmental remediation. Herein, a solvothermal method combined with post annealing is conducted, in which the hydrolysis of tetrabutyl titanate is controlled by the in-situ generated water during solvothermal treatment. By controlling synthetic conditions (i.e. reactant ratio, solvothermal temperature and reaction time), we manage to tailor the morphologies of TiO{sub 2}. Specially, three typical structures (nanoparticle, nanoneedle and nanorod) are studied to reveal the growth mechanism and the effects of the synthesis conditions. Nanoneedle-structured TiO{sub 2} shows higher specific capacity and enhanced cycle stability as anode material for lithium ion batteries. - Highlights: • Controllable preparation of nano-TiO{sub 2} is achieved by a solvothermal method. • TiO{sub 2} morphology is tailored by tuning reactant ratio, temperature and duration. • Needle structured TiO{sub 2} shows enhanced lithium storage capability.

  4. Semantic Entities

    NARCIS (Netherlands)

    Van Gysel, C.; de Rijke, M.; Worring, M.

    2015-01-01

    Entity retrieval has seen a lot of interest from the research community over the past decade. Ten years ago, the expertise retrieval task gained popularity in the research community during the TREC Enterprise Track [10]. It has remained relevant ever since, while broadening to social media, to

  5. The synthesis of novel LiNiPO4 core and Co3O4/CoO shell materials by combining them with hard-template and solvothermal routes.

    Science.gov (United States)

    Örnek, Ahmet

    2017-10-15

    Pure CoO and Co3O4 surface-modified LiNiPO4 nanoscale powders are successfully synthesized for the first time by newly elaborated hard-template and solvothermal methods. Using this extraordinary technique, LiNiPO4 particles are coated with a thin CoO or Co3O4 layer with a perfect core-shell morphology. The technique's positive contribution to electrochemistry is investigated in detail. The HR-TEM analysis proves that it possible to achieve a continuous surface coverage of about 5nm, a result that contributes towards solving the chronic electrochemical problems of high-voltage cathode material. Our data reveal that cobalt cannot be diffused into the LiNiPO4 crystal system during the calcination process and that the LiNiPO4@CoO cathode demonstrates superior cycle stability and specific capacity at relatively low rates. The LiNiPO4@CoO cathode exhibits the best electrochemical properties, achieving a discharge capacity of 149mAhg(-1) at 0.1C rate, and shows almost 82% capacity retention after 80 charge-discharge cycles. It therefore achieves partial success in terms of improving the electrochemical properties of the LiNiPO4 cathode material. This is especially crucial for energy storage with regard to electric vehicles and plug-in hybrid electric applications. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. Morphology-controlled microwave-assisted solvothermal synthesis of high-performance LiCoPO4 as a high-voltage cathode material for Li-ion batteries

    Science.gov (United States)

    Ludwig, Jennifer; Marino, Cyril; Haering, Dominik; Stinner, Christoph; Gasteiger, Hubert A.; Nilges, Tom

    2017-02-01

    High-performance particles of the high-voltage cathode material LiCoPO4 for Li-ion batteries are synthesized by a simple and rapid one-step microwave-assisted solvothermal route at moderate temperatures (250 °C). Using a variety of water/alcohol 1:1 (v:v) solvent mixtures, including ethylene glycol (EG), diethylene glycol (DEG), triethylene glycol (TEG), tetraethylene glycol (TTEG), polyethylene glycol 400 (PEG), and benzyl alcohol (BA), the focus of the study is set on optimizing the electrochemical performance of the material by controlling the particle size and morphology. Scanning electron microscopy studies reveal a strong influence of the co-solvent on the particle size and morphology, resulting in the formation of variations between square, rhombic and hexagonal platelets. According to selected area electron diffraction experiments, the smallest crystal dimension is in the [010] direction for all materials, which is along the lithium diffusion pathways of the olivine crystal structure. The anisotropic crystal orientations with enhanced Li-ion diffusion properties result in high initial discharge capacities and gravimetric energy densities (up to 141 mAh g-1 at 0.1 C and 677 Wh kg-1 for LiCoPO4 obtained from TEG), excellent rate capabilities, and cycle life for 20 cycles.

  7. Controllable solvothermal synthesis and photocatalytic properties of complex (oxy)fluorides K2TiOF4, K3TiOF5, K7Ti4O4F7 and K2TiF6.

    Science.gov (United States)

    Sheng, Jie; Tang, Kaibin; Cheng, Wei; Wang, Junli; Nie, Yanxiang; Yang, Qing

    2009-11-15

    Complex (oxy)fluorides K(2)TiF(6), K(2)TiOF(4), K(3)TiOF(5) and K(7)Ti(4)O(4)F(7) have been successfully synthesized for the first time through a controllable solvothermal route involving different solvents, for example, methanol, methanol-H(2)O and methanol-H(2)O(2). The as-prepared products were characterized by X-ray powder diffraction, N(2) surface area adsorption, scanning electron microscope, Fourier transform infrared spectroscopy, UV-vis absorption spectra and X-ray fluorescence. The influences of reaction conditions such as the ratio of methanol to H(2)O(2) or methanol to H(2)O, reaction temperature on the phase, crystallizability and purity of the (oxy)fluorides products were discussed in detail. Meanwhile, the photocatalytic behaviors of the as-prepared K(2)TiF(6), K(2)TiOF(4), K(3)TiOF(5) and K(7)Ti(4)O(4)F(7) were evaluated by degradation of rhodamine B molecules, and the results showed that all of the products possessed photocatalytic activities in the order of K(2)TiOF(4)>K(2)TiF(6)>K(7)Ti(4)O(4)F(7)>K(3)TiOF(5) at room temperature under the UV light.

  8. Solvothermal synthesis of discrete cages and extended networks comprising {Cr(III)3O(O2CR)3(oxime)3}2- (R = H, CH3, C(CH3)3, C14H9) building blocks

    DEFF Research Database (Denmark)

    Houton, Edel; Comar, Priyanka; Pitak, Mateusz B.

    2016-01-01

    The synthesis, structural and magnetic characterisation of a family of related Cr(iii) cages are reported. Each member comprises {Cr(iii)3O(O2CR1)3(R2-sao)3}2- (R1 = H, CH3, C(CH3)3, C14H9; R2 = Me, Ph, tBu, C10H8) triangles linked by Na+ cations, resulting in either the discrete complexes [H3O][...

  9. Defect chemistry of phospho-olivine nanoparticles synthesized by a microwave-assisted solvothermal process

    Energy Technology Data Exchange (ETDEWEB)

    Bridges, Craig A., E-mail: bridgesca@ornl.gov [Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States); Harrison, Katharine L. [Electrochemical Energy Laboratory and Department of Mechanical Engineering, The University of Texas at Austin, Austin, TX 78712 (United States); Unocic, Raymond R.; Idrobo, Juan-Carlos [Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States); Parans Paranthaman, M. [Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States); Manthiram, Arumugam [Electrochemical Energy Laboratory and Department of Mechanical Engineering, The University of Texas at Austin, Austin, TX 78712 (United States)

    2013-09-15

    Nanocrystalline LiFePO{sub 4} powders synthesized by a microwave-assisted solvothermal (MW-ST) process have been structurally characterized with a combination of high resolution powder neutron diffraction, synchrotron X-ray diffraction, and aberration-corrected HAADF STEM imaging. A significant level of defects has been found in the samples prepared at 255 and 275 °C. These temperatures are significantly higher than what has previously been suggested to be the maximum temperature for defect formation in LiFePO{sub 4}, so the presence of defects is likely related to the rapid MW-ST synthesis involving a short reaction time (∼5 min). A defect model has been tentatively proposed, though it has been shown that powder diffraction data alone cannot conclusively determine the precise defect distribution in LiFePO{sub 4} samples. The model is consistent with other literature reports on nanopowders synthesized at low temperatures, in which the unit cell volume is significantly reduced relative to defect-free, micron-sized LiFePO{sub 4} powders. - Graphical abstract: Temperature-dependent antisite defect formation has been observed in nanocrystalline LiFePO{sub 4} powders synthesized by a microwave solvothermal process, using high resolution diffraction and STEM imaging. Display Omitted - Highlights: • LiFePO{sub 4} nanopowders synthesized by a microwave-assisted solvothermal process. • Defects directly observed by aberration-corrected HAADF STEM imaging. • Antisite defects present from synthesis at 255 and 275 °C. • Defects present from higher temperature synthesis than previously reported. • Powder diffraction data have been analyzed in detail for various defect models.

  10. Solvothermal tuning of photoluminescent graphene quantum dots: from preparation to photoluminescence mechanism

    Science.gov (United States)

    Qi, Bao-Ping; Zhang, Xiaoru; Shang, Bing-Bing; Xiang, Dongshan; Zhang, Shenghui

    2018-02-01

    Solvothermal synthesis was employed to tune the surface states of graphene quantum dots (GQDs). Two series of GQDs with the particle sizes from 2.6 to 4.5 nm were prepared as follows: (I) GQDs with the same size but different oxygen degrees; (II) GQDs with different core sizes but the similar surface chemistry. Both the large sizes and the high surface oxidation degrees led to the redshift photoluminescence (PL) of GQDs. Electrochemiluminescence (ECL) spectra from two series of GQDs were all in accordance with their PL spectra, respectively, which provided good evidence for the conjugated structures in GQDs responsible for PL. [Figure not available: see fulltext.

  11. Effect of temperature and time on solvothermal synthesis of ...

    Indian Academy of Sciences (India)

    1School of Chemical and Materials Engineering, National University of Science and Technology, H/12 Islamabad, Pakistan. 2Austrian Institute of ... multilayers ceramic capacitors to achieve device miniaturi- zation (Yoon 2006) or ..... Hench L L and West J K 1990 Principles of electronic ceramics. (New York: Wiley).

  12. Effect of temperature and time on solvothermal synthesis of ...

    Indian Academy of Sciences (India)

    School of Chemical and Materials Engineering, National University of Science and Technology, H/12 Islamabad, Pakistan; Austrian Institute of Technology GmbH, Advanced Materials & Aerospace Technologies, A-2444 Seibersdorf, Austria; Centre of Electrochemical Surface Technology, A-2700 Wiener Neustadt, Austria ...

  13. Solvothermal growth of single-crystal CdS nanowires

    Indian Academy of Sciences (India)

    Home; Journals; Bulletin of Materials Science; Volume 37; Issue 2. Solvothermal ... Ng Z Hassan. Electronic Supplementary Material Volume 37 Issue 2 April 2014 pp 337-345 ... The optical absorption of the grown NWs shows a sharp absorption edge with a blueshift, which indicates an expansion of the optical band gap.

  14. Programming Entity Framework

    CERN Document Server

    Lerman, Julia

    2009-01-01

    Programming Entity Framework is a thorough introduction to Microsoft's new core framework for modeling and interacting with data in .NET applications. This highly-acclaimed book not only gives experienced developers a hands-on tour of the Entity Framework and explains its use in a variety of applications, it also provides a deep understanding of its architecture and APIs -- knowledge that will be extremely valuable as you shift to the Entity Framework version in .NET Framework 4.0 and Visual Studio 2010. From the Entity Data Model (EDM) and Object Services to EntityClient and the Metadata Work

  15. Porous microspheres of manganese-cerium mixed oxides by a polyvinylpyrrolidone assisted solvothermal method

    Science.gov (United States)

    Schmit, F.; Bois, L.; Chiriac, R.; Toche, F.; Chassagneux, F.; Descorme, C.; Besson, M.; Khrouz, L.

    2017-04-01

    Mixed cerium manganese oxides were synthesized using a polyvinylpyrrolidone (PVP) assisted solvothermal method. Materials obtained after calcination at 400 °C were characterized by X-ray diffraction, scanning and transmission electron microscopies, electron paramagnetic resonance (EPR), Raman spectroscopy, thermal analysis and nitrogen adsorption/desorption isotherms. The influence of the synthesis parameters on the oxide structure, such as the Mn:Ce ratio or the amount of PVP, was discussed. Micrometric spheres of mixed Mn-Ce oxides, resulting from the aggregation of 100 nm porous snowflakes, were successfully synthesized. These snowflakes were formed from the aggregation of smaller oriented crystallites (size 4 nm). The hydrothermal stability of these materials was also investigated.

  16. Solvothermally Synthesized Sb2Te3 Platelets Show Unexpected Optical Contrasts in Mid-Infrared Near-Field Scanning Microscopy.

    Science.gov (United States)

    Hauer, Benedikt; Saltzmann, Tobias; Simon, Ulrich; Taubner, Thomas

    2015-05-13

    We report nanoscale-resolved optical investigations on the local material properties of Sb2Te3 hexagonal platelets grown by solvothermal synthesis. Using mid-infrared near-field microscopy, we find a highly symmetric pattern, which is correlated to a growth spiral and which extends over the entire platelet. As the origin of the optical contrast, we identify domains with different densities of charge carriers. On Sb2Te3 samples grown by other means, we did not find a comparable domain structure.

  17. Utilization of solvothermally grown InP/ZnS quantum dots as wavelength converters for fabrication of white light-emitting diodes.

    Science.gov (United States)

    Jang, Eun-Pyo; Yang, Heesun

    2013-09-01

    This work reports on a simple solvothermal synthesis of InP/ZnS core/shell quantum dots (QDs) using a much safer and cheaper phosphorus precursor of tris(dimethylamino)phosphine than the most popularly chosen tris(trimethylsilyl)phosphine. The band gap of InP QDs is facilely controlled by varying the solvothermal core growth time (4 vs. 6 h) with a fixed temperature of 150 degrees C, and the successive solvothermal ZnS shelling at 220 degrees C for 6 h results in green- and yellow-emtting InP/ZnS QD with emission quantum yield of 41-42%. The broad size distribution of as-synthesized InP/ZnS QDs, which appears to be inherent in the current solvothermal approach, is improved by a size-selective sorting procedure, and the emission properties of the resulting size-sorted QD fractions are investigated. To produce white emission for general lighting source, a blue light-emitting diode (LED) is combined with non-size-soroted green or yellow QDs as wavelength converters. Furthermore, the QD-LED that includes a blend of green and yellow QDs is fabricated to generate a white lighting source with an enhanced color rendering performance, and its electroluminescent properties are characterized in detail.

  18. Programming Drupal 7 entities

    CERN Document Server

    Michael, Sammy

    2013-01-01

    The book follows a standard tutorial-based approach to create, retrieve, update, and delete Drupal 7 entities, their properties and fields.Programming Drupal 7 Entities is perfect for intermediate or advanced developers new to Drupal entity development who are looking to get a good grounding in how to code using the new paradigm. It's assumed that you will have some experience in PHP development already, and being vaguely familiar with Drupal, GIT, and Drush will also help.

  19. Moving Hands, Moving Entities

    Science.gov (United States)

    Setti, Annalisa; Borghi, Anna M.; Tessari, Alessia

    2009-01-01

    In this study we investigated with a priming paradigm whether uni and bimanual actions presented as primes differently affected language processing. Animals' (self-moving entities) and plants' (not self-moving entities) names were used as targets. As prime we used grasping hands, presented both as static images and videos. The results showed an…

  20. Completing lists of entities

    NARCIS (Netherlands)

    Fissaha Adafre, S.; de Rijke, M.; Tjong Kim Sang, E.

    2009-01-01

    We consider the list completion task, an entity retrieval task where, in return to a topic statement and a number of example entities, systems have to return further examples. For this task, we propose and evaluate several algorithms. One of the core challenges is to overcome the very limited amount

  1. Programming Entity Framework

    CERN Document Server

    Lerman, Julia

    2010-01-01

    Get a thorough introduction to ADO.NET Entity Framework 4 -- Microsoft's core framework for modeling and interacting with data in .NET applications. The second edition of this acclaimed guide provides a hands-on tour of the framework latest version in Visual Studio 2010 and .NET Framework 4. Not only will you learn how to use EF4 in a variety of applications, you'll also gain a deep understanding of its architecture and APIs. Written by Julia Lerman, the leading independent authority on the framework, Programming Entity Framework covers it all -- from the Entity Data Model and Object Service

  2. Solvothermal synthesis and spectroscopic characterization of three lanthanide complexes with high luminescent properties [H2NMe2]3[Ln(III)(2,6-pyridinedicarboxylate)3] (Ln = Sm, Eu, Tb): In the presence of 4,4‧-Bipyridyl

    Science.gov (United States)

    Viveros-Andrade, Alan G.; Colorado-Peralta, Raúl; Flores-Alamo, Marcos; Castillo-Blum, Silvia E.; Durán-Hernández, Jesús; Rivera, José María

    2017-10-01

    Three lanthanide complexes, [H2NMe2]3[Ln(III)(2,6-pyridinedicarboxylate)3] (Ln = Sm, Eu, Tb) have been successfully synthesized using a solvothermal method in the presence of a base and they were prepared from inexpensive and readily available reactants. Infrared, ultraviolet-visible absorption spectroscopies, elemental analyses and thermogravimetric analysis were employed for the characterization. Crystals suitable for X-ray diffraction were isolated in good yields by a simple filtration, their crystal structures were analyzed; the samarium structure has orthorhombic symmetry with space group Pbcn, exhibiting three-dimensional supramolecular architecture through hydrogen bonding interactions. The metal center is coordinated to nine atoms corresponding to three pyridine-2,6-dicarboxylic acid molecules. These compounds are thermally stable up to 270 °C.

  3. Named Entity Linking Algorithm

    Directory of Open Access Journals (Sweden)

    M. F. Panteleev

    2017-01-01

    Full Text Available In the tasks of processing text in natural language, Named Entity Linking (NEL represents the task to define and link some entity, which is found in the text, with some entity in the knowledge base (for example, Dbpedia. Currently, there is a diversity of approaches to solve this problem, but two main classes can be identified: graph-based approaches and machine learning-based ones. Graph and Machine Learning approaches-based algorithm is proposed accordingly to the stated assumptions about the interrelations of named entities in a sentence and in general.In the case of graph-based approaches, it is necessary to solve the problem of identifying an optimal set of the related entities according to some metric that characterizes the distance between these entities in a graph built on some knowledge base. Due to limitations in processing power, to solve this task directly is impossible. Therefore, its modification is proposed. Based on the algorithms of machine learning, an independent solution cannot be built due to small volumes of training datasets relevant to NEL task. However, their use can contribute to improving the quality of the algorithm. The adaptation of the Latent Dirichlet Allocation model is proposed in order to obtain a measure of the compatibility of attributes of various entities encountered in one context.The efficiency of the proposed algorithm was experimentally tested. A test dataset was independently generated. On its basis the performance of the model was compared using the proposed algorithm with the open source product DBpedia Spotlight, which solves the NEL problem.The mockup, based on the proposed algorithm, showed a low speed as compared to DBpedia Spotlight. However, the fact that it has shown higher accuracy, stipulates the prospects for work in this direction.The main directions of development were proposed in order to increase the accuracy of the system and its productivity.

  4. Growth of dandelion-shaped CuInSe2 nanostructures by a two-step solvothermal process

    Science.gov (United States)

    Zhou, Wenwen; Yin, Zongyou; Hao Sim, Dao; Zhang, Hua; Ma, Jan; Hng, Huey Hoon; Yan, Qingyu

    2011-05-01

    CuInSe2 (CIS) nanodandelion structures were synthesized by a two-step solvothermal approach. First, InSe nanodandelions were prepared by reacting In(acac)3 with trioctylphosphine-selenide (TOP-Se) in 1-octadecene (ODE) at 170 °C in the presence of oleic acid. These InSe dandelions were composed of polycrystalline nanosheets with thickness dandelions could be tuned within the range of 300 nm-2 µm by adjusting the amount of oleic acid added during the synthesis. The InSe dandelion structures were then reacted with Cu(acac)2 in the second-step solvothermal process in ODE to form CIS nanodandelions. The band gap of the CIS dandelions was determined from ultraviolet (UV) absorption measurements to be ~ 1.36 eV, and this value did not show any obvious change upon varying the size of the CIS dandelions. Brunauer-Emmett-Teller (BET) measurements showed that the specific surface area of these CIS dandelion structures was 44.80 m2 g - 1, which was more than five times higher than that of the CIS quantum dots (e.g. 8.22 m2 g - 1) prepared by using reported protocols. A fast photoresponsive behavior was demonstrated in a photoswitching device using the 200 nm CIS dandelions as the active materials, which suggested their possible application in optoelectronic devices.

  5. Mastering entity framework

    CERN Document Server

    Singh, Rahul Rajat

    2015-01-01

    This book is for .NET developers who are developing data-driven applications using ADO.NET or other data access technologies. This book is going to give you everything you need to effectively develop and manage data-driven applications using Entity Framework.

  6. Copper-indium-gallium-diselenide nanoparticles synthesized by a solvothermal method for solar cell application

    Directory of Open Access Journals (Sweden)

    Chiou Chuan-Sheng

    2017-01-01

    Full Text Available Chalcopyrite copper-indium-gallium-diselenide (CIGS nanoparticles are useful for photovoltaic applications. In this study, the synthesis of CIGS powder was examined, and the powder was successfully synthesized using a relatively simple and convenient elemental solvothermal route. From the reactions of elemental Cu, In, Se and Ga(NO33 powders in an autoclave with ethylenediamine as a solvent, spherical CIGS nanoparticles, with diameters ranging from 20-40 nm, were obtained using a temperature of 200°C for 36h. The structure, morphology, chemical composition and optical properties of the as-synthesized CIGS were characterized using X-ray diffraction, transmission electron microscopy, selected area electron diffraction, scanning electron microscopy, inductively coupled plasma-mass spectrometry. In this sample, the mole ratio of Cu:In:Ga:Se was equal to 0.89:0.71:0.29:2.01, and the optical band gap was found to be 1.18 eV. The solar cell obtained a power conversion efficiency of 5.62% under standard air mass 1.5 global illumination.

  7. Morphology-controlled magnetite nanoclusters via polyethyleneimine-mediated solvothermal process

    Energy Technology Data Exchange (ETDEWEB)

    Chaleawlert-umpon, Saowaluk [National Nanotechnology Center, National Science and Technology Development Agency, 113 Thailand Science Park, Paholyothin Rd., Klong 1, Klong Luang, Pathumthani 12120 (Thailand); Pimpha, Nuttaporn, E-mail: Nuttaporn@nanotec.or.th [National Nanotechnology Center, National Science and Technology Development Agency, 113 Thailand Science Park, Paholyothin Rd., Klong 1, Klong Luang, Pathumthani 12120 (Thailand)

    2012-07-16

    A facile one-pot synthesis of polyethyleneimine (PEI)-functionalized magnetic nanoclusters (MNPs) through the solvothermal method was reported for various applications. The morphology of the MNPs can be systematically tuned from loose flower-like to porous nanoclusters by controlling the pH of the PEI stabilizer. At low pH, the intense electrostatic repulsion according to the large amount of protonated amine groups of PEI would play a key role on self-assembly process to generate the loose nanostructure. Due to the presence of amine functional groups on the surface, these nanoclusters provide high degree of dispersibility in water and abundant anchoring groups for further attachment of biomolecules. Magnetization study of the MNPs indicated that they had saturated magnetization upto 80 emu g{sup -1}. Highlights: Black-Right-Pointing-Pointer The morphology of PEI-coated magnetic nanoclusters can be manipulated by altering pH of PEI. Black-Right-Pointing-Pointer The plausible formation process is discussed based on the experimental results. Black-Right-Pointing-Pointer The nanoclusters can be easily manipulated by external magnetic fields. Black-Right-Pointing-Pointer The free amine groups located on the nanocluster surface allow stability and surface modification.

  8. A rapid microwave-assisted solvothermal approach to lower-valent transition metal oxides.

    Science.gov (United States)

    Moorhead-Rosenberg, Zachary; Harrison, Katharine L; Turner, Travis; Manthiram, Arumugam

    2013-11-18

    A green, rapid microwave-assisted solvothermal process using tetraethylene glycol (TEG) as a reducing agent has been explored as a soft-chemistry route for the preparation of various lower-valent transition metal oxides. To demonstrate the feasibility of the approach, lower-valent binary oxides such as V4O9, Mn3O4 or MnO, CoO, and Cu2O have been obtained within a short reaction time of 30 min by reducing, respectively, V2O5, MnO2, Co3O4, and CuO with TEG at LaCoO3, LaNiO3, and La4Ni3O10. The oxidation state of the transition metal ions and the oxygen content in these ternary oxides could be tuned by precisely controlling the reaction temperatures from 160 to 300 °C. The products have been characterized by X-ray powder diffraction and iodometric titration. The versatility of this novel technique is demonstrated by the facile synthesis of V4O9, which has only been produced recently in single-phase form.

  9. Antifungal activity of gold nanoparticles prepared by solvothermal method

    Energy Technology Data Exchange (ETDEWEB)

    Ahmad, Tokeer, E-mail: tahmad3@jmi.ac.in [Nanochemistry Laboratory, Department of Chemistry, Jamia Millia Islamia, New Delhi 110025 (India); Wani, Irshad A.; Lone, Irfan H.; Ganguly, Aparna [Nanochemistry Laboratory, Department of Chemistry, Jamia Millia Islamia, New Delhi 110025 (India); Manzoor, Nikhat; Ahmad, Aijaz [Department of Biosciences, Jamia Millia Islamia, New Delhi 110025 (India); Ahmed, Jahangeer [Department of Chemistry, Michigan State University, East Lansing, MI 48824 (United States); Al-Shihri, Ayed S. [Department of Chemistry, Faculty of Science, King Khalid University, Abha 61413, P.O. Box 9004 (Saudi Arabia)

    2013-01-15

    Graphical abstract: Gold nanoparticles (7 and 15 nm) of very high surface area (329 and 269 m{sup 2}/g) have been successfully synthesized through solvothermal method by using tin chloride and sodium borohydride as reducing agents. As-prepared gold nanoparticles shows very excellent antifungal activity against Candida isolates and activity increases with decrease in the particle size. Display Omitted Highlights: ► Effect of reducing agents on the morphology of gold nanoparticles. ► Highly uniform and monodisperse gold nanoparticles (7 nm). ► Highest surface area of gold nanoparticles (329 m{sup 2/}g). ► Excellent antifungal activity of gold nanoparticles against Candida strains. -- Abstract: Gold nanoparticles have been successfully synthesized by solvothermal method using SnCl{sub 2} and NaBH{sub 4} as reducing agents. X-ray diffraction studies show highly crystalline and monophasic nature of the gold nanoparticles with face centred cubic structure. The transmission electron microscopic studies show the formation of nearly spherical gold nanoparticles of average size of 15 nm using SnCl{sub 2}, however, NaBH{sub 4} produced highly uniform, monodispersed and spherical gold nanoparticles of average grain size of 7 nm. A high surface area of 329 m{sup 2}/g for 7 nm and 269 m{sup 2}/g for 15 nm gold nanoparticles was observed. UV–vis studies assert the excitations over the visible region due to transverse and longitudinal surface plasmon modes. The gold nanoparticles exhibit excellent size dependant antifungal activity and greater biocidal action against Candida isolates for 7 nm sized gold nanoparticles restricting the transmembrane H{sup +} efflux of the Candida species than 15 nm sized gold nanoparticles.

  10. Fabrication of white light-emitting diodes based on solvothermally synthesized copper indium sulfide quantum dots as color converters

    Science.gov (United States)

    Song, Woo-Seuk; Yang, Heesun

    2012-04-01

    A facile, large-scalable solvothermal synthesis of copper indium sulfide (CIS) quantum dots (QDs) and their application to the fabrication of QD-based white light-emitting diodes (LEDs) are reported. Depending on CIS QD growth time of 2 versus 5 h, the core/shell structured QDs of CIS/ZnS exhibit tunable emissions of yellow-orange with excellent quantum yields of 55%-91%. A white QD-LED is realized by applying CIS (2 h)/ZnS QD as a blue-to-yellow color converter. Furthermore, a white QD-LED having a blend of yellow and orange QDs is fabricated to improve a color rendering property through spectral extension, and its electroluminescent properties are evaluated.

  11. Structural and Morphological Tuning of LiCoPO4 Materials Synthesized by Solvo-Thermal Methods for Li-Cell Applications

    Directory of Open Access Journals (Sweden)

    Jessica Manzi

    2015-12-01

    Full Text Available Olivine-type lithium metal phosphates (LiMPO4 are promising cathode materials for lithium-ion batteries. LiFePO4 (LFP is commonly used in commercial Li-ion cells but the Fe3+/Fe2+ couple can be usefully substituted with Mn3+/Mn2+, Co3+/Co2+, or Ni3+/Ni2+, in order to obtain higher redox potentials. In this communication we report a systematic analysis of the synthesis condition of LiCoPO4 (LCP using a solvo-thermal route at low temperature, the latter being a valuable candidate to overcome the theoretical performances of LFP. In fact, LCP shows higher working potential (4.8 V vs. 3.6 V compared to LFP and similar theoretical capacity (167 mAh·g−1. Our goal is to show the effect of the synthesis condition of the ability of LCP to reversibly cycle lithium in electrochemical cells. LCP samples have been prepared through a solvo-thermal method in aqueous-non aqueous solvent blends. Different Co2+ salts have been used to study the effect of the anion on the crystal growth as well as the effect of solution acidity, temperature and reaction time. Materials properties have been characterized by Fast-Fourier transform infrared spectroscopy, X-ray diffraction and scanning electron microscopies. The correlation between structure/morphology and electrochemical performances has been investigated by galvanostatic charge-discharge cycles.

  12. Growth of dandelion-shaped CuInSe{sub 2} nanostructures by a two-step solvothermal process

    Energy Technology Data Exchange (ETDEWEB)

    Zhou Wenwen; Yin Zongyou; Sim, Dao Hao; Zhang Hua; Ma Jan; Hng, Huey Hoon; Yan Qingyu, E-mail: alexyan@ntu.edu.sg [School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798 (Singapore)

    2011-05-13

    CuInSe{sub 2} (CIS) nanodandelion structures were synthesized by a two-step solvothermal approach. First, InSe nanodandelions were prepared by reacting In(acac){sub 3} with trioctylphosphine-selenide (TOP-Se) in 1-octadecene (ODE) at 170 {sup 0}C in the presence of oleic acid. These InSe dandelions were composed of polycrystalline nanosheets with thickness < 10 nm. The size of the InSe dandelions could be tuned within the range of 300 nm-2 {mu}m by adjusting the amount of oleic acid added during the synthesis. The InSe dandelion structures were then reacted with Cu(acac){sub 2} in the second-step solvothermal process in ODE to form CIS nanodandelions. The band gap of the CIS dandelions was determined from ultraviolet (UV) absorption measurements to be {approx} 1.36 eV, and this value did not show any obvious change upon varying the size of the CIS dandelions. Brunauer-Emmett-Teller (BET) measurements showed that the specific surface area of these CIS dandelion structures was 44.80 m{sup 2} g{sup -1}, which was more than five times higher than that of the CIS quantum dots (e.g. 8.22 m{sup 2} g{sup -1}) prepared by using reported protocols. A fast photoresponsive behavior was demonstrated in a photoswitching device using the 200 nm CIS dandelions as the active materials, which suggested their possible application in optoelectronic devices.

  13. Effect of solvent medium on the structural, morphological and optical properties of ZnS nanoparticles synthesized by solvothermal route

    Energy Technology Data Exchange (ETDEWEB)

    Mendil, R., E-mail: radia.mendil@yahoo.fr [Laboratoire de Physique des Matériaux et des Nanomatériaux appliquée à l' Environnement, Université de Gabès, Faculté des Sciences de Gabès, Cité Erriadh Manara Zrig, 6072 Gabès (Tunisia); Ben Ayadi, Z. [Laboratoire de Physique des Matériaux et des Nanomatériaux appliquée à l' Environnement, Université de Gabès, Faculté des Sciences de Gabès, Cité Erriadh Manara Zrig, 6072 Gabès (Tunisia); Djessas, K. [Laboratoire Procédés, Matériaux et Energie Solaire (PROMES-CNRS), TECNOSUD, Rambla de la thermodynamique, 66100 Perpignan (France); Université de Perpignan Via Domitia, 52 avenue Paul Alduy, 68860, Perpignan Cedex9 (France)

    2016-09-05

    Different morphologies of ZnS have been synthesized by a facile solvothermal approach in a mixed solvent made of Ethylenediamine (EN) and distilled water. The effect of solvent medium on the structural, morphological and optical properties of ZnS nanoparticles were investigated. The formation mechanism of different morphologies was proposed based on the experiment results. The as-prepared samples were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), energy dispersive spectrometer (EDS), Raman spectroscopy and UV-Vis-IR spectrophotometer. The results show that phase transformation is easily induced and there is a strong correlation between morphology and structure of the ZnS nanocrystals by changing the solvent. The results also show that we have successfully produced hexagonal phase ZnS nanorods with mixed solvent. The grain sizes in the range of 17–22 nm were obtained according to elaboration conditions. Raman spectra show the intense peak at 346 cm{sup −1}, which is a typical Raman peak of bulk ZnS crystal, no signature of secondary phases. The band gap of ZnS increased from 3.49 to 3.74 eV with an increase in the EN composition in the solvent, implying that the optical properties of these materials are clearly affected by the synthesis medium. - Highlights: • ZnS was prepared at low temperature using solvothermal method. • The phase transformation and shape evolution processes were studied. • The role of solvent (EN/W) has been discussed for formation of ZnS nanostructures with different morphology. • The properties and growth mechanism of ZnS nanoparticles were investigated. • Optical band gap of ZnS powder were investigated using UV vis spectroscopy.

  14. A novel solvothermal route for obtaining strontium titanate nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Marquez-Herrera, A., E-mail: alfredo.marquez@uaslp.mx [Universidad Autonoma de San Luis Potosi, Departamento de Ingenieria Mecanica Administrativa, Coordinacion Academica Region Altiplano (COARA) (Mexico); Ovando-Medina, Victor M.; Corona-Rivera, Miguel A. [Universidad Autonoma de San Luis Potosi, Departamento de Ingenieria Quimica, Coordinacion Academica Region Altiplano (COARA) (Mexico); Hernandez-Rodriguez, E.; Zapata-Torres, M. [Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada, Unidad Legaria IPN (Mexico); Campos-Gonzalez, E.; Guillen-Cervantes, A.; Zelaya-Angel, O.; Melendez-Lira, M. [CINVESTAV-IPN, Departamento de Fisica (Mexico)

    2013-04-15

    Strontium titanate (SrTiO{sub 3}) has attracted a lot of attention because of its possible applications in new microelectronic devices. It is a material with a high dielectric constant, low leakage current, and some of its properties can be changed by adding or modifying the concentration of a dopant, which can be used for a wide range of functional purposes, from simple capacitors to complicated microwave devices. Therefore, in this work, we report the development of a new route to synthesize SrTiO{sub 3} nanoparticles based on the solvothermal method by employing two precursor solutions: strontium chloride and titanium(IV) butoxide. Our route allows the production of cubic SrTiO{sub 3} nanoparticles with a narrow size distribution. The particle sizes range between 8 and 24 nm, forming agglomerates of SrTiO{sub 3} in the range of 128-229 nm. It was demonstrated that the Ti/Sr molar ratio employed into the precursor solution has an important effect onto the chemical composition of the resulting SrTiO{sub 3} nanoparticles: when using Ti/Sr < 1, the formation and incorporation of the SrCO{sub 3} compound into the nanoparticles was observed while with Ti/Sr {>=} 1 nanoparticles are free of contaminants. The as-prepared nanoparticles were characterized by energy-dispersive X-ray spectroscopy, X-ray diffraction, transmission electron microscopy, high-resolution TEM, selected area electron diffraction, scanning electron microscopy, and dynamic light scattering.

  15. Solvothermal Molecular Precursor Routes to Semiconductor Film and Crystal Growth

    National Research Council Canada - National Science Library

    Gillan, Edward

    2002-01-01

    .... Reactions were run in toluene, THF, and under solvent free conditions. An in situ precursor synthesis and decomposition resulted in GaN nanoparticles from simple starting materials (GaCl(3) and NaN(3...

  16. Entity resolution for uncertain data

    NARCIS (Netherlands)

    Ayat, N.; Akbarinia, R.; Afsarmanesh, H.; Valduriez, P.

    2012-01-01

    Entity resolution (ER), also known as duplicate detection or record matching, is the problem of identifying the tuples that represent the same real world entity. In this paper, we address the problem of ER for uncertain data, which we call ERUD. We propose two different approaches for the ERUD

  17. Flowerlike vanadium sesquioxide: solvothermal preparation and electrochemical properties.

    Science.gov (United States)

    Liu, Haimei; Wang, Yonggang; Li, Huiqiao; Yang, Wensheng; Zhou, Haoshen

    2010-10-25

    A novel 3D hierarchical flowerlike vanadium sesquioxide (V(2)O(3)) nano/microarchitecture consisting of numerous nanoflakes is prepared via a solvothermal approach followed by an appropriate heating treatment. The as-obtained nanostructured V(2)O(3) flower is characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET) analysis, and transmission electron microscopy (TEM) (or/and high-resolution TEM, HRTEM), and it is found that the V(2)O(3) flower is constructed by single-crystalline nanoflakes. Furthermore, it is demonstrated that the surface of the flowerlike V(2)O(3) material is composed of nanostructured pores, which derive from the adsorption/desorption of nitrogen, and that the pore-size distribution depends on the unique three-dimensional interconnection between nanoflakes and on their intrinsic properties. The electrochemical behavior of the V(2)O(3) flower for lithium-ion insertion/extraction in non-aqueous solution as well as the faradaic capacitance for pesudocapacitors in a neutral aqueous solution are also investigated. A reversible discharge capacity as high as 325 mA h g(-1) is obtained at a current density of 0.02 A g(-1) from a LiClO(4)/EC:DEC electrolyte solution (i.e. LiClO(4) in ethyl carbonate and diethyl carbonate). When used as the cathode material of pesudocapacitors in Li(2)SO(4), the flowerlike oxide displayed a very high initial capacitance of 218 F g(-1) at a current density of 0.05 A g(-1). We believe that the good performance of the flowerlike V(2)O(3) electrode is most probably due to its unique 3D hierarchical nano/microarchitecture, which shows that the electrochemical properties of a cathodic material do not only depend on the oxidation state of that material but also-to a large extent-on its crystalline structure and morphology. The aforementioned properties suggest that the present V(2)O(3) flower materials may have a great potential to be employed as electrode materials in

  18. Service entity network virtualization architecture and model

    Science.gov (United States)

    Jin, Xue-Guang; Shou, Guo-Chu; Hu, Yi-Hong; Guo, Zhi-Gang

    2017-07-01

    Communication network can be treated as a complex network carrying a variety of services and service can be treated as a network composed of functional entities. There are growing interests in multiplex service entities where individual entity and link can be used for different services simultaneously. Entities and their relationships constitute a service entity network. In this paper, we introduced a service entity network virtualization architecture including service entity network hierarchical model, service entity network model, service implementation and deployment of service entity networks. Service entity network oriented multiplex planning model were also studied and many of these multiplex models were characterized by a significant multiplex of the links or entities in different service entity network. Service entity networks were mapped onto shared physical resources by dynamic resource allocation controller. The efficiency of the proposed architecture was illustrated in a simulation environment that allows for comparative performance evaluation. The results show that, compared to traditional networking architecture, this architecture has a better performance.

  19. From dihydrated iron(III) phosphate to monohydrated ammonium-iron(II) phosphate: Solvothermal reaction mediated by acetone-urea mixtures

    Energy Technology Data Exchange (ETDEWEB)

    Alfonso, Belen F., E-mail: mbafernandez@uniovi.es [Departamento de Fisica, Universidad de Oviedo, Calvo Sotelo, s/n 33007 Oviedo (Spain); Trobajo, Camino [Departamento de Quimica Organica e Inorganica, Universidad de Oviedo-CINN, Julian Claveria 8, 33006 Oviedo (Spain); Pique, Carmen [Departamento de Fisica, Universidad de Oviedo, Calvo Sotelo, s/n 33007 Oviedo (Spain); Garcia, Jose R. [Departamento de Quimica Organica e Inorganica, Universidad de Oviedo-CINN, Julian Claveria 8, 33006 Oviedo (Spain); Blanco, Jesus A. [Departamento de Fisica, Universidad de Oviedo, Calvo Sotelo, s/n 33007 Oviedo (Spain)

    2012-12-15

    By reaction between synthetic phosphosiderite FePO{sub 4}{center_dot}2H{sub 2}O, urea (NH{sub 2}){sub 2}CO, and acetone (CH{sub 3}){sub 2}CO, we report a novel solvothermal synthesis of polycrystalline NH{sub 4}FePO{sub 4}{center_dot}H{sub 2}O. The preparation of other two individual phases, NH{sub 4}Fe{sub 2}(OH)(PO{sub 4}){sub 2}{center_dot}2H{sub 2}O and NH{sub 4}Fe{sub 2}(PO{sub 4}){sub 2}, is also described. The obtained product is a function of the reaction time and the N/P molar ratio in the reagent mixture, and the existence of structural memory in the dissolution-precipitation processes is discussed. Below 25 K, NH{sub 4}FePO{sub 4}{center_dot}H{sub 2}O behaves magnetically in a complex way, because both ferromagnetic and antiferromagnetic signals are superimposed, suggesting the existence of a canting of iron(II) magnetic moments. - Graphical abstract: Solvothermal synthesis of polycrystalline NH{sub 4}FePO{sub 4}{center_dot}H{sub 2}O is presented. The preparation of other two individual phases, NH{sub 4}Fe{sub 2}(OH)(PO{sub 4}){sub 2}{center_dot}2H{sub 2}O and NH{sub 4}Fe{sub 2}(PO{sub 4}){sub 2} as a function of the N/P molar ratio in the reagent mixture and the reaction time, is also described. Highlights: Black-Right-Pointing-Pointer Solvothermal synthesis of NH{sub 4}FePO{sub 4}{center_dot}H{sub 2}O from an Fe(III) phosphate: reduction process. Black-Right-Pointing-Pointer Formation of two intermediate metastable phases: phase diagram. Black-Right-Pointing-Pointer Thermal decomposition in two steps: mass loss of both water and ammonia. Black-Right-Pointing-Pointer Magnetic behaviour: AF+constant spontaneous magnetization.

  20. Effect of preparation methods on the properties of titania nanoparticles: solvothermal versus sol-gel

    Science.gov (United States)

    Dastan, Davoud

    2017-11-01

    Titania (TiO2) nanoparticles (NP's) have been prepared by solvothermal and sol-gel techniques using different surfactants such as acetic acid (AA), oleylamine (OM), and AA + OM. The solution was thermally treated at growth temperature 180 °C in solvothermal method. TiO2 powder, prepared using both methods, was subjected to post heat treatment at 550 and 950 °C. The effect of surfactants on the morphology of TiO2 NP's was studied by transmission electron microscopy (TEM) and field emission scanning electron microscopy (FESEM). The structural and thermal properties of titania NP's are investigated by means of X-ray diffraction, Raman spectroscopy, thermogravimetric analysis, and differential scanning calorimetry (TGA/DSC). TEM and FESEM images illustrated various shapes of titania NP's such as irregular spherical, rounded rectangular, truncated rhombic, oval, and rod-like structure in presence of different surfactants. Moreover, TiO2 particles prepared by sol-gel method were almost 40 times greater than those prepared by solvothermal method. In addition to the improvement in the crystallinity, thermal stability has been enhanced due to consolidation of individual particles at higher annealing temperature in solvothermal technique. Furthermore, a reduction in the degradation temperature and phase transformation of TiO2 NP's were conspicuously corroborated after post-heat treatment.

  1. Removal of brominated flame retardant from electrical and electronic waste plastic by solvothermal technique

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Cong-Cong [Research Center For Eco-Environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Beijing 100085 (China); Zhang, Fu-Shen, E-mail: fszhang@rcees.ac.cn [Research Center For Eco-Environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Beijing 100085 (China)

    2012-06-30

    Highlights: Black-Right-Pointing-Pointer A process for brominated flame retardants (BFRs) removal in plastic was established. Black-Right-Pointing-Pointer The plastic became bromine-free with the structure maintained after this treatment. Black-Right-Pointing-Pointer BFRs transferred into alcohol solvent were easily debrominated by metallic copper. - Abstract: Brominated flame retardants (BFRs) in electrical and electronic (E and E) waste plastic are toxic, bioaccumulative and recalcitrant. In the present study, tetrabromobisphenol A (TBBPA) contained in this type of plastic was tentatively subjected to solvothermal treatment so as to obtain bromine-free plastic. Methanol, ethanol and isopropanol were examined as solvents for solvothermal treatment and it was found that methanol was the optimal solvent for TBBPA removal. The optimum temperature, time and liquid to solid ratio for solvothermal treatment to remove TBBPA were 90 Degree-Sign C, 2 h and 15:1, respectively. After the treatment with various alcohol solvents, it was found that TBBPA was finally transferred into the solvents and bromine in the extract was debrominated catalyzed by metallic copper. Bisphenol A and cuprous bromide were the main products after debromination. The morphology and FTIR properties of the plastic were generally unchanged after the solvothermal treatment indicating that the structure of the plastic maintained after the process. This work provides a clean and applicable process for BFRs-containing plastic disposal.

  2. Fabrication of α-Bi2O3 Microrods by Solvothermal Method and Their Photocatalytic Performance

    National Research Council Canada - National Science Library

    Wang, Jian; Liu, Jun; Wang, Bingbing; Zhu, LinLin; Hu, JieHui; Xu, Hongbo

    2014-01-01

    An ethanol–water (CH3CH2OH–H2O) system was designed to synthesize α-Bi2O3 microrods by a mild and one-step solvothermal method in the presence of surfactant dodecylamine (C12H27N). X-ray diffraction (XRD...

  3. Sterile pyuria: a forgotten entity

    OpenAIRE

    Goonewardene, Sanchia; Persad, Raj

    2015-01-01

    Sterile pyuria is a common entity. Yet there are no guidelines to address this issue. We have conducted a systematic review over 20 years and reviewed the results. Guidelines for assessment, diagnosis and management are developed based on these results.

  4. Sterile pyuria: a forgotten entity.

    Science.gov (United States)

    Goonewardene, Sanchia; Persad, Raj

    2015-10-01

    Sterile pyuria is a common entity. Yet there are no guidelines to address this issue. We have conducted a systematic review over 20 years and reviewed the results. Guidelines for assessment, diagnosis and management are developed based on these results.

  5. Named Entity Recognition for IDEAL

    OpenAIRE

    Du, Qianzhou; Zhang, Xuan

    2015-01-01

    This project explored how to apply Named Entity Recognition to large Twitter and web page datasets to extract useful entities such as people, organization, location, and date. In addition, this NER utility has been scaled to the MapReduce framework on the Hadoop cluster. A schema and software allow this to be integrated with IDEAL. The term “Named Entity”, which was first introduced by Grishman and Sundheim, is widely used in Natural Language Processing (NLP). The researchers were focusing...

  6. Hydro- and solvothermally-prepared ZnO and its catalytic effect on photodegradation of reactive orange 16 dye

    Directory of Open Access Journals (Sweden)

    Simović Bojana

    2014-01-01

    Full Text Available In this work, zinc oxide powders were obtained by two different techniques: hydro- and solvothermal synthesis starting from Zn(NO32 and Zn(CH3COO2, respectively. The influence of synthetic procedure on the structural, microstructural, thermal and photocatalytic properties of the prepared ZnO powders was investigated. Both ZnO samples were further annealed at moderate conditions (300°C to avoid grain growth and to remove traces of impurities. In all four cases a single-phase hexagonal ZnO was confirmed by X-ray powder diffraction. The morphology of prepared ZnO powders was different and it varied from rounded nanograins to microrods. All prepared samples showed higher photocatalytic efficiency in degradation of textile azo-dye Reactive Orange 16(RO16 than the commercial ZnO. In addition, the non-annealed samples had better photocatalytic properties than the commercial Degussa P25 TiO2 powder. [Projekat Ministarstva nauke Republike Srbije, br. III45007, br. ON171032 i br. ON172013

  7. Investigation on development of advanced materials by solvothermal technique; Sorubo thermal hanno riyo senshin zairyo kaihatsu ni kansuru chosa

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-03-01

    Solvothermal reaction is reaction under high temperature and high pressure, which is expected to fabricate new functional materials. In this study, the materials are classified into two fields, i.e., inorganic materials, metals and their composites and organic materials and their composites. The current status of R and D of production and processing technology in each field is surveyed and the prospect of it is discussed. For the inorganic materials, metals and their composites, it is explained that very fine metal oxide particles, complex oxides, single crystals, whiskers, compounds with layer structure, metastable compounds, ion conductors and catalysts with high ability could be produced only by controlling the solvothermal reactions in atomic order. For the organic materials and their composites, surveyed results of the solvothermal technique using non-aqueous solutions are mainly provided. The necessity of a national project for researches on the solvothermal reactions is proposed from the viewpoint of resource, environment and energy. 777 refs., 38 figs., 26 tabs.

  8. Synthesis and optical characteristics of ZnO nanocrystals

    Indian Academy of Sciences (India)

    Administrator

    (Johnson et al 2001; Zhang et al 2002). Compared to other semiconductors, ZnO has wide bandgap of 3⋅37 eV and other large excitation binding energy, which makes excitation stable even at room temperature. There are various methods in order to synthesize ZnO nanomaterials viz. solvothermal synthesis, sol–gel (Li ...

  9. Programming Entity Framework Code First

    CERN Document Server

    Lerman, Julia

    2011-01-01

    Take advantage of the Code First data modeling approach in ADO.NET Entity Framework, and learn how to build and configure a model based on existing classes in your business domain. With this concise book, you'll work hands-on with examples to learn how Code First can create an in-memory model and database by default, and how you can exert more control over the model through further configuration. Code First provides an alternative to the database first and model first approaches to the Entity Data Model. Learn the benefits of defining your model with code, whether you're working with an exis

  10. Named entity normalization in user generated content

    NARCIS (Netherlands)

    Jijkoun, V.; Khalid, M.A.; Marx, M.; de Rijke, M.

    2008-01-01

    Named entity recognition is important for semantically oriented retrieval tasks, such as question answering, entity retrieval, biomedical retrieval, trend detection, and event and entity tracking. In many of these tasks it is important to be able to accurately normalize the recognized entities,

  11. Entity ranking using Wikipedia as a pivot

    NARCIS (Netherlands)

    Kaptein, R.; Serdyukov, P.; de Vries, A.; Kamps, J.; Huang, X.J.; Jones, G.; Koudas, N.; Wu, X.; Collins-Thompson, K.

    2010-01-01

    In this paper we investigate the task of Entity Ranking on the Web. Searchers looking for entities are arguably better served by presenting a ranked list of entities directly, rather than a list of web pages with relevant but also potentially redundant information about these entities. Since

  12. A Calculus of Located Entities

    Directory of Open Access Journals (Sweden)

    Adriana Compagnoni

    2014-03-01

    Full Text Available We define BioScapeL, a stochastic pi-calculus in 3D-space. A novel aspect of BioScapeL is that entities have programmable locations. The programmer can specify a particular location where to place an entity, or a location relative to the current location of the entity. The motivation for the extension comes from the need to describe the evolution of populations of biochemical species in space, while keeping a sufficiently high level description, so that phenomena like diffusion, collision, and confinement can remain part of the semantics of the calculus. Combined with the random diffusion movement inherited from BioScape, programmable locations allow us to capture the assemblies of configurations of polymers, oligomers, and complexes such as microtubules or actin filaments. Further new aspects of BioScapeL include random translation and scaling. Random translation is instrumental in describing the location of new entities relative to the old ones. For example, when a cell secretes a hydronium ion, the ion should be placed at a given distance from the originating cell, but in a random direction. Additionally, scaling allows us to capture at a high level events such as division and growth; for example, daughter cells after mitosis have half the size of the mother cell.

  13. SOCIAL EFFECTIVENESS OF BUSINESS ENTITIES

    Directory of Open Access Journals (Sweden)

    Iryna Perevozova

    2016-06-01

    Full Text Available The article is aimed at investigation of social effectiveness of business entities. Social aspect of business is becoming a necessary component of success, increase of profitability and competitiveness as well as minimization of risks. Social effectiveness is referred to as correspondence between economic activity and main social needs and aims of society, interests of the staff and interests of a certain person. Investigation of social effectiveness of business entities is suggested to analyze with the help of social factors. Social factors are characterized by variability of expectations, relations and interests of society, staff and individuals. We suggest generalized classification of factors which have an impact on social effectiveness of business, we single out external and internal factors. To external factors belong: income of the population, differentiation of population according to income, migration, level of salaries, level of legality of income of population, family status of  population, employment rate, age structure of population etc. As for internal factors we single out the following: low level of basic professional training, use of unskilled workers, absence of conditions for creativity, imperfection of system of motivation of professional growth, absence of specialized centers for certification training etc. Quantity and quality analysis of the above mentioned factors will enable to determine the level of social effectiveness of business entities. For analyses of degree of influence of factors on effectiveness we worked out a questionnaire of expert assessment which is represented in the form of assessment scale. We conducted a questionnaire and analyzed expert results and determined degree of influence of factors on social effectiveness of business. Assessment of level of social effectiveness of business entities was carried out by expert method of certain factor and was represented by a formula. The scale of assessment of

  14. Two types of lanthanide selenidostannates(IV) first prepared under the same solvothermal conditions.

    Science.gov (United States)

    Zhou, Jian; Xiao, Hong; Xiao, Hong-Ping; Yang, Tao; Zou, Hua-Hong; Liu, Xing; Zhao, Rong-Qing; Tang, Qiuling

    2015-01-21

    Two types of lanthanide selenidostannates(iv) [Ln2(tepa)2(μ-OH)2Sn2Se6] {Ln = Y(), Pr (), Dy (), Er (), Tm (); tepa = tetraethylenepentamine} and [Ln2(tepa)2(μ2-OH)2Cl2]2[Sn4Se10]·4H2O {Ln = Y (), Dy (), Er (), Tm ()} have been synthesized under identical solvothermal conditions and characterized structurally. Type I (, , , and ) displays 1-D neutral chains [Ln2(tepa)2(μ-OH)2Sn2Se6]n, while type II (, , and ) contains discrete adamantane-like [Sn4Se10](4-) ions with binuclear lanthanide complex [Ln2(tepa)2(μ-OH)2Cl2](2+) ions as counterions. Although the solvothermal synthetic methods could result in the formation of various transition-metal chalcogenidometalates, such identical experimental conditions usually result in the only stable phases of lanthanide chalcogenidometalates. Hence, two different lanthanide selenidostannates(iv), obtained under same solvothermal conditions and starting materials, have been first observed in this work. The optical properties of all the compounds have been investigated by UV-vis spectra.

  15. A Comparative Study of Solvothermal and Sol-Gel-Derived Nanocrystalline Alumina Catalysts for Ethanol Dehydration

    Directory of Open Access Journals (Sweden)

    Mingkwan Wannaborworn

    2015-01-01

    Full Text Available The ethanol dehydration to ethylene over alumina catalysts prepared by solvothermal and sol-gel methods was investigated. Also, a commercial alumina was used for comparison purposes. The results showed that the catalytic activity depends on the properties of catalyst derived from different preparation methods and reaction temperature. The alumina synthesized by solvothermal method exhibited the highest activity. This can be attributed to the higher surface area and larger amount of acid site, especially the ratio of weak/strong acid strength as determined by N2 physisorption and NH3-TPD studies. The solvothermal-derived catalyst exhibited an excellent performance with complete ethanol conversion and 100% selectivity to ethylene at 350°C in comparison with other ones. In addition, we further studied the catalytic dehydration of alumina catalyst modified with Fe. The presence of 10 wt.% Fe decreased both conversion and ethylene selectivity. However, the acetaldehyde selectivity apparently increased. It was related to the dehydrogenation pathway that takes place on Fe species.

  16. Solvothermal and electrochemical synthetic method of HKUST-1 and its methane storage capacity

    Science.gov (United States)

    Wahyu Lestari, Witri; Adreane, Marisa; Purnawan, Candra; Fansuri, Hamzah; Widiastuti, Nurul; Budi Rahardjo, Sentot

    2016-02-01

    A comparison synthetic strategy of Metal-Organic Frameworks, namely, Hongkong University of Techhnology-1 {HKUST-1[Cu3(BTC)]2} (BTC = 1,3,5-benzene-tri-carboxylate) through solvothermal and electrochemical method in ethanol:water (1:1) has been conducted. The obtained material was analyzed using powder X-ray diffraction, Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR), Thermo-Gravimetric Analysis (TGA) and Surface Area Analysis (SAA). While the voltage in the electrochemical method are varied, ranging from 12 to 15 Volt. The results show that at 15 V the texture of the material has the best degree of crystallinity and comparable with solvothermal product. This indicated from XRD data and supported by the SEM image to view the morphology. The thermal stability of the synthesized compounds is up to 320 °C. The shape of the nitrogen sorption isotherm of the compound corresponds to type I of the IUPAC adsorption isotherm classification for microporous materials with BET surface area of 629.2 and 324.3 m2/g (for solvothermal and electrochemical product respectively) and promising for gas storage application. Herein, the methane storage capacities of these compounds are also tested.

  17. Preparation and characterization of CuInSe{sub 2} nanoparticles elaborated by novel solvothermal protocol using DMF as a solvent

    Energy Technology Data Exchange (ETDEWEB)

    Ben Marai, A., E-mail: Achraf.Benmarai@promes.cnrs.fr [Laboratoire Procédés, Matériaux et Energie Solaire, PROMES-CNRS, Tecnosud, Rambla de la thermodynamique, 66100 Perpignan (France); Laboratoire de Physique des Matériaux et des Nanomatériaux appliquée à l' Environnement, LaPhyMNE, Université de Gabès, Faculté des Sciences de Gabès, Cité Erriadh Manara Zrig, 6072 Gabès (Tunisia); Djessas, K. [Laboratoire Procédés, Matériaux et Energie Solaire, PROMES-CNRS, Tecnosud, Rambla de la thermodynamique, 66100 Perpignan (France); Université de Perpignan, Via Domitia, 52 Avenue Paul Alduy, 68860, Perpignan Cedex9 (France); Ben Ayadi, Z.; Alaya, S. [Laboratoire de Physique des Matériaux et des Nanomatériaux appliquée à l' Environnement, LaPhyMNE, Université de Gabès, Faculté des Sciences de Gabès, Cité Erriadh Manara Zrig, 6072 Gabès (Tunisia)

    2015-11-05

    In this study, high purity and near stoichiometric CuInSe{sub 2} (CIS) nanoparticles have been successfully synthesized using solvothermal route. The goal of this paper is to improve the crystal quality while reducing production cost and limiting the toxicity of solvothermal reaction, as compared to processes including selenization step. Therefore, the starting solution solvothermal is constituted by the following precursors (CuSO{sub 4}.5H{sub 2}O, InCl{sub 3}.xH{sub 2}O and Se powder) which were dissolved in N, N Dimethylformamide (DMF) as solvent. A reasonable possible mechanism for the growth of CIS nanoparticles is proposed. The effect of process parameters on the synthesis and characterization of CIS nanoparticles were examined including reaction temperature (165–240 °C), process time (12–24 h) and the drying route. The as-obtained CIS nanoparticles are analyzed using diverse techniques such as x-ray diffraction (XRD), energy dispersive spectrometer (EDS), transmission electron microscopy (TEM), Raman spectroscopy and UV–vis-IR spectrophotometer. All results demonstrate that the optimal conditions for preparing a single-phase CIS obtained at 220 °C for 24 h and followed by annealing at 400 °C for 30 min under a nitrogen atmosphere. In addition, XRD results showed that the CIS nanoparticles crystallize in the chalcopyrite structure, with grain size in the order of 25 nm, which is also confirmed by TEM images. Raman spectra show the intense peak at 171 cm{sup −1}, which correspond to the chalcopyrite structure, no signature of secondary phases. Optical measurements revealed strong absorption in the entire visible light to near-infrared region and band gap (≈1.04 eV) is very close to those of absorbent materials in thin film solar cells. - Highlights: • Highly dispersed chalcopyrite CuInSe{sub 2} nanoparticles were successfully synthesized. • The DMF solvent act as both the solvent and the complexing agent. • Band gap was calculated to be 1

  18. HMM based Korean Named Entity Recognition

    Directory of Open Access Journals (Sweden)

    Yi-Gyu Hwang

    2003-02-01

    Full Text Available In this paper, we present a named entity recognition model for Korean Language. Named entity recognition is an essential and important process of Question Answering and Information Extraction system. This paper proposes a HMM based named entity recognition using compound word construction principles. In Korean, above 60% of NE (Named-Entity is a compound word. This compound word may be consisted of proper noun, common noun, or bound noun, etc. There is an intercontextual relationship among nouns which consists NE. NE and surrounding words of NE have a contextual relationship. For considering these relationships, we classified nouns into 4 word classes (Independent Entity, Constituent Entity, Adjacent Entity, Not an Entity. With this classification, our system gets contextual and lexical information by stochastic based machine leaning method from a NE labeled training data. Experimental result shows that this approach is better approach than rulebased in the Korean named-entity recognition.

  19. Diazonium salt-mediated synthesis of new amino, hydroxy, propargyl, and maleinimido-containing superparamagnetic Fe@C nanoparticles as platforms for linking bio-entities or organocatalytic moieties

    Energy Technology Data Exchange (ETDEWEB)

    Bunge, Alexander; Magerusan, Lidia [National Institute of Research and Development for Isotopic and Molecular Technologies (Romania); Morjan, Ion [National Institute for Lasers, Plasma and Radiation Physics (Romania); Turcu, Rodica; Borodi, Gheorghe; Liebscher, Jürgen, E-mail: liebscher@chemie.hu-berlin.de [National Institute of Research and Development for Isotopic and Molecular Technologies (Romania)

    2015-09-15

    New magnetic Fe@C nanoparticles in the size range of about 20–50 nm functionalized with amino, hydroxy, propargyl, or maleinimido groups were synthesized by reaction with aryl diazonium salts. Aryl diazonium salts wherein the functional groups are linked via a sulfonamide moiety turned out to be advantageous over those with direct linkage. The obtained Fe@C nanoparticles represent magnetic nanoplatforms for linking bio-entities and organocatalysts using amide formation, CuAAC, or thiol-ene click chemistry as exemplified by selected examples. The Fe@C nanoparticles obtained exhibit supramolecular behavior with high value of saturation magnetization rendering them attractive for practical applications in biomedicine and organocatalysis.

  20. Solvothermal synthesis and characterization of acicular α-Fe2O3 ...

    Indian Academy of Sciences (India)

    Administrator

    –DTA was obtained ... The equation uses the reference peak width at angle θ, where λ is the X-ray wavelength (1⋅5418 Å) and ... Shake up satellite ~ 8 eV above the Fe 2p1/2 and Fe 2p3/2 peaks are visible. Separation of the 2p doublet is ...

  1. SCOPE OF VARIOUS SOLVENTS AND THEIR EFFECTS ON SOLVOTHERMAL SYNTHESIS OF Ni-BTC

    Directory of Open Access Journals (Sweden)

    Farrukh Israr

    2016-07-01

    Full Text Available Ni-BTC (BTC = 1,3,5-benzene tricarboxylate metal organic framework (MOF was synthesized using different solvent conditions. Solvent mixtures of water/N,N-dimethylformamide (DMF, water/ethanol, and water/ethanol/DMF were used for the reactions with or without a variety of bases at 160 ºC for 48 hours. Even with same green crystals, prepared MOFs show all different BET surface areas and different XRD patterns. The highest BET surface area of the crystals was 850 m2/g obtained from water/DMF solvent with NH4OH as a base. The measured surface areas of the crystals follows the order of Ni-BTC(water/DMF-NH4OH > Ni-BTC(water/DMF-TMA > Ni-BTC(water/DMF > Ni-BTC(water/DMF-Pyridine> Ni-BTC(water/ethanol> Ni-BTC(water/DMF-aniline> Ni-BTC(water/DMF-NaOH.

  2. Solvothermal synthesis and properties control of doped ZnO nanoparticles.

    Science.gov (United States)

    Cimitan, Samanta; Albonetti, Stefania; Forni, Laura; Peri, Francesca; Lazzari, Dario

    2009-01-01

    Indium and gallium doped ZnO nanoparticles have been prepared by a hydrothermal reaction in ethanol and methoxyethanol. A comprehensive study of the preparation process, including a thorough investigation by TG-FTIR and TG-MS of the thermal-purification procedure, is presented. Moreover, the effect of thermal conditions and dopant concentration on the structural and optical properties is discussed on the basis of XRD, TEM and UV-vis-NIR results. Reported data indicated that the use of methoxyethanol as a solvent allows an enhanced control of nanoparticle size and favours dopant incorporation into zinc oxide. Near infrared absorption of these materials can be strongly affected by increasing the doping level and upon treating nanoparticles under reducing atmosphere. Preliminary study indicated that this effect is greatly enhanced for gallium-doped zinc oxide.

  3. Solvothermal synthesis and characterization of acicular α-Fe2O3 ...

    Indian Academy of Sciences (India)

    Materials Chemistry Laboratory, Department of Materials Science, Gulbarga University, Gulbarga 585 106, India; Veeco-India Nanotechnology Laboratory, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bangalore 560 064, India; H.K.E.S. College of Pharmacy, Sedam Road, Gulbarga 585 101, India ...

  4. Compulsive buying: an overlooked entity.

    Science.gov (United States)

    Basu, Bishnupriya; Basu, Saikat; Basu, Jharna

    2011-08-01

    Compulsive buying is an under-recognised entity among Indian psychiatrists. A Medline search, hand searching of journals and direct communications with lead investigators in compulsive buying have generated numerous studies. Overseas data indicate a community prevalence between 1% and 8% . The phenomenon can be an independent entity or appears as a comorbidity with another axis I or axis II disorder. A degree of suspicion on part of clinician regarding its possible presence is the key to its detection. A few rating instruments are available to quantify the morbidity and screening for compulsive buying. Management involves pharmacotherapy with SSRIs, psychotherapy, self-help groups and self-help books. Epidemiological and clinical studies on compulsive buying should be undertaken by Indian psychiatrists to provide better services for people suffering from compulsive buying.

  5. Categorizing entities by common role.

    Science.gov (United States)

    Goldwater, Micah B; Markman, Arthur B

    2011-04-01

    Many categories group together entities that play a common role across situations. For example, guest and host refer to complementary roles in visiting situations and, thus, are role-governed categories (A. B. Markman & Stilwell, Journal of Experiment & Theoretical Artificial Intelligence, 13, 329-358, 2001). However, categorizing an entity by role is one of many possible classification strategies. This article examines factors that promote role-governed categorization over thematic-relation-based categorization (Lin & Murphy, Journal of Experimental Psychology: General, 130, 3-28, 2001). In Experiments 1a and 1b, we demonstrate that the use of novel category labels facilitates role-governed categorization. In Experiments 2a and 2b, we demonstrate that analogical comparison facilitates role-governed categorization. In Experiments 1b and 2b, we show that these facilitatory factors induce a general sensitivity to role information, as opposed to only promoting role-governed categorization on an item-by-item basis.

  6. Entity Framework 41 Expert's Cookbook

    CERN Document Server

    Liles, Devlin

    2012-01-01

    This book takes a step-by-step problem solving approach that leads you through a problem and explains each step in detail to accomplish the goal. This books gives you concrete code examples as well as detailed information on the decisions involved. This book is for intermediate to advanced .NET developers who have used LINQ to SQL or Entity Framework in some form but want to have more control over the implementation.

  7. Unprecedented connection mode of [V{sub 16}Sb{sub 4}O{sub 42}(H{sub 2}O)]{sup 8-} cluster anions by Mn{sup 2+} centered complexes. Solvothermal synthesis and properties of {[Mn(teta)]_4V_1_6Sb_4O_4_2(H_2O)}{sub n}.[(H{sub 2}O){sub 12}]{sub n}

    Energy Technology Data Exchange (ETDEWEB)

    Rasmussen, Maren; Naether, Christian; Bensch, Wolfgang [Institute of Inorganic Chemistry, Christian-Albrechts-University of Kiel (Germany); Leusen, Jan van; Koegerler, Paul [Institute of Inorganic Chemistry, RWTH Aachen University, Aachen (Germany)

    2017-11-17

    The new compound {[Mn(teta)]_4V_1_6Sb_4O_4_2}{sub n}.[(H{sub 2}O){sub 12}]{sub n} (teta = triethylenetetraamine) was synthesized under solvothermal conditions. The crystal structure features the high nuclearity [V{sub 16}{sup IV}Sb{sub 4}{sup III}O{sub 42}(H{sub 2}O)]{sup 8-} cluster anion, which consists of two rings composed of 8 edge-sharing VO{sub 5} polyhedra. The rings are perpendicular to each other generating four niches, which are occupied by two VO{sub 5} pyramids and two handle-like Sb{sub 2}O{sub 5} units. The two unique anions are each surrounded by eight Mn{sup 2+} centered complexes via Mn-O{sub term}-V bonds. Such an expansion has never been observed in heterometal polyoxovanadate chemistry. The connection mode between cluster anions and complex cations generates two individual layers stacked onto each other. Between the layers weak Sb..O contacts are observed. The crystal water molecules are mainly located in the empty space between the layers. Upon heating H{sub 2}O molecules are removed, while the crystal structure remains intact. The magnetic behavior is dominated by strong antiferromagnetic exchange interactions between the central V{sup 4+} ions, while the interaction between the cluster anion and central Mn{sup 2+} ions is significantly less pronounced. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  8. Relatedness-based Multi-Entity Summarization.

    Science.gov (United States)

    Gunaratna, Kalpa; Yazdavar, Amir Hossein; Thirunarayan, Krishnaprasad; Sheth, Amit; Cheng, Gong

    2017-08-01

    Representing world knowledge in a machine processable format is important as entities and their descriptions have fueled tremendous growth in knowledge-rich information processing platforms, services, and systems. Prominent applications of knowledge graphs include search engines (e.g., Google Search and Microsoft Bing), email clients (e.g., Gmail), and intelligent personal assistants (e.g., Google Now, Amazon Echo, and Apple's Siri). In this paper, we present an approach that can summarize facts about a collection of entities by analyzing their relatedness in preference to summarizing each entity in isolation. Specifically, we generate informative entity summaries by selecting: (i) inter-entity facts that are similar and (ii) intra-entity facts that are important and diverse. We employ a constrained knapsack problem solving approach to efficiently compute entity summaries. We perform both qualitative and quantitative experiments and demonstrate that our approach yields promising results compared to two other stand-alone state-of-the-art entity summarization approaches.

  9. Qualified Entity Certification Program for Medicare Data

    Data.gov (United States)

    U.S. Department of Health & Human Services — QECP welcomes any entities that would like to participate in, learn more about, or assess their capability to function as a qualified entity (QE) under section 10332...

  10. Neural Reranking for Named Entity Recognition

    OpenAIRE

    Yang, Jie; Zhang, Yue; Dong, Fei

    2017-01-01

    We propose a neural reranking system for named entity recognition (NER). The basic idea is to leverage recurrent neural network models to learn sentence-level patterns that involve named entity mentions. In particular, given an output sentence produced by a baseline NER model, we replace all entity mentions, such as \\textit{Barack Obama}, into their entity types, such as \\textit{PER}. The resulting sentence patterns contain direct output information, yet is less sparse without specific named ...

  11. Fine-grained Dutch named entity recognition

    OpenAIRE

    Desmet, Bart; Hoste, Veronique

    2014-01-01

    This paper describes the creation of a fine-grained named entity annotation scheme and corpus for Dutch, and experiments on automatic main type and subtype named entity recognition. We give an overview of existing named entity annotation schemes, and motivate our own, which describes six main types (persons, organizations, locations, products, events and miscellaneous named entities) and finer-grained information on subtypes and metonymic usage. This was applied to a one-million-word subset o...

  12. Chemical solution synthesis and properties of nanoscale ferroelectrics, single phase and composite multiferroics

    OpenAIRE

    Hardy, An; Van Bael, Marlies K.

    2015-01-01

    Chemical solution syntheses are frequently used for the synthesis of many kinds of metal oxides. The cited advantages include the compositional flexibility, high phase purity at relatively low temperatures, low equipment and operation cost and for some cases, the compatibility with roll-to-roll processing. Here, we focus on solution based synthesis of nanoscale BaTiO3 besides multiferroics. First, the size limit for tetragonal BaTiO3 particles from solvothermal synthesis is investigated...

  13. Entity Ranking using Wikipedia as a Pivot

    NARCIS (Netherlands)

    R. Kaptein; P. Serdyukov; A.P. de Vries (Arjen); J. Kamps

    2010-01-01

    htmlabstractIn this paper we investigate the task of Entity Ranking on the Web. Searchers looking for entities are arguably better served by presenting a ranked list of entities directly, rather than a list of web pages with relevant but also potentially redundant information about

  14. Ranking related entities: components and analyses

    NARCIS (Netherlands)

    Bron, M.; Balog, K.; de Rijke, M.

    2010-01-01

    Related entity finding is the task of returning a ranked list of homepages of relevant entities of a specified type that need to engage in a given relationship with a given source entity. We propose a framework for addressing this task and perform a detailed analysis of four core components;

  15. 77 FR 56571 - Unincorporated Business Entities

    Science.gov (United States)

    2012-09-13

    ... business entities (UBEs) organized under State law for certain business activities. For purposes of this... business entities, such as unincorporated business trusts, organized under State law. This rule does not... unincorporated business entities that are formally established and maintained through applicable State law, such...

  16. Painful constipation: a neglected entity?

    Directory of Open Access Journals (Sweden)

    G. Bassotti

    2011-01-01

    Full Text Available Functional chronic constipation is a common symptom in daily clinical practice. Although the definition of constipation may be variable, there is usually agreement that (at least for research purposes the definition given by the Rome Committee are useful. However, some blind spots or hidden angles remain, even in the more thorough classifications; among these, there is painful constipation, a poorly defined yet clinically encountered entity. The present article reviews the current knowledge about painful constipation, trying to put together the scarce data available, and to frame it in the more general context of chronic constipation.

  17. Logical Entity Level Sentiment Analysis

    DEFF Research Database (Denmark)

    Petersen, Niklas Christoffer; Villadsen, Jørgen

    2017-01-01

    We present a formal logical approach using a combinatory categorial grammar for entity level sentiment analysis that utilizes machine learning techniques for efficient syntactical tagging and performs a deep structural analysis of the syntactical properties of texts in order to yield precise...... results. The method should be seen as an alternative to pure machine learning methods for sentiment analysis, which are argued to have high difficulties in capturing long distance dependencies, and can be dependent on significant amount of domain specific training data. The results show that the method...

  18. MERA: Musical Entities Reconciliation Algorithm

    OpenAIRE

    Fernández Álvarez, Daniel

    2015-01-01

    En este trabajo pretendemos aportar una mejora para la tarea específica del reconocimiento de entradas equivalentes en fuentes de datos relacionadas con el mundo de la música. Para ello presentamos MERA (Musical Entities Reconciliation Architecture), la arquitectura de un sistema diseñado para encontrar vínculos de equivalencia entre distintos elementos que sin embargo hacen referencia a la misma realidad. MERA está diseñado para poder adaptar el proceso de reconciliación a la naturaleza de l...

  19. Maxillary Osteomyelitis: A Rare Entity

    Directory of Open Access Journals (Sweden)

    Ayaaz Habib

    2016-01-01

    Full Text Available Osteomyelitis of the maxilla is now a rare event with the advent of antibiotics. The two predominant causes are odontogenic infections and sinusitis. Immunocompromised states such as diabetes, HIV, and malnutrition increase the risk of osteomyelitis. It is important to recognize this early as it is a difficult entity to treat with potentially serious consequences. We report an unusual case of right sided maxillary osteomyelitis in a lady with poorly controlled diabetes in rural Lincolnshire. Biopsy of the right maxillary bone showed features of acute osteomyelitis. This responded well to a prolonged course of oral antibiotics.

  20. High performance of solvothermally prepared VO2(B) as anode for aqueous rechargeable lithium batteries

    OpenAIRE

    Milošević Sanja; Stojković Ivana; Mitrić Miodrag; Cvjetićanin Nikola

    2015-01-01

    The VO2 (B) was synthesized via a simple solvothermal route at 160oC in ethanol. The initial discharge capacity of VO2 (B) anode, in saturated aqueous solution of LiNO3, was 177 mAh g-1 at a current rate of 50 mA g-1. After 50 cycles capacity fade was 4%, but from 20th-50th cycle no capacity drop was observed. The VO2 (B) has shown very good cyclability at current rate of even 1000 mA g-1 with initial discharge capacity of 92 mAh g-1. The excellent electroc...

  1. LEGAL ENTITIES IN ROMANIAN PRIVATE INTERNATIONAL LAW

    Directory of Open Access Journals (Sweden)

    Berlingher Remus Daniel

    2013-12-01

    Full Text Available Legal entities play an increasing role in international economic relations, as well as in political, cultural, social or human relations. Any legal entity is subject to the law of a certain country, as it can only exist or function on the basis of legal provisions. In this sense, the paper analyses the law applicable to the organic statute of a legal entity, the importance and criteria underlying the establishment of a legal entity’s nationality, the recognition of foreign legal entities in Romania, as well as the rights and obligations of foreign legal entities residing in our country.

  2. Collagenous Gastritis: A Rare Entity

    Directory of Open Access Journals (Sweden)

    Faten Limaiem

    2015-06-01

    Full Text Available Collagenous gastritis is a rare entity of unknown etiology characterized histologically by the presence of a thick subepithelial collagen band associated with an inflammatory infiltrate of gastric mucosa. A 40-year-old male presented with a history of chronic intermittent abdominal pain for about 6 months. Physical examination was unremarkable, and biological tests were within normal range. The patient underwent esophagogastroduodenoscopy and colonoscopy which showed a nodular mucosa of the stomach. Biopsies of the duodenum and colon were unremarkable. However, biopsies of the gastric fundus revealed a mild chronic gastritis characterized by lymphocytic and plasma cell infiltration of deep mucosa, without lymphoid follicle formation or active inflammation. No microorganisms were identified on routine hematoxylin and eosin or Giemsa-stained sections. Subepithelial collagen in the gastric biopsies was thickened and showed entrapped capillaries. Subepithelial collagen was highlighted by Masson's trichrome staining and was negative for amyloid by Congo Red. In the areas containing thickened collagen, there were no intraepithelial lymphocytes. The final pathological diagnosis was collagenous gastritis. Collagenous gastritis is an extremely rare disease, but it is important to recognize its characteristic endoscopic and pathologic findings to make a correct diagnosis. Specific therapy for this rare entity has not yet been established. [J Interdiscipl Histopathol 2015; 3(2.000: 68-70

  3. In situ formation of reduced graphene oxide structures in ceria by combined sol–gel and solvothermal processing

    Directory of Open Access Journals (Sweden)

    Jingxia Yang

    2016-11-01

    Full Text Available Raman and IR investigations indicated the presence of reduced graphene oxide (rGO-like residues on ceria nanoparticles after solvothermal treatment in ethanol. The appearance of such structures is closely related to cerium tert-butoxide as precursor and ethanol as solvothermal solvent. The rGO-like residues improve the catalytic CO oxidation activity. This was also confirmed by introduction of “external” graphene oxide during sol–gel processing, by which the rGO structures and the catalytic activity were enhanced.

  4. Some studies on ceria–zirconia reinforced solvothermally synthesized cordierite nano-composites

    Energy Technology Data Exchange (ETDEWEB)

    Srivastava, Abhinav, E-mail: srivasabhinav@gmail.com; Singh, Vinay Kumar; Kumar, Vijay; Hemanth Kumar, P.; Tripathi, Himanshu; Chaudhary, Ashish; Asiwal, Krit; Pandey, Rahul; Suman, Shyam Kumar

    2014-02-15

    Graphical abstract: -- Highlights: • Nanocordierite synthesized through solvo-thermal process. • [CeO{sub 2(0.12)}]⋅[ZrO{sub 2(0.88)}] processed by gelation and co-precipitation method. • The effect of mineralizer addition on cordierite formation was studied. • Investigation of thermo-mechanical properties of prepared nano-composites. -- Abstract: Nanostructured cordierite and 12 mol% ceria stabilized zirconia were chemically prepared separately. Pure cordierite was synthesized solvothermally, whereas [(Zr){sub 0.88}(Ce){sub 0.12}O{sub 2}] termed as CeSZ was processed with gelation and co-precipitation method. The evolution of crystalline phases and the microstructures have been studied using X-ray diffractometer, and FE-SEM with EDX. Varying contents (0–20 weight%) of CeSZ were then mixed with cordierite to form sample blocks of desired shapes. These nano-composite blocks were fired at 1100–1400 °C for a soaking time of 3 h to observe their thermo-mechanical, micro-structural and physical properties. Results indicate that ceria not only acts as a stabilizer in zirconia ceramics but it also acts as a sintering aid in cordierite formation. CeO{sub 2} also improves compressibility and structural properties of nano-composites. Sintering temperature also plays an important role in the behavior of nano-composite blocks. All properties show a major improvement than previous reported data’s.

  5. Rapid synthesis of zeolitic imidazolate framework-8 (ZIF-8) nanocrystals in an aqueous system

    KAUST Repository

    Pan, Yichang

    2011-01-01

    We report here the first example of ZIF materials synthesized in aqueous solution. The synthesis was performed at room temperature and typically took several minutes compared to hours and days in non-aqueous conditions. The obtained product were ZIF-8 nanocrystals having size of ∼85 nm and showed excellent thermal, hydrothermal and solvothermal stabilities. © 2011 The Royal Society of Chemistry.

  6. Viruses: are they living entities?

    Science.gov (United States)

    Pennazio, Sergio

    2011-01-01

    The essence (living or nonliving entities) of viruses has today become an aporia, i.e. a difficulty inherent in reasoning because they shared four fundamental characteristics with livings (multiplication, genetic information, mutation and evolution) without having the capacity to have an independent life. For much time, however, they were considered minuscule pathogenetic micro-organisms in observance of Koch and Pasteur's 'germ theory' albeit no microbiologist could show their existence except their filterability and pathogenetic action. Only some voices based on experimental results raised against this dogmatic view, in particular those of Beijerinck, Baur and Mrowka, without dipping effectively into the dominant theory. The discovery relative to their nucleoprotein nature made between 1934 and 1936 (Schlesinger as for the phage, and Bawden and co-operators as for Tobacco mosaic virus; TMV), together with the first demonstrations of their structures thanks to electron microscopy (from 1939 onwards) started on casting a new light on their true identity, which could be more clearly identified when, from 1955 onwards, phage and TMV proved to be decisive factors to understand the strategies of replication of the genetic material. Following the new knowledge, the theoretical view relative to viruses changed rather radically and the current view looks on these pathogenetic agents as nonliving aggregates of macromolecules provided with biological properties. There is, however, a current of thought, made explicitly by Lwoff that places viruses as compromise between living and non living and, perhaps, as primitive forms of life which have had great importance for the evolution of cellular life. At any rate, viruses are peculiar entities whose importance cannot be unacknowledged.

  7. Named Entity Resources - Overview and Outlook

    OpenAIRE

    Calzolari, Nicoletta; Choukri, Khalid; Declerck, Thierry; Grobelnik, Marko; Maegaard, Bente; Mariani, Joseph; Moreno, Asuncion; Odijk, Jan; Piperidis, Stelios; Ehrmann, Maud; Nouvel, Damien; Rosset, Sophie

    2016-01-01

    Recognition of real-world entities is crucial for most NLP applications. Since its introduction some twenty years ago, named entity processing has undergone a significant evolution with, among others, the definition of new tasks (e.g. entity linking) and the emergence of new types of data (e.g. speech transcriptions, micro-blogging). These pose certainly new challenges which affect not only methods and algorithms but especially linguistic resources. Where do we stand with respect to named ent...

  8. Robust Named Entity Recognition in Idiosyncratic Domains

    OpenAIRE

    Arnold, Sebastian; Gers, Felix A.; Kilias, Torsten; Löser, Alexander

    2016-01-01

    Named entity recognition often fails in idiosyncratic domains. That causes a problem for depending tasks, such as entity linking and relation extraction. We propose a generic and robust approach for high-recall named entity recognition. Our approach is easy to train and offers strong generalization over diverse domain-specific language, such as news documents (e.g. Reuters) or biomedical text (e.g. Medline). Our approach is based on deep contextual sequence learning and utilizes stacked bidir...

  9. Entity resolution in the web of data

    CERN Document Server

    Christophides, Vassilis; Stefanidis, Kostas

    2015-01-01

    In recent years, several knowledge bases have been built to enable large-scale knowledge sharing, but also an entity-centric Web search, mixing both structured data and text querying. These knowledge bases offer machine-readable descriptions of real-world entities, e.g., persons, places, published on the Web as Linked Data. However, due to the different information extraction tools and curation policies employed by knowledge bases, multiple, complementary and sometimes conflicting descriptions of the same real-world entities may be provided. Entity resolution aims to identify different descrip

  10. [The nosological entity bulimia nerviosa].

    Science.gov (United States)

    López-Ibor Aliño, J J; Cervera Enguix, S

    1991-01-01

    Anorexia nervosa and bulimia nervosa are at the present moment, two well defined clinical entities among the group of the eating disorders. The psychopathological differentiation of both syndromes has a great importance for diagnosis and therapy. The authors make a phenomenological description, based on case histories of patients with diagnostics of anorexia and bulimia nervosa, and try to establish an approach to the essential symptomatology of those disorders. The presence of affective symptomatology--depressive, but not exclusively--in the eating behaviour disorders in general and particularly in bulimia nervosa, is nowadays interpreted as an unspecific emotional lability as a response to stressing situations. That is to say, it is a secondary depressive symptomatology, more than a primary mood disorder preceding or underlying bulimia. There is strong evidence in favour of a dysregulation of serotonin metabolism in patients with bulimia nervosa, in the sense of a reduced activity, which manifest itself clinically by binges with food with a high content in carbohydrates. High levels of 5-HT seem to induce increasing feelings of safety, fullness and lead to an interruption of eating. Fluoxetine and this active metabolite are selective inhibitors of the reuptake of 5-HT and their antibulimic effect could be mediated by this mechanism.

  11. Penoscrotal porokeratosis: A distinct entity

    Directory of Open Access Journals (Sweden)

    Rajiv Joshi

    2015-01-01

    Full Text Available A 26-year-old man presented with five months history of redness associated with itching and burning over the scrotum and shaft of the penis with a persistent rash on those sites. There had been no response to topical steroid and antifungal creams. Clinical examination revealed a large well-circumscribed erythematous plaque with a thready raised border with a tiny groove at its summit that involved almost two-thirds of the ventral part of the shaft of the penis. Ill-defined erythema with a granular surface was seen over the anterior scrotal skin. A 4 mm punch biopsy of the plaque on the penile shaft revealed multiple cornoid lamellae located adjacent to one another. The patient was treated with topical emollients. Follow up after four months revealed almost complete resolution of the plaque on the penile shaft. Penoscrotal porokeratosis appears to be a distinct entity in the family of porokeratotic diseases, described only in young males in their twenties with involvement of the penile shaft and anterior scrotum with severe burning and itching and histologically associated with multiple cornoid lamellae. It may represent an unusual epidermal porokeratotic reaction pattern and may be a self-resolving condition.

  12. Indium-doped ZnO nanorods grown on Si (1 1 1) using a hybrid ALD-solvothermal method

    Science.gov (United States)

    Cervantes-López, J. L.; Rangel, R.; García-Méndez, M.; Tiznado, H.; Contreras, O.; Quintana, P.; Bartolo-Pérez, P.; Alvarado-Gil, J. J.

    2017-07-01

    Atomic layer deposition (ALD) followed by microwave hydrothermal processing was successfully employed for producing doped and vertically aligned ZnO nanorod arrays with different aspect ratio. Firstly, a textured ZnO layer with preferential orientation normal to the c-axis was formed on substrate (1 1 1) silicon single crystals by means of the ALD technique. This was achieved through the decomposition of diethylzinc at 190 °C and 3.289  ×  10-4 atm, which provided an adequate template with nucleation sites, favoring further growth of vertical nanorods. Subsequently, nanorod array growth was produced on the same surfaces through solvothermal synthesis using as promoter a solution of Zn(NO3)2. In addition, growth of indium-doped ZnoO nanorods over the substrates was produced by using In(CH3COO)3 as a doping agent. The method presented allows good quality ZnO and Zn1-x In x O thin films to be obtained. Photoluminiscence spectra show clear evidence of the inclusion of indium in the ZnO matrix. The higher intensity ratio Zn0.96In0.4O/ZnO was increased 40-fold, demonstrating such an effect.

  13. Substrate-free fabrication of self-supported V2O5 nanobelt arrays by a low-temperature solvothermal method with high electrochemical performance

    Science.gov (United States)

    Xu, Haitao; Zhang, Huijuan; Liu, Li; Fang, Ling; Wang, Yu

    2016-08-01

    In the designed synthesis, self-supported NH4V3O8 nanobelt arrays were prepared via a low-temperature solvothermal method. Then the NH4V3O8 nanobelt arrays were calcined in air atmosphere. Finally, a self-supported pattern of oriented V2O5 nanobelts was obtained for the first time. Further characterization methods certified that the growth direction of NH4V3O8 nanobelts was perpendicular to the orientation plane of self-formed NH4V3O8 sheet-like substrates. As a result, the nanobelts should stretch easily on the sheet-like substrate in an oriented manner. We prove that the solvent of ethanol plays a key role in the reaction and crystal growth process. It balances the two competing oxolation and olation reactions. Furthermore, the unique pattern served as high performance a lithium-ion battery and supercapacitor. Overall, the excellent electrochemical performances, for example, outstanding rate stability, remarkable cycling capacitance and ultrahigh capacity verify that the self-supported alignments have great potential applications in lithium-ion batteries and supercapacitors.

  14. High performance of solvothermally prepared VO2(B as anode for aqueous rechargeable lithium batteries

    Directory of Open Access Journals (Sweden)

    Milošević Sanja

    2015-01-01

    Full Text Available The VO2 (B was synthesized via a simple solvothermal route at 160oC in ethanol. The initial discharge capacity of VO2 (B anode, in saturated aqueous solution of LiNO3, was 177 mAh g-1 at a current rate of 50 mA g-1. After 50 cycles capacity fade was 4%, but from 20th-50th cycle no capacity drop was observed. The VO2 (B has shown very good cyclability at current rate of even 1000 mA g-1 with initial discharge capacity of 92 mAh g-1. The excellent electrochemical performance of VO2 (B was attributed to the stability of micro-nano structures to repeated intercalation /deintercalation process, very good electronic conductivity as well as the very low charge transfer resistance in the aqueous electrolyte. [Projekat Ministarstva nauke Republike Srbije, br. III45014

  15. Code-first development with Entity Framework

    CERN Document Server

    Barskiy, Sergey

    2015-01-01

    This book is intended for software developers with some prior experience with the Microsoft .NET framework who want to learn how to use Entity Framework. This book will get you up and running quickly, providing many examples that illustrate all the key concepts of Entity Framework.

  16. Resource description framework triples entity formations using ...

    African Journals Online (AJOL)

    A method in formatting unstructured sentences from the source corpus to a specific knowledge representation such as RDF is needed. A method for RDF entity formations from a paragraph of text using statistical language model based on N-gram is introduced. The implementation of RDF entity formation is applied on ...

  17. 46 CFR 403.110 - Accounting entities.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 8 2010-10-01 2010-10-01 false Accounting entities. 403.110 Section 403.110 Shipping COAST GUARD (GREAT LAKES PILOTAGE), DEPARTMENT OF HOMELAND SECURITY GREAT LAKES PILOTAGE UNIFORM ACCOUNTING SYSTEM General § 403.110 Accounting entities. Each Association shall be a separate accounting...

  18. Periocular xanthogranuloma: A forgotten entity?

    Directory of Open Access Journals (Sweden)

    Charalampos Papagoras

    2010-03-01

    Full Text Available Charalampos Papagoras1, George Kitsos2, Paraskevi V Voulgari1, Anastasia K Zikou3, Maria I Argyropoulou3, Aikaterini Zioga4, Alexandros A Drosos11Rheumatology Clinic, Department of Internal Medicine; 2Department of Ophthalmology; 3Department of Clinical Imaging and Radiology, 4Department of Pathology, Medical School, University of Ioannina, Ioannina, GreeceAbstract: Periocular xanthogranulomatous diseases are a rare group of disorders which are characterized by a predilection to affect the orbit and ocular adnexa and special histopathological features, in particular infiltrates comprising non-Langerhans-derived foamy histiocytes and Touton giant cells. The differential diagnosis is difficult and occasionally definite diagnosis cannot be established even after clinical and histopathological findings are taken together. We describe a case of a middle-aged man who presented with a 10-year history of voluminous eyelid swelling with concomitant late-onset atopic manifestations, namely bronchial asthma and allergic rhinitis with nasal polyps. After thorough clinical and laboratory investigation, including a biopsy of the eyelid, we classified the patient’s disease to a rare entity that has been relatively recently described: periocular xanthogranuloma associated with adult-onset asthma. In a review of the literature, no prospective trials concerning the treatment of this disease were found. The literature mainly contained case reports and case series in which corticosteroids and chemotherapy with alkylating agents have been reported to be beneficial. We treated our patient with a combination of oral corticosteroids and cyclophosphamide pulses and we observed substantial regression of the eyelid masses together with a normalization of systemic immunologic abnormalities.Keywords: periocular xanthogranuloma, adult-onset asthma, non-Langerhans histiocytoses, cyclophosphamide, methylprednisolone

  19. Named entity recognition in Slovene text

    Directory of Open Access Journals (Sweden)

    Tadej Štajner

    2013-12-01

    Full Text Available This paper presents an approach and an implementation of a named entity extractor for Slovene language, based on a machine learning approach. It is designed as a supervised algorithm based on Conditional Random Fields and is trained on the ssj500k annotated corpus of Slovene. The corpus, which is available under a Creative Commons CC-BY-NC-SA licence, is annotated with morphosyntactic tags, as well as named entities for people, locations, organisations, and miscellaneous names. The paper discusses the influence of morphosyntactic tags, lexicons and conjunctions of features of neighbouring words. An important contribution of this investigation is that morphosyntactic tags benefit named entity extraction. Using all the best-performing features the recognizer reaches a precision of 74% and a recall of 72%, having stronger performance on personal and geographical named entities, followed by organizations, but performs poorly on the miscellaneous entities, since this class is very diverse and consequently difficult to predict. A major contribution of the paper is also showing the benefits of splitting the class of miscellaneous entities into organizations and other entities, which in turn improves performance even on personal and organizational names. The software, developed in this research is freely available under the Apache 2.0 licence at http://ailab.ijs.si/~tadej/slner.zip, while development versions are available at https://github.com/tadejs/slner.

  20. AN EFFICIENT SEGMENTATION ALGORITHM FOR ENTITY INTERACTION

    Directory of Open Access Journals (Sweden)

    Eugene Ch'ng

    2009-04-01

    Full Text Available The inventorying of biological diversity and studies in biocomplexity require the management of large electronic datasets of organisms. While species inventory has adopted structured electronic databases for some time, the computer modelling of the functional interactions between biological entities at all levels of life is still in the stage of development. One of the challenges for this type of modelling is the biotic interactions that occur between large datasets of entities represented as computer algorithms. In real-time simulation that models the biotic interactions of large population datasets, the use of computational processing time could be extensive. One way of increasing the efficiency of such simulation is to partition the landscape so that entities need only traverse its local space for entities that falls within the interaction proximity. This article presents an efficient segmentation algorithm for biotic interactions for research related to the modelling and simulation of biological systems.

  1. Reduced graphene oxide-titanate hybrids: Morphologic evolution by alkali-solvothermal treatment and applications in water purification

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen-Phan, Thuy-Duong; Pham, Viet Hung; Kim, Eui Jung; Oh, Eun-Suok; Hur, Seung Hyun; Chung, Jin Suk [School of Chemical Engineering and Bioengineering, University of Ulsan, Daehakro 93, Nam-gu, Ulsan 680-749 (Korea, Republic of); Lee, Byunghwan [Department of Chemical Systems Engineering, Keimyung University, Sindang 1000, Dalseo-gu, Daegu 704-701 (Korea, Republic of); Shin, Eun Woo, E-mail: ewshin@mail.ulsan.ac.kr [School of Chemical Engineering and Bioengineering, University of Ulsan, Daehakro 93, Nam-gu, Ulsan 680-749 (Korea, Republic of)

    2012-03-01

    The reduced graphene oxide-titanate (RGO-Ti) hybrids were fabricated by incorporating spherical TiO{sub 2} nanoparticles with graphene oxide (GO) layers in aqueous NaOH solution following by the solvothermal treatment. The morphologic evolution of RGO-Ti hybrid by varying alkali-solvothermal temperatures has been first investigated. The titanate nanosheets peeled off, folded and scrolled into tubular structure; and eventually, cracked and destroyed to be ribbon-like shape. The chemical interaction and attachment of low-dimensional titanate onto RGO layers and the reverse order were elucidated by X-ray photoelectron spectra. The hybrids in sheet and tubular titanate structures possessed larger surface areas (>350 m{sup 2}/g) and higher pore volumes (>1 cm{sup 3}/g) than the other. The presence of RGO sheets as a two-dimensional (2D) platform for the deposition of titanate significantly promoted much better adsorptivity of dye contaminants compared to pure materials.

  2. Filamentous Biological Entities Obtained from the Stratosphere

    Science.gov (United States)

    Wainwright, Milton; Rose, Christopher E.; Baker, Alexander J.; Wickramasinghe, N. Chandra

    2013-03-01

    We previously reported the presence of large, non-filamentous, biological entities including a diatom fragment in the stratosphere at heights of between 22-27km. Here we report clear evidence for the presence of filamentous entities associated with a relatively large particle mass collected from the stratosphere. Although viable fungi have previously been isolated from the stratosphere, this is the first report of a filamentous microorganism being observed in situ on a stratospheric particle mass.

  3. Biomedical Named Entity Recognition: A Review

    OpenAIRE

    Basel Alshaikhdeeb; Kamsuriah Ahmad

    2016-01-01

    Biomedical Named Entity Recognition (BNER) is the task of identifying biomedical instances such as chemical compounds, genes, proteins, viruses, disorders, DNAs and RNAs. The key challenge behind BNER lies on the methods that would be used for extracting such entities. Most of the methods used for BNER were relying on Supervised Machine Learning (SML) techniques. In SML techniques, the features play an essential role in terms of improving the effectiveness of the recognition process. Features...

  4. CAp 2017 challenge: Twitter Named Entity Recognition

    OpenAIRE

    Lopez, Cédric; Partalas, Ioannis; Balikas, Georgios; Derbas, Nadia; Martin, Amélie; Reutenauer, Coralie; Segond, Frédérique; Amini, Massih-Reza

    2017-01-01

    The paper describes the CAp 2017 challenge. The challenge concerns the problem of Named Entity Recognition (NER) for tweets written in French. We first present the data preparation steps we followed for constructing the dataset released in the framework of the challenge. We begin by demonstrating why NER for tweets is a challenging problem especially when the number of entities increases. We detail the annotation process and the necessary decisions we made. We provide statistics on the inter-...

  5. Solvothermal growth of a ruthenium metal-organic framework featuring HKUST-1 structure type as thin films on oxide surfaces.

    Science.gov (United States)

    Kozachuk, Olesia; Yusenko, Kirill; Noei, Heshmat; Wang, Yuemin; Walleck, Stephan; Glaser, Thorsten; Fischer, Roland A

    2011-08-14

    Phase-pure crystalline thin films of a mixed-valence Ru(2)(II,III) metal-organic framework with 1,3,5-benzenetricarboxylate (btc) as a linker were solvothermally grown on amorphous alumina and silica surfaces. Based on the Rietveld refinement, the structure of Ru-MOF was assigned to be analogous to [Cu(3)(btc)(2)] (HKUST-1). This journal is © The Royal Society of Chemistry 2011

  6. Fabrication of Nanostructured TiO2 Using a Solvothermal Reaction for Lithium-ion Batteries

    Directory of Open Access Journals (Sweden)

    Jicai Liang

    2016-03-01

    Full Text Available Nanostructured TiO2 was successfully synthesized via a facile one-pot solvothermal reaction followed by calcina‐ tion. Hydrolysis and polycondensation of titanium butox‐ ide (Ti(OR4 were performed in the presence of sodium dodecylbenzenesulfonate (SDBS. The morphologies, crystallinity and compositions of obtained samples were identified by the methods of X-ray diffraction (XRD, Brunauer–Emmett–Teller (BET and transmission electron microscopy (TEM. It was found that the nanostructured TiO2 with an average diameter of 10±5 nm had the crystal type of anatase. A good specific surface was also obtained by the standard multipoint BET method (119.2 m2/g. As the anode materials for the lithium-ion batteries (LIBs, the anatase phase TiO2 demonstrated a relatively high gravi‐ metric specific capacity of 264.8 mAh g-1. The reversible capacity of TiO2 remained 196.4 mAh g-1 at a rate of 0.2 ̊C after 100 cycles. It indicated that this kind of TiO2 possessed a good electrochemical performance.

  7. Influence of Solvothermal Temperatures and Times on Crystallinity and Morphology of MOF-5

    Directory of Open Access Journals (Sweden)

    Tri Ana Mulyati

    2015-07-01

    Full Text Available MOF-5 (metal-organic frameworks-5 have been synthesized using solvothermal method in which reaction mixtures of zinc nitrate hexahydrate and 1,4-benzenedicarboxylic acid (BDC in dimethylformamide (DMF were heated at various heating temperatures and times in order to observe the influence of heating temperature and time on crystallinity and morphology of the obtained MOF-5. The heating temperatures used were 105, 120 and 140 °C, respectively with heating times of 12–144 h. Determination of the best reaction conditionswas based on the observation of phase purity and crystal morphology of MOF-5 using XRD and SEM. The characterization results showed that MOF-5 crystals with a higher crystallinity were obtained when the reaction mixtures were heated at 105 °C for 144 h, 120 °C for 24 h or 140 °C for 12 h. The maximum weight of MOF-5 crystal was generated from reaction mixture heated at 120 °C for 72 h.

  8. CREATIVE ACCOUNTING TECHNIQUES ON EQUITY AND LIABILITIES TO TOURISM ENTITIES

    Directory of Open Access Journals (Sweden)

    Luminita PAIUSAN

    2017-12-01

    Full Text Available Our research is topical in the context in which accounting takes an increasingly important role in the social life of each individual and implicitly of the society it belongs to and aims to present the alternative accounting concepts and practices of creative accounting on equity and liabilities to tourism entities. In determining the arguments to justify the real need for knowledge in this area we must delineate the research field Creative Accounting. In this sense, the research envisaged a systematization and reconsideration as well a synthesis and antithesis of the concepts presented on this topic in the specialized literature, in the regulations of various professional bodies and authorities. The knowledge of the patrimonial system, of its capacity to generate profits at a time is insured with both accounting and an accurate and effective control.

  9. Study of structural and optical properties of CaMoO{sub 4} nanoparticles synthesized by the microwave-assisted solvothermal method

    Energy Technology Data Exchange (ETDEWEB)

    Botelho, G., E-mail: gleice.lorena@gmail.com [INCTMN-UFSCar, Universidade Federal de São Carlos, P.O. Box 676, 13565-905, São Carlos, SP (Brazil); Nogueira, I.C. [Instituto Federal do Maranhão, PPG em Engenharia de Materiais, 65030-005, São Luís, MA (Brazil); Moraes, E. [INCTMN-UFSCar, Universidade Federal de São Carlos, P.O. Box 676, 13565-905, São Carlos, SP (Brazil); Longo, E. [INCTMN-UNESP, Universidade Estadual Paulista, P.O. Box 355, CEP, 14801-907, Araraquara, SP (Brazil)

    2016-11-01

    Calcium molybdate (CaMoO{sub 4}) nanoparticles were synthesized by using a rapid assisted-microwave solvothermal method. X-ray diffraction measurements, Fourier transform Raman and Fourier transform infrared spectroscopies, revealed that the samples all have a scheelite-type tetragonal structure. In addition, the data obtained from the Rietveld refinements revealed distortions of the [Ca−O] and [Mo−O] bonds that led, in turn, to distortions of the [CaO{sub 8}] and [MoO{sub 4}] clusters. The presence of irregular spherical-like CaMoO{sub 4} nanoparticles and the corresponding crystallographic arrangement were confirmed and determined via transmission electron microscopy and high resolution transmission electron microscopy, respectively. First-principles quantum mechanical calculations based on the density functional theory at the B3LYP level were employed in order to understand the band structure and density of states of CaMoO{sub 4} in the excited singlet and triplet states. Furthermore, the optical properties were investigated by performing ultraviolet–visible spectroscopy and photoluminescence (PL) measurements. Maximum PL emission of CaMoO{sub 4} powders was detected in the green-region wavelength of the electromagnetic spectrum; this emission was attributed to the distorted [MoO{sub 4}] clusters. - Highlights: • Effect of propane-1,3-diol in the synthesis of nanoparticles by a rapid method. • Utilization of first-principles quantum mechanical calculations. • Investigation of photoluminescent properties of CaMoO{sub 4} nanoparticles.

  10. Ranking Entities in Networks via Lefschetz Duality

    DEFF Research Database (Denmark)

    Aabrandt, Andreas; Hansen, Vagn Lundsgaard; Poulsen, Bjarne

    2014-01-01

    In the theory of communication it is essential that agents are able to exchange information. This fact is closely related to the study of connected spaces in topology. A communication network may be modelled as a topological space such that agents can communicate if and only if they belong...... then be ranked according to how essential their positions are in the network by considering the effect of their respective absences. Defining a ranking of a network which takes the individual position of each entity into account has the purpose of assigning different roles to the entities, e.g. agents...

  11. Xanthogranulomatous Prostatitis, a Rare Prostatic Entity

    Directory of Open Access Journals (Sweden)

    Alejandro Noyola

    2017-01-01

    Full Text Available There are several benign prostatic pathologies that can clinically mimic a prostate adenocarcinoma. Xanthogranulomatous prostatitis is a benign inflammatory condition of the prostate and a rare entity. A 47-year old male, with 3 years of lower urinary tract symptoms, with a palpable hypogastric tumor, digital rectal examination: solid prostate, of approximately 60 g. Initial PSA was 0.90 ng/mL. He underwent surgical excision of the lower abdominal nodule and prostatectomy. Histopathology showed xanthogranulomatous prostatitis, without malignancy. Xanthogranulomatous prostatitis is an extremely rare entity that can simulate prostate adenocarcinoma, therefore having a correct histopathological diagnosis is essential.

  12. Cross domains Arabic named entity recognition system

    Science.gov (United States)

    Al-Ahmari, S. Saad; Abdullatif Al-Johar, B.

    2016-07-01

    Named Entity Recognition (NER) plays an important role in many Natural Language Processing (NLP) applications such as; Information Extraction (IE), Question Answering (QA), Text Clustering, Text Summarization and Word Sense Disambiguation. This paper presents the development and implementation of domain independent system to recognize three types of Arabic named entities. The system works based on a set of domain independent grammar-rules along with Arabic part of speech tagger in addition to gazetteers and lists of trigger words. The experimental results shown, that the system performed as good as other systems with better results in some cases of cross-domains corpora.

  13. A generative language modeling approach for ranking entities

    NARCIS (Netherlands)

    Weerkamp, W.; Balog, K.; Meij, E.

    2009-01-01

    We describe our participation in the INEX 2008 Entity Ranking track. We develop a generative language modeling approach for the entity ranking and list completion tasks. Our framework comprises the following components: (i) entity and (ii) query language models, (iii) entity prior, (iv) the

  14. Awareness of Entities, Activities and Contexts in Ambient Systems

    DEFF Research Database (Denmark)

    Kristensen, Bent Bruun

    2013-01-01

    Ambient systems are modeled by entities, activities and contexts, where entities exist in contexts and engage in activities. A context supports a dynamic collection of entities by services and offers awareness information about the entities. Activities also exist in contexts and model ongoing...

  15. Novel Nano Boehmite prepared by Solvothermal reaction of aluminum hydroxide gel in Monoethanolamine

    Science.gov (United States)

    Ohta, Yasuhiro; Hayakawa, Tomokatsu; Inomata, Tomohiko; Ozawa, Tomohiro; Masuda, Hideki

    2017-07-01

    Solvothermal reaction of aluminum hydroxide gel (AHG) in monoethanolamine (MEA) was studied at several temperatures (100, 120, 150, and 200 °C) in several reaction times (2, 3, 4, 5, 6, and 13 h). The reaction product prepared at a low temperature of 120 °C in the reaction time more than 6 h gave a blue photoluminescence nanoboehmite intercalated with monoethanolamine derivatives (BM-MEA) in the colloidal solution, which showed a photoluminescence emission centered at 420 nm with an excitation of 360 nm. The powdery samples recovered from the reaction products were characterized by using elemental analysis, XRD analysis, IR spectroscopy, thermogravimetric (TG)-DTA, 13C and 27Al CP/MAS NMR spectroscopies, N2 gas adsorption/desorption isotherm, SEM and TEM images, and photoluminescence spectroscopy. The X-ray diffraction revealed that the basal space in BM-MEA was expanded from 0.61 to 1.2 nm by intercalation of MEA derivatives to boehmite, and the IR and 13C CP/MAS NMR spectra determined that the intercalated MEA derivatives are protonated- and carbamate-substituted MEAs, which are formed in the layers through a covalent bond with Al-OH groups on boehmite surface. The empirical formula of BM-MEA was estimated to be AlO(OH)0.82(OCH2CH2NH3 +)0.05(OCH2CH2NHCOO-)0.13 on the basis of the elemental TG-DTA and IR spectral analyses. We discuss the reaction mechanism of a unique blue photoluminescence BM-MEA formed by proceeding in CO2-H2O-alkanolamine system.

  16. Efficient solvothermal wet in situ transesterification of Nannochloropsis gaditana for biodiesel production.

    Science.gov (United States)

    Kim, Bora; Chang, Yong Keun; Lee, Jae W

    2017-05-01

    In situ transesterification of wet microalgae is a promising, simplified alternative biodiesel production process that replaces multiple operations of cell drying, extraction, and transesterification reaction. This study addresses enhanced biodiesel production from Nannochloropsis gaditana at elevated temperatures. Compared with the previously reported in situ transesterification process of conducting the reaction at a temperature ranging from 95 to 125 °C, the present work employs higher temperatures of at least 150 °C. This relatively harsh condition allows much less acid catalyst with or without co-solvent to be used during this single extraction-conversion process. Without any co-solvent, 0.58% (v/v) of H 2 SO 4 in the reaction medium can achieve 90 wt% of the total lipid conversion to biodiesel at 170 °C when the moisture content of wet algal paste is 80 wt%. Here, the effects of temperature, acid catalyst, and co-solvent on the FAEE yield and specification were scrutinized, and the reaction kinetic was investigated to understand the solvothermal in situ transesterification reaction at the high temperature. Having a biphasic system (water/chloroform) during the reaction also helped to meet biodiesel quality standard EN 14214, as Na + , K + , Ca 2+ , Mg 2+ cations and phosphorus were detected only below 5 ppm. With highlights on the economic feasibility, wet in situ transesterification at the high temperature can contribute to sustainable production of biodiesel from microalgae by reducing the chemical input and relieve the burden of extensive post purification process, therefore a step towards green process.

  17. Novel multiform morphologies of hydroxyapatite: Synthesis and growth mechanism

    Energy Technology Data Exchange (ETDEWEB)

    Mary, I. Reeta [Department of Nanoscience and Technology, Bharathiar University, Coimbatore 641046 (India); Department of Physics, Government Arts College, Coimbatore 641018 (India); Sonia, S.; Viji, S.; Mangalaraj, D.; Viswanathan, C. [Department of Nanoscience and Technology, Bharathiar University, Coimbatore 641046 (India); Ponpandian, N., E-mail: ponpandian@buc.edu.in [Department of Nanoscience and Technology, Bharathiar University, Coimbatore 641046 (India)

    2016-01-15

    Graphical abstract: - Highlights: • Novel multiform morphologies of hydroxyapatite from nanoscale building blocks. • Facile hydro/solvothermal method under mild reaction conditions without the necessity of post-annealing treatment. • Growth mechanism by Ostwald ripening and self-assembly processes. - Abstract: Morphological evolution of materials becomes a prodigious challenge due to their key role in defining their functional properties and desired applications. Herein, we report the synthesis of hydroxyapatite (HAp) microstructures with multiform morphologies, such as spheres, cubes, hexagonal rods and nested bundles constructed from their respective nanoscale building blocks via a simple cost effective hydro/solvothermal method. A possible formation mechanism of diverse morphologies of HAp has been presented. Structural analysis based on X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy confirms the purity of the HAp microstructures. The multiform morphologies of HAp were corroborated by using Field emission scanning electron microscope (FESEM).

  18. 78 FR 31822 - Unincorporated Business Entities

    Science.gov (United States)

    2013-05-28

    ... (System) institutions' use of unincorporated business entities (UBEs) organized under State law for certain business activities. A UBE includes limited partnerships (LPs), limited liability partnerships... 12 CFR Parts 604, 611, 612, 619, 620, 621, 622, 623, and 630 RIN 3052-AC65 Unincorporated Business...

  19. A Rare Entity: A Case Report

    African Journals Online (AJOL)

    abp

    2014-07-26

    Jul 26, 2014 ... 1. Melorheostosis: a rare entity: a case report. Abdelhakim Kherfani1, Hachem Mahjoub1,&. 1A Orthopedics adults surgery department, MT Kassab Institute, La Manouba, Tunisia. &Corresponding author: Hachem Mahjoub, Orthopedics adults surgery department, MT Kassab Institute, La Manouba, Tunisia.

  20. Using Wikipedia's category structure for entity search

    NARCIS (Netherlands)

    Kaptein, R.; Kamps, J.

    2013-01-01

    In this paper we investigate how the category structure of Wikipedia can be exploited for Entity Ranking. In the last decade, theWeb has not only grown in size, but also changed its character, due to collaborative content creation and an increasing amount of structure. Current Search Engines find

  1. Xanthogranulomatous Endometritis: An Unusual Pathological Entity ...

    African Journals Online (AJOL)

    Xanthogranulomatous inflammation is a well‑established histological entity characterized by xanthogranuloma which is composed of foamy histiocytes, lymphocytes, plasma cells, and variable number of foreign body giant cells. It is known to affect several organs, especially kidney, gall bladder, salivary glands, and bones.

  2. 13 CFR 130.200 - Eligible entities.

    Science.gov (United States)

    2010-01-01

    ... or university; (3) A college or school of business, engineering, commerce or agriculture; (4) A... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Eligible entities. 130.200 Section 130.200 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION SMALL BUSINESS DEVELOPMENT...

  3. 31 CFR 800.212 - Foreign entity.

    Science.gov (United States)

    2010-07-01

    ... 31 Money and Finance: Treasury 3 2010-07-01 2010-07-01 false Foreign entity. 800.212 Section 800.212 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) OFFICE OF INVESTMENT SECURITY, DEPARTMENT OF THE TREASURY REGULATIONS PERTAINING TO MERGERS, ACQUISITIONS, AND...

  4. Leiomyosarcoma of the Penis, an Exceptional Entity

    Directory of Open Access Journals (Sweden)

    Edwin Javier Romero Gonzalez

    2015-05-01

    Full Text Available In tumors of the penis, mesenchymal tumors are extremely rare and within them, sarcomas are exceptional. We report a patient with a sarcomatous lesion treated with conservative surgery with good surgical outcome and the review of the literature, to present the latest advances in the treatment of this unusual entity.

  5. Xanthogranulomatous endometritis: an unusual pathological entity ...

    African Journals Online (AJOL)

    Xanthogranulomatous endometritis is an unusual pathological entity mimicking endometrial carcinoma. This shows sheets of foamy histiocytes alongwith other inflammatory cells. We, hereby, report a case of 45 year multigravida female with irregular menstrual history, clinically diagnosed as carcinoma and ...

  6. Xanthogranulomatous Endometritis: An Unusual Pathological Entity ...

    African Journals Online (AJOL)

    Department of Pathology, Adesh. Institute of Medical Sciences and. Research, Bathinda, India. E‑mail: drmanishamakkar@yahoo.co.in. Introduction. Xanthogranulomatous inflammation is a well‑established histological entity characterized by xanthogranuloma which is composed of foamy histiocytes, lymphocytes, plasma ...

  7. Graph Convolutional Networks for Named Entity Recognition

    OpenAIRE

    Cetoli, A.; Bragaglia, S.; O'Harney, A. D.; Sloan, M.

    2017-01-01

    In this paper we investigate the role of the dependency tree in a named entity recognizer upon using a set of GCN. We perform a comparison among different NER architectures and show that the grammar of a sentence positively influences the results. Experiments on the ontonotes dataset demonstrate consistent performance improvements, without requiring heavy feature engineering nor additional language-specific knowledge.

  8. 31 CFR 800.211 - Entity.

    Science.gov (United States)

    2010-07-01

    ... 31 Money and Finance: Treasury 3 2010-07-01 2010-07-01 false Entity. 800.211 Section 800.211 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) OFFICE OF INVESTMENT SECURITY, DEPARTMENT OF THE TREASURY REGULATIONS PERTAINING TO MERGERS, ACQUISITIONS, AND TAKEOVERS BY...

  9. Hierarchically solvothermal synthesis of WO3-based nanocomposite: Nature-inspired structure and enhanced gas-sensing property

    Science.gov (United States)

    Long, Huiwu; Zeng, Wen; Li, Tianming

    2017-04-01

    Composed of the heart, cardiac valves and blood vessels, the blood circulation system can manage the aggregation and the movement of the blood regularly and efficiently. Due to the analogical fluidity of the charge carrier and the blood, such system may act as the inspiration to design the advanced gas-sensing material. As a proof-of-concept, firstly, the porous WO3 monomer was synthesized and recombined with the one-dimensional NiO monomer through the P-N junction to construct a similar structure. Subsequently, a series of gas-sensing tests towards the ethanol were measured. The obtained result indicates this nature-inspired nanocomposite indeed shows an enhanced gas-sensing property towards the ethanol, testifying the rationality of our design.

  10. Simple synthesis of porous melamine-formaldehyde resins by low temperature solvothermal method and its CO2 adsorption properties

    Directory of Open Access Journals (Sweden)

    F. Yin

    2017-11-01

    Full Text Available A simple and environmentally-friendly approach for the preparation of porous melamine-formaldehyde resins (PMFRs was developed by using low-boiling-point solvents, such as water, as pore-forming agent. With using dimethyl sulfoxide (DMSO and low-boiling solvents cosolvent method, PMFRs with a high specific surface area and well-defined pore structure can be synthesized at a low reaction temperature of 140 °C for a short reaction duration in 20 hours, which can replace the conventional methods that use dimethyl sulfoxide (DMSO as reaction medium and require 3 days at 170 °C to achieve similar surface area. When loaded with polyethylenimine (PEI, the PMFR-PEI-30% showed good CO2 adsorption performance with a capacity of up to 2.89 mmol/g at 30 °C. These results bring new perspectives for the development of lowcost and environmentally-friendly synthetic methods for porous materials, which can boost their widespread applications.

  11. Enhanced microbial electrosynthesis with three-dimensional graphene functionalized cathodes fabricated via solvothermal synthesis

    DEFF Research Database (Denmark)

    Aryal, Nabin; Halder, Arnab; Tremblay, Pier-Luc

    2016-01-01

    The biological reduction of CO2 into multicarbon chemicals can be driven by electrons derived from the cathode of a bioelectrochemical reactor via microbial electrosynthesis (MES). To increase MES productivity, conditions for optimal electron transfer between the cathode and the microbial catalys...

  12. Continuous Solvothermal Synthesis and Surface Treatment for Improved and Scalable Processing of Ultra High Temperature Ceramic (UHTC) Nanopowders

    Science.gov (United States)

    2017-06-13

    b) coated with PEDAB; (c) coated with PBAB .............. 63 TABLES Table 1: Solvent ranking for suspending ZrB2 nanoparticles ...with homogeneous nonagglomerated nanoparticles ,20 smudge- and stain-resistant coatings , antibody bonding to phosphor particles, and more. A series...composite materials or protective coating via a simple processing technique. This idea was outside the original scope of synthesizing nanoparticles

  13. Dialkylamide as Both Capping Agent and Surfactant in a Direct Solvothermal Synthesis of Magnetite and Titania Nanoparticles

    Czech Academy of Sciences Publication Activity Database

    Cara, C.; Musinu, A.; Mameli, V.; Ardu, A.; Nižňanský, D.; Buršík, Josef; Scorciapino, M. A.; Manzo, G.; Cannas, C.

    2015-01-01

    Roč. 15, č. 5 (2015), s. 2364-2372 ISSN 1528-7483 R&D Projects: GA ČR(CZ) GA14-18392S Institutional support: RVO:61388980 Keywords : Nanomagnetics * Nanoparticles * Nuclear magnetic resonance * Fourier transform infrared spectroscopy Subject RIV: CA - Inorganic Chemistry Impact factor: 4.425, year: 2015

  14. Microstrucural and optical properties of SnO{sub 2} nanoparticles formed by using a solvothermal synthesis method

    Energy Technology Data Exchange (ETDEWEB)

    Kwak, Jin Ku; Park, Kyung Hoon; Yun, Dong Yeol; Lee, Dea Uk; Kim, Tae Whan; Son, Dong Ick [Hanyang University, Seoul (Korea, Republic of); Han, Jun Hee; Lee, Jeong Young [Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of)

    2010-12-15

    Self-assembled SnO{sub 2} nanoparticles embedded in a poly(4-vinylphenol) (PVP) polymer layer were formed by using spin coating. X-ray photoelectron spectroscopy spectra showed that Sn 3d and O 1s peaks corresponding to the SnO{sub 2} nanoparticles appeared, indicative of the formation of SnO{sub 2} nanoparticles. Bright-field transmission electron microscopy image and selected area electron diffraction patterns showed that the SnO{sub 2} nanoparticles were randomly distributed in the PVP layer. Photoluminescence spectra for the synthesized SnO{sub 2} nanoparticles in a dibutyl ether solution showed that the dominant exciton peak corresponded to the band-edge emission was observed.

  15. Magnetic field-induced solvothermal synthesis of one-dimensional assemblies of Ni-Co alloy microstructures

    National Research Council Canada - National Science Library

    Hu, Ming Jun; Lin, Bin; Yu, Shu Hong

    2008-01-01

    One-dimensional magnetic Ni-Co alloy microwires with different microstructures and differently shaped building blocks including spherical particles, multilayer stacked alloy plates, and alloy flowers...

  16. Cross domains Arabic named entity recognition system

    KAUST Repository

    Al-Ahmari, S. Saad

    2016-07-11

    Named Entity Recognition (NER) plays an important role in many Natural Language Processing (NLP) applications such as; Information Extraction (IE), Question Answering (QA), Text Clustering, Text Summarization and Word Sense Disambiguation. This paper presents the development and implementation of domain independent system to recognize three types of Arabic named entities. The system works based on a set of domain independent grammar-rules along with Arabic part of speech tagger in addition to gazetteers and lists of trigger words. The experimental results shown, that the system performed as good as other systems with better results in some cases of cross-domains corpora. © (2016) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.

  17. Regulations in establishing and developing urban entities

    Directory of Open Access Journals (Sweden)

    Ljubić Slavoljub C.

    2009-01-01

    Full Text Available The main topic of this work is to represent relatively new method of analyzing, planning and developing various projects in different architectural fields. The concept 'pattern' symbolizes a new view on objects and items that are already exist around us or those that will be created in the future. By explaining this concept, this work focus on describing 'pattern' as a new system or 'pattern language' that identifies foundation and development of unplanned cities. Every town or urban entity symbolizes 'pattern', but it is made from various 'patterns' as well. There are certain rules i.e. patterns that particular urban entities follow in order to establish themselves and 'pattern language' has been developed on that basis. The main purpose of this work is to emphasize this phenomenon and reveal the significance that 'patterns' have in urbanism development. Their understanding is of great importance so they can be implemented not only in theoretical but also in practical examination and analysis.

  18. Generic Entity Resolution in Relational Databases

    Science.gov (United States)

    Sidló, Csaba István

    Entity Resolution (ER) covers the problem of identifying distinct representations of real-world entities in heterogeneous databases. We consider the generic formulation of ER problems (GER) with exact outcome. In practice, input data usually resides in relational databases and can grow to huge volumes. Yet, typical solutions described in the literature employ standalone memory resident algorithms. In this paper we utilize facilities of standard, unmodified relational database management systems (RDBMS) to enhance the efficiency of GER algorithms. We study and revise the problem formulation, and propose practical and efficient algorithms optimized for RDBMS external memory processing. We outline a real-world scenario and demonstrate the advantage of algorithms by performing experiments on insurance customer data.

  19. Deep Active Learning for Named Entity Recognition

    OpenAIRE

    Shen, Yanyao; Yun, Hyokun; Lipton, Zachary C.; Kronrod, Yakov; Anandkumar, Animashree

    2017-01-01

    Deep learning has yielded state-of-the-art performance on many natural language processing tasks including named entity recognition (NER). However, this typically requires large amounts of labeled data. In this work, we demonstrate that the amount of labeled training data can be drastically reduced when deep learning is combined with active learning. While active learning is sample-efficient, it can be computationally expensive since it requires iterative retraining. To speed this up, we intr...

  20. Preparation of flower-like CuS by solvothermal method and its photodegradation and UV protection

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Xiao-Sai; Shen, Yong, E-mail: shenyong@sues.edu.cn; Xu, Li-Hui; Wang, Li-Ming; Xing, Ya-Jun

    2016-07-25

    The flower-like CuS with hierarchical structures were synthesized by a solvothermal method. X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, UV–vis optical absorption spectroscopy and thermogravimetric analysis (TGA) and ultraviolet transmittance analyzer labsphere were used to characterize the as-prepared products. The results of photocatalytic degradation of Methylene blue (MB) demonstrated that the as-prepared flower-like CuS possessed high photocatalytic performance in UV and visible range and its band gap was 1.45 eV. The degradation rate of MB by CuS with the absence of H{sub 2}O{sub 2} was 98.23% and 100% under xenon lamp and Mercury tungsten blended lamp for 30 min, respectively. And a new approach for ultraviolet (UV) protection of cotton fabrics treated by flower-like CuS microspheres was innovatively investigated and the results showed that flower-like CuS was a good UV resistant material. - Highlights: • The flower-like CuS was prepared via solvothermal method. • The as-prepared CuS showed better photodegradation of MB solution under visible region. • The cotton fabric treated by the obtained flower-like CuS was proved to have a potential application in anti-UV field.

  1. Key insights on the structural characterization of textured Er{sub 2}O{sub 3}-ZrO{sub 2} nano-oxides prepared by a surfactant-free solvothermal route

    Energy Technology Data Exchange (ETDEWEB)

    Julian-Lopez, Beatriz, E-mail: julian@qio.uji.es [Departamento de Quimica Inorganica y Organica, Universitat Jaume I, Avda. Vicente Sos Baynat s/n, 12071 Castellon (Spain); Luz, Veronica de la; Gonell, Francisco; Cordoncillo, Eloisa [Departamento de Quimica Inorganica y Organica, Universitat Jaume I, Avda. Vicente Sos Baynat s/n, 12071 Castellon (Spain); Lopez-Haro, Miguel; Calvino, Jose J. [Departamento de Ciencia de los Materiales e Ingenieria Metalurgica y Quimica Inorganica, Facultad de Ciencias, Universidad de Cadiz, Campus Rio San Pedro, Puerto Real, 11510 Cadiz (Spain); Escribano, Purificacion [Departamento de Quimica Inorganica y Organica, Universitat Jaume I, Avda. Vicente Sos Baynat s/n, 12071 Castellon (Spain)

    2012-04-05

    Highlights: Black-Right-Pointing-Pointer Structural resolution of fluorite vs. pyrochlore in small nanocrystals. Black-Right-Pointing-Pointer Simple template-free solvothermal synthesis of Er{sub 2}O{sub 3}-ZrO{sub 2} nanooxides. Black-Right-Pointing-Pointer Good control over size, morphology and surface properties (280 m{sup 2} g{sup -1}). - Abstract: Zirconia-mixed oxides can exhibit cubic fluorite and pyrochlore structure. Their discrimination is not easy in nanooxides with a crystal size close to that of a few unit cells. In this work, high resolution transmission electron microscopy (HRTEM) has been employed to provide key insights on the structural characterization of a nanometric and porous mixed Er{sub 2}O{sub 3}-ZrO{sub 2} oxide. The material was prepared by a simple template-free solvothermal route that provided nanocrystalline powders at low temperature (170 Degree-Sign C) with spherical morphology, and high surface area ({approx}280 m{sup 2} g{sup -1}). The porosity was mainly originated from the assembling of organic complexing agents used in the synthesis to limit the crystal growth and to control hydrolysis and condensation reaction rates. The samples were characterized by thermal analysis, X-ray diffraction, scanning electron microscopy and N{sub 2} adsorption measurements. A detailed study by HRTEM was conducted on microtomed samples. It was observed that the material was made of nanocrystals packed into spherical agglomerates. HRTEM simulations indicated that it is not possible to identify the pyrochlore phase in nanoparticles with diameter below 2 nm. In our samples, the analysis of the HRTEM lattice images by means of fast Fourier transform (FFT) techniques revealed well defined spots that can be assigned to different planes of a cubic fluorite-type phase, even in the raw material. Raman spectroscopy was also a powerful technique to elucidate the crystalline phase of the materials with the smallest nanoparticles. HREM and Raman results evidenced

  2. Improving Named Entity Disambiguation by Iteratively Enhancing Certainty of Extraction

    NARCIS (Netherlands)

    Habib, M. B.; Keulen, M. van

    2011-01-01

    Named entity extraction and disambiguation have received much attention in recent years. Typical fields addressing these topics are information retrieval, natural language processing, and semantic web. This paper addresses two problems with named entity extraction and disambiguation. First, almost

  3. Named Entity Extraction and Disambiguation from an Uncertainty Perspective

    NARCIS (Netherlands)

    Habib, M. B.; Keulen, M. van

    2011-01-01

    Named entity extraction and disambiguation have received much attention in recent years. Typical fields addressing these topics are information retrieval, natural language processing, and semantic web. This work addresses two problems with named entity extraction and disambiguation. First, almost no

  4. Category-based query modeling for entity search

    NARCIS (Netherlands)

    Balog, K.; Bron, M.; de Rijke, M.

    2010-01-01

    Users often search for entities instead of documents and in this setting are willing to provide extra input, in addition to a query, such as category information and example entities. We propose a general probabilistic framework for entity search to evaluate and provide insight in the many ways of

  5. 76 FR 71867 - Addition of Certain Persons to the Entity List; and Implementation of Entity List Annual Review...

    Science.gov (United States)

    2011-11-21

    ... eleven Afghan entities; 0 (b) By revising under Canada, in alphabetical order, two Canadian entities; 0..., 2011. Kevin J. Wolf, Assistant Secretary for Export Administration. BILLING CODE 3510-33-P ...

  6. Pattern Mining for Named Entity Recognition

    OpenAIRE

    Nouvel, Damien; Antoine, Jean-Yves; Friburger, Nathalie

    2014-01-01

    International audience; Many evaluation campaigns have shown that knowledge-based and data-driven approaches remain equally competitive for Named Entity Recognition. Our re-search team has developed CasEN, a symbolic system based on finite state tran-ducers, which achieved promising results during the Ester2 French-speaking eval-uation campaign. Despite these encouraging results, manually extending the cov-erage of such a hand-crafted system is a difficult task. In this paper, we present a no...

  7. Neural Architectures for Named Entity Recognition

    OpenAIRE

    Lample, Guillaume; Ballesteros, Miguel; Subramanian, Sandeep; Kawakami, Kazuya; Dyer, Chris

    2016-01-01

    State-of-the-art named entity recognition systems/nrely heavily on hand-crafted features and/ndomain-specific knowledge in order to learn/neffectively from the small, supervised training/ncorpora that are available. In this paper, we/nintroduce two new neural architectures—one/nbased on bidirectional LSTMs and conditional/nrandom fields, and the other that constructs/nand labels segments using a transition-based/napproach inspired by shift-reduce parsers./nOur models rely on two sources of in...

  8. Comparison of Two Novel Solution-Based Routes for the Synthesis of Equiaxed ZnO Nanoparticles

    Directory of Open Access Journals (Sweden)

    K. Elen

    2011-01-01

    Full Text Available Due to a dominant one-dimensional growth rate, nanoparticles of zinc oxide often show a rodlike morphology. As a result, the synthesis of small spherical nanoparticles of undoped ZnO remains challenging. This paper presents two procedures that successfully produce a powder consisting of equiaxed zinc oxide nanoparticles: one using a polyethylene glycol- (PEG- assisted solvothermal method and the other by calcination of zinc oxalate obtained from a microemulsion-mediated method. In the latter, zinc-substituted aerosol OT (AOT is used as a surfactant. The samples are characterized by inductively coupled plasma-atomic emission spectroscopy (ICP-AES, thermogravimetric analysis (TGA, X-ray diffraction (XRD, Fourier transform infrared spectroscopy (FTIR, transmission electron microscopy (TEM, photon correlation spectroscopy (PCS, and photoluminescence (PL spectroscopy. Both synthesis techniques produce nanoparticles with similar sizes in the range of 10 to 20 nm. Dense aggregates observed in the calcined powder are infrequent in the case of the solvothermal method.

  9. Automatic term list generation for entity tagging.

    Science.gov (United States)

    Sandler, Ted; Schein, Andrew I; Ungar, Lyle H

    2006-03-15

    Many entity taggers and information extraction systems make use of lists of terms of entities such as people, places, genes or chemicals. These lists have traditionally been constructed manually. We show that distributional clustering methods which group words based on the contexts that they appear in, including neighboring words and syntactic relations extracted using a shallow parser, can be used to aid in the construction of term lists. Experiments on learning lists of terms and using them as part of a gene tagger on a corpus of abstracts from the scientific literature show that our automatically generated term lists significantly boost the precision of a state-of-the-art CRF-based gene tagger to a degree that is competitive with using hand curated lists and boosts recall to a degree that surpasses that of the hand-curated lists. Our results also show that these distributional clustering methods do not generate lists as helpful as those generated by supervised techniques, but that they can be used to complement supervised techniques so as to obtain better performance. The code used in this paper is available from http://www.cis.upenn.edu/datamining/software_dist/autoterm/

  10. CNN-based ranking for biomedical entity normalization.

    Science.gov (United States)

    Li, Haodi; Chen, Qingcai; Tang, Buzhou; Wang, Xiaolong; Xu, Hua; Wang, Baohua; Huang, Dong

    2017-10-03

    Most state-of-the-art biomedical entity normalization systems, such as rule-based systems, merely rely on morphological information of entity mentions, but rarely consider their semantic information. In this paper, we introduce a novel convolutional neural network (CNN) architecture that regards biomedical entity normalization as a ranking problem and benefits from semantic information of biomedical entities. The CNN-based ranking method first generates candidates using handcrafted rules, and then ranks the candidates according to their semantic information modeled by CNN as well as their morphological information. Experiments on two benchmark datasets for biomedical entity normalization show that our proposed CNN-based ranking method outperforms traditional rule-based method with state-of-the-art performance. We propose a CNN architecture that regards biomedical entity normalization as a ranking problem. Comparison results show that semantic information is beneficial to biomedical entity normalization and can be well combined with morphological information in our CNN architecture for further improvement.

  11. Solvothermal preparation of ZnO nanorods as anode material for improved cycle life Zn/AgO batteries.

    Directory of Open Access Journals (Sweden)

    Shafiq Ullah

    Full Text Available Nano materials with high surface area increase the kinetics and extent of the redox reactions, thus resulting in high power and energy densities. In this study high surface area zinc oxide nanorods have been synthesized by surfactant free ethylene glycol assisted solvothermal method. The nanorods thus prepared have diameters in the submicron range (300 ~ 500 nm with high aspect ratio. They have uniform geometry and well aligned direction. These nanorods are characterized by XRD, SEM, Specific Surface Area Analysis, solubility in alkaline medium, EDX analysis and galvanostatic charge/discharge studies in Zn/AgO batteries. The prepared zinc oxide nanorods have low solubility in alkaline medium with higher structural stability, which imparts the improved cycle life stability to Zn/AgO cells.

  12. One-pot solvothermal route to self-assembly of cauliflower-shaped CdS microspheres

    Science.gov (United States)

    Ge, Ming; Cui, Yao; Liu, Lu; Zhou, Zhen

    2011-05-01

    Nearly monodispersed cauliflower-shaped CdS microspheres were prepared through a simple one-step solvothermal route on a large scale by employing sodium dodecyl sulfate (SDS) as the surfactant. Images by field emission scanning electron microscope (FESEM) and transmission electron microscope (TEM) indicate that cauliflower-shaped CdS microspheres with diameters in the range from 1.3 to 4.5 μm are assembled by nanoparticles with an average diameter of approximately 30 nm. The possible formation mechanism of the cauliflower-shaped CdS microspheres was also proposed. The photovoltaic activity of cauliflower-shaped CdS architectures has been investigated, indicating that the as-obtained CdS microspheres exhibited higher photovoltaic performance in comparison with CdS nanoparticles.

  13. Preparation of flower-like CuS by solvothermal method for photocatalytic, UV protection and EMI shielding applications

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Xiao-Sai; Shen, Yong, E-mail: shenyong@sues.edu.cn; Xu, Li-Hui; Wang, Li-Ming; Lu, Li-sha; Zhang, Ya-ting

    2016-11-01

    Highlights: • The flower-like CuS was synthesized by a facil solvothermal method. • The as-prepared flower-like CuS showed better solar light-driven photocatalytic activity. • The as-prepared CuS could act as a novel UV blocker. • The flower-like CuS potentially hold promise as electromagnetic shielding material. - Abstract: The flower-like CuS hierarchical structures were synthesized by solvothermal method. The as-prepared products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared(FTIR) spectroscopy, UV–vis optical absorption spectroscopy and thermogravimetric analysis (TGA). The results demonstrated that the as-prepared flower-like CuS with the diameter of 1–5 um was pure hexagonal phase CuS and had well-defined flower-like structures. (1) The as-prepared CuS was proved to possess high photocatalytic performance with band gap of 1.45 eV. The degradation rate of Methylene blue (MB) was up to, 98.26%, 100% after 30 min under UV and visible irradiation. (2)The UPF of cotton fabric treated with CuS reached up to 174 compared with the original untreated fabric with the UPF 20.62. (3) The electromagnetic interference shielding effectiveness (EMI SE) of CuS coating was up to 27–31 dB when the content of CuS increased to 28.6%wt in the frequency of 300 KHz–3 GHz. Furthermore, the influence of reaction conditions on the morphology of the as-prepared CuS was investigated systematically and the possible formation mechanism of the CuS hierarchical structure was also proposed.

  14. Highly effective synthesis of a cobalt(ii) metal-organic coordination polymer by using continuous flow chemistry.

    Science.gov (United States)

    Gong, Chunhua; Zhang, Junyong; Zeng, Xianghua; Xie, Jingli

    2016-12-20

    The coordination polymer [Co2L4(H2O)2]·CH3CN·H2O (HL = (E)-2-[2-(4-chlorophenyl)vinyl]-8-hydroxyquinoline) has been achieved with 95% yield by using an Asia flow synthesis system (chip reactor). Compared with the conventional batch-type methods such as diffusion, reflux and solvothermal reactions, higher yielding reactions carried out in a flow reactor have demonstrated that this technique is a powerful strategy to obtain coordination compounds.

  15. Size-tunable fabrication of multifunctional Bi2O3 porous nanospheres for photocatalysis, bacteria inactivation and template-synthesis.

    Science.gov (United States)

    Qin, Fan; Zhao, Huiping; Li, Guangfang; Yang, Hao; Li, Ju; Wang, Runming; Liu, Yunling; Hu, Juncheng; Sun, Hongzhe; Chen, Rong

    2014-05-21

    Multifunctional Bi2O3 porous nanospheres (PNs) with tunable size have been successfully synthesized via a facile solvothermal method. The obtained Bi2O3 porous nanospheres demonstrate outstanding performance in visible-light-driven photocatalysis for Cr(VI) and organic dye removal, inactivation of Gram-negative and Gram-positive bacteria, as well as template-synthesis for fabrication of bismuth-related hollow nanostructures.

  16. Eosinophilic Enterocolitis: An Exceedingly Rare Entity

    Directory of Open Access Journals (Sweden)

    Richard José Lopes Azevedo

    2017-11-01

    Full Text Available Eosinophilic enterocolitis is an exceptionally rare condition with few described cases in the literature, representing the least frequent manifestation of the wide spectrum of eosinophilic gastrointestinal disorders. We describe a case of a young male patient presenting with a panmural form of the disease, manifested by abdominal pain, distention, and watery diarrhea with 4 days of evolution, bowel wall thickening, and ascites. Eosinophilic ascites is probably the most unusual presentation form of this entity. It poses a diagnostic challenge because of its nonspecific symptoms, associated with the absence of standardized histological criteria, hence requiring a high level of suspicion. There is also no consensus regarding treatment: it should be individualized according to the patient's age and severity of symptoms.

  17. Arabic medical entity tagging using distant learning

    Directory of Open Access Journals (Sweden)

    Viviana Cotik

    2017-04-01

    Full Text Available A semantic tagger aiming to detect relevant entities in Arabic medical documents and tagging them with their appropriate semantic class is presented. The system takes profit of a Multilingual Framework covering four languages (Arabic, English, French, and Spanish, in a way that resources available for each language can be used to improve the results of the others, this is specially important for less resourced languages as Arabic. The approach has been evaluated against Wikipedia pages of the four languages belonging to the medical domain. The core of the system is the definition of a base tagset consisting of the three most represented classes in SNOMED-CT taxonomy and the learning of a binary classifier for each semantic category in the tagset and each language, using a distant learning approach over three widely used knowledge resources, namely Wikipedia, Dbpedia, and SNOMED-CT.

  18. Primary gingival tuberculosis: A rare clinical entity

    Directory of Open Access Journals (Sweden)

    Geeti Gupta

    2011-01-01

    Full Text Available Tuberculosis is a specific granulomatous infectious disease and a major cause of death in developing countries. Primary gingival tuberculosis is extremely rare and forgotten entity. Oral lesions usually appear as secondary to primary tuberculosis infection elsewhere. The lesion may take the form of nodules, ulcers, or elevated fissures. We report a case of primary tuberculosis of gingiva, manifesting as gingival enlargement with ulceration and discharge. Diagnosis was based on histopathologic examination, complete blood count, chest X-ray, and immunologic investigations with detection of antibodies against Mycobacterium tuberculosis. With the recent increase in the incidence of tuberculosis, this case report also emphasizes the need for clinicians to be aware of this possibility, consider tuberculosis in the differential diagnosis of gingival enlargement, and thus, play a role in the early detection of this disease.

  19. FISCAL POLICY OF THE REPUBLIC OF MOLDOVA: ACHIEVEMENTS OF THE FISCAL CONTROL AND ENTITY BEHAVIOR

    Directory of Open Access Journals (Sweden)

    Olimpiu GHERMAN

    2015-12-01

    Full Text Available It is an actual theme, determined by achievements of tax control in Moldova and its impact on the behaviour of the entity as important elements of fiscal policy. There are examined different methods for differentiating the problem, supplemented by deduction, induction, synthesis, analysis of defining phenomena of fiscal policy and its elements. The methodology used in this study is based on assessments of the theory, studies and interpretations of specialized literature and analyzes the practical activities specific for taxation at national, European and international levels, depending on which some opinions, conclusions and proposals were founded and formulated, to minimize the impact of tax evasion and fraud.

  20. Entity Resolution Workflow Installation Process and User Guide

    Science.gov (United States)

    2013-07-01

    with an entity extractor called English Information Extractor (ENIE) developed by City University of New York’s (CUNY) BLENDER lab‡. The user is not...CUNY BLENDER . http://nlp.cs.qc.cuny.edu/ (accessed June 2013). 2 alternate entity extractor. Another entity extractor called A Nearly-New...is now installed and ready to use. Please see the section 6 to learn how to use the ERW Web application. 6. ERW Web Application User Guide The ERW

  1. Discrimination of legal entities: Phenomenological characteristics and legal protection

    Directory of Open Access Journals (Sweden)

    Petrušić Nevena

    2017-01-01

    Full Text Available Their social nature encourages people to associate and jointly achieve the goals that they would not be able to achieve individually. Legal entities are created as one of the legal modalities of that association, as separate entities that have their own legal personality independent of the subjectivity of their members. Legal entities are holders of some human rights, depending on the nature of the right, including the right to non-discrimination. All mechanisms envisaged for legal protection against discrimination in the national legislation are available to legal persons. On the other hand, the situation is quite different in terms of access to international forums competent to deal with cases of discrimination. Legal entities do not have access to some international forums, while they may have access to others under the same conditions prescribed for natural persons. Legal entities may be exposed to various forms of direct and indirect discrimination both in the private and in the public sphere of social relations. Phenomenological characteristics of discrimination against legal persons are not substantially different from discrimination against individuals. There are no significant differences regarding the application of discrimination test in cases of discrimination of legal entities as compared to the use of this test in cases involving discrimination of natural persons or groups of persons. Legal entities may be discriminated against on the basis of characteristics of their legal personality, such as those which are objective elements of the legal entity and part of its legal identity. Discrimination of legal entities may be based on personal characteristics of its members (i.e. people who make a personal essence of a legal entity because their characteristics can be 'transferred' to the legal entity and become part of its identity. Legal entities should also be protected from this special form of transferred (associative discrimination.

  2. Context and Domain Knowledge Enhanced Entity Spotting in Informal Text

    Science.gov (United States)

    Gruhl, Daniel; Nagarajan, Meena; Pieper, Jan; Robson, Christine; Sheth, Amit

    This paper explores the application of restricted relationship graphs (RDF) and statistical NLP techniques to improve named entity annotation in challenging Informal English domains. We validate our approach using on-line forums discussing popular music. Named entity annotation is particularly difficult in this domain because it is characterized by a large number of ambiguous entities, such as the Madonna album "Music" or Lilly Allen's pop hit "Smile".

  3. Entity Recognition Via Multimodal Sensor Fusion With Smart Phones

    Science.gov (United States)

    2015-03-26

    being measured by the smart phone sensors. The American Heritage College Dictionary defines entity to be ”the ex- istence of something considered...ENTITY RECOGNITION VIA MULTIMODAL SENSOR FUSION WITH SMART PHONES THESIS John E. Nagy, Capt, USAF AFIT-ENG-MS-15-M-023 DEPARTMENT OF THE AIR FORCE...subject to copyright protection in the United States. AFIT-ENG-MS-15-M-023 ENTITY RECOGNITION VIA MULTIMODAL SENSOR FUSION WITH SMART PHONES THESIS

  4. WCF multi-layer services development with Entity framework

    CERN Document Server

    Liu, Mike

    2014-01-01

    If you are a C#, VB.NET, or C++ developer and want to get started with WCF and Entity Framework, then this book is for you. Competence in Entity Framework will be needed to follow the examples in the book, but experience in creating WCF services using Entity Framework is not necessary. Developers and architects evaluating SOA implementation technologies for their company will find this book useful.

  5. System for Award Management (SAM) Public Extract - Entity Registration

    Data.gov (United States)

    General Services Administration — This dataset contains the information available under the Freedom of Information Act (FOIA) for those entities registered to do business with the Federal government...

  6. Citrate-free synthesis of silver nanoplates and the mechanistic study.

    Science.gov (United States)

    Zhang, Qiang; Yang, Yin; Li, Jonathan; Iurilli, Raymond; Xie, Shuifen; Qin, Dong

    2013-07-10

    We report a citrate-free synthesis of Ag nanoplates with an edge length of 50 nm that involved the reduction of AgNO3 by poly(vinyl pyrrolidone) (PVP) in ethanol at 80 °C under a solvothermal condition. Within a period of 4 h, greater than 99% of the initially added AgNO3 could be converted into Ag nanoplates with excellent stability. To understand this remarkably simple and efficient process, we systematically investigated the roles played by various reaction parameters, which include the type of precursor, reducing powers of PVP and ethanol, molar ratio of PVP to AgNO3, solvent, involvement of O2, and effects of pressure and temperature. Our results suggest a plausible mechanism that involves (i) fast reduction of AgNO3 to generate Ag multiple twinned particles (MTPs) via a thermodynamically controlled process, (ii) kinetically controlled formation of plate-like seeds and their further growth into small nanoplates in the presence of Ag(+) ions at a low concentration, and (iii) complete transfer of Ag atoms from the MPTs to nanoplates via O2-mediated Ostwald ripening. We demonstrated that the molar ratio of PVP to AgNO3 in ethanol plays an essential role in controlling the reduction rate for the formation of MTPs and plate-like seeds under the solvothermal condition, transformation kinetics, and final morphology taken by the Ag nanoplates. In particular, when the reaction temperatures were above the boiling point of ethanol, the pressure induced by a solvothermal process accelerated the oxidative etching of Ag MTPs to facilitate their complete conversion into nanoplates. The mechanistic insight could serve as a guideline to optimize the experimental parameters of a solvothermal synthesis to control the reduction kinetics and thus the formation of metallic nanocrystals with controlled shapes and in high yields and large quantities.

  7. Antimony Nanocrystals Encapsulated in Carbon Microspheres Synthesized by a Facile Self-Catalyzing Solvothermal Method for High-Performance Sodium-Ion Battery Anodes.

    Science.gov (United States)

    Qiu, Shen; Wu, Xianyong; Xiao, Lifen; Ai, Xinping; Yang, Hanxi; Cao, Yuliang

    2016-01-20

    Antimony/carbon (Sb@C) microspheres are initially synthesized via a facile self-catalyzing solvothermal method, and their applicability as anode materials for sodium-ion batteries is investigated. The structural and morphological characterizations reveal that Sb@C microspheres are composed of Sb nanoparticles (∼20 nm) homogeneously encapsulated in the C matrix. The self-catalyzing solvothermal mechanism is verified through comparative experiments by using different raw materials. The as-prepared Sb@C microspheres exhibit superior sodium storage properties, demonstrating a reversible capacity of 640 mAh g(-1), excellent rate performance, and an extended cycling stability of 92.3% capacity retention over 300 cycles, making them promising anode materials for sodium-ion batteries.

  8. Morphology and non-isothermal crystallization kinetics of CuInS{sub 2} nanocrystals synthesized by solvo-thermal method

    Energy Technology Data Exchange (ETDEWEB)

    Majeed Khan, M.A., E-mail: majeed_phys@yahoo.co.in [King Abdullah Institute for Nanotechnology, King Saud University, Riyadh 11451 (Saudi Arabia); Kumar, Sushil [Department of Physics, Chaudhary Devi Lal University, Sirsa 125055 (India); Alsalhi, M.S. [King Abdullah Institute for Nanotechnology, King Saud University, Riyadh 11451 (Saudi Arabia); Department of Physics and Astronomy, King Saud University, Riyadh 11451 (Saudi Arabia); Ahamed, Maqusood [King Abdullah Institute for Nanotechnology, King Saud University, Riyadh 11451 (Saudi Arabia); Alhoshan, Mansour [King Abdullah Institute for Nanotechnology, King Saud University, Riyadh 11451 (Saudi Arabia); Chemical Engineering Department, King Saud University, Riyadh 11451 (Saudi Arabia); Alrokayan, Salman A. [King Abdullah Institute for Nanotechnology, King Saud University, Riyadh 11451 (Saudi Arabia); Ahamad, Tansir [Department of Chemistry, King Saud University, Riyadh 11451 (Saudi Arabia)

    2012-03-15

    Nanocrystals of copper indium disulphide (CuInS{sub 2}) were synthesized by a solvo-thermal method. The structure, morphology and non-isothermal crystallization kinetic behavior of samples were investigated using X-ray diffraction, field emission scanning electron microscopy, field emission transmission electron microscopy, thermogravimetric analysis and differential thermal analysis techniques. Non-isothermal measurements at different heating rates were carried out and the crystallization kinetics of samples were analyzed using the most reliable non-isothermal kinetic methods. The kinetic parameters such as glass transition temperature, thermal stability, activation energy, Avrami exponent etc. were evaluated. - Highlights: Black-Right-Pointing-Pointer CuInS{sub 2} nanocrystals have scientific and technological importance. Black-Right-Pointing-Pointer Samples have been prepared by solvo-thermal method. Black-Right-Pointing-Pointer Synthesized samples exhibit excellent morphology and thermal properties. Black-Right-Pointing-Pointer Investigated properties may be utilized in design and fabrication of solar cell devices.

  9. Building entity models through observation and learning

    Science.gov (United States)

    Garcia, Richard; Kania, Robert; Fields, MaryAnne; Barnes, Laura

    2011-05-01

    To support the missions and tasks of mixed robotic/human teams, future robotic systems will need to adapt to the dynamic behavior of both teammates and opponents. One of the basic elements of this adaptation is the ability to exploit both long and short-term temporal data. This adaptation allows robotic systems to predict/anticipate, as well as influence, future behavior for both opponents and teammates and will afford the system the ability to adjust its own behavior in order to optimize its ability to achieve the mission goals. This work is a preliminary step in the effort to develop online entity behavior models through a combination of learning techniques and observations. As knowledge is extracted from the system through sensor and temporal feedback, agents within the multi-agent system attempt to develop and exploit a basic movement model of an opponent. For the purpose of this work, extraction and exploitation is performed through the use of a discretized two-dimensional game. The game consists of a predetermined number of sentries attempting to keep an unknown intruder agent from penetrating their territory. The sentries utilize temporal data coupled with past opponent observations to hypothesize the probable locations of the opponent and thus optimize their guarding locations.

  10. Inflammatory breast carcinoma: pathological or clinical entity?

    Science.gov (United States)

    Amparo, R S; Angel, C D; Ana, L H; Antonio, L C; Vicente, M S; Carlos, F M; Vicente, G P

    2000-12-01

    Inflammatory breast carcinoma (IBC) diagnosis is usually based in the presence of typical clinical symptoms (redness and edema in more than 2/3 of the breast), which are not always associated with pathologic characteristics (subdermal lymphatics involvement). Whether exclusively pathologic findings without clinical symptoms are sufficient for IBC diagnosis remains controversial. A retrospective analysis of 163 clinically diagnosed IBC (CIC) either with dermal lymphatics invasion or not, was compared with another group of 99 patients with dermal lymphatics invasion without clinical symptoms (occult inflammatory carcinoma) (OIC). The following clinical and pathological characteristics have been analyzed and compared: age, menopausal status, clinical axillar node involvement, symptoms duration before diagnosis, grade, estrogen receptors, presence of metastases at diagnosis, local recurrence, metastasic dissemination, disease-free (DFS) and overall survival (OS). Median age was younger in CIC (52.3 vs. 63.8 years; p metastases (7.4% vs. 1%; p = 0.02) was significantly more frequent in CIC. Negative estrogen receptors were more frequent in CIC (34.9% vs. 65.1%: p < 0.004). Five-years DFS (25.6 vs. 51.6%; p < 0.0001) and OS (28.6 vs. 40%; p < 0.05) were shorter in CIC. CIC (regardless of subdermal lymphatics involvement) must be clearly differentiated from OIC. Prognosis of CIC patients is poorer, so this two entities should be clearly differentiated when therepeutic results are reported.

  11. Abstract Modelling of the Impact of Activities of Economic Entities on the Social System

    Directory of Open Access Journals (Sweden)

    Dana Bernardová

    2017-01-01

    Full Text Available Economic entities as integral parts of the social system have an impact on it. The complexity of structures and uncertainty of behaviour which are also conditioned by incorporating the human factor are the typical characteristics of economic entities and the social system. The lack of precise measurement data as well as precise information is their typical feature. Methods of creating computer models of such systems must therefore be based on uncertain, incomplete or approximate data and hypothetical assumptions. The paper deals with the synthesis of the abstract model of the expert system for determining the level of corporate social responsibility of an enterprise (CSR with the use of methods of artificial intelligence. The linguistic rule model is built on the basis of the expert determination of the level of CSR based on the level of care for employees, level of supplier‑customer relations, level of its ecological behaviour, and compliance with legal obligations. The linguistic modelling method is based on the theoretical approach to fuzzy set mathematics and fuzzy logic. The aim of the paper is the presentation of the system for determining the level of CSR with the use of non‑conventional non‑numerical methods as well as simulative presentation of the efficiency of its functions. The above‑mentioned expert system is a relevant module of the built hierarchical structure aimed at the research of impacts of activities of economic entities on the social system.

  12. Preparation of weak-light-driven TiO2-based catalysts via adsorbed-layer nanoreactor synthesis and enhancement of their photo-degradation performance in seawater

    Science.gov (United States)

    Wang, Ting; Xu, Zhi-yong; Zhu, Yi-chen; Wu, Li-guang; Yuan, Hao-xuan; Li, Chang-chun; Liu, Ya-yu; Cai, Jing

    2017-11-01

    Graphene oxide (GO) was first employed as a support in preparing TiO2 nanoparticles by adsorbed-layer nanoreactor synthesis (ALNS). Both TiO2 crystallization and GO reduction simultaneously occurred during solvothermal treatment with alcohol as a solvent. By transmission electron microscopy, high resolution transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, and photoluminescence spectroscopy, the results showed that TiO2 nanoparticles with less than 10 nm of size distributed very homogeneously on the GO surface. Tight interaction between TiO2 particles and GO surface could effectively inhibit the aggregation of TiO2 particles, during solvothermal treatment for anatase TiO2 formation. Alcohol could also reduce oxygenated functional groups on GO surface after solvothermal treatment. TiO2 particles with small size and the decrease in oxygenated functional groups on the GO surface both caused high separation efficiency of photo-generated charge carriers, thus resulting in high photo-degradation performance of catalysts. Strong phenol adsorption on photocatalyst was key to enhancing photo-degradation efficiency for phenol in seawater. Moreover, the change in catalyst structure was minimal at different temperatures of solvothermal treatment. But, the degradation rate and efficiency for phenol in seawater were obviously enhanced because of the sensitive structure-activity relationship of catalysts under weak-light irradiation.

  13. A strategy of combining SILAR with solvothermal process for In{sub 2}S{sub 3} sensitized quantum dot-sensitized solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Peizhi, E-mail: pzhyang@hotmail.com [Key Laboratory of Advanced Technique & Preparation for Renewable Energy Materials, Ministry of Education, Yunnan Normal University, Kunming 650500 (China); Tang, Qunwei, E-mail: tangqunwei@ouc.edu.cn [Institute of Materials Science and Engineering, Ocean University of China, Qingdao 266100 (China); Ji, Chenming; Wang, Haobo [Institute of Materials Science and Engineering, Ocean University of China, Qingdao 266100 (China)

    2015-12-01

    Graphical abstract: - Highlights: • In{sub 2}S{sub 3} sensitized TiO{sub 2} anode is prepared by combining SILAR with solvothermal process. • The deposition cycle in SILAR process has an impact on cell performances. • A promising conversion efficiency of 1.39% is obtained for the optimal device. • The cell performances are markedly increased compared with SILAR technique. - Abstract: Pursuit of an efficient strategy for quantum dot-sensitized photoanode has been a persistent objective for enhancing photovoltaic performances of quantum dot-sensitized solar cell (QDSC). We present here the fabrication of the indium sulfide (In{sub 2}S{sub 3}) quantum dot-sensitized titanium dioxide (TiO{sub 2}) photoanode by combining successive ionic layer adsorption and reaction (SILAR) with solvothermal processes. The resultant QDSC consists of an In{sub 2}S{sub 3} sensitized TiO{sub 2} photoanode, a liquid polysulfide electrolyte, and a Co{sub 0.85}Se counter electrode. The optimized QDSC with photoanode prepared with the help of a SILAR method at 20 deposition cycles and solvothermal method yields a maximum power conversion efficiency of 1.39%.

  14. Facile consecutive solvothermal growth of highly fluorescent InP/ZnS core/shell quantum dots using a safer phosphorus source.

    Science.gov (United States)

    Byun, Ho-June; Song, Woo-Seuk; Yang, Heesun

    2011-06-10

    The work presents a facile, stepwise synthetic approach for the production of highly fluorescent InP/ZnS core/shell quantum dots (QDs) by using a safer phosphorus (P) precursor. First, InP quantum dots (QDs) were solvothermally prepared at 180 °C for 24 h by using a P source of P(N(CH(3))(2))(3). The as-grown InP QDs were consecutively placed in another solvothermal condition for ZnS shell overcoating. In contrast to the almost non-fluorescent InP QDs, due to their highly defective surface states, the ZnS-coated InP QDs were highly fluorescent as a result of effective surface passivation. After the shell growth, the resulting InP/ZnS core/shell QDs were subjected to a size-sorting processing, by which red- to green-emitting QDs with quantum yields (QYs) of 24-60% were produced. Solvothermal shell growth parameters such as the reaction time and Zn/In solution concentration ratio were varied and optimized toward the highest QYs of core/shell QDs.

  15. 78 FR 45051 - Unincorporated Business Entities; Effective Date

    Science.gov (United States)

    2013-07-26

    ... institutions' use of unincorporated business entities organized under State law for certain business activities... business entities (UBEs) organized under State law for certain business activities. A UBE includes limited... business trusts, organized under State law. The final rule does not apply to UBEs that one or more System...

  16. When Depression Mediates the Relationship between Entity Beliefs and Performance

    Science.gov (United States)

    Da Fonseca, David; Cury, Francois; Santos, Andreia; Payen, Vincent; Bounoua, Lenda; Brisswalter, Jeannick; Rufo, Marcel; Poinso, Francois; Deruelle, Christine

    2009-01-01

    The aim of this study was to determine whether depression can explain the negative relationship between academic performance and the belief that intelligence is a fixed trait, i.e., entity belief. A sample of 353 French volunteer adolescents (age 11-16) completed questionnaires assessing entity theory and depressive symptoms (Children Depression…

  17. A generic open world named entity disambiguation approach for tweets

    NARCIS (Netherlands)

    Habib, Mena Badieh; van Keulen, Maurice

    Social media is a rich source of information. To make use of this information, it is sometimes required to extract and disambiguate named entities. In this paper we focus on named entity disambiguation (NED) in twitter messages. NED in tweets is challenging in two ways. First, the limited length of

  18. 77 FR 60948 - Stress Testing of Regulated Entities

    Science.gov (United States)

    2012-10-05

    ... help it to assess capital adequacy under various scenarios at the regulated entities. Section 165(i)(2... the potential impact of different scenarios on their consolidated earnings and capital, and other..., forward-looking information that will help them to assess capital adequacy at the regulated entities under...

  19. 43 CFR 426.8 - Nonresident aliens and foreign entities.

    Science.gov (United States)

    2010-10-01

    ... 43 Public Lands: Interior 1 2010-10-01 2010-10-01 false Nonresident aliens and foreign entities..., DEPARTMENT OF THE INTERIOR ACREAGE LIMITATION RULES AND REGULATIONS § 426.8 Nonresident aliens and foreign... reclamation law or these regulations, a nonresident alien or foreign entity that directly holds land in a...

  20. Named entity recognition in a South African context

    CSIR Research Space (South Africa)

    De Waal, AJ

    2006-10-01

    Full Text Available Named Entity Recognition (NER) is the process of identifying occurrences of words or expressions as belonging to a particular category of a Named Entity (NE).The aim of the project was to test the feasibility of a probabilistic NER system using...

  1. Landmarks in motion : Unstable entities in route directions

    NARCIS (Netherlands)

    Baltaretu, Adriana-Alexandra; Krahmer, Emiel; Maes, Alfons; Noelle, D.C.; Dale, R.; Warlaumont, A.S.; Yoshimi, J.; Matlock, T.; Jennings, C.D.; Maglio, P.P.

    2015-01-01

    In the present study, we investigate if speakers refer to moving entities in route directions (RDs). On the one hand, there is a general agreement that landmarks are perceptually salient and stable objects. On the other hand, animated movement attracts visual attention, making entities intrinsically

  2. How Well can We Learn Interpretable Entity Types from Text?

    DEFF Research Database (Denmark)

    Hovy, Dirk

    2014-01-01

    We investigate a largely unsupervised approach to learning interpretable, domain-specific entity types from unlabeled text. It assumes that any common noun in a domain can function as potential entity type, and uses those nouns as hidden variables in a HMM. To constrain training, it extracts co-o...... an informed baseline, reducing the error rate by 56%....

  3. Combining Document-and Paragraph-Based Entity Ranking

    NARCIS (Netherlands)

    Rode, H.; Serdyukov, Pavel; Hiemstra, Djoerd

    2008-01-01

    We study entity ranking on the INEX entity track and pro- pose a simple graph-based ranking approach that enables to combine scores on document and paragraph level. The com- bined approach improves the retrieval results not only on the INEX testset, but similarly on TREC’s expert finding task.

  4. 14 CFR Sec. 1-6 - Accounting entities.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Accounting entities. Sec. 1-6 Section 1-6... REGULATIONS UNIFORM SYSTEM OF ACCOUNTS AND REPORTS FOR LARGE CERTIFICATED AIR CARRIERS General Accounting Provisions Sec. 1-6 Accounting entities. (a) Separate accounting records shall be maintained for each air...

  5. 7 CFR 25.401 - Responsibility of lead managing entity.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 1 2010-01-01 2010-01-01 false Responsibility of lead managing entity. 25.401 Section... COMMUNITIES Post-Designation Requirements § 25.401 Responsibility of lead managing entity. (a) Financial. The... fiscal management of the funds of the Empowerment Zone or Enterprise Community. (b) Reporting. The lead...

  6. 42 CFR 438.808 - Exclusion of entities.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 4 2010-10-01 2010-10-01 false Exclusion of entities. 438.808 Section 438.808... Exclusion of entities. (a) General rule. FFP is available in payments under MCO contracts only if the State..., directly or indirectly, for the furnishing of health care, utilization review, medical social work, or...

  7. 78 FR 22270 - Special Fraud Alert: Physician-Owned Entities

    Science.gov (United States)

    2013-04-15

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF HEALTH AND HUMAN SERVICES Office of Inspector General Special Fraud Alert: Physician-Owned Entities AGENCY: Office... issued Special Fraud Alert on Physician-Owned Entities. Specifically, the Special Fraud Alert addressed...

  8. Interactive Exploration of Co-evolving Software Entities

    NARCIS (Netherlands)

    Vanya, A.; Premraj, R.; van Vliet, H.

    2010-01-01

    Frequent changes to groups of software entities belonging to different parts of the system may indicate structural issues in the system’s decomposition. An in-depth analysis of such groups of entities is needed to understand the underly- ing reasons for co-changes, and also determine how to resolve

  9. Effect of precursor concentration on the electrical properties of LiFePO4 prepared by solvothermal method

    Science.gov (United States)

    Rabbani, Ahmad Yasin; Fakhri, Hafizh A.; Arifin, Muhammad; Aimon, Akfiny Hasdi; Iskandar, Ferry

    2016-02-01

    Lithium iron phosphate (LiFePO4) is frequently used for Li-ion battery cathode. LiFePO4 has the high specific capacity at 170 mAhg-1, stable voltage at 3.45 V, stable structure, cheap, and low toxicity. The objective of this research is investigating the effect of precursor concentration on the electrical properties of LiFePO4 prepared by solvothermal method. LiOH, FeSO4, H3PO4, and citric acid were used as the precursors. The LiOH concentration was varied from 0.3 M to 1.8 M. The Fourier Transform Infrared Spectroscopy (FTIR) measurement identified the Fe-O, O-P-O, and P-O bonds which corresponding to LiFePO4. The result of 4-point probe measurement shows that, among the prepared samples, the sample from the precursor concentration of 1.8 M has the highest electrical conductivity.

  10. Pt nanoparticles supported over Ce-Ti-O: the solvothermal and photochemical approaches for the preparation of catalytic materials

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Adrian M. T., E-mail: adrian@fe.up.pt; Machado, Bruno F.; Gomes, Helder T.; Figueiredo, Jose L. [Universidade do Porto, Laboratorio de Catalise e Materiais (LCM), Laboratorio Associado LSRE/LCM, Departamento de Engenharia Quimica, Faculdade de Engenharia (Portugal); Drazic, Goran, E-mail: goran.drazic@ijs.s [Jozef Stefan Institute, Department of Nanostructured Materials (Slovenia); Faria, Joaquim L. [Universidade do Porto, Laboratorio de Catalise e Materiais (LCM), Laboratorio Associado LSRE/LCM, Departamento de Engenharia Quimica, Faculdade de Engenharia (Portugal)

    2010-01-15

    Ce-Ti-O supports with different Ce/Ti molar ratios were synthesized by the solvothermal method using hexadecyltrimethylammonium bromide. Pt nanoparticles were then supported by photochemical deposition. The shape, size, and structure of these materials were analyzed by high-resolution transmission electron microscopy. The single CeO{sub 2} support was also prepared, consisting of agglomerated cubic particles ranging from {approx}3 to 8 nm. When titania was combined with ceria, a nanostructured architecture was produced, evidencing the strong influence of Ti in the support structure. Photodeposition of Pt nanoparticles is more efficient on Ce-Ti-O supports than in pristine CeO{sub 2}. Crystalline Pt nanoparticles (mainly of {approx}2 to 4 nm) were detected. The catalytic properties of the materials were tested in the selective hydrogenation of cinnamaldehyde to cinnamyl alcohol. It was observed that Pt supported on Ce-Ti-O is more active and selective than Pt on CeO{sub 2} or TiO{sub 2} separately. The catalyst with 40 mol% Ce leads to total conversion of cinnamaldehyde in a few minutes; however, higher selectivity toward the desired product (cinnamyl alcohol) was obtained with higher amounts of Ce (50 mol%).

  11. Two polymorphs of cobalt(II) imidazolate polymers synthesized solvothermally by using one organic template N,N-dimethylacetamide.

    Science.gov (United States)

    Tian, Yun-Qi; Chen, Zhen-Xia; Weng, Lin-Hong; Guo, Hui-Bin; Gao, Song; Zhao, Dong Yuan

    2004-07-26

    Two structurally different polymorphs of cobalt(II) imidazolate frameworks are solvothermally synthesized by using N,N-dimethylacetamide as a template: The polymorph 6 (a = 9.797 (4) angstroms, b = 15.301(6) angstroms, c =14.902(6) angstroms, beta = 98.904(6) degrees, monoclinic, P21/n) shows structures of silicate CaAl2Si2O8 with CrB4 topology, while polymorph 7 (a = 15.173(4) angstroms, b = 15.173(4) angstroms, c = 19.089(5) angstroms, Pbca) shows CaGa2O4-related topological structures. In addition, the 7' (a = 15.9712(18) angstroms, b = 15.9253(19) angstroms, c = 18.475(2) angstroms, Pbca), a compound isostructural with 7, is synthesized by using cyclohexanol as a template. Thus, these cobalt(II) imidazolate polymers are reminiscent of the zeolite syntheses in that not only the same topological structure can be synthesized by using the different organic templates, but also different topological structures can be synthesized by using the same organic template. Copyright 2004 American Chemical Society

  12. An Experimental Study on the Shape Changes of TiO2 Nanocrystals Synthesized by Microemulsion-Solvothermal Method

    Directory of Open Access Journals (Sweden)

    Wei Kong

    2011-01-01

    Full Text Available Titanium dioxide (TiO2 nanocrystals of different shape were successfully synthesized in a new microemulsion system through a solvothermal process. The TiO2 nanocrystals were prepared from the reaction of tetrabutyl titanate (TBT, H2O, and oleic acid (OA, which were used as solvent and surfactant at 300∘C and 240∘C in a stainless steel autoclave. The sphere, polygon, and rhombus-shaped nanocrystals have been prepared at 300∘C and the dot- and- rod shaped nanocrystals have been synthesized at 240∘C. The effect of the reaction time on the shape and size of TiO2 nanocrystals in this method was studied in the present paper. The size distribution of TiO2 nanocrystals prepared at 300∘C for different hours is also studied. In addition, an attempt to describe the mechanism of shape change of TiO2 nanocrystals was presented in this paper.

  13. Magnetic and photocatalytic studies on Zn1-xMgxFe2O4 nanocolloids synthesized by solvothermal reflux method.

    Science.gov (United States)

    Manohar, A; Krishnamoorthi, C

    2017-12-01

    Biocompatible magnetic semiconductor Zn1-xMgxFe2O4 (x=0, 0.1, 0.3, 0.5 & 0.7) nanoparticles of around 10nm diameter were synthesized by solvothermal reflux method. The method produces well separated and narrow size distributed nanoparticles. Crystal structure, morphology, particles surface properties, surfactant quantity, colloidal stability, magnetic properties and photocatalytic properties of the synthesized nanoparticles were studied. Different characterizations confirmed that all compounds were single crystals and superparamagnetic at room temperature. Saturation mass magnetization (Ms=57.5emu/g) enhances with substituent Mg(2+) concentration due to promotion of mixed spinel (normal and inverse) structure. Photocatalytic activity of all synthesized magnetic semiconductor nanoparticles were studied through methylene blue degradation. The degradation of 98% methylene blue was observed on 60 min irradiation of light. It is observed that photocatalytic activity slightly enhances with substituent Mg(2+) concentration. The synthesized biocompatible magnetic semiconductor nanoparticles can be utilized as photocatalysts and could also be recycled and separated by applying an external magnetic field. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Rapid adsorption properties of flower-like BiOI nanoplates synthesized via a simple EG-assisted solvothermal process

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Bin; Ji, Guangbin, E-mail: gbji@nuaa.edu.cn [Nanjing University of Aeronautics and Astronautics, College of Materials Science and Technology (China); Gondal, M. A. [King Fahd University of Petroleum and Minerals, Physics Department (Saudi Arabia); Liu, Yousong; Zhang, Xingmiao; Chang, Xiaofeng; Li, Nianwu [Nanjing University of Aeronautics and Astronautics, College of Materials Science and Technology (China)

    2013-07-15

    Uniform well-crystallized flower-like BiOI nanoplates contained 3.7 nm mesopores, which may be attributed to the internanosheet spaces of BiOI with maximum pore diameters of about 30 nm, were successfully synthesized via a simple ethylene glycol-assisted solvothermal method. The as-prepared porous BiOI nanoplates exhibited excellent adsorption ability, and the saturated extent of adsorption of BiOI over an RhB solution was as high as 197 mg/g, which is much higher than those for BiOCl and BiOBr prepared via the same method and with a similar surface area. The probable adsorption mechanism could have originated from the interaction between the I atom in BiOI and a proton in RhB at different pH values and temperatures. With visible light irradiation ({lambda} > 420 nm), 80 % of the RhB was degraded in 4 h, while BiOI still demonstrated reasonably outstanding photocatalytic ability under green light ({lambda} = 550 {+-} 15 nm) because of its low-energy gap (1.72 eV). The degradation test for BiOI under irradiation at {lambda} = 550 {+-} 15 nm is an excellent achievement for field applications because the catalyst can be applied in solar irradiation to remove organic pollutants, which may be of great value BiOI complex.

  15. Oriented growth of magnetite along the carbon nanotubes via covalently bonded method in a simple solvothermal system

    Energy Technology Data Exchange (ETDEWEB)

    Zhan Yingqing; Zhao Rui; Meng Fanbing; Lei Yajie; Zhong Jiachun; Yang Xulin [Research Branch of Functional Materials, Institute of Microelectronic and Solid State Electronic, University of Electronic Science and Technology of China, Chengdu 610054 (China); Liu Xiaobo, E-mail: liuxb@uestc.edu.cn [Research Branch of Functional Materials, Institute of Microelectronic and Solid State Electronic, University of Electronic Science and Technology of China, Chengdu 610054 (China)

    2011-06-15

    Highlights: > Novel CNTs/magnetite hybrid materials were prepared via covalently bonded method. > Stable interaction between nitriles and iron ion promoted the oriented growth of magnetite. > The hybrid material exhibited higher magnetism and electromagnetic properties - Abstract: A new type of CNTs/magnetite hybrid material was prepared via covalently bonded method in a simple solvothermal system using FeCl{sub 3} as iron source, ethylene glycol as the reducing agent, and 4-aminophenoxyphthalonitrile-grafted CNTs as templates. The magnetite nanoparticles, with the diameters of 70-80 nm, were self-assembled along the CNTs. The FTIR, UV-vis and DSC revealed that a stable covalent bond between nitriles group and iron ion promoted the oriented growth of magnetite nanoparticles along the CNTs, resulting in good dispersibility and solution storage stability. The magnetic properties measurements indicated that a higher saturated magnetization (70.7 emu g{sup -1}) existed in the CNTs/magnetite hybrid material, which further enhanced the electromagnetic properties. The magnetic loss was caused mainly by natural resonance, which is in good agreement with the Kittel equation results. The novel electromagnetic hybrid material is believed to have potential applications in the microwave absorbing performances.

  16. Facet and morphology dependent photocatalytic hydrogen evolution with CdS nanoflowers using a novel mixed solvothermal strategy.

    Science.gov (United States)

    Liu, Yi; Ma, Yongjin; Liu, Wenwen; Shang, Yanyang; Zhu, Anquan; Tan, Pengfei; Xiong, Xiang; Pan, Jun

    2017-11-10

    As the highest energy facet of wurtzite CdS, (0 0 2) facet is well worth investigating toward the contribution in photocatalytic hydrogen (H 2 ) evolution. In this study, flower-like CdS with highly preferred (0 0 2) facet was fabricated through a low temperature mixed-solvothermal strategy. The mixted-solvent of diethylenetriamine (DETA) and ethyl alcohol (EtOH) was used to inhibit the growth of (1 0 0) and (1 0 1) facets. For comparison, porous flower-like, belt-like and net-like CdS samples with different preferred degrees of (0 0 2) facet were controllably synthesized by the addition of H 2 O in different proportions. The preferred orientation degrees of (0 0 2) facet were qualitative proved by the mathematical fitting of XRD patterns. As expected, the flower-like CdS exhibited the highest photocatalytic activity on H 2 evolution under visible light without any co-catalyst. Meanwhile, the photocatalytic H 2 production increased with the increasement of exposed (0 0 2) facet, which suggested that (0 0 2) facet of CdS played a critical role in improving the photocatalytic activity. Moreover, the growth mechanisms of CdS with various morphologies were investigated and proposed in detail. Copyright © 2017. Published by Elsevier Inc.

  17. Investigating the effect of solvents for the preparation of CuSbS2 nanoparticles by solvothermal method

    Science.gov (United States)

    John, Bincy; Silvena, G. Genifer; Rajesh, A. Leo

    2017-05-01

    High quality ternary CuSbS2 nanoparticles with orthorhombic structure and controllable morphologies were successfully synthesized using a facile solvothermal method. To prepare these particles, ethylene glycol and ethylenediamine were used as solvents and Polyvinylpyrrolidone (PVP) as a structure directing ligand. Structural and morphological studies revealed that CuSbS2 nanoparticles prepared using PVP as surfactant and ethylene glycol as solvent produced a phase pure, controllable size and shaped nanoparticles. The electrical conductivity of the CuSbS2 pellets varied from 3.0987 × 10-2 to 9.103 × 10-2 S cm-1. Optical properties showed broad absorption in the visible region for all the samples and the estimated absorption band gap were found to vary from 1.11 eV to 1.42 eV whereas, analysis of fluorescence emission spectra provided the emission band gap of 1.59 eV. In both spectra, the results indicate that CuSbS2 nanomaterials have an optimum band gap energy which discloses the suitability for photovoltaic application.

  18. Raman Spectroscopy of Two-Dimensional Bi2TexSe3 − x Platelets Produced by Solvothermal Method

    Directory of Open Access Journals (Sweden)

    Jian Yuan

    2015-08-01

    Full Text Available In this paper, we report a facile solvothermal method to produce both binary and ternary compounds of bismuth chalcogenides in the form of Bi2TexSe3 − x. The crystal morphology in terms of geometry and thickness as well as the stoichiometric ratio can be well controlled, which offers the opportunities to systematically investigate the relationship between microstructure and phonon scattering by Raman spectroscopy. Raman spectra of four compounds, i.e., Bi2Se3, Bi2Se2Te, Bi2SeTe2 and Bi2Te3, were collected at four different excitation photon energies (2.54, 2.41, 1.96, and 1.58 eV. It is found that the vibrational modes are shifted to higher frequency with more Se incorporation towards the replacement of Te. The dependence of Raman vibrational modes on excitation photon energy was investigated. As the excitation photon energy increases, three Raman vibrational modes (A1g1, Eg2 and A1g2 of the as-produced compounds move to low frequency. Three Infrared-active (IR-active modes were observed in thin topological insulators (TIs crystals.

  19. Related Entity Finding: University of Waterloo at TREC 2010 Entity Track

    Science.gov (United States)

    2010-11-01

    contiguous   ngrams  from  the  “entity  name”  and       “narrative”  sections  of  the  topic.     Sort   ngrams  in...the  descending  order  of  the  number  of  words     For  each   ngram  n   If  n  OR  possessive  form  of

  20. 76 FR 63184 - Addition of Certain Persons on the Entity List; Implementation of Entity List Annual Review...

    Science.gov (United States)

    2011-10-12

    ... two persons to the Entity List: Hong Kong 1. Cho-Man Wong, Room 2608, Technology Plaza, 29-35 Sha Tsui Road, Tsuen Wan, Hong Kong; and 2. Hang Tat Electronics Enterprises Co., Room 2608, Technology Plaza, 29-35 Sha Tsui Road, Tsuen Wan, Hong Kong. Removals From the Entity List This rule removes four...

  1. One-step synthesis of hierarchically porous hybrid TiO2 hollow spheres with high photocatalytic activity

    Science.gov (United States)

    Liu, Ruiping; Ren, Feng; Yang, Jinlin; Su, Weiming; Sun, Zhiming; Zhang, Lei; Wang, Chang-an

    2016-03-01

    Hierarchically porous hybrid TiO2 hollow spheres were solvothermally synthesized successfully by using tetrabutyl titanate as titanium precursor and hydrated metal sulfates as soft templates. The as-prepared TiO2 spheres with hierarchically pore structures and high specific surface area and pore volume consisted of highly crystallized anatase TiO2 nanocrystals hybridized with a small amount of metal oxide from the hydrated sulfate. The proposed hydrated-sulfate assisted solvothermal (HAS) synthesis strategy was demonstrated to be widely applicable to various systems. Evaluation of the hybrid TiO2 hollow spheres for the photo-decomposition of methyl orange (MO) under visible-light irradiation revealed that they exhibited excellent photocatalytic activity and durability.

  2. Deep learning with word embeddings improves biomedical named entity recognition.

    Science.gov (United States)

    Habibi, Maryam; Weber, Leon; Neves, Mariana; Wiegandt, David Luis; Leser, Ulf

    2017-07-15

    Text mining has become an important tool for biomedical research. The most fundamental text-mining task is the recognition of biomedical named entities (NER), such as genes, chemicals and diseases. Current NER methods rely on pre-defined features which try to capture the specific surface properties of entity types, properties of the typical local context, background knowledge, and linguistic information. State-of-the-art tools are entity-specific, as dictionaries and empirically optimal feature sets differ between entity types, which makes their development costly. Furthermore, features are often optimized for a specific gold standard corpus, which makes extrapolation of quality measures difficult. We show that a completely generic method based on deep learning and statistical word embeddings [called long short-term memory network-conditional random field (LSTM-CRF)] outperforms state-of-the-art entity-specific NER tools, and often by a large margin. To this end, we compared the performance of LSTM-CRF on 33 data sets covering five different entity classes with that of best-of-class NER tools and an entity-agnostic CRF implementation. On average, F1-score of LSTM-CRF is 5% above that of the baselines, mostly due to a sharp increase in recall. The source code for LSTM-CRF is available at https://github.com/glample/tagger and the links to the corpora are available at https://corposaurus.github.io/corpora/ . habibima@informatik.hu-berlin.de.

  3. BDDCS Class Prediction for New Molecular Entities

    Science.gov (United States)

    Broccatelli, Fabio; Cruciani, Gabriele; Benet, Leslie Z.; Oprea, Tudor I.

    2012-01-01

    The Biopharmaceutics Drug Disposition Classification System (BDDCS) was successfully employed for predicting drug-drug interactions (DDIs) with respect to drug metabolizing enzymes (DMEs), drug transporters and their interplay. The major assumption of BDDCS is that the extent of metabolism (EoM) predicts high versus low intestinal permeability rate, and vice versa, at least when uptake transporters or paracellular transport are not involved. We recently published a collection of over 900 marketed drugs classified for BDDCS. We suggest that a reliable model for predicting BDDCS class, integrated with in vitro assays, could anticipate disposition and potential DDIs of new molecular entities (NMEs). Here we describe a computational procedure for predicting BDDCS class from molecular structures. The model was trained on a set of 300 oral drugs, and validated on an external set of 379 oral drugs, using 17 descriptors calculated or derived from the VolSurf+ software. For each molecule, a probability of BDDCS class membership was given, based on predicted EoM, FDA solubility (FDAS) and their confidence scores. The accuracy in predicting FDAS was 78% in training and 77% in validation, while for EoM prediction the accuracy was 82% in training and 79% in external validation. The actual BDDCS class corresponded to the highest ranked calculated class for 55% of the validation molecules, and it was within the top two ranked more than 92% of the times. The unbalanced stratification of the dataset didn’t affect the prediction, which showed highest accuracy in predicting classes 2 and 3 with respect to the most populated class 1. For class 4 drugs a general lack of predictability was observed. A linear discriminant analysis (LDA) confirmed the degree of accuracy for the prediction of the different BDDCS classes is tied to the structure of the dataset. This model could routinely be used in early drug discovery to prioritize in vitro tests for NMEs (e.g., affinity to transporters

  4. CONSIDERATION REGARDING CURRENT ASSETS IN THE CONSTRUCTION ENTITIES

    Directory of Open Access Journals (Sweden)

    Laura Adriana COJOCARU (ALIONESCU

    2014-06-01

    Full Text Available Accounting for current assets mainly aims to obtain useful information on the management of their best in order to make management decisions. Counting efficiency of these assets, their importance, provides improved performance of the entity. In this paper we want to study the degree of implementation of policies and accounting treatments on the current assets in the specific construction economic entities, the problems of implementation and thus better addressing their theoretical and procedural to improve the information provided by financial statements. Due to the importance of proper conduct of business owned entities, accounting current assets should result in optimal and efficient control of current assets.

  5. Employee turnover and productivity among small business entities in Nigeria

    Directory of Open Access Journals (Sweden)

    John N. N. Ugoani

    2016-12-01

    Full Text Available This study was designed to evaluate the problems of employee turnover on productivity among small business entities in Nigeria, and recommend remedial actions. Employee turnover is the separation of employees from employers and replacement with other employees. Productive manpower is a critical element for the economic survival of any small business entity. The survey research design was used for the study. The sample comprised of 320 respondents. Data generated were analyzed by using descriptive, and Z-test statistical techniques. It was found that employee turnover adversely affects productivity in small business entities.

  6. Concrete Security for Entity Recognition: The Jane Doe Protocol

    DEFF Research Database (Denmark)

    Lucks, Stefan; Zenner, Erik; Weimerskirch, Andre

    2008-01-01

    Entity recognition does not ask whether the message is from some entity X, just whether a message is from the same entity as a previous message. This turns turns out to be very useful for low-end devices. The current paper proposes a new protocol – the “Jane Doe Protocol” –, and provides a formal...... proof of its concrete security. The protocol neither employs asymmetric cryptography, nor a trusted third party, nor any key pre-distribution. It is suitable for light-weight cryptographic devices such as sensor network motes and RFID tags....

  7. Site selective Cu2+ substitution in single crystal Fe3O4 biocompatible nanospheres by solvothermal reflux method

    Science.gov (United States)

    Manohar, A.; Krishnamoorthi, C.

    2017-09-01

    Transition metal cations distribution among tetrahedral and octahedral sites in Fe3O4 has profound influence on it properties. The cations distribution among these sites were influenced by crystal field stabilization energy (CFSE) of a substituent ion. It was reported that Cu2+ substitutes both Fe3+ in tetrahedral and Fe2+ in octahedral sites of magnetite though it has high CFSE for octahedral sites. Thus it promotes mixed (normal & inverse) spinel structure and hence the properties deviate from the prediction. Here we show that selective octahedral site substitution of Fe2+ by Cu2+ in single crystal Fe3O4 nanoparticles was possible by solvothermal reflux method at moderate temperatures (≈300 °C). It was attributed to reduced energy barrier for crystallization and high diffusion coefficient of the metal cations at moderate temperature in low viscous organic solvents mixture, at ambient pressure, compared to coprecipitation and solid state reaction protocols. In addition, effective removal of exothermic crystal lattice energy, released during nucleation and growth process, by natural gas bubbles formed in the reflux organic solvent mixture. This promotes effective diffusion of cations during the growth process and easy octahedral occupation by Cu2+ in Fe1-xCuxFe2O4 (x = 0, 0.1, 0.2, 0.3, 0.4, 0.5 & 0.6) single crystal nanospheres. The octahedral substitution was confirmed by reduction of crystal lattice parameter as well as ferromagnetic strength of octahedral sublattice with enhanced Cu2+ concentration. In addition, morphology, lattice vibrational frequency and electron excitation spectra of the nanospheres were studied. The Langevin function fit analysis reveals that superparamagnetic domain diameter were slightly less than the particle diameter obtained from TEM micrograph.

  8. In-situ solvothermal processing of polycaprolactone/hydroxyapatite nanocomposites with enhanced mechanical and biological performance for bone tissue engineering

    Directory of Open Access Journals (Sweden)

    Saeed Moeini

    2017-09-01

    Full Text Available The interest in biodegradable polymer-matrix nanocomposites with bone regeneration potential has been increasing in recent years. In the present work, a solvothermal process is introduced to prepare hydroxyapatite (HA nanorod-reinforced polycaprolactone in-situ. A non-aqueous polymer solution containing calcium and phosphorous precursors is prepared and processed in a closed autoclave at different temperatures in the range of 60–150 °C. Hydroxyapatite nanorods with varying aspect ratios are formed depending on the processing temperature. X-ray diffraction analysis and field-emission scanning electron microscopy indicate that the HA nanorods are semi-crystalline. Energy-dispersive X-ray spectroscopy and Fourier transform infrared spectrometry determine that the ratio of calcium to phosphorous increases as the processing temperature increases. To evaluate the effect of in-situ processing on the mechanical properties of the nanocomposites, highly porous scaffolds (>90% containing HA nanorods are prepared by employing freeze drying and salt leaching techniques. It is shown that the elastic modulus and strength of the nanocomposites prepared by the in-situ method is superior (∼15% to those of the ex-situ samples (blended HA nanorods with the polymer solution. The enhanced bone regeneration potential of the nanocomposites is shown via an in vitro bioactivity assay in a saturated simulated body fluid. An improved cell viability and proliferation is also shown by employing (3-(4,5- dimethylthiazol-2-yl-2, 5-diphenyl tetrazolium bromide (MTT assay in human osteosarcoma cell lines. The prepared scaffolds with in vitro regeneration capacity could be potentially useful for orthopaedic applications and maxillofacial surgery.

  9. An evaluation of entity and frequency based query completion methods

    NARCIS (Netherlands)

    Meij, E.; Mika, P.; Zaragoza, H.; Sanderson, M.; Zhai, C.; Zobel, J.; Allan, J.; Aslam, J.A.

    2009-01-01

    We present a semantic approach to suggesting query completions which leverages entity and type information. When compared to a frequency-based approach, we show that such information mostly helps rare queries.

  10. Tourette syndrome, growth retardation, and platyspondyly: an entity?

    NARCIS (Netherlands)

    Scheper, Frederike Y.; Hennekam, Raoul C. M.

    2002-01-01

    A 14-year-old male is described with Tourette syndrome, platyspondyly, a marked delay in bone age, growth retardation that is more expressed in the limbs and talipes equinovarus. This appears to be a new entity

  11. The entity-to-algorithm allocation problem: Extending the analysis

    CSIR Research Space (South Africa)

    Grobler, J

    2014-12-01

    Full Text Available This paper extends the investigation into the algorithm selection problem in hyper-heuristics, otherwise referred to as the entity-to-algorithm allocation problem, introduced by Grobler et al.. Two newly developed population-based portfolio...

  12. Fraud Indicators Applied to Legal Entities : An Empirical Ranking Approach

    NARCIS (Netherlands)

    S. van den Braak; R. Choenni; M.S. Bargh

    2014-01-01

    Legal persons (i.e., entities such as corporations, companies, partnerships, firms, associations, and foundations) may commit financial crimes or employ fraudulent activities like money laundering, tax fraud, or bankruptcy fraud. Therefore, in the Netherlands legal persons are automatically screened

  13. Knowledge environments representing molecular entities for the virtual physiological human.

    Science.gov (United States)

    Hofmann-Apitius, Martin; Fluck, Juliane; Furlong, Laura; Fornes, Oriol; Kolárik, Corinna; Hanser, Susanne; Boeker, Martin; Schulz, Stefan; Sanz, Ferran; Klinger, Roman; Mevissen, Theo; Gattermayer, Tobias; Oliva, Baldo; Friedrich, Christoph M

    2008-09-13

    In essence, the virtual physiological human (VPH) is a multiscale representation of human physiology spanning from the molecular level via cellular processes and multicellular organization of tissues to complex organ function. The different scales of the VPH deal with different entities, relationships and processes, and in consequence the models used to describe and simulate biological functions vary significantly. Here, we describe methods and strategies to generate knowledge environments representing molecular entities that can be used for modelling the molecular scale of the VPH. Our strategy to generate knowledge environments representing molecular entities is based on the combination of information extraction from scientific text and the integration of information from biomolecular databases. We introduce @neuLink, a first prototype of an automatically generated, disease-specific knowledge environment combining biomolecular, chemical, genetic and medical information. Finally, we provide a perspective for the future implementation and use of knowledge environments representing molecular entities for the VPH.

  14. Considering the health care entity C corporation conversion to tax pass-through entity status.

    Science.gov (United States)

    Reilly, Robert F

    2012-01-01

    The double taxation of C corporation income from operations and from the ultimate sale of its assets makes the C corporation an inefficient tax status for many health care entities. At the time of this writing, the changes in the federal tax law that are scheduled to take effect in 2013 will increase this level of double-taxation inefficiency. The owners of a C corporation practice can avoid the C corporation status tax inefficiency by converting the practice to either (1) S corporation status or (2) LLC status. The conversion of the health care C corporation to an S corporation may be accomplished without a current tax cost. However, the conversion of a health care C corporation to an LLC status can result in a current tax at both the corporation level and the shareholder level. Nonetheless, the current conversion tax cost may be less than the future tax cost (1) of operating the practice as a C corporation and incurring double taxation at what may be higher tax rates or (2) of incurring the higher tax cost (or reduced price) on the ultimate disposition of the practice assets and the attendant double taxation of the appreciation in the value of the practice assets. Since individual income tax rates on qualifying dividends from C corporations and on capital gains are currently at very low rates, this may be a good time for C corporation practice owners to consider the costs and benefits of a conversion to either S corporation status or LLC status. The practice owners should consult with their accounting, legal, and valuation advisors in order to consider all of the costs and benefits of a possible corporate tax status conversion. An estimation of both the costs and benefits of the corporate tax status conversion depends on the concluded fair market values of the medical practice, dental practice, or other health care entity assets. And, that practice asset appraisal should encompass all of the practice assets, both tangible assets and intangible assets.

  15. THE CORPORATE GOVERNANCE OF PUBLIC ENTITIES IN ROMANIA

    OpenAIRE

    Daniela Zapodeanu; Marcel Bolos; Lucia Kolozsi

    2009-01-01

    The paper aims to examine the application of principles of corporate governance fortransparency and efficiency of decision and control at the level of local public entities. We intend toargue the importance of these principles of governance in the public entities to determineresponsibility and management decision-making bodies in achieving the objectives in terms ofreliability of financial reporting, effectiveness and efficiency of operations, compliance withapplicable legislation.

  16. Memory-based named entity recognition in tweets

    OpenAIRE

    Bosch, A.P.J. van den; Bogers, T.

    2013-01-01

    We present a memory-based named entity recognition system that participated in the MSM-2013 Concept Extraction Challenge. The system expands the training set of annotated tweets with part-of-speech tags and seedlist information, and then generates a sequential memory-based tagger comprised of separate modules for known and unknown words. Two taggers are trained: one on the original capitalized data, and one on a lowercased version of the training data. The intersection of named entities in th...

  17. Entity-Based Discussion Forum for Drupal 7

    OpenAIRE

    Werling, Rasmus

    2011-01-01

    This thesis describes the planning and creation of an entity-based discussion forum module for the content management system Drupal 7. The main focus is on how the new entities in Drupal 7 are taken into use in a discussion forum module created from scratch. Also the database structure, the different implemented features and the integration with the Views module are explained. The major differences between Drupal 6 and Drupal 7 are dealt with as well: how everything circled around nod...

  18. Confidence Links Between Name Entities in Disparate Documents

    Science.gov (United States)

    2013-09-03

    200 is useful for various real-world applications, including information retrieval, question answering applica- tions, watch lists, and cross...natural language processing ( NLP ) applications. BACKGROUND Cross-document entity co-reference refers generally to the problem of identifYing whether...extracted while "city" and "Baghdad" refer to a second entity. Using the names using a different technique . Therefore, the various event from this

  19. Rediscovering perifollicular elastolysis: A hitherto undocumented entity in India

    Directory of Open Access Journals (Sweden)

    Shyam B Verma

    2015-01-01

    Full Text Available Perifollicular elastolysis, also known as papular acne scars is a common but taken for granted entity. It appears as asymptomatic whitish yellow papules on the trunk and proximal arms. Histologically there is loss of elastin around the pilosebaceous follicles. The lesions are the result of a scarring process that appear as papules and are often mistaken for papules of acne and are treated. A knowledge of this entity which has never been described before in India is being reiterated.

  20. EVOLUTION AND PERFORMANCE ANALYSIS FOR WINE ENTITIES IN ROMANIA

    OpenAIRE

    Dan Topor; Sorinel Capusneanu; Alina Putan

    2012-01-01

    The article aims to highlight the evolution of wine entities in Romania and theirperformance. Given the state of research conducted in the literature on performance measurementand analysis of the entities from wine sector and the achievements of specialists, the authors of thisarticle demonstrates the importance of using the method of variable costs in terms of its specificindicators and making any decisions based on information provided by them. The article ends withthe authors' conclusions ...

  1. 78 FR 18808 - Addition of Certain Persons to the Entity List; Removal of Person From the Entity List Based on...

    Science.gov (United States)

    2013-03-28

    ..., 2012). 0 2. Supplement No. 4 to part 744 is amended: 0 a. By removing under Canada, one Canadian entity.... Kevin J. Wolf, Assistant Secretary for Export Administration. BILLING CODE 3510-33-P ...

  2. 78 FR 3317 - Removal of Persons From the Entity List Based on Removal Request; Implementation of Entity List...

    Science.gov (United States)

    2013-01-16

    ..., and a 30-day delay in effective date are inapplicable because this regulation involves a military or... Russia, the Russian entity: ``Bolshaya Semenovskaya, 40/505, Moscow, Russia 107023; and Ulitsa...

  3. Graphene-supported SnO2 nanoparticles prepared by a solvothermal approach for an enhanced electrochemical performance in lithium-ion batteries

    OpenAIRE

    Wang, Bei; Su, Dawei; Park, Jinsoo; Ahn, Hyojun; Wang, Guoxiu

    2012-01-01

    SnO2 nanoparticles were dispersed on graphene nanosheets through a solvothermal approach using ethylene glycol as the solvent. The uniform distribution of SnO2 nanoparticles on graphene nanosheets has been confirmed by scanning electron microscopy and transmission electron microscopy. The particle size of SnO2 was determined to be around 5 nm. The as-synthesized SnO2/graphene nanocomposite exhibited an enhanced electrochemical performance in lithium-ion batteries, compared with bare graphene ...

  4. Synthesis of nanoscale titanium dioxide and its application in cancer therapy

    OpenAIRE

    Wang, Min; Zhou, Zhiguo; YANG Shiping

    2015-01-01

    As an important inorganic material,titanium dioxide gets more and more attention and is used in various fields,especially in the biomedical field.This paper summarizes the main synthesis methods of titanium dioxide nanomaterial and its applications in cancer therapy area.The titanium dioxide nanomaterial can be prepared by gas,liquid and solid phase methods.Among them,we mainly introduce liquid phase methods including sol-gel method,hydrothermal method,solvothermal,and microemulsion method.We...

  5. Synthesis of Core-Shell BiFeO3/ZnO nanostructures

    Science.gov (United States)

    White, Genevieve; Kang, Sungmu; Buechele, Andrew; Pegg, Ian; Philip, John

    2010-03-01

    We will discuss the synthesis of core-shell BiFeO3/ZnO nanoparticles, layer-by-layer using a combination solvothermal/hydrothermal synthetic method. The goal of this research was to synthesize novel magnetoelectric/semiconducting core-shell nanoparticles for building multifunctional devices. Furthermore, we will discuss (1) development of the combination synthetic method; (2) the effects of reactant concentration, pH, or time on the morphology of the particles; (3) the incorporation of dopants such as Mn into the ZnO shell; and (4) magnetic properties of the core-shell nanoparticles.

  6. Synthesis, Characterization, Luminescent and Nonlinear Optical Responses of Nanosized ZnO

    OpenAIRE

    Volodymyr V. Multian; Uklein, Andrii V.; Zaderko, Alexander N.; Kozhanov, Vadim O.; Boldyrieva, Olga Yu; Linnik, Rostyslav P.; Vladyslav V. Lisnyak; Gayvoronsky, Volodymyr Ya.

    2017-01-01

    In this study, we report soft and solvothermal methods for synthesis of zinc oxide nanoparticles (ZnO NPs). Both methods involve a precursor and are carried out at the middle low-temperature regime. The effect of different solvents on the ZnO NPs properties was studied. The nonlinear optical (NLO) response of the NPs was analyzed by the self-action of picosecond laser pulses at 1064?nm and by second harmonic generation (SHG) of a femtosecond laser pulses pump at 800?nm. The luminescence was s...

  7. 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.

  8. Evolutions and Trends in Presenting. The Balance Sheet as a Financial Position Picture of an Entity

    Directory of Open Access Journals (Sweden)

    Ecaterina Necsulescu

    2011-08-01

    Full Text Available In this article we proposed to achieve a synthesis of the key moments in the evolution of the concept of balance, of the theories formulated over time, of the presentation forms of the balance sheet, a taxonomy of balance sheets, supplemented by a breakdown of the concept of financial position and of the structures related to the assessment of the financial position. In other words, we will consider a gradual presentation of the concept of balance sheet over time and a presentation of the balance as the main tool for highlighting the patrimonial situation, of the assets of enterprise owners and of the picture on the financial position of an economic entity.

  9. Information rich mapping requirement to product architecture through functional system deployment: The multi entity domain approach

    DEFF Research Database (Denmark)

    Hauksdóttir, Dagny; Mortensen, Niels Henrik

    2017-01-01

    for mapping requirements to architecture. These approaches do not fully support the steps and information created during product design synthesis. Design Specifications used to guide the design are often documented in text based documents, outside the design models. This results in lack of traceability which......Successful transformation of design information from customer requirements to design implementation is critical for engineering design. As systems become complex the tracking of how customer requirements are implement becomes difficult. Existing approaches suggest so called domain modelling...... may impede the ability to evolve, maintain or reuse systems. In this paper the Multi Entity Domain Approach (MEDA) is presented. The approach combines different design information within the domain views, incorporates both Software and Hardware design and supports iterative requirements definition...

  10. DOES THE CONSTRUCT OF INTERNET ADDICTION REFLECT A SINGLE ENTITY OR A SPECTRUM OF DISORDERS?

    Directory of Open Access Journals (Sweden)

    Joël Billieux

    2017-02-01

    Full Text Available Objective: This article aimed to examine the issue of whether the construct of Internet addiction represents a single entity or a spectrum of disorders. Method: A literature review was performed and a conceptual synthesis was proposed. Results: Most research supports the notion that Internet addiction is a spectrum of Internet-related disorders, which pertain to addictive online behaviours, such as gaming and sexual activities. Although there are certain similarities between these behaviours, they are often associated with different socio-demographic and psychological variables (e.g., motivations and psychopathological symptoms, suggesting entities that are related, but still distinct. As constructs, addictive online activities are generally less heterogeneous than addictive use of the Internet, i.e., Internet addiction. Conclusions: The umbrella term “Internet addiction” is inadequate because it overlooks important differences between various addictive online activities. However, it may be unrealistic to expect a demise of the term before determining more clearly the acceptable level of internal heterogeneity of the psychopathological constructs.

  11. Named entity recognition for bacterial Type IV secretion systems.

    Directory of Open Access Journals (Sweden)

    Sophia Ananiadou

    2011-03-01

    Full Text Available Research on specialized biological systems is often hampered by a lack of consistent terminology, especially across species. In bacterial Type IV secretion systems genes within one set of orthologs may have over a dozen different names. Classifying research publications based on biological processes, cellular components, molecular functions, and microorganism species should improve the precision and recall of literature searches allowing researchers to keep up with the exponentially growing literature, through resources such as the Pathosystems Resource Integration Center (PATRIC, patricbrc.org. We developed named entity recognition (NER tools for four entities related to Type IV secretion systems: 1 bacteria names, 2 biological processes, 3 molecular functions, and 4 cellular components. These four entities are important to pathogenesis and virulence research but have received less attention than other entities, e.g., genes and proteins. Based on an annotated corpus, large domain terminological resources, and machine learning techniques, we developed recognizers for these entities. High accuracy rates (>80% are achieved for bacteria, biological processes, and molecular function. Contrastive experiments highlighted the effectiveness of alternate recognition strategies; results of term extraction on contrasting document sets demonstrated the utility of these classes for identifying T4SS-related documents.

  12. Annealing temperatures influence luminescence of YBO{sub 3}: Ce{sup 3+}, Yb{sup 3+} prepared by solvothermal method

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yue [Department of Physics, Northwest University, No. 229 Taibai North Road, Xi' an, Shaanxi, 710069 (China); Hu, Xiaoyun, E-mail: hxy3275@nwu.edu.cn [Department of Physics, Northwest University, No. 229 Taibai North Road, Xi' an, Shaanxi, 710069 (China); Zhan, Suchang; Sun, Xiao; Wang, Zhizhong; Miao, Tian; Miao, Hui [Department of Physics, Northwest University, No. 229 Taibai North Road, Xi' an, Shaanxi, 710069 (China); Fan, Jun [School of Chemical Engineering, Northwest University, No. 229 Taibai North Road, Xi' an, Shaanxi, 710069 (China)

    2014-08-01

    Near-infrared (NIR) quantum cutting (QC) YBO{sub 3}: Ce{sup 3+}, Yb{sup 3+} phosphors have been synthesized by solvothermal method with further heat treatment. The emission spectrum shows the Vis and NIR emission intensity of samples are both increasingly strong as annealing temperature rises when the annealing temperature is above 600 °C. Meanwhile the Vis emission of unannealed sample is observed. SEM images show that the sample annealed at different temperatures (200–900 °C) is mainly composed of nanosheets like potato chips, which is melt down granules after annealing treatment above 1000 °C.The crystal texture of all samples whether annealed or not is hexagonal through the analysis of XRD. The Raman and infrared spectrums indicate that the boron ions exist of BO{sub 4} units when the annealing temperature is above 600 °C. The infrared profile of unannealed sample shows that there are N–H units in the samples without annealing treatment. - Highlights: • The nanosheets like potato chips are synthesized by solvothermal method. • Annealing temperature is a great effect for luminescence of sample. • The boron ions exist of BO{sub 4} when the annealing temperature is above 600 °C, whose quantity determines the luminescent intensity. • According to the infrared profile of unannealed sample, there are N–H units, which are beneficial to the Vis emission.

  13. Solvothermal-induced 3D macroscopic SnO2/nitrogen-doped graphene aerogels for high capacity and long-life lithium storage.

    Science.gov (United States)

    Wang, Ronghua; Xu, Chaohe; Sun, Jing; Gao, Lian; Yao, Heliang

    2014-03-12

    3D macroscopic tin oxide/nitrogen-doped graphene frameworks (SnO2/GN) were constructed by a novel solvothermal-induced self-assembly process, using SnO2 colloid as precursor (crystal size of 3-7 nm). Solvothermal treatment played a key role as N,N-dimethylmethanamide (DMF) acted both as reducing reagent and nitrogen source, requiring no additional nitrogen-containing precursors or post-treatment. The SnO2/GN exhibited a 3D hierarchical porous architecture with a large surface area (336 m(2)g(-1)), which not only effectively prevented the agglomeration of SnO2 but also facilitated fast ion and electron transport through 3D pathways. As a result, the optimized electrode with GN content of 44.23% exhibited superior rate capability (1126, 855, and 614 mAh g(-1) at 1000, 3000, and 6000 mA g(-1), respectively) and extraordinary prolonged cycling stability at high current densities (905 mAh g(-1) after 1000 cycles at 2000 mA g(-1)). Electrochemical impedance spectroscopy (EIS) and morphological study demonstrated the enhanced electrochemical reactivity and good structural stability of the electrode.

  14. Solvothermal syntheses and characterization of three new silver(I)/copper(I)-thioarsenates based on As{sup 2+}/As{sup 3+} ions

    Energy Technology Data Exchange (ETDEWEB)

    Yao, Hua-Gang, E-mail: hgyao@gdpu.edu.cn [School of Chemistry and Chemical Engineering, Guangdong Pharmaceutical University, Zhongshan 528458 (China); Guangdong Cosmetics Engineering & Technology Research Center, Zhongshan 528458 (China); Tang, Cheng-Fei [School of Chemistry and Chemical Engineering, Guangdong Pharmaceutical University, Zhongshan 528458 (China); An, Yong-Lin [Department of Chemistry, Dalian University of Technology, Dalian 116024 (China); Ou, Zi-Jian; Wu, Guo-Hao; Lan, Pei; Zheng, Yi-Long [School of Chemistry and Chemical Engineering, Guangdong Pharmaceutical University, Zhongshan 528458 (China)

    2017-02-15

    Three new silver(I)/copper(I)-thioarsenates KAgAs{sup II}S{sub 2} (1), RbCu{sub 2}As{sup III}S{sub 3} (2) and RbCu{sub 4}As{sup III}S{sub 4} (3) have been solvothermally synthesized and structurally characterized. 1 exhibits a two-dimensional anionic network built up by As−As bond connecting the left- and right-handed helical [AgS{sub 2}]{sup 4−} chains, and represents the first examples of thioarsenates(II). The structure of 2 consists of two kinds of helical [Cu{sub 2}S{sub 3}]{sup 4–} chains linked by the arsenic atoms to form double layers with rubidium ions between the layers. Compound 3 is built up of infinite [Cu{sub 2}S{sub 2}]{sup 2–} chain and layered [Cu{sub 6}As{sub 2}S{sub 6}] linked to form a three-dimensional anionic framework, [Cu{sub 4}AsS{sub 4}]{sup –}, and containing channels in which the rubidium cations reside. The optical properties of 1–3 have been investigated by UV–vis spectroscopy. - Graphical abstract: Three new silver(I)/copper(I)-thioarsenates have been solvothermally synthesized and structurally characterized. 1 represents the first examples of thioarsenates(II) while compounds 2 and 3 possess noncondensed pyramidal AsS{sub 3}{sup 3–} unit.

  15. Enhanced Named Entity Extraction via Error-Driven Aggregation

    Energy Technology Data Exchange (ETDEWEB)

    Lemmond, T D; Perry, N C; Guensche, J W; Nitao, J J; Glaser, R E; Kidwell, P; Hanley, W G

    2010-02-22

    Despite recent advances in named entity extraction technologies, state-of-the-art extraction tools achieve insufficient accuracy rates for practical use in many operational settings. However, they are not generally prone to the same types of error, suggesting that substantial improvements may be achieved via appropriate combinations of existing tools, provided their behavior can be accurately characterized and quantified. In this paper, we present an inference methodology for the aggregation of named entity extraction technologies that is founded upon a black-box analysis of their respective error processes. This method has been shown to produce statistically significant improvements in extraction relative to standard performance metrics and to mitigate the weak performance of entity extractors operating under suboptimal conditions. Moreover, this approach provides a framework for quantifying uncertainty and has demonstrated the ability to reconstruct the truth when majority voting fails.

  16. A controlled vocabulary for pathway entities and events.

    Science.gov (United States)

    Jupe, Steve; Jassal, Bijay; Williams, Mark; Wu, Guanming

    2014-01-01

    Entities involved in pathways and the events they participate in require descriptive and unambiguous names that are often not available in the literature or elsewhere. Reactome is a manually curated open-source resource of human pathways. It is accessible via a website, available as downloads in standard reusable formats and via Representational State Transfer (REST)-ful and Simple Object Access Protocol (SOAP) application programming interfaces (APIs). We have devised a controlled vocabulary (CV) that creates concise, unambiguous and unique names for reactions (pathway events) and all the molecular entities they involve. The CV could be reapplied in any situation where names are used for pathway entities and events. Adoption of this CV would significantly improve naming consistency and readability, with consequent benefits for searching and data mining within and between databases. Database URL: http://www.reactome.org. © The Author(s) 2014. Published by Oxford University Press.

  17. Using Local Grammar for Entity Extraction from Clinical Reports

    Directory of Open Access Journals (Sweden)

    Aicha Ghoulam

    2015-06-01

    Full Text Available Information Extraction (IE is a natural language processing (NLP task whose aim is to analyze texts written in natural language to extract structured and useful information such as named entities and semantic relations linking these entities. Information extraction is an important task for many applications such as bio-medical literature mining, customer care, community websites, and personal information management. The increasing information available in patient clinical reports is difficult to access. As it is often in an unstructured text form, doctors need tools to enable them access to this information and the ability to search it. Hence, a system for extracting this information in a structured form can benefits healthcare professionals. The work presented in this paper uses a local grammar approach to extract medical named entities from French patient clinical reports. Experimental results show that the proposed approach achieved an F-Measure of 90. 06%.

  18. Cuban entities management. Cedrux just around the corner.

    Directory of Open Access Journals (Sweden)

    Tamara Rodríguez Sánchez

    2011-12-01

    Full Text Available The direction of the country as part of strengthening entities management and the informatization of Cuban society, presented the need to create a System of Enterprise Resource Planning (ERP, which would be able to computerize management processes of business and budgeted entities on national scale. It is in this way that since July 2008 CEDRUX product was developed composed by 15 subsystems. It will constitute the core on which new solutions will be developed that will extend its functionalities in a constantly way, including new entities management processes and allowing constant updating. In its first operational phase that will be in this very year 2011, Cedrux will only integrate 9 subsystems that will answer the economic needs of any organization.

  19. PERFORMANCE ANALYSIS OF AN ENTITY FROM CONSTRUCTION SECTOR USING DASHBOARD

    Directory of Open Access Journals (Sweden)

    SORIN BRICIU

    2015-12-01

    Full Text Available This research paper deals with the analysis of performances of economic entities from the construction sector from Romania. The necessary data for preparation and analysis up through dashboard of the economic entity are provided by managerial accounting through Target Costing method. The way of implementing and observing of stages which are completed in managerial accounting through Target Costing method are also presented in the paper based on the existing literature. For data analysis it was used a questionnaire based on three questions whose results were analyzed and which formed the basis of our entire course of scientific approach. The paper ends with the authors' conclusions about the performance analysis of economic entities in a construction project using dashboard showing the benefits of its long-term decisions.

  20. Event-Entity-Relationship Modeling in Data Warehouse Environments

    DEFF Research Database (Denmark)

    Bækgaard, Lars

    We use the event-entity-relationship model (EVER) to illustrate the use of entity-based modeling languages for conceptual schema design in data warehouse environments. EVER is a general-purpose information modeling language that supports the specification of both general schema structures and multi......-dimensional schemes that are customized to serve specific information needs. EVER is based on an event concept that is very well suited for multi-dimensional modeling because measurement data often represent events in multi-dimensional databases...

  1. Object-Relational Management of Multiply Represented Geographic Entities

    DEFF Research Database (Denmark)

    Friis-Christensen, Anders; Jensen, Christian Søndergaard

    2003-01-01

    Multiple representation occurs when information about the same geographic entity is represented electronically more than once. This occurs frequently in practice, and it invariably results in the occurrence of inconsistencies among the different representations. We propose to resolve this situation...... by introducing a multiple representation management system (MRMS), the schema of which includes rules that specify how to identify representations of the same entity, rules that specify consistency requirements, and rules used to restore consistency when necessary. In this paper, we demonstrate by means...

  2. Spatio-structural granularity of biological material entities

    Directory of Open Access Journals (Sweden)

    Vogt Lars

    2010-05-01

    Full Text Available Abstract Background With the continuously increasing demands on knowledge- and data-management that databases have to meet, ontologies and the theories of granularity they use become more and more important. Unfortunately, currently used theories and schemes of granularity unnecessarily limit the performance of ontologies due to two shortcomings: (i they do not allow the integration of multiple granularity perspectives into one granularity framework; (ii they are not applicable to cumulative-constitutively organized material entities, which cover most of the biomedical material entities. Results The above mentioned shortcomings are responsible for the major inconsistencies in currently used spatio-structural granularity schemes. By using the Basic Formal Ontology (BFO as a top-level ontology and Keet's general theory of granularity, a granularity framework is presented that is applicable to cumulative-constitutively organized material entities. It provides a scheme for granulating complex material entities into their constitutive and regional parts by integrating various compositional and spatial granularity perspectives. Within a scale dependent resolution perspective, it even allows distinguishing different types of representations of the same material entity. Within other scale dependent perspectives, which are based on specific types of measurements (e.g. weight, volume, etc., the possibility of organizing instances of material entities independent of their parthood relations and only according to increasing measures is provided as well. All granularity perspectives are connected to one another through overcrossing granularity levels, together forming an integrated whole that uses the compositional object perspective as an integrating backbone. This granularity framework allows to consistently assign structural granularity values to all different types of material entities. Conclusions The here presented framework provides a spatio

  3. Encoding of Fundamental Chemical Entities of Organic Reactivity Interest using chemical ontology and XML.

    Science.gov (United States)

    Durairaj, Vijayasarathi; Punnaivanam, Sankar

    2015-09-01

    Fundamental chemical entities are identified in the context of organic reactivity and classified as appropriate concept classes namely ElectronEntity, AtomEntity, AtomGroupEntity, FunctionalGroupEntity and MolecularEntity. The entity classes and their subclasses are organized into a chemical ontology named "ChemEnt" for the purpose of assertion, restriction and modification of properties through entity relations. Individual instances of entity classes are defined and encoded as a library of chemical entities in XML. The instances of entity classes are distinguished with a unique notation and identification values in order to map them with the ontology definitions. A model GUI named Entity Table is created to view graphical representations of all the entity instances. The detection of chemical entities in chemical structures is achieved through suitable algorithms. The possibility of asserting properties to the entities at different levels and the mechanism of property flow within the hierarchical entity levels is outlined. Copyright © 2015 Elsevier Inc. All rights reserved.

  4. FINANCIAL REPORTING IN PUBLIC INSTITUTIONS AND NON-FINANCIAL ENTITIES. SIMILARITIES AND DIFFERENCES

    OpenAIRE

    Daniela Vitan

    2011-01-01

    The present paperwork contains issues regarding financial reporting at the public institutions and non – financial entities. The main aspects are regarding the obligation of all entities to present the financial statements, the content of financial statements in public institutions and non-financial entities. Also, is presented the similarities and the differences aspects between financial reporting of these two patrimonial entities.

  5. Business Entity Selection: Why It Matters to Healthcare Practitioners. Part II--Corporations, Limited Liability Companies, and Professional Entities.

    Science.gov (United States)

    Nithman, Robert W

    2015-01-01

    The Bureau of Labor statistics indicates only a 50% four-year survivability rate among businesses classified as "education and health services." Gaining knowledge of IRS business entities can result in cost savings, operational efficiency, reduced liability, and enhanced sustainability. Each entity has unique disadvantages, depending on size, diversity of ownership, desire to expand, and profitability. Business structures should be compatible with organizational mission or vision statements, services and products, and professional codes of ethics. Healthcare reform will require greater business acumen. We have an ethical duty to disseminate and acquire the knowledge to properly establish and manage healthcare practices to ensure sustainable services that protect and serve the community.

  6. Evaluation of Named Entity Recognition in Dutch online criminal complaints

    NARCIS (Netherlands)

    Schraagen, M.P.; Brinkhuis, M.J.S.; Bex, F.J.

    2017-01-01

    The possibility for citizens to submit crime reports and criminal complaints online is becoming ever more common, especially for cyber- and internet-related crimes such as phishing and online trade fraud. Such user-submitted crime reports contain references to entities of interest, such as the

  7. Optimising closely held entities to enhance commercial participation ...

    African Journals Online (AJOL)

    The important contribution of the small business sector to economic growth and regional development is widely and generally acknowledged. In 1984, the South African Close Corporations Act introduced a simple, inexpensive and flexible closelyheld entity for the business consisting of a single entrepreneur or small ...

  8. 7 CFR 795.6 - Multiple individuals or other entities.

    Science.gov (United States)

    2010-01-01

    ... persons for the purpose of applying the limitation. In cases in which more than one rule would appear to be applicable, the rule which is most restrictive on the number of persons shall apply. ... Multiple individuals or other entities. The rules in §§ 795.5 through 795.16 shall be used to determine...

  9. 42 CFR 410.144 - Quality standards for deemed entities.

    Science.gov (United States)

    2010-10-01

    ... of continuing diabetes education concerning educational principles and behavior change strategies... dental care. (ix) Behavior change strategies, goal setting, risk factor reduction, and problem solving...-Management Training and Diabetes Outcome Measurements § 410.144 Quality standards for deemed entities. An...

  10. Principles and tools for collaborative entity-based intelligence analysis.

    Science.gov (United States)

    Bier, Eric A; Card, Stuart K; Bodnar, John W

    2010-01-01

    Software tools that make it easier for analysts to collaborate as a natural part of their work will lead to better analysis that is informed by more perspectives. We are interested to know if software tools can be designed that support collaboration even as they allow analysts to find documents and organize information (including evidence, schemas, and hypotheses). We have modified the Entity Workspace system, described previously, to test such designs. We have evaluated the resulting design in both a laboratory study and a study where it is situated with an analysis team. In both cases, effects on collaboration appear to be positive. Key aspects of the design include an evidence notebook optimized for organizing entities (rather than text characters), information structures that can be collapsed and expanded, visualization of evidence that emphasizes events and documents (rather than emphasizing the entity graph), and a notification system that finds entities of mutual interest to multiple analysts. Long-term tests suggest that this approach can support both top-down and bottom-up styles of analysis.

  11. Continuities and discontinuities between humans, intelligent machines, and other entities

    NARCIS (Netherlands)

    Soraker, Johnny

    2014-01-01

    When it comes to the question of what kind of moral claim an intelligent or autonomous machine might have, one way to answer this is by way of comparison with humans: Is there a fundamental difference between humans and other entities? If so, on what basis, and what are the implications for science

  12. Chemical named entities recognition: a review on approaches and applications.

    Science.gov (United States)

    Eltyeb, Safaa; Salim, Naomie

    2014-01-01

    The rapid increase in the flow rate of published digital information in all disciplines has resulted in a pressing need for techniques that can simplify the use of this information. The chemistry literature is very rich with information about chemical entities. Extracting molecules and their related properties and activities from the scientific literature to "text mine" these extracted data and determine contextual relationships helps research scientists, particularly those in drug development. One of the most important challenges in chemical text mining is the recognition of chemical entities mentioned in the texts. In this review, the authors briefly introduce the fundamental concepts of chemical literature mining, the textual contents of chemical documents, and the methods of naming chemicals in documents. We sketch out dictionary-based, rule-based and machine learning, as well as hybrid chemical named entity recognition approaches with their applied solutions. We end with an outlook on the pros and cons of these approaches and the types of chemical entities extracted.

  13. Lichen planus hypertrophicus of the vulva - a rare entity.

    Science.gov (United States)

    Job, Anupa Mary; Kaimal, Sowmya

    2017-09-01

    Vulvovaginal lichen planus is a type of chronic inflammatory dermatosis of the vulva, usually seen as a part of widespread lichen planus. The common clinical types of vulval lichen planus include papulosquamous, erosive and pigmented types. Hypertrophic lichen planus of the vulva is a rare entity. We report a case of hypertrophic lichen planus of the vulva which clinically simulated genital warts.

  14. 10 CFR 300.5 - Submission of an entity statement.

    Science.gov (United States)

    2010-01-01

    ... emission inventories, such as fossil fuel power plants, manufacturing facilities, commercial office... other than financial control; (4) The names of any parent or holding companies the activities of which... a complete emissions inventory under the 1605(b) program. (ii) The entity's emissions in its start...

  15. 31 CFR 306.88 - Political entities and public corporations.

    Science.gov (United States)

    2010-07-01

    ... (Continued) FISCAL SERVICE, DEPARTMENT OF THE TREASURY BUREAU OF THE PUBLIC DEBT GENERAL REGULATIONS GOVERNING U.S. SECURITIES Assignments in Behalf of Private or Public Organizations § 306.88 Political... 31 Money and Finance: Treasury 2 2010-07-01 2010-07-01 false Political entities and public...

  16. Primary Squamous Cell Carcinoma of Stomach: A Rare Entity ...

    African Journals Online (AJOL)

    How to cite this article: Patnayak R, Reddy V, Radhakrishnan, Jena A. Primary squamous cell carcinoma of stomach: A rare entity - case report and brief review of literature. J Surg Tech Case Report 2015;7:45-7. Source of Support: Nil, Conflict of Interest: None declared. Table 1: Primary SCC of stomach reported in literature.

  17. Primary Ovarian Leiomyoma: An Uncommon Entity ‑ Case Report ...

    African Journals Online (AJOL)

    Among all benign primary ovarian smooth muscle tumors, ovarian leiomyoma, is uncommon, accounting for 0.5-1% of all tumors. Most of these tumors are unilateral, small in size, and generally occur in premenopausal women. This paper presents a case report of primary ovarian leiomyoma, which is a rare entity, in a ...

  18. Detecting Underlying Stance Adopted When Human Construe Behavior of Entities

    Science.gov (United States)

    Terada, Kazunori; Ono, Kouhei; Ito, Akira

    Whether or not humans can construe the behaviors of entities depends on their psychological stance. The philosopher Dennett proposed human cognitive strategies (three stances) in which humans construe the behavior of other animated objects, including other humans, artifacts, and physical phenomena:‘intentional’, ‘design’ and ‘physical’ stances. Detecting the psychological stance taken toward entities is difficult, because such mental state attribution is a subjective cognitive process and hard to measure. In the present study, we proposed a novel method for detecting underlying stance adopted when human construe behavior of entities. In our method the subject was asked to select the most suitable action sequence shown in three movies each of which representing Dennett’s three stances. To valid our method we have conducted an experiment in which the subjects were presented thirty short videos and asked to compare them to the three movies. The result indicated that the subjects did not focused on prior knowledge about the entity but could focused on motion characteristics per se, owing to simple and typical motion of an abstract shaped object.

  19. Toxic cannabis psychosis is a valid entity | Solomons | South African ...

    African Journals Online (AJOL)

    One hundred black men admitted to hospital with acute psychiatric symptoms were investigated for the presence of urinary cannabis metabolltes in order to delineate the psychiatric role played by 'dagga', the potent South African cannabinol, in the study population and to determine the diagnostic value of the entity 'toxic ...

  20. Electricity: An Underlying Entity in Matter and Life, A Sustaining ...

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 17; Issue 4. Darshana Jolts - Electricity: an Underlying Entity in Matter and Life, A Sustaining Principle in Modern Civilization. V V Raman. Reflections Volume 17 Issue 4 April 2012 pp 393-405 ...

  1. Amelogenesis imperfecta and localised aggressive periodontitis: A rare clinical entity

    Directory of Open Access Journals (Sweden)

    Gayatri Gundannavar

    2013-01-01

    Full Text Available This case report presents two female patients whose chief complaint was discoloration of teeth. On careful clinical examination it was found that the patients had features of amelogenesis imperfecta and localised aggressive periodontitis. This article will give an insight of clinical and radiographic features of amelogenesis imperfecta with localised aggressive periodontitis, which is a rare clinical entity.

  2. 27 CFR 479.70 - Certain government entities.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 3 2010-04-01 2010-04-01 false Certain government entities. 479.70 Section 479.70 Alcohol, Tobacco Products, and Firearms BUREAU OF ALCOHOL, TOBACCO... obtain the approval of the Director as prescribed in § 479.62. Registration ...

  3. Urethral cavernous hemangioma in a female patient: a rare entity ...

    African Journals Online (AJOL)

    Genitourinary hemangiomas are rare entities of the urinary system. We reported a female patient who suffered dyspareunia and intermitant hematuria that was proved as urethral cavernous hemangioma. Despite its benign nature, hemangiomas may recur due to incomplet excision. Pan African Medical Journal 2015; 22 ...

  4. Secure Environments for Collaboration among Ubiquitous Roaming Entities

    DEFF Research Database (Denmark)

    Jensen, Christian D.

    2002-01-01

    SECURE is a newly started IST project, which addresses secure collaboration among computational entities in emerging global computing systems. The properties of these systems introduce new security challenges that are not adequately addressed by existing security models and mechanisms. The scale ...

  5. Entity Ranking on Graphs: Studies on Expert Finding

    NARCIS (Netherlands)

    Rode, H.; Serdyukov, Pavel; Hiemstra, Djoerd; Zaragoza, H.

    2007-01-01

    Todays web search engines try to offer services for finding various information in addition to simple web pages, like showing locations or answering simple fact queries. Understanding the association of named entities and documents is one of the key steps towards such semantic search tasks. This

  6. Example Based Entity Search in the Web of Data

    NARCIS (Netherlands)

    Bron, M.; Balog, K.; de Rijke, M.

    2013-01-01

    The scale of today's Web of Data motivates the use of keyword search-based approaches to entity-oriented search tasks in addition to traditional structure-based approaches, which require users to have knowledge of the underlying schema. We propose an alternative structure-based approach that makes

  7. Two-stage named-entity recognition using averaged perceptrons

    NARCIS (Netherlands)

    Buitinck, L.; Marx, M.

    2012-01-01

    We describe a simple approach to named-entity recognition (NER), aimed initially at the Dutch language, but potentially applicable to other languages. Our NER system employs a two-stage architecture, with handcrafted but dataset-independent features for both stages, and is on a par with

  8. Evaluation of Named Entity Recognition in Dutch Online Criminal Complaints

    NARCIS (Netherlands)

    Schraagen, M.P.|info:eu-repo/dai/nl/315552204; Brinkhuis, M.J.S.; Bex, F.J.|info:eu-repo/dai/nl/29609627X

    2017-01-01

    The possibility for citizens to submit crime reports and criminal complaints online is becoming ever more common, especially for cyber- and internet-related crimes such as phishing and online trade fraud. Such user-submitted crime reports contain references to entities of interest, such as the

  9. Visual analysis of entity relationships in the Global Terrorism Database

    Science.gov (United States)

    Godwin, Alex; Chang, Remco; Kosara, Robert; Ribarsky, William

    2008-04-01

    With the increase of terrorist activity around the world, it has become more important than ever to analyze and understand these activities over time. Although the data on terrorist activities are detailed and relevant, the complexity of the data has rendered the understanding and analysis difficult. We present a visual analytical approach to effectively identify related entities such as terrorist groups, events, locations, etc. based on a 2D layout. Our methods are based on sequence comparison from bioinformatics, modified to incorporate the element of time. By allowing the user the freedom to link entities by their activities over time, we provide a new framework for comparison of event sequences. Our scoring mechanism is robust and flexible, giving the user the flexibility to define the extent to which time is considered in aligning entities. Incorporated with high interactivity, the user can efficiently navigate through tens of thousands of records recorded in over a hundred dimensions of data by choosing combinations of categories to examine. Exploration of the terrorist activities in our system reveals relationships between entities that are not easily detectable using traditional methods.

  10. 76 FR 78146 - Addition of Certain Persons to the Entity List; and Implementation of Entity List Annual Review...

    Science.gov (United States)

    2011-12-16

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF COMMERCE..., Commerce. ACTION: Final rule. SUMMARY: This rule amends the Export Administration Regulations (EAR) by... concerning one person located in Malaysia to add an alternate address. The Entity List provides notice to the...

  11. Effect of electrolytes nature and concentration on the morphology and structure of MoS{sub 2} nanomaterials prepared using one-pot solvothermal method

    Energy Technology Data Exchange (ETDEWEB)

    Akram, H., E-mail: akramhanane@yahoo.fr [Instituto de Catálisis y Petroleoquímica, CSIC, C/Marie Curie 2, Cantoblanco, 28049 Madrid (Spain); Laboratoire de Génie Chimique et Valorisation des Ressources, Faculté des Sciences et Techniques de Tanger, Université Abdelmalek Essâadi, B.P. 416 Tangier (Morocco); Mateos-Pedrero, C., E-mail: cmpedrero@yahoo.es [Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculdade de Engenharia da Universidade do Porto Rua Roberto Frias, s/n4200-465, Porto (Portugal); Gallegos-Suárez, E.; Guerrero-Ruíz, A. [Instituto de Catálisis y Petroleoquímica, CSIC, C/Marie Curie 2, Cantoblanco, 28049 Madrid (Spain); Grupo de Diseño y Aplicación de Catalizadores Heterogéneos, Unidad Asociada UNED—ICP (CSIC), Madrid (Spain); Chafik, T. [Laboratoire de Génie Chimique et Valorisation des Ressources, Faculté des Sciences et Techniques de Tanger, Université Abdelmalek Essâadi, B.P. 416 Tangier (Morocco); Rodríguez-Ramos, I. [Instituto de Catálisis y Petroleoquímica, CSIC, C/Marie Curie 2, Cantoblanco, 28049 Madrid (Spain); Grupo de Diseño y Aplicación de Catalizadores Heterogéneos, Unidad Asociada UNED—ICP (CSIC), Madrid (Spain)

    2014-07-01

    Different MoS{sub 2} nanostructures have been obtained following an innovative one-step solvothermal method by changing the concentration and type of the electrolyte while avoiding the use of surfactant. It was found that the chemical nature of the studied electrolyte ((NH{sub 4}){sub 2}CO{sub 3} or KCl) do not significantly affect the morphology and structure of the obtained MoS{sub 2} nanomaterials. Nevertheless, increasing the electrolyte concentration yields to a remarkable modification of the morphology of the resulting MoS{sub 2} from nanospheres to worm-shaped then finally to nanotubes. All the obtained nanomaterials were characterized by X-ray diffraction, (XRD), transmission electron microscopy (TEM, HRTEM), Fourier transformation infra-red spectroscopy (FTIR), thermogravimetric analysis (TGA) and X-ray photoelectron spectroscopy (XPS).

  12. Effects of the volume ratio of water and ethanol on morphosynthesis and photocatalytic activity of CaTiO3 by a solvothermal process

    Science.gov (United States)

    Dong, Weixia; Song, Bin; Zhao, Gaoling; Meng, Weijie; Han, Gaorong

    2017-05-01

    Solvothermal production of large surface area, dendritic CaTiO3 crystals exhibiting enhanced photocatalytic activity is facilitated through careful control of the volume ratio of water and ethanol in high pH (≥12) samples. The study was performed without the use of templates or surfactants. Results show the volume ratio of water and ethanol had significant effect on sample morphosynthesis. Depending on solvent ratios, results ranged from imperfect dendrites, to four-arm petal-like dendrites, four-arm dendrites mixed with butterfly-like dendrites, and regular and aggregated prisms. Results show the four-arm dendritic sample exhibiting superior photocatalytic activity arising from a unique morphology and large surface area capable of enhanced light harvesting.

  13. Graphene-supported SnO2 nanoparticles prepared by a solvothermal approach for an enhanced electrochemical performance in lithium-ion batteries.

    Science.gov (United States)

    Wang, Bei; Su, Dawei; Park, Jinsoo; Ahn, Hyojun; Wang, Guoxiu

    2012-04-13

    SnO2 nanoparticles were dispersed on graphene nanosheets through a solvothermal approach using ethylene glycol as the solvent. The uniform distribution of SnO2 nanoparticles on graphene nanosheets has been confirmed by scanning electron microscopy and transmission electron microscopy. The particle size of SnO2 was determined to be around 5 nm. The as-synthesized SnO2/graphene nanocomposite exhibited an enhanced electrochemical performance in lithium-ion batteries, compared with bare graphene nanosheets and bare SnO2 nanoparticles. The SnO2/graphene nanocomposite electrode delivered a reversible lithium storage capacity of 830 mAh g-1 and a stable cyclability up to 100 cycles. The excellent electrochemical properties of this graphene-supported nanocomposite could be attributed to the insertion of nanoparticles between graphene nanolayers and the optimized nanoparticles distribution on graphene nanosheets.

  14. Microwave-assisted solvothermal synthesis of novel hierarchical BiOI/rGO composites for efficient photocatalytic degardation of organic pollutants

    Science.gov (United States)

    Niu, Jinfen; Dai, Peixuan; Zhang, Qian; Yao, Binghua; Yu, Xiaojiao

    2018-02-01

    In the present paper, a novel composite of BiOI/rGO with excellent visible-light photocatalytic activity was successfully fabricated via very different simple, fast and mild rapid microwave hydrothermal method. The BiOI/rGO -1(BG-1) was donated as a simple chemical mechanical and the BiOI/rGO -2(BG-2) was donated as one-step rapid microwave hydrothermal method. The BG-1 were composed of the BiOI microspheres with a diameter of about 1 μm and mixed heterogeneously with graphene. While, the BG-2 were consist of the BiOI nanoplates with the thickness of approximately 20 nm dispersed heterogeneously on the surface of rGO. The degradation of 40 mg/L methylene blue (MB) and 20 mg/L levofloxacin (LEV) under visible light irradiation can reach about 11 and 3 times than that of P25, respectively. Furthermore, the reactive species of hole was determined to dominant the photodegradation process. The intensive photocatlytic could ascribe to more effective electron transportation and separations, this conclusion was different with other studies. A possible photocatalytic mechanism of BG-2 was also proposed.

  15. Effect of organic solvents on particle size of Mn{sub 3}O{sub 4} nanoparticles synthesized by a solvothermal method

    Energy Technology Data Exchange (ETDEWEB)

    Song, Rui [Research Institute, Jilin Petrochemical Company Ltd., Jilin 132021 (China); Feng, Shouhua, E-mail: shfeng@mail.jlu.edu.cn [State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, College of Chemistry, Jilin University, Changchun 130012 (China); Wang, Hongjun [Sales and Management Department, Jilin Petrochemical Company Ltd., Jilin 132002 (China); Hou, Changmin [State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, College of Chemistry, Jilin University, Changchun 130012 (China)

    2013-06-15

    In this paper, a modified simple solvothermal method is employed to synthesize Mn{sub 3}O{sub 4} nanocrystals using four different solvents: acetone, ethanol, N,N-dimethylformamide (DMF), and dimethyl sulfoxide (DMSO). Mn{sub 3}O{sub 4} nanoparticles with a tetragonal hausmannite nano-structure are characterized by powder X-ray diffraction (XRD), transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM), Fourier transform infrared spectroscopy (FTIR), as well as superconducting quantum interference device magnetometer (SQUID). The Mn{sub 3}O{sub 4} particle size is found to have a strong dependency on the solvent used. A reaction scheme is proposed to understand this dependency, suggesting that the solvent coordinating capability has a critical effect on Mn{sub 3}O{sub 4} particle size. The stronger the coordinating capability of the solvent is, the smaller the Mn{sub 3}O{sub 4} particle size is. In addition, magnetic properties of the nano-structured Mn{sub 3}O{sub 4} are also tested and discussed. - Graphical abstract: The comparison of the particle size of Mn{sub 3}O{sub 4} nanoparticles synthesized using different solvents and HRTEM image of Mn{sub 3}O{sub 4} individual nanoparticle revealed its single-crystal nature. - Highlights: • Mn{sub 3}O{sub 4} nanocrystals were synthesized using different solvents by a solvothermal method. • The particle size of Mn{sub 3}O{sub 4} nanocrystal is found to have a strong dependency on the solvent used. • A reaction mechanism is proposed to explain the difference of particle size of Mn{sub 3}O{sub 4} nanocrystals. • Magnetic properties of Mn{sub 3}O{sub 4} nanocrystals with different particle size are tested and compared.

  16. One-pot solvothermal preparation and enhanced photocatalytic activity of metallic silver and graphene co-doped BiVO{sub 4} ternary systems

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Lei; Wei, Yongge [School of Chemistry and Environmental Engineering, Changchun University of Science and Technology, Changchun 130022 (China); Guo, Wan [School of Chemistry, Northeast Normal University, Changchun 130024 (China); Guo, Yihang, E-mail: guoyh@nenu.edu.cn [School of Environment, Northeast Normal University, Changchun 130117 (China); Guo, Yingna [School of Chemistry, Northeast Normal University, Changchun 130024 (China)

    2015-03-30

    Graphical abstract: - Highlights: • We have obtained Ag/GR/BiVO{sub 4} ternary system by one-pot solvothermal route. • The best photocatalytic activity to RhB has been attained for 3%Ag/5%GR/BiVO{sub 4}. • Silver nanoparticles and graphene nanosheets doping clearly favor the photocarriers separation. • The Ag/GR/BiVO{sub 4} heterojunction photocatalyst can be reused five times without obvious loss of the reactivity. - Abstract: A series of metallic silver and graphene (GR) co-doped monoclinic BiVO{sub 4} ternary systems (Ag/GR/BiVO{sub 4}) are demonstrated by a single-step solvothermal method. The phase and chemical structure, morphology, textural and optical absorption properties of the Ag/GR/BiVO{sub 4} ternary systems are well characterized, and then their simulated sunlight and visible-light photocatalytic activity were evaluated by the degradation of a typical dye pollutant, rhodamine B (RhB). For comparison, binary systems of Ag/BiVO{sub 4} and GR/BiVO{sub 4} as well as solitary BiVO{sub 4} are also tested under the same conditions. Meanwhile, the separation and transportation of the photogenerated carriers in the simulated sunlight-irradiating Ag/GR/BiVO{sub 4} ternary systems are studied by photoelectrochemistry experiments, and the active species generated during the process of photodegradation are investigated by free radical and hole scavenging experiments. On the basis of the above results, mechanism of photocatalytic degradation of RhB over the Ag/GR/BiVO{sub 4} ternary system is revealed. Finally, the reusability of the catalyst was evaluated by five consecutive catalytic runs.

  17. Solvothermal fabrication and enhanced visible light photocatalytic activity of Cu{sub 2}O-reduced graphene oxide composite microspheres for photodegradation of Rhodamine B

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Lingling [Hubei Collaborative Innovation Center for Rare Metal Chemistry, Hubei Normal University, Huangshi 435002 (China); Hubei Key Laboratory of Pollutant Analysis and Reuse Technology, Hubei Normal University, Huangshi 435002 (China); Wang, Guohong, E-mail: wanggh2003@163.com [Hubei Collaborative Innovation Center for Rare Metal Chemistry, Hubei Normal University, Huangshi 435002 (China); Hubei Key Laboratory of Pollutant Analysis and Reuse Technology, Hubei Normal University, Huangshi 435002 (China); Hao, Ruirui [Hubei Collaborative Innovation Center for Rare Metal Chemistry, Hubei Normal University, Huangshi 435002 (China); Hubei Key Laboratory of Pollutant Analysis and Reuse Technology, Hubei Normal University, Huangshi 435002 (China); Han, Deyan, E-mail: handeyan@sohu.com [Hubei Collaborative Innovation Center for Rare Metal Chemistry, Hubei Normal University, Huangshi 435002 (China); Hubei Key Laboratory of Pollutant Analysis and Reuse Technology, Hubei Normal University, Huangshi 435002 (China); Cao, Sheng [Hubei Collaborative Innovation Center for Rare Metal Chemistry, Hubei Normal University, Huangshi 435002 (China); Hubei Key Laboratory of Pollutant Analysis and Reuse Technology, Hubei Normal University, Huangshi 435002 (China)

    2015-12-15

    Graphical abstract: - Highlights: • Cu{sub 2}O-reduced graphene oxide composite spheres were successfully prepared. • The graphene oxide loading played an important role in photocatalytic activity. • A possible enhanced photocatalytic mechanism was proposed. - Abstract: The addition of graphene oxide (GO) in the semiconductors has been regarded as one of the effective methods to enhance their photocatalytic activity. In this study, Cu{sub 2}O-reduced graphene oxide (Cu{sub 2}O-rGO) composites with low loading (0–0.5 wt.%) of graphene oxide (GO) were produced by a one-step green solvothermal method in ethanol system by using Cu(NO{sub 3}){sub 2}·3H{sub 2}O and glutamic acid as copper precursor and reducing agent, respectively. During the solvothermal treatment, GO was reduced to rGO. The as-prepared Cu{sub 2}O-reduced graphene oxide composite microspheres exhibited enhanced photocatalytic activity toward the degradation of RhB aqueous solution under visible light irradiation. At the optimal loading of graphene oxide (0.05 wt.%), Cu{sub 2}O-rGO composites showed the highest photocatalytic activity, exceeding that of pure Cu{sub 2}O and commercial Degussa P25 by a factor of 2.9 and 7.9, respectively. The enhanced photocatalytic activity may be ascribed to the strong coupling interaction between Cu{sub 2}O particles and rGO nanosheets, which reduces the recombination of charge carriers.

  18. Controlling the morphology and properties of solvothermal synthesized Cu{sub 2}ZnSnS{sub 4} nanoparticles by solvent type

    Energy Technology Data Exchange (ETDEWEB)

    Bahramzadeh, Saeid [School of Metallurgy and Materials Engineering, College of Engineering, University of Tehran, Tehran (Iran, Islamic Republic of); Abdizadeh, Hossein [School of Metallurgy and Materials Engineering, College of Engineering, University of Tehran, Tehran (Iran, Islamic Republic of); Center of Excellence for High Performance Materials, University of Tehran, Tehran (Iran, Islamic Republic of); Golobostanfard, Mohammad Reza, E-mail: Bostanfr@ut.ac.ir [School of Metallurgy and Materials Engineering, College of Engineering, University of Tehran, Tehran (Iran, Islamic Republic of)

    2015-09-05

    Highlights: • CZTS nanoparticles are fabricated by solvothermal method with different solvents. • Different morphologies are achieved by EDA, TETA, EG, and OA solvents. • Property and chelating ability of the solvents have a key role on nanoparticles formation. • TETA and OA are strongly recommended for solar cell applications. - Abstract: The copper–zinc–tin sulfide Cu{sub 2}ZnSnS{sub 4} (CZTS) semiconductors are recently considered as one of the favorable materials for application as absorber layers in solar cells due to their appropriate direct band gap energy and high optical absorption coefficient. In this study, the effect of solvent type on properties of solvothermal synthesized CZTS nanoparticles has been investigated. Ethylenediamine (EDA), triethylenetetramine (TETA), ethylene glycol (EG), and oleic acid (OA) have been used as the solvent. X-ray diffraction technique and Raman spectroscopy confirmed the formation of crystalline CZTS nanoparticles with kesterite crystal structure in these solvents with the exception of EDA, which forms wurtzite crystal structure. Morphological characterizations show that several distinct morphologies including spherical (70–160 nm), nanoplates (∼45 nm thickness and more than 1 μm length), peculiar flower-like particles (with diameter of ∼0.4–1.5 μm), truncated hexagonal disks, irregular particles, and hexagonal microdisks are obtained by varying the solvent type. Optical studies revealed broad absorption of the CZTS particles in the visible region. Compared with other solvents, OA synthesized CZTS particles show higher absorption in the visible region. However, CZTS nanoparticles synthesized by TETA solvent show the most appropriate properties for application as an absorber materials in solar cells due to high crystallinity, low impurity phases, suitable size, and proper band gap energy.

  19. Synthesis of belt-like BiOBr hierarchical nanostructure with high photocatalytic performance

    Energy Technology Data Exchange (ETDEWEB)

    Li, Haiping [National Engineering Technology Research Center for Colloidal Materials, Shandong University, Jinan 250100 (China); Liu, Jingyi; Hu, Tingxia [Environment Research Institute, Shandong University, Jinan 250100 (China); Du, Na; Song, Shue [Key Laboratory of Colloid and Interface Chemistry (Ministry of Education), Shandong University, Jinan 250100 (China); Hou, Wanguo, E-mail: wghou@sdu.edu.cn [Key Laboratory of Colloid and Interface Chemistry (Ministry of Education), Shandong University, Jinan 250100 (China)

    2016-05-15

    Highlights: • BiOBr hierarchical nanobelts (NBs) were solvothermally prepared. • NBs show higher specific surface area and photoabsorption than BiOBr nanosheets. • NBs exhibit higher photoactivity than the nanosheets. - Abstract: One-dimensional (1D) bismuth oxyhalide (BiOX) hierarchical nanostructures are always difficult to prepare. Herein, we report, for the first time, a simple synthesis of BiOBr nanobelts (NBs) via a facile solvothermal route, using bismuth subsalicylate as the template and bismuth source. The BiOBr nanobelts are composed of irregular single crystal nanoparticles with highly exposed (0 1 0) facets. Compared with the BiOBr nanosheets (NSs) with dominant exposed (0 0 1) facets, they exhibit higher photocatalytic activity toward degradation of Rhodamine B and Methylene Blue under visible light irradiation. The higher photocatalytic performance of BiOBr NBs arises from their larger specific surface area and higher photoabsorption capability. This study provides a simple route for synthesis of belt-like Bi-based hierarchical nanostructures.

  20. Central dot sign in entities other than Caroli disease

    Energy Technology Data Exchange (ETDEWEB)

    Ahmadi, T.; Itai, Yuji [Tsukuba Univ., Ibaraki (Japan). Inst. of Clinical Medicine; Minami, Manabu

    1997-11-01

    The purpose of this study was to describe central dot sign (tiny dots with strong contrast enhancement of the portal vein within dilated hepatic bile ducts on computed tomography) in entities other than Caroli disease, especially in peribiliary cysts with or without autosomal-dominant polycystic kidney disease. Computed tomography in 74 cases of peribiliary cysts and 134 cases of other liver diseases and states possibly showing central dot sign were retrospectively reviewed to examine the central dot sign. In three cases of peribiliary cysts, some part of the liver showed strongly enhanced portal radicles surrounded completely or partially by low-attenuation, enlarged peribiliary cysts, presenting ``central dot sign`` on contrast-enhanced computed tomography. We suggest that in addition to Caroli disease, some other entities and diseases of the liver may demonstrate central dot sign and this sign should not be considered a specific finding of Caroli disease. (author)

  1. Linear interstitial keratitis: a distinct clinical entity revisited.

    Science.gov (United States)

    Calvo, Charles M; Sikder, Shameema; Mamalis, Nick; Mifflin, Mark D

    2012-12-01

    Few reports in the ophthalmic literature describe rare corneal lesions of the stroma that present in a horizontal linear fashion. Although some differences exist among the small number of reported cases, we believe that all these cases represent a distinct clinical entity appropriately titled linear interstitial keratitis. In an attempt to expand the knowledge of this condition of unknown etiology, we present 3 cases of linear interstitial keratitis. Case series (3 cases are presented) and literature review. All 3 patients (aged 21-22 years) presented with horizontal linear stromal infiltrates. One patient presented with a corneal perforation, requiring a closure with 3 interrupted sutures. Another patient required a penetrating keratoplasty because of a visually significant central scar. All 3 patients responded to topical steroids. Linear interstitial keratitis is a rare clinical entity and its histopathologic etiology remains undetermined. Current available technology including specular microscopy, anterior segment optical coherence tomography, and more sensitive serological testing may permit a better understanding of this disease.

  2. Congenital hernia of cord: an often misdiagnosed entity

    Science.gov (United States)

    Raju, Rubin; Satti, Mohamed; Lee, Quoc; Vettraino, Ivana

    2015-01-01

    Congenital hernia of the cord, also known as umbilical cord hernia, is an often misdiagnosed and under-reported entity, easily confused with a small omphalocele. It is different from postnatally diagnosed umbilical hernias and is believed to arise from persistent physiological mid-gut herniation. Its incidence is estimated to be 1 in 5000. Unlike an omphalocele, it is considered benign and is not linked with chromosomal anomalies. It has been loosely associated with intestinal anomalies, suggesting the need for a complete fetal anatomical ultrasound evaluation. We present a case of a fetal umbilical cord hernia diagnosed in a 28-year-old woman at 21 weeks gestation. The antenatal and intrapartum courses were uncomplicated. It was misdiagnosed postnatally as a small omphalocele, causing unwarranted anxiety in the parents. Increased awareness and knowledge of such an entity among health professionals is important to prevent unwarranted anxiety from misdiagnosis, and inadvertent bowel injury during cord clamping at delivery. PMID:25899514

  3. Adaptive, Multilingual Named Entity Recognition in Web Pages

    OpenAIRE

    Petasis, Georgios; Karkaletsis, Vangelis; Grover, Claire; Hachey, Ben; Pazienza, Maria Teresa; Vindigni, Michele; Coch, José

    2004-01-01

    Most of the information on the Web today is in the form of HTML documents, which are designed for presentation purposes and not for machine understanding and reasoning. Existing web extraction systems require a lot of human involvement for maintenance due to changes to targeted web sites and for adaptation to new web sites or even to new domains. This paper presents the adaptive, multilingual named entity recognition and classification (NERC) technologies developed for processing web pages in...

  4. Representing electrons a biographical approach to theoretical entities

    CERN Document Server

    Arabatzis, Theodore

    2006-01-01

    Both a history and a metahistory, Representing Electrons focuses on the development of various theoretical representations of electrons from the late 1890s to 1925 and the methodological problems associated with writing about unobservable scientific entities. Using the electron-or rather its representation-as a historical actor, Theodore Arabatzis illustrates the emergence and gradual consolidation of its representation in physics, its career throughout old quantum theory, and its appropriation and reinterpretation by chemists. As Arabatzis develops this novel biographical

  5. Magnetic studies of iron-entities in human tissues

    Energy Technology Data Exchange (ETDEWEB)

    Slawska-Waniewska, A. E-mail: slaws@ifpan.edu.pl; Mosiniewicz-Szablewska, E.; Nedelko, N.; Galazka-Friedman, J.; Friedman, A

    2004-05-01

    Iron-entities in the human liver, brain and blood tissues have been investigated by means of EPR spectroscopy and magnetization measurements over the temperature range 4-300 K. The identification of the most typical forms of iron in the human body (i.e. isolated Fe-ions bonded in hemoglobin and transferrin as well as exchange coupled Fe-ions in nanosized ferritin cores) is presented.

  6. SALES BUDGET - MANAGEMENT TOOL IN BUSINESS BACKGROUND ENTITY

    OpenAIRE

    Cristina-Otilia, TENOVICI

    2014-01-01

    Budget as a management tool is used to size the activity of forecasting the financial and accounting terms and in terms of economic efficiency, the allocation and use of resources to an entity in a particular reporting period, that aims to achieve the necessary expenses and income achieved, establishing this and the powers and responsibilities relating to the efficient use of these resources. Sales budgeting should be given special attention given the correlation and the influence of these pr...

  7. The Use of Management Accounting Tools in Third Sector Entities

    Directory of Open Access Journals (Sweden)

    Poueri do Carmo Mário

    2013-04-01

    Full Text Available The purpose of this article was to present the results of research about the use of management accounting tools by third sector entities. It was considered that the use of management tools assists in the management process and internal controls of the same, and consequently in its continuity. The literature discusses the importance of management accounting and its instruments for management purposes (Padoveze, 2004; Soutes, 2006; Pace, 2009 and presents relevant aspects of more traditional tools such as the Budget, Strategic Planning and Costing (Dubois, Kulpa and Souza, 2006; Martins, 2010; Padoveze, 2006. We tried to do a survey on a sample of NGOs in cities of Minas Gerais, which included at the end with 41 respondents institutions. The survey instrument for data collection was a questionnaire constructed from literature reviews related to objects of research (Third Sector and Management Accounting Instruments. The questionnaire had the purpose of gathering data from the entity and also know about of the respondent. In addition, interviews were conducted in some NGOs, complementing the research findings from the questionnaires. The results were divided into three topics: the respondent data, the organization and practices of management accounting. In general, although much progress has been made and success stories and effective improvements, most of these entities still need to develop their accounting information systems and the use of the instruments themselves. Causes of this may be the lack of knowledge about some of the entities management tools (maybe the respondents because of their formations, besides the reduced capacity of most of them have these "services" (controls and analyzes that run on its functional structure due lack of resources to do so.

  8. Leiomyosarcoma of Penis: An Aggressive and Exceptionally Rare Entity.

    Science.gov (United States)

    Trivedi, Vinita; A, Muneer; Rani, Rita; Chauhan, Richa; Singh, Usha; Kuna, Naveen

    2017-09-01

    Penile leiomyosarcoma is a very rare disease of penile mesenchymal tissue, most of them are of vascular origin and pathologically classified into the superficial and deep type. Because of the small number of cases reported so far, the conclusions about treatment and prognosis are equivocal. Here we report a case of 40-year old patient who presented with leiomyosracoma of penis; despite adequate surgery patient developed local recurrence and distant metastasis indicating aggressive nature of leiomyosarcoma entity of penis.

  9. Modeling discrete and continuous entities with fractions and decimals.

    Science.gov (United States)

    Rapp, Monica; Bassok, Miriam; DeWolf, Melissa; Holyoak, Keith J

    2015-03-01

    When people use mathematics to model real-life situations, their use of mathematical expressions is often mediated by semantic alignment (Bassok, Chase, & Martin, 1998): The entities in a problem situation evoke semantic relations (e.g., tulips and vases evoke the functionally asymmetric "contain" relation), which people align with analogous mathematical relations (e.g., the noncommutative division operation, tulips/vases). Here we investigate the possibility that semantic alignment is also involved in the comprehension and use of rational numbers (fractions and decimals). A textbook analysis and results from two experiments revealed that both mathematic educators and college students tend to align the discreteness versus continuity of the entities in word problems (e.g., marbles vs. distance) with distinct symbolic representations of rational numbers--fractions versus decimals, respectively. In addition, fractions and decimals tend to be used with nonmetric units and metric units, respectively. We discuss the importance of the ontological distinction between continuous and discrete entities to mathematical cognition, the role of symbolic notations, and possible implications of our findings for the teaching of rational numbers. PsycINFO Database Record (c) 2015 APA, all rights reserved.

  10. 76 FR 66074 - Small Entity Compliance Guide: Required Warnings for Cigarette Packages and Advertisements...

    Science.gov (United States)

    2011-10-25

    ... Cigarette Packages and Advertisements; Availability AGENCY: Food and Drug Administration, HHS. ACTION... industry entitled ``Required Warnings for Cigarette Packages and Advertisements--Small Entity Compliance... entitled ``Required Warnings for Cigarette Packages and Advertisements--Small Entity Compliance Guide'' to...

  11. 77 FR 70163 - Recognition of Entities for the Accreditation of Qualified Health Plans

    Science.gov (United States)

    2012-11-23

    ... the National Committee for Quality Assurance (NCQA) and URAC as recognized accrediting entities for the purposes of fulfilling the accreditation requirement as part of qualified health plan... HUMAN SERVICES Recognition of Entities for the Accreditation of Qualified Health Plans AGENCY...

  12. Synthesis and structure of undoped and indium-doped thermoelectric lead telluride nanoparticles

    Science.gov (United States)

    Kadel, Kamal; Kumari, Latha; Wang, Xuewen; Li, Wenzhi; Huang, Jian Yu; Provencio, Paula Polyak

    2014-05-01

    Undoped and indium (In)-doped lead telluride (PbTe) nanostructures were synthesized via solvothermal/hydrothermal route. The crystalline structure of the as-prepared undoped and In-doped PbTe samples was examined by X-ray diffraction (XRD) which indicated the formation of face-centered single-phase cubic crystal. A first principle calculation on indium doping shows that the indium atoms are more likely to replace lead (Pb) rather than to take the interstitial sites. Laser-induced breakdown spectroscopy (LIBS) analysis confirms that indium is incorporated into the PbTe matrix of the indium-doped PbTe samples. The effects of surfactant and synthesis temperature on the structure and morphology of the undoped PbTe were also investigated; it was found that PbTe nanostructures synthesized with the addition of surfactants exhibited uniform shapes and their size increased with the synthesis temperature.

  13. 15 CFR 744.10 - Restrictions on certain entities in Russia.

    Science.gov (United States)

    2010-01-01

    ... Russia. 744.10 Section 744.10 Commerce and Foreign Trade Regulations Relating to Commerce and Foreign... REGULATIONS CONTROL POLICY: END-USER AND END-USE BASED § 744.10 Restrictions on certain entities in Russia. (a) General prohibition. Certain entities in Russia are included in Supplement No. 4 to this part 744 (Entity...

  14. 12 CFR 911.6 - Persons and entities with access to unpublished information.

    Science.gov (United States)

    2010-01-01

    ... employee or agent, or any entity, including a supervised entity, Bank member, or government agency that... person or entity served with request. Unless the Finance Board has authorized in writing disclosure of the requested information: (1) A current or former Finance Board employee or agent or a supervised...

  15. 78 FR 30397 - Identification of Entity Pursuant to the Iranian Transactions and Sanctions Regulations and...

    Science.gov (United States)

    2013-05-22

    ... list of Specially Designated Nationals and Blocked Persons (``SDN List'') to identify this entity... Availability The SDN List and additional information concerning OFAC are available from OFAC's Web site ( www... Order and the ITSR, and updated the SDN List to identify this entity. The listing for this entity is as...

  16. Collaborative human-machine analysis to disambiguate entities in unstructured text and structured datasets

    Science.gov (United States)

    Davenport, Jack H.

    2016-05-01

    Intelligence analysts demand rapid information fusion capabilities to develop and maintain accurate situational awareness and understanding of dynamic enemy threats in asymmetric military operations. The ability to extract relationships between people, groups, and locations from a variety of text datasets is critical to proactive decision making. The derived network of entities must be automatically created and presented to analysts to assist in decision making. DECISIVE ANALYTICS Corporation (DAC) provides capabilities to automatically extract entities, relationships between entities, semantic concepts about entities, and network models of entities from text and multi-source datasets. DAC's Natural Language Processing (NLP) Entity Analytics model entities as complex systems of attributes and interrelationships which are extracted from unstructured text via NLP algorithms. The extracted entities are automatically disambiguated via machine learning algorithms, and resolution recommendations are presented to the analyst for validation; the analyst's expertise is leveraged in this hybrid human/computer collaborative model. Military capability is enhanced by these NLP Entity Analytics because analysts can now create/update an entity profile with intelligence automatically extracted from unstructured text, thereby fusing entity knowledge from structured and unstructured data sources. Operational and sustainment costs are reduced since analysts do not have to manually tag and resolve entities.

  17. 49 CFR 37.41 - Construction of transportation facilities by public entities.

    Science.gov (United States)

    2010-10-01

    ... public entities. 37.41 Section 37.41 Transportation Office of the Secretary of Transportation... transportation facilities by public entities. (a) A public entity shall construct any new facility to be used in providing designated public transportation services so that the facility is readily accessible to and usable...

  18. Colima: The eleventh entity most competitive of the country

    Directory of Open Access Journals (Sweden)

    José Manuel Orozco Plascencia

    2008-03-01

    Full Text Available According to the I Report of the State Competitiveness 2006, the State of Colima is considered to be the eleventh federal entity more competitive of the country. Number obtained in the favorable results in the national ranking of competitiveness, due to it got a third position to have with a System of Rights Reliable and Objective, besides it got three fifth positions: Sustainable Management of the Environment, Market of Efficient Factors and Precursor Sectors of the World Class, besides of a eighth position to count on a Dynamic Economic and Stables Indicators. Nevertheless, there are some indicators that showed unfavorable results for the entity, for instance, Colima got the 30th place in the factor of Achievement of the International Relations, the 27th position to count on a bad Political and Functional System, and the 24th place to have an Efficient and Effective Government. On average of the sectorial competitiveness, the Pharmaceutical and High-Tech sector holds the fifth position in the national ranking, in order to the priorities for the location of the business investment; the Manufactures are located in the sixth Place; the Textile sector in the eighth, and the more straggler ones like the Agribusiness and Tourism in the ninth position, respectively. Finally, the sensitivity of the investments above an increase of 10% relative to the 120 quantitative variables that revealed that Colima could pass from the eleventh to the third position, this like a result to increase its investment in 3,228 million of pesos for the entity, or increase in 30% the amount per capita for each member of the PEA, equivalent to 12,300 pesos average for employee.

  19. Customer and household matching: resolving entity identity in data warehouses

    Science.gov (United States)

    Berndt, Donald J.; Satterfield, Ronald K.

    2000-04-01

    The data preparation and cleansing tasks necessary to ensure high quality data are among the most difficult challenges faced in data warehousing and data mining projects. The extraction of source data, transformation into new forms, and loading into a data warehouse environment are all time consuming tasks that can be supported by methodologies and tools. This paper focuses on the problem of record linkage or entity matching, tasks that can be very important in providing high quality data. Merging two or more large databases into a single integrated system is a difficult problem in many industries, especially in the wake of acquisitions. For example, managing customer lists can be challenging when duplicate entries, data entry problems, and changing information conspire to make data quality an elusive target. Common tasks with regard to customer lists include customer matching to reduce duplicate entries and household matching to group customers. These often O(n2) problems can consume significant resources, both in computing infrastructure and human oversight, and the goal of high accuracy in the final integrated database can be difficult to assure. This paper distinguishes between attribute corruption and entity corruption, discussing the various impacts on quality. A metajoin operator is proposed and used to organize past and current entity matching techniques. Finally, a logistic regression approach to implementing the metajoin operator is discussed and illustrated with an example. The metajoin can be used to determine whether two records match, don't match, or require further evaluation by human experts. Properly implemented, the metajoin operator could allow the integration of individual databases with greater accuracy and lower cost.

  20. Extracting biomedical events from pairs of text entities.

    Science.gov (United States)

    Liu, Xiao; Bordes, Antoine; Grandvalet, Yves

    2015-01-01

    Huge amounts of electronic biomedical documents, such as molecular biology reports or genomic papers are generated daily. Nowadays, these documents are mainly available in the form of unstructured free texts, which require heavy processing for their registration into organized databases. This organization is instrumental for information retrieval, enabling to answer the advanced queries of researchers and practitioners in biology, medicine, and related fields. Hence, the massive data flow calls for efficient automatic methods of text-mining that extract high-level information, such as biomedical events, from biomedical text. The usual computational tools of Natural Language Processing cannot be readily applied to extract these biomedical events, due to the peculiarities of the domain. Indeed, biomedical documents contain highly domain-specific jargon and syntax. These documents also describe distinctive dependencies, making text-mining in molecular biology a specific discipline. We address biomedical event extraction as the classification of pairs of text entities into the classes corresponding to event types. The candidate pairs of text entities are recursively provided to a multiclass classifier relying on Support Vector Machines. This recursive process extracts events involving other events as arguments. Compared to joint models based on Markov Random Fields, our model simplifies inference and hence requires shorter training and prediction times along with lower memory capacity. Compared to usual pipeline approaches, our model passes over a complex intermediate problem, while making a more extensive usage of sophisticated joint features between text entities. Our method focuses on the core event extraction of the Genia task of BioNLP challenges yielding the best result reported so far on the 2013 edition.

  1. Named Entity Recognition in a Hungarian NL Based QA System

    Science.gov (United States)

    Tikkl, Domonkos; Szidarovszky, P. Ferenc; Kardkovacs, Zsolt T.; Magyar, Gábor

    In WoW project our purpose is to create a complex search interface with the following features: search in the deep web content of contracted partners' databases, processing Hungarian natural language (NL) questions and transforming them to SQL queries for database access, image search supported by a visual thesaurus that describes in a structural form the visual content of images (also in Hungarian). This paper primarily focuses on a particular problem of question processing task: the entity recognition. Before going into details we give a short overview of the project's aims.

  2. Localized cystic disease of the kidney: a rare entity.

    Science.gov (United States)

    Neyaz, Zafar; Kumar, Sunil; Lal, Hira; Kapoor, Rakesh

    2012-07-01

    Localized cystic disease of the kidney is a benign nonsurgical entity and presents with multiple cystic lesions in just one portion of the kidney or involves the entire one kidney. We report a case of localized cystic disease of the kidney in a 16 year-old-male. This patient underwent an ultrasound examination and incidentally found to have multiple cysts in the right kidney whereas the left kidney was normal. Diagnosis was confirmed by typical MRI findings, absence of any family history, normal results of urine analysis and renal function tests.

  3. Paragonimus westermani infection in lung: A confounding diagnostic entity

    Directory of Open Access Journals (Sweden)

    Shivani Kalhan

    2015-01-01

    Full Text Available Paragonimiasis is a food-borne parasitic zoonosis caused by the genus Paragonimus. Fresh water snails, crabs, and crayfish are the first and second intermediate hosts, respectively. Humans acquire this infection by ingesting uncooked/undercooked crustaceans. Laboratory diagnosis of Paragonimiasis is done by demonstration of ova in the sputum/feces/pleural fluid or by serology. A case of pulmonary Paragonimiasis is presented herewith; the patient having been diagnosed with pulmonary tuberculosis earlier. The aim of this presentation is to highlight this entity so that it is considered in the differential diagnosis in a case of hemoptysis.

  4. Pott’s Puffy Tumor: An Uncommon Clinical Entity

    Directory of Open Access Journals (Sweden)

    Phillip T. Suwan

    2012-01-01

    Full Text Available Although first described in 1760, Pott’s puffy tumor is a lesser known clinical entity. Often seen as a complication of frontal sinusitis, Pott’s is a frontal bone osteomyelitis with an associated subperiosteal abscess. Patients present with a fluctuant swelling of the scalp. The diagnosis is often confirmed with computed tomography (CT. Prompt surgical and medical treatments are the rule as there is the potential for significant morbidity if not quickly diagnosed and treated. Herein, we describe the presentation, diagnosis, and treatment of an 8-year-old female presenting with Pott’s puffy tumor.

  5. The general entity of life: a cybernetic approach.

    Science.gov (United States)

    Bielecki, Andrzej

    2015-06-01

    Life, not only in the well-known context of biochemical metabolism but also in the context of hypothetical life synthesized laboratorially or possibly found on other planets, is considered in this paper. The three-component information-energetic-structural irreducible processing in autonomous systems is the core of the proposed approach. The cybernetic organization of a general entity of life--the alivon--is postulated. The crucial properties of life and evolution are derived from the proposed approach. Information encoded in biological structures is also studied.

  6. Monoclonal gammopathy associated membranous glomerulonephritis: A rare entity

    Directory of Open Access Journals (Sweden)

    K K Gowda

    2015-01-01

    Full Text Available A 40-year-old male presented with nephrotic syndrome. Light microscopic analysis of the renal biopsy showed thickening of the glomerular capillary wall. Immunofluorescence examination revealed granular deposition of monoclonal immunoglobulin (Ig G3-kappa and complement C3 along the glomerular basement membrane. Electron microscopy showed subepithelial electron dense deposits, thus confirming membranous glomerulonephritis (MGN with monoclonal gammopathy. MGN with monoclonal gammopathy is an extremely rare but distinctive entity. This patient was treated with a combination of bortezomib, thalidomide and dexamethasone and showed partial remission of his nephrotic state and dysproteinemia.

  7. Is undifferentiated spondyloarthritis a discrete entity? A debate.

    Science.gov (United States)

    Deodhar, Atul; Miossec, Pierre; Baraliakos, Xenofon

    2018-01-01

    The concept of undifferentiated spondyloarthritis has been introduced recently to describe a clinical setting where the classical features of spondyloarthritis (SpA) are not fully present. Whether this is a discrete entity was the basis of a debate during the 4th International Congress on Controversies in Rheumatology & Autoimmunity held in Bologna, Italy 9-11 March 2017. The pro and con aspects of the debate are presented. The implications of the debate are important ranging from diagnostic aspects to consequences for the society and the payers. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Design of Multithreaded Software The Entity-Life Modeling Approach

    CERN Document Server

    Sandén, Bo I

    2011-01-01

    This book assumes familiarity with threads (in a language such as Ada, C#, or Java) and introduces the entity-life modeling (ELM) design approach for certain kinds of multithreaded software. ELM focuses on "reactive systems," which continuously interact with the problem environment. These "reactive systems" include embedded systems, as well as such interactive systems as cruise controllers and automated teller machines.Part I covers two fundamentals: program-language thread support and state diagramming. These are necessary for understanding ELM and are provided primarily for reference. P

  9. 75 FR 1699 - Addition of Certain Persons on the Entity List: Addition of Persons Acting Contrary to the...

    Science.gov (United States)

    2010-01-13

    ..., two Chinese entities; (c) By adding under Hong Kong, in alphabetical order, seven Hong Kong entities; (d) By adding under Malaysia, in alphabetical order, four Malaysian entities; (e) By adding under...

  10. Entity Framework 4.0 Recipes A Problem-solution Approach

    CERN Document Server

    Tenny, L

    2010-01-01

    Entity Framework 4.0 Recipes provides an exhaustive collection of ready-to-use code solutions for Microsoft's Entity Framework, Microsoft's vision for the future of data access. Entity Framework is a model-centric data access platform with an ocean of new concepts and patterns for developers to learn. With this book, you will learn the core concepts of Entity Framework through a broad range of clear and concise solutions to everyday data access tasks. Armed with this experience, you will be ready to dive deep into Entity Framework, experiment with new approaches, and develop ways to solve even

  11. FINANCIAL CONSOLIDATION OF THE ADMINISTRATIVE-TERRITORIAL ENTITY IN THE LIGHT OF DECENTRALIZATION

    Directory of Open Access Journals (Sweden)

    Tatiana MANOLE

    2017-02-01

    Full Text Available „Should we head towards ‘self-government’ required by many of the participants, would that be a selfgovernmentof the citizens or the elect representatives? Whatever would happen, decentralization is, ina way, the book of our society, a book in which we find its aspirations, discrepancies and questions…It is well led from above, but it is well administered from the bottom.”(Xavier Frège, Paris, 1986 This article presents the results of study regarding the decentralization process, which is currentlyunderway in the Republic of Moldova. The purpose of the study is to highlight the fundamental concept ofdecentralization, the areas of administrative decentralization, the forms of manifestation of financialdecentralization (fiscal decentralization and budget decentralization, to identify the priorities of thedecentralization process, and to establish the indicators for measuring the degree of decentralization. Inbase of the statistical analysis and synthesis method, it was determined the current state of the art in theadministrative-territorial entities in the course of the decentralization process in relation to the publicfinance management reform. It were formulate proposals to accelerate the process of financialdecentralization and self-government.

  12. Different Synthesis Protocols for Co3O4?CeO2 Catalysts?Part 1: Influence on the Morphology on the Nanoscale

    OpenAIRE

    Yang, Jingxia; Lukashuk, Liliana; Akbarzadeh, Johanna; St?ger-Pollach, Michael; Peterlik, Herwig; F?ttinger, Karin; Rupprechter, G?nther; Schubert, Ulrich

    2014-01-01

    Co3O4-modified CeO2 (Co/Ce 1:4) was prepared by a combination of sol?gel processing and solvothermal treatment. The distribution of Co was controlled by means of the synthesis protocol to yield three different morphologies, namely, Co3O4 nanoparticles located on the surface of CeO2 particles, coexistent Co3O4 and CeO2 nanoparticles, or Co oxide structures homogeneously distributed within CeO2. The effect of the different morphologies on the properties of Co3O4?CeO2 was investigated with regar...

  13. "Disease entity" as the key theoretical concept of medicine.

    Science.gov (United States)

    Hucklenbroich, Peter

    2014-12-01

    Philosophical debates about the concept of disease, particularly of mental disease, might benefit from reconsideration and a closer look at the established terminology and conceptual structure of contemporary medical pathology and clinical nosology. The concepts and principles of medicine differ, to a considerable extent, from the ideas and notions of philosophical theories of disease. In medical theory, the concepts of disease entity and pathologicity are, besides the concept of disease itself, of fundamental importance, and they are essentially connected to the concepts cause of disease or etiological factor, natural course or natural history of disease, and pathological disposition. It is the concept of disease entity that is of key importance for understanding medical pathology and theory of disease. Its central role is shown by a short reconstruction of its main features and its intrinsic connection to the concept of pathologicity. The meaning of pathologicity is elucidated by explicating the underlying criteria. © The Author 2014. Published by Oxford University Press, on behalf of the Journal of Medicine and Philosophy Inc. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  14. Aneurysmal Bone Cyst Of Pubic Ramus: A Rare Entity

    Directory of Open Access Journals (Sweden)

    Ashith Rao

    2013-10-01

    Full Text Available Introduction: Aneurysmal bone cyst is an expansile, lytic, multiloculated, fluid filled cavities which usually occurs in the metaphysis of the long bones. ABC of the pubic ramus is a rare entity. Case Report: We present a case of a 21 year old male who presented with a swelling of the right inguinal region which was gradually progressive. Radiologically, there was a lytic expansile lesion of the superior pubic ramus. A contrast computed tomography revealed multiloculated cystic cavities and histopathology confirmed the diagnosis of ABC. Surgical excision of the complete tumor by anterior approach was done. Till date (2 years since surgery patient has no recurrence. Conclusion: ABC of pubic ramus is a rare entity and other differentials should always be kept in mind with confirmation of diagnosis by histopathology. Treatment with surgical curettage and bone grafting the defect is curative in selective cases but in this case due to size and location excision is the choice of treatment. Keywords: Aneurysmal bone cyst, Pelvic bone, Pubic ramus, multiloculated.

  15. Intestinal Neuronal Dysplasia Type B in Adults: A Controversial Entity

    Directory of Open Access Journals (Sweden)

    Vasillis Vougas

    2014-01-01

    Full Text Available Intestinal neuronal dysplasia (IND is a well-defined entity which raises controversy among authors, described as a congenital malformation of gastrointestinal innervation and caused by dysplastic embryonal development of the enteric nervous system. It is potentially associated with mild and chronic gastrointestinal motility disturbances. IND is rarely reported in adults and especially elderly patients. The present study reports on the case of a 71-year-old man suffering from longstanding idiopathic constipation and who was misdiagnosed for more than 60 years, despite several hospital admissions and a sigmoidectomy in the meantime. On the last admission, the patient presented with megacolon, abdominal pain and X-ray finding of bowel obstruction. Due to massive large bowel dilatation, an exploratory laparotomy failed to reveal any obvious mechanical cause, and a subtotal colectomy and Hartmann's procedure was performed. Bowel continuity was performed 3 months later. Analysis of full-thickness biopsies revealed enlarged myenteric and submucosal neurons as well as an increased number of giant cells and increased acetylcholinesterase activity in the mucosa. The diagnosis of IND was established. The main diagnostic criteria, the underlining pathophysiology and the recommended therapeutic approach of this rare entity are extensively reviewed.

  16. Evaluating Word Representation Features in Biomedical Named Entity Recognition Tasks

    Directory of Open Access Journals (Sweden)

    Buzhou Tang

    2014-01-01

    Full Text Available Biomedical Named Entity Recognition (BNER, which extracts important entities such as genes and proteins, is a crucial step of natural language processing in the biomedical domain. Various machine learning-based approaches have been applied to BNER tasks and showed good performance. In this paper, we systematically investigated three different types of word representation (WR features for BNER, including clustering-based representation, distributional representation, and word embeddings. We selected one algorithm from each of the three types of WR features and applied them to the JNLPBA and BioCreAtIvE II BNER tasks. Our results showed that all the three WR algorithms were beneficial to machine learning-based BNER systems. Moreover, combining these different types of WR features further improved BNER performance, indicating that they are complementary to each other. By combining all the three types of WR features, the improvements in F-measure on the BioCreAtIvE II GM and JNLPBA corpora were 3.75% and 1.39%, respectively, when compared with the systems using baseline features. To the best of our knowledge, this is the first study to systematically evaluate the effect of three different types of WR features for BNER tasks.

  17. A Kernel-Based Approach for Biomedical Named Entity Recognition

    Directory of Open Access Journals (Sweden)

    Rakesh Patra

    2013-01-01

    Full Text Available Support vector machine (SVM is one of the popular machine learning techniques used in various text processing tasks including named entity recognition (NER. The performance of the SVM classifier largely depends on the appropriateness of the kernel function. In the last few years a number of task-specific kernel functions have been proposed and used in various text processing tasks, for example, string kernel, graph kernel, tree kernel and so on. So far very few efforts have been devoted to the development of NER task specific kernel. In the literature we found that the tree kernel has been used in NER task only for entity boundary detection or reannotation. The conventional tree kernel is unable to execute the complete NER task on its own. In this paper we have proposed a kernel function, motivated by the tree kernel, which is able to perform the complete NER task. To examine the effectiveness of the proposed kernel, we have applied the kernel function on the openly available JNLPBA 2004 data. Our kernel executes the complete NER task and achieves reasonable accuracy.

  18. Facile one-pot synthesis of highly monodisperse nickel microspheres with raised nickel dots and their adsorption performance for heavy metal ions.

    Science.gov (United States)

    Teng, Yue; Song, Le Xin; Liu, Wei; Zhao, Li; Xia, Juan; Wang, Qing Shan; Ruan, Mao Mao; Yang, Zun; Qian, Yong Xin

    2016-06-21

    This report describes the facile solvothermal synthesis of highly monodispersed nickel microspheres with surfaces uniformly covered by nickel dots. Synthesis parameters including reaction times and reagent concentrations significantly influence the microspheric particle characteristics. The novelty of the synthetic method in this work is twofold: first, the controlled synthesis of Ni metallic microspheres using ethylene glycol as the precursor of a reductant and urea as the origin of OH(-) has never been reported. Second, there are few studies on the construction of Ni microspheres covered by uniform Ni dots using a one-step solvothermal method. Importantly, the as-prepared Ni microspheres show an improved ability to remove Cd(2+) ions even at high concentrations in water and a unique adsorption isotherm having an increasing adsorption capacity for Cd(2+) ions. The presence of Ni dots was considered to play an important role in the onset of the adsorption process. We believe that this work opens up new and possibly exciting opportunities in the field of adsorption of heavy metal ions.

  19. A comparative study of magnetic properties of MnFe2O4 nanoparticles prepared by thermal decomposition and solvothermal methods

    Directory of Open Access Journals (Sweden)

    B Aslibeiki

    2017-09-01

    Full Text Available A comparative study of magnetic properties of MnFe2O4 ferrite nanoparticles prepared by two different methods has been reported. The first sample (S1 was synthesized by thermal decomposition of metal nitrates. And the second sample (S2 was prepared by solvothermal method using Tri-ethylene glycol (TEG. Magnetic hysteresis loops at 300 and 5 K; magnetization and AC susceptibility measurements versus temperature confirmed the effective role of TEG on the magnetic properties of nanoparticles. The results showed that, at 300 K the saturation magnetization (MS of S2 sample is 46% greater than that of S1 sample. At 5 K, the difference in MS of the samples raised to 60%. AC susceptibility measurements at different frequencies and also magnetization versus temperature under field cooling and zero field cooling processes revealed that, the TEG molecules influence the surface spins order of S2 sample. The sample S1 showed strongly interacting superspin glass state, while the sample S2 consists of weakly interacting superparamagnetic nanoparticles.

  20. A facile one-pot solvothermal method to produce superparamagnetic graphene-Fe3O4 nanocomposite and its application in the removal of dye from aqueous solution.

    Science.gov (United States)

    Wu, Qiuhua; Feng, Cheng; Wang, Chun; Wang, Zhi

    2013-01-01

    A superparamagnetic graphene-Fe(3)O(4) nanocomposite (G/Fe(3)O(4)) was synthesized by a facile one-pot solvothermal method. The nanocomposite G/Fe(3)O(4) prepared by the new method was firstly used as an adsorbent to remove dye for water pollution remediation. In comparison with G/Fe(3)O(4) prepared by the in situ chemical coprecipitation, the newly prepared G/Fe(3)O(4) had a higher adsorption efficiency for the dye. The adsorption characteristics of the nanocomposite adsorbent were examined using the organic dye pararosaniline as the adsorbate. The adsorption kinetics, adsorption capacity of the adsorbent, and the effect of the adsorbent dosage and solution pH on the removal efficiency of pararosaniline were investigated. The adsorption capacity of G/Fe(3)O(4) for pararosaniline was evaluated using the Freundlich and Langmuir adsorption isotherm models. The G/Fe(3)O(4) hybrid composite can be easily manipulated in magnetic field for desired separation, leading to an easy removal of the dye from polluted water. The G/Fe(3)O(4) hybrid composite would have a great potential in removing organic dyes from polluted water. Copyright © 2012 Elsevier B.V. All rights reserved.

  1. The effect of structural and optical properties on the photocatalytic efficiency of Zinc Sulphide nanoparticles obtained by hydro/solvothermal decomposition of Zinc N,N-diethyldithiocarbamate

    Science.gov (United States)

    Siqueira, G. O.; de Morais, E. C. R.; da Silva, H. V.; Abelenda, A.; González, J. C.; Porto, A. O.

    2017-06-01

    Cubic and hexagonal zinc sulphide nanoparticles were prepared by hydro/solvothermal decomposition of Zinc N,N-diethyldithiocarbamate by using different experimental conditions such as pH values, solvents and the presence of a particle stabilizer, sodium polyacrylate. The effect of these different experimental conditions on the microstructure and photocatalytical efficiency of ZnS was investigated in this work. Microstructural parameters, such as, apparent mean crystal size, microstrain and crystal size distribution were determined by analysis of experimental X-ray diffraction. Apparent mean crystal sizes were in the range of 6.5-44 nm and the lattice microstrain varied from 0.24% to 0%. Dimethylformamide showed to be more suitable than water to form small particles with a very narrow size distribution. The obtained optical band gaps and Urbach energies were in range of 3.32-3.60 eV and 0.09-0.15 eV, respectively. Photoluminescence spectra showed strong visible light emissions (green, blue and white) associated to the electronic levels introduced by the presence of superficial defects. The photocatalytic efficiency of these samples was investigated towards methylene blue degradation and a correlation between this efficiency and the PL intensity was observed. This correlation was associated to the formation of surface active centres at catalyst surfaces and the local potential fluctuations of valence and conduction bands.

  2. Solvothermal modification of BiOCl nanosheets with Bi nanoparticles using ascorbic acid as reductant and the superoxide radicals dominated photocatalytic performance

    Science.gov (United States)

    Cui, Zhankui; Gao, Keke; Ge, Suxiang; Fa, Wenjun

    2017-11-01

    BiOCl nanosheets were solvothermally modified with Bi nanoparticles (NPs) using ascorbic acid as the reductant. The structures of Bi/BiOCl composites were characterized by XRD, Raman spectroscopy, FTIR spectroscopy and SEM. The light absorption properties were measured by UV–vis–NIR spectroscopy. The photocatalytic performances were evaluated by photodegrading methyl orange (MO) and the photocatalytic mechanism was investigated using trapping experiments and a fluorescent probe method. The results show that Bi NPs are uniformly distributed on the surfaces of BiOCl nanosheets and the modification amount of Bi NPs could be well controlled because of the mild property of ascorbic acid as reducing agent. The photocatalytic activities for the composites are improved obviously and the best photocatalytic performance is obtained when the weight ratio of Bi and BiOCl is1:10 and the photochemical reaction rate is 3.5 times that of pure BiOCl nanosheets and 19.7 times of Bi powders. The enhanced photocatalytic efficiency is ascribed to the favorable formation of dominant \\cdot O2- radicals caused by the increased photoinduced electrons from both Bi NPs and BiOCl nanosheets.

  3. Solvent effects on microstructures and properties of three-dimensional hierarchical TiO2 microsphere structures synthesized via solvothermal approach

    Science.gov (United States)

    Xu, Shiping; Sun, Xiang; Gao, Yuan; Yue, Min; Yue, Qinyan; Gao, Baoyu

    2017-09-01

    One-step solvothermal method has been proved to be a simple and efficient route to synthesize three-dimensional (3D) hierarchical TiO2 microsphere structures, but discrepant properties of the solvent media had been claimed as the major factors determining microstructures and properties of the final products. In this study, several typical solvents, including alkane, aromatic hydrocarbons, halohydrocarbon, ketone, organic acid, mono- and dihydric alcohols, were selected to comprehensively investigate the effect of solvents on the morphology, crystal structure, specific surface area, porous property and light harvesting capability of the final products. According to the experimental results, a good interface separating titanium precursor with aqueous phase in the reaction solution, created by non-polar solvents, or polar solvents which are immiscible with titanium precursor, was the decisive factor for the formation of quasi-3D urchin-like TiO2 microspheres self-assembled from one-dimensional (1D) nanostructures, and concentrated H+ induced by organic acid medium was also helpful. Meanwhile, without the liquid-liquid interface or extremely low solution pH, anatase TiO2 sphere structures with big specific surface area comprising of nanoparticles or nanosheets would be formed, and performed well in photodegradation of pollutants in water.

  4. The kinetics of swelling in block copolymer thin films during ``solvo-microwave'' and solvo-thermal annealing: The effect of vapour pressure

    Science.gov (United States)

    Mokarian-Tabari, Parvanrh; Collins, Timothy; Cummins, Cian; Delgado Simão, Claudia; Sotomayor, Clivia; Morris, Michael A.

    2015-03-01

    Long annealing time associated with high chi block copolymers is a major disadvantage for their integration in industrial applications. Microwave-assisted microphase separation appears to offer considerable benefits in reducing annealing times for BCPs. However, despite the promise of this technique, little is known about the mechanism of how microwave irradiation might sponsor the molecular motion that accompanies microphase separation. In our earlier work we carried out an in situ temperature measurement during ``solvo-microwave'' annealing of poly(styrene-b-lactic acid) (PS- b-PLA) in presence of THF and also in the conventional oven. Comparing the results indicated that vapour pressure of THF might have a major role to achieve fast self- assembly (60 seconds) in PS- b-PLA film. Here, we study the kinetics of swelling by monitoring the pressure through in situ pressure experiments during ``solvo-microwave'' and solvo-thermal annealing. The preliminary data suggest that the rate at which the THF pressure increases is the key factor. This suggests that kinetics, i.e., the rate of film swelling and diffusion, affects the order and the coherence length of the pattern. We estimated the defect density in the patterns by our recently developed defect analysis software.

  5. Solvothermal fabrication of activated semi-coke supported TiO2-rGO nanocomposite photocatalysts and application for NO removal under visible light

    Science.gov (United States)

    Yang, Weiwei; Li, Chunhu; Wang, Liang; Sun, ShengNan; Yan, Xin

    2015-10-01

    The photocatalysts of activated semi-coke supported TiO2-rGO nanocomposite (TiO2-rGO/ASC) with different contents of reduced graphene oxide were fabricated by one-step solvothermal method for NO removal under visible light irradiation. It was confirmed that 8% content of reduced graphene oxide presented the best NO photooxidation performance under visible light irradiation at 70 °C with 350-400 mg/m3 NO,5% O2 and 5% relative humidity. The reasons for improved activity were discussed, alloyed with the mechanism of producing CO. Detailed structural information of TiO2-rGO/ASC photocatalysts was characterized by scanning electron microscope (SEM), energy dispersive X-ray Spectroscopy (EDX), X-ray diffraction analysis (XRD), UV-Vis diffuse reflectance spectra (UV-Vis DRS) and photoluminescence (PL), which indicated that the introduction of rGO was responsible for well dispersion, smaller crystalline size, red shift of absorption band and suppressing quick photo-induced charges recombination of TiO2-rGO/ASC photocatalysts. Optimization of operational parameters with 70 °C, 8% O2 and 8% relative humidity were also obtained. Deactivation of TiO2-rGO/ASC photocatalysts for NO removal was investigated by Fourier-transform infrared (FTIR) analysis. Regeneration experiments showed that thermal vapor regeneration would be optimal method owing to excellent regenerative capacity and inexpensive procedure.

  6. Effects of non-polar solvent on the morphology and property of three-dimensional hierarchical TiO2 nanostructures by one-step solvothermal route

    Science.gov (United States)

    Zhou, Yi; Wu, Hongyan; Zhong, Xian; Liu, Ce

    2014-07-01

    Three-dimensional (3D) hierarchical rutile TiO2 microspheres composed of nanorods with diameter of several-tens of nanometers, with different morphologies and with average size ranging from 1.3 to 1.8 μm, were successfully synthesized through a surfactant-free solvothermal route. The effects of the solvents n-hexane, chloroform, and cyclohexane on the microstructures of 3D hierarchical TiO2 nanostructures were investigated. Results of scanning electron microscopy showed that 3D sea-urchin like hierarchical TiO2 composed of nanorods with a diameter of 10 nm can only be prepared in the cyclohexane-water system. The growth mechanism of 3D sea-urchin like hierarchical TiO2 composed of numerous nanorods was further examined and found to differ from the well-known "growth → assembly" mode. The effects of surface tension and polarity of solvents on the morphology and crystal strength of 3D hierarchical TiO2 nanostructure were also investigated. In addition, the prepared 3D sea-urchin like hierarchical TiO2 showed highest photocatalytic activity compared with other 3D hierarchical TiO2 nanostructures in this study and Degussa P25 for the degradation of Rhodamine B solution under UV light irradiation, which could be attributed to its special hierarchical superstructure, the increase of surface catalytic sites and its special composition units.

  7. Sheet-on-sheet chrysanthemum-like C/FeS microspheres synthesized by one-step solvothermal method for high-performance sodium-ion batteries

    Science.gov (United States)

    Cao, Zhenjiang; Song, Huaihe; Cao, Bin; Ma, Jing; Chen, Xiaohong; Zhou, Jisheng; Ma, Zhaokun

    2017-10-01

    Chrysanthemum-like carbon/FeS microspheres (CL-C/FeS) are prepared from a one-step solvothermal method. The morphology and structure of the CL-C/FeS are characterized by X-ray diffraction, scanning electron microscopy and high-resolution transmission electron microscope. We note that the prepared CL-C/FeS microspheres exhibit the average diameter of 15 μm and possess a sheet-on-sheet structure. FeS nanosheets are stacked on the carbon sheets to form a 2D sheet-on-sheet structure, these 2D C/FeS nanosheets are self-assembled to form a 3D chrysanthemum-like morphology. Due to the unique structure, CL-C/FeS microspheres show the excellent sodium-storage performance of 500 mAh g-1 at 0.2 A g-1 and 260 mAh g-1 at 1 A g-1, which are higher than those of most reported values. Therefore, the CL-C/FeS with appropriate structure is expected to be a competitive choice for anode materials for sodium ion batteries.

  8. Effect of Mo and Co loading in HDS catalysts supported on solvo-thermally treated ZrO{sub 2}-TiO{sub 2} mixed oxides

    Energy Technology Data Exchange (ETDEWEB)

    Escobar, Jose; Cortes, Maria A. [Instituto Mexicano del Petroleo, Prog. de Ing. Molecular, Eje Central Lazaro Cardenas 152, Col. San Bartolo Atepehuacan, Gustavo A. Madero, Mexico, D.F. 07730 (Mexico); Barrera, Maria C. [Instituto Mexicano del Petroleo, Prog. de Ing. Molecular, Eje Central Lazaro Cardenas 152, Col. San Bartolo Atepehuacan, Gustavo A. Madero, Mexico, D.F. 07730 (Mexico); Universidad Autonoma Metropolitana-Iztapalapa, San Rafael Atlixco 186, Col. Vicentina, Iztapalapa, Mexico, D.F. 09340 (Mexico); Reyes, Jose A. De Los [Universidad Autonoma Metropolitana-Iztapalapa, San Rafael Atlixco 186, Col. Vicentina, Iztapalapa, Mexico, D.F. 09340 (Mexico); Santes, Victor [CIIEMAD-IPN, Calle 30 de Junio de 1520, Col. Barrio la Laguna Ticoman, Gustavo A. Madero, Mexico, D.F. 07340 (Mexico); Gomez, Elizabeth [Instituto de Quimica-UNAM, Circuito Exterior, Ciudad Universitaria, Mexico, D.F. 04510 (Mexico); Pacheco, Jose G. [Division Academica de Ciencias Basicas, Universidad Juarez Autonoma de Tabasco, Km. 1, Carretera Cunduacan-Jalpa de Mendez, Cunduacan, Tabasco (Mexico)

    2008-04-15

    Molybdenum (at 2.8, 3.3, 4.0 and 4.7 atoms nm{sup -2}) and cobalt (Co/(Co + Mo) ratios of 0.3, 0.4 and 0.5) were impregnated on wide-pore ZrO{sub 2}-TiO{sub 2} mixed oxides (30-70) prepared with solvo-thermal treatment (80 C, 1 day). Materials characterization comprised N{sub 2} physisorption, XRD, thermal analyses, and UV-vis DRS, Raman, and IR spectroscopies. For impregnated dried materials (non-calcined) at concentrations beyond 3.3 atom nm{sup -2} and activated by sulfiding (H{sub 2}S/H{sub 2}, 400 C) no further improvement in activity in dibenzothiophene (DBT) hydrodesulfurization (HDS) (at 5.59 MPa, T = 320 C) was observed. Thus, monolayer Mo dispersion was assumed at that content. The aforementioned formulation was chosen to be promoted by Co at different concentrations, the maximum HDS activity being found for sulfided catalyst with Co/(Co + Mo) = 0.4. Nevertheless, the promotion observed by Co addition was small (by a factor of {proportional_to}3.2). The activity trends observed in the DBT HDS were well confirmed in the hydrotreatment of a real feedstock (straight-run gasoil). Dibenzothiophene reliably represented the behavior of organo-sulfur compounds present in the middle distillate, at the reaction conditions used in this study where sterically hindered compounds remained unreacted in the hydrotreated gasoil. (author)

  9. Microwave-assisted one-pot synthesis of ring-fused aminals under catalyst- and solvent-free conditions

    Science.gov (United States)

    Heterocyclic compounds hold a special place in drug discovery and variety of techniques such as combinatorial synthesis, parallel synthesis, and automated library production to increase the output of these entities has been developed. Although most of these techniques are rapid a...

  10. Gliomatosis cerebri: no evidence for a separate brain tumor entity.

    Science.gov (United States)

    Herrlinger, Ulrich; Jones, David T W; Glas, Martin; Hattingen, Elke; Gramatzki, Dorothee; Stuplich, Moritz; Felsberg, Jörg; Bähr, Oliver; Gielen, Gerrit H; Simon, Matthias; Wiewrodt, Dorothee; Schabet, Martin; Hovestadt, Volker; Capper, David; Steinbach, Joachim P; von Deimling, Andreas; Lichter, Peter; Pfister, Stefan M; Weller, Michael; Reifenberger, Guido

    2016-02-01

    Gliomatosis cerebri (GC) is presently considered a distinct astrocytic glioma entity according to the WHO classification for CNS tumors. It is characterized by widespread, typically bilateral infiltration of the brain involving three or more lobes. Genetic studies of GC have to date been restricted to the analysis of individual glioma-associated genes, which revealed mutations in the isocitrate dehydrogenase 1 (IDH1) and tumor protein p53 (TP53) genes in subsets of patients. Here, we report on a genome-wide analysis of DNA methylation and copy number aberrations in 25 GC patients. Results were compared with those obtained for 105 patients with various types of conventional, i.e., non-GC gliomas including diffuse astrocytic gliomas, oligodendrogliomas and glioblastomas. In addition, we assessed the prognostic role of methylation profiles and recurrent DNA copy number aberrations in GC patients. Our data reveal that the methylation profiles in 23 of the 25 GC tumors corresponded to either IDH mutant astrocytoma (n = 6), IDH mutant and 1p/19q codeleted oligodendroglioma (n = 5), or IDH wild-type glioblastoma including various molecular subgroups, i.e., H3F3A-G34 mutant (n = 1), receptor tyrosine kinase 1 (RTK1, n = 4), receptor tyrosine kinase 2 (classic) (RTK2, n = 2) or mesenchymal (n = 5) glioblastoma groups. Two tumors showed methylation profiles of normal brain tissue due to low tumor cell content. While histological grading (WHO grade IV vs. WHO grade II and III) was not prognostic, the molecular classification as classic/RTK2 or mesenchymal glioblastoma was associated with worse overall survival. Multivariate Cox regression analysis revealed MGMT promoter methylation as a positive prognostic factor. Taken together, DNA-based large-scale molecular profiling indicates that GC comprises a genetically and epigenetically heterogeneous group of diffuse gliomas that carry DNA methylation and copy number profiles closely matching the common molecularly

  11. Bayesian Modeling of Temporal Coherence in Videos for Entity Discovery and Summarization.

    Science.gov (United States)

    Mitra, Adway; Biswas, Soma; Bhattacharyya, Chiranjib

    2017-03-01

    A video is understood by users in terms of entities present in it. Entity Discovery is the task of building appearance model for each entity (e.g., a person), and finding all its occurrences in the video. We represent a video as a sequence of tracklets, each spanning 10-20 frames, and associated with one entity. We pose Entity Discovery as tracklet clustering, and approach it by leveraging Temporal Coherence (TC): the property that temporally neighboring tracklets are likely to be associated with the same entity. Our major contributions are the first Bayesian nonparametric models for TC at tracklet-level. We extend Chinese Restaurant Process (CRP) to TC-CRP, and further to Temporally Coherent Chinese Restaurant Franchise (TC-CRF) to jointly model entities and temporal segments using mixture components and sparse distributions. For discovering persons in TV serial videos without meta-data like scripts, these methods show considerable improvement over state-of-the-art approaches to tracklet clustering in terms of clustering accuracy, cluster purity and entity coverage. The proposed methods can perform online tracklet clustering on streaming videos unlike existing approaches, and can automatically reject false tracklets. Finally we discuss entity-driven video summarization- where temporal segments of the video are selected based on the discovered entities, to create a semantically meaningful summary.

  12. Effect of oxidation degree on the synthesis and adsorption property of magnetite/graphene nanocomposites

    Science.gov (United States)

    Luo, Kun; Mu, Yuanying; Wang, Peng; Liu, Xiaoteng

    2015-12-01

    A facile approach is demonstrated to synthesize a series of magnetite/graphene nanocomposites by solvothermal method, which can be easily collected after removal of pollutants without secondary pollution of graphene powders. Raman and FT-IR analyses show that the reduction of the mixing vapor of ammonia and hydrazine at different reaction periods generates the discrepancy of oxidation degree for reduced graphene oxide (rGO), which can be kept after the solvothermal synthesis of Fe3O4/rGO nanocomposites. Batch adsorption experiments indicate that the nanocomposite with maximum oxidation degree of rGO presents the largest magnetization of 35.4 emu g-1 and adsorption capacity of 59.2 mg g-1 for Cu2+, while the one with minimum oxidation degree exhibits the strongest adsorption of 39.0 mg g-1 for methylene blue accompanied with appropriate magnetization of 9.0 emu g-1, and only 23% of initial capacity was lost after seven recycling use. The adsorption kinetics of the both composites follows the pseudo-second-order model, suggestive of physical and chemical interactions between the pollutants and adsorbent. The results suggest that the oxidation degree of the rGO substrate can apparently influence both the structure and the adsorbing behavior of Fe3O4/rGO nanocomposites, which allows the control over the adsorbent performance according to the pollutant of interest.

  13. Enhancement of chemical entity identification in text using semantic similarity validation.

    Directory of Open Access Journals (Sweden)

    Tiago Grego

    Full Text Available With the amount of chemical data being produced and reported in the literature growing at a fast pace, it is increasingly important to efficiently retrieve this information. To tackle this issue text mining tools have been applied, but despite their good performance they still provide many errors that we believe can be filtered by using semantic similarity. Thus, this paper proposes a novel method that receives the results of chemical entity identification systems, such as Whatizit, and exploits the semantic relationships in ChEBI to measure the similarity between the entities found in the text. The method assigns a single validation score to each entity based on its similarities with the other entities also identified in the text. Then, by using a given threshold, the method selects a set of validated entities and a set of outlier entities. We evaluated our method using the results of two state-of-the-art chemical entity identification tools, three semantic similarity measures and two text window sizes. The method was able to increase precision without filtering a significant number of correctly identified entities. This means that the method can effectively discriminate the correctly identified chemical entities, while discarding a significant number of identification errors. For example, selecting a validation set with 75% of all identified entities, we were able to increase the precision by 28% for one of the chemical entity identification tools (Whatizit, maintaining in that subset 97% the correctly identified entities. Our method can be directly used as an add-on by any state-of-the-art entity identification tool that provides mappings to a database, in order to improve their results. The proposed method is included in a freely accessible web tool at www.lasige.di.fc.ul.pt/webtools/ice/.

  14. Dysphonic Occupational Syndrome: New Aspects of this Nosological Entity

    Directory of Open Access Journals (Sweden)

    Pontes, Paulo

    2010-09-01

    Full Text Available Introduction: Teachers often have vocal disorders that benefit from preventive measures. Objective: To determine the prevalence of the syndrome in dysphonic teachers and check the evolution of this index with the techniques of primary prevention. Method: We performed a cross-sectional study of teachers in two different periods: in the first 101 teachers and participated in phase 2, 148 teachers. These two groups was administered the questionnaire prepared by the tripartite commission on regulation of the professional voice. Results: The prevalence of the syndrome dysphonic in the first phase was 70.3%, while the second stage was 57.59%. Conclusion: 1st dysphonic the prevalence of the syndrome was significantly decreased with the implementation of preventive and medical control of work organization. 2nd dysphonic syndrome is a new nosological entity. Cross-sectional epidemiological study. Study series.

  15. Sub-micrometer fluidic channel for measuring photon emitting entities

    Science.gov (United States)

    Stavis, Samuel M; Edel, Joshua B; Samiee, Kevan T; Craighead, Harold G

    2014-11-18

    A nanofluidic channel fabricated in fused silica with an approximately 500 nm square cross section was used to isolate, detect and identify individual quantum dot conjugates. The channel enables the rapid detection of every fluorescent entity in solution. A laser of selected wavelength was used to excite multiple species of quantum dots and organic molecules, and the emission spectra were resolved without significant signal rejection. Quantum dots were then conjugated with organic molecules and detected to demonstrate efficient multicolor detection. PCH was used to analyze coincident detection and to characterize the degree of binding. The use of a small fluidic channel to detect quantum dots as fluorescent labels was shown to be an efficient technique for multiplexed single molecule studies. Detection of single molecule binding events has a variety of applications including high throughput immunoassays.

  16. Evolving concepts of chronic traumatic encephalopathy as a neuropathological entity.

    Science.gov (United States)

    Ling, H; Neal, J W; Revesz, T

    2017-10-01

    Chronic traumatic encephalopathy (CTE) is a long-term neurodegenerative consequence of repetitive head impacts which can only be definitively diagnosed in post-mortem. Recently, the consensus neuropathological criteria for the diagnosis of CTE was published requiring the presence of the accumulation of abnormal tau in neurons and astroglia distributed around small blood vessels at the depths of cortical sulci in an irregular pattern as the mandatory features. The clinical diagnosis and antemortem prediction of CTE pathology remain challenging if not impossible due to the common co-existing underlying neurodegenerative pathologies and the lack of specific clinical pointers and reliable biomarkers. This review summarizes the historical evolution of CTE as a neuropathological entity and highlights the latest advances and future directions of research studies on the topic of CTE. © 2017 British Neuropathological Society.

  17. Clinicopathologic diagnostic criteria of an enigmatic entity: Proliferative verrucous leukoplakia

    Directory of Open Access Journals (Sweden)

    Ramnarayan Belur Krishna Prasad

    2015-01-01

    Full Text Available Proliferative verrucous leukoplakia (PVL is a rare, unique type of oral leukoplakia, which is enigmatic in etiology and behaves in a far more aggressive fashion than other forms of leukoplakia. Diagnosis is often late with the disease in an advanced stage when it is especially refractory to treatment. There are no definite criteria that dictate how extensive the leukoplakic changes should be, how many or which oral subsites should be involved, or how many recurrences should have occurred, in order to qualify for the diagnosis of PVL. The lack of definitive diagnostic criteria is the prime reason for PVL not being treated appropriately and in a timely fashion, thereby leading to the very concept of PVL being questioned. This article discusses the various clinicopathologic diagnostic criteria for this enigmatic entity and also reports a case of PVL in a 73-year-old female.

  18. SALES BUDGET - MANAGEMENT TOOL IN BUSINESS BACKGROUND ENTITY

    Directory of Open Access Journals (Sweden)

    Cristina-Otilia, ȚENOVICI

    2014-11-01

    Full Text Available Budget as a management tool is used to size the activity of forecasting the financial and accounting terms and in terms of economic efficiency, the allocation and use of resources to an entity in a particular reporting period, that aims to achieve the necessary expenses and income achieved, establishing this and the powers and responsibilities relating to the efficient use of these resources. Sales budgeting should be given special attention given the correlation and the influence of these predictions with other budgets namely production budget; supplies budget; investment budget; budget overheads; treasury budget. There should be understood that estimates of other budgets are not related or that there are no dependencies between them.

  19. The environment ontology: contextualising biological and biomedical entities

    Science.gov (United States)

    2013-01-01

    As biological and biomedical research increasingly reference the environmental context of the biological entities under study, the need for formalisation and standardisation of environment descriptors is growing. The Environment Ontology (ENVO; http://www.environmentontology.org) is a community-led, open project which seeks to provide an ontology for specifying a wide range of environments relevant to multiple life science disciplines and, through an open participation model, to accommodate the terminological requirements of all those needing to annotate data using ontology classes. This paper summarises ENVO’s motivation, content, structure, adoption, and governance approach. The ontology is available from http://purl.obolibrary.org/obo/envo.owl - an OBO format version is also available by switching the file suffix to “obo”. PMID:24330602

  20. CONCEPTUAL AND ACCOUNTING ASPECTS RELATING CONSTRUCTION CONTRACTS IN PUBLIC ENTITIES

    Directory of Open Access Journals (Sweden)

    Ţenovici Cristina Otilia

    2013-04-01

    Full Text Available Subsequent to the nature of activities performed in construction contracts, the date on which contract execution begins and the date of its completion generate two major issues in accountancy. The former issue occurs as a result of the fact that most construction contracts concluded by public sector entities do not specify the value of revenues under the contracts and accountancy therefore must find solutions for the way to allocate contract costs for the reporting periods of time when work was rendered and related expenses were recognized. The latter issue occurs when construction contracts were concluded on a commercial or non-commercial basis while recuperating partial or total costs, an issue which accounting has to settle in relation with the allocation of contract revenues and contract costs of reporting periods during which work was performed.

  1. Papillary tumor of pineal region: A rare entity

    Directory of Open Access Journals (Sweden)

    Meena Patil

    2013-01-01

    Full Text Available Pineal tumors comprise 0.4-1.0% of intracranial space occupying lesions in adults. Papillary tumor of pineal region (PTPR is a very rare entity. It has been newly described in WHO 2007 classification of brain tumors. Only a few case reports are available in the literature. We report a case of a 60-year-old female presenting with headache, giddiness and reduced vision. Imaging studies showed a pineal mass with areas of hemorrhage. All ventricles were normal. There was a past history of a pineal gland tumor excised 2 years ago. This case is being reported for its rarity and aggressiveness in the form of recurrence. Limited/available immunohistochemistry workup has been done.

  2. Unexpected Perinatal Loss versus Sids-a Common Neuropathologic Entity

    Science.gov (United States)

    Matturri, Luigi; Mauri, Maria; Elena Ferrero, Maria; Lavezzi, Anna Maria

    2008-01-01

    Objective: To evaluate the involvement of alterations of the central autonomic nervous system, particularly of the brainstem and cerebellum, in a wide set of victims of sudden and unexplained perinatal and infant death. Material and Methods: The study population consisted of 63 stillbirths, 28 neonatal deaths and 140 suspected SIDS. The victims were subjected to in-depth anatomopathological examination following appropriate guidelines. The protocol included, in particular, the histological evaluation on serial sections of the cardiorespiratory autonomic nervous system. Results: A diagnosis of “unexplained death” was established for 217 of the 231 victims (59 stillbirths, 28 newborns and 130 SIDS). In a very high percentage of these deaths (84%) we observed one or more anomalies of the nuclei and/or structures of the brainstem and cerebellum related to vital functions. Conclusion: Unexpected perinatal loss should not be regarded as a separate entity from SIDS, given the common neuropathological substrates. PMID:19018308

  3. Patellar chondral defects: a review of a challenging entity.

    Science.gov (United States)

    Mouzopoulos, George; Borbon, Carlo; Siebold, Rainer

    2011-12-01

    The aim of this study was to perform a review of the management of patellar cartilage defects, identify prognostic factors for better clinical outcomes, and propose a treatment algorithm of this challenging entity. We conducted a review of multiple databases, evaluating the clinical outcomes after patellar cartilage lesion treatment. Because of the heterogeneity of data, a meta-analysis could not be performed. Twelve studies were identified for inclusion. Based on the clinical outcomes of these studies, a treatment algorithm was proposed. The clinical outcomes after patellar cartilage defects repair depend on the location and size of the articular defect, the age of the patient, the successful reconstruction of the patellar ridge, the repair of extensor mechanism malalignment, and the coexistence of chondromalacia. The optimal treatment for cartilaginous defects of the patella is still elusive. More prospective studies are needed, in order to identify which techniques are cost-effective especially on a long-term basis.

  4. A Chinese Named Entity Recognition System with Neural Networks

    Directory of Open Access Journals (Sweden)

    Yi Hui-Kang

    2017-01-01

    Full Text Available Named entity recognition (NER is a typical sequential labeling problem that plays an important role in natural language processing (NLP systems. In this paper, we discussed the details of applying a comprehensive model aggregating neural networks and conditional random field (CRF on Chinese NER tasks, and how to discovery character level features when implement a NER system in word level. We compared the difference between Chinese and English when modeling the character embeddings. We developed a NER system based on our analysis, it works well on the ACE 2004 and SIGHAN bakeoff 2006 MSRA dataset, and doesn’t rely on any gazetteers or handcraft features. We obtained F1 score of 82.3% on MSRA 2006.

  5. Isolated nonpulsatile enophthalmos in neurofibromatosis: An uncommon entity

    Directory of Open Access Journals (Sweden)

    Swati Singh

    2017-01-01

    Full Text Available Isolated enophthalmos is a rarely observed entity in neurofibromatosis (NF. A 12-year-old male presented with right lower eyelid fat prolapse and enophthalmos for the past 7 years. There was no history of antecedent trauma/surgery. Computed tomography of orbit revealed an ill-defined intraconal hyperdense lesion located between lateral and inferior rectus along with an enlarged inferior orbital fissure (IOF. Superior orbital fissure was minimally widened without prolapse of any intracranial contents. Excision biopsy along with repair of widened IOF was performed through inferior transconjunctival route. Histopathology was suggestive of plexiform neurofibroma with positivity for S-100 and epithelial membrane antigen. No associated cutaneous lesions were present. Nonpulsatile enophthalmos with eyelid fat prolapse can be a presenting sign of NF.

  6. The environment ontology: contextualising biological and biomedical entities.

    Science.gov (United States)

    Buttigieg, Pier Luigi; Morrison, Norman; Smith, Barry; Mungall, Christopher J; Lewis, Suzanna E

    2013-12-11

    As biological and biomedical research increasingly reference the environmental context of the biological entities under study, the need for formalisation and standardisation of environment descriptors is growing. The Environment Ontology (ENVO; http://www.environmentontology.org) is a community-led, open project which seeks to provide an ontology for specifying a wide range of environments relevant to multiple life science disciplines and, through an open participation model, to accommodate the terminological requirements of all those needing to annotate data using ontology classes. This paper summarises ENVO's motivation, content, structure, adoption, and governance approach. The ontology is available from http://purl.obolibrary.org/obo/envo.owl - an OBO format version is also available by switching the file suffix to "obo".

  7. Cytomorphology of unusual infectious entities in the Pap test

    Science.gov (United States)

    Khalbuss, Walid E.; Michelow, Pam; Benedict, Cynthia; Monaco, Sara E.; Pantanowitz, Liron

    2012-01-01

    Rare entities in the Pap test, including neoplastic and non-neoplastic conditions, pose challenges due to their infrequent occurrence in the daily practice of cytology. Furthermore, these conditions give rise to important diagnostic pitfalls. Infections such as tuberculosis cervicitis may be erroneously diagnosed as carcinoma, whereas others, such as schistosomiasis, are associated with squamous cell carcinoma. These cases include granuloma inguinale (donovanosis), tuberculosis, coccidioidomycosis, schistosomiasis, taeniasis, and molluscum contagiosum diagnosed in Pap tests. Granuloma inguinale shows histiocytes that contain intracytoplasmic bacteria (Donovan bodies). Tuberculosis is characterized by necrotizing granulomatous inflammation with Langhans-multinucleated giant cells. Coccidioidomycosis may show large intact or ruptured fungal spherules associated with endospores. Schistosoma haematobium is diagnosed by finding characteristic ova with a terminal spine. Molluscum contagiosum is characterized by the appearance of squamous cells with molluscum bodies. This article reviews the cytomorphology of selected rare infections and focuses on their cytomorphology, differential diagnosis, and role of ancillary diagnostic studies. PMID:22919422

  8. Cytomorphology of unusual infectious entities in the Pap test

    Directory of Open Access Journals (Sweden)

    Walid E Khalbuss

    2012-01-01

    Full Text Available Rare entities in the Pap test, including neoplastic and non-neoplastic conditions, pose challenges due to their infrequent occurrence in the daily practice of cytology. Furthermore, these conditions give rise to important diagnostic pitfalls. Infections such as tuberculosis cervicitis may be erroneously diagnosed as carcinoma, whereas others, such as schistosomiasis, are associated with squamous cell carcinoma. These cases include granuloma inguinale (donovanosis, tuberculosis, coccidioidomycosis, schistosomiasis, taeniasis, and molluscum contagiosum diagnosed in Pap tests. Granuloma inguinale shows histiocytes that contain intracytoplasmic bacteria (Donovan bodies. Tuberculosis is characterized by necrotizing granulomatous inflammation with Langhans-multinucleated giant cells. Coccidioidomycosis may show large intact or ruptured fungal spherules associated with endospores. Schistosoma haematobium is diagnosed by finding characteristic ova with a terminal spine. Molluscum contagiosum is characterized by the appearance of squamous cells with molluscum bodies. This article reviews the cytomorphology of selected rare infections and focuses on their cytomorphology, differential diagnosis, and role of ancillary diagnostic studies.

  9. Hypertrophic cardiomyopathy and ultra-endurance running - two incompatible entities?

    Directory of Open Access Journals (Sweden)

    Wilson Mathew G

    2011-11-01

    Full Text Available Abstract Regular and prolonged exercise is associated with increased left ventricular wall thickness that can overlap with hypertrophic cardiomyopathy (HCM. Differentiating physiological from pathological hypertrophy has important implications, since HCM is the commonest cause of exercise-related sudden cardiac death in young individuals. Most deaths have been reported in intermittent 'start-stop' sports such as football (soccer and basketball. The theory is that individuals with HCM are unable to augment stroke volume sufficiently to meet the demands of endurance sports and are accordingly 'selected-out' of participation in such events. We report the case of an ultra-endurance athlete with 25 years of > 50 km competitive running experience, with genetically confirmed HCM; thereby demonstrating that these can be two compatible entities.

  10. Hypertrophic cardiomyopathy and ultra-endurance running - two incompatible entities?

    Science.gov (United States)

    Wilson, Mathew G; Chandra, Navin; Papadakis, Michael; O'Hanlon, Rory; Prasad, Sanjay K; Sharma, Sanjay

    2011-11-29

    Regular and prolonged exercise is associated with increased left ventricular wall thickness that can overlap with hypertrophic cardiomyopathy (HCM). Differentiating physiological from pathological hypertrophy has important implications, since HCM is the commonest cause of exercise-related sudden cardiac death in young individuals. Most deaths have been reported in intermittent 'start-stop' sports such as football (soccer) and basketball. The theory is that individuals with HCM are unable to augment stroke volume sufficiently to meet the demands of endurance sports and are accordingly 'selected-out' of participation in such events. We report the case of an ultra-endurance athlete with 25 years of > 50 km competitive running experience, with genetically confirmed HCM; thereby demonstrating that these can be two compatible entities.

  11. The Study of Graininess for Tibetan Named Entity Recognition

    Directory of Open Access Journals (Sweden)

    Liu Fei-Fei

    2017-01-01

    Full Text Available Tibetan named entity recognition (NER, which is a fundamental part in Tibetan natural language processing, is the important subtask of Information extraction. In this paper, we surveyed the methods, effect and problems of Tibetan NER. And we discussed which kind of tokens that should be taken as the graininess for Tibetan NER task. The paper used two kinds of different graininess in a comparative experiment for Tibetan person names, location names and organization names, based on syllables, or based on words. From the result, we know that the person names based on syllable have better result than that based on words. Location names have small difference while species differ. But the organization names are more suitable based on words.

  12. 2016 in review: FDA approvals of new molecular entities.

    Science.gov (United States)

    Griesenauer, Rebekah H; Kinch, Michael S

    2017-11-01

    An overview of drugs approved by FDA in 2016 reveals dramatic disruptions in long-term trends. The number of new molecular entities (NMEs) dropped, reflecting the lowest rate of small-molecule approvals observed in almost five decades. In addition, the pace of industry consolidation slowed substantially. The impact of mergers and acquisitions decreased the total number of organizations with past approval experience and continued research and development (R&D) activities to 102, divided evenly between more established pharmaceutical and newer biotechnology companies. Despite these substantial differences, the industry continued to pursue regulatory incentives, as evidenced by a continued increase in the fraction of NMEs approved using an orphan or priority designation, and almost all oncology drugs approved in 2016 utilized these mechanisms. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. PROCUREMENT ACTIVITIES OF ECONOMIC ENTITIES IN THE MARKET ECONOMY

    Directory of Open Access Journals (Sweden)

    E. A. Starozhuk

    2016-01-01

    Full Text Available The relevance of the topic chosen due to the current state of organization of purchasing activity of economic entities, which has undergone significant changes in the conditions of market economy. These changes consist in the fact that instead of the stock distribution of goods under the planned centralized system of economic management, the system of centralized customer attachment to the suppliers of solid state prices, the inequality of economic entities, tight regulation of supply of goods, came the era of free market relations.In the first part of the article provides an overview of contemporary works of authors and their views on the procurement activities of organizations and enterprises.The second part of the article describes the direction, the form of procurement enterprises, taking into account the peculiarities of their development and functioning.The first phase of the study was to identify the basic definitions of procurement enterprises in difficult socio-economic conditions. The second phase of the study was to determine the ranking of factors procurement activities.The purpose / goal. The aim of the article is to analyze the purchasing activities of the enterprises; study the best ways of functioning of the enterprises in order to achieve high economic efficiency through the development of the process of procurement.Methodology. The methodological basis of this article are the economic and statistical methods  of analysis, legal documents  in the area of procurement, public analyzes of the development of economic structures.Conclusions / relevance. The practical significance of the work lies in the provisions of the orientation, the findings and the rationale of the provisions of procurement that can be used by the legislative and executive authorities of the Russian Federation in the current activity.

  14. Allergic fungal rhino sinusitis with granulomas: A new entity?

    Science.gov (United States)

    Gupta, Rijuneeta; Gupta, Ashok K; Patro, Sourabha Kumar; Yadav, Jagveer; Chakrabarti, Arunaloke; Das, Ashim; Chatterjee, Debajyoti

    2015-08-01

    Allergic fungal rhino sinusitis (AFS) is classically described as allergic manifestation to the fungal antigen present in sinuses with no evidence of invasion. Granulomas in histopathology, suspicious of invasion, are occasionally observed in AFS and the disease in these patients behaves like invasive fungal sinusitis even without histologic evidence of invasion. We retrospectively studied AFS patients to analyze whether AFS should be continued to be designated as an allergic entity. AFS patients operated from January 2009 to July 2013 were retrospectively reviewed. Of the total 57 cases operated in last 4 years, nine showing presence of granuloma in histology were included in the AFS with granuloma Group (group 1) and the rest 48 were included in the AFS group (group 2). Both the groups were compared in terms of various parameters at presentation, treatment course and rate of recurrence. Group 1 had significantly high rates of orbital erosion (P = .000), with positive association of skull base erosion (P = .092) and high rates of telecanthus (P = .000), diplopia (P = .000), proptosis (P = .161) and facial pain. Recurrent surgery was needed in 8 of 9 patients in the group 1 as compared to 1 of 48 patients group 2. Granulomas suggests a more severe disease with a trend toward the invasive fungal sinusitis and alerts the clinician regarding the nature of progression. AFS seems to be a part of a continuous spectrum of fungal sinusitis rather than an allergic form as a distinct entity. © The Author 2015. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  15. Catatonia as a putative nosological entity: A historical sketch.

    Science.gov (United States)

    Gazdag, Gábor; Takács, Rozalia; Ungvari, Gabor S

    2017-09-22

    Kahlbaum was the first to propose catatonia as a separate disease following the example of general paresis of the insane, which served as a model for establishing a nosological entity. However, Kahlbaum was uncertain about the nosological position of catatonia and considered it a syndrome, or "a temporary stage or a part of a complex picture of various disease forms". Until recently, the issue of catatonia as a separate diagnostic category was not entertained, mainly due to a misinterpretation of Kraepelin's influential views on catatonia as a subtype of schizophrenia. Kraepelin concluded that patients presenting with persistent catatonic symptoms, which he called "genuine catatonic morbid symptoms", particularly including negativism, bizarre mannerisms, and stereotypes, had a poor prognosis similar to those of paranoid and hebephrenic presentations. Accordingly, catatonia was classified as a subtype of dementia praecox/schizophrenia. Despite Kraepelin's influence on psychiatric nosology throughout the 20(th) century, there have only been isolated attempts to describe and classify catatonia outside of the Kraepelinian system. For example, the Wernicke-Kleist-Leonhard school attempted to comprehensively elucidate the complexities of psychomotor disturbances associated with major psychoses. However, the Leonhardian categories have never been subjected to the scrutiny of modern investigations. The first three editions of the DSM included the narrow and simplified version of Kraepelin's catatonia concept. Recent developments in catatonia research are reflected in DSM-5, which includes three diagnostic categories: Catatonic Disorder due to Another Medical Condition, Catatonia Associated with another Mental Disorder (Catatonia Specifier), and Unspecified Catatonia. Additionally, the traditional category of catatonic schizophrenia has been deleted. The Unspecified Catatonia category could encourage research exploring catatonia as an independent diagnostic entity.

  16. Rare Earth Ion-Doped Upconversion Nanocrystals: Synthesis and Surface Modification

    Directory of Open Access Journals (Sweden)

    Hongjin Chang

    2014-12-01

    Full Text Available The unique luminescent properties exhibited by rare earth ion-doped upconversion nanocrystals (UCNPs, such as long lifetime, narrow emission line, high color purity, and high resistance to photobleaching, have made them widely used in many areas, including but not limited to high-resolution displays, new-generation information technology, optical communication, bioimaging, and therapy. However, the inherent upconversion luminescent properties of UCNPs are influenced by various parameters, including the size, shape, crystal structure, and chemical composition of the UCNPs, and even the chosen synthesis process and the surfactant molecules used. This review will provide a complete summary on the synthesis methods and the surface modification strategies of UCNPs reported so far. Firstly, we summarize the synthesis methodologies developed in the past decades, such as thermal decomposition, thermal coprecipitation, hydro/solvothermal, sol-gel, combustion, and microwave synthesis. In the second part, five main streams of surface modification strategies for converting hydrophobic UCNPs into hydrophilic ones are elaborated. Finally, we consider the likely directions of the future development and challenges of the synthesis and surface modification, such as the large-scale production and actual applications, stability, and so on, of the UCNPs.

  17. 77 FR 37806 - Disregarded Entities and the Indoor Tanning Services Excise Tax

    Science.gov (United States)

    2012-06-25

    ...This document contains final and temporary regulations relating to disregarded entities (including qualified subchapter S subsidiaries) and the indoor tanning services excise tax. These regulations affect disregarded entities responsible for collecting the indoor tanning services excise tax and owners of those disregarded entities. The text of these temporary regulations serves as the text of proposed regulations (REG-125570-11) published in the Proposed Rules section in this issue of the Federal Register.

  18. 77 FR 37838 - Disregarded Entities and the Indoor Tanning Services Excise Tax

    Science.gov (United States)

    2012-06-25

    ...In the Rules and Regulations section of this issue of the Federal Register, the IRS is issuing temporary regulations relating to disregarded entities (including qualified subchapter S subsidiaries) and the indoor tanning services excise tax. These regulations affect disregarded entities responsible for collecting the indoor tanning services excise tax and owners of those disregarded entities. The text of the temporary regulations also serves as the text of the proposed regulations.

  19. Effective development of the entities on the basis of forecasting of financial and economic activities

    Directory of Open Access Journals (Sweden)

    I. I. Shanin

    2017-01-01

    Full Text Available In article, the questions connected with approach on effective development of industrial enterprises on the example of the furniture entities are considered. Effective development of the entities is directed to cost reduction in case of production and implementation of products, for improvement of indicators of financial and economic activities. The research is conducted on the example of the furniture entities of the Voronezh region and Krasnodar Krai. Any entity constantly uses these or those resources connected with material, labor and finance costs. All resources, which are consumed during a certain production cycle, create a cost budget or the expense plan of the entity, which are the most important economic indicators of activities of any entity. Not always at the entities the attention is properly paid to forecasting of production expenses for a further stage of functioning. Most the entities will organize the activities in such a way that current plans pass from year to year, and at the same time the alternative ways directed to cost reduction in case of production and further sales of products aren't considered. Any entity needs forecasting and planning of costs for the following production stages, for the purposes of innovative development and effective functioning of productive activity of the entity. First, it is necessary for assessment of opportunities when financing productive activity and for further scheduling of expenses, directed to cost reduction and cost reallocation. Having analysed activities of the entities and having studied accounting (financial records, it is revealed that at the entities in 2015 in comparison with 2014, there was a decrease in outputs, but at the same time, the loss is observed. Based on the carried-out analysis, on the example of financial and economic activities of JSC GRAFSKOYE and JSC GKMF, conclusions are drawn, cost reduction allowances in case of production are revealed, and recommendations in

  20. The Transversal Organization of the Economic Entities of the Coal Mining Industry

    OpenAIRE

    Ileana Sorina (Rakos) Boca; Sorinel Capusneanu; Dana Maria Oprea; Anamaria Tepes Bobescu

    2013-01-01

    This article demonstrates the possibilities of transversal organization of mining economic entities in Romania. Objectives of economic entities are described and steps to take in order to realize transversal organizing according to the specific of Activity-Based Costing method. All methodology of transversal organization is adapted to the specific of Romanian mining economic entities. In the transversal organizational stages were considered the conclusions of the implementation team. The arti...

  1. Anatomical entity recognition with a hierarchical framework augmented by external resources.

    Directory of Open Access Journals (Sweden)

    Yan Xu

    Full Text Available References to anatomical entities in medical records consist not only of explicit references to anatomical locations, but also other diverse types of expressions, such as specific diseases, clinical tests, clinical treatments, which constitute implicit references to anatomical entities. In order to identify these implicit anatomical entities, we propose a hierarchical framework, in which two layers of named entity recognizers (NERs work in a cooperative manner. Each of the NERs is implemented using the Conditional Random Fields (CRF model, which use a range of external resources to generate features. We constructed a dictionary of anatomical entity expressions by exploiting four existing resources, i.e., UMLS, MeSH, RadLex and BodyPart3D, and supplemented information from two external knowledge bases, i.e., Wikipedia and WordNet, to improve inference of anatomical entities from implicit expressions. Experiments conducted on 300 discharge summaries showed a micro-averaged performance of 0.8509 Precision, 0.7796 Recall and 0.8137 F1 for explicit anatomical entity recognition, and 0.8695 Precision, 0.6893 Recall and 0.7690 F1 for implicit anatomical entity recognition. The use of the hierarchical framework, which combines the recognition of named entities of various types (diseases, clinical tests, treatments with information embedded in external knowledge bases, resulted in a 5.08% increment in F1. The resources constructed for this research will be made publicly available.

  2. Entity information life cycle for big data master data management and information integration

    CERN Document Server

    Talburt, John R

    2015-01-01

    Entity Information Life Cycle for Big Data walks you through the ins and outs of managing entity information so you can successfully achieve master data management (MDM) in the era of big data. This book explains big data's impact on MDM and the critical role of entity information management system (EIMS) in successful MDM. Expert authors Dr. John R. Talburt and Dr. Yinle Zhou provide a thorough background in the principles of managing the entity information life cycle and provide practical tips and techniques for implementing an EIMS, strategies for exploiting distributed processing to hand

  3. Facile synthesis of 5 nm NaYF₄:Yb/Er nanoparticles for targeted upconversion imaging of cancer cells.

    Science.gov (United States)

    Hu, Yueli; Wu, Boyue; Jin, Qing; Wang, Xueyuan; Li, Yan; Sun, Yuxiu; Huo, Jianzhong; Zhao, Xiaojun

    2016-05-15

    5nm intense green emission NaYF4:Yb/Er upconversion nanoparticles (UCNPs) with pure β phase was synthesized with a simple "green" strategy for the first time. Traditional organic solvothermal method is often applied to prepare the high-quality and uniform UCNPs, but the preparation of lanthanide-oleate complexes is laborious as heating and multistep post-treatment for purification are often required. The water-alcohols solvothermal method is environmentally friendly, but the fabricated UCNPs have big size, poor biocompatibility and high cytotoxicity, which limited their application for cell imaging. Herein, NaYF4:Yb/Er UCNPs were prepared with rare-earth nitrates RE(NO3)3 (RE=Y0.80 Yb0.18 Er0.02) as precursors and diethylene glycol (DEG)/ethylene glycol (EG)/water as the solvent. A facile green solvothermal method with the temperature being controlled at 300°C was developed. The as-prepared NaYF4:Yb/Er UCNPs were characterized and were found to have enhanced UC emission and controllable particle size. The as-prepared UCNPs were further functionalized via folic acid coating for the targeted imaging and improved bio- compatibility. It was made the UCNPs potential for upconversion bioimaging of living cells by the strong upconversion luminescence, the excellent biocompatibility, and the super-small size. The good colloidal stability and low cell cytotoxicity of the as-prepared UCNPs and the developed synthesis protocol might advance both the fields of UCNPs and biomolecule-based nanotechnology for future studies. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. DOING BUSINESS IN ROMANIA - PART I: PERSPECTIVES ON THE TYPES OF DOING BUSINESS. TYPES OF INDIVIDUAL AND COMPANY ENTITIES WITHOUT LEGAL PERSONALITY. TYPES OF ENTITIES WITH LEGAL PERSONALITY

    Directory of Open Access Journals (Sweden)

    Rodica Diana APAN

    2014-12-01

    Full Text Available The analysis in the present study integrates the types of trading entities in order to clearly determine them. A first reference theme when setting-up a business is that of the legal personality it would take. The new Civil Code, acting as common law in the field of trading entities, determines the realignment and balancing of the regulations on types of business. Company Law 31 of 1990 preserves the types of trading entities with legal personality regulated here: general partnership, limited partnership, limited partnership by shares, limited liability company, joint-stock company. The simple partnership which can gain legal personality is widely regulated, and for the partnership are mainly preserved the landmarks drawn by the Commercial Code of 1886 that is presently repealed. In conclusion, the present study analyses and answers the question – who are the legal trading entities and what are the regulated types of business.

  5. Various criteria in the evaluation of biomedical named entity recognition

    Directory of Open Access Journals (Sweden)

    Lin Yu-Chun

    2006-02-01

    Full Text Available Abstract Background Text mining in the biomedical domain is receiving increasing attention. A key component of this process is named entity recognition (NER. Generally speaking, two annotated corpora, GENIA and GENETAG, are most frequently used for training and testing biomedical named entity recognition (Bio-NER systems. JNLPBA and BioCreAtIvE are two major Bio-NER tasks using these corpora. Both tasks take different approaches to corpus annotation and use different matching criteria to evaluate system performance. This paper details these differences and describes alternative criteria. We then examine the impact of different criteria and annotation schemes on system performance by retesting systems participated in the above two tasks. Results To analyze the difference between JNLPBA's and BioCreAtIvE's evaluation, we conduct Experiment 1 to evaluate the top four JNLPBA systems using BioCreAtIvE's classification scheme. We then compare them with the top four BioCreAtIvE systems. Among them, three systems participated in both tasks, and each has an F-score lower on JNLPBA than on BioCreAtIvE. In Experiment 2, we apply hypothesis testing and correlation coefficient to find alternatives to BioCreAtIvE's evaluation scheme. It shows that right-match and left-match criteria have no significant difference with BioCreAtIvE. In Experiment 3, we propose a customized relaxed-match criterion that uses right match and merges JNLPBA's five NE classes into two, which achieves an F-score of 81.5%. In Experiment 4, we evaluate a range of five matching criteria from loose to strict on the top JNLPBA system and examine the percentage of false negatives. Our experiment gives the relative change in precision, recall and F-score as matching criteria are relaxed. Conclusion In many applications, biomedical NEs could have several acceptable tags, which might just differ in their left or right boundaries. However, most corpora annotate only one of them. In our

  6. Aqueous hydrodechlorination of 4-chlorophenol over an Rh/reduced graphene oxide synthesized by a facile one-pot solvothermal process under mild conditions

    Energy Technology Data Exchange (ETDEWEB)

    Ren, Yanlin [Chemical Synthesis and Pollution Control, Key Laboratory of Sichuan Province, College of Chemistry and Chemical Industry, China West Normal University, Nanchong 637002 (China); Fan, Guangyin, E-mail: fanguangyin@cwnu.edu.cn [Chemical Synthesis and Pollution Control, Key Laboratory of Sichuan Province, College of Chemistry and Chemical Industry, China West Normal University, Nanchong 637002 (China); Wang, Chenyu [Department of Chemistry, State University of New York at Binghamton, Binghamton, NY 13902 (United States)

    2014-06-01

    Graphical abstract: The Rh nanoparticles/reduced graphene oxide (Rh NPs/RGO) nanocatalyst synthesized by a solvothermal technique showed high activity and stability for the hydrodechlorination of 4-chlorophenol under mild conditions. - Highlights: • Rh/RGO was synthesized through a one-pot polyol reduction of GO and RhCl{sub 3}. • Complete HDC of 4-chlorophenol was obtained in aqueous phase without any additive. • The Rh/RGO exhibited an excellent catalytic performance for HDC reaction. - Abstract: Reduced graphene oxide (RGO) supported rhodium nanoparticles (Rh-NPs/RGO) was synthesized through one-pot polyol co-reduction of graphene oxide (GO) and rhodium chloride. The catalytic property of Rh-NPs/RGO was investigated for the aqueous phase hydrodechlorination (HDC) of 4-chlorophenol (4-CP). A complete conversion of 4-CP into high valued products of cyclohexanone (selectivity: 23.2%) and cyclohexanol (selectivity: 76.8%) was successfully achieved at 303 K and balloon hydrogen pressure in a short reaction time of 50 min when 1.5 g/L of 4-CP was introduced. By comparing with Rh-NPs deposited on the other supports, Rh-NPs/RGO delivered the highest initial rate (111.4 mmol/g{sub Rh} min) for 4-CP HDC reaction under the identical conditions. The substantial catalytic activity of Rh-NPs/RGO can be ascribed to the small and uniform particle size of Rh (average particle size was 1.7 ± 0.14 nm) on the surface of the RGO sheets and an electron-deficient state of Rh in the catalyst as a result of the strong interaction between the active sites and the surface function groups of RGO.

  7. Spectroscopic and magnetic properties of neodymium doped in GdPO{sub 4} sub-micron-stars prepared by solvothermal method

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, G.A., E-mail: ajith@gakumar.net [Department of Physics and Astronomy, University of Texas at San Antonio, San Antonio, TX, 78249 (United States); Balli, Nicolas R. [Department of Physics and Astronomy, University of Texas at San Antonio, San Antonio, TX, 78249 (United States); Kailasnath, M. [International School of Photonics, Cochin University of Science and Technology, Kochi, 682022 (India); Mimun, L. Christopher [Department of Physics and Astronomy, University of Texas at San Antonio, San Antonio, TX, 78249 (United States); Dannangoda, Chamath; Martirosyan, Karen S. [University of Texas at Rio Grande Valley, Brownsville, TX, 78520 (United States); Santhosh, C. [Department of Atomic and Molecular Spectroscopy, Manipal University, Manipal, 576104 (India); Sardar, Dhiraj K. [Department of Physics and Astronomy, University of Texas at San Antonio, San Antonio, TX, 78249 (United States)

    2016-07-05

    Neodymium-doped gadolinium orthophosphate (GdPO{sub 4}:Nd{sup 3+}) luminomagnetic sub-micron-stars were prepared by solvothermal method using metal nitrates and phosphoric acid. Monoclinic star shaped in six lobed sub-micron-stars with 600 nm length is obtained with uniform particle size distribution. After heat-treatment at 800 °C for 1 h in air, the stars separate into isolated petal shaped particles and show characteristic emission bands of Nd{sup 3+} with the strongest emission at 1064 nm. The emission intensities and fluorescence decay times are dependent on the Nd{sup 3+} concentration with the highest emission intensity and longest fluorescence decay time of 311 μs at 1064 nm with 0.5 mol% Nd{sup 3+}. Under 808 nm excitation with 12 W/cm{sup 2} power density a quantum yield of 9% was obtained for the 1.0 mol% Nd{sup 3+}. The presence of paramagnetic Gd{sup 3+} gives magnetic properties to the phosphor with a calculated magnetic moment of 1510 and 107,965 Bohr magneton at 300 and 5 K, respectively. - Highlights: • Star shaped Nd doped GdPO{sub 4} sub-micron phosphor particles are prepared for the first time. • Particles show both optical and magnetic properties. • Under 808 nm excitation near infrared emission was observed at 1064 nm with 9% quantum yield. • Magnetic moment of the particle was 1510 and 107,965 Bohr magneton at 300 and 5 K, respectively.

  8. One-step solvothermal tailoring the compositions and phases of nickel cobalt sulfides on conducting oxide substrates as counter electrodes for efficient dye-sensitized solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Niu; Li, Guowang [College of Materials and Chemical Engineering, Hubei Provincial Collaborative Innovation Center for New Energy Microgrid, Collaborative Innovation Center for Energy Equipment of Three Gorges Region, China Three Gorges University, Yichang 443002 (China); Huang, Hua [Three Gorges Center for Product Quality Control, Yichang 443002 (China); Sun, Panpan; Xiong, Tianli; Xia, Zhifen; Zheng, Fang; Xu, Jixing [College of Materials and Chemical Engineering, Hubei Provincial Collaborative Innovation Center for New Energy Microgrid, Collaborative Innovation Center for Energy Equipment of Three Gorges Region, China Three Gorges University, Yichang 443002 (China); Sun, Xiaohua, E-mail: mksxh@163.com [College of Materials and Chemical Engineering, Hubei Provincial Collaborative Innovation Center for New Energy Microgrid, Collaborative Innovation Center for Energy Equipment of Three Gorges Region, China Three Gorges University, Yichang 443002 (China)

    2016-12-30

    Highlights: • Co-Ni-S nanoparticles were in-suit grown on FTO via a facile method. • By varying thiourea amount, several Co-Ni-S alloys were obtained. • Amongst the Co-Ni-S alloys, NiCo{sub 2}S{sub 4} exhibited the best electrocatalytic property. - Abstract: Several nickel cobalt sulfide (Ni-Co-S) counter electrodes (CEs) are prepared, and the Ni-Co-S nanoparticles are in-situ grown on SnO{sub 2}: F (FTO) transparent conductive glasses via a facile solvothermal process, in which thiourea is used as the sulfurizing reagent. The X-ray diffraction, scanning electron microscopy, and energy dispersive spectrometer are employed to measure the microstructure and composition of the Ni-Co-S CEs. When a proper amount of thiourea is adopted, fine crystalline NiCo{sub 2}S{sub 4} CE is obtained. When the amount of thiourea is small or large, (Ni,Co){sub 4}S{sub 3} or (Ni,Co){sub 3}S{sub 4} CE is acquired, respectively. Cyclic voltammetry, electrochemical impedance spectroscopy, Tafel polarization and open-circuit voltage decay (OCVD) measurements all demonstrate that the electrocatalytic activities and electrical conductivities of these Ni-Co-S CEs all approach or exceed those of Pt-pyrolysis CE. Their superior electrochemical performances are further confirmed by fabricating DSSCs with the Ni-Co-S CEs, they display similar or better photo-electric conversion efficiencies to/than the Pt-pyrolysis counterpart.

  9. Solvothermally-Prepared Cu2 O Electrocatalysts for CO2 Reduction with Tunable Selectivity by the Introduction of p-Block Elements.

    Science.gov (United States)

    Larrazábal, Gastón O; Martín, Antonio J; Krumeich, Frank; Hauert, Roland; Pérez-Ramírez, Javier

    2017-03-22

    The electroreduction of CO2 to fuels and chemicals is an attractive strategy for the valorization of CO2 emissions. In this study, a Cu2 O electrocatalyst prepared by a simple and potentially scalable solvothermal route effectively targeted CO evolution at low-to-moderate overpotentials [with a current efficiency for CO (CECO ) of ca. 60 % after 12 h at -0.6 V vs. reversible hydrogen electrode, RHE], and its selectivity was tuned by the introduction of p-block elements (In, Sn, Ga, Al) into the catalyst. SEM, HRTEM, and voltammetric analyses revealed that the Cu2 O catalyst undergoes extensive surface restructuring (favorable for CO evolution) under the reaction conditions. The modification of Cu2 O with Sn and In further enhanced the current efficiency (CE) for CO (ca. 75 % after 12 h at -0.6 V). In contrast, the introduction of Al altered the selectivity profile of the catalyst significantly, decreasing the selectivity toward CO but promoting the reduction of CO2 to ethylene (CE≈7 %), n-propanol, and ethanol (CE≈2 % each) at -0.8 V vs. RHE. This result is related to a decreased reducibility of Al-doped Cu2 O that might preserve Cu+ species (favorable for C2 H4 production) under the reaction conditions, which is supported by XRD, X-ray photoelectron spectroscopy, and H2 temperature-programmed reduction observations. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Visible light photocatalysts (Fe, N):TiO{sub 2} from ammonothermally processed, solvothermal self-assembly derived Fe-TiO{sub 2} mesoporous microspheres

    Energy Technology Data Exchange (ETDEWEB)

    Zou, Mingming; Xiong, Fengqiang; Ganeshraja, Ayyakannu Sundaram [Dalian Institute of Chemical Physics (DICP), Chinese Academy of Sciences, 457 Zhongshan Road, Dalian, Liaoning, 116023 (China); Feng, Xiaohua; Wang, Chuanxi [Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, 315201 (China); Thomas, Tiju, E-mail: tijuthomas@iitm.ac.in [Department of Metallurgical and Materials Engineering, Indian Institute of Technology Madras, Chennai, 600036, Tamil Nadu (India); Yang, Minghui, E-mail: myang@dicp.ac.cn [Dalian Institute of Chemical Physics (DICP), Chinese Academy of Sciences, 457 Zhongshan Road, Dalian, Liaoning, 116023 (China)

    2017-07-01

    Iron (III) and nitrogen co-doped mesoporous TiO{sub 2} microspheres (Fe-N-TiO{sub 2}) are prepared using a self-assembly based solvothermal process followed by an ammonothermal method. Among all samples, 1 mol.% of Fe dopants and 500 °C nitridation (for 2 h) gives the highest visible light photoactivity. Results imply that the Fe{sup 3+}/Fe{sup 2+} dopant trap energy level introduced within the band gap in mildly Fe (∼1 at%) doped TiO{sub 2} and the mesoporous nature of the material, both aid in the observed catalytic performance. Subjecting Fe-TiO{sub 2} samples to ammonothermal process induces oxygen vancancies, and substitutional and interstitial N. This reduces optical band gap, and introduces local states. The lower band gap and local states together aid in the absorption of visible light and separation of charge carriers. Co-dopants are distributed uniformly in the best photocatalysts. The active species generated in the photocatalytic system is shown to be singlet molecular oxygen ({sup 1}O{sub 2}) using selective radical quenchers. - Highlights: • Iron (III) and nitrogen co-doped mesoporous TiO{sub 2} microspheres (Fe-N-TiO{sub 2}) are prepared. • Fe{sup 3+}/Fe{sup 2+} dopant trap energy level introduced within the band gap in Fe (∼1 at%) doped TiO{sub 2}. • Subjecting Fe-TiO{sub 2} samples to ammonothermal process induces oxygen vancancies, and causes substitutional and interstitial N. • Co-dopants are distributed uniformly in the best photocatalysts. • Active species generated is shown to be singlet molecular oxygen ({sup 1}O{sub 2}).

  11. 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.

  12. Eosinophilic esophagitis: A relevant entity for the otolaryngologist.

    Science.gov (United States)

    Górriz-Gil, Carmen; Villarreal, Ithzel M; Álvarez-Montero, Óscar; Rodríguez-Valiente, Antonio; Magaz, Marta; García-Berrocal, José R

    2016-01-01

    Eosinophilic esophagitis (EE) is a recently recognised pathologic entity whose prevalence has risen significantly since it was first described. Its diagnosis represents a challenge for different medical specialties, among which ENT specialists play an important role. Clinical suspicion in a patient with recurrent food impaction or a child with eating disorders and history of hypersensitivity constitutes the first warning sign of a possible EE. The purpose of this review is to highlight EE as a possible differential diagnosis in patients with deglutition disorders and describe the possible clinical symptoms that should alert the ENT specialist to perform appropriate diagnostic tests and procedures. The transnasal esophagoscopy, performed in-office by the ENT, is ideal for reducing possible underdiagnosed cases. Given the fact that an ENT specialist will evaluate a great many patients with deglutition disorders, it is paramount for possible EE cases to be suspected and recognised so that a correct multidisciplinary approach involving not only ENT specialists but also paediatricians, gastroenterologists, allergologists and pathologists can be established. Identifying the dietary component responsible for the esophageal inflammation and removing that food from the patient's diet is the key in the treatment of this immune-mediated disease. Copyright © 2015 Elsevier España, S.L.U. y Sociedad Española de Otorrinolaringología y Cirugía de Cabeza y Cuello. All rights reserved.

  13. Zoonoses As Ecological Entities: A Case Review of Plague.

    Science.gov (United States)

    Zeppelini, Caio Graco; de Almeida, Alzira Maria Paiva; Cordeiro-Estrela, Pedro

    2016-10-01

    As a zoonosis, Plague is also an ecological entity, a complex system of ecological interactions between the pathogen, the hosts, and the spatiotemporal variations of its ecosystems. Five reservoir system models have been proposed: (i) assemblages of small mammals with different levels of susceptibility and roles in the maintenance and amplification of the cycle; (ii) species-specific chronic infection models; (ii) flea vectors as the true reservoirs; (iii) Telluric Plague, and (iv) a metapopulation arrangement for species with a discrete spatial organization, following a source-sink dynamic of extinction and recolonization with naïve potential hosts. The diversity of the community that harbors the reservoir system affects the transmission cycle by predation, competition, and dilution effect. Plague has notable environmental constraints, depending on altitude (500+ meters), warm and dry climates, and conditions for high productivity events for expansion of the transmission cycle. Human impacts are altering Plague dynamics by altering landscape and the faunal composition of the foci and adjacent areas, usually increasing the presence and number of human cases and outbreaks. Climatic change is also affecting the range of its occurrence. In the current transitional state of zoonosis as a whole, Plague is at risk of becoming a public health problem in poor countries where ecosystem erosion, anthropic invasion of new areas, and climate change increase the contact of the population with reservoir systems, giving new urgency for ecologic research that further details its maintenance in the wild, the spillover events, and how it links to human cases.

  14. Zoonoses As Ecological Entities: A Case Review of Plague.

    Directory of Open Access Journals (Sweden)

    Caio Graco Zeppelini

    2016-10-01

    Full Text Available As a zoonosis, Plague is also an ecological entity, a complex system of ecological interactions between the pathogen, the hosts, and the spatiotemporal variations of its ecosystems. Five reservoir system models have been proposed: (i assemblages of small mammals with different levels of susceptibility and roles in the maintenance and amplification of the cycle; (ii species-specific chronic infection models; (ii flea vectors as the true reservoirs; (iii Telluric Plague, and (iv a metapopulation arrangement for species with a discrete spatial organization, following a source-sink dynamic of extinction and recolonization with naïve potential hosts. The diversity of the community that harbors the reservoir system affects the transmission cycle by predation, competition, and dilution effect. Plague has notable environmental constraints, depending on altitude (500+ meters, warm and dry climates, and conditions for high productivity events for expansion of the transmission cycle. Human impacts are altering Plague dynamics by altering landscape and the faunal composition of the foci and adjacent areas, usually increasing the presence and number of human cases and outbreaks. Climatic change is also affecting the range of its occurrence. In the current transitional state of zoonosis as a whole, Plague is at risk of becoming a public health problem in poor countries where ecosystem erosion, anthropic invasion of new areas, and climate change increase the contact of the population with reservoir systems, giving new urgency for ecologic research that further details its maintenance in the wild, the spillover events, and how it links to human cases.

  15. C1q Nephropathy: The Unique Underrecognized Pathological Entity

    Directory of Open Access Journals (Sweden)

    Joe Devasahayam

    2015-01-01

    Full Text Available C1q nephropathy is a rare glomerular disease with characteristic mesangial C1q deposition noted on immunofluorescence microscopy. It is histologically defined and poorly understood. Light microscopic features are heterogeneous and comprise minimal change disease (MCD, focal segmental glomerulosclerosis (FSGS, and proliferative glomerulonephritis. Clinical presentation is also diverse, and ranges from asymptomatic hematuria or proteinuria to frank nephritic or nephrotic syndrome in both children and adults. Hypertension and renal insufficiency at the time of diagnosis are common findings. Optimal treatment is not clear and is usually guided by the underlying light microscopic lesion. Corticosteroids are the mainstay of treatment, with immunosuppressive agents reserved for steroid resistant cases. The presence of nephrotic syndrome and FSGS appear to predict adverse outcomes as opposed to favorable outcomes in those with MCD. Further research is needed to establish C1q nephropathy as a universally recognized distinct clinical entity. In this paper, we discuss the current understanding of pathogenesis, histopathology, clinical features, therapeutic options, and outcomes of C1q nephropathy.

  16. Headache associated with airplane travel: a rare entity.

    Science.gov (United States)

    Cherian, Ajith; Mathew, Mini; Iype, Thomas; Sandeep, P; Jabeen, Afshan; Ayyappan, K

    2013-01-01

    Airplane travel headache is rare and has recently been described as a new form of headache associated with a specific situation. Of the 1,208 patients with primary headaches attending a tertiary care neurology hospital, two (0.16%) patients satisfied the criteria for headache related to airplane travel. Both the patients fulfilled the proposed diagnostic criteria for airplane travel headache. This unique headache had a mean duration of 24 minutes, localized to the medial supraorbital region described as having an intense jabbing or stabbing character that occurred exclusively and maximally during aircraft landing or take-off, following which pain intensity subsided . This rare headache felt on aircraft descent is probably due to the squeeze effect on the frontal sinus wall, when air trapped inside it contracts producing a negative pressure leading to mucosal edema, transudation and intense pain. Use of nasal decongestants either alone or in combination with naproxen sodium prior to ascent and descent abated the headache episodes. Awareness about this unique entity is essential to provide proper treatment and avoid patient suffering.

  17. Mapping biological entities using the longest approximately common prefix method.

    Science.gov (United States)

    Rudniy, Alex; Song, Min; Geller, James

    2014-06-14

    The significant growth in the volume of electronic biomedical data in recent decades has pointed to the need for approximate string matching algorithms that can expedite tasks such as named entity recognition, duplicate detection, terminology integration, and spelling correction. The task of source integration in the Unified Medical Language System (UMLS) requires considerable expert effort despite the presence of various computational tools. This problem warrants the search for a new method for approximate string matching and its UMLS-based evaluation. This paper introduces the Longest Approximately Common Prefix (LACP) method as an algorithm for approximate string matching that runs in linear time. We compare the LACP method for performance, precision and speed to nine other well-known string matching algorithms. As test data, we use two multiple-source samples from the Unified Medical Language System (UMLS) and two SNOMED Clinical Terms-based samples. In addition, we present a spell checker based on the LACP method. The Longest Approximately Common Prefix method completes its string similarity evaluations in less time than all nine string similarity methods used for comparison. The Longest Approximately Common Prefix outperforms these nine approximate string matching methods in its Maximum F1 measure when evaluated on three out of the four datasets, and in its average precision on two of the four datasets.

  18. Subacute Sclerosing Panencephalitis of the Brainstem as a Clinical Entity.

    Science.gov (United States)

    Upadhyayula, Pavan S; Yang, Jason; Yue, John K; Ciacci, Joseph D

    2017-11-07

    Subacute sclerosing panencephalitis (SSPE) is a rare progressive neurological disorder of early adolescence caused by persistent infection of the measles virus, which remains prevalent worldwide despite an effective vaccine. SSPE is a devastating disease with a characteristic clinical course in subcortical white matter; however, atypical presentations of brainstem involvement may be seen in rare cases. This review summarizes reports to date on brainstem involvement in SSPE, including the clinical course of disease, neuroimaging presentations, and guidelines for treatment. A comprehensive literature search was performed for English-language publications with keywords "subacute sclerosing panencephalitis" and "brainstem" using the National Library of Medicine PubMed database (March 1981-September 2017). Eleven articles focusing on SSPE of the brainstem were included. Predominant brainstem involvement remains uncharacteristic of SSPE, which may lead to misdiagnosis and poor outcome. A number of case reports have demonstrated brainstem involvement associated with other intracranial lesions commonly presenting in later SSPE stages (III and IV). However, brainstem lesions can appear in all stages, independent of higher cortical structures. The varied clinical presentations complicate diagnosis from a neuroimaging perspective. SSPE of the brainstem is a rare but important clinical entity. It may present like canonical SSPE or with unique clinical features such as absence seizures and pronounced ataxia. While SSPE generally progresses to the brainstem, it can also begin with a primary focus of infection in the brainstem. Awareness of varied SSPE presentations can aid in early diagnosis as well as guide management and treatment.

  19. Subacute Sclerosing Panencephalitis of the Brainstem as a Clinical Entity

    Directory of Open Access Journals (Sweden)

    Pavan S. Upadhyayula

    2017-11-01

    Full Text Available Subacute sclerosing panencephalitis (SSPE is a rare progressive neurological disorder of early adolescence caused by persistent infection of the measles virus, which remains prevalent worldwide despite an effective vaccine. SSPE is a devastating disease with a characteristic clinical course in subcortical white matter; however, atypical presentations of brainstem involvement may be seen in rare cases. This review summarizes reports to date on brainstem involvement in SSPE, including the clinical course of disease, neuroimaging presentations, and guidelines for treatment. A comprehensive literature search was performed for English-language publications with keywords “subacute sclerosing panencephalitis” and “brainstem” using the National Library of Medicine PubMed database (March 1981–September 2017. Eleven articles focusing on SSPE of the brainstem were included. Predominant brainstem involvement remains uncharacteristic of SSPE, which may lead to misdiagnosis and poor outcome. A number of case reports have demonstrated brainstem involvement associated with other intracranial lesions commonly presenting in later SSPE stages (III and IV. However, brainstem lesions can appear in all stages, independent of higher cortical structures. The varied clinical presentations complicate diagnosis from a neuroimaging perspective. SSPE of the brainstem is a rare but important clinical entity. It may present like canonical SSPE or with unique clinical features such as absence seizures and pronounced ataxia. While SSPE generally progresses to the brainstem, it can also begin with a primary focus of infection in the brainstem. Awareness of varied SSPE presentations can aid in early diagnosis as well as guide management and treatment.

  20. Short Segment Hiatal Hernia: Is It a Clinically Significant Entity?

    Science.gov (United States)

    Hyun, Jong Jin; Kim, Ji Hoon; Yeon, Jong Eun; Park, Jong-Jae; Kim, Jae Seon; Byun, Kwan Soo

    2010-01-01

    Introduction Hiatal hernia (HH) is a well-known contributory factor of gastroesophageal reflux disease (GERD). However, studies on the clinical significance of simple small HH are lacking. We conducted a study to clarify the clinical significance of short segment HH (SSHH) in relation to GERD. Methods 4,592 consecutive cases (male/female: 2,076/2,516, median age: 49 years) examined with diagnostic esophagogastroduodenoscopy for the first time were enrolled. During the insertion of endoscope, presence of HH was determined and the length was measured, if present. The relationships between gender, age, presence of erosive esophagitis, and columnar-lined esophagus (CLE) and the lengths of HH were analyzed. Results Among 4,592 cases, HH was present in 428 cases (9.3%); SSHH was found in 255 cases (5.6%) and long segment HH (LSHH) in 173 cases (3.8%). HH was more frequent among males and patients with LSHH tended to be older. Erosive esophagitis was observed in 4.8%, 22.0%, and 37.0% of no HH, SSHH, and LSHH group, respectively (p <0.05). CLE was observed in 14.4%, 36.5%, and 24.3% of no HH, SSHH, and LSHH group, respectively (p <0.05). Conclusions SSHH is not a clinically silent and "innocent entity," but rather a condition with a significant pathologic significance similar to LSHH in regard to GERD. PMID:20535324