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Sample records for temperature synthetic route

  1. Solid-state thermal decomposition of the [Co(NH3)5CO3]NO3·0.5H2O complex: A simple, rapid and low-temperature synthetic route to Co3O4 nanoparticles

    International Nuclear Information System (INIS)

    Farhadi, Saeid; Safabakhsh, Jalil

    2012-01-01

    Highlights: ► [Co(NH 3 ) 5 CO 3 ]NO 3 ·0.5H 2 O complex was used for preparing pure Co 3 O 4 nanoparticles. ► Co 3 O 4 nanoparticles were prepared at low temperature of 175 °C. ► Co 3 O 4 nanoparticles show a weak ferromagnetic behaviour at room temperature. ► The method is simple, low-cost and suitable for the production of Co 3 O 4 . - Abstract: Co 3 O 4 nanoparticles were easily prepared via the decomposition of the pentammine(carbonato)cobalt(III) nitrate precursor complex [Co(NH 3 ) 5 CO 3 ]NO 3 ·0.5H 2 O at low temperature (175 °C). The product was characterized by thermal analysis, X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), UV–visible spectroscopy, transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDX), Raman spectroscopy, Brunauer–Emmett–Teller (BET) specific surface area measurements and magnetic measurements. The FT-IR, XRD, Raman and EDX results indicated that the synthesized Co 3 O 4 nanoparticles are highly pure and have a single phase. The TEM analysis revealed nearly uniform and quasi-spherical Co 3 O 4 nanoparticles with an average particle size of approximately 10 nm. The optical absorption spectrum of the Co 3 O 4 nanoparticles showed two direct band gaps of 2.18 and 3.52 eV with a red shift in comparison with previous reported values. The prepared Co 3 O 4 nanoparticles showed a weak ferromagnetic behaviour that could be attributed to uncompensated surface spins and/or finite-size effects. Using the present method, Co 3 O 4 nanoparticles can be produced without expensive organic solvents and complicated equipment. This simple, rapid, safe and low-cost synthetic route can be extended to the synthesis of other transition-metal oxides.

  2. Low-Temperature Synthesis Routes to Intermetallic Superconductors

    Energy Technology Data Exchange (ETDEWEB)

    Schaak, Raymond E

    2008-01-08

    Over the past few years, our group has gained expertise at developing low-temperature solution-based synthetic pathways to complex nanoscale solids, with particular emphasis on nanocrystalline intermetallic compounds. Our synthetic capabilities are providing tools to reproducibly generate intermetallic nanostructures with simultaneous control over crystal structure, composition, and morphology. This DOE-funded project aims to expand these capabilities to intermetallic superconductors. This could represent an important addition to the tools that are available for the synthesis and processing of intermetallic superconductors, which traditionally utilize high-temperature, high-pressure, thin film, or gas-phase vacuum deposition methods. Our current knowledge of intermetallic superconductors suggests that significant enhancements could result from the inherent benefits of low-temperature solution synthesis, e.g. metastable phase formation, control over nanoscale morphology to facilitate size-dependent property studies, robust and inexpensive processability, low-temperature annealing and consolidation, and impurity incorporation (for doping, stoichiometry control, flux pinning, and improving the critical fields). Our focus is on understanding the superconducting properties as a function of synthetic route, crystal structure, crystallite size, and morphology, and developing the synthetic tools necessary to accomplish this. This research program can currently be divided into two classes of superconducting materials: intermetallics (transition metal/post transition metal) and metal carbides/borides. Both involve the development and exploitation of low-temperature synthesis routes followed by detailed characterization of structures and properties, with the goal of understanding how the synthetic pathways influence key superconducting properties of selected target materials. Because of the low-temperature methods used to synthesize them and the nanocrystalline morphologies

  3. Green synthetic route for perfumery compound (2-methoxyethyl ...

    Indian Academy of Sciences (India)

    POOJA R TAMBE

    2017-11-16

    Nov 16, 2017 ... oil is a clear light yellow liquid highly soluble in water. ... fore, inventing a green catalytic route for the synthesis of PEME is desirable ... But there are no reports on the synthesis of PEME using. DMC as ... The reactor was heated to attain a tempera- .... of gases (CO2 and N2) during the combustion pro- cess.

  4. Synthetic routes to some isotopically labelled intermediates for diterpenoid biosynthesis

    International Nuclear Information System (INIS)

    Dawson, R.M.; Godfrey, I.M.; Hogg, R.W.; Knox, J.R.

    1989-01-01

    The exo-15-hydrogen of ent-kaurene can be exchanged through a reversible ene reaction in a convenient and efficient procedure which has the potential for giving high specific activity 3 H-labelling. Copalol, the (Z)-double bond stereoisomer, and the allylic alcohol isomers ent-manool and ent-epimanool have been obtained through divergent synthetic pathways involving a 15,16-bisnor ketone intermediate. These pathways have also allowed the four compounds to be obtained with 14 C-labelling. A method, involving a Wittig reaction to form a vinyl bromide intermediate, has been developed for obtaining copalol, as the trityl ether derivative, with stereospecific isotopic labelling of one or the other of the hydrogens of the exocyclic methylene group. 27 refs., figs

  5. Synthetic biology routes to bio-artificial intelligence

    Science.gov (United States)

    Zaikin, Alexey; Saka, Yasushi; Romano, M. Carmen; Giuraniuc, Claudiu V.; Kanakov, Oleg; Laptyeva, Tetyana

    2016-01-01

    The design of synthetic gene networks (SGNs) has advanced to the extent that novel genetic circuits are now being tested for their ability to recapitulate archetypal learning behaviours first defined in the fields of machine and animal learning. Here, we discuss the biological implementation of a perceptron algorithm for linear classification of input data. An expansion of this biological design that encompasses cellular ‘teachers’ and ‘students’ is also examined. We also discuss implementation of Pavlovian associative learning using SGNs and present an example of such a scheme and in silico simulation of its performance. In addition to designed SGNs, we also consider the option to establish conditions in which a population of SGNs can evolve diversity in order to better contend with complex input data. Finally, we compare recent ethical concerns in the field of artificial intelligence (AI) and the future challenges raised by bio-artificial intelligence (BI). PMID:27903825

  6. An overview of the synthetic routes to the best selling drugs containing 6-membered heterocycles

    Directory of Open Access Journals (Sweden)

    Marcus Baumann

    2013-10-01

    Full Text Available This review which is the second in this series summarises the most common synthetic routes as applied to the preparation of many modern pharmaceutical compounds categorised as containing a six-membered heterocyclic ring. The reported examples are based on the top retailing drug molecules combining synthetic information from both scientific journals and the wider patent literature. It is hoped that this compilation, in combination with the previously published review on five-membered rings, will form a comprehensive foundation and reference source for individuals interested in medicinal, synthetic and preparative chemistry.

  7. A Simple, General Synthetic Route toward Nanoscale Transition Metal Borides.

    Science.gov (United States)

    Jothi, Palani R; Yubuta, Kunio; Fokwa, Boniface P T

    2018-04-01

    Most nanomaterials, such as transition metal carbides, phosphides, nitrides, chalcogenides, etc., have been extensively studied for their various properties in recent years. The similarly attractive transition metal borides, on the contrary, have seen little interest from the materials science community, mainly because nanomaterials are notoriously difficult to synthesize. Herein, a simple, general synthetic method toward crystalline transition metal boride nanomaterials is proposed. This new method takes advantage of the redox chemistry of Sn/SnCl 2 , the volatility and recrystallization of SnCl 2 at the synthesis conditions, as well as the immiscibility of tin with boron, to produce crystalline phases of 3d, 4d, and 5d transition metal nanoborides with different morphologies (nanorods, nanosheets, nanoprisms, nanoplates, nanoparticles, etc.). Importantly, this method allows flexibility in the choice of the transition metal, as well as the ability to target several compositions within the same binary phase diagram (e.g., Mo 2 B, α-MoB, MoB 2 , Mo 2 B 4 ). The simplicity and wide applicability of the method should enable the fulfillment of the great potential of this understudied class of materials, which show a variety of excellent chemical, electrochemical, and physical properties at the microscale. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Synthetic biology routes to bio-artificial intelligence.

    Science.gov (United States)

    Nesbeth, Darren N; Zaikin, Alexey; Saka, Yasushi; Romano, M Carmen; Giuraniuc, Claudiu V; Kanakov, Oleg; Laptyeva, Tetyana

    2016-11-30

    The design of synthetic gene networks (SGNs) has advanced to the extent that novel genetic circuits are now being tested for their ability to recapitulate archetypal learning behaviours first defined in the fields of machine and animal learning. Here, we discuss the biological implementation of a perceptron algorithm for linear classification of input data. An expansion of this biological design that encompasses cellular 'teachers' and 'students' is also examined. We also discuss implementation of Pavlovian associative learning using SGNs and present an example of such a scheme and in silico simulation of its performance. In addition to designed SGNs, we also consider the option to establish conditions in which a population of SGNs can evolve diversity in order to better contend with complex input data. Finally, we compare recent ethical concerns in the field of artificial intelligence (AI) and the future challenges raised by bio-artificial intelligence (BI). © 2016 The Author(s). This is an open access article published by Portland Press Limited on behalf of the Biochemical Society and distributed under the Creative Commons Attribution License 4.0 (CC BY).

  9. Novel metal oxides prepared by ingenious synthetic routes

    International Nuclear Information System (INIS)

    Rao, C.N.R.; Gopalakrishnan, J.; Vidyasagar, K.; Ganguli, A.K.; Ramanan, A.; Ganapathi, L.

    1986-01-01

    Several novel oxides have been prepared by the decomposition of carbonate precursors of calcite structure of the general formulas Mn/sub 1-x/M/sub x/CO 3 (M = Mg,Co,Cd), Ca/sub 1-x/M/sup prime//sub x/CO 3 , and Ca/sub 1-x/-yM/sup //sub x/M/sup double-prime//sub y/CO 3 (M',M'' = Mn,Fe,Co). Typical of the oxides synthesized are a variety of monoxides, Mn/sub 1-x/M/sub x/O, of rocksalt structure and perovskite-related oxides such as Ca 2 FeCoO 5 , Ca 2 Co 2 O 5 , and Ca 3 Fe 2 MnO 8 , many of them exhibiting novel anion-vacancy-ordered superstructures. An interesting series of oxides prepared by the topotactic reduction of Ca 2 Fe/sub 2-x/Mn/sub x/O/sub 6-y/ (synthesized by the decomposition of the corresponding carbonate precursors) is Ca 2 Fe/sub 2-x/Mn/sub x/O 5 where three different coordination polyhedra (octahedra, tetrahedra, and square pyramids) of the transition metals coexist. Topotactic reduction of LaCoO 3 and LaNiO 3 yields new oxides, La 2 Co 2 O 5 and La 2 Ni 2 O 5 , possessing anion-vacancy-ordered superstructures. While La 2 Co 2 O 5 adopts the brownmillerite structure, La 2 Ni 2 O 5 exhibits a new type of vacancy ordering with octahedral and square-planar coordination of Ni 2+ . Slightly reduced LaNiO 3 seem to exhibit crystallographic shear (CS) planes similar to WO/sub 3-x/. Topotactic dehydration of isostructural Mo/sub 1-x/W/sub x/O 3 x H 2 O provides a convenient route for the synthesis of Mo/sub 1-x/W/sub x/O 3 (0 3 -related structure

  10. Electron Beam Mediated Simple Synthetic Route to Preparing Layered Zinc Hydroxide

    International Nuclear Information System (INIS)

    Bae, Hyo Sun; Jung, Hyun

    2012-01-01

    We have developed a novel and eco-friendly synthetic route for the preparation of a two-dimensional layered zinc hydroxide with intercalated nitrate anions. The layered zinc hydroxide nitrate, called 'zinc basic salt', was, in general, successfully synthesized, using an electron beam irradiation technique. The 2-propanol solutions containing hydrated zinc nitrate were directly irradiated with an electron-beam at room temperature, under atmospheric conditions, without stabilizers or base molecules. Under electron beam irradiation, the reactive OH· radicals were generated by radiolysis of water molecules in precursor metal salts. After further radiolytic processes, the hydroxyl anions might be formed by the reaction of solvated electrons and the OH· radical. Finally, the Zn 5 (OH) 8 (NO 3 ) 2 ·2H 2 O was precipitated by the reaction of zinc cation and hydroxyl anions. Structure and morphology of obtained compounds were characterized by powder X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), and high resolution transmission electron microscopy (HR-TEM). The chemical components of the products were determined by Fourier transform infrared spectroscopy (FT-IR) and elemental analysis (EA). The thermal behavior of products was studied by thermogravimetric (TG) and differential thermal analysis (DTA)

  11. Development of new synthetic routes to bile pigments and synthesis of deuterated porphyrins

    International Nuclear Information System (INIS)

    Shim, Y.K.

    1985-01-01

    New synthetic routes to pyrromethanones using hydrogen peroxide/pyridine upon alpha-free pyrromethanes and a synthesis of mesobiliverdin are described. The pyrromethanones were applied to the synthesis of mesobiliverdin using 2,3-dichloro-5,6-dicyanobenzoquinone (DDQ) oxidation of mesourbilin, to give a high yield of the desired mesobiliverdin. New synthetic methodology to pyrrolinones using various oxidizing reagents were also described. Treatment of alpha-free pyrrole with thallium(III) trifluoroacetate (TTFA) gave a mixture of a pyrrolinone and a dimeric compound. The yield and the ratio of the two products were variable depending upon the solvents and the mole ratio of the TTFA used. Pyrrolinone syntheses using the other oxidizing reagents are also described. Syntheses of carbon-14 labelled biliverdins are also described. In addition, the preparation of biliverdin IX-BETA using b-bilene route is described. The second part of this study contains an introduction to porphyrins and syntheses of 6,7-bis(2-methoxycarbonyl-1,1-dideuteroethyl)-1,3,5,8-tetramethyl-2,4-divinylporphyrin. The latter is important in the study of heme protein reconstitution experiments. As a result of numerous synthetic approaches the desired product was obtained from the appropriately deuterated formylpyrrole using the a,c-biladiene route

  12. Synthetic wastewaters treatment by electrocoagulation to remove silver nanoparticles produced by different routes.

    Science.gov (United States)

    Matias, M S; Melegari, S P; Vicentini, D S; Matias, W G; Ricordel, C; Hauchard, D

    2015-08-15

    Nanoscience is a field that has stood out in recent years. The accurate long-term health and environmental risks associated with these emerging materials are unknown. Therefore, this work investigated how to eliminate silver nanoparticles (AgNPs) from synthetic effluents by electrocoagulation (EC) due to the widespread use of this type of nanoparticle (NP) in industry and its potential inhibition power over microorganisms responsible for biological treatment in effluent treatment plants. Synthesized AgNPs were studied via four different routes by chemical reduction in aqueous solutions to simulate the chemical variations of a hypothetical industrial effluent, and efficiency conditions of the EC treatment were determined. All routes used silver nitrate as the source of silver ions, and two synthesis routes were studied with sodium citrate as a stabilizer. In route I, sodium citrate functioned simultaneously as the reducing agent and stabilizing agent, whereas route II used sodium borohydride as a reducing agent. Route III used D-glucose as the reducing agent and sodium pyrophosphate as the stabilizer; route IV used sodium pyrophosphate as the stabilizing agent and sodium borohydride as the reducing agent. The efficiency of the EC process of the different synthesized solutions was studied. For route I, after 85 min of treatment, a significant decrease in the plasmon resonance peak of the sample was observed, which reflects the efficiency in the mass reduction of AgNPs in the solution by 98.6%. In route II, after 12 min of EC, the absorbance results reached the detection limit of the measurement instrument, which indicates a minimum reduction of 99.9% of AgNPs in the solution. During the 4 min of treatment in route III, the absorbance intensities again reached the detection limit, which indicates a minimum reduction of 99.8%. In route IV, after 10 min of treatment, a minimum AgNP reduction of 99.9% was observed. Based on these results, it was possible to verify that

  13. N-acylsulfonamides: Synthetic routes and biological potential in medicinal chemistry.

    Science.gov (United States)

    Ammazzalorso, Alessandra; De Filippis, Barbara; Giampietro, Letizia; Amoroso, Rosa

    2017-12-01

    Sulfonamide is a common structural motif in naturally occurring and synthetic medicinal compounds. The rising interest in sulfonamides and N-acyl derivatives is attested by the large number of drugs and lead compounds identified in last years, explored in different fields of medicinal chemistry and showing biological activity. Many acylsulfonamide derivatives were designed and synthesized as isosteres of carboxylic acids, being the characteristics of these functional groups very close. Starting from chemical routes to N-acylsulfonamides, this review explores compounds of pharmaceutical interest, developed as enzymatic inhibitors or targeting receptors. © 2017 John Wiley & Sons A/S.

  14. Route Generation for a Synthetic Character (BOT) Using a Partial or Incomplete Knowledge Route Generation Algorithm in UT2004 Virtual Environment

    Science.gov (United States)

    Hanold, Gregg T.; Hanold, David T.

    2010-01-01

    This paper presents a new Route Generation Algorithm that accurately and realistically represents human route planning and navigation for Military Operations in Urban Terrain (MOUT). The accuracy of this algorithm in representing human behavior is measured using the Unreal Tournament(Trademark) 2004 (UT2004) Game Engine to provide the simulation environment in which the differences between the routes taken by the human player and those of a Synthetic Agent (BOT) executing the A-star algorithm and the new Route Generation Algorithm can be compared. The new Route Generation Algorithm computes the BOT route based on partial or incomplete knowledge received from the UT2004 game engine during game play. To allow BOT navigation to occur continuously throughout the game play with incomplete knowledge of the terrain, a spatial network model of the UT2004 MOUT terrain is captured and stored in an Oracle 11 9 Spatial Data Object (SOO). The SOO allows a partial data query to be executed to generate continuous route updates based on the terrain knowledge, and stored dynamic BOT, Player and environmental parameters returned by the query. The partial data query permits the dynamic adjustment of the planned routes by the Route Generation Algorithm based on the current state of the environment during a simulation. The dynamic nature of this algorithm more accurately allows the BOT to mimic the routes taken by the human executing under the same conditions thereby improving the realism of the BOT in a MOUT simulation environment.

  15. A Low Temperature Synthetic Route to Nanocrystalline TiN

    African Journals Online (AJOL)

    NICO

    This method may be extended to the synthesis of other metal nitrides. ... direct current magnetron sputtering17, and mechanical mill- ... recent years, autoclaved synthesis of TiN nanomaterials from ... 3.2 XPS Characterization of the Samples.

  16. Cerium oxide for the destruction of chemical warfare agents: A comparison of synthetic routes

    Energy Technology Data Exchange (ETDEWEB)

    Janoš, Pavel, E-mail: pavel.janos@ujep.cz [Faculty of the Environment, University of Jan Evangelista Purkyně, Králova Výšina 7, 400 96 Ústí nad Labem (Czech Republic); Henych, Jiří [Faculty of the Environment, University of Jan Evangelista Purkyně, Králova Výšina 7, 400 96 Ústí nad Labem (Czech Republic); Institute of Inorganic Chemistry AS CR v.v.i., 25068 Řež (Czech Republic); Pelant, Ondřej; Pilařová, Věra; Vrtoch, Luboš [Faculty of the Environment, University of Jan Evangelista Purkyně, Králova Výšina 7, 400 96 Ústí nad Labem (Czech Republic); Kormunda, Martin [Faculty of Sciences, University of Jan Evangelista Purkyně, České Mládeže 8, 400 96 Ústí nad Labem (Czech Republic); Mazanec, Karel [Military Research Institute, Veslařská 230, 637 00 Brno (Czech Republic); and others

    2016-03-05

    Highlights: • Four synthetic routes were compared to prepare the nanoceria-based reactive sorbents. • The sorbents prepared by homogeneous hydrolysis destroy efficiently the soman and VX nerve agents. • Toxic organophosphates are converted to less-dangerous products completely within a few minutes. • Surface non-stoichiometry and −OH groups promote the destruction by the S{sub N}2 mechanism. - Abstract: Four different synthetic routes were used to prepare active forms of cerium oxide that are capable of destroying toxic organophosphates: a sol–gel process (via a citrate precursor), homogeneous hydrolysis and a precipitation/calcination procedure (via carbonate and oxalate precursors). The samples prepared via homogeneous hydrolysis with urea and the samples prepared via precipitation with ammonium bicarbonate (with subsequent calcination at 500 °C in both cases) exhibited the highest degradation efficiencies towards the extremely dangerous nerve agents soman (O-pinacolyl methylphosphonofluoridate) and VX (O-ethyl S-[2-(diisopropylamino)ethyl] methylphosphonothioate) and the organophosphate pesticide parathion methyl. These samples were able to destroy more than 90% of the toxic compounds in less than 10 min. The high degradation efficiency of cerium oxide is related to its complex surface chemistry (presence of surface −OH groups and surface non-stoichiometry) and to its nanocrystalline nature, which promotes the formation of crystal defects on which the decomposition of organophosphates proceeds through a nucleophilic substitution mechanism that is not dissimilar to the mechanism of enzymatic hydrolysis of organic phosphates by phosphotriesterase.

  17. Solid-state thermal decomposition of the [Co(NH{sub 3}){sub 5}CO{sub 3}]NO{sub 3}{center_dot}0.5H{sub 2}O complex: A simple, rapid and low-temperature synthetic route to Co{sub 3}O{sub 4} nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Farhadi, Saeid, E-mail: sfarhad2001@yahoo.com [Department of Chemistry, Lorestan University, Khorramabad 68135-465 (Iran, Islamic Republic of); Safabakhsh, Jalil [Department of Chemistry, Lorestan University, Khorramabad 68135-465 (Iran, Islamic Republic of)

    2012-02-25

    Highlights: Black-Right-Pointing-Pointer [Co(NH{sub 3}){sub 5}CO{sub 3}]NO{sub 3}{center_dot}0.5H{sub 2}O complex was used for preparing pure Co{sub 3}O{sub 4} nanoparticles. Black-Right-Pointing-Pointer Co{sub 3}O{sub 4} nanoparticles were prepared at low temperature of 175 Degree-Sign C. Black-Right-Pointing-Pointer Co{sub 3}O{sub 4} nanoparticles show a weak ferromagnetic behaviour at room temperature. Black-Right-Pointing-Pointer The method is simple, low-cost and suitable for the production of Co{sub 3}O{sub 4}. - Abstract: Co{sub 3}O{sub 4} nanoparticles were easily prepared via the decomposition of the pentammine(carbonato)cobalt(III) nitrate precursor complex [Co(NH{sub 3}){sub 5}CO{sub 3}]NO{sub 3}{center_dot}0.5H{sub 2}O at low temperature (175 Degree-Sign C). The product was characterized by thermal analysis, X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), UV-visible spectroscopy, transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDX), Raman spectroscopy, Brunauer-Emmett-Teller (BET) specific surface area measurements and magnetic measurements. The FT-IR, XRD, Raman and EDX results indicated that the synthesized Co{sub 3}O{sub 4} nanoparticles are highly pure and have a single phase. The TEM analysis revealed nearly uniform and quasi-spherical Co{sub 3}O{sub 4} nanoparticles with an average particle size of approximately 10 nm. The optical absorption spectrum of the Co{sub 3}O{sub 4} nanoparticles showed two direct band gaps of 2.18 and 3.52 eV with a red shift in comparison with previous reported values. The prepared Co{sub 3}O{sub 4} nanoparticles showed a weak ferromagnetic behaviour that could be attributed to uncompensated surface spins and/or finite-size effects. Using the present method, Co{sub 3}O{sub 4} nanoparticles can be produced without expensive organic solvents and complicated equipment. This simple, rapid, safe and low-cost synthetic route can be extended to the synthesis of other

  18. High temperature blankets for the production of synthetic fuels

    International Nuclear Information System (INIS)

    Powell, J.R.; Steinberg, M.; Fillo, J.; Makowitz, H.

    1977-01-01

    The application of very high temperature blankets to improved efficiency of electric power generation and production of H 2 and H 2 based synthetic fuels is described. The blanket modules have a low temperature (300 to 400 0 C) structure (SS, V, Al, etc.) which serves as the vacuum/coolant pressure boundary, and a hot (>1000 0 C) thermally insulated interior. Approximately 50 to 70% of the fusion energy is deposited in the hot interior because of deep penetration by high energy neutrons. Separate coolant circuits are used for the two temperature zones: water for the low temperature structure, and steam or He for the hot interior. Electric generation efficiencies of approximately 60% and H 2 production efficiencies of approximately 50 to 70%, depending on design, are projected for fusion reactors using these high temperature blankets

  19. TEMPERATURE-DEFORMATION CRITERION OF OPTIMIZATION OF FINE DRAWING HIGH CARBON WIRE ROUTE

    Directory of Open Access Journals (Sweden)

    Y. L. Bobarikin

    2012-01-01

    Full Text Available The temperature-deformation criterion of assessment and optimization of routes of the thin high-carbon wire drawing enabling to increase plastic properties of wire at retaining of its durability is offered.

  20. A Survey on Temperature-Aware Routing Protocols in Wireless Body Sensor Networks

    Directory of Open Access Journals (Sweden)

    Sangman Moh

    2013-08-01

    Full Text Available The rapid growth of the elderly population in the world and the rising cost of healthcare impose big issues for healthcare and medical monitoring. A Wireless Body Sensor Network (WBSN is comprised of small sensor nodes attached inside, on or around a human body, the main purpose of which is to monitor the functions and surroundings of the human body. However, the heat generated by the node’s circuitry and antenna could cause damage to the human tissue. Therefore, in designing a routing protocol for WBSNs, it is important to reduce the heat by incorporating temperature into the routing metric. The main contribution of this paper is to survey existing temperature-aware routing protocols that have been proposed for WBSNs. In this paper, we present a brief overview of WBSNs, review the existing routing protocols comparatively and discuss challenging open issues in the design of routing protocols.

  1. Synthetic Routes to N-9 Alkylated 8-Oxoguanines; Weak Inhibitors of the Human DNA Glycosylase OGG1

    Directory of Open Access Journals (Sweden)

    Tushar R. Mahajan

    2015-09-01

    Full Text Available The human 8-oxoguanine DNA glycosylase OGG1 is involved in base excision repair (BER, one of several DNA repair mechanisms that may counteract the effects of chemo- and radiation therapy for the treatment of cancer. We envisage that potent inhibitors of OGG1 may be found among the 9-alkyl-8-oxoguanines. Thus we explored synthetic routes to 8-oxoguanines and examined these as OGG1 inhibitors. The best reaction sequence started from 6-chloroguanine and involved N-9 alkylation, C-8 bromination, and finally simultaneous hydrolysis of both halides. Bromination before N-alkylation should only be considered when the N-substituent is not compatible with bromination conditions. The 8-oxoguanines were found to be weak inhibitors of OGG1. 6-Chloro-8-oxopurines, byproducts in the hydrolysis of 2,6-halopurines, turned out to be slightly better inhibitors than the corresponding 8-oxoguanines.

  2. Colloidal Magnetic Heterostructured Nanocrystals with Asymmetric Topologies: Seeded-Growth Synthetic Routes and Formation Mechanisms

    Science.gov (United States)

    Scarfiello, Riccardo; Nobile, Concetta; Cozzoli, P. Davide

    2016-12-01

    Colloidal inorganic nanocrystals, free-standing crystalline nanostructures generated and processed in solution phase, represent an important class of advanced nanoscale materials owing to the flexibility with which their physical-chemical properties can be controlled through synthetic tailoring of their compositional, structural and geometric features and the versatility with which they can be integrated in technological fields as diverse as optoelectronics, energy storage/ conversion/production, catalysis and biomedicine. In recent years, building upon mechanistic knowledge acquired on the thermodynamic and kinetic processes that underlie nanocrystal evolution in liquid media, synthetic nanochemistry research has made impressive advances, opening new possibilities for the design, creation and mastering of increasingly complex “colloidal molecules”, in which nanocrystal modules of different materials are clustered together via solid-state bonding interfaces into free-standing, easily processable multifunctional nanocomposite systems. This Review will provide a glimpse into this fast-growing research field by illustrating progress achieved in the wet-chemical development of last-generation breeds of all-inorganic heterostructured nanocrystals (HNCs) in asymmetric non-onionlike geometries, inorganic analogues of polyfunctional organic molecules, in which distinct nanoscale crystalline modules are interconnected in hetero-dimer, hetero-oligomer and anisotropic multidomain architectures via epitaxial heterointerfaces of limited extension. The focus will be on modular HNCs entailing at least one magnetic material component combined with semiconductors and/or metals, which hold potential for generating enhanced or unconventional magnetic properties, while offering diversified or even new chemical-physical properties and functional capabilities. The available toolkit of synthetic strategies, all based on the manipulation of seeded-growth techniques, will be described

  3. Colloidal Magnetic Heterostructured Nanocrystals with Asymmetric Topologies: Seeded-Growth Synthetic Routes and Formation Mechanisms

    Directory of Open Access Journals (Sweden)

    Riccardo Scarfiello

    2016-12-01

    Full Text Available Colloidal inorganic nanocrystals, free-standing crystalline nanostructures generated and processed in solution phase, represent an important class of advanced nanoscale materials owing to the flexibility with which their physical–chemical properties can be controlled through synthetic tailoring of their compositional, structural and geometric features and the versatility with which they can be integrated in technological fields as diverse as optoelectronics, energy storage/ conversion/production, catalysis and biomedicine. In recent years, building upon mechanistic knowledge acquired on the thermodynamic and kinetic processes that underlie nanocrystal evolution in liquid media, synthetic nanochemistry research has made impressive advances, opening new possibilities for the design, creation and mastering of increasingly complex colloidal molecules, in which nanocrystal modules of different materials are clustered together via solid-state bonding interfaces into free-standing, easily processable multifunctional nanocomposite systems. This Review will provide a glimpse into this fast-growing research field by illustrating progress achieved in the wet-chemical development of last-generation breeds of all-inorganic heterostructured nanocrystals (HNCs in asymmetric non-onionlike geometries, inorganic analogues of polyfunctional organic molecules, in which distinct nanoscale crystalline modules are interconnected in hetero-dimer, hetero-oligomer and anisotropic multidomain architectures via epitaxial heterointerfaces of limited extension. The focus will be on modular HNCs entailing at least one magnetic material component combined with semiconductors and/or metals, which hold potential for generating enhanced or unconventional magnetic properties, while offering diversified or even new chemical-physical properties and functional capabilities. The available toolkit of synthetic strategies, all based on the manipulation of seeded-growth techniques

  4. Silver Nanoparticles: Synthetic Routes, In Vitro Toxicity and Theranostic Applications for Cancer Disease

    Directory of Open Access Journals (Sweden)

    Valeria De Matteis

    2018-05-01

    Full Text Available The large use of nanomaterials in many fields of application and commercial products highlights their potential toxicity on living organisms and the environment, despite their physico-chemical properties. Among these, silver nanoparticles (Ag NPs are involved in biomedical applications such as antibacterial agents, drug delivery vectors and theranostics agents. In this review, we explain the common synthesis routes of Ag NPs using physical, chemical, and biological methods, following their toxicity mechanism in cells. In particular, we analyzed the physiological cellular pathway perturbations in terms of oxidative stress induction, mitochondrial membrane potential alteration, cell death, apoptosis, DNA damage and cytokines secretion after Ag NPs exposure. In addition, their potential anti-cancer activity and theranostic applications are discussed.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2014-11-15

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

  6. Sol–gel synthesis of vanadium doped titania: Effect of the synthetic routes and investigation of their photocatalytic properties in the presence of natural sunlight

    Energy Technology Data Exchange (ETDEWEB)

    Shao, Godlisten N., E-mail: shaogod@gmail.com [Department of Chemical Engineering, Hanyang University, 1271 Sa 3-dong, Sangnok-gu, Ansan-si, Gyeonggi-do 426-791 (Korea, Republic of); Department of Chemistry, Mkwawa College, University of Dar es Salaam, Iringa, United Republic of Tanzania (Tanzania, United Republic of); Imran, S.M.; Jeon, Sun Jeong; Kang, Shin Jae; Haider, S.M. [Department of Chemical Engineering, Hanyang University, 1271 Sa 3-dong, Sangnok-gu, Ansan-si, Gyeonggi-do 426-791 (Korea, Republic of); Kim, Hee Taik, E-mail: khtaik@yahoo.com [Department of Chemical Engineering, Hanyang University, 1271 Sa 3-dong, Sangnok-gu, Ansan-si, Gyeonggi-do 426-791 (Korea, Republic of)

    2015-10-01

    Highlights: • Sol–gel routes to yield vanadium doped titania from cheap source are proposed. • Photocatalysts with different titania polymorphs are yielded through calcination. • The vanadium doped titania samples show strong absorption in the visible region. • The activities of the photocatalysts are assessed in the presence of visible light. • The calcined samples are obtained through two-step process exhibit superior activities. - Abstract: The development of visible-light effective TiO{sub 2} photocatalysts allows low cost degradation of toxic non-biodegradable organic pollutants. In the present study a series of vanadium doped titania (V-TiO{sub 2}) photocatalysts with V-to-Ti of 0.03, 0.06 and 0.1 were synthesized by either one-step or two-step modified sol–gel approaches. Titanium oxychloride solution was used as a titania source while vanadium pentaoxide was used as a vanadia source to form V-TiO{sub 2} in the absence of surfactants. One-step process was performed through the reaction of the TiO{sub 2} source with vanadium source. In two-step route the Ti(OH){sub 4} gel was preformed through gelation of the TiO{sub 2} source using ammonium solution and then peptized in the acidic vanadium solution. The physicochemical properties of the samples were examined by XRF, XRD, UV–visible DRS, SEM-EDAX, TEM, DTA-TGA, XPS and nitrogen gas physisorption studies analyses. It was observed that the morphology, crystal structure and photochemical properties of the obtained samples were largely dependent on the calcination temperature, synthetic approach and V-to-Ti ratios. Calcination of the samples yielded large ultrafine and perhaps monodispersed particles with different sizes depending on the synthetic technique. The photocatalytic performance of the samples was tested in the photodegradation of methylene blue in the presence of natural sunlight. The photocatalytic activities of the samples synthesized by two-step route were higher than that of the

  7. Simple synthetic route to manganese-containing nanowires with the spinel crystal structure

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Lei; Zhang, Yan; Hudak, Bethany M.; Wallace, Damon K.; Kim, Doo Young; Guiton, Beth S.

    2016-08-15

    This report describes a new route to synthesize single-crystalline manganese-containing spinel nanowires (NWs) by a two-step hydrothermal and solid-state synthesis. Interestingly, a nanowire or nanorod morphology is maintained during conversion from MnO{sub 2}/MnOOH to CuMn{sub 2}O{sub 4}/Mg{sub 2}MnO{sub 4}, despite the massive structural rearrangement this must involve. Linear sweep voltammetry (LSV) curves of the products give preliminary demonstration that CuMn{sub 2}O{sub 4} NWs are catalytically active towards the oxygen evolution reaction (OER) in alkaline solution, exhibiting five times the magnitude of current density found with pure carbon black. - Highlights: • Synthesis of single-crystalline manganese-containing spinel nanowires. • Binary oxide nanowire converted to ternary oxide wire through solid state reaction. • Approach to structure conversion with shape retention could be generally applicable. • Copper and Manganese display multiple oxidation states with potential for catalysis. • CuMn{sub 2}O{sub 4} nanowires show promise as catalysts for the oxygen evolution reaction.

  8. Hydrogenation of carbon dioxide towards synthetic natural gas. A route to effective future energy storage

    Energy Technology Data Exchange (ETDEWEB)

    Schoder, M. [Hochschule Lausitz, Cottbus (Germany); Armbruster, U.; Martin, A. [Rostock Univ. (Germany). Leibniz Institute for Catalysis

    2012-07-01

    Ni- and Ru-based catalysts are best suited for the so-called Sabatier reaction, i.e., the hydrogenation of CO{sub 2} to synthetic natural gas (SNG). Besides using commercial materials, catalyst syntheses (5 wt% Ru or Ni) were carried out by incipient wetness impregnation of four carriers (TiO{sub 2}, SiO{sub 2}, ZrO{sub 2} and {gamma}-Al{sub 2}O{sub 3}). Some pre-tests revealed that catalysts supported on TiO{sub 2} and SiO{sub 2} mostly produced CO, and therefore, they were not studied in detail. The catalyst tests were carried out in a continuously operated tube reactor at 623-723 K and 1-20 bar. Ru/ZrO{sub 2} and Ni/{gamma}-Al{sub 2}O{sub 3} revealed best catalytic performance at ambient pressure. Methane selectivities of 99.9% at 81.2% CO{sub 2} conversion for Ru/ZrO{sub 2} (623 K) and of 98.9% at 73.8% CO{sub 2} conversion for Ni/{gamma}-Al{sub 2}O{sub 3} (673 K) were obtained. The conversion increased significantly with raising reaction pressure above 10 bar to reach more than 93% for the Ni-containing catalyst and more than 96% for the Zr catalysts. Methane as the target product was formed with a selectivity of 100%. In addition, the catalysts were characterized by various solid-state techniques such as BET, TPR, ICP-OES, XRD, XPS and TEM. (orig.)

  9. Poly (ether ether ketone) derivatives: Synthetic route and characterization of nitrated and sulfonated polymers

    International Nuclear Information System (INIS)

    Conceicao, T.F.; Bertolino, J.R.; Barra, G.M.O.; Pires, A.T.N.

    2009-01-01

    Nitrated and sulfonated poly (ether ether ketone) [SNPEEK] samples were prepared through sulfonation of nitrated PEEK (NPEEK) at different temperatures resulting in polymers with distinct sulfonation degrees (SD). The sulfonation occurred preferentially in the hydroquinone segment even after 81% of this moiety had been nitrated. Sulfonation in the benzophenone moiety was achieved only in 16% of this segment at the reaction temperature of 80 deg. C. The substitution degree was obtained through the TG curves, and values were in agreement with 1 H NMR data when SD is much higher as ND (nitration degree). The highest SD obtained was 72%. Membranes of the sulfonated and nitrated PEEK (SNPEEK) were prepared by casting and showed good ductility depending on the substitution degree, with proton conductivity in the order of 10 -2 S cm -1 , an important characteristic in some applications, such as in fuel cells

  10. Poly (ether ether ketone) derivatives: Synthetic route and characterization of nitrated and sulfonated polymers

    Energy Technology Data Exchange (ETDEWEB)

    Conceicao, T.F.; Bertolino, J.R. [Grupo de Estudo em Materiais Polimericos-Departamento de Quimica, Universidade Federal de Santa Catarina, Florianopolis, SC (Brazil); Barra, G.M.O. [Departamento de Engenharia Mecanica, Universidade Federal de Santa Catarina, Florianopolis, SC (Brazil); Pires, A.T.N. [Grupo de Estudo em Materiais Polimericos-Departamento de Quimica, Universidade Federal de Santa Catarina, Florianopolis, SC (Brazil)], E-mail: alfredotiburcio@pq.cnpq.br

    2009-03-01

    Nitrated and sulfonated poly (ether ether ketone) [SNPEEK] samples were prepared through sulfonation of nitrated PEEK (NPEEK) at different temperatures resulting in polymers with distinct sulfonation degrees (SD). The sulfonation occurred preferentially in the hydroquinone segment even after 81% of this moiety had been nitrated. Sulfonation in the benzophenone moiety was achieved only in 16% of this segment at the reaction temperature of 80 deg. C. The substitution degree was obtained through the TG curves, and values were in agreement with {sup 1}H NMR data when SD is much higher as ND (nitration degree). The highest SD obtained was 72%. Membranes of the sulfonated and nitrated PEEK (SNPEEK) were prepared by casting and showed good ductility depending on the substitution degree, with proton conductivity in the order of 10{sup -2} S cm{sup -1}, an important characteristic in some applications, such as in fuel cells.

  11. Role of synthetic route on the transport properties of BaCe1-xYxO3 proton conductor

    International Nuclear Information System (INIS)

    Chiodelli, Gaetano; Malavasi, Lorenzo; Tealdi, Cristina; Barison, Simona; Battagliarin, Marino; Doubova, Lioudmila; Fabrizio, Monica; Mortalo, Cecilia; Gerbasi, Rosalba

    2009-01-01

    In this paper the role of the preparation route on the transport properties of the BaCe 1-x Y x O 3-δ solid solution with x = 0, 0.1, 0.15, and 0.2 has been studied. In particular, the samples were synthesized by means of the solid-state reaction and by a modified Pechini method. The effect of grain size on the sintering behaviour of the two samples batches was investigated by means of impedance spectroscopy and electron microscopy. It was found that a good sintering of the pellets can be achieved at 1250 deg. C for the samples prepared through the Pechini method. The ceramic route, even at higher temperatures, does not lead to good density values. The extensive conductivity measurements as a function of doping and gas environment (pure oxygen and argon + 10% H 2 + water) we carried out showed that the optimal Y-doping is around 15% and that a significant proton conductivity can be achieved for T lower than 500 deg. C. Above this temperature, the role of oxygen defects starts becoming relevant. Finally, the presence of a slope change in all the Arrhenius plots, irrespective to the gas environment, at about 450-500 deg. C was observed and qualitatively interpreted as due to a change in the nature of the main charge carriers involved

  12. Oxide glass to high temperature ceramic superconductors - a novel route

    International Nuclear Information System (INIS)

    Chaudhuri, B.K.; Som, K.K.

    1992-01-01

    Recently it has been discovered that many of transition metal oxide (TMO) glasses like Bi-Sr-Ca-Cu-O, Y-Ba-Cu-O, Bi-Pb-Sr-Ca-Cu-O etc. can be directly converted to the corresponding high temperature superconducting phases by properly annealing the respective glasses. In this review recent developements in this field are summarised. The structural, electrical, dielectrical, magnetic, optical, and other properties of these new type of (TMO) glass systems have been elucidated comparing them with the corresponding results of already known (TMO) glasses which do not become superconductors on annealing above their glass transition temperatures (T g ). The electrical properties of this novel glass system have been analysed with reference to the various existing theoretical models based on polaron hopping conduction mechanism. The electrical, magnetic, and other properties of the respective superconductors obtained from their corresponding glass phases by annealing above (T g ) and the possibility of drawing wires, ribbons etc. from these glass matrices and then converting them to their high T c superconducting phases have also been discussed. (author). 107 refs., 32 figs., 5 tabs

  13. Phosphine synthetic route features and postsynthetic treatment of InP quantum dots

    International Nuclear Information System (INIS)

    Mordvinova, Natalia; Vinokurov, Alexander; Dorofeev, Sergey; Kuznetsova, Tatiana; Znamenkov, Konstantin

    2014-01-01

    Highlights: • Quantum dots with average diameter of 3–5 nm were synthesized. • PH 3 was used as novel phosphorous precursor. • Electrophoresis was demonstrated to be an effective method of purification of QDs. • Photoeching leads to quantum yields about 20%. • The concentration and time dependencies for photoetching of QDs were obtained. -- Abstract: In this paper we report on the development of synthesis of InP quantum dots with a gaseous phosphine PH 3 as a source of phosphorus and myristic acid and TOP/TOPO as stabilizers. Samples synthesized using myristic acid as stabilizer at relatively low temperatures were found to contain admixture of In(OH) 3 . We studied the influence of HF concentration and duration of illumination on luminescence properties of InP quantum dots during photoetching process. Quantum yields of photoetched samples reached about 20%. Additionally, electrophoresis as a new technique of purification and size-depended separation of synthesized quantum dots was developed

  14. Synthetic

    Directory of Open Access Journals (Sweden)

    Anna Maria Manferdini

    2010-06-01

    Full Text Available Traditionally materials have been associated with a series of physical properties that can be used as inputs to production and manufacturing. Recently we witnessed an interest in materials considered not only as ‘true matter’, but also as new breeds where geometry, texture, tooling and finish are able to provoke new sensations when they are applied to a substance. These artificial materials can be described as synthetic because they are the outcome of various qualities that are not necessarily true to the original matter, but they are the combination of two or more parts, whether by design or by natural processes. The aim of this paper is to investigate the potential of architectural surfaces to produce effects through the invention of new breeds of artificial matter, using micro-scale details derived from Nature as an inspiration.

  15. Thermal equation of state of synthetic orthoferrosilite at lunar pressures and temperatures

    NARCIS (Netherlands)

    de Vries, J.; Jacobs, J.M.G.; van den Berg, A.P.; Wehber, M.; Lathe, C.; McCammon, C.A.; van Westrenen, W.

    2013-01-01

    Iron-rich orthopyroxene plays an important role in models of the thermal and magmatic evolution of the Moon, but its density at high pressure and high temperature is not well-constrained. We present in situ measurements of the unit-cell volume of a synthetic polycrystalline end-member

  16. Nitrogen aggregation in Ib type synthetic diamonds at low pressure and high-temperature annealing

    International Nuclear Information System (INIS)

    Kazyuchits, N.M.; Rusetskij, M.S.; Latushko, Ya.I.; Kazyuchits, V.N.; Zajtsev, A.M.

    2015-01-01

    A new technique for annealing of diamonds at low pressure and high temperature (LPHT) is considered. The absorption spectra of synthetic Ib diamonds are given before and after annealing. This is evident from a comparison of the spectra that nitrogen aggregation process takes place at the LPHT annealing diamond. (authors)

  17. Synthetic cannabinoids found in "spice" products alter body temperature and cardiovascular parameters in conscious male rats.

    Science.gov (United States)

    Schindler, Charles W; Gramling, Benjamin R; Justinova, Zuzana; Thorndike, Eric B; Baumann, Michael H

    2017-10-01

    The misuse of synthetic cannabinoids is a persistent public health concern. Because these drugs target the same cannabinoid receptors as the active ingredient of marijuana, Δ 9 -tetrahydrocannabinol (THC), we compared the effects of synthetic cannabinoids and THC on body temperature and cardiovascular parameters. Biotelemetry transmitters for the measurement of body temperature or blood pressure (BP) were surgically implanted into separate groups of male rats. THC and the synthetic cannabinoids CP55,940, JWH-018, AM2201 and XLR-11 were injected s.c., and rats were placed into isolation cubicles for 3h. THC and synthetic cannabinoids produced dose-related decreases in body temperature that were most prominent in the final 2h of the session. The rank order of potency was CP55,940>AM2201=JWH-018>THC=XLR-11. The cannabinoid inverse agonist rimonabant antagonized the hypothermic effect of all compounds. Synthetic cannabinoids elevated BP in comparison to vehicle treatment during the first h of the session, while heart rate was unaffected. The rank order of potency for BP increases was similar to that seen for hypothermia. Hypertensive effects of CP55,940 and JWH-018 were not antagonized by rimonabant or the neutral antagonist AM4113. However, the BP responses to both drugs were antagonized by pretreatment with either the ganglionic blocker hexamethonium or the α 1 adrenergic antagonist prazosin. Our results show that synthetic cannabinoids produce hypothermia in rats by a mechanism involving cannabinoid receptors, while they increase BP by a mechanism independent of these sites. The hypertensive effect appears to involve central sympathetic outflow. Published by Elsevier B.V.

  18. Experiment Plan of High Temperature Steam and Carbon dioxide Co-electrolysis for Synthetic Gas Production

    International Nuclear Information System (INIS)

    Yoon, Duk-Joo; Ko, Jae-Hwa

    2008-01-01

    Currently, Solid oxide fuel cells (SOFC) come into the spotlight in the middle of the energy technologies of the future for highly effective conversion of fossil fuels into electricity without carbon dioxide emission. The SOFC is a reversible cell. By applying electrical power to the cell, which is solid oxide electrolysis cell (SOEC), it is possible to produce synthetic gas (syngas) from high temperature steam and carbon dioxide. The produced syngas (hydrogen and carbon monoxide) can be used for synthetic fuels. This SOEC technology can use high temperature from VHTRs for high efficiency. This paper describes KEPRI's experiment plan of high temperature steam and carbon co-electrolysis for syngas production using SOEC technology

  19. Preparation and Low Temperature Short-term Storage for Synthetic Seeds of Caladium bicolor

    Directory of Open Access Journals (Sweden)

    Mehpara MAQSOOD

    2015-03-01

    Full Text Available An efficient somatic embryo encapsulation and in vitro plant regeneration technique were established with Caladium bicolor, an important ornamental plant.Tuber derived embryogenic callus (95.50% was obtained on Murashige and Skoog (MS medium amended with 0.5 mg L-1 α-Naphthalene acetic acid (NAA + 0.5 mg L-1 6-Benzyladenine (BA. The embryogenic callus later differentiated into somatic embryos in the same plant growth regulators (PGRs added medium (NAA and BA. The induced embryos matured and developed into plantlets in NAA and BA added media; maximum plantlets development was observed at 1.0 mg L-1 NAA + 1.0 mg L-1 BA supplemented medium. Synthetic seeds were produced by encapsulating embryos in gel containing 3.0% sucrose + 3.0% sodium alginate and 100 mM of calcium chloride.The highest synthetic seed germination (97.6% was observed on medium supplemented with 1.0 mg L-1 NAA + 1.0 mg L-1 BA. The synthetic seeds were kept at low temperatures for storage; the encapsulated beads were viable and demonstrated good germination even after 12 weeks of storage at 4 °C. The plantlet recovery frequency was however declined with time. The synthetic seed derived plantlets were morphologically similar to the mother plant.

  20. Highly luminescent core-shell InP/ZnX (X = S, Se) quantum dots prepared via a phosphine synthetic route.

    Science.gov (United States)

    Mordvinova, Natalia; Vinokurov, Alexander; Kuznetsova, Tatiana; Lebedev, Oleg I; Dorofeev, Sergey

    2017-01-24

    Here we report a simple method for the creation of highly luminescent core-shell InP/ZnX (X = S, Se) quantum dots (QDs) on the basis of a phosphine synthetic route. In this method a Zn precursor was added to the reaction mixture at the beginning of the synthesis to form an In(Zn)P alloy structure, which promoted the formation of a ZnX shell. Core-shell InP/ZnX QDs exhibit highly intensive emission with a quantum yield over 50%. The proposed method is primarily important for practical applications. Advantages of this method compared to the widely used SILAR technique are discussed. We further demonstrate that the SILAR approach consisting of consequent addition of Zn and chalcogen precursors to pre-prepared non-doped InP colloidal nanoparticles is not quite suitable for shell growth without the addition of special activator agents or the use of very reactive precursors.

  1. Parallel- and serial-contact electrochemical metallization of monolayer nanopatterns: A versatile synthetic tool en route to bottom-up assembly of electric nanocircuits

    Directory of Open Access Journals (Sweden)

    Jonathan Berson

    2012-02-01

    Full Text Available Contact electrochemical transfer of silver from a metal-film stamp (parallel process or a metal-coated scanning probe (serial process is demonstrated to allow site-selective metallization of monolayer template patterns of any desired shape and size created by constructive nanolithography. The precise nanoscale control of metal delivery to predefined surface sites, achieved as a result of the selective affinity of the monolayer template for electrochemically generated metal ions, provides a versatile synthetic tool en route to the bottom-up assembly of electric nanocircuits. These findings offer direct experimental support to the view that, in electrochemical metal deposition, charge is carried across the electrode–solution interface by ion migration to the electrode rather than by electron transfer to hydrated ions in solution.

  2. Optimizing solid oxide fuel cell cathode processing route for intermediate temperature operation

    DEFF Research Database (Denmark)

    Ortiz-Vitoriano, N.; Bernuy-Lopez, Carlos; Ruiz de Larramendi, I.

    2013-01-01

    -priced raw material and cost-effective production techniques.In this work the perovskite-type La0.6Ca0.4Fe0.8Ni0.2O3 (LCFN) oxide has been used in order to optimize intermediate temperature SOFC cathode processing route. The advantages this material presents arise from the low temperature powder calcination......For Solid Oxide Fuel Cells (SOFCs) to become an economically attractive energy conversion technology suitable materials which allow operation at lower temperatures, while retaining cell performance, must be developed. At the same time, the cell components must be inexpensive - requiring both low...... (∼600°C) and electrode sintering (∼800°C) of LCFN electrodes, making them a cheaper alternative to conventional SOFC cathodes. An electrode polarization resistance as low as 0.10Ωcm2 at 800°C is reported, as determined by impedance spectroscopy studies of symmetrical cells sintered at a range...

  3. Ga(III) chelates of amphiphilic DOTA-based ligands: synthetic route and in vitro and in vivo studies

    International Nuclear Information System (INIS)

    Fontes, Andre; Prata, M. Isabel M.; Geraldes, Carlos F.G.C.; Andre, Joao P.

    2011-01-01

    In this work, we report on a synthetic strategy using amphiphilic DOTA (1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid)-based chelators bearing a variable-sized α-alkyl chain at one of the pendant acetate arms (from 6 to 14 carbon atoms), compatible with their covalent coupling to amine-bearing biomolecules. The amphiphilic behavior of the micelles-forming Ga(III) chelates (critical micellar concentration), their stability in blood serum and their lipophilicity (logP) were investigated. Biodistribution studies with the 67 Ga-labeled chelates were performed in Wistar rats, which showed a predominant liver uptake with almost no traces of the radiochelates in the body after 24 h.

  4. Ga(III) chelates of amphiphilic DOTA-based ligands: synthetic route and in vitro and in vivo studies

    Energy Technology Data Exchange (ETDEWEB)

    Fontes, Andre [Centro de Quimica, Campus de Gualtar, Universidade do Minho, 4710-057, Braga (Portugal); Prata, M. Isabel M. [IBILI, Faculdade de Medicina, Universidade de Coimbra, 3548, Coimbra (Portugal); Geraldes, Carlos F.G.C. [Departamento de Ciencias da Vida, Faculdade de Ciencias e Tecnologia, Universidade de Coimbra, 3001-401, Coimbra (Portugal); Centro de Neurociencias e Biologia Celular, Universidade de Coimbra, 3001-401, Coimbra (Portugal); Andre, Joao P., E-mail: jandre@quimica.uminho.p [Centro de Quimica, Campus de Gualtar, Universidade do Minho, 4710-057, Braga (Portugal)

    2011-04-15

    In this work, we report on a synthetic strategy using amphiphilic DOTA (1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid)-based chelators bearing a variable-sized {alpha}-alkyl chain at one of the pendant acetate arms (from 6 to 14 carbon atoms), compatible with their covalent coupling to amine-bearing biomolecules. The amphiphilic behavior of the micelles-forming Ga(III) chelates (critical micellar concentration), their stability in blood serum and their lipophilicity (logP) were investigated. Biodistribution studies with the {sup 67}Ga-labeled chelates were performed in Wistar rats, which showed a predominant liver uptake with almost no traces of the radiochelates in the body after 24 h.

  5. Influence of pre-measurement thermal treatment on OSL of synthetic quartz measured at room temperature

    International Nuclear Information System (INIS)

    Kale, Y.D.; Gandhi, Y.H.

    2008-01-01

    Much effort has been made to study the influence of pre-measurement thermal treatment and ionizing radiation on quartz specimens owing to its use in a large number of applications. Optically stimulated luminescence (OSL) being a structured and sensitive phenomenon promises to correlate the responsible color center and luminescence emission. OSL studies on quartz with such conditions can reveal many significant results. The aim of the present investigation is to understand the effect of annealing temperature on OSL characteristics of synthetic quartz recorded at room temperature. At identical annealing duration and β-dose, the shape of OSL decay curve remains non-exponential; when specimens annealed at lower temperature (∼400 deg. C). The shape of decay curve changes to exponential in nature along with rise in OSL intensity when the specimen was given higher temperature of annealing (>400 deg. C). The effects of such protocol on pattern of OSL sensitivity as well as area under the OSL decay curve are also presented here. The presence of shallow traps, when OSL decay curve was recorded at room temperature seems to be responsible for the changes in OSL pattern. The influence of shallow traps is attributed to non-exponential decay of OSL recorded at room temperature

  6. Chemical Routes to Colloidal Chalcogenide Nanosheets

    Energy Technology Data Exchange (ETDEWEB)

    Schaak, Raymond E. [Pennsylvania State Univ., University Park, PA (United States)

    2014-11-25

    This project began with an emphasis on developing new low-­temperature synthetic routes to intermetallic alloys in order to advance the synthesis and processing science of superconducting materials, as well as to potentially discover new materials that would be inaccessible using more traditional higher-­temperature methods. Our initial target materials, chosen as model systems for developing new low-­temperature solution-­based synthetic platforms, were based on well known superconducting alloys, including Nb3M (M = Ga, Ge, Sn), Bi-­M (M = In, Cu), and MgCNi3. Several key, fundamental synthetic challenges that underpinned the formation of these materials using solution chemistry routes were identified and investigated.

  7. A rapid room temperature chemical route for the synthesis of graphene: metal-mediated reduction of graphene oxide.

    Science.gov (United States)

    Dey, Ramendra Sundar; Hajra, Saumen; Sahu, Ranjan K; Raj, C Retna; Panigrahi, M K

    2012-02-07

    A rapid and facile route for the synthesis of reduced graphene oxide sheets (rGOs) at room temperature by the chemical reduction of graphene oxide using Zn/acid in aqueous solution is demonstrated. This journal is © The Royal Society of Chemistry 2012

  8. CuO nanostructures on copper foil by a simple wet chemical route at room temperature

    International Nuclear Information System (INIS)

    Jana, S.; Das, S.; Das, N.S.; Chattopadhyay, K.K.

    2010-01-01

    Uniform CuO nanostructures have been synthesized on copper foil substrates by oxidation of Cu in alkaline condition by a simple wet chemical route at room temperature. By controlling the alkaline condition (pH value) different CuO nanostructures like nanoneedles, self-assembled nanoflowers and staking of flake-like structures were achieved. The phase formation and the composition of the films were characterized by X-ray diffraction and energy dispersive analysis of X-ray studies. X-ray photoelectron spectroscopic studies indicated that the samples were composed of CuO. The morphologies of the films were investigated by scanning electron microscopy. A possible growth mechanism is also proposed here. Band gap energies of the nanostructures were determined from the optical reflectance spectra. The different CuO nanostructures showed good electron field emission properties with turn-on fields in the range 6-11.3 V μm -1 . The field emission current was significantly affected by the morphologies of the CuO films.

  9. Water solubility of synthetic pyrope at high temperature and pressure up to 12GPa

    Science.gov (United States)

    Huang, S.; Chen, J.

    2012-12-01

    Water can be incorporated into normally anhydrous minerals as OH- defects and transported into the mantle. Its existence in the mantle may affect property of minerals, such as elasticity, electrical conductivity and rheological properties. As the secondary mineral in the mantle, garnet has not been extensively studied for its water solubility and there is discrepancies among the existing experiments on the water solubility in the garnet change at pressures and temperatures. Geiger et al., 1991 investigated water content in synthetic pyrope and concluded 0.02wt% to 0.07wt% OH- substitution. Lu et al., 1997 found 198ppm water in the Dora Miara pyrope at 100Kbar and 1000°C. Withers et al., 1998 claimed that water solubility in pyrope reached 1000ppm at 5GPa and then decreased as pressure increasing; above 7GPa, no water was detected. Mookherjee et al., 2009 also explored pyrope-rich garnet, which contains water up to 0.1%wt at 5-9GPa and temperatures 1373K-1473K. Here we report a study of water solubility of synthetic single crystal pyrope at pressures 4-12GPa and temperature 1000°C. Single crystals of pyrope were synthesized using multi-anvil press and water contents in these samples were measured using FTIR. We have observed OH- peak at 3650 cm-1 along this pressure range, although Withers, 1998 reported water contents decrease to undetectable level above 7GPa. Water solubility in pyrope will be reported as a function of pressure up to 12 GPa at 1000°C.

  10. Near-infrared refractive index of synthetic single crystal and polycrystalline diamonds at high temperatures

    Science.gov (United States)

    Yurov, V. Yu.; Bushuev, E. V.; Popovich, A. F.; Bolshakov, A. P.; Ashkinazi, E. E.; Ralchenko, V. G.

    2017-12-01

    We measured the refractive index n(T) and thermo-optical coefficient β(T) = (1/n)(dn/dT) of high quality synthetic diamonds from room temperature to high temperatures, up to 1520 K, in near-infrared spectral range at wavelength 1.56 μm, using a low-coherence interferometry. A type IIa single crystal diamond produced by high pressure-high temperature technique and a transparent polycrystalline diamond grown by chemical vapor deposition were tested and revealed a very close n(T) behavior, with n = 2.384 ± 0.001 at T = 300 K, monotonically increasing to 2.428 at 1520 K. The n(T) data corrected to thermal expansion of diamond are well fitted with 3rd order polynomials, and alternatively, with the Bose-Einstein model with an effective oscillator frequency of 970 cm-1. Almost linear n(T) dependence is observed above 800 K. The thermo-optical coefficient is found to increase monotonically from (0.6 ± 0.1) × 10-5 K-1 (300 K) to (2.0 ± 0.1) × 10-5 K-1 (1300 K) with a tendency to saturation at >1200 K. These β(T) values are an order of magnitude lower than those known for Si, GaAs, and InP. The obtained results significantly extend the temperature range, where the refractive index of diamond was previously measured.

  11. Roles of adjuvant and route of vaccination in antibody response and protection engendered by a synthetic matrix protein 2-based influenza A virus vaccine in the mouse

    Directory of Open Access Journals (Sweden)

    Cudic Mare

    2007-10-01

    Full Text Available Abstract Background The M2 ectodomain (M2e of influenza A virus (IAV strains that have circulated in humans during the past 90 years shows remarkably little structural diversity. Since M2e-specific antibodies (Abs are capable of restricting IAV replication in vivo but are present only at minimal concentration in human sera, efforts are being made to develop a M2e-specific vaccine. We are exploring a synthetic multiple antigenic peptide (MAP vaccine and here report on the role of adjuvants (cholera toxin and immunostimulatory oligodeoxynucleotide and route of immunization on Ab response and strength of protection. Results Independent of adjuvants and immunization route, on average 87% of the M2e-MAP-induced Abs were specific for M2e peptide and a variable fraction of these M2e(pep-specific Abs (average 15% cross-reacted with presumably native M2e expressed by M2-transfected cells. The titer of these cross-reactive M2e(pep-nat-specific Abs in sera of parenterally immunized mice displayed a sigmoidal relation to level of protection, with EC50 of ~20 μg Ab/ml serum, though experiments with passive M2e(pep-nat Abs indicated that serum Abs did not fully account for protection in parenterally vaccinated mice, particularly in upper airways. Intranasal vaccination engendered stronger protection and a higher proportion of G2a Abs than parenteral vaccination, and the strength of protection failed to correlate with M2e(pep-nat-specific serum Ab titers, suggesting a role of airway-associated immunity in protection of intranasally vaccinated mice. Intranasal administration of M2e-MAP without adjuvant engendered no response but coadministration with infectious IAV slightly enhanced the M2e(pep-nat Ab response and protection compared to vaccination with IAV or adjuvanted M2e-MAP alone. Conclusion M2e-MAP is an effective immunogen as ~15% of the total M2e-MAP-induced Ab response is of desired specificity. While M2e(pep-nat-specific serum Abs have an important

  12. Stabilisation of phytosterols by natural and synthetic antioxidants in high temperature conditions.

    Science.gov (United States)

    Kmiecik, Dominik; Korczak, Józef; Rudzińska, Magdalena; Gramza-Michałowska, Anna; Hęś, Marzanna; Kobus-Cisowska, Joanna

    2015-04-15

    The aim of the study was to assess the potential applicability of natural antioxidants in the stabilisation of phytosterols. A mixture of β-sitosterol and campesterol was incorporated into triacylglycerols (TAGs). The following antioxidants were added to the prepared matrix: green tea extract, rosemary extract, a mix of tocopherols from rapeseed oil, a mix of synthetic tocopherols, phenolic compounds extracted from rapeseed meal, sinapic acid and butylated hydroxytoluene (BHT). Samples were heated at a temperature of 180 °C for 4 h. After the completion of heating, the losses of phytosterols were analysed, as well as the contents of β-sitosterol and campesterol oxidation products. The total content of phytosterol oxidation products in samples ranged from 96.69 to 268.35 μg/g of oil. The effectiveness of antioxidants decreased in the following order: phenolic compounds from rapeseed meal>rosemary extract>mix of tocopherols from rapeseed oil>mix of synthetic tocopherols>green tea extract>sinapic acid>BHT. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. Synthetic fuel production using Texas lignite and a very high temperature reactor for process heat

    International Nuclear Information System (INIS)

    Ross, M.A.; Klein, D.E.

    1982-01-01

    Two approaches for synthetic fuel production from coal are studied using Texas lignite as the feedstock. First, the gasification and liquefaction of coal are accomplished using Lurgi gasifiers and Fischer-Tropsch synthesis. A 50 000 barrel/day facility, consuming 13.7 million tonne/yr (15.1 million ton/yr) of lignite, is considered. Second, a nuclear-assisted coal conversion approach is studied using a very high temperature gas-cooled reactor with a modified Lurgi gasifier and Fischer-Tropsch synthesis. The nuclear-assisted approach resulted in a 35% reduction in coal consumption. In addition, process steam consumption was reduced by one-half and the oxygen plants were eliminated in the nuclear assisted process. Both approaches resulted in a synthetic oil price higher than the March 1980 imported price of $29.65 per barrel: $36.15 for the lignite-only process and $35.16 for the nuclear-assisted process. No tax advantage was assumed for either process and the utility financing method was used for both economic calculations

  14. Low-temperature structural phase transition in synthetic libethenite Cu2PO4OH

    International Nuclear Information System (INIS)

    Belik, Alexei A.; Naumov, Pance; Kim, Jungeun; Tsuda, Shunsuke

    2011-01-01

    Low-temperature structural properties of the synthetic mineral libethenite Cu 2 PO 4 OH were investigated by single-crystal X-ray diffraction, synchrotron X-ray powder diffraction, specific heat measurements, and Raman spectroscopy. A second-order structural phase transition from the Pnnm symmetry (a=8.0553(8) A, b=8.3750(9) A, c=5.8818(6) A at 180 K) to the P2 1 /n symmetry (a=8.0545(8) A, b=8.3622(9) A, c=5.8755(6) A, β=90.0012(15) at 120 K) was found at 160 K during cooling. At 120 K, the monoclinic angle is 90.0012(15) from single crystal X-ray data vs 90.083(1) from powder X-ray diffraction data. The P2 1 /n-to-Pnnm transition may be a general feature of the adamite-type compounds, M 2 XO 4 OH. - Graphical Abstract: Fragments of experimental synchrotron X-ray powder diffraction patterns of Cu 2 PO 4 OH between 100 and 280 K. Arrows show additional reflections that appear below 160 K in the monoclinic P2 1 /n phase. Highlights: → A low-temperature phase transition was found in the mineral libethenite Cu 2 PO 4 OH. → No magnetic anomalies and weak specific heat anomalies are detected. → Phase transition is of the second order. → Libethenite may exemplify a general feature of the adamite-type compounds.

  15. Highly regio- and diastereoselective, acidic clay supported intramolecular nitrile oxide-alkene cycloaddition on D-ribose derived nitriles: an efficient synthetic route to isoxazoline fused five and six membered carbocycles.

    Science.gov (United States)

    Panda, Amarendra; Das, Sulagna; Pal, Shantanu

    2014-10-29

    An efficient synthetic route to isoxazoline fused carbocycles from carbohydrate scaffolds that comprise of free hydroxyl group(s) is described with high regio- and stereoselectivity. Montmorillonite K-10/chloramine T oxidation and in situ intramolecular nitrile oxide-alkene cycloaddition (INOC) of D-ribose derived oximes have been developed for the diversity oriented synthesis of isoxazoline fused five and six membered carbocycles. Copyright © 2014 Elsevier Ltd. All rights reserved.

  16. Temperature dependence of morphology, structural and optical properties of ZnS nanostructures synthesized by wet chemical route

    International Nuclear Information System (INIS)

    Navaneethan, M.; Archana, J.; Nisha, K.D.; Hayakawa, Y.; Ponnusamy, S.; Muthamizhchelvan, C.

    2010-01-01

    Research highlights: → ZnS nanoparticles and nanorods have been synthesized by wet chemical route. → Higher annealing temperature influenced the change in morphology due to aggregation of the nanoparticles. → The temperature dependent optical properties were investigated. → Absorption edge of nanoparticles (295 nm) and nanorods (326 nm) were shifted towards shorter wavelength compared to bulk ZnS (337 nm) due to the quantum confinement effect. → ZnS nanoparticles exhibit high photoluminescence intensity than that of ZnS nanorods annealed at 180 o C. - Abstract: ZnS nanostructures have been synthesized by simple wet chemical route and annealed at two different temperatures of 50 o C and 180 o C. From the measurements of transmission electron microscopy and contact-mode atomic force microscopy, it is found that annealed temperature changes the morphology from nanoparticles to nanorods. The optical properties of the synthesized ZnS nanomaterial have been characterized by UV-visible absorption spectroscopy and photoluminescence spectroscopy. The structural and elemental analyses were carried out by powder X-ray diffraction pattern and energy dispersive X-ray absorption spectroscopy, respectively. Absorption edge of the nanoparticles (295 nm) and nanorods (326 nm) was shifted towards shorter wavelength compared to bulk ZnS (337 nm) due to the quantum confinement effect.

  17. Effects of sintering temperature on structural and electrical transport properties of zinc ferrites prepared by sol-gel route

    International Nuclear Information System (INIS)

    Anis-ur-Rehman, M.; Malik, M.A.; Ahmad, I.; Nasir, S.; Mubeen, M.; Abdullah, A.

    2011-01-01

    The effects of sintering temperature on the structural and electrical transport properties of nanocrystalline zinc ferrites are reported. The zinc ferrites were prepared by WOWS sol-gel synthesis route. The prepared sample was sintered at temperatures 500 deg. C, 700 deg. C and 900 deg. C respectively for 2 h. X-ray Diffraction (XRD) technique was used to describe the structural properties. The crystallite size, lattice parameters and porosity of samples were measured from the analysis of XRD data. The average crystallite size for each sample was measured using the Scherrer formula by considering the most intense (3 1 1) peak. The dielectric constant (e), dielectric loss tangent (tan theta ) and AC electrical conductivity of nanocrystalline Zn ferrites are investigated as a function of frequency and sintering temperature. All the electrical properties are explained in accordance with MaxwellWagner model and Koops phenomenological theory. (author)

  18. Synthetic routes to a nanoscale inorganic cluster [Ga13(μ3-OH)6(μ2-OH)18(H2O)](NO3)15 evaluated by solid-state 71Ga NMR

    International Nuclear Information System (INIS)

    Hammann, Blake A.; Marsh, David A.; Ma, Zayd L.; Wood, Suzannah R.; Eric West, Michael; Johnson, Darren W.; Hayes, Sophia E.

    2016-01-01

    Solid-state 71 Ga NMR was used to characterize a series of [Ga 13 (μ 3 -OH) 6 (μ 2 -OH) 18 (H 2 O)](NO 3 ) 15 “Ga 13 ” molecular clusters synthesized by multiple methods. These molecular clusters are precursors to thin film electronics and may be employed in energy applications. The synthetic routes provide varying levels of impurities in the solid phase, and these impurities often elude traditional characterization techniques such as powder X-ray diffraction and Raman spectroscopy. Solid-state NMR can provide a window into the gallium species even in amorphous phases. This information is vital in order to prevent the impurities from causing defect sites in the corresponding thin films upon gelation and condensation (polymerization) of the Ga 13 clusters. This work demonstrates the resolving power of solid-state NMR to evaluate structure and synthetic quality in the solid state, and the application of high-field NMR to study quadrupolar species, such as 71 Ga. - Graphical abstract: The various synthetic routes and 71 Ga solid-state NMR spectra of the nanoscale inorganic cluster [Ga 13 (μ 3 -OH) 6 (μ 2 -OH) 18 (H 2 O)](NO 3 ) 15 . - Highlights: • Solid-state 71 Ga NMR of hydroxo-aquo metal clusters and the impurities present. • High-field NMR capability allows for quadrupolar species, such as 71 Ga, to be routinely studied. • Efficient and environmentally friendly synthetic routes have been developed to prepare hydroxo-aquo metal clusters.

  19. Optical and magneto-optical properties of zinc-oxide nanostructures grown by the low-temperature chemical route

    Science.gov (United States)

    Willander, M.; Alnoor, H.; Savoyant, A.; Adam, Rania E.; Nur, O.

    2018-02-01

    We demonstrate that the low temperature synthesis chemical route can be utilized to control the functionality of zinc oxide (ZnO) nanoparticles (NPs) and nanorods (NRs) for optical and magneto-optical performance. Different structural, optical, electro- and magneto-optical results will be displayed and analyzed. In the first part, we show how high quality ZnO NPs can be efficient for photodegradation using ultra-violet radiation. In the second part we will present our recent results on the control of the core defects in cobalt doped ZnO NR. Here and by using electron paramagnetic resonance (EPR) measurements, the substitution of Co2+ ions in the ZnO NRs crystal is shown. The relation between the incorporation and core defects concentration will be discussed. The findings give access to the magnetic anisotropy of ZnO NRs grown by the low temperature chemical route and can lead to demonstrate room temperature ferromagnetism in nanostructures with potential for different device applications.

  20. Novel Routes for Sintering of Ultra-high Temperature Ceramics and their Properties

    Science.gov (United States)

    2014-10-31

    Structural investigation was carried out on metallographic microscope MIM–10, x-ray phase analysis– x-ray device DRON –2. Microhardness was measured by MPT...high- temperature X-ray diffractometer DRON -UM1 with high-temperature device UVD- 2000 (temperature interval 290-830K) and monochromatic Cu-Kα

  1. Synthesis of indium oxide cubic crystals by modified hydrothermal route for application in room temperature flexible ethanol sensors

    Energy Technology Data Exchange (ETDEWEB)

    Seetha, M., E-mail: seetha.phy@gmail.com [Department of Physics, SRM University, Kattankulathur, Kancheepuram Dt 603 203 (India); Meena, P. [Department of Physics, PSGR Krishnammal College for Women, Coimbatore 641 046 (India); Mangalaraj, D., E-mail: dmraj800@yahoo.com [DRDO-BU Centre for Life Sciences, Bharathiar University Campus, Coimbatore (India); Department of Nanoscience and Technology, Bharathiar University, Coimbatore 641 014 (India); Masuda, Yoshitake [National Institute of Advanced Industrial Science and Technology (AIST), Nagoya 463-8560 (Japan); Senthil, K. [School of Advanced Materials Science and Engineering, Sungkyunkwan University (Suwon Campus), Cheoncheon-dong 300, Jangan-gu, Suwon 440-746 (Korea, Republic of)

    2012-03-15

    Highlights: Black-Right-Pointing-Pointer For the first time HMT is used in the preparation of indium oxide. Black-Right-Pointing-Pointer HMT itself acts as base for the precursor and results in cubic indium hydroxide. Black-Right-Pointing-Pointer Modified hydrothermal route used for the preparation of cubic indium oxide crystals. Black-Right-Pointing-Pointer As a new approach a composite film synthesized with prepared indium oxide. Black-Right-Pointing-Pointer Film showed good response to ethanol vapours with quick response and recovery times. - Abstract: Indium oxide cubic crystals were prepared by using hexamethylenetetramine and indium chloride without the addition of any structure directing agents. The chemical route followed in the present work was a modified hydrothermal synthesis. The average crystallite size of the prepared cubes was found to be 40 nm. A blue emission at 418 nm was observed at room temperature when the sample was excited with a 380 nm Xenon lamp. This emission due to oxygen vacancies made the material suitable for gas sensing applications. The synthesized material was made as a composite film with polyvinyl alcohol which was more flexible than the films prepared on glass substrates. This flexible film was used as a sensing element and tested with ethanol vapours at room temperature. The film showed fast response as well as recovery to ethanol vapours with a sensor response of about 1.4 for 100 ppm of the gas.

  2. Synthesis of indium oxide cubic crystals by modified hydrothermal route for application in room temperature flexible ethanol sensors

    International Nuclear Information System (INIS)

    Seetha, M.; Meena, P.; Mangalaraj, D.; Masuda, Yoshitake; Senthil, K.

    2012-01-01

    Highlights: ► For the first time HMT is used in the preparation of indium oxide. ► HMT itself acts as base for the precursor and results in cubic indium hydroxide. ► Modified hydrothermal route used for the preparation of cubic indium oxide crystals. ► As a new approach a composite film synthesized with prepared indium oxide. ► Film showed good response to ethanol vapours with quick response and recovery times. - Abstract: Indium oxide cubic crystals were prepared by using hexamethylenetetramine and indium chloride without the addition of any structure directing agents. The chemical route followed in the present work was a modified hydrothermal synthesis. The average crystallite size of the prepared cubes was found to be 40 nm. A blue emission at 418 nm was observed at room temperature when the sample was excited with a 380 nm Xenon lamp. This emission due to oxygen vacancies made the material suitable for gas sensing applications. The synthesized material was made as a composite film with polyvinyl alcohol which was more flexible than the films prepared on glass substrates. This flexible film was used as a sensing element and tested with ethanol vapours at room temperature. The film showed fast response as well as recovery to ethanol vapours with a sensor response of about 1.4 for 100 ppm of the gas.

  3. Routes to High-Temperature Superconductivity: A Lesson from FeSe/SrTiO3

    Science.gov (United States)

    Lee, Dung-Hai

    2018-03-01

    Raising the superconducting transition temperature to a point where applications are practical is one of the most important challenges in science. In this review, we aim at gaining insights on the Tc controlling factors for a particular high-temperature superconductor family - the FeSe-based superconductors. In particular, we discuss the mechanisms by which the Cooper pairing temperature is enhanced from ˜8 K in bulk FeSe to ˜80 K in the interface between an atomic layer of FeSe and SrTiO3. This includes the experimental hints and the theoretical simulation of the involved mechanisms. We end by applying these insights to suggest some possible high-temperature superconducting systems.

  4. High-performance zno transistors processed via an aqueous carbon-free metal oxide precursor route at temperatures between 80-180 °c

    KAUST Repository

    Lin, Yenhung; Faber, Hendrik; Zhao, Kui; Wang, Qingxiao; Amassian, Aram; McLachlan, Martyn A.; Anthopoulos, Thomas D.

    2013-01-01

    An aqueous and carbon-free metal-oxide precursor route is used in combination with a UV irradiation-assisted low-temperature conversion method to fabricate low-voltage ZnO transistors with electron mobilities exceeding 10 cm2/Vs at temperatures <

  5. Possibilities and limitations of fast temperature programming as a route towards fast GC

    NARCIS (Netherlands)

    Deursen, van M.M.; Beens, J.; Cramers, C.A.M.G.; Janssen, J.G.M.

    1999-01-01

    One possible way to speed up a gas chromatographic analysis is the application of fast temperature programming by using resistive heating techniques. With this heating technique programming rates up to 20° per second can be reached. A relative standard deviation of retention times better than 0.2%

  6. Synthetic fuel production via carbon neutral cycles with high temperature nuclear reactors as a power source

    Energy Technology Data Exchange (ETDEWEB)

    Konarek, E.; Coulas, B.; Sarvinis, J. [Hatch Ltd., Mississauga, Ontario (Canada)

    2016-06-15

    This paper analyzes a number of carbon neutral cycles, which could be used to produce synthetic hydrocarbon fuels. Synthetic hydrocarbons are produced via the synthesis of Carbon Monoxide and Hydrogen. The . cycles considered will either utilize Gasification processes, or carbon capture as a source of feed material. In addition the cycles will be coupled to a small modular Nuclear Reactor (SMR) as a power and heat source. The goal of this analysis is to reduce or eliminate the need to transport diesel and other fossil fuels to remote regions and to provide a carbon neutral, locally produced hydrocarbon fuel for remote communities. The technical advantages as well as the economic case are discussed for each of the cycles presented. (author)

  7. Synthetic fuel production via carbon neutral cycles with high temperature nuclear reactors as a power source

    International Nuclear Information System (INIS)

    Konarek, E.; Coulas, B.; Sarvinis, J.

    2016-01-01

    This paper analyzes a number of carbon neutral cycles, which could be used to produce synthetic hydrocarbon fuels. Synthetic hydrocarbons are produced via the synthesis of Carbon Monoxide and Hydrogen. The . cycles considered will either utilize Gasification processes, or carbon capture as a source of feed material. In addition the cycles will be coupled to a small modular Nuclear Reactor (SMR) as a power and heat source. The goal of this analysis is to reduce or eliminate the need to transport diesel and other fossil fuels to remote regions and to provide a carbon neutral, locally produced hydrocarbon fuel for remote communities. The technical advantages as well as the economic case are discussed for each of the cycles presented. (author)

  8. A Novel Synthetic Route for Green-emitting Zn{sub 2-x}Mn{sub x}SiO{sub 4} Phosphor using Colloidal Silica

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Seong Gu [Hoseo University, Asan (Korea, Republic of); Park, Jung Chul [Silla University, Busan (Korea, Republic of)

    2010-11-15

    We have synthesized Mn-doped Zn{sub 2}SiO{sub 4} phosphors by solgel method using colloidal silica. The adsorption characteristics of the citric acid molecules onto the silica surfaces enables us to use colloidal silica as a Si-source instead of TEOS which is generally utilized for the fine particle synthesis of the silicate based compounds. At a very low temperature (800 .deg. C), we could obtain the single phase of Zn{sub 2}SiO{sub 4}, which is remarkable compared to that of the solid state reaction (about 1300 .deg. C). The mean size of particles prepared at 800 .deg. C, 900 .deg. C, and 1000 .deg. C is 100 nm, 200 nm, and 400 nm, respectively. The PL intensity of Zn{sub 1.92}Mn{sub 0.08}SiO{sub 4} prepared at different temperature between 800 .deg. C and 1200 .deg. C, increases as the synthetic temperature rises up. Moreover, the PL intensity of Zn{sub 1.92}Mn{sub 0.08}SiO{sub 4} prepared at 1200 .deg. C is remarkable compared to that of the commercial Zn{sub 2}SiO{sub 4} : Mn (Kasei company, Japan). The PL intensity for Zn{sub 1.92}Mn{sub 0.08}SiO{sub 4} as a function of colloidal silica content, do not induces a considerable change in PL intensity, but a considerable modification in the morphology of particles. It might be said that colloidal silica is a promising chemical as a Si-source for the synthesis of fine particle of silicate compounds, instead of TEOS. The Mn{sup 2+}-doped Zn{sub 2}SiO{sub 4} phosphor has been used as a luminescent material for lamp and plasma panel display because of its high-luminescent efficiency and chemical stability. The emission of the Zn{sub 2-x}Mn{sub x}SiO{sub 4} at 520 nm is attributed to d-level spin-forbidden transition for Mn(II). According to the earlier literatures, the photoluminescence (PL) process of Zn{sub 2-x}Mn{sub x}SiO{sub 4} phosphors has been characterized by the transition of 3d{sup 5} electrons in the manganese ion acting as an activation center in the willemite structure. In particular, the transition

  9. A chemical route to room-temperature synthesis of nanocrystalline TiO2 thin films

    International Nuclear Information System (INIS)

    Pathan, Habib M.; Kim, Woo Young; Jung, Kwang-Deog; Joo, Oh-Shim

    2005-01-01

    A lot of methods are developed for the deposition of TiO 2 thin films; however, in each of these methods as-deposited films are amorphous and need further heat treatment at high temperature. In the present article, a chemical bath deposition (CBD) method was used for the preparation of TiO 2 thin films. We investigated nanocrystalline TiO 2 thin films using CBD at room temperature onto glass and ITO coated glass substrate. The films were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and high-resolution transmission electron microscopy (HRTEM) techniques. The chemically synthesized films were nanocrystalline and composed of crystal grains of 2-3 nm

  10. Controllable synthesis of spindle-like ZnO nanostructures by a simple low-temperature aqueous solution route

    International Nuclear Information System (INIS)

    Lu Hongxia; Zhao Yunlong; Yu Xiujun; Chen Deliang; Zhang Liwei; Xu Hongliang; Yang Daoyuan; Wang Hailong; Zhang Rui

    2011-01-01

    Spindle-like ZnO nanostructures were successfully synthesized through direct precipitation of zinc acetate aqueous solution at 60 deg. C. Phase structure, morphology and microstructure of the products were investigated by X-ray diffraction, TG-DTA, FTIR and field emission scanning electron microscopy (FESEM). Result showed that hexagonal wurtzite structure ZnO nanostructures with about 100 nm in diameter and 100-200 nm in length were obtained. HMTA acted as a soft template in the process and played an important role in the formation of spindle-like ZnO nanostructures. Meanwhile, different morphologies were also obtained by altering synthetic temperature, additional agents and the ratios of Zn 2+ /OH - . Possible mechanism for the variations of morphology with synthesis parameters was also discussed in this paper.

  11. Effect of new type of synthetic waxes on reduced production and compaction temperature of asphalt mixture with reclaimed asphalt

    Science.gov (United States)

    Valentová, Tereza; Benešová, Lucie; Mastný, Jan; Valentin, Jan

    2017-09-01

    Lower mixing and paving temperatures of asphalt mixtures, which are an important issue in recent years, with respect to increased energy demand of civil engineering structures during their processing, allow reduction of this demand and result in minimized greenhouse gas production. In present time, there are many possibilities how to achieve reduction of production temperature during the mixing and paving of an asphalt mixture. The existing solutions distinguish in target operating temperature behaviour which has to be achieved in terms of good workability. This paper is focused on technical solutions based on use of new types of selected synthetic and bio-based waxes. In case of bio-based additive sugar cane wax was used, which is free of paraffins and is reclaimed as waste product during processing of sugar cane. The used waxes are added to bituminous binder in form of free-flowing granules or fine-grained powder. Synthetic waxes are represented by new series of Fischer-Tropsch wax in form of fine granules as well as by polyethylene waxes in form of fine-grained powder or granules. Those waxes were used to modify a standard paving grade bitumen dosed into asphalt mixture of ACsurf type containing up to 30 % of reclaimed asphalt (RA).

  12. Low temperature route synthesis of SiC–Al2O3 hetero-structural nanofibers

    International Nuclear Information System (INIS)

    Dai, Xiao; Wang, Hao; Cao, Fengfeng; Yi, Qinghua; Cong, Shan; Wang, Yun; Song, Pingyuan; Zhai, Pengfei; Zou, Guifu; Dong, Chao

    2014-01-01

    SiC–Al 2 O 3 hetero-structural nanofibers have been synthesized by the chemical solution approach at 200 ° C. The diameters of nanofibers are in the range of 60–100 nm while the lengths are from tens of micrometers to hundreds of micrometers. The microstructural analysis shows that the fibers possess a like-epitaxial relationship between (104) of hexagonal Al 2 O 3 and (111) of cubic SiC. Additionally, the optical investigation of the nanofibers suggests there are some defects in the low annealing temperature synthesized SiC–Al 2 O 3 nanofibers. (paper)

  13. Biological and Biomimetic Low-Temperature Routes to Materials for Energy Applications

    Energy Technology Data Exchange (ETDEWEB)

    Morse, Daniel E. [Univ. of California, Santa Barbara, CA (United States). Inst. for Collaborative Biotechnologies

    2016-08-29

    New materials are needed to significantly improve the efficiencies of energy harnessing, transduction and storage, yet the synthesis of advanced composites and multi-metallic semiconductors with nanostructures optimized for these functions remains poorly understood and even less well controlled. To help address this need, we proposed three goals: (1) to further investigate the hierarchical structure of the biologically synthesized silica comprising the skeletal spicules of sponges that we discovered, to better resolve the role and mechanism of templating by the hierarchically assembled silicatein protein filament; (2) to extend our molecular and genetic analyses and engineering of silicatein, the self-assembling, structure-directing, silica-synthesizing enzyme we discovered and characterized, to better understand and manipulate the catalysis and templating of semiconductor synthesis,; and (3) to further investigate, scale up and harness the biologically inspired, low-temperature, kinetically controlled catalytic synthesis method we developed (based on the mechanism we discovered in silicatein) to investigate the kinetic control of the structure-function relationships in magnetic materials, and develop new materials for energy applications. The bio-inspired catalytic synthesis method we have developed is low-cost, low temperature, and operates without the use of polluting chemicals. In addition to direct applications for improvement of batteries and fuel cells, the broader impact of this research includes a deeper fundamental understanding of the factors governing kinetically controlled synthesis and its control of the emergent nanostructure and performance of a wide range of nanomaterials for energy applications.

  14. Porous organic polymers with anchored aldehydes: A new platform for post-synthetic amine functionalization en route for enhanced CO2 adsorption properties

    KAUST Repository

    Guillerm, Vincent; Weselinski, Lukasz Jan; Al Kordi, Mohamed; Haja Mohideen, Mohamed Infas; Belmabkhout, Youssef; Cairns, Amy; Eddaoudi, Mohamed

    2014-01-01

    A novel porous organic polymer has been synthesized using the molecular building block approach to deliberately encompass aldehyde functionalities amenable to post functionalization. The resultant porous framework allows a facile, one-step quantitative and post-synthetic functionalization by amines, permitting enhanced CO2 sorption properties. © 2014 The Royal Society of Chemistry.

  15. A facile route for irreversible bonding of plastic-PDMS hybrid microdevices at room temperature.

    Science.gov (United States)

    Tang, Linzhi; Lee, Nae Yoon

    2010-05-21

    Plastic materials do not generally form irreversible bonds with poly(dimethylsiloxane) (PDMS) regardless of oxygen plasma treatment and a subsequent thermal process. In this paper, we perform plastic-PDMS bonding at room temperature, mediated by the formation of a chemically robust amine-epoxy bond at the interfaces. Various plastic materials, such as poly(methylmethacrylate) (PMMA), polycarbonate (PC), polyimide (PI), and poly(ethylene terephthalate) (PET) were adopted as choices for plastic materials. Irrespective of the plastic materials used, the surfaces were successfully modified with amine and epoxy functionalities, confirmed by the surface characterizations such as water contact angle measurements and X-ray photoelectron spectroscopy (XPS), and chemically robust and irreversible bonding was successfully achieved within 1 h at room temperature. The bonding strengths of PDMS with PMMA and PC sheets were measured to be 180 and 178 kPa, respectively, and their assemblies containing microchannel structures endured up to 74 and 84 psi (510 and 579 kPa) of introduced compressed air, respectively, without destroying the microdevices, representing a robust and highly stable interfacial bonding. In addition to microchannel-molded PDMS bonded with flat plastic substrates, microchannel-embossed plastics were also bonded with a flat PDMS sheet, and both types of bonded assemblies displayed sufficiently robust bonding, tolerating an intense influx of liquid whose per-minute injection volume was nearly 1000 to 2000 times higher than the total internal volume of the microchannel used. In addition to observing the bonding performance, we also investigated the potential of surface amine and epoxy functionalities as durable chemical adhesives by observing their storage-time-dependent bonding performances.

  16. High temperature, high heating rate carbonisation - a route to new forms of carbon

    International Nuclear Information System (INIS)

    Wilson, M. A.

    1998-01-01

    Carbonisation (more properly called pyrolysis) of coal has long been an important process for the good of mankind. It is relevant to coke making, the production of briquettes, the formation of specialist carbons such as anodes and other more exotic carbon forms. During heating, volatiles are produced and compounds containing carbon, hydrogen and oxygen are lost. The yield of volatiles and residues (inappropriately called char) depends on the rank of the coal used, the temperature of pyrolysis, and the heating rate. Mathematical models have been devised to account for loss of weight at constant heating rate, gas evolution, plasticity, swelling and changes in density, and other physical properties. Moreover chemical models of pyrolysis have also been devised. When carbon radicals are formed they may polymerize to form, if the correct number of hexagons or pentagons are present, a closed structure, such as the soccerball molecules. An account is given on the work carried out in Australia, at the University of Technology where the scientists were successful in identifying and then preparing buckyballs from coal rather than expensive graphite, first by laser pyrolysis and then by plasma arcing

  17. Unconventional route to encapsulated ultrasmall gold nanoparticles for high-temperature catalysis.

    Science.gov (United States)

    Zhang, Tingting; Zhao, Hongyu; He, Shengnan; Liu, Kai; Liu, Hongyang; Yin, Yadong; Gao, Chuanbo

    2014-07-22

    Ultrasmall gold nanoparticles (us-AuNPs, gold hydroxide nanoparticles, which have excellent affinity to silica, then carrying out controllable silica coating in reverse micelles, and finally converting gold hydroxide particles into well-protected us-AuNPs. With a single-core/shell configuration that prevents sintering of nearby us-AuNPs and amino group modification of the Au/SiO2 interface that provides additional coordinating interactions, the resulting us-AuNP@SiO2 nanospheres are highly stable at high temperatures and show high activity in catalytic CO oxidation reactions. A dramatic and continuous increase in the catalytic activity has been observed when the size of the us-AuNPs decreases from 2.3 to 1.5 nm, which reflects the intrinsic size effect of the Au nanoparticles on an inert support. The synthesis scheme described in this work is believed to be extendable to many other ultrasmall metal@oxide nanostructures for much broader catalytic applications.

  18. Exploration of the phase diagram of liquid water in the low-temperature metastable region using synthetic fluid inclusions

    DEFF Research Database (Denmark)

    Qiu, Chen; Krüger, Yves; Wilke, Max

    2016-01-01

    water with a density of 0.921 kg/m3 remains in a homogeneous state during cooling down to the temperaure of −30.5 °C, where it is transformed into ice whose density corresponds to zero pressure. iii) ice melting. Ice melting temperatures of up to 6.8 °C were measured in absence of the vapour bubble, i......We present new experimental data of the low-temperature metastable region of liquid water derived from high-density synthetic fluid inclusions (996−916 kg/m3) in quartz. Microthermometric measurements include: i) Prograde (upon heating) and retrograde (upon cooling) liquid-vapour homogenisation. We...

  19. Study of Hopcalite (CuMnOx Catalysts Prepared Through A Novel Route for the Oxidation of Carbon Monoxide at Low Temperature

    Directory of Open Access Journals (Sweden)

    Subhashish Dey

    2017-10-01

    How to Cite: Dey, S., Dhal, G.C., Mohan, D., Prasad, R. (2017. Study of Hopcalite (CuMnOx Catalysts Prepared through A Novel Route for the Oxidation of Carbon Monoxide at Low Temperature. Bulletin of Chemical Reaction Engineering & Catalysis, 12 (3: 393-407 (doi:10.9767/bcrec.12.3.882.393-407

  20. High-performance zno transistors processed via an aqueous carbon-free metal oxide precursor route at temperatures between 80-180 °c

    KAUST Repository

    Lin, Yenhung

    2013-06-25

    An aqueous and carbon-free metal-oxide precursor route is used in combination with a UV irradiation-assisted low-temperature conversion method to fabricate low-voltage ZnO transistors with electron mobilities exceeding 10 cm2/Vs at temperatures <180°C. Because of its low temperature requirements the method allows processing of high-performance transistors onto temperature sensitive substrates such as plastic. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Photoelectrochemical properties of ZnO nanocrystals/MEH-PPV composite: The effects of nanocrystals synthetic route, film deposition and electrolyte composition

    Energy Technology Data Exchange (ETDEWEB)

    Petrella, A. [Dipartimento di Ingegneria Civile, Ambientale, del Territorio, Edile e Chimica, Politecnico di Bari, Via Orabona 4, 70125 Bari (Italy); Curri, M.L.; Striccoli, M. [CNR IPCF Sez. Bari c/o Dip. Chimica, Università di Bari, Via Orabona 4, 70126 Bari (Italy); Agostiano, A. [Dipartimento di Chimica, Università di Bari, via Orabona 4, 70126 Bari (Italy); CNR IPCF Sez. Bari c/o Dip. Chimica, Università di Bari, Via Orabona 4, 70126 Bari (Italy); Cosma, P., E-mail: pinalysa.cosma@uniba.it [Dipartimento di Chimica, Università di Bari, via Orabona 4, 70126 Bari (Italy); CNR IPCF Sez. Bari c/o Dip. Chimica, Università di Bari, Via Orabona 4, 70126 Bari (Italy)

    2015-11-30

    This paper reports a study on the photoelectrochemical processes occurring at the interface of ZnO nanocrystals/MEH-PPV composites. Colloidal chemical routes were used to obtain size controlled non-hydrolytic ZnO nanocrystals (NCs) dispersible in organic solvents, while a low molecular weight poly[2-methoxy-5-(2′-ethyl-hexyloxy)phenylene vinylene] (MEH-PPV), characterized by high degree of structural order, was synthesized via an organometallic method. The optical properties of the nanocomposite material were comprehensively investigated on solution and on films deposited by spin coating. Remarkably, a significant fluorescence quenching of the polymer at the MEH-PPV/ZnO junction was observed. Photoelectrochemical measurements demonstrated that the photoactivity of the composite material was significantly improved in the case of non-hydrolytic NCs with respect to hydrolytic route prepared ZnO. Moreover, the effective role of the organic/inorganic blend to improve the charge transfer with respect to the double layer hetero-junction was confirmed, thanks to the extended interfaces which enable an effective electron transfer between the hetero-junction components. The system was also studied at different film thicknesses and electrolyte compositions. The results indicated that film photoactivity increased with film thickness up to 300 nm due to the presence of a large number of interfaces, while the change of cation size influenced the ionic conductivity through the nanocomposite film. It was shown that efficient photoconductivity requires not only efficient charge separation, but also efficient transport of the carriers to the electrodes without recombination. - Highlights: • The photoelectrochemical processes at ZnO nanocrystals/MEH-PPV hetero-junction were studied. • Fluorescence quenching of the polymer at the MEH-PPV/ZnO interface was observed. • Non-hydrolytic ZnO junction showed higher photocurrents than hydrolytic equivalent. • The blends showed

  2. Photoelectrochemical properties of ZnO nanocrystals/MEH-PPV composite: The effects of nanocrystals synthetic route, film deposition and electrolyte composition

    International Nuclear Information System (INIS)

    Petrella, A.; Curri, M.L.; Striccoli, M.; Agostiano, A.; Cosma, P.

    2015-01-01

    This paper reports a study on the photoelectrochemical processes occurring at the interface of ZnO nanocrystals/MEH-PPV composites. Colloidal chemical routes were used to obtain size controlled non-hydrolytic ZnO nanocrystals (NCs) dispersible in organic solvents, while a low molecular weight poly[2-methoxy-5-(2′-ethyl-hexyloxy)phenylene vinylene] (MEH-PPV), characterized by high degree of structural order, was synthesized via an organometallic method. The optical properties of the nanocomposite material were comprehensively investigated on solution and on films deposited by spin coating. Remarkably, a significant fluorescence quenching of the polymer at the MEH-PPV/ZnO junction was observed. Photoelectrochemical measurements demonstrated that the photoactivity of the composite material was significantly improved in the case of non-hydrolytic NCs with respect to hydrolytic route prepared ZnO. Moreover, the effective role of the organic/inorganic blend to improve the charge transfer with respect to the double layer hetero-junction was confirmed, thanks to the extended interfaces which enable an effective electron transfer between the hetero-junction components. The system was also studied at different film thicknesses and electrolyte compositions. The results indicated that film photoactivity increased with film thickness up to 300 nm due to the presence of a large number of interfaces, while the change of cation size influenced the ionic conductivity through the nanocomposite film. It was shown that efficient photoconductivity requires not only efficient charge separation, but also efficient transport of the carriers to the electrodes without recombination. - Highlights: • The photoelectrochemical processes at ZnO nanocrystals/MEH-PPV hetero-junction were studied. • Fluorescence quenching of the polymer at the MEH-PPV/ZnO interface was observed. • Non-hydrolytic ZnO junction showed higher photocurrents than hydrolytic equivalent. • The blends showed

  3. Cold adaptation and replicable microbial community development during long-term low-temperature anaerobic digestion treatment of synthetic sewage.

    Science.gov (United States)

    Keating, C; Hughes, D; Mahony, T; Cysneiros, D; Ijaz, U Z; Smith, C J; O'Flaherty, V

    2018-07-01

    The development and activity of a cold-adapting microbial community was monitored during low-temperature anaerobic digestion (LtAD) treatment of wastewater. Two replicate hybrid anaerobic sludge bed-fixed-film reactors treated a synthetic sewage wastewater at 12°C, at organic loading rates of 0.25-1.0 kg chemical oxygen demand (COD) m-3 d-1, over 889 days. The inoculum was obtained from a full-scale anaerobic digestion reactor, which was operated at 37°C. Both LtAD reactors readily degraded the influent with COD removal efficiencies regularly exceeding 78% for both the total and soluble COD fractions. The biomass from both reactors was sampled temporally and tested for activity against hydrolytic and methanogenic substrates at 12°C and 37°C. Data indicated that significantly enhanced low-temperature hydrolytic and methanogenic activity developed in both systems. For example, the hydrolysis rate constant (k) at 12°C had increased 20-30-fold by comparison to the inoculum by day 500. Substrate affinity also increased for hydrolytic substrates at low temperature. Next generation sequencing demonstrated that a shift in a community structure occurred over the trial, involving a 1-log-fold change in 25 SEQS (OTU-free approach) from the inoculum. Microbial community structure changes and process performance were replicable in the LtAD reactors.

  4. Dose-dependent optically stimulated luminescence of synthetic quartz at room temperature

    International Nuclear Information System (INIS)

    Kale, Y.D.; Gandhi, Y.H.; Gartia, R.K.

    2008-01-01

    Physical conditions such as annealing temperature, duration of annealing, ionizing radiation, etc., play a significant role in the applications of optically stimulated luminescence (OSL) dating as well as OSL dosimetry. Many efforts are made to understand the effect of these physical parameters on quartz specimens owing to its use in such applications. Such factors induce changes in OSL decay pattern. The definite correlation between color centers and luminescence sensitivity can be established on account of such pre-treatments to the specimen. The purpose of present investigations is to study the effect of ionizing radiation under identical physical conditions on OSL properties measured at room temperature. The shapes of decay curve and dose-response data are considered for this purpose. This study can reveal the changes in color centers in response to the pre-conditions to the specimen. It was found that the OSL decay remains slow and OSL properties change systematically with the rise in beta dose up to a critical dose; however, it changes the pattern when the beta exposure to the specimen was increased higher than the critical dose. This critical dose was found to be different for different temperature of annealing. The shape of decay curve up to the critical dose was also studied by considering the difference of OSL intensities between two successive durations from the observed OSL decay data. The results are explained based on the changes in available shallow traps during OSL measurement at room temperature with changes in pre-conditions to the specimens. The results also have been confirmed with the corresponding changes in ESR signals

  5. Thermal conductivity of the cryoprotective cocktail DP6 in cryogenic temperatures, in the presence and absence of synthetic ice modulators.

    Science.gov (United States)

    Ehrlich, Lili E; Malen, Jonathan A; Rabin, Yoed

    2016-10-01

    The thermal conductivity of the cryoprotective agent (CPA) cocktail DP6 in combination with synthetic ice modulators (SIMs) is measured in this study, using a transient hot-wire method. DP6 is a mixture of 3 M dimethyl sulfoxide (DMSO) and 3 M propylene glycol, which received significant attention in the cryobiology community in recent years. Tested SIMs include 6% 1,3Cyclohexanediol, 6% 2,3Butanediol, and 12% PEG400 (percentage by volume). This study integrates the scanning cryomacroscope for visual verification of crystallization and vitrification events. It is demonstrated that the thermal conductivity of the vitrifying CPA cocktail decreases monotonically with the decreasing temperature down to -180 °C. By contrast, the thermal conductivity of the crystalline material increases with decreasing temperature in the same temperature range. Results of this study demonstrate that the thermal conductivity may vary by three fold between the amorphous and crystalline phases of DP6 below the glass transition temperature of DP6 (Tg = -119 °C). The selected SIMs demonstrate the ability to inhibit crystallization in DP6, even at subcritical cooling rates. An additional ice suppression capability is observed by the Euro-Collins as a vehicle solution, disproportionate to its volume ratio in the cocktail. The implication of the observed thermal conductivity differences between the amorphous and crystalline phases of the same cocktail on cryopreservation simulations is significant in some cases and must be taken into account in thermal analyses of cryopreservation protocols. Copyright © 2016. Published by Elsevier Inc.

  6. High-temperature gas reactor (HTGR) market assessment, synthetic fuels analysis

    International Nuclear Information System (INIS)

    1980-08-01

    This study is an update of assessments made in TRW's October 1979 assessment of overall high-temperature gas-cooled reactor (HTGR) markets in the future synfuels industry (1985 to 2020). Three additional synfuels processes were assessed. Revised synfuel production forecasts were used. General environmental impacts were assessed. Additional market barriers, such as labor and materials, were researched. Market share estimates were used to consider the percent of markets applicable to the reference HTGR size plant. Eleven HTGR plants under nominal conditions and two under pessimistic assumptions are estimated for selection by 2020. No new HTGR markets were identified in the three additional synfuels processes studied. This reduction in TRW's earlier estimate is a result of later availability of HTGR's (commercial operation in 2008) and delayed build up in the total synfuels estimated markets. Also, a latest date for HTGR capture of a synfuels market could not be established because total markets continue to grow through 2020. If the nominal HTGR synfuels market is realized, just under one million tons of sulfur dioxide effluents and just over one million tons of nitrous oxide effluents will be avoided by 2020. Major barriers to a large synfuels industry discussed in this study include labor, materials, financing, siting, and licensing. Use of the HTGR intensifies these barriers

  7. Long-term changes in migration timing of Song Thrush Turdus philomelos at the southern Baltic coast in response to temperatures on route and at breeding grounds.

    Science.gov (United States)

    Redlisiak, Michał; Remisiewicz, Magdalena; Nowakowski, Jarosław K

    2018-05-26

    Climate warming causes the advancement of spring arrival of many migrant birds breeding in Europe, but the effects on their autumn migration are less known. We aimed to determine any changes in the timing of Song Thrush captured during spring and autumn migrations at the Polish Baltic coast from 1975 to 2014, and if these were related to long-term changes of temperature at their breeding grounds and migration routes. The timing of spring migration at Hel ringing station in 1975-2014 did not show long-term advance, but they had responded to environmental conditions on the year-to-year basis. The warmer the temperatures were in April on their migration route, the earlier were the dates of the median and the end of spring migration at Hel. The beginning of autumn migration at the Mierzeja Wiślana ringing station advanced by 5 days between 1975 and 2014. The warmer the April on route, and the July at the Song Thrushes' breeding grounds, the earlier young birds began autumn migration across the Baltic coast. We suggest this was a combined effect of adults' migration and breeding early during warm springs and young birds getting ready faster for autumn migration during warm summers. The average time span of 90% of the autumn migration was extended by 5 days, probably because of early migration of young birds from first broods and late of those from second broods enabled by warm springs and summers. The response of Song Thrushes' migration timing to temperatures on route and at the breeding grounds indicated high plasticity in the species and suggested it might adapt well to climate changes.

  8. Effect of temperature, pH, and water activity on Mucor spp. growth on synthetic medium, cheese analog and cheese.

    Science.gov (United States)

    Morin-Sardin, Stéphanie; Rigalma, Karim; Coroller, Louis; Jany, Jean-Luc; Coton, Emmanuel

    2016-06-01

    The Mucor genus includes a large number of ubiquitous fungal species. In the dairy environment, some of them play a technological role providing typical organoleptic qualities to some cheeses while others can cause spoilage. In this study, we compared the effect of relevant abiotic factors for cheese production on the growth of six strains representative of dairy technological and contaminant species as well as of a non cheese related strain (plant endophyte). Growth kinetics were determined for each strain in function of temperature, water activity and pH on synthetic Potato Dextrose Agar (PDA), and secondary models were fitted to calculate the corresponding specific cardinal values. Using these values and growth kinetics acquired at 15 °C on cheese agar medium (CA) along with three different cheese types, optimal growth rates (μopt) were estimated and consequently used to establish a predictive model. Contrarily to contaminant strains, technological strains showed higher μopt on cheese matrices than on PDA. Interestingly, lag times of the endophyte strain were strongly extended on cheese related matrices. This study offers a relevant predictive model of growth that may be used for better cheese production control but also raises the question of adaptation of some Mucor strains to the cheese. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Flexible synthetic routes to poison-frog alkaloids of the 5,8-disubstituted indolizidine-class I: synthesis of common lactam chiral building blocks and application to the synthesis of (--203A, (--205A, and (--219F

    Directory of Open Access Journals (Sweden)

    Spande Thomas F

    2007-09-01

    Full Text Available Abstract Background The 5,8-disubstituted indolizidines are the largest class of poison-frog alkaloids found in anuran skin, and are of considerable interest because of their inhibitory effects on the neuronal nicotinic acetylcholine receptors. Many synthetic strategies for the construction of this nucleus have been reported: however, a flexible route has not been reported to date. Results Synthesis of lactam chiral building blocks for the flexible synthesis of the title alkaloids has been achieved using a Michael-type conjugate addition reaction to a chiral cyclic enamine ester as the key step in constructing the trisubstituted piperidine ring system. To demonstrate the usefulness of these chiral building blocks, syntheses of (--203A, (--205A from 1, and (--219F from 2 have been achieved. Conclusion The total synthesis of (--203A, (--205A, and (--219F was achieved, and the absolute stereochemistry of natural 203A was determined to be 5S, 8R, 9S. In addition, the relative stereochemistry of natural 219F was determined.

  10. Evaluation of powder metallurgical processing routes for multi-component niobium silicide-based high-temperature alloys

    Energy Technology Data Exchange (ETDEWEB)

    Seemueller, Hans Christoph Maximilian

    2016-03-22

    Niobium silicide-based composites are potential candidates to replace nickel-base superalloys for turbine applications. The goal of this work was to evaluate the feasibility and differences in ensuing properties of various powder metallurgical processing techniques that are capable of manufacturing net-shape turbine components. Two routes for powder production, mechanical alloying and gas atomization were combined with compaction via hot isostatic pressing and powder injection molding.

  11. The nitrogen acceptor in 2H-Polytype synthetic MoS2. Frequency and temperature dependent ESR analysis

    International Nuclear Information System (INIS)

    Schoenaers, Ben; Stesmans, Andre; Afanas'ev, Valery V.

    2017-01-01

    In extending on recent electron spin resonance (ESR) work which has revealed the N acceptor (N substituting for S site) in 2H-polytype bulk synthetic MoS 2 , the dopant is extensively analyzed in terms of its frequency, temperature (T), and magnetic field B angular dependent ESR spectral characteristics. For B parallel c-axis, the multi-frequency analysis confirms the ESR spectrum as being composed of a 14 N hyperfine (hf) triplet with hf splitting constant A parallel = 14.7 ± 0.2 G (B parallel c-axis) and making up ∼74% of the total spectrum intensity, superimposed on a central line centered at about equal g-value [g parallel = 2.032(2)]. The presence of the latter signal, points to some non-uniformity in dopant distribution, that is, clustering, with about ∼26% of the total N response not originating from N incorporated in the preferred ''isolated'' dopant configuration. Angular dependent measurements reveal distinct anisotropy of the hf matrix, whereas ESR probing over a wide T-range exposes drastic signal broadening with increasing T above ∼150 K. Detailed study of the N acceptor signal intensity versus T at Q-band reveals an activation energy E a = 50 ± 10 meV, herewith consolidating the value reported initially. Besides unveiling the S-site substitutional N impurity as an appropriate p-type dopant for MoS 2 , the total of the ESR work establishes a basic frame of the N acceptor ESR characteristics, giving way for further in-depth theoretical perusal. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  12. SUPPLEMENTARY INFORMATION Green synthetic route for ...

    Indian Academy of Sciences (India)

    GDY13

    Catalyst synthesis. S3. 2. Catalyst characterisation Techniques. S3. 3. NH3-TPD of 0.1% Li/MgO. S3. 4. Proof for absence of external mass transfer resistance. S4. 5. Proof of absence of intra-particle resistance. S5. List of Figures: No. Title. Page No. Figure S1 10% NH3-TPD of 0.1% Li/MgO. S4. Figure S2 SEM of pure MgO.

  13. Synthetic Astrobiology

    Science.gov (United States)

    Rothschild, Lynn J.

    2017-01-01

    "Are we alone?" is one of the primary questions of astrobiology, and whose answer defines our significance in the universe. Unfortunately, this quest is hindered by the fact that we have only one confirmed example of life, that of earth. While this is enormously helpful in helping to define the minimum envelope for life, it strains credulity to imagine that life, if it arose multiple times, has not taken other routes. To help fill this gap, our lab has begun using synthetic biology - the design and construction of new biological parts and systems and the redesign of existing ones for useful purposes - as an enabling technology. One theme, the "Hell Cell" project, focuses on creating artificial extremophiles in order to push the limits for Earth life, and to understand how difficult it is for life to evolve into extreme niches. In another project, we are re-evolving biotic functions using only the most thermodynamically stable amino acids in order to understand potential capabilities of an early organism with a limited repertoire of amino acids.

  14. Molten salts activated by high-energy milling: A useful, low-temperature route for the synthesis of multiferroic compounds

    Energy Technology Data Exchange (ETDEWEB)

    Hernández-Ramírez, Anayantzin; Martínez-Luévanos, Antonia [Facultad de Ciencias Químicas, Universidad Autónoma de Coahuila, V. Carranza s/n, Saltillo, Coahuila 25280 (Mexico); Fuentes, Antonio F. [CINVESTAV Unidad Saltillo, Apdo. Postal 663, Saltillo, Coahuila 25000 (Mexico); Earth and Environmental Science, University of Michigan, 3514 C.C. Little Building, 1100 N. University Avenue, Ann Arbor, MI 48109-1005 (United States); Nelson, Anna-Gay D.; Ewing, Rodney C. [Earth and Environmental Science, University of Michigan, 3514 C.C. Little Building, 1100 N. University Avenue, Ann Arbor, MI 48109-1005 (United States); Montemayor, Sagrario M., E-mail: smmontemayor@gmail.com [Facultad de Ciencias Químicas, Universidad Autónoma de Coahuila, V. Carranza s/n, Saltillo, Coahuila 25280 (Mexico); Earth and Environmental Science, University of Michigan, 3514 C.C. Little Building, 1100 N. University Avenue, Ann Arbor, MI 48109-1005 (United States)

    2014-01-25

    Highlights: • The synthesis route purposed demonstrates the formation of BiFeO{sub 3} at only 500 °C. • The magnetic and ferroelectric properties are comparable to those of bulk BiFeO{sub 3}. • By this route, several phases in Bi{sub 1−x}La{sub x}FeO{sub 3} system are obtained at only 500 °C. • The route developed here could be useful to synthesize other perovskite-type oxides. -- Abstract: There are only a few multiferroic compounds, among which BiFeO{sub 3} is the most important. Research the synthesis of bismuth ferrite, with novel and improved magnetic and electrical properties, has been mainly based on the use of hydrothermal or sol gel methods. However, these methods require either rather extreme conditions or several steps for synthesis. We demonstrate that the use of molten salts, activated by high energy milling, results in pure nanometric BiFeO{sub 3}, LaFeO{sub 3} and intermediate phases in the Bi{sub 1−x}La{sub x}FeO{sub 3} system. The chemical reagents used are Bi(NO{sub 3}){sub 3}⋅5H{sub 2}O, La(NO{sub 3}){sub 3}⋅6H{sub 2}O, Fe(NO{sub 3}){sub 3}⋅9H{sub 2}O and NaOH. A brief milling process of the reagents creates an amorphous precursor and crystalline NaNO{sub 3}. The thermal treatment of the precursors, at 500 °C for two hours, produces a crystalline mixture of Bi{sub 1−x}La{sub x}FeO{sub 3} and NaNO{sub 3}. Simple washing eliminates the NaNO{sub 3}. The characterization of intermediates and final products, through thermal analysis, X-ray diffraction and scanning electronic microscopy, allows the inference of possible mechanism. In addition, vibrating sample magnetometry (VSM) and ferroelectric tests show the typical magnetic and electric polarization loops characteristic of these materials even when formed at the nano-scale.

  15. Radical polymerization of capillary bridges between micron-sized particles in liquid bulk phase as a low temperature route to produce porous solid materials.

    Science.gov (United States)

    Hauf, Katharina; Riazi, Kamran; Willenbacher, Norbert; Koos, Erin

    2017-10-01

    We present a generic and versatile low temperature route to produce macro-porous bodies with porosity and pore size distribution that are adjustable in a wide range. Capillary suspensions, where the minor fluid is a monomer, are used as pre-cursors. The monomer is preferentially located between the particles, creating capillary bridges, resulting in a strong, percolating network. Thermally induced polymerization of these bridges at temperatures below 100 °C for less than 5 hours and subsequent removal of the bulk fluid yields macroscopic, self-supporting solid bodies with high porosity. This process is demonstrated using methylmethacrylate and hydroxyethylmethacrlyate with glass particles as a model system. The produced PMMA had a molecular weight of about 500.000 g/mol and dispersity about three. Application specific porous bodies, including PMMA particles connected by PMMA bridges, micron-sized capsules containing phase change material with high inner surface, and porous graphite membranes with high electrical conductivity, are also shown.

  16. Alternative synthetic route for the heterometallic CO-releasing [Sb@Rh12(CO27]3− icosahedral carbonyl cluster and synthesis of its new unsaturated [Sb@Rh12(CO24]4− and dimeric [{Sb@Rh12Sb(CO25}2Rh(CO2PPh3]7− derivatives

    Directory of Open Access Journals (Sweden)

    Cristina Femoni

    2016-10-01

    Full Text Available The hetero-metallic [Sb@Rh12(CO27]3− cluster has been known as for over three decades thanks to Vidal and co-workers, and represents the first example of an E-centered (E=heteroatom icosahedral rhodium carbonyl cluster. However, its synthesis required high temperature (140–160 °C and elevated CO pressure (400 atm. Applying the redox condensation method for cluster preparation, we herein report a new synthetic, high-yield route for preparing [Sb@Rh12(CO27]3− under much milder conditions of temperature and pressure. Notably, when the same synthesis was carried out under N2 instead of CO atmosphere, the new isostructural but unsaturated derivative [Sb@Rh12(CO24]4− was obtained, for which we report the full X-ray structural characterization. This species represents one of the few examples of an icosahedral cluster disobeying the electron-counting Wade-Mingos rules, possessing less than the expected 170 cluster valence electrons (CVEs. Judging from IR monitoring, the two species can be obtained one from the other by switching between N2 and CO atmosphere, making [Sb@Rh12(CO27]3− a spontaneous CO-releasing molecule. Finally, the study of the chemical reactivity of [Sb@Rh12(CO27]3− with PPh3 allowed us to obtain the new [{Sb@Rh12Sb(CO25}2Rh(CO2PPh3]7− dimeric compound, for which we herein report the full X-ray structural and 31P NMR analyses.

  17. A novel low-temperature chemical solution route for straight and dendrite-like ZnO nanostructures

    International Nuclear Information System (INIS)

    Zhang Hui; Du Ning; Wu Jianbo; Ma, Xiangyang; Yang Deren; Zhang Xiaobin; Yang Zhiqing

    2007-01-01

    The straight and dendrite-like growths of ZnO have been completely and simply controlled by the status of ZnO seed instead of surfactant, template, oriented attachment, and ZnO buffer layer on the substrate in the chemical reaction synthesis of ZnO nanostructures. The monodisperse ZnO seeds, which are prepared by in situ quickly injecting the cool mixed zinc acetate and potassium hydrate ethanol solution into the hot matrix aqueous solution of zinc nitrate hydrate and diethylenetriamine at 95 deg. C, improve the straight growth and lots of uniform, straight, and single-crystalline ZnO nanorods with about 20-30 nm in diameter and 300 nm in length are achieved. While, the aggregated ZnO seeds, which are prepared by dropwise adding potassium hydrate ethanol solution into zinc acetate ethanol solution at 60 deg. C for 3 h, result in the dendrite-like growth and the bur-like ZnO nanostructures consisting of hundreds of nanorods with about 30-50 nm in diameter and several micrometers in length are formed. Furthermore, the approach presented here provides a simple, low-cost, environmental-friendly and high efficiency route to synthesize the high quality ZnO nanorods and bur-like ZnO nanostructures

  18. Aqueous chemical route synthesis and the effect of calcination temperature on the structural and optical properties of ZnO nanoparticles

    Directory of Open Access Journals (Sweden)

    Mohammad Ramzan Parra

    2014-10-01

    Full Text Available This article reports the controlled size of ZnO nanoparticles synthesized via simple aqueous chemical route without the involvement of any capping agent. The effect of different calcination temperatures on the size of the ZnO nanoparticles was investigated. X-ray diffraction (XRD results indicated that all the samples have crystalline wurtzite phase, and peak broadening analysis was used to evaluate the average crystallite size and lattice strain using Scherrer's equation and Williamson–Hall (W–H method. Morphology and elemental compositions were investigated using atomic force microscopy (AFM and scanning electron microscopy (SEM with energy-dispersive X-ray (EDX spectroscopy. The average crystallite size of ZnO nanoparticles estimated from Scherrer's formula and W–H analysis was found to increase with the increase in calcination temperature. These results were in good agreement with AFM results. Optical properties were investigated using UV–vis spectroscopy in diffused reflectance (DR mode, with a sharp increase in reflectivity at 375 nm and the material has a strong reflective characteristic after 420 nm at 500 °C calcination temperature. Furthermore, photoluminescence spectroscopic results revealed intensive ultraviolet (UV emission with reduced defect concentrations and a slight shifting in band gap energies with increased calcination temperature from 200 °C to 500 °C. This study suggests that the as-prepared ZnO nanoparticles with bandgap tunability might be utilized as window layer in optoelectronic devices.

  19. Solution-chemical route to generalized synthesis of metal germanate nanowires with room-temperature, light-driven hydrogenation activity of CO2 into renewable hydrocarbon fuels.

    Science.gov (United States)

    Liu, Qi; Zhou, Yong; Tu, Wenguang; Yan, Shicheng; Zou, Zhigang

    2014-01-06

    A facile solution-chemical route was developed for the generalized preparation of a family of highly uniform metal germanate nanowires on a large scale. This route is based on the use of hydrazine monohydrate/H2O as a mixed solvent under solvothermal conditions. Hydrazine has multiple effects on the generation of the nanowires: as an alkali solvent, a coordination agent, and crystal anisotropic growth director. Different-percentage cobalt-doped Cd2Ge2O6 nanowires were also successfully obtained through the addition of Co(OAc)2·4H2O to the initial reaction mixture for future investigation of the magnetic properties of these nanowires. The considerably negative conduction band level of the Cd2Ge2O6 nanowire offers a high driving force for photogenerated electron transfer to CO2 under UV-vis illumination, which facilitates CO2 photocatalytic reduction to a renewable hydrocarbon fuel in the presence of water vapor at room temperature.

  20. Synthetic routes to a nanoscale inorganic cluster [Ga{sub 13}(μ{sub 3}-OH){sub 6}(μ{sub 2}-OH){sub 18}(H{sub 2}O)](NO{sub 3}){sub 15} evaluated by solid-state {sup 71}Ga NMR

    Energy Technology Data Exchange (ETDEWEB)

    Hammann, Blake A. [Department of Chemistry, Washington University in St. Louis, St. Louis, MO 63130 (United States); Marsh, David A. [Department of Chemistry and Biochemistry, University of Oregon, Eugene, OR 97403 (United States); Ma, Zayd L. [Department of Chemistry, Washington University in St. Louis, St. Louis, MO 63130 (United States); Wood, Suzannah R. [Department of Chemistry and Biochemistry, University of Oregon, Eugene, OR 97403 (United States); Eric West, Michael [Department of Chemistry, Washington University in St. Louis, St. Louis, MO 63130 (United States); Johnson, Darren W. [Department of Chemistry and Biochemistry, University of Oregon, Eugene, OR 97403 (United States); Hayes, Sophia E., E-mail: hayes@wustl.edu [Department of Chemistry, Washington University in St. Louis, St. Louis, MO 63130 (United States)

    2016-10-15

    Solid-state {sup 71}Ga NMR was used to characterize a series of [Ga{sub 13}(μ{sub 3}-OH){sub 6}(μ{sub 2}-OH){sub 18}(H{sub 2}O)](NO{sub 3}){sub 15} “Ga{sub 13}” molecular clusters synthesized by multiple methods. These molecular clusters are precursors to thin film electronics and may be employed in energy applications. The synthetic routes provide varying levels of impurities in the solid phase, and these impurities often elude traditional characterization techniques such as powder X-ray diffraction and Raman spectroscopy. Solid-state NMR can provide a window into the gallium species even in amorphous phases. This information is vital in order to prevent the impurities from causing defect sites in the corresponding thin films upon gelation and condensation (polymerization) of the Ga{sub 13} clusters. This work demonstrates the resolving power of solid-state NMR to evaluate structure and synthetic quality in the solid state, and the application of high-field NMR to study quadrupolar species, such as {sup 71}Ga. - Graphical abstract: The various synthetic routes and {sup 71}Ga solid-state NMR spectra of the nanoscale inorganic cluster [Ga{sub 13}(μ{sub 3}-OH){sub 6}(μ{sub 2}-OH){sub 18}(H{sub 2}O)](NO{sub 3}){sub 15}. - Highlights: • Solid-state {sup 71}Ga NMR of hydroxo-aquo metal clusters and the impurities present. • High-field NMR capability allows for quadrupolar species, such as {sup 71}Ga, to be routinely studied. • Efficient and environmentally friendly synthetic routes have been developed to prepare hydroxo-aquo metal clusters.

  1. Development and characterization of high temperature, high energy density dielectric materials to establish routes towards power electronics capacitive devices

    Science.gov (United States)

    Shay, Dennis P.

    The maximum electrostatic energy density of a capacitor is a function of the relative permittivity (epsilonr) and the square of the dielectric breakdown strength (Eb). Currently, state-of-the art high temperature (>200 °C), SiC-based power electronics utilize CaZrO3-rich NP0/C0G-type capacitors, which have low relative permittivities of epsilonr ˜ 30-40, high breakdown strengths (> 1.0 MV/cm), and are chosen for their minimal change in energy storage with temperature. However, with operating temperatures exceeding the rated temperatures for such capacitors, there is an opportunity to develop new dielectric ceramics having higher energy densities and volumetric efficiencies at high temperatures (>200 °C) by utilizing higher permittivity dielectrics while maintaining high breakdown strengths via doping. The solid solution behavior of was characterized in order to determine the optimal composition for balancing permittivity and dielectric breakdown strength to obtain high energy densities at elevated temperatures. Characterization by X-ray diffraction (XRD) showed Vegard's law behavior across the solid solution with minimal 2nd phases. To determine a Ca(TixZr1-x)O3 composition that will also minimize electronic or band conduction, the optical properties of the Ca(TixZr1-x)O3 solid solution were investigated to identify a composition on the CaTiO3 - rich end of the solid solution with a large band gap. Both ultraviolet-visible diffuse reflectance spectroscopy (UV-Vis) and spectroscopic ellipsometry were utilized to determine the Ca(TixZr1-x)O3 band gaps and optical properties. The resistivity at 250 °C scaled with the band gap energy across the solid solution. Comparing the current-voltage (I--V) behavior at 250 °C for Ca(Tix-yMnyZr0.2)O3 (CTZ + Mn) where x = 0.7, 0.8, 0.9, and y = 0.005, it was found that the Ca(Ti 0.795Mn0.005Zr0.2)O3 composition showed the lowest current density and a decrease in current density of 5 orders of magnitude compared to the un

  2. Study on Temperature and Synthetic Compensation of Piezo-Resistive Differential Pressure Sensors by Coupled Simulated Annealing and Simplex Optimized Kernel Extreme Learning Machine.

    Science.gov (United States)

    Li, Ji; Hu, Guoqing; Zhou, Yonghong; Zou, Chong; Peng, Wei; Alam Sm, Jahangir

    2017-04-19

    As a high performance-cost ratio solution for differential pressure measurement, piezo-resistive differential pressure sensors are widely used in engineering processes. However, their performance is severely affected by the environmental temperature and the static pressure applied to them. In order to modify the non-linear measuring characteristics of the piezo-resistive differential pressure sensor, compensation actions should synthetically consider these two aspects. Advantages such as nonlinear approximation capability, highly desirable generalization ability and computational efficiency make the kernel extreme learning machine (KELM) a practical approach for this critical task. Since the KELM model is intrinsically sensitive to the regularization parameter and the kernel parameter, a searching scheme combining the coupled simulated annealing (CSA) algorithm and the Nelder-Mead simplex algorithm is adopted to find an optimal KLEM parameter set. A calibration experiment at different working pressure levels was conducted within the temperature range to assess the proposed method. In comparison with other compensation models such as the back-propagation neural network (BP), radius basis neural network (RBF), particle swarm optimization optimized support vector machine (PSO-SVM), particle swarm optimization optimized least squares support vector machine (PSO-LSSVM) and extreme learning machine (ELM), the compensation results show that the presented compensation algorithm exhibits a more satisfactory performance with respect to temperature compensation and synthetic compensation problems.

  3. Alternative route to metal halide free ionic liquids

    International Nuclear Information System (INIS)

    Takao, Koichiro; Ikeda, Yasuhisa

    2008-01-01

    An alternative synthetic route to metal halide free ionic liquids using trialkyloxonium salt is proposed. Utility of this synthetic route has been demonstrated by preparing 1-ethyl-3-methylimidazolium tetrafluoroborate ionic liquid through the reaction between 1-methylimidazole and triethyloxonium tetra-fluoroborate in anhydrous ether. (author)

  4. Shape- and size-controlled synthesis of nanometre ZnO from a simple solution route at room temperature

    International Nuclear Information System (INIS)

    Cao, H L; Qian, X F; Gong, Q; Du, W M; Ma, X D; Zhu, Z K

    2006-01-01

    Single crystalline ZnO nanorods with a diameter of about 5 nm were synthesized without the presence of any surfactants in ethanol solvent at room temperature. Nanodots and nanorods with different size and shape could be observed by TEM via simply altering NaOH concentration and reaction time. The polar ZnO nanorod growth mechanism was discussed by the 'Ostwald ripening' mechanism. Optical absorption and photoluminescence properties of ZnO nanorods have been characterized. The UV absorption spectrum revealed a clear blue-shift with a single absorption peak centred at 350 nm

  5. A self-propagation high-temperature synthesis and annealing route to synthesis of wave-like boron nitride nanotubes

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Jilin; Zhang, Laiping [School of Materials Science and Engineering, Wuhan Institute of Technology, Wuhan, Hubei, 430073 (China); Gu, Yunle, E-mail: ncm@mail.wit.edu.cn [School of Materials Science and Engineering, Wuhan Institute of Technology, Wuhan, Hubei, 430073 (China); Pan, Xinye; Zhao, Guowei; Zhang, Zhanhui [School of Materials Science and Engineering, Wuhan Institute of Technology, Wuhan, Hubei, 430073 (China)

    2013-03-15

    Highlights: ► Large quantities of wave-like BN nanotubes were synthesized by SHS-annealing method. ► The catalytic boron-containing porous precursor was produced by self-propagation high-temperature synthesis method. ► Three growth models were proposed to explain the growth mechanism of the wave-like BN nanotubes. - Abstract: Large quantities of boron nitride (BN) nanotubes were synthesized by annealing a catalytic boron-containing porous precursor in flowing NH{sub 3} gas at 1180 °C. The porous precursor was prepared by self-propagation high-temperature synthesis (SHS) method at 800 °C using Mg, B{sub 2}O{sub 3} and amorphous boron powder (α-B) as the starting materials. The porous precursor played an important role in large quantities synthesis of BN nanotubes. The as-synthesized product was characterized by X-ray diffractometer (XRD), Fourier transform infrared spectrometer (FTIR), Raman, Scanning electron microscopy (SEM), X-ray energy dispersive spectroscopy (EDS), Transmission electron microscopy (TEM) and High-resolution transmission electron microscopy (HRTEM). Characterization results indicated that the BN nanotubes displayed wave-like inner structures with diameters in the range of 50–300 nm and average lengths of more than 10 μm. The possible growth mechanism of the BN nanotubes was also discussed.

  6. Synthetic cold-inducible promoter enhances recombinant protein accumulation during Agrobacterium-mediated transient expression in Nicotiana excelsior at chilling temperatures.

    Science.gov (United States)

    Gerasymenko, I M; Sheludko, Y V

    2017-07-01

    To exploit cold-inducible biochemical processes beneficial for foreign mRNA transcription, translation and storage, as well as protein product stability, during Agrobacterium-mediated transient expression. The efficiency of three different 5'-regulatory sequences to achieve transient expression of the GFP-based reporter gene under chilling conditions (6-8 °C since the 3rd day post inoculation) was compared. We studied the upstream sequences of a cold-inducible Arabidopsis thaliana cor15a gene, the core element of 35S CaMV promoter fused to the TMV omega 5'-UTR, and the synthetic promoter including the 35S core sequence and two binding sites for cold-inducible CBF transcription factors (P_DRE::35S). Cultivation of plants transiently expressing reporter gene under control of the synthetic P_DRE::35S promoter under chilling conditions since the 3rd dpi led to the reliably higher reporter accumulation as compared to the other tested regulatory sequences under chilling or greenhouse conditions. Reporter protein fluorescence under chilling conditions using P_DRE::35S reached 160% as compared to the transient expression in the greenhouse. Period of transient expression considerably extended if plants were cultivated at chilling temperature since the 3rd dpi: reporter protein fluorescence reached its maximum at the 20th dpi and was detected in leaves up to the 65th dpi. The enhanced protein accumulation at low temperature was accompanied by the prolonged period of corresponding mRNA accumulation. Transient expression under chilling conditions using synthetic cold-inducible promoter enhances target protein accumulation and may decrease greenhouse heating expenses.

  7. Insights from Synthetic Star-forming Regions. II. Verifying Dust Surface Density, Dust Temperature, and Gas Mass Measurements With Modified Blackbody Fitting

    Energy Technology Data Exchange (ETDEWEB)

    Koepferl, Christine M.; Robitaille, Thomas P. [Max Planck Institute for Astronomy, Königstuhl 17, D-69117 Heidelberg (Germany); Dale, James E., E-mail: koepferl@usm.lmu.de [University Observatory Munich, Scheinerstr. 1, D-81679 Munich (Germany)

    2017-11-01

    We use a large data set of realistic synthetic observations (produced in Paper I of this series) to assess how observational techniques affect the measurement physical properties of star-forming regions. In this part of the series (Paper II), we explore the reliability of the measured total gas mass, dust surface density and dust temperature maps derived from modified blackbody fitting of synthetic Herschel observations. We find from our pixel-by-pixel analysis of the measured dust surface density and dust temperature a worrisome error spread especially close to star formation sites and low-density regions, where for those “contaminated” pixels the surface densities can be under/overestimated by up to three orders of magnitude. In light of this, we recommend to treat the pixel-based results from this technique with caution in regions with active star formation. In regions of high background typical in the inner Galactic plane, we are not able to recover reliable surface density maps of individual synthetic regions, since low-mass regions are lost in the far-infrared background. When measuring the total gas mass of regions in moderate background, we find that modified blackbody fitting works well (absolute error: + 9%; −13%) up to 10 kpc distance (errors increase with distance). Commonly, the initial images are convolved to the largest common beam-size, which smears contaminated pixels over large areas. The resulting information loss makes this commonly used technique less verifiable as now χ {sup 2} values cannot be used as a quality indicator of a fitted pixel. Our control measurements of the total gas mass (without the step of convolution to the largest common beam size) produce similar results (absolute error: +20%; −7%) while having much lower median errors especially for the high-mass stellar feedback phase. In upcoming papers (Paper III; Paper IV) of this series we test the reliability of measured star formation rate with direct and indirect

  8. The effect of synthetic method and annealing temperature on metal site preference in Al(1-x)Ga(x)FeO3.

    Science.gov (United States)

    Walker, James D S; Grosvenor, Andrew P

    2013-08-05

    Magnetoelectric materials couple both magnetic and electronic properties, making them attractive for use in multifunctional devices. The magnetoelectric AFeO3 compounds (Pna2(1); A = Al, Ga) have received attention as the properties of the system depend on composition as well as the synthetic method used. Al(1-x)Ga(x)FeO3. (0 ≤ x ≤ 1) was synthesized by the sol-gel and coprecipitation methods and studied by X-ray absorption near-edge spectroscopy (XANES). Al L(2,3-), Ga K-, and Fe K-edge XANES spectra were collected to examine how the average metal coordination number (CN) changes with the synthetic method. Al and Fe were found to prefer octahedral sites, while Ga prefers the tetrahedral site. It was found that composition played a larger role in determining site occupancies than synthetic method. Samples made by the sol-gel or ceramic methods (reported previously; Walker, J. D. S.; Grosvenor, A. P. J. Solid State Chem. 2013, 197, 147-153) showed smaller spectral changes than samples made via the coprecipitation method. This is attributed to greater ion mobility in samples synthesized via coprecipitation as the reactants do not have a long-range polymeric or oxide network during synthesis like samples synthesized via the sol-gel or ceramic method. Increasing annealing temperature increases the average coordination number of Al, and to a lesser extent Ga, while the average coordination number of Fe decreases. This study indicates that greater disorder is observed when the Al(1-x)Ga(x)FeO3. compounds have high Al content, and when annealed at higher temperatures.

  9. Insights from Synthetic Star-forming Regions. II. Verifying Dust Surface Density, Dust Temperature, and Gas Mass Measurements with Modified Blackbody Fitting

    Science.gov (United States)

    Koepferl, Christine M.; Robitaille, Thomas P.; Dale, James E.

    2017-11-01

    We use a large data set of realistic synthetic observations (produced in Paper I of this series) to assess how observational techniques affect the measurement physical properties of star-forming regions. In this part of the series (Paper II), we explore the reliability of the measured total gas mass, dust surface density and dust temperature maps derived from modified blackbody fitting of synthetic Herschel observations. We find from our pixel-by-pixel analysis of the measured dust surface density and dust temperature a worrisome error spread especially close to star formation sites and low-density regions, where for those “contaminated” pixels the surface densities can be under/overestimated by up to three orders of magnitude. In light of this, we recommend to treat the pixel-based results from this technique with caution in regions with active star formation. In regions of high background typical in the inner Galactic plane, we are not able to recover reliable surface density maps of individual synthetic regions, since low-mass regions are lost in the far-infrared background. When measuring the total gas mass of regions in moderate background, we find that modified blackbody fitting works well (absolute error: + 9%; -13%) up to 10 kpc distance (errors increase with distance). Commonly, the initial images are convolved to the largest common beam-size, which smears contaminated pixels over large areas. The resulting information loss makes this commonly used technique less verifiable as now χ 2 values cannot be used as a quality indicator of a fitted pixel. Our control measurements of the total gas mass (without the step of convolution to the largest common beam size) produce similar results (absolute error: +20%; -7%) while having much lower median errors especially for the high-mass stellar feedback phase. In upcoming papers (Paper III; Paper IV) of this series we test the reliability of measured star formation rate with direct and indirect techniques.

  10. Room temperature synthesis and characterization of ultralong Cd(OH)2 nanowires: a simple and template-free chemical route

    International Nuclear Information System (INIS)

    Sahraei, R.; Daneshfar, A.; Roushani, M.; Mihandoost, A.; Nabiyouni, G.; Majles Ara, M.H.

    2012-01-01

    Ultralong Cd(OH) 2 nanowires were fabricated in high yield by a convenient chemical method using alkali medium at room temperature without using any templates. The preparation conditions induce a unilateral growth of nanowires, despite the absence of any template. The length of the nanowires reached several hundreds of micrometers, giving an aspect ratio of a few thousands. The X-ray diffraction shows that the Cd(OH) 2 nanostructures crystallized in the wurtzite structure without any special orientation. The photoluminescence spectrum of Cd(OH) 2 nanostructures appears as two emission bands: one related to green emission at 475-510 nm, and the other related to deep level emission at 510-540 nm. Also the formation mechanisms of the nanowires are presented. The growth mechanism involves the irreversible and specifically oriented self-assembly of primary nanocrystals and results in the formation of the nanowires. (orig.)

  11. A novel one-pot room-temperature synthesis route to produce very small photoluminescent silicon nanocrystals

    Science.gov (United States)

    Douglas-Gallardo, Oscar A.; Burgos-Paci, Maxi A.; Mendoza-Cruz, Rubén; Putnam, Karl G.; Josefina Arellano-Jiménez, M.; José-Yacamán, Miguel; Mariscal, Marcelo M.; Macagno, Vicente A.; Sánchez, Cristián G.; Pérez, Manuel A.

    2018-03-01

    A novel strategy to synthesize photoluminescent silicon nanocrystals (SiNCs) from a reaction between tetraethylorthosilicate (TEOS) and trimethyl-hexadecyl-ammonium borohydride (CTABH4) in organic solvent is presented. The formation reaction occurs spontaneously at room temperature in homogeneous phase. The produced silicon nanocrystals are characterized by using their photoluminescent properties and via HRTEM. In addition, theoretical calculations of the optical absorption spectrum of silicon quantum dots in vacuum with different sizes and surface moieties were performed in order to compare with the experimental findings. The new chemical reaction is simple and can be implemented to produce silicon nanocrystal with regular laboratory materials by performing easy and safe procedures. [Figure not available: see fulltext.

  12. Surfactant controlled low-temperature thermal decomposition route to zinc oxide nanorods from zinc(II) acetylacetonate monohydrate

    Energy Technology Data Exchange (ETDEWEB)

    Purkayastha, Debraj Dhar; Sarma, Bedabrat; Bhattacharjee, Chira R., E-mail: crbhattacharjee@rediffmail.com

    2014-10-15

    Zinc oxide (ZnO) nanorods were synthesized via a low-temperature thermal decomposition of zinc(II) acetylacetonate monohydrate, [Zn(C{sub 5}H{sub 7}O{sub 2}){sub 2}].H{sub 2}O. A relatively inexpensive surfactant, octadecylamine (C{sub 18}H{sub 37}NH{sub 2}) served both as a reaction solvent and a capping agent during the synthesis of ZnO nanorods. The synthesized nanorods were characterized by powder X-ray diffraction (XRD), transmission electron microscopy (TEM), FT-IR, UV–visible, and photoluminescence (PL) studies. The XRD spectrum furnished evidence for the hexagonal wurtzite structure of ZnO. TEM images revealed the material to be rod shaped having diameter 30 nm and length 200 nm. The HRTEM image showed that the lattice fringes between the two adjacent planes are 0.244 nm apart, which corresponds to the interplanar separation of the (1 0 1) plane of hexagonal ZnO. The electron diffraction (ED) pattern confirmed the single crystalline nature of the nanorods. The PL spectrum showed two UV emissions at 356 nm (∼3.48 eV) and 382 nm (∼3.25 eV). ZnO nanorods also showed very weak blue bands at 445, 453 and 470 nm. - Highlights: Low temperature thermal decomposition of zinc(II) acetylacetonate monohydrate gave zinc oxide nanorods. Powder XRD showed hexagonal wurtzite structure of ZnO having average diameter about 24 nm. TEM images revealed the material to be of rod shape having diameter 30 nm and length 200 nm. ZnO showed band gap luminescence at 356 nm, excitonic emission at 382 nm and defect related blue bands. The synthesis is simple and can act as a paradigm for obtaining various metal oxide nanomaterials.

  13. Thermodynamic Analysis of Ionic Compounds: Synthetic Applications.

    Science.gov (United States)

    Yoder, Claude H.

    1986-01-01

    Shows how thermodynamic cycles can be used to understand trends in heats of formation and aqueous solubilities and, most importantly, how they may be used to choose synthetic routes to new ionic compounds. (JN)

  14. Comparison of Reactive and Non-Reactive Spark Plasma Sintering Routes for the Fabrication of Monolithic and Composite Ultra High Temperature Ceramics (UHTC Materials

    Directory of Open Access Journals (Sweden)

    Roberto Orrù

    2013-04-01

    Full Text Available A wider utilization of ultra high temperature ceramics (UHTC materials strongly depends on the availability of efficient techniques for their fabrication as dense bodies. Based on recent results reported in the literature, it is possible to state that Spark Plasma Sintering (SPS technology offers a useful contribution in this direction. Along these lines, the use of two different SPS-based processing routes for the preparation of massive UHTCs is examined in this work. One method, the so-called reactive SPS (R-SPS, consists of the synthesis and densification of the material in a single step. Alternatively, the ceramic powders are first synthesized by Self-propagating High-temperature Synthesis (SHS and then sintered by SPS. The obtained results evidenced that R-SPS method is preferable for the preparation of dense monolithic products, while the sintering of SHS powders requires relatively milder conditions when considering binary composites. The different kinetic mechanisms involved during R-SPS of the monolithic and composite systems, i.e., combustion-like or gradual solid-diffusion, respectively, provides a possible explanation. An important role is also played by the SHS process, particularly for the preparation of composite powders, since stronger interfaces are established between the ceramic constituents formed in situ, thus favoring diffusion processes during the subsequent SPS step.

  15. Uniform β-Co(OH)2 disc-like nanostructures prepared by low-temperature electrochemical rout as an electrode material for supercapacitors

    Science.gov (United States)

    Aghazadeh, Mustafa; Shiri, Hamid Mohammad; Barmi, Abbas-Ali Malek

    2013-05-01

    Uniform nanostructures of cobalt hydroxide were successfully prepared by a low-temperature electrochemical method via galvanostatically deposition from a 0.005 M Co(NO3)3 bath at 10 °C. The XRD and FT-IR analyses showed that the prepared sample has a single crystalline hexagonal phase of the brucite-like Co(OH)2. Morphological characterization by SEM and TEM revealed that the prepared β-Co(OH)2 was composed of uniform compact disc-like nanostructures with diameters of 40-50 nm. The electrochemical performance of the prepared β-Co(OH)2 was evaluated using cyclic voltammetry and charge-discharge tests. A maximum specific capacitance of 736.5 F g-1 was obtained in aqueous 1 M KOH with the potential range of -0.2-0.5 V (vs. Ag/AgCl) at the scan rate of 10 mV s-1, suggesting the potential application of the prepared nanostructures as an electrode material in electrochemical supercapacitors. The results of this work showed that the low-temperature cathodic electrodeposition method can be recognized as a new and facile route for the synthesis of cobalt hydroxide nanodiscs as a promising candidate for the electrochemical supercapacitors.

  16. Effects of Cr-doping on the photoluminescence and ferromagnetism at room temperature in ZnO nanomaterials prepared by soft chemistry route

    International Nuclear Information System (INIS)

    Wang Baiqi; Iqbal, Javed; Shan Xudong; Huang Guowei; Fu Honggang; Yu Ronghai; Yu Dapeng

    2009-01-01

    The pure and Cr-doped ZnO nanomaterials were prepared by soft chemistry route. The crystallinity and morphology of as-prepared ZnO nanomaterials were studied by X-ray diffraction (XRD), transmission electron microscopy (TEM) and high-resolution transmission electron microscopy (HRTEM), which show that Cr-doping could influence crystal and improve the oriented growth of ZnO nanomaterials. The amount of contents and valence state of Cr ions were investigated by energy dispersive spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS), which demonstrate that the Cr ions are uniformly doped about 2 atm% in each nanowire and are in +3 valence state in doped ZnO nanomaterials. The effect of Cr-doping on the photoluminescence (PL) and magnetic properties of as-prepared ZnO nanomaterials were principally investigated at room temperature. The Cr-doping can adjust the energy level of ZnO nanocrystal and increase the amount of defects and oxygen vacancies, which lead to shift in the emission peak position in ultraviolet (UV) region and enhance the PL performance in visible light (VL) region of ZnO nanomaterials. In addition, the presence of Cr dopant in ZnO structures establishes the room-temperature ferromagnetism, which is possibly related to the existence of defects and oxygen vacancies as well as due to exchange interaction between Cr 3d and O 2p spin moments

  17. Mg(OH){sub 2} nanoparticles produced at room temperature by an innovative, facile, and scalable synthesis route

    Energy Technology Data Exchange (ETDEWEB)

    Taglieri, Giuliana, E-mail: giuliana.taglieri@univaq.it; Felice, Benito; Daniele, Valeria; Ferrante, Fabiola [University of L’Aquila, Department of Industrial and Information Engineering and Economics (Italy)

    2015-10-15

    Nanoparticles form the fundamental building blocks for many exciting applications in various scientific disciplines. However, the problem of the large-scale synthesis of nanoparticles remains challenging. An original, eco-friendly, single step, and scalable method to produce magnesium hydroxide nanoparticles in aqueous suspensions is here presented. The method, based on an exchange ion process, is extremely simple and rapid (few minutes). It employs cheap or renewable reactants, operates at room temperature and does not require intermediate steps (washings/purifications) to eliminate undesired compounds. Moreover, it is possible to regenerate the exchange material and to reuse it for new operation of synthesis, according to a cyclic procedure, providing potential aptitudes of scalability of nanoparticles production. Some of the synthesis parameters are varied, and structural and morphological features of the produced nanoparticles, after few seconds from the beginning of the synthesis up to the ending time, are investigated by means of several techniques, such as X-ray diffraction (profile fitting and Rietveld refinement), transmission electron microscopy, infrared spectroscopy, thermal analyses, and surface area measurements. In any case, pure and stable suspensions are produced, characterized by crystalline and mesoporous Mg(OH){sub 2} nanoparticles, with lamellar morphology. In particular, the nanolamellas appeared constituted by a superimposition of hexagonally plated and crystalline nanosized precursors (2–3 nm in dimensions), crystallographically oriented.

  18. A low temperature situ precipitation route to designing Zn-doped SnO2 photocatalyst with enhanced photocatalytic performance

    International Nuclear Information System (INIS)

    Jia, Xiaohua; Liu, Yingying; Wu, Xiangyang; Zhang, Zhen

    2014-01-01

    Highlights: • A new Zn doped SnO 2 photocatalyst was successfully achieved and characterized. • The Zn doped SnO 2 photocatalyst exhibited excellent photocatalytic activity and stability for the photodegradation RhB. • Photocatalytic mechanisms both under visible and UV–vis light irradiation were proposed. - Abstract: Zn doped SnO 2 nanoparticles have been fabricated through the low temperature situ precipitation technique. The morphology, structure and chemical composition of the nanoparticles are characterized using field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), UV–vis diffuse reflectance spectroscopy (DRS), Thermogravimetric-differential scanning calorimetry (TG–DSC) and UV–vis absorption spectroscopy. The products were also characterized by X-ray diffraction (XRD) and X-photoelectron spectrum (XPS), and the results indicated that Sn 4+ ions were successfully substituted by Zn 2+ . Their photocatalytic activities were evaluated using rhodamine B (RhB) as a decomposition objective. The results show that the Zn doped SnO 2 display higher photocatalytic activities in the degradation of RhB than pure ZnO products by exposure to UV irradiation. A possible reason of the increased photocatalytic activity of Zn doped SnO 2 is attributed to intrinsic oxygen vacancies in nanoparticles and extrinsic defect due to Zn hole doping

  19. A rapid biosynthesis route for the preparation of gold nanoparticles by aqueous extract of cypress leaves at room temperature

    Science.gov (United States)

    Noruzi, Masumeh; Zare, Davood; Davoodi, Daryoush

    In the present study, green synthesis of gold nanoparticles was reported using the aqueous extract of cypress leaves. The reduction of gold salt with the extract of cypress leaves resulted in the formation of gold nanoparticles. Effects of extract concentration and extract pH were investigated on the size of the nanoparticles. It was found that the average particle size of synthesized gold nanoparticles depends strongly on extract concentration and extract pH. FT-IR spectroscopy showed that bioorganic capping molecules were bound to the surface of particles. X-ray techniques confirmed the formation of gold nanoparticles and their crystalline structure. The inductively coupled plasma atomic emission spectroscopy analysis displayed that the reaction progress is higher than 90% at room temperature. Gold nanoparticles were mostly spherical in shape along with some irregular shapes. Cypress is an evergreen plant and its leaves are easily available in all four seasons. Also, the rate of the reaction was high and it was completed in only 10 min. For these reasons, this method is cost-effective and environmentally friendly. Thus, it can be used in the synthesis of gold nanoparticles instead of chemical methods and other biosynthesis approaches.

  20. LOW TEMPERATURE FORMATION OF NITROGEN-SUBSTITUTED POLYCYCLIC AROMATIC HYDROCARBONS (PANHs)—BARRIERLESS ROUTES TO DIHYDRO(iso)QUINOLINES

    Energy Technology Data Exchange (ETDEWEB)

    Parker, Dorian S. N.; Yang, Tao; Dangi, Beni B.; Kaiser, Ralf I. [Department of Chemistry, University of Hawaii at Manoa, Honolulu, HI 96822 (United States); Bera, Partha P.; Lee, Timothy J., E-mail: ralfk@hawaii.edu, E-mail: Timothy.J.Lee@nasa.gov [Space Science and Astrobiology Division, NASA Ames Research Center, Moffett Field, Mountain View, CA 94035 (United States)

    2015-12-20

    Meteorites contain bio-relevant molecules such as vitamins and nucleobases, which consist of aromatic structures with embedded nitrogen atoms. Questions remain over the chemical mechanisms responsible for the formation of nitrogen-substituted polycyclic aromatic hydrocarbons (PANHs) in extraterrestrial environments. By exploiting single collision conditions, we show that a radical mediated bimolecular collision between pyridyl radicals and 1,3-butadiene in the gas phase forms nitrogen-substituted polycyclic aromatic hydrocarbons (PANHs) 1,4-dihydroquinoline and to a minor amount 1,4-dihydroisoquinoline. The reaction proceeds through the formation of a van der Waals complex, which circumnavigates the entrance barrier implying it can operate at very low kinetic energy and therefore at low temperatures of 10 K as present in cold molecular clouds such as TMC-1. The discovery of facile de facto barrierless exoergic reaction mechanisms leading to PANH formation could play an important role in providing a population of aromatic structures upon which further photo-processing of ice condensates could occur to form nucleobases.

  1. Alternate applications of fusion power: development of a high-temperature blanket for synthetic-fuel production

    International Nuclear Information System (INIS)

    Howard, P.A.; Mattas, R.F.; Krajcinovic, D.; DePaz, J.; Gohar, Y.

    1981-11-01

    This study has shown that utilization of the unique features of a fusion reactor can result in a novel and potentially economical method of decomposing steam into hydrogen and oxygen. Most of the power of fusion reactors is in the form of energetic neutrons. If this power could be used to produce high temperature uncontaminated steam, a large fraction of the energy needed to decomposee the steam could be supplied as thermal energy by the fusion reaction. Proposed high temperature electrolysis processes require steam temperature in excess of 1000 0 C for high efficiency. The design put forth in this study details a system that can accomplish that end

  2. Synthetic Cannabinoids

    Directory of Open Access Journals (Sweden)

    Aslihan Okan Ibiloglu

    2017-09-01

    Full Text Available Synthetic cannabinoids which is a subgroup of cannabinoids are commonly used for recreational drug use throughout the whole world. Although both marijuana and synthetic cannabinoids stimulate the same receptors, cannabinoid receptor 1 (CB1 and cannabinoid receptor 2 (CB2, studies have shown that synthetic cannabinoids are much more potent than marijuana. The longer use of synthetic cannabinoids can cause severe physical and psychological symptoms that might even result in death, similar to many known illicit drugs. Main treatment options mostly involve symptom management and supportive care. The aim of this article is to discuss clinical and pharmacological properties of the increasingly used synthetic cannabinoids. [Psikiyatride Guncel Yaklasimlar - Current Approaches in Psychiatry 2017; 9(3.000: 317-328

  3. New Hybrid Route to Biomimetic Synthesis

    National Research Council Canada - National Science Library

    Morse, Daniel

    2003-01-01

    To develop economical low-temperature routes to biomimetic synthesis of high-performance composite materials, with control of composition and structure based on the molecular mechanisms controlling...

  4. Cell formation effects on the burning speeds and flame front area of synthetic gas at high pressures and temperatures

    International Nuclear Information System (INIS)

    Askari, Omid; Elia, Mimmo; Ferrari, Matthew; Metghalchi, Hameed

    2017-01-01

    Highlights: • Effect of cell formation on burning speed and flame surface area is investigated. • A new developed non-dimensional number called cellularity factor is introduced. • Cellular burning speed and mass burning rate are calculated using differential based multi-shell model. • Flame instability is studied using thermo-diffusive and hydrodynamics effects. • Power law correlations are developed for cellular burning speeds and mass burning rates. - Abstract: Cellular burning speeds and mass burning rates of premixed syngas/oxidizer/diluent (H_2/CO/O_2/He) have been determined at high pressures and temperatures over a wide range of equivalence ratios which are at engine-relevant conditions. Working on high pressure combustion helps to reduce the pollution and increase the energy efficiency in combustion devices. The experimental facilities consisted of two spherical and cylindrical chambers. The spherical chamber, which can withstand high pressures up to 400 atm, was used to collect pressure rise data due to combustion, to calculate cellular burning speed and mass burning rate. For flame structure and instability analysis the cylindrical chamber was used to take pictures of propagating flame using a high speed CMOS camera and a schlieren photography system. A new differential based multi-shell model based on pressure rise data was used to determine the cellular burning speed and mass burning rate. In this paper, cellular burning speed and mass burning rate of H_2/CO/O_2/He mixture have been measured for a wide range of equivalence ratios from 0.6 to 2, temperatures from 400 to 750 K and pressures from 2 to 50 atm for three hydrogen concentrations of 5, 10 and 25% in the syngas. The power law correlations for cellular burning speed and mass burning rate were developed as a function of equivalence ratio, temperature and pressure. In this study a new developed parameter, called cellularity factor, which indicates the cell formation effect on flame

  5. Stacking Defects in Synthetic and Meteoritic Hibonites: Implications for High-Temperature Processes in the Solar Nebula

    Science.gov (United States)

    Han, J.; Keller, L. P.; Brearley, A. J.; Danielson, L. R.

    2016-01-01

    Hibonite (CaAl12O19) is a primary, highly refractory phase occurring in many Ca-Al-rich inclusions (CAIs) from different chondrite groups, except CI chondrites. Hibonite is predicted to be one of the earliest minerals to condense during cooling of the solar nebula at higher temperatures than any other major CAI mineral. Therefore, hibonite has great potential to reveal the processes and conditions of the very early, high-temperature stages of the solar nebular evolution. Previous microstructural studies of hibonite in CAIs and their Wark-Lovering (WL) rims showed the presence of numerous stacking defects in hibonite. These defects are interpreted as the modification of the stacking sequences of spinel and Ca-containing blocks within the ideal hexagonal hibonite structure, as shown by experimental studies of reaction-sintered ceramic CaO-Al2O3 compounds. We performed preliminary experiments in the CaO-Al2O3-MgO system to understand the formation processes and conditions of defect-structured hibonite found in meteorites.

  6. Cationic Pd(II-catalyzed C–H activation/cross-coupling reactions at room temperature: synthetic and mechanistic studies

    Directory of Open Access Journals (Sweden)

    Takashi Nishikata

    2016-05-01

    Full Text Available Cationic palladium(II complexes have been found to be highly reactive towards aromatic C–H activation of arylureas at room temperature. A commercially available catalyst [Pd(MeCN4](BF42 or a nitrile-free cationic palladium(II complex generated in situ from the reaction of Pd(OAc2 and HBF4, effectively catalyzes C–H activation/cross-coupling reactions between aryl iodides, arylboronic acids and acrylates under milder conditions than those previously reported. The nature of the directing group was found to be critical for achieving room temperature conditions, with the urea moiety the most effective in promoting facile coupling reactions at an ortho C–H position. This methodology has been utilized in a streamlined and efficient synthesis of boscalid, an agent produced on the kiloton scale annually and used to control a range of plant pathogens in broadacre and horticultural crops. Mechanistic investigations led to a proposed catalytic cycle involving three steps: (1 C–H activation to generate a cationic palladacycle; (2 reaction of the cationic palladacycle with an aryl iodide, arylboronic acid or acrylate, and (3 regeneration of the active cationic palladium catalyst. The reaction between a cationic palladium(II complex and arylurea allowed the formation and isolation of the corresponding palladacycle intermediate, characterized by X-ray analysis. Roles of various additives in the stepwise process have also been studied.

  7. Synthetic biology and metabolic engineering.

    Science.gov (United States)

    Stephanopoulos, Gregory

    2012-11-16

    Metabolic engineering emerged 20 years ago as the discipline occupied with the directed modification of metabolic pathways for the microbial synthesis of various products. As such, it deals with the engineering (design, construction, and optimization) of native as well as non-natural routes of product synthesis, aided in this task by the availability of synthetic DNA, the core enabling technology of synthetic biology. The two fields, however, only partially overlap in their interest in pathway engineering. While fabrication of biobricks, synthetic cells, genetic circuits, and nonlinear cell dynamics, along with pathway engineering, have occupied researchers in the field of synthetic biology, the sum total of these areas does not constitute a coherent definition of synthetic biology with a distinct intellectual foundation and well-defined areas of application. This paper reviews the origins of the two fields and advances two distinct paradigms for each of them: that of unit operations for metabolic engineering and electronic circuits for synthetic biology. In this context, metabolic engineering is about engineering cell factories for the biological manufacturing of chemical and pharmaceutical products, whereas the main focus of synthetic biology is fundamental biological research facilitated by the use of synthetic DNA and genetic circuits.

  8. Facile synthesis of both needle-like and spherical hydroxyapatite nanoparticles: effect of synthetic temperature and calcination on morphology, crystallite size and crystallinity.

    Science.gov (United States)

    Wijesinghe, W P S L; Mantilaka, M M M G P G; Premalal, E V A; Herath, H M T U; Mahalingam, S; Edirisinghe, M; Rajapakse, R P V J; Rajapakse, R M G

    2014-09-01

    Synthetic hydroxyapatite (HA) nanoparticles, that mimic natural HA, are widely used as biocompatible coatings on prostheses to repair and substitute human bones. In this study, HA nanoparticles are prepared by precipitating them from a precursor solution containing calcium sucrate and ammonium dihydrogen orthophosphate, at a Ca/P mole ratio of 1.67:1, at temperatures, ranging from 10°C to 95°C. A set of products, prepared at different temperatures, is analyzed for their crystallinity, crystallite size, morphology, thermal stability and composition, by X-ray diffraction (XRD), scanning electron microscopy (SEM), thermogravimetric analysis (TGA) and Fourier transform infrared (FT-IR) spectroscopic techniques, while the other set is analyzed after calcining the respective products, soon after their synthesis, for 3h, at 700°C. The as-prepared products, after 2h of drying, without any calcination, are not crystalline, but they grow very slowly into needle-like morphologies, as they are ripened with time. The percentage crystallinity of the final products increases from 15% to 52%, with increasing the preparative temperature. The calcined samples always produce spherical nanoparticles of essentially the same diameter, between 90 nm and 100 nm, which does not change due to aging and preparative temperatures. Therefore, the same method can be utilized to synthesize both spherical and needle-like nanoparticles of hydroxyapatite, with well-defined sizes and shapes. The ability to use readily available cheap raw materials, for the synthesis of such well-defined crystallites of hydroxyapatite, is an added advantage of this method, which may be explored further for the scaling up of the procedures to suit to industrial scale synthesis of such hydroxyapatite nanoparticles. Copyright © 2014 Elsevier B.V. All rights reserved.

  9. Facile synthesis of both needle-like and spherical hydroxyapatite nanoparticles: Effect of synthetic temperature and calcination on morphology, crystallite size and crystallinity

    International Nuclear Information System (INIS)

    Wijesinghe, W.P.S.L.; Mantilaka, M.M.M.G.P.G.; Premalal, E.V.A.; Herath, H.M.T.U.; Mahalingam, S.; Edirisinghe, M.; Rajapakse, R.P.V.J.; Rajapakse, R.M.G.

    2014-01-01

    Synthetic hydroxyapatite (HA) nanoparticles, that mimic natural HA, are widely used as biocompatible coatings on prostheses to repair and substitute human bones. In this study, HA nanoparticles are prepared by precipitating them from a precursor solution containing calcium sucrate and ammonium dihydrogen orthophosphate, at a Ca/P mole ratio of 1.67:1, at temperatures, ranging from 10 °C to 95 °C. A set of products, prepared at different temperatures, is analyzed for their crystallinity, crystallite size, morphology, thermal stability and composition, by X-ray diffraction (XRD), scanning electron microscopy (SEM), thermogravimetric analysis (TGA) and Fourier transform infrared (FT-IR) spectroscopic techniques, while the other set is analyzed after calcining the respective products, soon after their synthesis, for 3 h, at 700 °C. The as-prepared products, after 2 h of drying, without any calcination, are not crystalline, but they grow very slowly into needle-like morphologies, as they are ripened with time. The percentage crystallinity of the final products increases from 15% to 52%, with increasing the preparative temperature. The calcined samples always produce spherical nanoparticles of essentially the same diameter, between 90 nm and 100 nm, which does not change due to aging and preparative temperatures. Therefore, the same method can be utilized to synthesize both spherical and needle-like nanoparticles of hydroxyapatite, with well-defined sizes and shapes. The ability to use readily available cheap raw materials, for the synthesis of such well-defined crystallites of hydroxyapatite, is an added advantage of this method, which may be explored further for the scaling up of the procedures to suit to industrial scale synthesis of such hydroxyapatite nanoparticles. - Highlights: • Hydroxyapatite nanoparticles are synthesized using a simple precipitation method. • Both needle-like and spherical hydroxyapatite nanoparticles are synthesized. • The prepared

  10. Facile synthesis of both needle-like and spherical hydroxyapatite nanoparticles: Effect of synthetic temperature and calcination on morphology, crystallite size and crystallinity

    Energy Technology Data Exchange (ETDEWEB)

    Wijesinghe, W.P.S.L.; Mantilaka, M.M.M.G.P.G. [Department of Chemistry, Faculty of Science, University of Peradeniya, Peradeniya 20400 (Sri Lanka); Post-graduate Institute of Science, P.O. Box: 25, University of Peradeniya, Peradeniya 20400 (Sri Lanka); Premalal, E.V.A. [Department of Materials Science, Shizuoka University, Johoku, Naka-ku Hamamatsu, 432-8011 (Japan); Herath, H.M.T.U. [Department of Medical Laboratory Science, Faculty of Allied Health Sciences, University of Peradeniya, Peradeniya 20400 (Sri Lanka); Mahalingam, S.; Edirisinghe, M. [Department of Mechanical Engineering, University College London, London WC1E 7JE (United Kingdom); Rajapakse, R.P.V.J. [Department of Veterinary Pathobiology, Faculty of Veterinary, University of Peradeniya, Peradeniya 20400 (Sri Lanka); Rajapakse, R.M.G., E-mail: rmgr@pdn.ac.lk [Department of Chemistry, Faculty of Science, University of Peradeniya, Peradeniya 20400 (Sri Lanka); Post-graduate Institute of Science, P.O. Box: 25, University of Peradeniya, Peradeniya 20400 (Sri Lanka)

    2014-09-01

    Synthetic hydroxyapatite (HA) nanoparticles, that mimic natural HA, are widely used as biocompatible coatings on prostheses to repair and substitute human bones. In this study, HA nanoparticles are prepared by precipitating them from a precursor solution containing calcium sucrate and ammonium dihydrogen orthophosphate, at a Ca/P mole ratio of 1.67:1, at temperatures, ranging from 10 °C to 95 °C. A set of products, prepared at different temperatures, is analyzed for their crystallinity, crystallite size, morphology, thermal stability and composition, by X-ray diffraction (XRD), scanning electron microscopy (SEM), thermogravimetric analysis (TGA) and Fourier transform infrared (FT-IR) spectroscopic techniques, while the other set is analyzed after calcining the respective products, soon after their synthesis, for 3 h, at 700 °C. The as-prepared products, after 2 h of drying, without any calcination, are not crystalline, but they grow very slowly into needle-like morphologies, as they are ripened with time. The percentage crystallinity of the final products increases from 15% to 52%, with increasing the preparative temperature. The calcined samples always produce spherical nanoparticles of essentially the same diameter, between 90 nm and 100 nm, which does not change due to aging and preparative temperatures. Therefore, the same method can be utilized to synthesize both spherical and needle-like nanoparticles of hydroxyapatite, with well-defined sizes and shapes. The ability to use readily available cheap raw materials, for the synthesis of such well-defined crystallites of hydroxyapatite, is an added advantage of this method, which may be explored further for the scaling up of the procedures to suit to industrial scale synthesis of such hydroxyapatite nanoparticles. - Highlights: • Hydroxyapatite nanoparticles are synthesized using a simple precipitation method. • Both needle-like and spherical hydroxyapatite nanoparticles are synthesized. • The prepared

  11. Time-dependent analysis of visible helium line-ratios for electron temperature and density diagnostic using synthetic simulations on NSTX-U

    Energy Technology Data Exchange (ETDEWEB)

    Muñoz Burgos, J. M., E-mail: jmunozbu@pppl.gov; Stutman, D.; Tritz, K. [Department of Physics and Astronomy, Johns Hopkins University, Baltimore, Maryland 21218 (United States); Barbui, T.; Schmitz, O. [Department of Engineering Physics, University of Wisconsin-Madison, Madison, Wisconsin 53706 (United States)

    2016-11-15

    Helium line-ratios for electron temperature (T{sub e}) and density (n{sub e}) plasma diagnostic in the Scrape-Off-Layer (SOL) and edge regions of tokamaks are widely used. Due to their intensities and proximity of wavelengths, the singlet, 667.8 and 728.1 nm, and triplet, 706.5 nm, visible lines have been typically preferred. Time-dependency of the triplet line (706.5 nm) has been previously analyzed in detail by including transient effects on line-ratios during gas-puff diagnostic applications. In this work, several line-ratio combinations within each of the two spin systems are analyzed with the purpose of eliminating transient effects to extend the application of this powerful diagnostic to high temporal resolution characterization of plasmas. The analysis is done using synthetic emission modeling and diagnostic for low electron density NSTX SOL plasma conditions by several visible lines. Quasi-static equilibrium and time-dependent models are employed to evaluate transient effects of the atomic population levels that may affect the derived electron temperatures and densities as the helium gas-puff penetrates the plasma. The analysis of a wider range of spectral lines will help to extend this powerful diagnostic to experiments where the wavelength range of the measured spectra may be constrained either by limitations of the spectrometer or by other conflicting lines from different ions.

  12. Synthetic environments

    Science.gov (United States)

    Lukes, George E.; Cain, Joel M.

    1996-02-01

    The Advanced Distributed Simulation (ADS) Synthetic Environments Program seeks to create robust virtual worlds from operational terrain and environmental data sources of sufficient fidelity and currency to interact with the real world. While some applications can be met by direct exploitation of standard digital terrain data, more demanding applications -- particularly those support operations 'close to the ground' -- are well-served by emerging capabilities for 'value-adding' by the user working with controlled imagery. For users to rigorously refine and exploit controlled imagery within functionally different workstations they must have a shared framework to allow interoperability within and between these environments in terms of passing image and object coordinates and other information using a variety of validated sensor models. The Synthetic Environments Program is now being expanded to address rapid construction of virtual worlds with research initiatives in digital mapping, softcopy workstations, and cartographic image understanding. The Synthetic Environments Program is also participating in a joint initiative for a sensor model applications programer's interface (API) to ensure that a common controlled imagery exploitation framework is available to all researchers, developers and users. This presentation provides an introduction to ADS and the associated requirements for synthetic environments to support synthetic theaters of war. It provides a technical rationale for exploring applications of image understanding technology to automated cartography in support of ADS and related programs benefitting from automated analysis of mapping, earth resources and reconnaissance imagery. And it provides an overview and status of the joint initiative for a sensor model API.

  13. Hurricane Evacuation Routes

    Data.gov (United States)

    Department of Homeland Security — Hurricane Evacuation Routes in the United States A hurricane evacuation route is a designated route used to direct traffic inland in case of a hurricane threat. This...

  14. Synthetic Rutile

    International Nuclear Information System (INIS)

    Burastero, J.

    1975-01-01

    This work is about the laboratory scale investigation of the conditions in the rutile synthetic production from one me nita in Aguas Dulces reservoir. The iron mineral is chlorinated and volatilized selectively leaving a residue enriched in titanium dioxide which can be used as a substitute of rutile mineral

  15. Routing of individual polymers in designed patterns

    DEFF Research Database (Denmark)

    Knudsen, Jakob Bach; Liu, Lei; Kodal, Anne Louise Bank

    2015-01-01

    Synthetic polymers are ubiquitous in the modern world, but our ability to exert control over the molecular conformation of individual polymers is very limited. In particular, although the programmable self-assembly of oligonucleotides and proteins into artificial nanostructures has been...... demonstrated, we currently lack the tools to handle other types of synthetic polymers individually and thus the ability to utilize and study their single-molecule properties. Here we show that synthetic polymer wires containing short oligonucleotides that extend from each repeat can be made to assemble...... into arbitrary routings. The wires, which can be more than 200 nm in length, are soft and bendable, and the DNA strands allow individual polymers to self-assemble into predesigned routings on both two- and three-dimensional DNA origami templates. The polymers are conjugated and potentially conducting, and could...

  16. Routing of individual polymers in designed patterns

    Science.gov (United States)

    Knudsen, Jakob Bach; Liu, Lei; Bank Kodal, Anne Louise; Madsen, Mikael; Li, Qiang; Song, Jie; Woehrstein, Johannes B.; Wickham, Shelley F. J.; Strauss, Maximilian T.; Schueder, Florian; Vinther, Jesper; Krissanaprasit, Abhichart; Gudnason, Daniel; Smith, Anton Allen Abbotsford; Ogaki, Ryosuke; Zelikin, Alexander N.; Besenbacher, Flemming; Birkedal, Victoria; Yin, Peng; Shih, William M.; Jungmann, Ralf; Dong, Mingdong; Gothelf, Kurt V.

    2015-10-01

    Synthetic polymers are ubiquitous in the modern world, but our ability to exert control over the molecular conformation of individual polymers is very limited. In particular, although the programmable self-assembly of oligonucleotides and proteins into artificial nanostructures has been demonstrated, we currently lack the tools to handle other types of synthetic polymers individually and thus the ability to utilize and study their single-molecule properties. Here we show that synthetic polymer wires containing short oligonucleotides that extend from each repeat can be made to assemble into arbitrary routings. The wires, which can be more than 200 nm in length, are soft and bendable, and the DNA strands allow individual polymers to self-assemble into predesigned routings on both two- and three-dimensional DNA origami templates. The polymers are conjugated and potentially conducting, and could therefore be used to create molecular-scale electronic or optical wires in arbitrary geometries.

  17. A living foundry for Synthetic Biological Materials: A synthetic biology roadmap to new advanced materials

    Directory of Open Access Journals (Sweden)

    Rosalind A. Le Feuvre

    2018-06-01

    Full Text Available Society is on the cusp of harnessing recent advances in synthetic biology to discover new bio-based products and routes to their affordable and sustainable manufacture. This is no more evident than in the discovery and manufacture of Synthetic Biological Materials, where synthetic biology has the capacity to usher in a new Materials from Biology era that will revolutionise the discovery and manufacture of innovative synthetic biological materials. These will encompass novel, smart, functionalised and hybrid materials for diverse applications whose discovery and routes to bio-production will be stimulated by the fusion of new technologies positioned across physical, digital and biological spheres. This article, which developed from an international workshop held in Manchester, United Kingdom, in 2017 [1], sets out to identify opportunities in the new materials from biology era. It considers requirements, early understanding and foresight of the challenges faced in delivering a Discovery to Manufacturing Pipeline for synthetic biological materials using synthetic biology approaches. This challenge spans the complete production cycle from intelligent and predictive design, fabrication, evaluation and production of synthetic biological materials to new ways of bringing these products to market. Pathway opportunities are identified that will help foster expertise sharing and infrastructure development to accelerate the delivery of a new generation of synthetic biological materials and the leveraging of existing investments in synthetic biology and advanced materials research to achieve this goal. Keywords: Synthetic biology, Materials, Biological materials, Biomaterials, Advanced materials

  18. Production of BaAl_2O_4 doped with Eu"3"+ in low temperature: research of the influence of the synthesis route, temperature and calcination time in the optical properties

    International Nuclear Information System (INIS)

    Gomes, Manasses Almeida

    2017-01-01

    In this work, the synthesis condition (complexing agent and temperature and time of calcination) were studied aiming to produce BaAl_2O_4 samples in the ferroelectric hexagonal phase. Pure and Eu"3"+ - doped samples were produced and its luminescent properties were investigated. BaAl_2O_4 was prepared using several thermal treatment conditions, via an alternative sol-gel route, using coconut water or PVA as the complexing agents. The sample production at 600 °C/5h is quite interesting, since to date the lowest calcination temperatures found in the literature was 650 ° C using reagents with high degree of toxicity DTA / TG measurements indicated a possible start of the crystallization of the material at approximately 600 ° C, and the X-ray powder diffraction (XRD) confirm the formation of the desired phase of the calcined barium aluminate at that temperature. The results of the Rietveld refinements showed the occurrence of secondary phase in the samples produced at 600 ° C / 5h, presenting 5% of phase Ba(NO_3)_2, while single phase was found for samples calcined at 1200 ° C for 2 and 5h. Analysis of the diffractogram by the Scherrer equation showed smaller crystallite size for samples calcified at 600 °C/5h, but apparently with a lower degree of crystallinity than the sample prepared at 1200 ° C/ 2 and 5h. The photoluminescence measurements showed that the emission spectra of the samples have great dependence on the times, temperatures and complexing agents used. In particular, samples calcined at 600 ° C have very different characteristics with regard to the probabilities of emissions associated with Eu"3"+ when compared with samples produced at higher temperatures. Differences observed in the spectra of samples produced via different complexing agents are possibly due to defects created in the materials by impurities present in the coconut water. Samples produced using PVA present sites with higher symmetry, which was evidenced by a lower relative emission

  19. VINE ROUTES IN BULGARIA

    Directory of Open Access Journals (Sweden)

    Lyuben Hristov

    2015-03-01

    Full Text Available The article deals with a scheme for the modern vine route in Bulgaria. Five basic vine routes and one international, between Bulgaria, Macedonia and Greece are defined. All routes consider characteristic varieties of grapes and kinds of vine products. Vine tourist products combined with visits of important natural and anthropological object are in the bases of the defined routes. The described routes are an important contribution to development of alternative tourist products in the country.

  20. Quantum chemistry-assisted synthesis route development

    International Nuclear Information System (INIS)

    Hori, Kenji; Sumimoto, Michinori; Murafuji, Toshihiro

    2015-01-01

    We have been investigating “quantum chemistry-assisted synthesis route development” using in silico screenings and applied the method to several targets. Another example was conducted to develop synthesis routes for a urea derivative, namely 1-(4-(trifluoromethyl)-2-oxo-2H-chromen-7-yl)urea. While five synthesis routes were examined, only three routes passed the second in silico screening. Among them, the reaction of 7-amino-4-(trifluoromethyl)-2H-chromen-2-one and O-methyl carbamate with BF 3 as an additive was ranked as the first choice for synthetic work. We were able to experimentally obtain the target compound even though its yield was as low as 21 %. The theoretical result was thus consistent with that observed. The summary of transition state data base (TSDB) is also provided. TSDB is the key to reducing time of in silico screenings

  1. Natural - synthetic - artificial!

    DEFF Research Database (Denmark)

    Nielsen, Peter E

    2010-01-01

    The terms "natural," "synthetic" and "artificial" are discussed in relation to synthetic and artificial chromosomes and genomes, synthetic and artificial cells and artificial life.......The terms "natural," "synthetic" and "artificial" are discussed in relation to synthetic and artificial chromosomes and genomes, synthetic and artificial cells and artificial life....

  2. A living foundry for Synthetic Biological Materials: A synthetic biology roadmap to new advanced materials.

    Science.gov (United States)

    Le Feuvre, Rosalind A; Scrutton, Nigel S

    2018-06-01

    Society is on the cusp of harnessing recent advances in synthetic biology to discover new bio-based products and routes to their affordable and sustainable manufacture. This is no more evident than in the discovery and manufacture of Synthetic Biological Materials , where synthetic biology has the capacity to usher in a new Materials from Biology era that will revolutionise the discovery and manufacture of innovative synthetic biological materials. These will encompass novel, smart, functionalised and hybrid materials for diverse applications whose discovery and routes to bio-production will be stimulated by the fusion of new technologies positioned across physical, digital and biological spheres. This article, which developed from an international workshop held in Manchester, United Kingdom, in 2017 [1], sets out to identify opportunities in the new materials from biology era. It considers requirements, early understanding and foresight of the challenges faced in delivering a Discovery to Manufacturing Pipeline for synthetic biological materials using synthetic biology approaches. This challenge spans the complete production cycle from intelligent and predictive design, fabrication, evaluation and production of synthetic biological materials to new ways of bringing these products to market. Pathway opportunities are identified that will help foster expertise sharing and infrastructure development to accelerate the delivery of a new generation of synthetic biological materials and the leveraging of existing investments in synthetic biology and advanced materials research to achieve this goal.

  3. Synthetic Cannabinoids.

    Science.gov (United States)

    Mills, Brooke; Yepes, Andres; Nugent, Kenneth

    2015-07-01

    Synthetic cannabinoids (SCBs), also known under the brand names of "Spice," "K2," "herbal incense," "Cloud 9," "Mojo" and many others, are becoming a large public health concern due not only to their increasing use but also to their unpredictable toxicity and abuse potential. There are many types of SCBs, each having a unique binding affinity for cannabinoid receptors. Although both Δ-tetrahydrocannabinol (THC) and SCBs stimulate the same receptors, cannabinoid receptor 1 (CB1) and cannabinoid receptor 2 (CB2), studies have shown that SCBs are associated with higher rates of toxicity and hospital admissions than is natural cannabis. This is likely due to SCBs being direct agonists of the cannabinoid receptors, whereas THC is a partial agonist. Furthermore, the different chemical structures of SCBs found in Spice or K2 may interact in unpredictable ways to elicit previously unknown, and the commercial products may have unknown contaminants. The largest group of users is men in their 20s who participate in polydrug use. The most common reported toxicities with SCB use based on studies using Texas Poison Control records are tachycardia, agitation and irritability, drowsiness, hallucinations, delusions, hypertension, nausea, confusion, dizziness, vertigo and chest pain. Acute kidney injury has also been strongly associated with SCB use. Treatment mostly involves symptom management and supportive care. More research is needed to identify which contaminants are typically found in synthetic marijuana and to understand the interactions between different SBCs to better predict adverse health outcomes.

  4. Routing in opportunistic networks

    CERN Document Server

    Dhurandher, Sanjay; Anpalagan, Alagan; Vasilakos, Athanasios

    2013-01-01

    This book provides a comprehensive guide to selected topics, both ongoing and emerging, in routing in OppNets. The book is edited by worldwide technical leaders, prolific researchers and outstanding academics, Dr. Isaac Woungang and co-editors, Dr. Sanjay Kumar Dhurandher, Prof. Alagan Anpalagan and Prof. Athanasios Vasilakos. Consisting of contributions from well known and high profile researchers and scientists in their respective specialties, the main topics that are covered in this book include mobility and routing, social-aware routing, context-based routing, energy-aware routing, incentive-aware routing, stochastic routing, modeling of intermittent connectivity, in both infrastructure and infrastructure-less OppNets. Key Features: Discusses existing and emerging techniques for routing in infrastructure and infrastructure-less OppNets. Provides a unified covering of otherwise disperse selected topics on routing in infrastructure and infrastructure-less OppNets.  Includes a set of PowerPoint slides and g...

  5. Comparative study on upconversion luminescence and temperature sensing of α- and β-NaYF{sub 4}:Yb{sup 3+}/Er{sup 3+} nano-/micro-crystals derived from a microwave-assisted hydrothermal route

    Energy Technology Data Exchange (ETDEWEB)

    Tong, Lili [Department of Physics, Dalian Maritime University, Dalian 116026 (China); Li, Xiangping, E-mail: lixp@dlmu.edu.cn [Department of Physics, Dalian Maritime University, Dalian 116026 (China); Hua, Ruinian [College of Life Science, Dalian Nationalities University, Dalian 116600 (China); Li, Xuejing; Zheng, Hui; Sun, Jiashi; Zhang, Jinsu; Cheng, Lihong [Department of Physics, Dalian Maritime University, Dalian 116026 (China); Chen, Baojiu, E-mail: chenmbj@sohu.com [Department of Physics, Dalian Maritime University, Dalian 116026 (China)

    2015-11-15

    Yb{sup 3+}/Er{sup 3+} co-doped α- and β-phase NaYF{sub 4} nano-/micro-crystals were prepared through a microwave-assisted hydrothermal route. The crystal structure and microscopic morphology of the samples were characterized by means of X-ray diffraction (XRD) and scanning electron microscopy (SEM). Frequency upconverted emissions from the two thermally coupled excited state {sup 2}H{sub 11/2} and {sup 4}S{sub 3/2} levels of Er{sup 3+} in both phases of phosphors were recorded at temperatures ranging from room temperature to 573 K under 980 nm infrared laser excitation. The time scanning upconversion spectra were investigated in detail to reveal the thermal effect induced by laser irradiation and the luminescent thermal stability of the two phases NaYF{sub 4} polycrystals. Comparison of the upconversion luminescence and the sensitivity between the two phases NaYF{sub 4} polycrystals indicated that β-phase NaYF{sub 4} won much stronger luminescent intensity, better luminescent thermal stability, and higher temperature sensitivity. - Highlights: • Yb{sup 3+}/Er{sup 3+} codoped NaYF{sub 4} were prepared by a microwave-assisted hydrothermal route. • The UC luminescence and temperature sensing properties were studied. • Comparison of the UCL and the sensitivity between α- and β-phase samples were done. • Thermal effect and UCL thermo-stability were studied by time scanning UCL spectra. • β-phase sample won much better luminescent and temperature sensing properties.

  6. Preparation and Low Temperature Short-term Storage for Synthetic Seeds of Caladium bicolor

    Directory of Open Access Journals (Sweden)

    Mehpara MAQSOOD

    2015-03-01

    Full Text Available An efficient somatic embryo encapsulation and in vitro plant regeneration technique were established with Caladium bicolor, an important ornamental plant.Tuber derived embryogenic callus (95.50% was obtained on Murashige and Skoog (MS medium amended with 0.5 mg L-1 α-Naphthalene acetic acid (NAA + 0.5 mg L-1 6-Benzyladenine (BA. The embryogenic callus later differentiated into somatic embryos in the same plant growth regulators (PGRs added medium (NAA and BA. The induced embryos matured and developed into plantlets in NAA and BA added media; maximum plantlets development was observed at 1.0 mg L-1 NAA + 1.0 mg L-1 BA supplemented medium. Synthetic seeds were produced by encapsulating embryos in gel containing 3.0% sucrose + 3.0% sodium alginate and 100 mM of calcium chloride.The highest synthetic seed germination (97.6% was observed on medium supplemented with 1.0 mg L-1 NAA + 1.0 mg L-1 BA. The synthetic seeds were kept at low temperatures for storage; the encapsulated beads were viable and demonstrated good germination even after 12 weeks of storage at 4 °C. The plantlet recovery frequency was however declined with time. The synthetic seed derived plantlets were morphologically similar to the mother plant.

  7. Topotactic reduction as a synthetic route for the preparation of low-dimensional Mn(II) oxide phases: the structure and magnetism of LaAMnO(4-x) (A = Sr, Ba).

    Science.gov (United States)

    Kitchen, Helen J; Saratovsky, Ian; Hayward, Michael A

    2010-07-14

    Reaction of LaSrMnO(4) with CaH(2) at 420 degrees C yields LaSrMnO(3.67(3)). Raising the temperature to 480 degrees C yields the Mn(II) phase LaSrMnO(3.50(2)). Neutron powder diffraction data show both phases adopt body-centred orthorhombic crystal structures (LaSrMnO(3.67(3)), Immm: a = 3.7256(1) A, b = 3.8227(1) A, c = 13.3617(4) A; LaSrMnO(3.50(2)), Immm: a = 3.7810(1) A, b = 3.7936(1) A, c = 13.3974(3) A) with anion vacancies located within the equatorial MnO(2-x) planes of the materials. Analogous reactivity is observed between LaBaMnO(4) and CaH(2) to yield body-centred tetragonal reduced phases (LaBaMnO(3.53(3)), I4/mmm: a = 3.8872(1)A, c = 13.6438(2) A). Low-temperature neutron diffraction and magnetisation data show that LaSrMnO(3.5) and LaBaMnO(3.5) exhibit three-dimensional antiferromagnetic order below 155 K and 135 K respectively. Above these temperatures, they exhibit two-dimensional antiferromagnetic order with paramagnetic behaviour observed above 480 K in both phases. The origin of the low dimensional magnetic order and ordering of the anion vacancies in the reduced phases is discussed.

  8. Applying green chemistry to the photochemical route to artemisinin.

    Science.gov (United States)

    Amara, Zacharias; Bellamy, Jessica F B; Horvath, Raphael; Miller, Samuel J; Beeby, Andrew; Burgard, Andreas; Rossen, Kai; Poliakoff, Martyn; George, Michael W

    2015-06-01

    Artemisinin is an important antimalarial drug, but, at present, the environmental and economic costs of its semi-synthetic production are relatively high. Most of these costs lie in the final chemical steps, which follow a complex acid- and photo-catalysed route with oxygenation by both singlet and triplet oxygen. We demonstrate that applying the principles of green chemistry can lead to innovative strategies that avoid many of the problems in current photochemical processes. The first strategy combines the use of liquid CO2 as solvent and a dual-function solid acid/photocatalyst. The second strategy is an ambient-temperature reaction in aqueous mixtures of organic solvents, where the only inputs are dihydroartemisinic acid, O2 and light, and the output is pure, crystalline artemisinin. Everything else-solvents, photocatalyst and aqueous acid-can be recycled. Some aspects developed here through green chemistry are likely to have wider application in photochemistry and other reactions.

  9. Applying green chemistry to the photochemical route to artemisinin

    Science.gov (United States)

    Amara, Zacharias; Bellamy, Jessica F. B.; Horvath, Raphael; Miller, Samuel J.; Beeby, Andrew; Burgard, Andreas; Rossen, Kai; Poliakoff, Martyn; George, Michael W.

    2015-06-01

    Artemisinin is an important antimalarial drug, but, at present, the environmental and economic costs of its semi-synthetic production are relatively high. Most of these costs lie in the final chemical steps, which follow a complex acid- and photo-catalysed route with oxygenation by both singlet and triplet oxygen. We demonstrate that applying the principles of green chemistry can lead to innovative strategies that avoid many of the problems in current photochemical processes. The first strategy combines the use of liquid CO2 as solvent and a dual-function solid acid/photocatalyst. The second strategy is an ambient-temperature reaction in aqueous mixtures of organic solvents, where the only inputs are dihydroartemisinic acid, O2 and light, and the output is pure, crystalline artemisinin. Everything else—solvents, photocatalyst and aqueous acid—can be recycled. Some aspects developed here through green chemistry are likely to have wider application in photochemistry and other reactions.

  10. Synthetic Brainbows

    KAUST Repository

    Wan, Y.

    2013-06-01

    Brainbow is a genetic engineering technique that randomly colorizes cells. Biological samples processed with this technique and imaged with confocal microscopy have distinctive colors for individual cells. Complex cellular structures can then be easily visualized. However, the complexity of the Brainbow technique limits its applications. In practice, most confocal microscopy scans use different florescence staining with typically at most three distinct cellular structures. These structures are often packed and obscure each other in rendered images making analysis difficult. In this paper, we leverage a process known as GPU framebuffer feedback loops to synthesize Brainbow-like images. In addition, we incorporate ID shuffing and Monte-Carlo sampling into our technique, so that it can be applied to single-channel confocal microscopy data. The synthesized Brainbow images are presented to domain experts with positive feedback. A user survey demonstrates that our synthetic Brainbow technique improves visualizations of volume data with complex structures for biologists.

  11. Synthetic Botany.

    Science.gov (United States)

    Boehm, Christian R; Pollak, Bernardo; Purswani, Nuri; Patron, Nicola; Haseloff, Jim

    2017-07-05

    Plants are attractive platforms for synthetic biology and metabolic engineering. Plants' modular and plastic body plans, capacity for photosynthesis, extensive secondary metabolism, and agronomic systems for large-scale production make them ideal targets for genetic reprogramming. However, efforts in this area have been constrained by slow growth, long life cycles, the requirement for specialized facilities, a paucity of efficient tools for genetic manipulation, and the complexity of multicellularity. There is a need for better experimental and theoretical frameworks to understand the way genetic networks, cellular populations, and tissue-wide physical processes interact at different scales. We highlight new approaches to the DNA-based manipulation of plants and the use of advanced quantitative imaging techniques in simple plant models such as Marchantia polymorpha. These offer the prospects of improved understanding of plant dynamics and new approaches to rational engineering of plant traits. Copyright © 2017 Cold Spring Harbor Laboratory Press; all rights reserved.

  12. Hazmat Routes (National)

    Data.gov (United States)

    Department of Transportation — The Federal Motor Carrier Safety Administration (FMCSA) Hazardous Material Routes (NTAD) were developed using the 2004 First Edition TIGER/Line files. The routes are...

  13. State alternative route designations

    International Nuclear Information System (INIS)

    1989-07-01

    Pursuant to the Hazardous Materials Transportation Act (HMTA), the Department of Transportation (DOT) has promulgated a comprehensive set of regulations regarding the highway transportation of high-level radioactive materials. These regulations, under HM-164 and HM-164A, establish interstate highways as the preferred routes for the transportation of radioactive materials within and through the states. The regulations also provide a methodology by which a state may select alternative routes. First,the state must establish a ''state routing agency,'' defined as an entity authorized to use the state legal process to impose routing requirements on carriers of radioactive material (49 CFR 171.8). Once identified, the state routing agency must select routes in accordance with Large Quantity Shipments of Radioactive Materials or an equivalent routing analysis. Adjoining states and localities should be consulted on the impact of proposed alternative routes as a prerequisite of final route selection. Lastly, the states must provide written notice of DOT of any alternative route designation before the routes are deemed effective

  14. Biomimetic and Aggregation-Driven Crystallization Route for Room-Temperature Material Synthesis: Growth of β-Ga2O3 Nanoparticles Using Peptide Assemblies as Nanoreactors

    Science.gov (United States)

    Lee, Sang-Yup; Gao, Xueyun; Matsui, Hiroshi

    2008-01-01

    The room temperature synthesis of β-Ga2O3 nanocrystal was examined by coupling two biomimetic crystallization techniques, the enzymatic peptide nano-assembly templating and the aggregation-driven crystallization. The catalytic template of peptide assembly nucleated and mineralized primary β-Ga2O3 crystals, and then fused them to grow single-crystalline and monodisperse nanoparticles in the cavity of the peptide assembly at room temperature. In this work, the peptide assembly was exploited as a nano-reactor with an enzymatic functionality catalyzing the hydrolysis of gallium precursors. In addition, the characteristic ring-structure of peptide assembly is expected to provide an efficient dehydration pathway and the crystallization control over the surface tension, which are advantageous for the β-Ga2O3 crystal growth. This multifunctional peptide assembly could be applied for syntheses of a variety of nanomaterials that are kinetically difficult to grow at room temperature. PMID:17302413

  15. Study of Hopcalite (CuMnOx) Catalysts Prepared Through A Novel Route for the Oxidation of Carbon Monoxide at Low Temperature

    OpenAIRE

    Subhashish Dey; Ganesh Chandra Dhal; Devendra Mohan; Ram Prasad

    2017-01-01

    Carbon monoxide (CO) is a poisonous gas, recognized as a silent killer. The gas is produced by incomplete combustion of carbonaceous fuel. Recent studies have shown that hopcalite group is one of the promising catalysts for CO oxidation at low temperature. In this study, hopcalite (CuMnOx) catalysts were prepared by KMnO4 co-precipitation method followed by washing, drying the precipitate at different temperatures (22, 50, 90, 110, and 120 oC) for 12 h in an oven and subsequent calcination at...

  16. Effects of Temperature on the Microstructure and Magnetic Property of Cr-Doped ZnO DMS Prepared by Hydrothermal Route Assisted by Pulsed Magnetic Fields

    Directory of Open Access Journals (Sweden)

    Shiwei Wang

    2013-01-01

    Full Text Available In the present work, Cr-doped ZnO diluted magnetic semiconductor was synthesized by hydrothermal method under pulsed magnetic fields. The samples were characterized by XRD, SEM, VSM, Raman, and XPS techniques. Results demonstrated that Zn ions in the ZnO crystal lattice were partially displaced by Chromium (III ions. All samples show room temperature ferromagnetism which was enhanced by pulsed magnetic fields. The mechanism of ferromagnetism of Cr-doped ZnO particles was discussed.

  17. Synthetic fuels and fusion

    Energy Technology Data Exchange (ETDEWEB)

    Fillo, J A; Powell, J; Steinberg, M [Brookhaven National Lab., Upton, NY (USA)

    1981-03-01

    The decreasing availability of fossil fuels emphasizes the need to develop systems which will produce synthetic fuel to substitute for and supplement the natural supply. An important first step in the synthesis of liquid and gaseous fuels is the production of hydrogen. Thermonuclear fusion offers an inexhaustible source of energy for the production of hydrogen from water. Depending on design, electric generation efficiencies of approx. equal to 40-60% and hydrogen production efficiencies by high temperature electrolysis of approx. equal to 50-70% are projected for fusion reactors using high temperature blankets. Fusion/coal symbiotic systems appear economically promising for the first generation of commercial fusion synfuels plants. Coal production requirements and the environmental effects of large-scale coal usage would be greatly reduced by a fusion/coal system. In the long-term, there could be a gradual transition to an inexhaustible energy system based solely on fusion.

  18. New synthetic routes toward enantiopure nitrogen donor ligands.

    Science.gov (United States)

    Sala, Xavier; Rodríguez, Anna M; Rodríguez, Montserrat; Romero, Isabel; Parella, Teodor; von Zelewsky, Alexander; Llobet, Antoni; Benet-Buchholz, Jordi

    2006-12-08

    New polypyridylic chiral ligands, having either C3 or lower symmetry, have been prepared via a de novo construction of the pyridine nucleus by means of Kröhnke methodology in the key step. The chiral moieties of these ligands originate from the monoterpen chiral pool, namely (-)-alpha-pinene ((-)-14, (-)-15) and (-)-myrtenal ((-)-9, (-)-10). Extension of the above-mentioned asymmetric synthesis procedure to the preparation of enantiopure derivatives of some commonly used polypyridylic ligands has been achieved through a new aldehyde building block ((-)-16). As an example, the synthesis of a chiral derivative of N,N-bis(2-pyridylmethyl)ethylamine (bpea) ligand, (-)-19, has been performed to illustrate the viability of the method. The coordinative ability of the ligands has been tested through the synthesis and characterization of complexes [Mn((-)-19)Br2], (-)-20, and [RuCl((-)-10)(bpy)](BF4), (-)-21. Some preliminary results related to the enantioselective catalytic epoxidation of styrene with the ruthenium complex are also presented.

  19. New synthetic routes toward enantiopure nitrogen donor ligands

    OpenAIRE

    Sala, Xavier; Rodríguez, Anna M.; Rodríguez, Montserrat; Romero, Isabel; Parella, Teodor; Zelewsky, Alexander von; Llobet, Antoni; Benet-Buchholz, Jordi

    2008-01-01

    New polypyridylic chiral ligands, having either C₃ or lower symmetry, have been prepared via a de novo construction of the pyridine nucleus by means of Kröhnke methodology in the key step. The chiral moieties of these ligands originate from the monoterpen chiral pool, namely (-)-α-pinene ((-)-14, (-)-15) and (-)-myrtenal ((-)-9, (-)-10). Extension of the above-mentioned asymmetric synthesis procedure to the preparation of enantiopure derivatives of some commonly used polypyridylic ligands has...

  20. Boron-Based Nanostructures, Stability, Functionality and Synthetic Routes

    Energy Technology Data Exchange (ETDEWEB)

    Yakobson, Boris I. [Rice Univ., Houston, TX (United States); Ajayan, Pulickel M. [Rice Univ., Houston, TX (United States)

    2017-08-04

    Boron (B) is one of the most intriguing elements not only because of its position between metals and nonmetals in periodic table but also because of its ability to form an enormous number of allotropes. Apart from several bulk three-dimensional (3D) phases, boron can form 0D clusters, 1D nanotubes and nanowires, and 2D layers. In particular, boron sheets of monoatomic thickness have raised interest as a potential new 2D-material and as a (conceptual) precursor, for example, so-called α-sheets, from which other boron structures - fullerene cages and tubes - might be constructed. In fact, a number of planar B clusters up to tens of atoms, found in experiments, appear as seeds for extended sheets. In this project we developed theoretical methods to guide synthesis, have successfully identified the material substrates (Ag, Au, Cu) to producing the pure boron layers, and further even predicted what atomistic structures should be expected. These guidelines have successfully led to discoveries in several labs and now have grown into an active line of research worldwide.

  1. A Short Synthetic Route to the Calystegine Alkaloids

    DEFF Research Database (Denmark)

    Skaanderup, Philip Robert; Madsen, Robert

    2003-01-01

    An efficient strategy is described for the synthesis of enantiopure calystegine alkaloids. The key step employs a zinc-mediated fragmentation of benzyl-protected methyl 6-iodo-glycosides followed by in situ formation of the benzyl imine and Barbier-type allylation with zinc, magnesium, or indium...... metal. Stereochemistry in the pivotal allylation is controlled by the choice of the metal. The functionalized 1,8-nonadienes, thus formed, are converted into cycloheptenes by ring-closing metathesis. Regioselective hydroboration and oxidation give the corresponding cycloheptanones, which are deprotected...

  2. New Synthetic Routes to Furocoumarins and Their Analogs: A Review

    Directory of Open Access Journals (Sweden)

    Valery F. Traven

    2004-02-01

    Full Text Available Many furocoumarins and their analogs possess a prominent photobiological activity. Some of them are successfully used as drugs in phototherapy of skin diseases. Fries rearrangement of acyloxyheteroarenes, condensation of acylhydroxyheteroarenes with α-carbonyl compounds under base catalysis and transformations of dihydrofurocoumarinones are new trends in synthesis of furocoumarins and their analogs.

  3. Two Step Wittig/Dihydroxylation Synthetic Route to Higher Sugars

    DEFF Research Database (Denmark)

    Jørgensen, Morten; Madsen, Robert

    1999-01-01

    Higher carbon sugars are obtained by a two carbon, two step chain elongation of aldoses involving first a Wittig reaction and then an osmium tetroxide catalyzed dihydroxylation......Higher carbon sugars are obtained by a two carbon, two step chain elongation of aldoses involving first a Wittig reaction and then an osmium tetroxide catalyzed dihydroxylation...

  4. A concise synthetic route to the conduritols from pentoses

    DEFF Research Database (Denmark)

    Keinicke, Lise Edelmann; Madsen, Robert

    2005-01-01

    -bromopropenyl benzoate and occurs with good diastereoselectivity. An amino group can be introduced in the product by trapping the intermediate aldehyde as the imine prior to the allylation. The functionalised 1,7-octadienes, thus obtained, are converted into protected conduritols by ring-closing olefin...

  5. A New Synthetic Route to Dihydrobenzopyran Via Tandem Demethylation Cyclisation

    Directory of Open Access Journals (Sweden)

    G. Shanmugam

    2000-06-01

    Full Text Available A tandem demethylation-cyclisation reaction resulting in the formation of pyran rings using AlCl3/EtSH reagent under mild reaction conditions is reported. X-ray diffraction studies on the intermediate support the suggested mechanism.

  6. Shock compression of synthetic opal

    International Nuclear Information System (INIS)

    Inoue, A; Okuno, M; Okudera, H; Mashimo, T; Omurzak, E; Katayama, S; Koyano, M

    2010-01-01

    Structural change of synthetic opal by shock-wave compression up to 38.1 GPa has been investigated by using SEM, X-ray diffraction method (XRD), Infrared (IR) and Raman spectroscopies. Obtained information may indicate that the dehydration and polymerization of surface silanole due to high shock and residual temperature are very important factors in the structural evolution of synthetic opal by shock compression. Synthetic opal loses opalescence by 10.9 and 18.4 GPa of shock pressures. At 18.4 GPa, dehydration and polymerization of surface silanole and transformation of network structure may occur simultaneously. The 4-membered ring of TO 4 tetrahedrons in as synthetic opal may be relaxed to larger ring such as 6-membered ring by high residual temperature. Therefore, the residual temperature may be significantly high at even 18.4 GPa of shock compression. At 23.9 GPa, opal sample recovered the opalescence. Origin of this opalescence may be its layer structure by shock compression. Finally, sample fuse by very high residual temperature at 38.1 GPa and the structure closes to that of fused SiO 2 glass. However, internal silanole groups still remain even at 38.1 GPa.

  7. Shock compression of synthetic opal

    Science.gov (United States)

    Inoue, A.; Okuno, M.; Okudera, H.; Mashimo, T.; Omurzak, E.; Katayama, S.; Koyano, M.

    2010-03-01

    Structural change of synthetic opal by shock-wave compression up to 38.1 GPa has been investigated by using SEM, X-ray diffraction method (XRD), Infrared (IR) and Raman spectroscopies. Obtained information may indicate that the dehydration and polymerization of surface silanole due to high shock and residual temperature are very important factors in the structural evolution of synthetic opal by shock compression. Synthetic opal loses opalescence by 10.9 and 18.4 GPa of shock pressures. At 18.4 GPa, dehydration and polymerization of surface silanole and transformation of network structure may occur simultaneously. The 4-membered ring of TO4 tetrahedrons in as synthetic opal may be relaxed to larger ring such as 6-membered ring by high residual temperature. Therefore, the residual temperature may be significantly high at even 18.4 GPa of shock compression. At 23.9 GPa, opal sample recovered the opalescence. Origin of this opalescence may be its layer structure by shock compression. Finally, sample fuse by very high residual temperature at 38.1 GPa and the structure closes to that of fused SiO2 glass. However, internal silanole groups still remain even at 38.1 GPa.

  8. Shock compression of synthetic opal

    Energy Technology Data Exchange (ETDEWEB)

    Inoue, A; Okuno, M; Okudera, H [Department of Earth Sciences, Kanazawa University Kanazawa, Ishikawa, 920-1192 (Japan); Mashimo, T; Omurzak, E [Shock Wave and Condensed Matter Research Center, Kumamoto University, Kumamoto, 860-8555 (Japan); Katayama, S; Koyano, M, E-mail: okuno@kenroku.kanazawa-u.ac.j [JAIST, Nomi, Ishikawa, 923-1297 (Japan)

    2010-03-01

    Structural change of synthetic opal by shock-wave compression up to 38.1 GPa has been investigated by using SEM, X-ray diffraction method (XRD), Infrared (IR) and Raman spectroscopies. Obtained information may indicate that the dehydration and polymerization of surface silanole due to high shock and residual temperature are very important factors in the structural evolution of synthetic opal by shock compression. Synthetic opal loses opalescence by 10.9 and 18.4 GPa of shock pressures. At 18.4 GPa, dehydration and polymerization of surface silanole and transformation of network structure may occur simultaneously. The 4-membered ring of TO{sub 4} tetrahedrons in as synthetic opal may be relaxed to larger ring such as 6-membered ring by high residual temperature. Therefore, the residual temperature may be significantly high at even 18.4 GPa of shock compression. At 23.9 GPa, opal sample recovered the opalescence. Origin of this opalescence may be its layer structure by shock compression. Finally, sample fuse by very high residual temperature at 38.1 GPa and the structure closes to that of fused SiO{sub 2} glass. However, internal silanole groups still remain even at 38.1 GPa.

  9. Novel routes to nanodispersed semiconductors

    International Nuclear Information System (INIS)

    Green, M.A.

    1999-01-01

    Novel synthetic routes to nanodispersed compound semiconductors using organometallic precursors have been developed. The quantum dots have been studied by optical absorption spectroscopy, photoluminescence spectroscopy, transmission electron microscopy, high resolution transmission electron microscopy, infra red spectroscopy and nuclear magnetic resonance. Polar Lewis base solvents such as tri-n-octylphosphine oxide and 4-ethylpyridine were utilized as both passivating agent and dispersing medium. In the the search for new solvent systems and passivating agents, and investigation was also made into the use of dimethyl sulfoxide as a reaction solvent and capping agent in the preparation of nanocrystalline CdS. Existing routes using metal alkyls and silylated precursors in hot TOPO were improved by substituting the metal alkyl with an metal alkyl adduct. Cadmium monothiocarbamate and a related precursor, cadmium thioacetate were investigated as possible single source precursors to nanometer sized CdS. The thermolysis of diorganophosphides in the Lewis bases coordinating solvent (4-ethylpridine) has been investigated, including studies of decompositon mechanisms, and quantum dots of Cd 3 P 2 , Zn 3 P 2 , Inp and GaP have been prepared. The synthesis of InAs using the metal chloride and an aminoarsenide precursor in 4-ethylpridine has also been developed. A simple method for the organization of III-V materials into glass like aggregates has been described. (author)

  10. Alternating copolymerization of propylene oxide with biorenewable terpene-based cyclic anhydrides: a sustainable route to aliphatic polyesters with high glass transition temperatures.

    Science.gov (United States)

    Van Zee, Nathan J; Coates, Geoffrey W

    2015-02-23

    The alternating copolymerization of propylene oxide with terpene-based cyclic anhydrides catalyzed by chromium, cobalt, and aluminum salen complexes is reported. The use of the Diels-Alder adduct of α-terpinene and maleic anhydride as the cyclic anhydride comonomer results in amorphous polyesters that exhibit glass transition temperatures (Tg ) of up to 109 °C. The polymerization conditions and choice of catalyst have a dramatic impact on the molecular weight distribution, the relative stereochemistry of the diester units along the polymer chain, and ultimately the Tg of the resulting polymer. The aluminum salen complex exhibits exceptional selectivity for copolymerization without transesterification or epimerization side reactions. The resulting polyesters are highly alternating and have high molecular weights and narrow polydispersities. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Nanoparticles of nickel oxide: growth and organization on zinc-substituted anionic clay matrix by one-pot route at room temperature

    International Nuclear Information System (INIS)

    Carja, Gabriela; Nakajima, Akira; Dranca, Cristian; Okada, Kiyoshi

    2010-01-01

    A room temperature nanocarving strategy is developed for the fabrication of nanoparticles of nickel oxide on zinc-substituted anionic clay matrix (Ni/ZnLDH). It is based on the growth and organization of nanoparticles of nickel oxide which occur during the structural reconstruction of the layered structure of the anionic clay in NiSO 4 aqueous solution. No organic compounds are used during the fabrication. The described material was characterized by X-ray diffraction (XRD), IR spectroscopy (FTIR), transmission electron microscopy (TEM), field-emission scanning electron microscopy (FESEM), energy dispersive X-ray (EDX) spectroscopy, and X-ray photoelectron spectroscopy (XPS). Results show that the nickel-clay nanoarchitecture consists of small nanoparticles of nickel oxide (average size 7 nm) deposited on the larger nanoparticles (average size 90 nm) of zinc-substituted clay. The optical properties of the new nickel-zinc formulation are studied by UV-Vis.

  12. Nanoparticles of nickel oxide: growth and organization on zinc-substituted anionic clay matrix by one-pot route at room temperature

    Science.gov (United States)

    Carja, Gabriela; Nakajima, Akira; Dranca, Cristian; Okada, Kiyoshi

    2010-10-01

    A room temperature nanocarving strategy is developed for the fabrication of nanoparticles of nickel oxide on zinc-substituted anionic clay matrix (Ni/ZnLDH). It is based on the growth and organization of nanoparticles of nickel oxide which occur during the structural reconstruction of the layered structure of the anionic clay in NiSO4 aqueous solution. No organic compounds are used during the fabrication. The described material was characterized by X-ray diffraction (XRD), IR spectroscopy (FTIR), transmission electron microscopy (TEM), field-emission scanning electron microscopy (FESEM), energy dispersive X-ray (EDX) spectroscopy, and X-ray photoelectron spectroscopy (XPS). Results show that the nickel-clay nanoarchitecture consists of small nanoparticles of nickel oxide (average size 7 nm) deposited on the larger nanoparticles (average size 90 nm) of zinc-substituted clay. The optical properties of the new nickel-zinc formulation are studied by UV-Vis.

  13. A new chemical route to a hybrid nanostructure: room-temperature solid-state reaction synthesis of Ag@AgCl with efficient photocatalysis.

    Science.gov (United States)

    Hu, Pengfei; Cao, Yali

    2012-08-07

    The room-temperature solid-state chemical reaction technique has been used to synthesize the silver nanoparticle-loaded semiconductor silver@silver chloride for the first time. It has the advantages of convenient operation, lower cost, less pollution, and mass production. This simple technique created a wide array of nanosized silver particles which had a strong surface plasmon resonance effect in the visible region, and built up an excellent composite structure of silver@silver chloride hybrid which exhibited high photocatalytic activity and stability towards decomposition of organic methyl orange under visible-light illumination. Moreover, this work achieved the control of composition of the silver@silver chloride composite simply by adjusting the feed ratio of reactants. It offers an alternative method for synthesising metal@semiconductor composites.

  14. Development of CuInTe{sub 2} thin film solar cells by electrochemical route with low temperature (80 °C) heat treatment procedure

    Energy Technology Data Exchange (ETDEWEB)

    Lakhe, Manorama [Electrochemical Laboratory, Department of Physics, Savitribai Phule Pune University, Pune 411007 (India); Mahapatra, S.K. [Department of Applied Physics, Birla Institute of Technology, Mesra, Ranchi 835215 (India); Chaure, Nandu B., E-mail: n.chaure@physics.unipune.ac.in [Electrochemical Laboratory, Department of Physics, Savitribai Phule Pune University, Pune 411007 (India)

    2016-02-15

    Graphical abstract: Dark and illuminated J–V characteristic for Cell B, successively heat treated at 80 °C for 60 min and corresponding dV/d(J + J{sub L}) versus 1/(J + J{sub L}) plot. Efficiency, η = 3.8%, series resistance, R{sub s} = 43 Ω and ideality factor, n = 1.9 are measured for Cell B. - Highlights: • Temperature, 80 °C is sufficient to produce highly crystalline CuInTe{sub 2} thin films. • Stoichiometric, uniform and well adherent thin films of CuInTe{sub 2} were electrodeposited. • 3.8% efficiency was measured for a cell prepared by successive heat treatment at 80 °C. • ‘R{sub s}’ and ‘n’ investigated for Cell A and B were 47, 43 Ω and 2.0 and 1.9, respectively. - Abstract: The effect of successive low-temperature heat treatment on the properties of electrodeposited CuInTe{sub 2} (CIT) thin films is investigated. The electrodeposition potential, −0.8 V versus Ag/AgCl was optimized by cyclic voltammetry onto CdS coated Fluorine doped tin oxide substrate. The samples were successively heat treated at 80 °C for 5, 30 and 60 min in an air ambient. The structural, morphological, compositional, electrical and optoelectronic properties were studied using XRD, Raman spectroscopy, SEM, FESEM, EDS, Current–Voltage and Capacitance–Voltage measurements. As-prepared CIT film exhibited amorphous nature, whereas the systematic development in the crystallinity was observed in successively heat treated samples. Compact, densely packed, globular surface morphology was observed. The Cu/In ratio was found to be increased systematically from 0.60 to 0.82 with heat treatment duration. The solar cell devices successively heat treated at 80 °C for 30 and 60 min measured an efficiency (η), 3.4% and 3.8%, respectively.

  15. One crop breeding cycle from starvation? How engineering crop photosynthesis for rising CO2 and temperature could be one important route to alleviation.

    Science.gov (United States)

    Kromdijk, Johannes; Long, Stephen P

    2016-03-16

    Global climate change is likely to severely impact human food production. This comes at a time when predicted demand for primary foodstuffs by a growing human population and changing global diets is already outpacing a stagnating annual rate of increase in crop productivity. Additionally, the time required by crop breeding and bioengineering to release improved varieties to farmers is substantial, meaning that any crop improvements needed to mitigate food shortages in the 2040s would need to start now. In this perspective, the rationale for improvements in photosynthetic efficiency as a breeding objective for higher yields is outlined. Subsequently, using simple simulation models it is shown how predicted changes in temperature and atmospheric [CO2] affect leaf photosynthetic rates. The chloroplast accounts for the majority of leaf nitrogen in crops. Within the chloroplast about 25% of nitrogen is invested in the carboxylase, Rubisco, which catalyses the first step of CO2 assimilation. Most of the remaining nitrogen is invested in the apparatus to drive carbohydrate synthesis and regenerate ribulose-1:5-bisphosphate (RuBP), the CO2-acceptor molecule at Rubisco. At preindustrial [CO2], investment in these two aspects may have been balanced resulting in co-limitation. At today's [CO2], there appears to be over-investment in Rubisco, and despite the counter-active effects of rising temperature and [CO2], this imbalance is predicted to worsen with global climate change. By breeding or engineering restored optimality under future conditions increased productivity could be achieved in both tropical and temperate environments without additional nitrogen fertilizer. Given the magnitude of the potential shortfall, better storage conditions, improved crop management and better crop varieties will all be needed. With the short time-scale at which food demand is expected to outpace supplies, all available technologies to improve crop varieties, from classical crop breeding to

  16. A bio-inspired zinc finger analogue anchored in 2D hexagonal meso-porous silica for room temperature CO_2 activation via a hydrogeno-carbonate route

    International Nuclear Information System (INIS)

    Doghri, Hanene; Baranova, Elena A.; Albela, Belen; Bonneviot, Laurent; Mongia Said-Zina

    2017-01-01

    Bio-inspired diethylenetriamine-zinc(II) complexes were anchored into the nano-pores of hexagonal meso-porous MCM41-like silicas targeting a carbamate free and low temperature CO_2 recycling process. A step-by-step approach was adopted to perform an in situ synthesis in order to mimic the zinc finger of carbonic anhydrases, the fastest family of enzymes. In the presence of a surface-masking pattern of TMA"+ ions, some silanol groups were capped using grafted trimethylsilyl functions, TMSgr, (gr for grafted). After removing the masking ions, a tridentate diethylenetriamine ligand was anchored using diethylenetriamine propyl-trimethoxysilane. The so-called DETA_a_n ligands (an for anchored) were partially mono-protonated using either cyclohexane or isopropanol as a solvent. Nonetheless, up to two thirds of them were metallated by Zn(II) ions, leading to the targeted anchored zinc finger mimic [Zn(DETAan)L]+(L = Cl or OH). CO_2 is then adsorbed at room temperature and in humid ambient air by the formation of an intermediate hydrogeno-carbonate-zinc complex. Specific IR signatures at 1330 and 1400 cm"-"1 together with characteristic C 1s and Zn 2p3/2 XPS binding energies at 286.4 and 1024.6 eV advocate for a rather symmetrical bidentate [η"2-CO_3] structural unit in the anchored complex [Zn(DETA_a_n)(η"2-HCO_3"*)]"+, where the Zn(II) ion is most likely penta-coordinated. The internal pH value varied by less than 0.5 depending on the metal reacting with the DETA_a_n ligand and its ability to generate HCO_3"-, due to the buffering effect of surface silanol and amino groups according to the level of protonation of the DETA moieties measured from the N 1s XPS spectra. In contrast to nitrate ions, chloride ions were found to inhibit the formation of hydrogeno-carbonate. (authors)

  17. A Plasma-Assisted Route to the Rapid Preparation of Transition-Metal Phosphides for Energy Conversion and Storage

    KAUST Repository

    Liang, Hanfeng

    2017-06-06

    Transition-metal phosphides (TMPs) are important materials that have been widely used in catalysis, supercapacitors, batteries, sensors, light-emitting diodes, and magnets. The physical and chemical structure of a metal phosphide varies with the method of preparation as the electronic, catalytic, and magnetic properties of the metal phosphides strongly depend on their synthesis routes. Commonly practiced processes such as solid-state synthesis and ball milling have proven to be reliable routes to prepare TMPs but they generally require high temperature and long reaction time. Here, a recently developed plasma-assisted conversion route for the preparation of TMPs is reviewed, along with their applications in energy conversion and storage, including water oxidation electrocatalysis, sodium-ion batteries, and supercapacitors. The plasma-assisted synthetic route should open up a new avenue to prepare TMPs with tailored structure and morphology for various applications. In fact, the process may be further extended to the synthesis of a wide range of transition-metal compounds such as borides and fluorides at low temperature and in a rapid manner.

  18. Evidence for single-chain magnet behavior in a Mn(III)-Ni(II) chain designed with high spin magnetic units: a route to high temperature metastable magnets.

    Science.gov (United States)

    Clérac, Rodolphe; Miyasaka, Hitoshi; Yamashita, Masahiro; Coulon, Claude

    2002-10-30

    We herein present the synthesis, crystal structure, and magnetic properties of a new heterometallic chain of MnIII and NiII ions, [Mn2(saltmen)2Ni(pao)2(py)2](ClO4)2 (1) (saltmen2- = N,N'-(1,1,2,2-tetramethylethylene) bis(salicylideneiminate) and pao- = pyridine-2-aldoximate). The crystal structure of 1 was investigated by X-ray crystallographic analysis: compound 1 crystallized in monoclinic, space group C2/c (No. 15) with a = 21.140(3) A, b = 15.975(1) A, c = 18.6212(4) A, beta = 98.0586(4) degrees , V = 6226.5(7) A3, and Z = 4. This compound consists of two fragments, the out-of-plane dimer [Mn2(saltmen)2]2+ as a coordination acceptor building block and the neutral mononuclear unit [Ni(pao)2(py)2] as a coordination donor building block, forming an alternating chain having the repeating unit [-Mn-(O)2-Mn-ON-Ni-NO-]n. In the crystal structure, each chain is well separated with a minimum intermetallic distance between Mn and Ni ions of 10.39 A and with the absence of interchain pi overlaps between organic ligands. These features ensure a good magnetic isolation of the chains. The dc and ac magnetic measurements were performed on both the polycrystalline sample and the aligned single crystals of 1. Above 30 K, the magnetic susceptibility of this one-dimensional compound was successfully described in a mean field approximation as an assembly of trimers (Mn...Ni...Mn) with a NiII...MnIII antiferromagnetic interaction (J = -21 K) connected through a ferromagnetic MnIII...MnIII interaction (J'). However, the mean field theory fails to describe the magnetic behavior below 30 K emphasizing the one-dimensional magnetic character of the title compound. Between 5 and 15 K, the susceptibility in the chain direction was fitted to a one-dimensional Ising model leading to the same value of J'. Hysteresis loops are observed below 3.5 K, indicating a magnet-type behavior. In the same range of temperature, combined ac and dc measurements show a slow relaxation of the magnetization

  19. Synthetic lubricating oils

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez Jurado, J

    1953-01-01

    A yellow solid petroleum paraffin d/sup 60/ 0.808, I number 3.5, average molecular weight 350, chlorinated and condensed with benzene, xylene, or naphthalene by the Friedel and Crafts reaction, in the presence of anhydrous AlCl/sub 3/ or activated Al, gave synthetic lubricating oils. Xylene was the preferred aromatic compound, naphthalene required the use of less completely chlorinated paraffin, benzene produced resins difficult to remove and gave darker oils with excessive green fluorescence. Activated Al rather than anhydrous AlCl/sub 3/ gave darker oils with higher viscosity and Conradson C values. Tar from the low-temperature distillation of lignite, used as a source of a paraffin fraction melting 40/sup 0/ to 48/sup 0/ (chlorinated to 26.5 percent Cl) and an aromatic fraction, 45 percent aromatic compounds by volume (mainly polysubstituted benzenes), I number 10, was converted to a similar synthetic lubricant with the following properties: Kinematic viscosity at 210/sup 0/ F., 50.4 centistokes; viscosity index, 92; Conradson C, 1.5 percent; solidification point, 9/sup 0/; S, 0.41 percent.

  20. Understanding individual routing behaviour.

    Science.gov (United States)

    Lima, Antonio; Stanojevic, Rade; Papagiannaki, Dina; Rodriguez, Pablo; González, Marta C

    2016-03-01

    Knowing how individuals move between places is fundamental to advance our understanding of human mobility (González et al. 2008 Nature 453, 779-782. (doi:10.1038/nature06958)), improve our urban infrastructure (Prato 2009 J. Choice Model. 2, 65-100. (doi:10.1016/S1755-5345(13)70005-8)) and drive the development of transportation systems. Current route-choice models that are used in transportation planning are based on the widely accepted assumption that people follow the minimum cost path (Wardrop 1952 Proc. Inst. Civ. Eng. 1, 325-362. (doi:10.1680/ipeds.1952.11362)), despite little empirical support. Fine-grained location traces collected by smart devices give us today an unprecedented opportunity to learn how citizens organize their travel plans into a set of routes, and how similar behaviour patterns emerge among distinct individual choices. Here we study 92 419 anonymized GPS trajectories describing the movement of personal cars over an 18-month period. We group user trips by origin-destination and we find that most drivers use a small number of routes for their routine journeys, and tend to have a preferred route for frequent trips. In contrast to the cost minimization assumption, we also find that a significant fraction of drivers' routes are not optimal. We present a spatial probability distribution that bounds the route selection space within an ellipse, having the origin and the destination as focal points, characterized by high eccentricity independent of the scale. While individual routing choices are not captured by path optimization, their spatial bounds are similar, even for trips performed by distinct individuals and at various scales. These basic discoveries can inform realistic route-choice models that are not based on optimization, having an impact on several applications, such as infrastructure planning, routing recommendation systems and new mobility solutions. © 2016 The Author(s).

  1. Synthetic biology, inspired by synthetic chemistry.

    Science.gov (United States)

    Malinova, V; Nallani, M; Meier, W P; Sinner, E K

    2012-07-16

    The topic synthetic biology appears still as an 'empty basket to be filled'. However, there is already plenty of claims and visions, as well as convincing research strategies about the theme of synthetic biology. First of all, synthetic biology seems to be about the engineering of biology - about bottom-up and top-down approaches, compromising complexity versus stability of artificial architectures, relevant in biology. Synthetic biology accounts for heterogeneous approaches towards minimal and even artificial life, the engineering of biochemical pathways on the organismic level, the modelling of molecular processes and finally, the combination of synthetic with nature-derived materials and architectural concepts, such as a cellular membrane. Still, synthetic biology is a discipline, which embraces interdisciplinary attempts in order to have a profound, scientific base to enable the re-design of nature and to compose architectures and processes with man-made matter. We like to give an overview about the developments in the field of synthetic biology, regarding polymer-based analogs of cellular membranes and what questions can be answered by applying synthetic polymer science towards the smallest unit in life, namely a cell. Copyright © 2012 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.

  2. Low temperature synthesis of N-doped TiO_2 with rice-like morphology through peroxo assisted hydrothermal route: Materials characterization and photocatalytic properties

    International Nuclear Information System (INIS)

    Bakar, Shahzad Abu; Ribeiro, Caue

    2016-01-01

    Highlights: • The N:TiO_2 nanorice were prepared using facile peroxo-assisted hydrothermal method at low temperature. • The N:TiO_2 exhibited rice-like morphology. • The nitrogen doping favoured UV/visible light photocatalytic activity. • The RhB and Atrazine were chosen as model pollutants. - Abstract: Nanorice-shaped N:TiO_2 photocatalysts have been prepared by the peroxo assisted hydrothermal method using stabilized titanium complex as a precursor and urea as a N source. The N:TiO_2 nanorices were characterised by XRD, FE-SEM, HRTEM, XPS, UV–vis spectroscopy, Raman spectroscopy and measurements of photocatalytic degradation of organic molecules (atrazine and RhB dye) under the UV and visible-light irradiation. XRD analyses showed that pristine TiO_2 crystallizes into anatase polymorph and that the N-doping process at 5% introduced a degree of disorder on the TiO_2 crystalline structure. XPS study revealed the successful incorporation of the nitrogen atoms at the interstitial sites of the TiO_2 crystal lattice. Microscopy studies revealed that the particle size was in the range 50–80 nm for the pristine TiO_2. The photocatalysts were assembled in the form of nanorices with a high surface area (102 m"2 g"−"1). The successful incorporation of nitrogen atoms into the TiO_2 crystal lattice is expected to be responsible for enhanced photocatalytic activity of the as-prepared samples for the degradation of pollutants (RhB and atrazine) under UV and visible light irradiation. The rate of ·OH radicals formation under visible-light irradiation was examined and found to be correlated with the photocatalytic activity per unit surface area. The N:TiO_2 particles with nanorice morphology was efficient photocatalysts for decomposition of organic dyes under UV and visible-light exposure while pristine TiO_2 photocatalyst did not show any significant photocatalytic activity when stimulated by visible-light. The 3% doped N:TiO_2 sample exhibited the highest

  3. Low temperature synthesis of N-doped TiO{sub 2} with rice-like morphology through peroxo assisted hydrothermal route: Materials characterization and photocatalytic properties

    Energy Technology Data Exchange (ETDEWEB)

    Bakar, Shahzad Abu, E-mail: shahzad.158@gmail.com [Department of Chemistry, Federal University of São Carlos, Washington Luiz Highway, km 235, 13565-905 São Carlos, SP (Brazil); Embrapa CNPDIA, XV de Novembro Street, 1452, CP 741, 13560-970 São Carlos, SP (Brazil); Ribeiro, Caue [Embrapa CNPDIA, XV de Novembro Street, 1452, CP 741, 13560-970 São Carlos, SP (Brazil)

    2016-07-30

    Highlights: • The N:TiO{sub 2} nanorice were prepared using facile peroxo-assisted hydrothermal method at low temperature. • The N:TiO{sub 2} exhibited rice-like morphology. • The nitrogen doping favoured UV/visible light photocatalytic activity. • The RhB and Atrazine were chosen as model pollutants. - Abstract: Nanorice-shaped N:TiO{sub 2} photocatalysts have been prepared by the peroxo assisted hydrothermal method using stabilized titanium complex as a precursor and urea as a N source. The N:TiO{sub 2} nanorices were characterised by XRD, FE-SEM, HRTEM, XPS, UV–vis spectroscopy, Raman spectroscopy and measurements of photocatalytic degradation of organic molecules (atrazine and RhB dye) under the UV and visible-light irradiation. XRD analyses showed that pristine TiO{sub 2} crystallizes into anatase polymorph and that the N-doping process at 5% introduced a degree of disorder on the TiO{sub 2} crystalline structure. XPS study revealed the successful incorporation of the nitrogen atoms at the interstitial sites of the TiO{sub 2} crystal lattice. Microscopy studies revealed that the particle size was in the range 50–80 nm for the pristine TiO{sub 2}. The photocatalysts were assembled in the form of nanorices with a high surface area (102 m{sup 2} g{sup −1}). The successful incorporation of nitrogen atoms into the TiO{sub 2} crystal lattice is expected to be responsible for enhanced photocatalytic activity of the as-prepared samples for the degradation of pollutants (RhB and atrazine) under UV and visible light irradiation. The rate of ·OH radicals formation under visible-light irradiation was examined and found to be correlated with the photocatalytic activity per unit surface area. The N:TiO{sub 2} particles with nanorice morphology was efficient photocatalysts for decomposition of organic dyes under UV and visible-light exposure while pristine TiO{sub 2} photocatalyst did not show any significant photocatalytic activity when stimulated by visible

  4. High-temperature crystal chemistry of layered calcium borosilicates: CaBSiO4(OH) (datolite), Ca4B5Si3O15(OH)5 (`bakerite') and Ca2B2SiO7 (synthetic analogue of okayamalite)

    Science.gov (United States)

    Krzhizhanovskaya, Maria G.; Gorelova, L. A.; Bubnova, R. S.; Pekov, I. V.; Krivovichev, S. V.

    2018-05-01

    The high-temperature behaviour of three Ca borosilicates has been studied by in situ powder high-temperature X-ray diffraction (HTXRD), differential scanning calorimetry and thermogravimetry in the temperature range 30-900 °C for natural samples of datolite, CaBSiO4(OH), and `bakerite', Ca4B5Si3O15(OH)5, and a synthetic analogue of okayamalite, Ca2B2SiO7. The latter was obtained by heating datolite at 800 °C for 5 h. Datolite and bakerite start to dehydroxylate above 700 and 500 °C, respectively, and decompose fully to form a high-temperature modification of okayamalite, HT-Ca2B2SiO7, and wollastonite, CaSiO3 at about 730 °C. Above 900 °C, HT-okayamalite decomposes with the formation of wollastonite, CaSiO3, and metaborate CaB2O4. The latter melts at about 990 °C. Above 1000 °C, only the existence of wollastonite, CaSiO3 and cristobalite, SiO2 was observed. According to the HTXRD data, in the temperature range 30-500 °C, datolite and `bakerite' demonstrate very similar and relatively low volumetric thermal expansion: α v = 29 and 27 × 10-6 °C-1, respectively. A high thermal expansion anisotropy ( α max/ α min 3) is caused by both the layered character of the crystal structures and the shear deformations of their monoclinic unit cells. The direction of maximum expansion is intermediate between the normal direction to the layers and the ( a + c) vector. A possible transformation mechanism from the datolite to the okayamalite structure topology is proposed from geometrical considerations. The synthetic analogue of okayamalite, Ca2B2SiO7, undergoes a reversible polymorphic transition at about 550 °C with a decrease in symmetry from tetragonal to orthorhombic. The crystal structure of the high-temperature (HT) modification of okayamalite was solved from the powder-diffraction data [900 °C: P21212, a = 7.3361(4), b = 7.1987(4), c = 4.8619(4) Å, V = 256.76(3) Å3, R wp = 6.61, R Bragg = 2.68%].

  5. Routing and scheduling problems

    DEFF Research Database (Denmark)

    Reinhardt, Line Blander

    couple of decades. To deliver competitive service and price, transportation today needs to be cost effective. A company requiring for things to be shipped will aim at having the freight shipped as cheaply as possible while often satisfying certain time constraints. For the transportation company......, the effectiveness of the network is of importance aiming at satisfying as many costumer demands as possible at a low cost. Routing represent a path between locations such as an origin and destination for the object routed. Sometimes routing has a time dimension as well as the physical paths. This may...... set cost making the cost of the individual vehicle routes inter-dependant. Depending on the problem type, the size of the problems and time available for solving, different solution methods can be applicable. In this thesis both heuristic methods and several exact methods are investigated depending...

  6. Class network routing

    Science.gov (United States)

    Bhanot, Gyan [Princeton, NJ; Blumrich, Matthias A [Ridgefield, CT; Chen, Dong [Croton On Hudson, NY; Coteus, Paul W [Yorktown Heights, NY; Gara, Alan G [Mount Kisco, NY; Giampapa, Mark E [Irvington, NY; Heidelberger, Philip [Cortlandt Manor, NY; Steinmacher-Burow, Burkhard D [Mount Kisco, NY; Takken, Todd E [Mount Kisco, NY; Vranas, Pavlos M [Bedford Hills, NY

    2009-09-08

    Class network routing is implemented in a network such as a computer network comprising a plurality of parallel compute processors at nodes thereof. Class network routing allows a compute processor to broadcast a message to a range (one or more) of other compute processors in the computer network, such as processors in a column or a row. Normally this type of operation requires a separate message to be sent to each processor. With class network routing pursuant to the invention, a single message is sufficient, which generally reduces the total number of messages in the network as well as the latency to do a broadcast. Class network routing is also applied to dense matrix inversion algorithms on distributed memory parallel supercomputers with hardware class function (multicast) capability. This is achieved by exploiting the fact that the communication patterns of dense matrix inversion can be served by hardware class functions, which results in faster execution times.

  7. Proxies for Anonymous Routing

    National Research Council Canada - National Science Library

    Reed, Michael G; Syverson, Paul F; Goldschlag, David M

    1996-01-01

    ...), and file transfers (FTP) have been implemented. Onion routing provides application independent, real-time, and bi-directional anonymous connections that are resistant to both eavesdropping and traffic analysis...

  8. Routes and Stations

    Data.gov (United States)

    Department of Homeland Security — he Routes_Stations table is composed of fixed rail transit systems within the Continental United States, Alaska, Hawaii, the District of Columbia, and Puerto Rico....

  9. Plant synthetic biology.

    Science.gov (United States)

    Liu, Wusheng; Stewart, C Neal

    2015-05-01

    Plant synthetic biology is an emerging field that combines engineering principles with plant biology toward the design and production of new devices. This emerging field should play an important role in future agriculture for traditional crop improvement, but also in enabling novel bioproduction in plants. In this review we discuss the design cycles of synthetic biology as well as key engineering principles, genetic parts, and computational tools that can be utilized in plant synthetic biology. Some pioneering examples are offered as a demonstration of how synthetic biology can be used to modify plants for specific purposes. These include synthetic sensors, synthetic metabolic pathways, and synthetic genomes. We also speculate about the future of synthetic biology of plants. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. Synthetic Cathinones ("Bath Salts")

    Science.gov (United States)

    ... Alcohol Club Drugs Cocaine Fentanyl Hallucinogens Inhalants Heroin Marijuana MDMA (Ecstasy/Molly) Methamphetamine Opioids Over-the-Counter Medicines Prescription Medicines Steroids (Anabolic) Synthetic Cannabinoids (K2/Spice) Synthetic Cathinones (Bath Salts) Tobacco/ ...

  11. Routed planar networks

    Directory of Open Access Journals (Sweden)

    David J. Aldous

    2016-04-01

    Full Text Available Modeling a road network as a planar graph seems very natural. However, in studying continuum limits of such networks it is useful to take {\\em routes} rather than {\\em edges} as primitives. This article is intended to introduce the relevant (discrete setting notion of {\\em routed network} to graph theorists. We give a naive classification of all 71 topologically different such networks on 4 leaves, and pose a variety of challenging research questions.

  12. Growth Modeling of Aspergillus niger Strains Isolated from Citrus Fruit as a Function of Temperature on a Synthetic Medium from Lime (Citrus latifolia T.) Pericarp.

    Science.gov (United States)

    Sandoval-Contreras, T; Marín, S; Villarruel-López, A; Gschaedler, A; Garrido-Sánchez, L; Ascencio, F

    2017-07-01

    Molds are responsible for postharvest spoilage of citrus fruits. The objective of this study was to evaluate the effect of temperature on growth rate and the time to visible growth of Aspergillus niger strains isolated from citrus fruits. The growth of these strains was studied on agar lime medium (AL) at different temperatures, and growth rate was estimated using the Baranyi and Roberts model (Int. J. Food Microbiol. 23:277-294, 1994). The Rosso et al. cardinal model with inflexion (L. Rosso, J. R. Lobry, S. Bajard, and J. P. Flandrois, J. Theor. Biol. 162:447-463, 1993) was used as a secondary model to describe the effect of temperature on growth rate and the lag phase. We hypothesized that the same model could be used to calculate the time for the mycelium to become visible (t v ) by substituting the lag phase (1/λ and 1/λ opt ) with the time to visible colony (1/t v -opt and 1/t v ), respectively, in the Rosso et al. High variability was observed at suboptimal conditions. Extremes of temperature of growth for A. niger seem to have a normal variability. For the growth rate and time t v , the model was satisfactorily compared with results of previous studies. An external validation was performed in lime fruits; the bias and accuracy factors were 1.3 and 1.5, respectively, for growth rate and 0.24 and 3.72, respectively, for the appearance time. The discrepancy may be due to the influence of external factors. A. niger grows significantly more slowly on lime fruit than in culture medium, probably because the nutrients are more easily available in medium than in fruits, where the peel consistency may be a physical barrier. These findings will help researchers understand the postharvest behavior of mold on lime fruits, host-pathogen interactions, and environmental conditions infecting fruit and also help them develop guidelines for future work in the field of predictive mycology to improve models for control of postharvest fungi.

  13. Collective network routing

    Science.gov (United States)

    Hoenicke, Dirk

    2014-12-02

    Disclosed are a unified method and apparatus to classify, route, and process injected data packets into a network so as to belong to a plurality of logical networks, each implementing a specific flow of data on top of a common physical network. The method allows to locally identify collectives of packets for local processing, such as the computation of the sum, difference, maximum, minimum, or other logical operations among the identified packet collective. Packets are injected together with a class-attribute and an opcode attribute. Network routers, employing the described method, use the packet attributes to look-up the class-specific route information from a local route table, which contains the local incoming and outgoing directions as part of the specifically implemented global data flow of the particular virtual network.

  14. Optimizing well intervention routes

    Energy Technology Data Exchange (ETDEWEB)

    Paiva, Ronaldo O. [PETROBRAS S.A., Vitoria, ES (Brazil); Schiozer, Denis J.; Bordalo, Sergio N. [Universidade Estadual de Campinas, SP (Brazil). Faculdade de Engenharia Mecanica. Centro de Estudo do Petroleo (CEPETRO)]. E-mail: denis@dep.fem.unicamp.br; bordalo@dep.fem.unicamp.br

    2000-07-01

    This work presents a method for optimizing the itinerary of work over rigs, i.e., the search for the route of minimum total cost, and demonstrates the importance of the dynamics of reservoir behaviour. The total cost of a route includes the rig expenses (transport, assembly and operation), which are functions of time and distances, plus the losses of revenue in wells waiting for the rig, which are also dependent of time. A reservoir simulator is used to evaluate the monetary influence of the well shutdown on the present value of the production curve. Finally, search algorithms are employed to determine the route of minimal cost. The Simulated Annealing algorithm was also successful in optimizing the distribution of a list of wells among different work over rigs. The rational approach presented here is recommended for management teams as a standard procedure to define the priority of wells scheduled for work over. (author)

  15. Synthetic-fuel production using Texas lignite and a very-high-temperature gas-cooled reactor for process heat and electrical power generation

    International Nuclear Information System (INIS)

    Ross, M.A.; Klein, D.E.

    1981-05-01

    This report presents two alternatives to increased reliance on foreign energy sources; each method utilizes the abundant domestic resources of coal, uranium, and thorium. Two approaches are studied in this report. First, the gasification and liquefaction of coal are accomplished with Lurgi gasifiers and Fischer-Tropsch synthesis. A 50,000 barrel per day facility, consuming 15 million tons of lignite coal per year, is used. Second, a nuclear-assisted coal conversion approach is studied using a very high temperature gas-cooled reactor with a modified Lurgi gasifier and Fischer-Tropsch synthesis. This is a preliminary report presenting background data and a means of comparison for the two approaches considered

  16. Multihop Wireless Networks Opportunistic Routing

    CERN Document Server

    Zeng, Kai; Li, Ming

    2011-01-01

    This book provides an introduction to opportunistic routing an emerging technology designed to improve the packet forwarding reliability, network capacity and energy efficiency of multihop wireless networks This book presents a comprehensive background to the technological challenges lying behind opportunistic routing. The authors cover many fundamental research issues for this new concept, including the basic principles, performance limit and performance improvement of opportunistic routing compared to traditional routing, energy efficiency and distributed opportunistic routing protocol desig

  17. INFLUENCE OF SILANE HEAT TREATMENT ON THE TENSILE BOND STRENGTH BETWEEN EX-3 SYNTHETIC VENEERING PORCELAIN AND COMPOSITE RESIN USING FIVE DIFFERENT ACTIVATION TEMPERATURES

    Directory of Open Access Journals (Sweden)

    Spartak Yanakiev

    2017-02-01

    Full Text Available Purpose: The purpose of the present study is to assess the effect of five different silane activation temperatures and eight activation methods on the tensile bond strength between one veneering porcelain and one composite resin material. Material and methods: A total of 81 ceramic rods were made of EX-3 veneering ceramic (Kuraray Noritake Dental, Japan. Sintered ceramic bars were grinded with diamond disks to size 10x2x2mm ± 0,05mm. The front part of each bar was polished. After ultrasonic cleaning in distilled water, the specimens were divided into nine groups. Silane was activated with air at room temperature, 38º С, 50º С, 100º С, 120º С using a custom made blow drier. In a silicone mold, a composite resin Z250 (3М ESPE, St. Paul, USA was condensed toward the bond ceramic surface. A total of 81 specimens approximately 2,0 cm long were prepared for tensile bond testing. One way ANOVA, followed by Bonferroni and Games-Howell tests were used for statistical analysis. Results: The lowest tensile bond strength was observed in the control group (3,51MPa. Group 2 yielded the highest bond strength among all groups (19,54MPa. Silane heat treatment enhanced the bond strength for all treatment methods. Within the polished specimens, the highest bond strength was yielded with warm air at 120ºС (11,31MPa. Conclusion: The most effective method for bonding Z250 composite resin to EX-3 veneering ceramic includes HF etching, silane, and adhesive resin. The most effective heat treatment method for bonding is hot air at 120ºС.

  18. Whirlpool routing for mobility

    KAUST Repository

    Lee, Jung Woo

    2010-01-01

    We present the Whirlpool Routing Protocol (WARP), which efficiently routes data to a node moving within a static mesh. The key insight in WARP\\'s design is that data traffic can use an existing routing gradient to efficiently probe the topology, repair the routing gradient, and communicate these repairs to nearby nodes. Using simulation, controlled testbeds, and real mobility experiments, we find that using the data plane for topology maintenance is highly effective due to the incremental nature of mobility updates. WARP leverages the fact that converging flows at a destination make the destination have the region of highest traffic. We provide a theoretical basis for WARP\\'s behavior, defining an "update area" in which the topology must adjust when a destination moves. As long as packets arrive at a destination before it moves outside of the update area, WARP can repair the topology using the data plane. Compared to existing protocols, such as DYMO and HYPER, WARP\\'s packet drop rate is up to 90% lower while sending up to 90% fewer packets.

  19. SET-Routes programme

    CERN Multimedia

    Marietta Schupp, EMBL Photolab

    2008-01-01

    Dr Sabine Hentze, specialist in human genetics, giving an Insight Lecture entitled "Human Genetics – Diagnostics, Indications and Ethical Issues" on 23 September 2008 at EMBL Heidelberg. Activities in a achool in Budapest during a visit of Angela Bekesi, Ambassadors for the SET-Routes programme.

  20. Evolvable synthetic neural system

    Science.gov (United States)

    Curtis, Steven A. (Inventor)

    2009-01-01

    An evolvable synthetic neural system includes an evolvable neural interface operably coupled to at least one neural basis function. Each neural basis function includes an evolvable neural interface operably coupled to a heuristic neural system to perform high-level functions and an autonomic neural system to perform low-level functions. In some embodiments, the evolvable synthetic neural system is operably coupled to one or more evolvable synthetic neural systems in a hierarchy.

  1. [From synthetic biology to synthetic humankind].

    Science.gov (United States)

    Nouvel, Pascal

    2015-01-01

    In this paper, we propose an historical survey of the expression "synthetic biology" in order to identify its main philosophical components. The result of the analysis is then used to investigate the meaning of the notion of "synthetic man". It is shown that both notions share a common philosophical background that can be summed up by the short but meaningful assertion: "biology is technology". The analysis allows us to distinguish two notions that are often confused in transhumanist literature: the notion of synthetic man and the notion of renewed man. The consequences of this crucial distinction are discussed. Copyright © 2015 Académie des sciences. Published by Elsevier SAS. All rights reserved.

  2. Designing synthetic biology.

    Science.gov (United States)

    Agapakis, Christina M

    2014-03-21

    Synthetic biology is frequently defined as the application of engineering design principles to biology. Such principles are intended to streamline the practice of biological engineering, to shorten the time required to design, build, and test synthetic gene networks. This streamlining of iterative design cycles can facilitate the future construction of biological systems for a range of applications in the production of fuels, foods, materials, and medicines. The promise of these potential applications as well as the emphasis on design has prompted critical reflection on synthetic biology from design theorists and practicing designers from many fields, who can bring valuable perspectives to the discipline. While interdisciplinary connections between biologists and engineers have built synthetic biology via the science and the technology of biology, interdisciplinary collaboration with artists, designers, and social theorists can provide insight on the connections between technology and society. Such collaborations can open up new avenues and new principles for research and design, as well as shed new light on the challenging context-dependence-both biological and social-that face living technologies at many scales. This review is inspired by the session titled "Design and Synthetic Biology: Connecting People and Technology" at Synthetic Biology 6.0 and covers a range of literature on design practice in synthetic biology and beyond. Critical engagement with how design is used to shape the discipline opens up new possibilities for how we might design the future of synthetic biology.

  3. British Dance: Black Routes

    OpenAIRE

    Adair, C.; Burt, Ramsay, 1953-

    2016-01-01

    British Dance: Black Routes re-examines the distinctive contributions made to British dance by dancers who are Black. Covering the period 1946 to the present, it presents a radical re-reading of dancers and their companies, placing their achievements within a broader historical, cultural and artistic context. The result of a two year research project, British Dance and the African Diaspora, led by editors Christy Adair and Ramsay Burt, the collection looks at artists working with contempor...

  4. Distinction of synthetic dl-α-tocopherol from natural vitamin E (d-α-tocopherol) by reversed-phase liquid chromatography. Enhanced selectivity of a polymeric C18 stationary phase at low temperature and/or at high pressure.

    Science.gov (United States)

    Yui, Yuko; Miyazaki, Shota; Ma, Yan; Ohira, Masayoshi; Fiehn, Oliver; Ikegami, Tohru; McCalley, David V; Tanaka, Nobuo

    2016-06-10

    Separation of diastereomers of dl-α-tocopherol was studied by reversed-phase liquid chromatography using three types of stationary phases, polymeric ODS, polymeric C30, and monomeric ODS. Polymeric ODS stationary phase (Inertsil ODS-P, 3mmID, 20cm) was effective for the separation of the isomers created by the presence of three chiral centers on the alkyl chain of synthetic dl-α-tocopherol. Considerable improvement of the separation of isomers was observed on ODS-P phase at high pressure and at low temperature. Complete separation of four pairs of diastereomers was achieved at 12.0°C, 536bar, while three peaks were observed when the separation was carried out either at 12.0°C at low pressure or at 20°C at 488bar. Higher temperature (30.0°C) with the ODS-P phase resulted in only partial separation of the diastereomers even at high pressure. Only slight resolution was observed for the mixture of diastereomers with the C30 stationary phase (Inertsil C30) at 12.0°C and 441bar, although the stationary phase afforded greater resolution for β- and γ-tocopherol than ODS-P. A monomeric C18 stationary phase did not show any separation at 12.0°C and 463bar. The results suggest that the binding site of the polymeric ODS-P phase is selective for flexible alkyl chains that provided the longest retention for the natural form, (R,R,R) form, and the enantiomer, (S,S,S) form, of dl-α-tocopherol. Copyright © 2016. Published by Elsevier B.V.

  5. Shape-Controlled Synthesis of CuO Nanocrystals by a Room Temperature Solid-Phase Route%室温固相合成形貌可控的CuO纳米晶及其表征

    Institute of Scientific and Technical Information of China (English)

    王文忠; 王丽娟

    2012-01-01

    通过室温固相反应法成功制备出具有一维棒状和球型状的CuO纳米晶.研究结果表明,在反应过程中,表面活性剂对CuO纳米晶的形貌起着决定性的作用.当反应过程在表面活性剂聚乙二醇400液态环境中进行时,所制备的CuO为一维棒状纳米晶.纳米棒的直径为6~14 nm、长度为100~400 nm;当反应过程在表面活性剂聚氧乙烯9醚液态环境中进行时,则所制备的CuO为球形纳米粒子,纳米粒子的直径为4~11nm,平均直径为7 nm.用X射线粉末衍射和透射显微镜技术对所制备纳米晶的成分、晶相、形状和尺寸进行了表征分析.对不同形貌CuO纳米晶的形成机理作了深入的讨论,提出了CuO纳米棒的表面活性剂软模板诱导自组装生长机理.%A room temperature solid-phase route has been developed for the synthesis of CuO nanocrystals with rod- and spherical-like morphology by using surfaetant as shape controller. The results indicate that the surfactant plays a key role in controlling the shape of CuO nanocrystals. The monoclinic phase CuO rod-like nanocrystals with diameter of 6 ~ 14 nm and length of 100 - 400 nm were successfully synthesized when the surfactant polyethylene glycol 400 was used as shape controller. If the surfactant nonylphenyl ether(9)was used as shape controller, keeping the other ecperimental conditions constant, the monoclinic phase CuO spherical nanocrystals with diameter of 4 - 11 nm and an average diameter of 7 nm were fabricated. XRD and TEM techniques were used to study on composition, phase, morphology and size of the as-prepaped CuO nanocrystals. The growth mechanism of CuO nanocrystals has been discussed in detail. A surfactant soft template induced self- assemble growth mechanism was proposed for the formation of Cuo nanorods.

  6. Designing synthetic RNA for delivery by nanoparticles

    International Nuclear Information System (INIS)

    Jedrzejczyk, Dominika; Pawlowska, Roza; Chworos, Arkadiusz; Gendaszewska-Darmach, Edyta

    2017-01-01

    The rapid development of synthetic biology and nanobiotechnology has led to the construction of various synthetic RNA nanoparticles of different functionalities and potential applications. As they occur naturally, nucleic acids are an attractive construction material for biocompatible nanoscaffold and nanomachine design. In this review, we provide an overview of the types of RNA and nucleic acid’s nanoparticle design, with the focus on relevant nanostructures utilized for gene-expression regulation in cellular models. Structural analysis and modeling is addressed along with the tools available for RNA structural prediction. The functionalization of RNA-based nanoparticles leading to prospective applications of such constructs in potential therapies is shown. The route from the nanoparticle design and modeling through synthesis and functionalization to cellular application is also described. For a better understanding of the fate of targeted RNA after delivery, an overview of RNA processing inside the cell is also provided. (topical review)

  7. Carbon monosulfide: a useful synthetic intermediate

    International Nuclear Information System (INIS)

    Kramer, M.P.

    1986-01-01

    The physical properties of carbon monosulfide, CS, are well documented. The molecule has been observed in interstellar space and is found to be a common intermediate in the thermal decomposition of carbon disulfide and other sulfur compounds. Interestingly enough, the chemistry of carbon monosulfide, a molecule that is isovalent with carbon monoxide, has received little attention. The explosive nature of the carbon monosulfide monomer, which hindered previous workers, was overcome by the development of special handling techniques. The ability to produce carbon monosulfide in gram quantities had lead to synthesis of novel compounds and to a more direct synthetic route for certain known compounds. Specifically, the following general reaction demonstrates the capabilities of carbon monosulfide on the synthetic scale. CS + RXY → RXC(S)Y;(X = N,S), (Y = H, Cl). Note: The initial product formed in the reaction can be an unstable intermediate

  8. Characterization of Thermal Stability of Synthetic and Semi-Synthetic Engine Oils

    Directory of Open Access Journals (Sweden)

    Anand Kumar Tripathi

    2015-03-01

    Full Text Available Engine oils undergo oxidative degradation and wears out during service. Hence it is important to characterize ageing of engine oils at different simulated conditions to evaluate the performance of existing oils and also design new formulations. This work focuses on characterizing the thermo-oxidative degradation of synthetic and semi-synthetic engine oils aged at 120, 149 and 200 °C. Apparent activation energy of decomposition of aged oils evaluated using the isoconversional Kissinger-Akahira-Sunose technique was used as a thermal stability marker. The temporal variation of stability at different ageing temperatures was corroborated with kinematic viscosity, oxidation, sulfation and nitration indices, total base number, antiwear additive content and molecular structure of the organic species present in the oils. At the lowest temperature employed, synthetic oil underwent higher rate of oxidation, while semi-synthetic oil was stable for longer time periods. At higher temperatures, the initial rate of change of average apparent activation energy of synthetic oil correlated well with a similar variation in oxidation number. A mixture of long chain linear, branched, and cyclic hydrocarbons were observed when semi-synthetic oil was degraded at higher temperatures.

  9. Research progress in synthetic technology of p-aminophenyl-β-sulfatoethylsulfone

    Directory of Open Access Journals (Sweden)

    Xue FENG

    2017-06-01

    Full Text Available The p-aminophenyl-β-sulfatoethylsulfone is one of the most important intermediates of vinyl-sulfone reactive dyes, and the demanded quantity increases gradually. The synthetic routes of p-aminophenyl-β-sulfatoethylsulfone using acetanilide, p-nitrochlorobenzene, etc. as raw materials are reviewed. The advantages and disadvantages and improved method of various kinds of synthetic routes are introduced, the objective evaluation is made for each synthetic route, and the esterification for synthesis of the intermediates of β-hydroxyethylsulfone esterification is analyzed. The prospect of p-aminophenyl-β-sulfatoethylsulfone is forecasted: Attaches great importance to the development of new routes, uses clean technology and new technology, develops the competitive products, speeds up the development of dye intermediates, and develops high value-added products.

  10. Robustness of airline route networks

    Science.gov (United States)

    Lordan, Oriol; Sallan, Jose M.; Escorihuela, Nuria; Gonzalez-Prieto, David

    2016-03-01

    Airlines shape their route network by defining their routes through supply and demand considerations, paying little attention to network performance indicators, such as network robustness. However, the collapse of an airline network can produce high financial costs for the airline and all its geographical area of influence. The aim of this study is to analyze the topology and robustness of the network route of airlines following Low Cost Carriers (LCCs) and Full Service Carriers (FSCs) business models. Results show that FSC hubs are more central than LCC bases in their route network. As a result, LCC route networks are more robust than FSC networks.

  11. Synthetic Defects for Vibrothermography

    Science.gov (United States)

    Renshaw, Jeremy; Holland, Stephen D.; Thompson, R. Bruce; Eisenmann, David J.

    2010-02-01

    Synthetic defects are an important tool used for characterizing the performance of nondestructive evaluation techniques. Viscous material-filled synthetic defects were developed for use in vibrothermography (also known as sonic IR) as a tool to improve inspection accuracy and reliability. This paper describes how the heat-generation response of these VMF synthetic defects is similar to the response of real defects. It also shows how VMF defects can be applied to improve inspection accuracy for complex industrial parts and presents a study of their application in an aircraft engine stator vane.

  12. Synthetic biological networks

    International Nuclear Information System (INIS)

    Archer, Eric; Süel, Gürol M

    2013-01-01

    Despite their obvious relationship and overlap, the field of physics is blessed with many insightful laws, while such laws are sadly absent in biology. Here we aim to discuss how the rise of a more recent field known as synthetic biology may allow us to more directly test hypotheses regarding the possible design principles of natural biological networks and systems. In particular, this review focuses on synthetic gene regulatory networks engineered to perform specific functions or exhibit particular dynamic behaviors. Advances in synthetic biology may set the stage to uncover the relationship of potential biological principles to those developed in physics. (review article)

  13. Personal continuous route pattern mining

    Institute of Scientific and Technical Information of China (English)

    Qian YE; Ling CHEN; Gen-cai CHEN

    2009-01-01

    In the daily life, people often repeat regular routes in certain periods. In this paper, a mining system is developed to find the continuous route patterns of personal past trips. In order to count the diversity of personal moving status, the mining system employs the adaptive GPS data recording and five data filters to guarantee the clean trips data. The mining system uses a client/server architecture to protect personal privacy and to reduce the computational load. The server conducts the main mining procedure but with insufficient information to recover real personal routes. In order to improve the scalability of sequential pattern mining, a novel pattern mining algorithm, continuous route pattern mining (CRPM), is proposed. This algorithm can tolerate the different disturbances in real routes and extract the frequent patterns. Experimental results based on nine persons' trips show that CRPM can extract more than two times longer route patterns than the traditional route pattern mining algorithms.

  14. Elisabeth Badinter, Fausse route

    OpenAIRE

    Martin-Juchat, Fabienne

    2013-01-01

    Elisabeth Badinter, philosophe de formation, est l’auteure de nombreux ouvrages sur la condition féminine et les rapports hommes/femmes dans la société. Avec Fausse route, elle signe une vision polémique du féminisme occidental. Son ouvrage a suscité de nombreuses critiques de femmes dans diverses revues destinées au grand public. Hélène Strohl, recenseur de la revue Culture en mouvement, conclut que cet ouvrage est peu scientifique, sujet à caution : « Argument contre argument, amalgame cont...

  15. Models for synthetic biology.

    Science.gov (United States)

    Kaznessis, Yiannis N

    2007-11-06

    Synthetic biological engineering is emerging from biology as a distinct discipline based on quantification. The technologies propelling synthetic biology are not new, nor is the concept of designing novel biological molecules. What is new is the emphasis on system behavior. The objective is the design and construction of new biological devices and systems to deliver useful applications. Numerous synthetic gene circuits have been created in the past decade, including bistable switches, oscillators, and logic gates, and possible applications abound, including biofuels, detectors for biochemical and chemical weapons, disease diagnosis, and gene therapies. More than fifty years after the discovery of the molecular structure of DNA, molecular biology is mature enough for real quantification that is useful for biological engineering applications, similar to the revolution in modeling in chemistry in the 1950s. With the excitement that synthetic biology is generating, the engineering and biological science communities appear remarkably willing to cross disciplinary boundaries toward a common goal.

  16. Technical Assessment: Synthetic Biology

    Science.gov (United States)

    2015-01-01

    Pfizer, Bausch & Lomb, Coca - Cola , and other Fortune 500 companies 8 Data estimated by the... financial prize for ideas to drive forward the production of a sensor relying on synthetic organisms that can detect exposure to 500 specific chemicals

  17. Routing Service Quality—Local Driver Behavior Versus Routing Services

    DEFF Research Database (Denmark)

    Ceikute, Vaida; Jensen, Christian S.

    2013-01-01

    of the quality of one kind of location-based service, namely routing services. Specifically, the paper presents a framework that enables the comparison of the routes provided by routing services with the actual driving behaviors of local drivers. Comparisons include route length, travel time, and also route...... popularity, which are enabled by common driving behaviors found in available trajectory data. The ability to evaluate the quality of routing services enables service providers to improve the quality of their services and enables users to identify the services that best serve their needs. The paper covers......Mobile location-based services is a very successful class of services that are being used frequently by users with GPS-enabled mobile devices such as smartphones. This paper presents a study of how to exploit GPS trajectory data, which is available in increasing volumes, for the assessment...

  18. SCScore: Synthetic Complexity Learned from a Reaction Corpus.

    Science.gov (United States)

    Coley, Connor W; Rogers, Luke; Green, William H; Jensen, Klavs F

    2018-02-26

    Several definitions of molecular complexity exist to facilitate prioritization of lead compounds, to identify diversity-inducing and complexifying reactions, and to guide retrosynthetic searches. In this work, we focus on synthetic complexity and reformalize its definition to correlate with the expected number of reaction steps required to produce a target molecule, with implicit knowledge about what compounds are reasonable starting materials. We train a neural network model on 12 million reactions from the Reaxys database to impose a pairwise inequality constraint enforcing the premise of this definition: that on average, the products of published chemical reactions should be more synthetically complex than their corresponding reactants. The learned metric (SCScore) exhibits highly desirable nonlinear behavior, particularly in recognizing increases in synthetic complexity throughout a number of linear synthetic routes.

  19. Influence of Route-R on wrought magnesium AZ61 alloy mechanical properties through equal channel angular pressing

    Directory of Open Access Journals (Sweden)

    Muralidhar Avvari

    2014-06-01

    Full Text Available A new fundamental route entitled ‘Route-R’ is introduced to refine the grains in the material through Equal Channel Angular Pressing (ECAP process. In route R, specimen is inverted to the original position in each ECAP pass. In the present work, AZ61 alloy is processed using ECAP process for three different fundamental routes mainly route A, route Bc, and route R. ECAP experiment is carried out on AZ61 alloy at lower temperature of 483 K up to two passes. Microstructural characterization is evaluated on unECAPed and ECAPed specimens for three routes. Average grain size of the alloy is to be reduced from 66 μm to 16 μm, 14.1 μm and 10 μm for route A routes Bc, and route R respectively. Vickers microhardness of the alloy is found to be 60 HV for as received material. This microhardness of the alloy is increased to 71 HV, 72 HV, and 74 HV for route A, route Bc, and route R respectively. Mechanical properties of the AZ61 alloy are observed to be route R is providing maximum YS, UTS, and percentage elongation than other route A and route Bc. Tensile fracture topography of the specimen is analyzed using three different routes for two passes.

  20. An overview of smart grid routing algorithms

    Science.gov (United States)

    Wang, Junsheng; OU, Qinghai; Shen, Haijuan

    2017-08-01

    This paper summarizes the typical routing algorithm in smart grid by analyzing the communication business and communication requirements of intelligent grid. Mainly from the two kinds of routing algorithm is analyzed, namely clustering routing algorithm and routing algorithm, analyzed the advantages and disadvantages of two kinds of typical routing algorithm in routing algorithm and applicability.

  1. Water-oxidation catalysis by synthetic manganese oxides--systematic variations of the calcium birnessite theme.

    Science.gov (United States)

    Frey, Carolin E; Wiechen, Mathias; Kurz, Philipp

    2014-03-21

    Layered manganese oxides from the birnessite mineral family have been identified as promising heterogeneous compounds for water-oxidation catalysis (WOC), a key reaction for the conversion of renewable energy into storable fuels. High catalytic rates were especially observed for birnessites which contain calcium as part of their structures. With the aim to systematically improve the catalytic performance of such oxide materials, we used a flexible synthetic route to prepare three series of calcium birnessites, where we varied the calcium concentrations, the ripening times of the original precipitates and the temperature of the heat treatment following the initial synthetic steps (tempering) during the preparation process. The products were carefully analysed by a number of analytical techniques and then probed for WOC activity using the Ce(4+)-system. We find that our set of twenty closely related manganese oxides shows large, but somewhat systematic alterations in catalytic rates, indicating the importance of synthesis parameters for maximum catalytic performance. The catalyst of the series for which the highest water-oxidation rate was found is a birnessite of medium calcium content (Ca : Mn ratio 0.2 : 1) that had been subjected to a tempering temperature of 400 °C. On the basis of the detailed analysis of the results, a WOC reaction scheme for birnessites is proposed to explain the observed trends in reactivity.

  2. Morphological and magnetic properties of sol-gel synthetized meso and macroporous spheres of barium hexaferrite (BaFe{sub 12}O{sub 19})

    Energy Technology Data Exchange (ETDEWEB)

    Torres-Cadenas, S., E-mail: storres_c@hotmail.com [Instituto de Investigaciones Metalúrgicas y Materiales, UMSNH, Edificio U, Ciudad Universitaria, Santiago Tapia 403, Colonia Centro, 58030 Morelia (Mexico); Reyes-Gasga, José, E-mail: jreyes@fisica.unam.mx [Instituto de Física, UNAM, Circuito de la Investigación s/n, Ciudad Universitaria, 04510 Coyoacán, México, D.F. (Mexico); Bravo-Patiño, A., E-mail: brapal@hotmail.com [Centro Multidisciplinario de Estudios en Biotecnología (CMEB) de la FMVZ, UMSNH, Posta Zootécnica, km. 8.5 carretera Morelia-Zinapecuaro, C.P. 58890 col. La Palma, Tarimbaro, Michoacán (Mexico); Betancourt, I., E-mail: israelb@iim.unam.mx [Instituto de Investigaciones en Materiales, UNAM, Ciudad de México C.P. 04510 (Mexico); Contreras-García, M.E., E-mail: eucontre@gmail.com [Instituto de Investigaciones Metalúrgicas y Materiales, UMSNH, Edificio U, Ciudad Universitaria, Santiago Tapia 403, Colonia Centro, 58030 Morelia (Mexico)

    2017-06-15

    Highlights: • 1.5 µm porous spheres of BaFe{sub 12}O{sub 19} were synthetized by the sol-gel method. • Surfactant Tween20 (C{sub 58}H{sub 114}O{sub 26}) enabled the creation of the mesoporous structure. • Polystyrene spheres (PS) were used as the template for the formation of macropores. • Spheres resembled a nest or ball-of-yarn type of elongated BaFe{sub 12}O{sub 19} crystals. • Magnetic properties are evaluated as function of the calcination temperature. - Abstract: Porous spherical aggregates of barium hexaferrite (BaFe{sub 12}O{sub 19}) with 1.5 µm in diameter were synthetized by the surfactant-assisted sol-gel method. The surfactant Tween20 (C{sub 58}H{sub 114}O{sub 26}), which enables mesoporous structures, as well as polystyrene spheres (PS), as the template agent for the formation of macropores, were used. Two synthetic routes (hereafter named A and B), whose difference was the absence or presence of PS, were followed for synthesis. X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) in high resolution mode (HRTEM) were used for characterization. Size and morphology of the spheres were similar in both cases and they resemble a nest or ball-of-yarn type structure. Pore size and BaFe{sub 12}O{sub 19} crystal size produced by the two routes are different. The magnetic properties of the spheres were evaluated using a vibrating sample magnetometer (VSM) as function of the calcination temperature. The spheres present ferromagnetic behavior in both routes.

  3. Morphological and magnetic properties of sol-gel synthetized meso and macroporous spheres of barium hexaferrite (BaFe12O19)

    International Nuclear Information System (INIS)

    Torres-Cadenas, S.; Reyes-Gasga, José; Bravo-Patiño, A.; Betancourt, I.; Contreras-García, M.E.

    2017-01-01

    Highlights: • 1.5 µm porous spheres of BaFe 12 O 19 were synthetized by the sol-gel method. • Surfactant Tween20 (C 58 H 114 O 26 ) enabled the creation of the mesoporous structure. • Polystyrene spheres (PS) were used as the template for the formation of macropores. • Spheres resembled a nest or ball-of-yarn type of elongated BaFe 12 O 19 crystals. • Magnetic properties are evaluated as function of the calcination temperature. - Abstract: Porous spherical aggregates of barium hexaferrite (BaFe 12 O 19 ) with 1.5 µm in diameter were synthetized by the surfactant-assisted sol-gel method. The surfactant Tween20 (C 58 H 114 O 26 ), which enables mesoporous structures, as well as polystyrene spheres (PS), as the template agent for the formation of macropores, were used. Two synthetic routes (hereafter named A and B), whose difference was the absence or presence of PS, were followed for synthesis. X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) in high resolution mode (HRTEM) were used for characterization. Size and morphology of the spheres were similar in both cases and they resemble a nest or ball-of-yarn type structure. Pore size and BaFe 12 O 19 crystal size produced by the two routes are different. The magnetic properties of the spheres were evaluated using a vibrating sample magnetometer (VSM) as function of the calcination temperature. The spheres present ferromagnetic behavior in both routes.

  4. Vertex routing models

    International Nuclear Information System (INIS)

    Markovic, D; Gros, C

    2009-01-01

    A class of models describing the flow of information within networks via routing processes is proposed and investigated, concentrating on the effects of memory traces on the global properties. The long-term flow of information is governed by cyclic attractors, allowing to define a measure for the information centrality of a vertex given by the number of attractors passing through this vertex. We find the number of vertices having a nonzero information centrality to be extensive/subextensive for models with/without a memory trace in the thermodynamic limit. We evaluate the distribution of the number of cycles, of the cycle length and of the maximal basins of attraction, finding a complete scaling collapse in the thermodynamic limit for the latter. Possible implications of our results for the information flow in social networks are discussed.

  5. Southern states' routing agency report

    International Nuclear Information System (INIS)

    1989-02-01

    The Southern states' routing agency report is a compendium of 16-southern states' routing programs relative to the transportation of high-level radioactive materials. The report identifies the state-designated routing agencies as defined under 49 Code of Federal Regulations (CFR) Part 171 and provides a reference to the source ad scope of the agencies' rulemaking authority. Additionally, the state agency and contact designated by the state's governor to receive advance notification and shipment routing information under 10 CFR Parts 71 and 73 are also listed

  6. Southern States' Routing Agency Report

    International Nuclear Information System (INIS)

    1990-03-01

    The Southern States' Routing Agency Report is a compendium of 16-southern states' routing program for the transportation of high-level radioactive materials. The report identifies the state-designated routing agencies as defined under 49 Code of Federal Regulations (CFR) Part 171 and provides a reference to the source and scope of the agencies' rulemaking authority. Additionally, the state agency and contact designated by the state's governor to receive advance notification and shipment routing information under 10 CFR Parts 71 and 73 are also listed

  7. Synthetic biology for microbial production of lipid-based biofuels.

    Science.gov (United States)

    d'Espaux, Leo; Mendez-Perez, Daniel; Li, Rachel; Keasling, Jay D

    2015-12-01

    The risks of maintaining current CO2 emission trends have led to interest in producing biofuels using engineered microbes. Microbial biofuels reduce emissions because CO2 produced by fuel combustion is offset by CO2 captured by growing biomass, which is later used as feedstock for biofuel fermentation. Hydrocarbons found in petroleum fuels share striking similarity with biological lipids. Here we review synthetic metabolic pathways based on fatty acid and isoprenoid metabolism to produce alkanes and other molecules suitable as biofuels. We further discuss engineering strategies to optimize engineered biosynthetic routes, as well as the potential of synthetic biology for sustainable manufacturing. Published by Elsevier Ltd.

  8. Synthetic biology for microbial production of lipid-based biofuels

    Energy Technology Data Exchange (ETDEWEB)

    d' Espaux, L; Mendez-Perez, D; Li, R; Keasling, JD

    2015-10-23

    The risks of maintaining current CO2 emission trends have led to interest in producing biofuels using engineered microbes. Microbial biofuels reduce emissions because CO2 produced by fuel combustion is offset by CO2 captured by growing biomass, which is later used as feedstock for biofuel fermentation. Hydrocarbons found in petroleum fuels share striking similarity with biological lipids. Here in this paper we review synthetic metabolic pathways based on fatty acid and isoprenoid metabolism to produce alkanes and other molecules suitable as biofuels. Lastly, we further discuss engineering strategies to optimize engineered biosynthetic routes, as well as the potential of synthetic biology for sustainable manufacturing.

  9. Stochastic vehicle routing with recourse

    DEFF Research Database (Denmark)

    Gørtz, Inge Li; Nagarajan, Viswanath; Saket, Rishi

    2012-01-01

    instantiations, a recourse route is computed - but costs here become more expensive by a factor λ. We present an O(log2n ·log(nλ))-approximation algorithm for this stochastic routing problem, under arbitrary distributions. The main idea in this result is relating StochVRP to a special case of submodular...

  10. Route-external and route-internal landmarks in route descriptions : Effects of route length and map design

    NARCIS (Netherlands)

    Westerbeek, Hans; Maes, Alfons

    2013-01-01

    Landmarks are basic ingredients in route descriptions. They often mark choice points: locations where travellers choose from different options how to continue the route. This study focuses on one of the loose ends in the taxonomy of landmarks. In a memory-based production experiment in which

  11. Perception bias in route choice

    NARCIS (Netherlands)

    Vreeswijk, Jacob Dirk; Thomas, Tom; van Berkum, Eric C.; van Arem, Bart

    2014-01-01

    Travel time is probably one of the most studied attributes in route choice. Recently, perception of travel time received more attention as several studies have shown its importance in explaining route choice behavior. In particular, travel time estimates by travelers appear to be biased against

  12. Semi-synthetic preparation of the rare, cytotoxic, deep-sea sourced sponge metabolites discorhabdins P and U.

    Science.gov (United States)

    Grkovic, Tanja; Kaur, Balwinder; Webb, Victoria L; Copp, Brent R

    2006-04-01

    Semi-synthetic routes to the enzyme inhibitory and potently anti-proliferative marine natural products discorhabdins P and U were developed by one-step methylation reactions of discorhabdins C and B, respectively. Two novel semi-synthetic derivatives of discorhabdin U were also prepared, one of which (6) exhibited significant anti-proliferative activity.

  13. What Are Synthetic Cannabinoids?

    Science.gov (United States)

    ... years, synthetic cannabinoid mixtures have been easy to buy in drug paraphernalia shops, novelty stores, gas stations, and over ... abuse, authorities have made it illegal to sell, buy, or possess some of ... use is that standard drug tests cannot easily detect many of the chemicals ...

  14. Synthetic Aperture Sequential Beamforming

    DEFF Research Database (Denmark)

    Kortbek, Jacob; Jensen, Jørgen Arendt; Gammelmark, Kim Løkke

    2008-01-01

    A synthetic aperture focusing (SAF) technique denoted Synthetic Aperture Sequential Beamforming (SASB) suitable for 2D and 3D imaging is presented. The technique differ from prior art of SAF in the sense that SAF is performed on pre-beamformed data contrary to channel data. The objective is to im......A synthetic aperture focusing (SAF) technique denoted Synthetic Aperture Sequential Beamforming (SASB) suitable for 2D and 3D imaging is presented. The technique differ from prior art of SAF in the sense that SAF is performed on pre-beamformed data contrary to channel data. The objective...... is to improve and obtain a more range independent lateral resolution compared to conventional dynamic receive focusing (DRF) without compromising frame rate. SASB is a two-stage procedure using two separate beamformers. First a set of Bmode image lines using a single focal point in both transmit and receive...... is stored. The second stage applies the focused image lines from the first stage as input data. The SASB method has been investigated using simulations in Field II and by off-line processing of data acquired with a commercial scanner. The performance of SASB with a static image object is compared with DRF...

  15. Building synthetic cellular organization

    OpenAIRE

    Polka, Jessica K.; Silver, Pamela A.

    2013-01-01

    The elaborate spatial organization of cells enhances, restricts, and regulates protein–protein interactions. However, the biological significance of this organization has been difficult to study without ways of directly perturbing it. We highlight synthetic biology tools for engineering novel cellular organization, describing how they have been, and can be, used to advance cell biology.

  16. Towards a synthetic chloroplast.

    Directory of Open Access Journals (Sweden)

    Christina M Agapakis

    2011-04-01

    Full Text Available The evolution of eukaryotic cells is widely agreed to have proceeded through a series of endosymbiotic events between larger cells and proteobacteria or cyanobacteria, leading to the formation of mitochondria or chloroplasts, respectively. Engineered endosymbiotic relationships between different species of cells are a valuable tool for synthetic biology, where engineered pathways based on two species could take advantage of the unique abilities of each mutualistic partner.We explored the possibility of using the photosynthetic bacterium Synechococcus elongatus PCC 7942 as a platform for studying evolutionary dynamics and for designing two-species synthetic biological systems. We observed that the cyanobacteria were relatively harmless to eukaryotic host cells compared to Escherichia coli when injected into the embryos of zebrafish, Danio rerio, or taken up by mammalian macrophages. In addition, when engineered with invasin from Yersinia pestis and listeriolysin O from Listeria monocytogenes, S. elongatus was able to invade cultured mammalian cells and divide inside macrophages.Our results show that it is possible to engineer photosynthetic bacteria to invade the cytoplasm of mammalian cells for further engineering and applications in synthetic biology. Engineered invasive but non-pathogenic or immunogenic photosynthetic bacteria have great potential as synthetic biological devices.

  17. Synthetic Metabolic Pathways

    DEFF Research Database (Denmark)

    topics, lists of the necessary materials and reagents, step-by-step, readily reproducible laboratory protocols, and tips on troubleshooting and avoiding known pitfalls. Authoritative and practical, Synthetic Metabolic Pathways: Methods and Protocols aims to ensure successful results in the further study...

  18. Facile and solvent-free routes for the synthesis of size-controllable Fe3O4 nanoparticles

    International Nuclear Information System (INIS)

    Ngo, Thanh Hieu; Tran, Dai Lam; Do, Hung Manh; Le, Van Hong; Nguyen, Xuan Phuc; Tran, Vinh Hoang

    2010-01-01

    Magnetite nanoparticles are one of the most important materials that are widely used in both medically diagnostic and therapeutic research. In this paper, we present some facile and non-toxic synthetic approaches for size-controllable preparations of magnetite nanoparticles, which are appropriate for biomedical applications, namely (i) co-precipitation; (ii) reduction–precipitation and (iii) oxidation–precipitation. Magnetic characterizations of the obtained nanoparticles have been studied and discussed. The oxidation precipitation route was chosen for investigation of the dependence of kinetic driven activation energy and that of coercive force on particle size (and temperature) during the course of the reaction. The structural–magnetic behavior was also correlated. Being solvent and surfactant-free, these methods are advantageous for synthesis and further functionalization towards biomedical applications

  19. Synthetic Approaches to the Lamellarins—A Comprehensive Review

    Directory of Open Access Journals (Sweden)

    Dennis Imbri

    2014-12-01

    Full Text Available The present review discusses the known synthetic routes to the lamellarin alkaloids published until 2014. It begins with syntheses of the structurally simpler type-II lamellarins and then focuses on the larger class of the 5,6-saturated and -unsaturated type-I lamellarins. The syntheses are grouped by the strategy employed for the assembly of the central pyrrole ring.

  20. Rheological characteristics of synthetic road binders

    Energy Technology Data Exchange (ETDEWEB)

    Gordon D. Airey; Musarrat H. Mohammed; Caroline Fichter [University of Nottingham, Nottingham (United Kingdom)

    2008-08-15

    This paper deals with the synthesis of polymer binders from monomers that could in future be derived from renewable resources. These binders consist of polyethyl acrylate (PEA) of different molecular weight, polymethyl acrylate (PMA) and polybutyl acrylate (PBA), which were synthesised from ethyl acrylate, methyl acrylate and butyl acrylate, respectively, by atom transfer radical polymerization (ATRP). The fundamental rheological properties of these binders were determined by means of a dynamic shear rheometer (DSR) using a combination of temperature and frequency sweeps. The results indicate that PEA has rheological properties similar to that of 100/150 penetration grade bitumen, PMA similar rheological properties to that of 10/20 penetration grade bitumen, while PBA, due to its highly viscous nature and low complex modulus, cannot be used on its own as an asphalt binder. The synthetic binders were also combined with conventional penetration grade bitumen to produce a range of bitumen-synthetic polymer binder blends. These blends were batched by mass in the ratio of 1:1 or 3:1 and subjected to the same DSR rheological testing as the synthetic binders. The blends consisting of a softer bitumen (70/100 pen or 100/150 pen) with a hard synthetic binder (PMA) tended to be more compatible and therefore stable and produced rheological properties that combined the properties of the two components. The synthetic binders and particularly the extended bitumen samples (blends) produced rheological properties that showed similar characteristics to elastomeric SBS PMBs. 30 refs., 12 figs., 2 tabs.

  1. Preparation of synthetic standard minerals

    International Nuclear Information System (INIS)

    Herrick, C.C.; Bustamante, S.J.; Charls, R.W.; Cowan, R.E.; Hakkila, E.A.; Hull, D.E.; Olinger, B.W.; Roof, R.B.; Sheinberg, H.; Herrick, G.C.

    1978-01-01

    A number of techniques for synthetic mineral preparations have been examined. These techniques include hot-pressing in graphite dies at moderate pressures, high-pressure, high-temperature synthesis in a piston and cylinder apparatus, isostatic pressing under helium gas pressures, hydrous mineral preparations using water as the pressure medium, explosion-generated shock waves, and radiofrequency heating. Minerals suitable for equation-of-state studies (three-inch, high-density discs), for thermodynamic property determinations (low-density powders) and for microprobe standards (fusion-cast microbeads) have been prepared. Mechanical stress-strain calculations in the piston-cylinder apparatus have been initiated and their integration with thermal stress calculations is currently under investigation

  2. Road Routes for Waste Disposal - MDC_RecyclingRoute

    Data.gov (United States)

    NSGIC Local Govt | GIS Inventory — This CURBSIDE RECYCLING ROUTES BOUNDARIES LAYER IS A polygon feature class created for the Miami-Dade Department of Solid Waste Management (DSWM). It contains the...

  3. Capacity Constrained Routing Algorithms for Evacuation Route Planning

    National Research Council Canada - National Science Library

    Lu, Qingsong; George, Betsy; Shekhar, Shashi

    2006-01-01

    .... In this paper, we propose a new approach, namely a capacity constrained routing planner which models capacity as a time series and generalizes shortest path algorithms to incorporate capacity constraints...

  4. Pheromone based alternative route planning

    Directory of Open Access Journals (Sweden)

    Liangbing Feng

    2016-08-01

    Full Text Available In this work, we propose an improved alternative route calculation based on alternative figures, which is suitable for practical environments. The improvement is based on the fact that the main traffic route is the road network skeleton in a city. Our approach using nodes may generate a higher possibility of overlapping. We employ a bidirectional Dijkstra algorithm to search the route. To measure the quality of an Alternative Figures (AG, three quotas are proposed. The experiment results indicate that the improved algorithm proposed in this paper is more effective than others.

  5. Route planning algorithms: Planific@ Project

    Directory of Open Access Journals (Sweden)

    Gonzalo Martín Ortega

    2009-12-01

    Full Text Available Planific@ is a route planning project for the city of Madrid (Spain. Its main aim is to develop an intelligence system capable of routing people from one place in the city to any other using the public transport. In order to do this, it is necessary to take into account such things as: time, traffic, user preferences, etc. Before beginning to design the project is necessary to make a comprehensive study of the variety of main known route planning algorithms suitable to be used in this project.

  6. Port Authority of Allegheny County Transit Routes

    Data.gov (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — Shapefile of Transit Routes - Please refer to each resource for active dates of the route information. Routes change over time,

  7. Synthetic Electric Microbial Biosensors

    Science.gov (United States)

    2017-06-10

    domains and DNA-binding domains into a single protein for deregulation of down stream genes of have been favored [10]. Initially experiments with... Germany DISTRIBUTION A. Approved for public release: distribution unlimited.   Talk title: “Synthetic biology based microbial biosensors for the...toolbox” in Heidelberg, Germany Poster title: “Anaerobic whole cell microbial biosensors” Link: http://phdsymposium.embl.org/#home   September, 2014

  8. The Bio-accessibility of Synthetic Fe-Organo Complexes in Subsurface Soil with Elevated Temperature: a Proxy for the Vulnerability of Mineral Associated Carbon to Warming Rachel C. Porras, Peter S. Nico, and Margaret Torn Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA

    Science.gov (United States)

    Porras, R. C.; Hicks Pries, C.

    2015-12-01

    Globally, subsurface soils (>30 cm) represent an important reservoir of soil organic carbon (SOC). However, the vulnerability of this deep SOC and, in particular mineral-associated SOC, to warming, and its potential to amplify the effects of climate change is highly uncertain. To gain insight into the bio-accessibility and temperature sensitivity of mineral-associated organic C, we conducted a series of incubations using soils collected from three depths (0-10, 50-60, and 80-90 cm) under coniferous forest. The soils are moderately acidic (mean pH=6.5) sandy, mixed, mesic Ultic Haploxeralfs. To understand how mechanisms controlling SOC bio-accessibilty or temperature sensitivity differ with depth and with the properties of Fe-organo complexes (i.e.,degree of crystallinity, amount of reactive surface area, or surface saturation), we used a 13C labeled glucose substrate to prepare synthetic Fe-organo complexes spanning a range of crystallinity and mineral surface saturation. The synthetic Fe-organo complexes were then added to soil from three depths. The soils containing the 13C labeled Fe-organo adduct were incubated at two temperatures (ambient and +4°C) and respired 13CO2 was measured and used to estimate flux rates. Differences in measured 13CO2 fluxes as a function of depth, surface loading, and mineral properties are discussed in terms of their implications for the temperature sensitivity of mineral protected organic carbon in subsurface soils.

  9. Catalytic acetoxylation of lactic acid to 2-acetoxypropionic acid, en route to acrylic acid

    NARCIS (Netherlands)

    Beerthuis, R.; Granollers, M.; Brown, D.R.; Salavagione, H.J.; Rothenberg, G.; Shiju, N.R.

    2015-01-01

    We present an alternative synthetic route to acrylic acid, starting from the platform chemical lactic acid and using heterogeneous catalysis. To improve selectivity, we designed an indirect dehydration reaction that proceeds via acetoxylation of lactic acid to 2-acetoxypropionic acid. This

  10. VT Route Log Points 2017

    Data.gov (United States)

    Vermont Center for Geographic Information — This data layer is used with VTrans' Integrated Route Log System (IRA). It is also used to calibrate the linear referencing systems, including the End-to-End and...

  11. Predicting Catastrophic BGP Routing Instabilities

    National Research Council Canada - National Science Library

    Nguyen, Lien

    2004-01-01

    .... Currently, this critical function is performed by the Border Gateway Protocol (BGP) version 4 RF01771. Like all routing protocols, BGP is vulnerable to instabilities that reduce its effectiveness...

  12. New TPG bus route 28

    CERN Multimedia

    2003-01-01

    Geneva's Public Transport services (TPG) have recently inaugurated a new bus line 28, connecting the La Tour Hospital in Meyrin to the international organisations in Geneva, via the airport. All signs associated with this route will be yellow in colour. Timetables and route details can be found at http://www.tpg.ch. Relations with the Host States Service http://www.cern.ch/relations/ Tel. 72848

  13. Fusion as a source of synthetic fuels

    International Nuclear Information System (INIS)

    Powell, J.R.; Fillo, J.A.; Steinberg, M.

    1981-01-01

    In the near-term, coal derived synthetic fuels will be used; but in the long-term, resource depletion and environmental effects will mandate synthetic fuels from inexhaustible sources - fission, fusion, and solar. Of the three sources, fusion appears uniquely suited for the efficient production of hydrogen-based fuels, due to its ability to directly generate very high process temperatures (up to approx. 2000 0 C) for water splitting reactions. Fusion-based water splitting reactions include high temperature electrolysis (HTE) of steam, thermochemical cycles, hybrid electrochemical/thermochemical, and direct thermal decomposition. HTE appears to be the simplest and most efficient process with efficiencies of 50 to 70% (fusion to hydrogen chemical energy), depending on process conditions

  14. Opportunities in plant synthetic biology.

    Science.gov (United States)

    Cook, Charis; Martin, Lisa; Bastow, Ruth

    2014-05-01

    Synthetic biology is an emerging field uniting scientists from all disciplines with the aim of designing or re-designing biological processes. Initially, synthetic biology breakthroughs came from microbiology, chemistry, physics, computer science, materials science, mathematics, and engineering disciplines. A transition to multicellular systems is the next logical step for synthetic biologists and plants will provide an ideal platform for this new phase of research. This meeting report highlights some of the exciting plant synthetic biology projects, and tools and resources, presented and discussed at the 2013 GARNet workshop on plant synthetic biology.

  15. Growth and optical spectroscopy of synthetic diamonds

    International Nuclear Information System (INIS)

    Mudryj, A.V.; Larionova, T.P.; Shakin, I.A.; Gysakov, G.A.; Dubrov, G.A.; Tikhonov, V.V.

    2003-01-01

    It is studied the growth and optical properties of synthetic diamonds, which may be used for detection of ionizing radiation, optical windows, heat removal, ultraviolet and thermo sensors, optoelectronic devices. Optical properties of diamonds (grown in different technological conditions) were studied in temperature range 78 - 300 K by means of measuring transmission in spectral band 0.2 - 25 μm, photoluminescence and registration of luminescence excitation spectra in spectral band 0.2 - 2 μm

  16. Routing-based synthesis of digital microfluidic biochips

    DEFF Research Database (Denmark)

    Maftei, Elena; Pop, Paul; Madsen, Jan

    2012-01-01

    Microfluidic biochips are replacing the conventional biochemical analyzers, and are able to integrate on-chip all the necessary functions for biochemical analysis. The “digital” biochips are manipulating liquids as discrete droplets on a two-dimensional array of electrodes. Basic microfluidic...... electrodes are considered occupied during the operation execution, although the droplet uses only one electrode at a time. Moreover, the operations can actually be performed by routing the droplets on any sequence of electrodes on the microfluidic array. Hence, in this paper, we eliminate the concept...... on the surface of the microfluidic array. We have extended the GRASP-based algorithm to consider contamination avoidance during routing-based synthesis. Several real-life examples and synthetic benchmarks are used to evaluate the proposed approaches....

  17. A facile route to synthesis of CoPt magnetic nanoparticles

    International Nuclear Information System (INIS)

    Liu, Yang; Yang, Yanting; Zhang, Yongjun; Wang, Yaxin; Zhang, Xiaolong; Jiang, Yuhong; Wei, Maobin; Liu, Yanqing; Liu, Xiaoyan; Yang, Jinghai

    2013-01-01

    Graphical abstract: CoPt NPs are successfully synthesized by sol–gel method. Different distinct particle sizes with narrow particle size distribution of CoPt nanoparticles are obtained. The maximum coercivity of 254,720.3 A/m is obtained for 800 °C heat-treated sample. Display Omitted Highlights: ► L1 0 -CoPt NPs with FCT structure are successfully synthesized by sol–gel method. ► The maximum value of 254,720.3 A/m is obtained for the samples heated at 800 °C. ► The synthetic route proposed in this study is less toxic and easy-to-handle. -- Abstract: The face-centered tetragonal (FCT) ordered L1 0 CoPt nanoparticles (NPs) are prepared by the sol–gel method. Their structure and magnetic properties are characterized by the X-ray diffraction (XRD), the transmission electron microscope (TEM) and the vibrating sample magnetometer (VSM). The results indicate that the CoPt NPs heated at 400 °C are the disordered face-centered cubic (FCC) structure, whereas the samples annealed at the temperature above 600 °C exhibit an ordered FCT structure. TEM images show the increase of the particle size as the annealing temperature increases. SAED images show the appearance of the L1 0 phase at 800 °C, and the maximum coercivity is 254,720.3 A/m.

  18. Microorganism Utilization for Synthetic Milk

    Science.gov (United States)

    Morford, Megan A.; Khodadad, Christina L.; Caro, Janicce I.; Spencer, LaShelle E.; Richards, Jeffery T.; Strayer, Richard F.; Birmele, Michele N.; Wheeler, Raymond M.

    2014-01-01

    A desired architecture for long duration spaceflight, like aboard the International Space Station or for future missions to Mars, is to provide a supply of fresh food crops for the astronauts. However, some crops can create a high proportion of inedible plant waste. The main goal of the Synthetic Biology project, Cow in a Column, was to produce the components of milk (sugar, lipid, protein) from inedible plant waste by utilizing microorganisms (fungi, yeast, bacteria). Of particular interest was utilizing the valuable polysaccharide, cellulose, found in plant waste, to naturally fuel-through microorganism cellular metabolism- the creation of sugar (glucose), lipid (milk fat), and protein (casein) in order to produce a synthetic edible food product. Environmental conditions such as pH, temperature, carbon source, aeration, and choice microorganisms were optimized in the laboratory and the desired end-products, sugars and lipids, were analyzed. Trichoderma reesei, a known cellulolytic fungus, was utilized to drive the production of glucose, with the intent that the produced glucose would serve as the carbon source for milk fat production and be a substitute for the milk sugar lactose. Lipid production would be carried out by Rhodosporidium toruloides, yeast known to accumulate those lipids that are typically found in milk fat. Results showed that glucose and total lipid content were below what was expected during this phase of experimentation. In addition, individual analysis of six fatty acids revealed that the percentage of each fatty acid was lower than naturally produced bovine milk. Overall, this research indicates that microorganisms could be utilized to breakdown inedible solid waste to produce useable products. For future work, the production of the casein protein for milk would require the development of a genetically modified organism, which was beyond the scope of the original project. Additional trials would be needed to further refine the required

  19. A general enantioselective route to the chamigrene natural product family

    KAUST Repository

    White, David E.

    2010-06-01

    Described in this report is an enantioselective route toward the chamigrene natural product family. The key disconnections in our synthetic approach include sequential enantioselective decarboxylative allylation and ring-closing olefin metathesis to form the all-carbon quaternary stereocenter and spirocyclic core present in all members of this class of compounds. The generality of this strategy is demonstrated by the first total syntheses of elatol and the proposed structure of laurencenone B, as well as the first enantioselective total syntheses of laurencenone C and α-chamigrene. A brief exploration of the substrate scope of the enantioselective decarboxylative allylation/ring-closing metathesis sequence with fully substituted vinyl chlorides is also presented.

  20. A general enantioselective route to the chamigrene natural product family

    KAUST Repository

    White, David E.; Stewart, Ian C.; Seashore-Ludlow, Brinton A.; Grubbs, Robert H.; Stoltz, Brian M.

    2010-01-01

    Described in this report is an enantioselective route toward the chamigrene natural product family. The key disconnections in our synthetic approach include sequential enantioselective decarboxylative allylation and ring-closing olefin metathesis to form the all-carbon quaternary stereocenter and spirocyclic core present in all members of this class of compounds. The generality of this strategy is demonstrated by the first total syntheses of elatol and the proposed structure of laurencenone B, as well as the first enantioselective total syntheses of laurencenone C and α-chamigrene. A brief exploration of the substrate scope of the enantioselective decarboxylative allylation/ring-closing metathesis sequence with fully substituted vinyl chlorides is also presented.

  1. Synthetic staggered architecture composites

    International Nuclear Information System (INIS)

    Dutta, Abhishek; Tekalur, Srinivasan Arjun

    2013-01-01

    Highlights: ► Composite design inspired by nature. ► Tuning microstructure via changing ceramic content and aspect ratio. ► Experimental display of structure–property correlationship in synthetic composites. - Abstract: Structural biocomposites (for example, nacre in seashells, bone, etc.) are designed according to the functional role they are delegated for. For instance, bone is primarily designed for withstanding time-dependent loading (for example, withstanding stresses while running, jumping, accidental fall) and hence the microstructure is designed primarily from enhanced toughness and moderate stiffness point of view. On the contrary, seashells (which lie in the abyss of oceans) apart from providing defense to the organism (it is hosting) against predatory attacks, are subjected to static loading (for example, enormous hydrostatic pressure). Hence, emphasis on the shell structure evolution is directed primarily towards providing enhanced stiffness. In order to conform between stiffness and toughness, nature precisely employs a staggered arrangement of inorganic bricks in a biopolymer matrix (at its most elementary level of architecture). Aspect ratio and content of ceramic bricks are meticulously used by nature to synthesize composites having varying degrees of stiffness, strength and toughness. Such an amazing capability of structure–property correlationship has rarely been demonstrated in synthetic composites. Therefore, in order to better understand the mechanical behavior of synthetic staggered composites, the problem becomes two-pronged: (a) synthesize composites with varying brick size and contents and (b) experimental investigation of the material response. In this article, an attempt has been made to synthesize and characterize staggered ceramic–polymer composites having varying aspect ratio and ceramic content using freeze-casting technique. This will in-turn help us in custom-design manufacture of hybrid bio-inspired composite materials

  2. One new route to optimize the oxidation resistance of TiC/hastelloy (Ni-based alloy) composites applied for intermediate temperature solid oxide fuel cell interconnect by increasing graphite particle size

    Science.gov (United States)

    Qi, Qian; Liu, Yan; Wang, Lujie; Zhang, Hui; Huang, Jian; Huang, Zhengren

    2017-09-01

    TiC/hastelloy composites with suitable thermal expansion and excellent electrical conductivity are promising candidates for IT-SOFC interconnect. In this paper, the TiC/hastelloy composites are fabricated by in-situ reactive infiltration, and the oxidation resistance of composites is optimized by increasing graphite particle size. Results show that the increase of graphite particles size from 1 μm to 40 μm reduces TiC particle size from 2.68 μm to 2.22 μm by affecting the formation process of TiC. Moreover, the decrease of TiC particles size accelerates the fast formation of dense and continuous TiO2/Cr2O3 oxide layer, which bring down the mass gain (800 °C/100 h) from 2.03 mg cm-2 to 1.18 mg cm-2. Meanwhile, the coefficient of thermal expansion decreases from 11.15 × 10-6 °C-1 to 10.80 × 10-6 °C-1, and electrical conductivity maintains about 5800 S cm-1 at 800 °C. Therefore, the decrease of graphite particle size is one simple and effective route to optimize the oxidation resistance of composites, and meantime keeps suitable thermal expansion and good electrical conductivity.

  3. Synthetic Aperture Ultrasound Imaging

    DEFF Research Database (Denmark)

    Jensen, Jørgen Arendt; Nikolov, Svetoslav; Gammelmark, Kim Løkke

    2006-01-01

    The paper describes the use of synthetic aperture (SA) imaging in medical ultrasound. SA imaging is a radical break with today's commercial systems, where the image is acquired sequentially one image line at a time. This puts a strict limit on the frame rate and the possibility of acquiring...... a sufficient amount of data for high precision flow estimation. These constrictions can be lifted by employing SA imaging. Here data is acquired simultaneously from all directions over a number of emissions, and the full image can be reconstructed from this data. The talk will demonstrate the many benefits...

  4. Transition in synthetic jets

    Czech Academy of Sciences Publication Activity Database

    Tesař, Václav; Kordík, Jozef

    2012-01-01

    Roč. 187, NOV 2012 (2012), s. 105-117 ISSN 0924-4247 R&D Projects: GA TA ČR(CZ) TA02020795; GA ČR(CZ) GPP101/12/P556; GA ČR(CZ) GCP101/11/J019 Institutional research plan: CEZ:AV0Z20760514 Keywords : turbulence * synthetic jet * transition * velocity spectra Subject RIV: BK - Fluid Dynamics Impact factor: 1.841, year: 2012 http://www. science direct.com/ science /article/pii/S0924424712005031

  5. Thermal and structural characterization of synthetic and natural nanocrystalline hydroxyapatite.

    Science.gov (United States)

    Sofronia, Ancuta M; Baies, Radu; Anghel, Elena M; Marinescu, Cornelia A; Tanasescu, Speranta

    2014-10-01

    The aim of this work was to study the thermal stability on heating and to obtain the processing parameters of synthetic and bone-derived hydroxyapatite over temperatures between room temperature and 1400°C by thermal analysis (thermogravimetry (TG)/differential scanning calorimetry (DSC) and thermo-mechanical analysis-TMA). Structural and surface modifications related to samples origin and calcination temperature were investigated by Fourier transformed infrared (FTIR) and Raman spectroscopy, X-ray diffraction (XRD) and BET method. FTIR spectra indicated that the organic constituents and carbonate are no longer present in the natural sample calcined at 800°C. Raman spectra highlighted the decomposition products of the hydroxyapatite. The calcination treatment modifies the processes kinetics of the synthetic samples, being able to isolate lattice water desorption processes of decarbonization and the dehydroxylation processes. Shrinkage of calcined synthetic sample increases by 10% compared to uncalcined synthetic powder. From the TMA correlated with TG analysis and heat capacity data it can be concluded that sintering temperature of the synthetic samples should be chosen in the temperature range of the onset of dehydroxylation and the temperature at which oxyapatite decomposition begins. Copyright © 2014 Elsevier B.V. All rights reserved.

  6. How to Increase the h-BN Crystallinity of Microfilms and Self-Standing Nanosheets: A Review of the Different Strategies Using the PDCs Route

    Directory of Open Access Journals (Sweden)

    Sheng Yuan

    2016-05-01

    Full Text Available Hexagonal boron nitride (h-BN is a well-known material whose use is almost restricted to lubricating applications in domains ranging from metallurgy to cosmetics. Howover, h-BN displays many other interesting properties, opening new perspectives for other engineering applications, such as as a solid lubricant in aeronautics, as the perfect substrate to graphene for electronic devices, etc. However, all these promising developments require tailored h-BN shapes displaying a high level of crystallization, ensuring its properties for the long term. Here, we developed three strategies, all associated with the Polymer Derived Ceramics (PDCs route, to prepare highly crystallized supported thick coatings and self-standing nanosheets. The first strategy concerns the innovative implementation of a Rapid Thermal Annealing to prepare micrometric h-BN coatings on thermal sensitive substrates. Compared to conventional treatment the crystallization of h-BN has successfully lowered to about 300 °C. The second strategy consists of an additivation of the used polymer precursor. Effect of lithium nitride as a crystallization promoter was investigated lowering the onset crystallization temperature from 1400 °C (traditionally to 1000 °C. This novel synthetic route allows preparing self-standing highly crystallized h-BN nanolayers. Finally, the third strategy is based on a unique combination of the PDCs route with Spark Plasma Sintering to profit of both approaches. This original method leads to large and well-crystallized flakes available for a subsequent exfoliation.

  7. Vehicle Routing With User Generated Trajectory Data

    DEFF Research Database (Denmark)

    Ceikute, Vaida; Jensen, Christian S.

    Rapidly increasing volumes of GPS data collected from vehicles provide new and increasingly comprehensive insight into the routes that drivers prefer. While routing services generally compute shortest or fastest routes, recent studies suggest that local drivers often prefer routes that are neithe...

  8. Freedom and Responsibility in Synthetic Genomics: The Synthetic Yeast Project

    OpenAIRE

    Sliva, Anna; Yang, Huanming; Boeke, Jef D.; Mathews, Debra J. H.

    2015-01-01

    First introduced in 2011, the Synthetic Yeast Genome (Sc2.0) Project is a large international synthetic genomics project that will culminate in the first eukaryotic cell (Saccharomyces cerevisiae) with a fully synthetic genome. With collaborators from across the globe and from a range of institutions spanning from do-it-yourself biology (DIYbio) to commercial enterprises, it is important that all scientists working on this project are cognizant of the ethical and policy issues associated with...

  9. Analog synthetic biology.

    Science.gov (United States)

    Sarpeshkar, R

    2014-03-28

    We analyse the pros and cons of analog versus digital computation in living cells. Our analysis is based on fundamental laws of noise in gene and protein expression, which set limits on the energy, time, space, molecular count and part-count resources needed to compute at a given level of precision. We conclude that analog computation is significantly more efficient in its use of resources than deterministic digital computation even at relatively high levels of precision in the cell. Based on this analysis, we conclude that synthetic biology must use analog, collective analog, probabilistic and hybrid analog-digital computational approaches; otherwise, even relatively simple synthetic computations in cells such as addition will exceed energy and molecular-count budgets. We present schematics for efficiently representing analog DNA-protein computation in cells. Analog electronic flow in subthreshold transistors and analog molecular flux in chemical reactions obey Boltzmann exponential laws of thermodynamics and are described by astoundingly similar logarithmic electrochemical potentials. Therefore, cytomorphic circuits can help to map circuit designs between electronic and biochemical domains. We review recent work that uses positive-feedback linearization circuits to architect wide-dynamic-range logarithmic analog computation in Escherichia coli using three transcription factors, nearly two orders of magnitude more efficient in parts than prior digital implementations.

  10. Coloring of synthetic fluorite

    International Nuclear Information System (INIS)

    Birsoy, R.

    1980-01-01

    A synthetic fluorite of the Harshaw Chemical Company is analyzed for rare earth elements, yttrium, and sodium. Samples of this fluorite are irradiated with X-rays, γ-rays, neutrons, electrons, protons, and α-particles at different energies, and their absorption spectra are analyzed. Analyzing the thermal bleaching of these radiation-coloured fluorites shows that both, impurities and radiation play a part in the coloration of synthetic fluorite. However, the main contribution comes from the radiation induced lattice defects. In the visible region spectra, the colour centre of the 5800 to 5900 A absorption band is probably mainly related with large aggregates of F-centres. The 5450 and the 5300 A absorption bands are mainly related to monovalent and divalent ion impurities and their association with lattice defects. The 3800 A absorption band seems to be related with F-centre aggregates. However, the contribution from the rare earth elements related complex color centres also plays some part for the production of this absorption band. These results indicate that the color centres of different origin can absorb light at the same wavelength. (author)

  11. Optical studies of high quality synthetic diamond

    International Nuclear Information System (INIS)

    Sharp, S.J.

    1999-01-01

    This thesis is concerned with the study of fundamental and defect induced optical properties of synthetic diamond grown using high pressure, high temperature (HPHT) synthesis or chemical vapour deposition (CVD). The primary technique used for investigation is cathodoluminescence (including imaging and decay-time measurements) in addition to other forms of optical spectroscopy. This thesis is timely in that the crystallinity and purity of synthetic diamond has increased ten fold over the last few years. The diamond exciton emission, which is easily quenched by the presence of defects, is studied in high quality samples in detail. In addition the ability now exists to engineer the isotopic content of synthetic diamond to a high degree of accuracy. The experimental chapters are divided as follows: Chapter 2: High resolution, low temperature spectra reveal a splitting of the free-exciton phonon recombination emission peaks and the bound-exciton zero phonon line. Included are measurements of the variation in intensity and decay-time as a function of temperature. Chapter 3: The shift in energy of the phonon-assisted free-exciton phonon replicas with isotopic content has been measured. The shift is in agreement with the results of interatomic force model for phonon scattering due to isotope disorder. Chapter 4: A study of the shift in energy with isotopic content of the diamond of the GR1 band due to the neutral vacancy has allowed a verification of the theoretical predictions due to the Jahn Teller effect. Chapter 5: The spatial distribution of the free-exciton luminescence is studied in HPHT synthetic and CVD diamond. A variation in intensity with distance from the surface is interpreted as a significant non-radiative loss of excitons to the surface. Chapter 6: The decay-times of all known self-interstitial related centres have been measured in order to calculate the concentration of these centres present in electron irradiated diamond. (author)

  12. Route Flap Damping Made Usable

    Science.gov (United States)

    Pelsser, Cristel; Maennel, Olaf; Mohapatra, Pradosh; Bush, Randy; Patel, Keyur

    The Border Gateway Protocol (BGP), the de facto inter-domain routing protocol of the Internet, is known to be noisy. The protocol has two main mechanisms to ameliorate this, MinRouteAdvertisementInterval (MRAI), and Route Flap Damping (RFD). MRAI deals with very short bursts on the order of a few to 30 seconds. RFD deals with longer bursts, minutes to hours. Unfortunately, RFD was found to severely penalize sites for being well-connected because topological richness amplifies the number of update messages exchanged. So most operators have disabled it. Through measurement, this paper explores the avenue of absolutely minimal change to code, and shows that a few RFD algorithmic constants and limits can be trivially modified, with the result being damping a non-trivial amount of long term churn without penalizing well-behaved prefixes' normal convergence process.

  13. Hydrothermal Gasification Of Synthetic Liquefied Wood To Methane

    Energy Technology Data Exchange (ETDEWEB)

    Waldner, M.H.; De Boni, E.; Vogel, F.

    2005-03-01

    Biomass can be effectively converted to synthetic natural gas (SNG) in a hydrothermal environment. Lower temperatures favor the production of methane rather than hydrogen. At around 420 C, catalysts are needed to ensure reasonable rates of reaction. They are tested in a new rig in terms of activity, selectivity and stability. Gold-plated surfaces ensure no interference from the stainless steel. Experiments were carried out using different feeds, such as ethanol and synthetic liquefied wood. (author)

  14. Space Synthetic Biology Project

    Science.gov (United States)

    Howard, David; Roman, Monsi; Mansell, James (Matt)

    2015-01-01

    Synthetic biology is an effort to make genetic engineering more useful by standardizing sections of genetic code. By standardizing genetic components, biological engineering will become much more similar to traditional fields of engineering, in which well-defined components and subsystems are readily available in markets. Specifications of the behavior of those components and subsystems can be used to model a system which incorporates them. Then, the behavior of the novel system can be simulated and optimized. Finally, the components and subsystems can be purchased and assembled to create the optimized system, which most often will exhibit behavior similar to that indicated by the model. The Space Synthetic Biology project began in 2012 as a multi-Center effort. The purpose of this project was to harness Synthetic Biology principals to enable NASA's missions. A central target for application was to Environmental Control & Life Support (ECLS). Engineers from NASA Marshall Space Flight Center's (MSFC's) ECLS Systems Development Branch (ES62) were brought into the project to contribute expertise in operational ECLS systems. Project lead scientists chose to pursue the development of bioelectrochemical technologies to spacecraft life support. Therefore, the ECLS element of the project became essentially an effort to develop a bioelectrochemical ECLS subsystem. Bioelectrochemical systems exploit the ability of many microorganisms to drive their metabolisms by direct or indirect utilization of electrical potential gradients. Whereas many microorganisms are capable of deriving the energy required for the processes of interest (such as carbon dioxide (CO2) fixation) from sunlight, it is believed that subsystems utilizing electrotrophs will exhibit smaller mass, volume, and power requirements than those that derive their energy from sunlight. In the first 2 years of the project, MSFC personnel conducted modeling, simulation, and conceptual design efforts to assist the

  15. Current status of synthetic epikeratoplasty.

    Science.gov (United States)

    Thompson, K P; Hanna, K; Waring, G O; Gipson, I; Liu, Y; Gailitis, R P; Johnson-Wint, B; Green, K

    1991-01-01

    Many of the deficiencies with human tissue epikeratoplasty might be improved by the use of a suitable synthetic lenticule. Potential biomaterials for epikeratoplasty include collagen (types I, III, or IV), collagen-hydrogel copolymers, bioactive synthetics, and coated hydrogels. The biomaterial must be engineered to achieve strict specifications of optical clarity, support of epithelial migration and adhesion, permeability to solutes, and stability to corneal proteases. Attaching synthetic lenticules to the cornea without cutting Bowman's layer by adhesives, laser welding, or direct adhesion may also improve the efficacy of synthetic epikeratoplasty.

  16. Synthetic biology and occupational risk.

    Science.gov (United States)

    Howard, John; Murashov, Vladimir; Schulte, Paul

    2017-03-01

    Synthetic biology is an emerging interdisciplinary field of biotechnology that involves applying the principles of engineering and chemical design to biological systems. Biosafety professionals have done an excellent job in addressing research laboratory safety as synthetic biology and gene editing have emerged from the larger field of biotechnology. Despite these efforts, risks posed by synthetic biology are of increasing concern as research procedures scale up to industrial processes in the larger bioeconomy. A greater number and variety of workers will be exposed to commercial synthetic biology risks in the future, including risks to a variety of workers from the use of lentiviral vectors as gene transfer devices. There is a need to review and enhance current protection measures in the field of synthetic biology, whether in experimental laboratories where new advances are being researched, in health care settings where treatments using viral vectors as gene delivery systems are increasingly being used, or in the industrial bioeconomy. Enhanced worker protection measures should include increased injury and illness surveillance of the synthetic biology workforce; proactive risk assessment and management of synthetic biology products; research on the relative effectiveness of extrinsic and intrinsic biocontainment methods; specific safety guidance for synthetic biology industrial processes; determination of appropriate medical mitigation measures for lentiviral vector exposure incidents; and greater awareness and involvement in synthetic biology safety by the general occupational safety and health community as well as by government occupational safety and health research and regulatory agencies.

  17. Finding Hope in Synthetic Biology.

    Science.gov (United States)

    Takala, Tuija

    2017-04-01

    For some, synthetic biology represents great hope in offering possible solutions to many of the world's biggest problems, from hunger to sustainable development. Others remain fearful of the harmful uses, such as bioweapons, that synthetic biology can lend itself to, and most hold that issues of biosafety are of utmost importance. In this article, I will evaluate these points of view and conclude that although the biggest promises of synthetic biology are unlikely to become reality, and the probability of accidents is fairly substantial, synthetic biology could still be seen to benefit humanity by enhancing our ethical understanding and by offering a boost to world economy.

  18. Tissue Harmonic Synthetic Aperture Imaging

    DEFF Research Database (Denmark)

    Rasmussen, Joachim

    The main purpose of this PhD project is to develop an ultrasonic method for tissue harmonic synthetic aperture imaging. The motivation is to advance the field of synthetic aperture imaging in ultrasound, which has shown great potentials in the clinic. Suggestions for synthetic aperture tissue...... system complexity compared to conventional synthetic aperture techniques. In this project, SASB is sought combined with a pulse inversion technique for 2nd harmonic tissue harmonic imaging. The advantages in tissue harmonic imaging (THI) are expected to further improve the image quality of SASB...

  19. Life after the synthetic cell

    DEFF Research Database (Denmark)

    Rasmussen, Steen

    2010-01-01

    Nature asked eight synthetic-biology experts about the implications for science and society of the “synthetic cell” made by the J. Craig Venter Institute (JCVI). The institute's team assembled, modified and implanted a synthesized genome into a DNA-free bacterial shell to make a self-replicating ......Nature asked eight synthetic-biology experts about the implications for science and society of the “synthetic cell” made by the J. Craig Venter Institute (JCVI). The institute's team assembled, modified and implanted a synthesized genome into a DNA-free bacterial shell to make a self...

  20. Computational synthetic geometry

    CERN Document Server

    Bokowski, Jürgen

    1989-01-01

    Computational synthetic geometry deals with methods for realizing abstract geometric objects in concrete vector spaces. This research monograph considers a large class of problems from convexity and discrete geometry including constructing convex polytopes from simplicial complexes, vector geometries from incidence structures and hyperplane arrangements from oriented matroids. It turns out that algorithms for these constructions exist if and only if arbitrary polynomial equations are decidable with respect to the underlying field. Besides such complexity theorems a variety of symbolic algorithms are discussed, and the methods are applied to obtain new mathematical results on convex polytopes, projective configurations and the combinatorics of Grassmann varieties. Finally algebraic varieties characterizing matroids and oriented matroids are introduced providing a new basis for applying computer algebra methods in this field. The necessary background knowledge is reviewed briefly. The text is accessible to stud...

  1. Synthetic Aperture Compound Imaging

    DEFF Research Database (Denmark)

    Hansen, Jens Munk

    and the limiting factor is the amount of memory IO resources available. An equally high demand for memory throughput is found in the computer gaming industry, where a large part of the processing takes place on the graphics processing unit (GPU). Using the GPU, a framework for synthetic aperture imaging......Medical ultrasound imaging is used for many purposes, e.g. for localizing and classifying cysts, lesions, and other processes. Almost any mass is first observed using B-mode imaging and later classified using e.g. color flow, strain, or attenuation imaging. It is therefore important that the B......-mode images have high contrast. Like all imaging modalities, ultrasound is subject to a number of inherent artifacts that compromise image quality. The most prominent artifact is the degradation by coherent wave interference, known as “speckle”, which gives a granular appearance to an otherwise homogeneous...

  2. Transionospheric synthetic aperture imaging

    CERN Document Server

    Gilman, Mikhail; Tsynkov, Semyon

    2017-01-01

    This landmark monograph presents the most recent mathematical developments in the analysis of ionospheric distortions of SAR images and offers innovative new strategies for their mitigation. As a prerequisite to addressing these topics, the book also discusses the radar ambiguity theory as it applies to synthetic aperture imaging and the propagation of radio waves through the ionospheric plasma, including the anisotropic and turbulent cases. In addition, it covers a host of related subjects, such as the mathematical modeling of extended radar targets (as opposed to point-wise targets) and the scattering of radio waves off those targets, as well as the theoretical analysis of the start-stop approximation, which is used routinely in SAR signal processing but often without proper justification. The mathematics in this volume is clean and rigorous – no assumptions are hidden or ambiguously stated. The resulting work is truly interdisciplinary, providing both a comprehensive and thorough exposition of the field,...

  3. Radioimmunoassay of synthetic steroids

    Energy Technology Data Exchange (ETDEWEB)

    Raynaud, J -P; Bucourt, R; Salmon, J

    1975-12-01

    The sensitivity of a radioimmunoassay depends on the intrinsic association constant of the interaction between ligand and antibody. Its specificity depends on the position of the chain which forms the link with the antigen. Thus, an antibody specific of estradiol has been obtained by coupling estradiol to albumin via a chain at position 7. For synthetic steroids the structure of which is sufficiency different from that of natural hormones, the requirements for a sensitive assay method not involving chromatography are simply maximum affinity and positioning of the couple at a site which does not undergo metabolic attack. These criteria were used to develop assays for R 2858 and R 2453 which obviate the need to administer radioactive product in clinical pharmacology. Cross-reaction with structural analogs may be used to assay competitors. Thus, R 2323 antibody, highly specific for endogenous steroids, may be used to assay other trienes such as R 1697 (trenbolone) and R 2010 (norgestrienone).

  4. Effect of annealing temperature on optical properties of binary zinc tin oxide nano-composite prepared by sol-gel route using simple precursors: structural and optical studies by DRS, FT-IR, XRD, FESEM investigations.

    Science.gov (United States)

    Habibi, Mohammad Hossein; Mardani, Maryam

    2015-02-25

    Binary zinc tin oxide nano-composite was synthesized by a facile sol-gel method using simple precursors from the solutions consisting of zinc acetate, tin(IV) chloride and ethanol. Effect of annealing temperature on optical and structural properties was investigated using X-ray diffraction (XRD), diffuse reflectance spectra (DRS), field emission scanning electron microscopy (FESEM) and Fourier transform infrared spectroscopy (FTIR). XRD results revealed the existence of the ZnO and SnO2 phases. FESEM results showed that binary zinc tin oxide nano-composites ranges from 56 to 60 nm in diameter at 400°C and 500°C annealing temperatures respectively. The optical band gap was increased from 2.72 eV to 3.11 eV with the increasing of the annealing temperature. FTIR results confirmed the presence of zinc oxide and tin oxide and the broad absorption peaks at 3426 and 1602 cm(-1) can be ascribed to the vibration of absorptive water, and the absorption peaks at 546, 1038 and 1410 cm(-1) are due to the vibration of Zn-O or Sn-O groups in binary zinc tin oxide. Copyright © 2014 Elsevier B.V. All rights reserved.

  5. Natural and Synthetic Barriers to Immobilize Radionuclides

    International Nuclear Information System (INIS)

    Um, W.

    2011-01-01

    The experiments of weathering of glass waste form and the reacted sediments with simulated glass leachates show that radionuclide sequestration can be significantly enhanced by promoting the formation of secondary precipitates. In addition, synthetic phosphate-bearing nanoporous material exhibits high stability at temperature and has a very high K d value for U(VI) removal. Both natural and synthetic barrier materials can be used as additional efficient adsorbents for retarding transport of radionuclides for various contaminated waste streams and waste forms present at U. S. Department of Energy clean-up sites and the proposed geologic radioactive waste disposal facility. In the radioactive waste repository facility, natural or synthetic materials are planned to be used as a barrier material to immobilize and retard radionuclide release. The getter material can be used to selectively scavenge the radionuclide of interest from a liquid waste stream and subsequently incorporate the loaded getters in a cementitious or various monolithic waste forms. Also, the getter material is to reduce the release of radionuclides from monolithic waste forms. Also, the getter material is to reduce the release of radionuclides from monolithic waste forms. Also, the getter material is to reduce the release of radionuclides form monolithic waste forms by being emplaced as a backfill barrier material around the wastes or waste form to minimize the potential around the wastes or waste form to minimize the potential hazard of leached radioactive wastes. The barrier material should be highly efficient to sequester radionuclides and possess physical and chemical stability for long-term exposure to severe weathering conditions. Because potential leaching of radionuclides depends on various environmental and weathering conditions of the near-field repository, the barrier materials must be durable and not disintegrate under a range of moisture, temperature, pressure, radiation, Eh, ph. and

  6. Experience with synthetic fluorinated fluid lubricants

    Science.gov (United States)

    Conley, Peter L.; Bohner, John J.

    1990-01-01

    Since the late 1970's, the wet lubricant of choice for space mechanisms has been one of the family of synthetic perfluoro polyalkylether (PFPE) compounds, namely Fomblin Z-25 (Bray-815Z) or DuPont's Krytox 143xx series. While offering the advantages of extremely low vapor pressures and wide temperature ranges, these oils and derived greases have a complex chemistry compared to the more familiar natural and synthetic hydrocarbons. Many aerospace companies have conducted test programs to characterize the behavior of these compounds in a space environment, resulting in a large body of hard knowledge as well as considerable space lore concerning the suitability of the lubricants for particular applications and techniques for successful application. The facts are summarized and a few myths about the compounds are dispelled, and some performance guidelines for the mechanism design engineer are provided.

  7. Dynamic Routing during Disaster Events

    NARCIS (Netherlands)

    Fitrianie, S.; Rothkrantz, L.J.M.

    2015-01-01

    Innovations in mobile technology allow people to request route information on their smartphone to reach safe areas during emergency and disaster evacuations. In return, the affected people in the field can send their observation reports, e.g. using a dedicated icon-based disaster language. However,

  8. Overview: Routes to Open Access

    OpenAIRE

    Tullney, Marco; van Wezenbeek, Wilma

    2017-01-01

    Slides of an overview presentation given at a CESAER workshop on Open Access, February 2nd, 2017, in Brussels Cover major routes to more open access as discussed in the Task Force Open Science of CESAER: (national) open access strategies open access mandates open access incentives open access awareness open access publishing open access infrastructure

  9. Dynamic Weather Routes Architecture Overview

    Science.gov (United States)

    Eslami, Hassan; Eshow, Michelle

    2014-01-01

    Dynamic Weather Routes Architecture Overview, presents the high level software architecture of DWR, based on the CTAS software framework and the Direct-To automation tool. The document also covers external and internal data flows, required dataset, changes to the Direct-To software for DWR, collection of software statistics, and the code structure.

  10. Emissions allocation in transportation routes

    NARCIS (Netherlands)

    Leenders, B.P.J.; Velázquez Martínez, J.; Fransoo, J.C.

    2017-01-01

    This article studies the allocation of CO2 emissions to a specific shipment in routing transportation. The authors show that this problem differs from a cost allocation problem specifically because the concavity condition does not hold necessarily in the CO2 allocation problem. This implies that a

  11. Roots/Routes: Part I

    Science.gov (United States)

    Swanson, Dalene M.

    2009-01-01

    This narrative and poetic rendering acts as an articulation of a journey of many routes. It is a storying of critical research issues and events as performances of lived experience. It is a metissage of hybrid, but interrelated, themes that find cohesion through fragmentation and coalescence, severance, and regrowth. These themes are invoked by…

  12. Roots/Routes: Part II

    Science.gov (United States)

    Swanson, Dalene M.

    2009-01-01

    This narrative acts as an articulation of a journey of many routes. Following Part I of the same research journey of rootedness/routedness, it debates the nature of transformation and transcendence beyond personal and political paradoxes informed by neoliberalism and related repressive globalizing discourses. Through a more personal, descriptive,…

  13. 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.

  14. Thermal and structural characterization of synthetic and natural nanocrystalline hydroxyapatite

    International Nuclear Information System (INIS)

    Sofronia, Ancuta M.; Baies, Radu; Anghel, Elena M.; Marinescu, Cornelia A.; Tanasescu, Speranta

    2014-01-01

    The aim of this work was to study the thermal stability on heating and to obtain the processing parameters of synthetic and bone-derived hydroxyapatite over temperatures between room temperature and 1400 °C by thermal analysis (thermogravimetry (TG)/differential scanning calorimetry (DSC) and thermo-mechanical analysis—TMA). Structural and surface modifications related to samples origin and calcination temperature were investigated by Fourier transformed infrared (FTIR) and Raman spectroscopy, X-ray diffraction (XRD) and BET method. FTIR spectra indicated that the organic constituents and carbonate are no longer present in the natural sample calcined at 800 °C. Raman spectra highlighted the decomposition products of the hydroxyapatite. The calcination treatment modifies the processes kinetics of the synthetic samples, being able to isolate lattice water desorption processes of decarbonization and the dehydroxylation processes. Shrinkage of calcined synthetic sample increases by 10% compared to uncalcined synthetic powder. From the TMA correlated with TG analysis and heat capacity data it can be concluded that sintering temperature of the synthetic samples should be chosen in the temperature range of the onset of dehydroxylation and the temperature at which oxyapatite decomposition begins. - Highlights: • Specific surface area of HA powder was reduced from 19.2 to 9.5 m 2 /g by calcination. • Raman spectra indicate the presence of B-type CO 3 group in HA synthetic samples. • The onset temperature of HA densification and dehydroxylation processes correspond. • Calcination of HA influences reactions kinetics with consequences on densification. • Shrinkage of calcined HA sample increases by 10% with respect to uncalcined sample

  15. Thermal and structural characterization of synthetic and natural nanocrystalline hydroxyapatite

    Energy Technology Data Exchange (ETDEWEB)

    Sofronia, Ancuta M. [Ilie Murgulescu Institute of Physical Chemistry of the Romanian Academy, 060021 Bucharest (Romania); Baies, Radu [National Research Institute for Electrochemistry and Condensed Matter, 300224 Timisoara (Romania); Anghel, Elena M. [Ilie Murgulescu Institute of Physical Chemistry of the Romanian Academy, 060021 Bucharest (Romania); Marinescu, Cornelia A., E-mail: alcorina@chimfiz.icf.ro [Ilie Murgulescu Institute of Physical Chemistry of the Romanian Academy, 060021 Bucharest (Romania); Tanasescu, Speranta [Ilie Murgulescu Institute of Physical Chemistry of the Romanian Academy, 060021 Bucharest (Romania)

    2014-10-01

    The aim of this work was to study the thermal stability on heating and to obtain the processing parameters of synthetic and bone-derived hydroxyapatite over temperatures between room temperature and 1400 °C by thermal analysis (thermogravimetry (TG)/differential scanning calorimetry (DSC) and thermo-mechanical analysis—TMA). Structural and surface modifications related to samples origin and calcination temperature were investigated by Fourier transformed infrared (FTIR) and Raman spectroscopy, X-ray diffraction (XRD) and BET method. FTIR spectra indicated that the organic constituents and carbonate are no longer present in the natural sample calcined at 800 °C. Raman spectra highlighted the decomposition products of the hydroxyapatite. The calcination treatment modifies the processes kinetics of the synthetic samples, being able to isolate lattice water desorption processes of decarbonization and the dehydroxylation processes. Shrinkage of calcined synthetic sample increases by 10% compared to uncalcined synthetic powder. From the TMA correlated with TG analysis and heat capacity data it can be concluded that sintering temperature of the synthetic samples should be chosen in the temperature range of the onset of dehydroxylation and the temperature at which oxyapatite decomposition begins. - Highlights: • Specific surface area of HA powder was reduced from 19.2 to 9.5 m{sup 2}/g by calcination. • Raman spectra indicate the presence of B-type CO{sub 3} group in HA synthetic samples. • The onset temperature of HA densification and dehydroxylation processes correspond. • Calcination of HA influences reactions kinetics with consequences on densification. • Shrinkage of calcined HA sample increases by 10% with respect to uncalcined sample.

  16. Intracellular Route of Canine Parvovirus Entry

    Science.gov (United States)

    Vihinen-Ranta, Maija; Kalela, Anne; Mäkinen, Päivi; Kakkola, Laura; Marjomäki, Varpu; Vuento, Matti

    1998-01-01

    The present study was designed to investigate the endocytic pathway involved in canine parvovirus (CPV) infection. Reduced temperature (18°C) or the microtubule-depolymerizing drug nocodazole was found to inhibit productive infection of canine A72 cells by CPV and caused CPV to be retained in cytoplasmic vesicles as indicated by immunofluorescence microscopy. Consistent with previously published results, these data indicate that CPV enters a host cell via an endocytic route and further suggest that microtubule-dependent delivery of CPV to late endosomes is required for productive infection. Cytoplasmic microinjection of CPV particles was used to circumvent the endocytosis and membrane fusion steps in the entry process. Microinjection experiments showed that CPV particles which were injected directly into the cytoplasm, thus avoiding the endocytic pathway, were unable to initiate progeny virus production. CPV treated at pH 5.0 prior to microinjection was unable to initiate virus production, showing that factors of the endocytic route other than low pH are necessary for the initiation of infection by CPV. PMID:9420290

  17. Imaging with Synthetic Aperture Radar

    CERN Document Server

    Massonnet, Didier

    2008-01-01

    Describing a field that has been transformed by the recent availability of data from a new generation of space and airborne systems, the authors offer a synthetic geometrical approach to the description of synthetic aperture radar, one that addresses physicists, radar specialists, as well as experts in image processing.  

  18. Synthetic peptides for antibody production

    NARCIS (Netherlands)

    Zegers, N.D.

    1995-01-01

    Synthetic peptides are useful tools for the generation of antibodies. The use of antibodies as specific reagents in inununochemical assays is widely applied. In this chapter, the application of synthetic peptides for the generation of antibodies is described. The different steps that lead to the

  19. Synthetic peptides for antibody production

    NARCIS (Netherlands)

    N.D. Zegers (Netty)

    1995-01-01

    textabstractSynthetic peptides are useful tools for the generation of antibodies. The use of antibodies as specific reagents in inununochemical assays is widely applied. In this chapter, the application of synthetic peptides for the generation of antibodies is described. The different steps

  20. The Ethics of Synthetic Biology

    DEFF Research Database (Denmark)

    Christiansen, Andreas

    The dissertation analyses and discusses a number of ethical issues that have been raised in connection with the development of synthetic biology. Synthetic biology is a set of new techniques for DNA-level design and construction of living beings with useful properties. The dissertation especially...

  1. Synthetic biology of polyketide synthases

    DEFF Research Database (Denmark)

    Yuzawa, Satoshi; Backman, Tyler W.H.; Keasling, Jay D.

    2018-01-01

    ). The modules are composed of enzymatic domains that share sequence and functional similarity across all known PKSs. We have used the nomenclature of synthetic biology to classify the enzymatic domains and modules as parts and devices, respectively, and have generated detailed lists of both. In addition, we...... realize the potential that synthetic biology approaches bring to this class of molecules....

  2. The Time Window Vehicle Routing Problem Considering Closed Route

    Science.gov (United States)

    Irsa Syahputri, Nenna; Mawengkang, Herman

    2017-12-01

    The Vehicle Routing Problem (VRP) determines the optimal set of routes used by a fleet of vehicles to serve a given set of customers on a predefined graph; the objective is to minimize the total travel cost (related to the travel times or distances) and operational cost (related to the number of vehicles used). In this paper we study a variant of the predefined graph: given a weighted graph G and vertices a and b, and given a set X of closed paths in G, find the minimum total travel cost of a-b path P such that no path in X is a subpath of P. Path P is allowed to repeat vertices and edges. We use integer programming model to describe the problem. A feasible neighbourhood approach is proposed to solve the model

  3. Characterization of high speed synthetic jet actuators

    Science.gov (United States)

    Pikcilingis, Lucia

    Over the last 20 years, synthetic jets have been studied as a means for aerodynamic active flow control. Specifically, synthetic jets provide momentum transfer with zero-net mass flux, which has been proven to be effective for controlling flow fields. A synthetic jet is created by the periodic formation of vortex rings at its orifice due to the periodic motion of a piezoelectric disk(s). The present study seeks to optimize the performance of a synthetic jet actuator by utilizing different geometrical parameters such as disk thickness, orifice width and length, cavity height and cavity diameter, and different input parameters such as driving voltage and frequency. Two apparatuses were used with a cavity diameter of either 80 mm or 160 mm. Piezoelectric-based disks were provided by the Mide Corporation. Experiments were conducted using several synthetic jet apparatuses designed for various geometrical parameters utilizing a dual disk configuration. Velocity and temperature measurements were acquired at the center of the synthetic jet orifice using a temperature compensated hotwire and thermocouple probe. The disk(s) displacement was measured at the center of the disk with a laser displacement sensor. It was shown that the synthetic jets, having the 80 mm cavity diameter, are capable of exceeding peak velocities of 200 m/s with a relatively large orifice of dimensions AR = 12, hc* = 3, and hn* = 4. In addition, the conditions at which the disks were manufactured had minimal effect on the performance of the jet, except for the pair with overnight resting time as opposed to less than an hour resting time for the control units. Altering the tab style of the disks, where the tab allows the electrical circuit to be exposed for external power connection, showed that a thin fragile tab versus a tab of the same thickness as the disk has minimal effect on the performance but affects the durability of the disk due to the fragility or robustness of the tab. The synthetic jets

  4. Technical Report: Sleep-Route - Routing through Sleeping Sensors

    OpenAIRE

    Sarkar, Chayan; Rao, Vijay S.; Prasad, R. Venkatesha

    2014-01-01

    In this article, we propose an energy-efficient data gathering scheme for wireless sensor network called Sleep-Route, which splits the sensor nodes into two sets - active and dormant (low-power sleep). Only the active set of sensor nodes participate in data collection. The sensing values of the dormant sensor nodes are predicted with the help of an active sensor node. Virtual Sensing Framework (VSF) provides the mechanism to predict the sensing values by exploiting the data correlation among ...

  5. Fast-grown CdS quantum dots: Single-source precursor approach vs microwave route

    Energy Technology Data Exchange (ETDEWEB)

    Fregnaux, Mathieu [Laboratoire de Chimie et Physique: Approche Multi-échelles des Milieux Complexes, Institut Jean Barriol, Université de Lorraine, 1 Boulevard Arago, 57070 Metz (France); Dalmasso, Stéphane, E-mail: stephane.dalmasso@univ-lorraine.fr [Laboratoire de Chimie et Physique: Approche Multi-échelles des Milieux Complexes, Institut Jean Barriol, Université de Lorraine, 1 Boulevard Arago, 57070 Metz (France); Durand, Pierrick [Laboratoire de Cristallographie, Résonance Magnétique et Modélisations, Institut Jean Barriol, Université de Lorraine, UMR CNRS 7036, Faculté des Sciences, BP 70239, 54506 Vandoeuvre lès Nancy (France); Zhang, Yudong [Laboratoire d' Etude des Microstructures et de Mécanique des Matériaux, Université de Lorraine, UMR CNRS 7239, Ile du Saulcy, 57045 Metz cedex 01 (France); Gaumet, Jean-Jacques; Laurenti, Jean-Pierre [Laboratoire de Chimie et Physique: Approche Multi-échelles des Milieux Complexes, Institut Jean Barriol, Université de Lorraine, 1 Boulevard Arago, 57070 Metz (France)

    2013-10-01

    A cross-disciplinary protocol of characterization by joint techniques enables one to closely compare chemical and physical properties of CdS quantum dots (QDs) grown by single source precursor methodology (SSPM) or by microwave synthetic route (MWSR). The results are discussed in relation with the synthesis protocols. The QD average sizes, reproducible as a function of the temperatures involved in the growth processes, range complementarily in 2.8–4.5 nm and 4.5–5.2 nm for SSPM and MWSR, respectively. Hexagonal and cubic structures after X-ray diffraction on SSPM and MWSR grown CdS QDs, respectively, are tentatively correlated to a better crystalline quality of the latter with respect to the further ones, suggested by (i) a remarkable stability of the MWSR grown QDs after exposure to air during several days and (ii) no evidence of their fragmentation during mass spectrometry (MS) analyses, after a fair agreement between size dispersities obtained by transmission electron microscopy (TEM) and MS, in contrast with the discrepancy found for the SSPM grown QDs. Correlatively, a better optical quality is suggested for the MWSR grown QDs by the resolution of n > 1 excitonic transitions in their absorption spectra. The QD average sizes obtained by TEM and deduced from MS are in overall agreement. This agreement is improved for the MWSR grown QDs, taking into account a prolate shape of the QDs also observed in the TEM images. For both series of samples, the excitonic responses vs the average sizes are consistent with the commonly admitted empirical energy-size correspondence. A low energy PL band is observed in the case of the SSPM grown QDs. Its decrease in intensity with QD size increase suggests a surface origin tentatively attributed to S vacancies. In the case of the MWSR grown QDs, the absence of this PL is tentatively correlated to an absence of S vacancies and therefore to the stable behavior observed when the QDs are exposed to air. - Highlights: • Single

  6. Route Scherrer and Route Einstein closed for construction work

    CERN Multimedia

    2015-01-01

    Please note that Route Scherrer will be inaccessible for two and a half months from the beginning of March and that part of Route Einstein will be closed for two weeks from the end of February.   Figure 1. The part of Route Scherrer between Building 510 and Building 53 (see Figure 1) will be closed from the beginning of March until mid-May for civil engineering works.   The superheated water pipes supplying the buildings in this area date back to 1959 and therefore present a significant risk of leakage. In order to ensure the reliable supply of superheated water, and, by extension, heating, to all premises near the Main Building (i.e. Buildings 500, 501, 503, 60, 62, 63 and 64), a new buried service duct will be installed between the basements of Buildings 53 and 61 to house a new superheated water pipe. Figure 2. The following car parks will, however, remain accessible for the duration of the works: the Cèdres car park, the car park for Buildings 4 and 5, and the ca...

  7. Highway route controlled quantity shipment routing reports - An overview

    International Nuclear Information System (INIS)

    Cashwell, J.W.; Welles, B.W.; Welch, M.J.

    1989-01-01

    US Department of Transportation (DOT) regulations require a postnotification report from the shipper for all shipments of radioactive materials categorized as a Highway Route Controlled Quantity. These postnotification reports, filed in compliance with 49 CFR 172.203(d), have been compiled by the DOT in a database known as the Radioactive Materials Routing Report (RAMRT) since 1982. The data were sorted by each of its elements to establish historical records and trends of Highway Route Controlled Quantity shipments from 1982 through 1987. Approximately 1520 records in the RAMRT database were compiled for this analysis. Approximately half of the shipments reported for the study period were from the US Department of Energy (DOE) and its contractors, with the others being commercial movements. Two DOE installations, EG and G Idaho and Oak Ridge, accounted for nearly half of the DOE activities. Similarly, almost half of the commercial movements were reported by two vendors, Nuclear Assurance Corporation and Transnuclear, Incorporated. Spent fuel from power and research reactors accounted for approximately half of all shipments

  8. A facile room temperature route to ternary Cu{sub 7.2}S{sub 2}Se{sub 2} compounds and their photovoltaic properties based on elemental copper

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, Jiamei [Department of Chemistry, Zhengzhou University, Henan 450001 (China); Key Laboratory of Micro-Nano Materials for Energy Storage and Conversion of Henan Province, Institute of Surface Micro and Nano Materials, Xuchang University, Henan 461000 (China); Jia, Huimin, E-mail: zhengzhi99999@gmail.com [Key Laboratory of Micro-Nano Materials for Energy Storage and Conversion of Henan Province, Institute of Surface Micro and Nano Materials, Xuchang University, Henan 461000 (China); Lei, Yan [Key Laboratory of Micro-Nano Materials for Energy Storage and Conversion of Henan Province, Institute of Surface Micro and Nano Materials, Xuchang University, Henan 461000 (China); Liu, Songzi [Department of Chemistry, Zhengzhou University, Henan 450001 (China); Key Laboratory of Micro-Nano Materials for Energy Storage and Conversion of Henan Province, Institute of Surface Micro and Nano Materials, Xuchang University, Henan 461000 (China); Gao, Yuanhao [Key Laboratory of Micro-Nano Materials for Energy Storage and Conversion of Henan Province, Institute of Surface Micro and Nano Materials, Xuchang University, Henan 461000 (China); Hou, Hongwei [Department of Chemistry, Zhengzhou University, Henan 450001 (China); Zheng, Zhi, E-mail: zzheng@xcu.edu.cn [Key Laboratory of Micro-Nano Materials for Energy Storage and Conversion of Henan Province, Institute of Surface Micro and Nano Materials, Xuchang University, Henan 461000 (China)

    2017-06-01

    A one-pot synthesis of novel hierarchical flower-like Cu{sub 7.2}S{sub 2}Se{sub 2} nanocrystals was developed based on the direct metal surface elemental reaction (DMSER) method. This new room temperature synthesis is an economic and environmentally friendly soft chemical approach. The prepared Cu{sub 7.2}S{sub 2}Se{sub 2} nanocrystals uniformly cover the surface of the Cu substrates. The mechanism of formation was investigated by observing the materials produced from changing the reaction time, the molar ratio of Na{sub 2}S to elemental selenium, and the volume of solvent. The crystal structure, surface morphologies and light absorption properties were collected by X-ray diffraction (XRD), field emission scanning electron microscopy (SEM), transmission electron microscopy (TEM), and UV–visible spectroscopy. The results show that the as-prepared ternary nanocrystals are face-centered cubic and have an optical bandgap of 1.58 eV, which is ideal for potential solar cell applications. Transient photovoltage spectroscopy (TPV) was used to evaluate the photovoltaic performance of pure Cu{sub 7.2}S{sub 2}Se{sub 2} nanocrystalline powder as well as in-situ generated Cu{sub 7.2}S{sub 2}Se{sub 2}/ZnO heterojunctions. The current work offers a novel and simple approach for preparing ternary chalcogenide semiconductors for photoelectric and photocatalytic applications. - Highlights: • A one-pot synthesis of novel hierarchical flower-like Cu{sub 7.2}S{sub 2}Se{sub 2} was developed. • This work offers a facile way for prepare ternary chalcogenide at room temperature. • TPV was firstly used to evaluate the photovoltaic performance of Cu{sub 7.2}S{sub 2}Se{sub 2}.

  9. Computing with synthetic protocells.

    Science.gov (United States)

    Courbet, Alexis; Molina, Franck; Amar, Patrick

    2015-09-01

    In this article we present a new kind of computing device that uses biochemical reactions networks as building blocks to implement logic gates. The architecture of a computing machine relies on these generic and composable building blocks, computation units, that can be used in multiple instances to perform complex boolean functions. Standard logical operations are implemented by biochemical networks, encapsulated and insulated within synthetic vesicles called protocells. These protocells are capable of exchanging energy and information with each other through transmembrane electron transfer. In the paradigm of computation we propose, protoputing, a machine can solve only one problem and therefore has to be built specifically. Thus, the programming phase in the standard computing paradigm is represented in our approach by the set of assembly instructions (specific attachments) that directs the wiring of the protocells that constitute the machine itself. To demonstrate the computing power of protocellular machines, we apply it to solve a NP-complete problem, known to be very demanding in computing power, the 3-SAT problem. We show how to program the assembly of a machine that can verify the satisfiability of a given boolean formula. Then we show how to use the massive parallelism of these machines to verify in less than 20 min all the valuations of the input variables and output a fluorescent signal when the formula is satisfiable or no signal at all otherwise.

  10. Manipulating novel quantum phenomena using synthetic gauge fields

    Science.gov (United States)

    Zhang, Shao-Liang; Zhou, Qi

    2017-11-01

    The past few years have seen fascinating progress in the creation and utilization of synthetic gauge fields for charge-neutral ultracold atoms. Whereas the synthesis of gauge fields in itself is readily interesting, it is more exciting to explore the new era that will be brought by the interplay between synthetic gauge fields and many other degrees of freedom of highly tunable ultracold atoms. This topical review surveys recent developments in using synthetic gauge fields to manipulate novel quantum phenomena that are not easy to access in other systems. We first summarize current experimental methods of creating synthetic gauge fields, including the use of Raman schemes, shaken lattices, and Raman-dressed lattices. We then discuss how synthetic gauge fields bring new physics to non-interacting systems, including degenerate single-particle ground states, quartic dispersions, topological band structures in lattices, and synthetic dimensions. As for interacting systems, we focus on novel quantum many-body states and quantum macroscopic phenomena induced by interactions in the presence of unconventional single-particle dispersions. For bosons, we discuss how a quartic dispersion leads to non-condensed bosonic states at low temperatures and at the ground state. For fermions, we discuss chiral superfluids in the presence of attractive s-wave interaction, where high partial-wave interactions are not required. Finally, we discuss the challenges in current experiments, and conclude with an outlook for what new exciting developments synthetic gauge fields may bring us in the near future.

  11. Challenges in enzymatic route of mannitol production.

    Science.gov (United States)

    Bhatt, Sheelendra Mangal; Mohan, Anand; Srivastava, Suresh Kumar

    2013-01-01

    Mannitol is an important biochemical often used as medicine and in food sector, yet its biotechnological is not preffered in Industry for large scale production, which may be due to the multistep mechanism involved in hydrogenation and reduction. This paper is a comparative preview covering present chemical and biotechnological approaches existing today for mannitol production at industrial scale. Biotechnological routes are suitable for adaptation at industrial level for mannitol production, and whatever concerns are there had been discussed in detail, namely, raw materials, broad range of enzymes with high activity at elevated temperature suitable for use in reactor, cofactor limitation, reduced by-product formation, end product inhibition, and reduced utilization of mannitol for enhancing the yield with maximum volumetric productivity.

  12. Synthetic strategies for controlling inter- and intramolecular interactions: Applications in single-molecule fluorescence imaging, bioluminescence imaging, and palladium catalysis

    Science.gov (United States)

    Conley, Nicholas R.

    The field of synthetic organic chemistry has reached such maturity that, with sufficient effort and resources, the synthesis of virtually any small molecule which exhibits reasonable stability at room temperature can be realized. While representing a monumental achievement for the field, the ability to exert precise control over molecular structure is just a means to an end, and it is frequently the responsibility of the synthetic chemist to determine which molecules should actually be synthesized. For better or worse, there exists no competitive free market in academia for new molecules, and as a result, the decision of which compounds should be synthesized is seldom driven by the forces of supply and demand; rather, it is guided by the synthetic chemist's interest in an anticipated structure-function relationship or in the properties of a previously unstudied class of molecules. As a consequence, there exists a pervasive need for chemists with synthetic expertise in fields (e.g., molecular imaging) and subdisciplines of chemistry (e.g., physical chemistry) in which the identification of promising synthetic targets dramatically outpaces the synthetic output in that field or subdiscipline, and ample opportunities are available for synthetic chemists who choose to pursue such cross-disciplinary research. This thesis describes synthetic efforts that leverage these opportunities to realize applications in biological imaging and in palladium catalysis. In Part I, the synthesis and characterization of three novel luminophores and their imaging applications are discussed. The first is a molecular beacon that utilizes a fluorophorefluorophore pair which exhibits H-dimer quenching in the closed conformation. This probe offers several advantages over conventional fluorophore-quencher molecular beacons in the detection of oligonucleotides, both in bulk and at the single-molecule level. Secondly, a fluorescent, Cy3-Cy5 covalent heterodimer is reported, which on account of the

  13. Synthetic Strategies for High Dielectric Constant Silicone Elastomers

    DEFF Research Database (Denmark)

    Madsen, Frederikke Bahrt

    synthetic strategies were developed in this Ph.D. thesis, in order to create silicone elastomers with high dielectric constants and thereby higher energy densities. The work focused on maintaining important properties such as dielectric loss, electrical breakdown strength and elastic modulus....... The methodology therefore involved chemically grafting high dielectric constant chemical groups onto the elastomer network, as this would potentially provide a stable elastomer system upon continued activation of the material. The first synthetic strategy involved the synthesis of a new type of cross...... extender’ that allowed for chemical modifications such as Cu- AAC. This route was promising for one-pot elastomer preparation and as a high dielectric constant additive to commercial silicone systems. The second approach used the borane-catalysed Piers-Rubinsztajn reaction to form spatially well...

  14. Production of synthetic hydrocarbon lube oil from highly waxy feedstocks

    Energy Technology Data Exchange (ETDEWEB)

    Xue, Q; Ding, Z; Zheng, Sh; Wu, W

    1980-01-01

    A feasible way to utilize the low value soft wax is to convert it into synthetic hydrocarbon lube oil by thermal cracking/polymerization route. The first commercial plant for this purpose has been in normal operation since 1970. It has been proved to be economically sound. The antioxidant response of the product polymer oil can be distinctly improved by hydro-refining. It has been found that the vacuum gas oil from highly waxy crude with or without furfural refining can be used as cracking stock. If high viscosity index polymer oil is desired, it is better to use slack wax as the cracking stock.

  15. Shortest Paths and Vehicle Routing

    DEFF Research Database (Denmark)

    Petersen, Bjørn

    This thesis presents how to parallelize a shortest path labeling algorithm. It is shown how to handle Chvátal-Gomory rank-1 cuts in a column generation context. A Branch-and-Cut algorithm is given for the Elementary Shortest Paths Problem with Capacity Constraint. A reformulation of the Vehicle...... Routing Problem based on partial paths is presented. Finally, a practical application of finding shortest paths in the telecommunication industry is shown....

  16. Slurry growth and gas retention in synthetic Hanford waste

    International Nuclear Information System (INIS)

    Bryan, S.A.; Pederson, L.R.; Scheele, R.D.

    1992-09-01

    This work seeks to establish chemical and physical processes responsible for the generation and retention of gases within waste from a particular high-level waste tank on the Hanford Site, Tank 101-SY, through the use of synthetic wastes on a laboratory scale. The goal of these activities is to support the development of mitigation/remediation strategies for Tank 101-SY. Laboratory studies of aged synthetic waste have shown that gas generation occurs thermally at a significant level at current tank temperatures. Gas compositions include the same gases produced in actual tank waste, primarily N 2 , N 2 O, and H 2 . Gas stoichiometries have been shown to be greatly influenced by several organic and inorganic constituents within the synthetic waste. Retention of gases in the synthetic waste is in the form of bubble attachment to solid particles

  17. Synthetic Biology and Personalized Medicine

    Science.gov (United States)

    Jain, K.K.

    2013-01-01

    Synthetic biology, application of synthetic chemistry to biology, is a broad term that covers the engineering of biological systems with structures and functions not found in nature to process information, manipulate chemicals, produce energy, maintain cell environment and enhance human health. Synthetic biology devices contribute not only to improve our understanding of disease mechanisms, but also provide novel diagnostic tools. Methods based on synthetic biology enable the design of novel strategies for the treatment of cancer, immune diseases metabolic disorders and infectious diseases as well as the production of cheap drugs. The potential of synthetic genome, using an expanded genetic code that is designed for specific drug synthesis as well as delivery and activation of the drug in vivo by a pathological signal, was already pointed out during a lecture delivered at Kuwait University in 2005. Of two approaches to synthetic biology, top-down and bottom-up, the latter is more relevant to the development of personalized medicines as it provides more flexibility in constructing a partially synthetic cell from basic building blocks for a desired task. PMID:22907209

  18. New routes of allergen immunotherapy.

    Science.gov (United States)

    Aricigil, Mitat; Muluk, Nuray Bayar; Sakarya, Engin Umut; Sakalar, Emine Güven; Senturk, Mehmet; Reisacher, William R; Cingi, Cemal

    2016-11-01

    Allergen immunotherapy is the only cure for immunoglobulin E mediated type I respiratory allergies. Subcutaneous immunotherapy (SCIT) and sublingual immunotherapy (SLIT) are the most common treatments. In this article, we reviewed new routes of allergen immunotherapy. Data on alternative routes to allow intralymphatic immunotherapy (ILIT), epicutaneous immunotherapy (EPIT), local nasal immunotherapy (LNIT), oral immunotherapy (OIT), and oral mucosal immunotherapy (OMIT) were gathered from the literature and were discussed. ILIT features direct injection of allergens into lymph nodes. ILIT may be clinically effective after only a few injections and induces allergen-specific immunoglobulin G, similarly to SCIT. A limitation of ILIT is that intralymphatic injections are required. EPIT features allergen administration by using patches mounted on the skin. EPIT seeks to target epidermal antigen-presenting Langerhans cells rather than mast cells or the vasculature; this should reduce both local and systemic adverse effects. LNIT involves the spraying of allergen extracts into the nasal cavity. Natural or chemically modified allergens (the latter, termed allergoids, lack immunoglobulin E reactivity) are prepared in a soluble form. OIT involves the regular administration of small amounts of a food allergen by mouth and commences with low oral doses, which are then increased as tolerance develops. OMIT seeks to deliver allergenic proteins to an expanded population of Langerhans cells in the mucosa of the oral cavity. ILIT, EPIT, LNIT, OIT, and OMIT are new routes for allergen immunotherapy. They are safe and effective.

  19. Cultural Routes and Intangible Heritage

    Directory of Open Access Journals (Sweden)

    Enza Zabbini

    2012-08-01

    Full Text Available The theoretical interpretation of thematic routes helps to predict the effects on the territories visited by cultured tourists who want to enrich their cultural and emotional baggage. After the analysis of some interpretations, this paper will examine how the practical implementation of an itinerary approved by the Council of Europe has evolved over the years. And it will also reflect on the practical results in the areas involved in that project. "The Hannibal Pathway ", the main overland walk on the "Phoenician Route - Cultural Route recognized by the Council of Europe" – represents a case of study that allows to reflect over the impact of cultural tourism based on immaterial heritage. In fact, in the areas where the battle of 21 June 217 BC took place, nothing tangible is left, except the landscape that has kept its conformation intact. In these areas, thanks to the foresight of the local governments in the last three decades, the landscape of the plain has been preserved. This makes possible today to propose an historical path precisely based on the landscape and on the new techniques for the valorization of the heritage. In the Tuoro plain it is possible to see the battlefields, thus retracing the various stages of the battle, supported by the Documentation Centre of the Capra Palace and virtual reconstructions of high technical quality.

  20. VANET Routing Protocols: Pros and Cons

    OpenAIRE

    Paul, Bijan; Ibrahim, Md.; Bikas, Md. Abu Naser

    2012-01-01

    VANET (Vehicular Ad-hoc Network) is a new technology which has taken enormous attention in the recent years. Due to rapid topology changing and frequent disconnection makes it difficult to design an efficient routing protocol for routing data among vehicles, called V2V or vehicle to vehicle communication and vehicle to road side infrastructure, called V2I. The existing routing protocols for VANET are not efficient to meet every traffic scenarios. Thus design of an efficient routing protocol h...

  1. Routing Data Authentication in Wireless Networks; TOPICAL

    International Nuclear Information System (INIS)

    TORGERSON, MARK D.; VAN LEEUWEN, BRIAN P.

    2001-01-01

    In this paper, we discuss several specific threats directed at the routing data of an ad hoc network. We address security issues that arise from wrapping authentication mechanisms around ad hoc routing data. We show that this bolt-on approach to security may make certain attacks more difficult, but still leaves the network routing data vulnerable. We also show that under a certain adversarial model, most existing routing protocols cannot be secured with the aid of digital signatures

  2. Synthetic Biology: Advancing Biological Frontiers by Building Synthetic Systems

    OpenAIRE

    Chen, Yvonne Yu-Hsuan; Galloway, Kate E; Smolke, Christina D

    2012-01-01

    Advances in synthetic biology are contributing to diverse research areas, from basic biology to biomanufacturing and disease therapy. We discuss the theoretical foundation, applications, and potential of this emerging field.

  3. Developing an eco-routing application.

    Science.gov (United States)

    2014-01-01

    The study develops eco-routing algorithms and investigates and quantifies the system-wide impacts of implementing an eco-routing system. Two eco-routing algorithms are developed: one based on vehicle sub-populations (ECO-Subpopulation Feedback Assign...

  4. Is Entrepreneurship a Route Out of Deprivation?

    DEFF Research Database (Denmark)

    Frankish, Julian S.; Roberts, Richard G.; Coad, Alexander Jean-Luc

    2014-01-01

    Frankish J. S., Roberts R. G., Coad A. and Storey D. J. Is entrepreneurship a route out of deprivation?, Regional Studies. This paper investigates whether entrepreneurship constitutes a route out of deprivation for those living in deprived areas. The measure of income/wealth used is based...... the wealth distribution. Hence, entrepreneurship can be a route out of deprivation....

  5. The Pyramidal Capacitated Vehicle Routing Problem

    DEFF Research Database (Denmark)

    Lysgaard, Jens

    This paper introduces the Pyramidal Capacitated Vehicle Routing Problem (PCVRP) as a restricted version of the Capacitated Vehicle Routing Problem (CVRP). In the PCVRP each route is required to be pyramidal in a sense generalized from the Pyramidal Traveling Salesman Problem (PTSP). A pyramidal...

  6. The pyramidal capacitated vehicle routing problem

    DEFF Research Database (Denmark)

    Lysgaard, Jens

    2010-01-01

    This paper introduces the pyramidal capacitated vehicle routing problem (PCVRP) as a restricted version of the capacitated vehicle routing problem (CVRP). In the PCVRP each route is required to be pyramidal in a sense generalized from the pyramidal traveling salesman problem (PTSP). A pyramidal...

  7. Approaches to chemical synthetic biology.

    Science.gov (United States)

    Chiarabelli, Cristiano; Stano, Pasquale; Anella, Fabrizio; Carrara, Paolo; Luisi, Pier Luigi

    2012-07-16

    Synthetic biology is first represented in terms of two complementary aspects, the bio-engineering one, based on the genetic manipulation of extant microbial forms in order to obtain forms of life which do not exist in nature; and the chemical synthetic biology, an approach mostly based on chemical manipulation for the laboratory synthesis of biological structures that do not exist in nature. The paper is mostly devoted to shortly review chemical synthetic biology projects currently carried out in our laboratory. In particular, we describe: the minimal cell project, then the "Never Born Proteins" and lastly the Never Born RNAs. We describe and critically analyze the main results, emphasizing the possible relevance of chemical synthetic biology for the progress in basic science and biotechnology. Copyright © 2012 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.

  8. Synthetic Biology for Specialty Chemicals.

    Science.gov (United States)

    Markham, Kelly A; Alper, Hal S

    2015-01-01

    In this review, we address recent advances in the field of synthetic biology and describe how those tools have been applied to produce a wide variety of chemicals in microorganisms. Here we classify the expansion of the synthetic biology toolbox into three different categories based on their primary function in strain engineering-for design, for construction, and for optimization. Next, focusing on recent years, we look at how chemicals have been produced using these new synthetic biology tools. Advances in producing fuels are briefly described, followed by a more thorough treatment of commodity chemicals, specialty chemicals, pharmaceuticals, and nutraceuticals. Throughout this review, an emphasis is placed on how synthetic biology tools are applied to strain engineering. Finally, we discuss organism and host strain diversity and provide a future outlook in the field.

  9. Is synthetic biology mechanical biology?

    Science.gov (United States)

    Holm, Sune

    2015-12-01

    A widespread and influential characterization of synthetic biology emphasizes that synthetic biology is the application of engineering principles to living systems. Furthermore, there is a strong tendency to express the engineering approach to organisms in terms of what seems to be an ontological claim: organisms are machines. In the paper I investigate the ontological and heuristic significance of the machine analogy in synthetic biology. I argue that the use of the machine analogy and the aim of producing rationally designed organisms does not necessarily imply a commitment to mechanical biology. The ideal of applying engineering principles to biology is best understood as expressing recognition of the machine-unlikeness of natural organisms and the limits of human cognition. The paper suggests an interpretation of the identification of organisms with machines in synthetic biology according to which it expresses a strategy for representing, understanding, and constructing living systems that are more machine-like than natural organisms.

  10. Adaptive Synthetic Forces: Situation Awareness

    National Research Council Canada - National Science Library

    Hill, Randall

    2001-01-01

    ...: perception, comprehension, and prediction. Building on these ideas, we developed techniques for improving the situation awareness in synthetic helicopter pilots for the ModSAF military simulation by giving them more human-like perception...

  11. Programming languages for synthetic biology.

    Science.gov (United States)

    Umesh, P; Naveen, F; Rao, Chanchala Uma Maheswara; Nair, Achuthsankar S

    2010-12-01

    In the backdrop of accelerated efforts for creating synthetic organisms, the nature and scope of an ideal programming language for scripting synthetic organism in-silico has been receiving increasing attention. A few programming languages for synthetic biology capable of defining, constructing, networking, editing and delivering genome scale models of cellular processes have been recently attempted. All these represent important points in a spectrum of possibilities. This paper introduces Kera, a state of the art programming language for synthetic biology which is arguably ahead of similar languages or tools such as GEC, Antimony and GenoCAD. Kera is a full-fledged object oriented programming language which is tempered by biopart rule library named Samhita which captures the knowledge regarding the interaction of genome components and catalytic molecules. Prominent feature of the language are demonstrated through a toy example and the road map for the future development of Kera is also presented.

  12. The Silk Route from Land to Sea

    Directory of Open Access Journals (Sweden)

    Jack Weatherford

    2018-04-01

    Full Text Available The Silk Route reached its historic and economic apogee under the Mongol Empire (1207–1368, as a direct result of the policies of Chinggis Khan (Genghis Khan and his successors. Because the land network proved inefficient for the amount of goods needing transport from one part of the empire to another, the Mongols expanded the Silk Route to ocean shipping and thus created the first Maritime Silk Route. The sea traffic initially expanded the land routes but soon strangled them. With the expansion of the Maritime Silk Route through the fourteenth century, the land connections reverted to local networks and lost their global importance.

  13. Luminescence response of synthetic opal under femtosecond laser pumping

    International Nuclear Information System (INIS)

    Vasnetsov, M.V.; Bazhenov, V.Yu.; Dmitruk, I.N.; Kudryavtseva, A.D.; Tcherniega, N.V.

    2015-01-01

    Synthetic opal is an artificial photonic metamaterial composed from spherical globules of amorphous silica (SiO 2 ) about 300 nm in diameter. We report, for the first time to our knowledge, the origin of a narrow luminescence spectral peak (4 nm HWHM) and optical second and third harmonic generation in synthetic opal samples under femtosecond laser excitation (800 nm) at liquid-nitrogen temperature. Stimulated-emission effects are discussed related to the possibility of nanocavity lasing at the condition of the first Mie resonance in a dielectric sphere. - Highlights: • Second harmonic generation in a synthetic opal (amorphous material composed from spherical SiO 2 globules) was observed. • Narrow luminescence peak which we assign to a Mie resonance in a globule was detected at liquid-nitrogen temperature

  14. A Genetic Algorithm on Inventory Routing Problem

    Directory of Open Access Journals (Sweden)

    Nevin Aydın

    2014-03-01

    Full Text Available Inventory routing problem can be defined as forming the routes to serve to the retailers from the manufacturer, deciding on the quantity of the shipment to the retailers and deciding on the timing of the replenishments. The difference of inventory routing problems from vehicle routing problems is the consideration of the inventory positions of retailers and supplier, and making the decision accordingly. Inventory routing problems are complex in nature and they can be solved either theoretically or using a heuristics method. Metaheuristics is an emerging class of heuristics that can be applied to combinatorial optimization problems. In this paper, we provide the relationship between vendor-managed inventory and inventory routing problem. The proposed genetic for solving vehicle routing problem is described in detail.

  15. An overview of the key routes to the best selling 5-membered ring heterocyclic pharmaceuticals

    Directory of Open Access Journals (Sweden)

    Nikzad Nikbin

    2011-04-01

    Full Text Available This review presents a comprehensive overview on selected synthetic routes towards commercial drug compounds as published in both journal and patent literature. Owing to the vast number of potential structures, we have concentrated only on those drugs containing five-membered heterocycles and focused principally on the assembly of the heterocyclic core. In order to target the most representative chemical entities the examples discussed have been selected from the top 200 best selling drugs of recent years.

  16. Freedom and Responsibility in Synthetic Genomics: The Synthetic Yeast Project.

    Science.gov (United States)

    Sliva, Anna; Yang, Huanming; Boeke, Jef D; Mathews, Debra J H

    2015-08-01

    First introduced in 2011, the Synthetic Yeast Genome (Sc2.0) PROJECT is a large international synthetic genomics project that will culminate in the first eukaryotic cell (Saccharomyces cerevisiae) with a fully synthetic genome. With collaborators from across the globe and from a range of institutions spanning from do-it-yourself biology (DIYbio) to commercial enterprises, it is important that all scientists working on this project are cognizant of the ethical and policy issues associated with this field of research and operate under a common set of principles. In this commentary, we survey the current ethics and regulatory landscape of synthetic biology and present the Sc2.0 Statement of Ethics and Governance to which all members of the project adhere. This statement focuses on four aspects of the Sc2.0 PROJECT: societal benefit, intellectual property, safety, and self-governance. We propose that such project-level agreements are an important, valuable, and flexible model of self-regulation for similar global, large-scale synthetic biology projects in order to maximize the benefits and minimize potential harms. Copyright © 2015 by the Genetics Society of America.

  17. Fusion: an energy source for synthetic fuels

    International Nuclear Information System (INIS)

    Fillo, J.A.; Powell, J; Steinberg, M.

    1980-01-01

    The decreasing availability of fossil fuels emphasizes the need to develop systems which will produce synthetic fuel to substitute for and supplement the natural supply. An important first step in the synthesis of liquid and gaseous fuels is the production of hydrogen. Thermonuclear fusion offers an inexhaustible source of energy for the production of hydrogen from water. Depending on design, electric generation efficiencies of approx. 40 to 60% and hydrogen production efficiencies by high temperature electrolysis of approx. 50 to 70% are projected for fusion reactors using high temperature blankets. Fusion/coal symbiotic systems appear economically promising for the first generation of commercial fusion synfuels plants. Coal production requirements and the environmental effects of large-scale coal usage would be greatly reduced by a fusion/coal system. In the long term, there could be a gradual transition to an inexhaustible energy system based solely on fusion

  18. Load Balancing Routing with Bounded Stretch

    Directory of Open Access Journals (Sweden)

    Chen Siyuan

    2010-01-01

    Full Text Available Routing in wireless networks has been heavily studied in the last decade. Many routing protocols are based on classic shortest path algorithms. However, shortest path-based routing protocols suffer from uneven load distribution in the network, such as crowed center effect where the center nodes have more load than the nodes in the periphery. Aiming to balance the load, we propose a novel routing method, called Circular Sailing Routing (CSR, which can distribute the traffic more evenly in the network. The proposed method first maps the network onto a sphere via a simple stereographic projection, and then the route decision is made by a newly defined "circular distance" on the sphere instead of the Euclidean distance in the plane. We theoretically prove that for a network, the distance traveled by the packets using CSR is no more than a small constant factor of the minimum (the distance of the shortest path. We also extend CSR to a localized version, Localized CSR, by modifying greedy routing without any additional communication overhead. In addition, we investigate how to design CSR routing for 3D networks. For all proposed methods, we conduct extensive simulations to study their performances and compare them with global shortest path routing or greedy routing in 2D and 3D wireless networks.

  19. Meeting Report: Synthetic Biology Jamboree for Undergraduates

    Science.gov (United States)

    Campbell, A. Malcolm

    2005-01-01

    The field of synthetic biology (the name is derived from an analogy to synthetic chemistry) has recognized itself as a "field" only since about 2002. Synthetic biology has gotten some high-profile attention recently, but most people are not aware the field even exists. Synthetic biologists apply engineering principles to genomic circuits to…

  20. Synthetic biology, metaphors and responsibility.

    Science.gov (United States)

    McLeod, Carmen; Nerlich, Brigitte

    2017-08-29

    Metaphors are not just decorative rhetorical devices that make speech pretty. They are fundamental tools for thinking about the world and acting on the world. The language we use to make a better world matters; words matter; metaphors matter. Words have consequences - ethical, social and legal ones, as well as political and economic ones. They need to be used 'responsibly'. They also need to be studied carefully - this is what we want to do through this editorial and the related thematic collection. In the context of synthetic biology, natural and social scientists have become increasingly interested in metaphors, a wave of interest that we want to exploit and amplify. We want to build on emerging articles and books on synthetic biology, metaphors of life and the ethical and moral implications of such metaphors. This editorial provides a brief introduction to synthetic biology and responsible innovation, as well as a comprehensive review of literature on the social, cultural and ethical impacts of metaphor use in genomics and synthetic biology. Our aim is to stimulate an interdisciplinary and international discussion on the impact that metaphors can have on science, policy and publics in the context of synthetic biology.

  1. Content metamorphosis in synthetic holography

    International Nuclear Information System (INIS)

    Desbiens, Jacques

    2013-01-01

    A synthetic hologram is an optical system made of hundreds of images amalgamated in a structure of holographic cells. Each of these images represents a point of view on a three-dimensional space which makes us consider synthetic holography as a multiple points of view perspective system. In the composition of a computer graphics scene for a synthetic hologram, the field of view of the holographic image can be divided into several viewing zones. We can attribute these divisions to any object or image feature independently and operate different transformations on image content. In computer generated holography, we tend to consider content variations as a continuous animation much like a short movie. However, by composing sequential variations of image features in relation with spatial divisions, we can build new narrative forms distinct from linear cinematographic narration. When observers move freely and change their viewing positions, they travel from one field of view division to another. In synthetic holography, metamorphoses of image content are within the observer's path. In all imaging Medias, the transformation of image features in synchronisation with the observer's position is a rare occurrence. However, this is a predominant characteristic of synthetic holography. This paper describes some of my experimental works in the development of metamorphic holographic images.

  2. Control theory meets synthetic biology.

    Science.gov (United States)

    Del Vecchio, Domitilla; Dy, Aaron J; Qian, Yili

    2016-07-01

    The past several years have witnessed an increased presence of control theoretic concepts in synthetic biology. This review presents an organized summary of how these control design concepts have been applied to tackle a variety of problems faced when building synthetic biomolecular circuits in living cells. In particular, we describe success stories that demonstrate how simple or more elaborate control design methods can be used to make the behaviour of synthetic genetic circuits within a single cell or across a cell population more reliable, predictable and robust to perturbations. The description especially highlights technical challenges that uniquely arise from the need to implement control designs within a new hardware setting, along with implemented or proposed solutions. Some engineering solutions employing complex feedback control schemes are also described, which, however, still require a deeper theoretical analysis of stability, performance and robustness properties. Overall, this paper should help synthetic biologists become familiar with feedback control concepts as they can be used in their application area. At the same time, it should provide some domain knowledge to control theorists who wish to enter the rising and exciting field of synthetic biology. © 2016 The Author(s).

  3. Cerium oxide for the destruction of chemical warfare agents: A comparison of synthetic routes

    Czech Academy of Sciences Publication Activity Database

    Janos, P.; Henych, Jiří; Pelant, O.; Pilařová, V.; Vrtoch, L.; Kormunda, M.; Mazanec, K.; Štengl, Václav

    2016-01-01

    Roč. 304, MAR (2016), s. 259-268 ISSN 0304-3894 Institutional support: RVO:61388980 Keywords : Cerium oxide * Chemical warfare agents * Organophosphate compounds * Decontamination Subject RIV: CA - Inorganic Chemistry Impact factor: 6.065, year: 2016

  4. Synthetic routes to degradable copolymers deriving from the biosynthesized polyhydroxyalkanoates: A mini review

    Directory of Open Access Journals (Sweden)

    Y. Ke

    2016-01-01

    Full Text Available Polyhydroxyalkanoates are a family of natural polyesters being produced as intracellular carbon and energy reserves by a wide variety of microorganisms. They have developed rapidly in both research and development efforts globally in the last 15 years. Till now, over 100 different types of PHAs have been successfully biosynthesized using both genetic engineering and fermentation techniques. Their unique biodegradable, biocompatible and thermoplastic characteristics make PHAs promising candidates for the commodity and biomedical applications. This review focused on the chemical synthesis of the derivatives of the biosynthesized PHAs.

  5. Guanylation of thiosemicarbazones: a new synthetic route to polysubstituted guanylhydrazones with antimicrobial activity

    International Nuclear Information System (INIS)

    Cunha, Silvio; Macedo Junior, Fernando Cesar de; Costa, Giselle A.N.; Neves, Daniela C.; Souza Neta, Lourdes Cardoso de

    2009-01-01

    Thiosemicarbazones were employed for the first time as electrophiles in the guanylation reaction promoted by HgCl 2 , affording polysubstituted guanylhydrazones, with regioselective introduction of each nitrogen substituent. The antibacterial and antifungal activities of guanylhydrazones were evaluated by determination of minimal inhibitory concentrations. Some of them exhibited very low minimal inhibitory concentrations (MIC) and broad-spectrum activities. The configurations of two guanylhydrazones were assigned by X-ray analysis that also revealed intramolecular interactions of the type N-H...N and C-H...N. (author)

  6. Determining Synthetic Routes to Consumer Product Ingredients through the Use of Electronic Resources

    Science.gov (United States)

    Love, Brian E.; Bennett, Lisa J.

    2016-01-01

    An activity is described in which students in the first semester of a two semester organic chemistry laboratory class are introduced to the use of SciFinder. Students are required to determine the structures of three compounds as well as additional information regarding the synthesis of one of them using some of the features available in SciFinder.

  7. Detection, isolation and characterization of principle synthetic route indicative impurity in telmisartan

    Directory of Open Access Journals (Sweden)

    V. Srinivasan

    2016-11-01

    Full Text Available An unknown impurity was detected in the telmisartan bulk drug (active pharmaceutical ingredient – API using an isocratic reversed-phase high performance liquid chromatography (HPLC. This impurity was isolated by preparative HPLC. Spectral data of the isolated impurity were collected. Based on the spectral data deriving from two dimensional nuclear magnetic spectroscopy (2D-NMR and mass spectrometry (MS, the impurity was characterized as “methyl 4′,4′-dibromo methyl biphenyl-2-carboxylate”. The arrived structure was further confirmed by theoretical studies.

  8. Consecutive native chemical ligation-route to synthetic mouse prion protein

    Czech Academy of Sciences Publication Activity Database

    Zawada, Zbigniew; Šebestík, Jaroslav; Šafařík, Martin; Březinová, Anna; Bouř, Petr; Hlaváček, Jan; Stibor, Ivan

    2009-01-01

    Roč. 103, č. 11 (2009), s. 1001-1001 ISSN 0009-2770. [Pokroky v organické, bioorganické a farmaceutické chemii /44./. 27.11.2009-29.11.2009, Liblice] R&D Projects: GA ČR GA203/07/1517 Institutional research plan: CEZ:AV0Z40550506 Keywords : prion * chemical ligation Subject RIV: CC - Organic Chemistry

  9. A facile synthetic route to poly(p-phenylene terephthalamide) with dual functional groups.

    Science.gov (United States)

    Du, Shuming; Wang, Wenbin; Yan, Yan; Zhang, Jie; Tian, Ming; Zhang, Liqun; Wan, Xinhua

    2014-09-07

    Claisen rearrangement reaction was employed for the first time to obtain a novel PPTA bearing reactive allyl and hydroxyl groups which may act as a sizing agent of Kevlar fibers to improve the interface structure and interfacial adhesion of rubber or epoxy based composites.

  10. HIGHLY FLEXIBLE SYNTHETIC ROUTES TO FUNCTIONALIZED PHOSPHOLANES FROM CARBOHYDRATES. (R826120)

    Science.gov (United States)

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  11. Heterocyclic Nanographenes and Other Polycyclic Heteroaromatic Compounds: Synthetic Routes, Properties, and Applications.

    Science.gov (United States)

    Stępień, Marcin; Gońka, Elżbieta; Żyła, Marika; Sprutta, Natasza

    2017-02-22

    Two-dimensionally extended, polycyclic heteroaromatic molecules (heterocyclic nanographenes) are a highly versatile class of organic materials, applicable as functional chromophores and organic semiconductors. In this Review, we discuss the rich chemistry of large heteroaromatics, focusing on their synthesis, electronic properties, and applications in materials science. This Review summarizes the historical development and current state of the art in this rapidly expanding field of research, which has become one of the key exploration areas of modern heterocyclic chemistry.

  12. A conversion of aromatic thiocyanates into sulfothioates: new synthetic route to aromatic Bunte salts

    Czech Academy of Sciences Publication Activity Database

    Jansa, Petr; Čechová, Lucie; Dračínský, Martin; Janeba, Zlatko

    2013-01-01

    Roč. 3, č. 8 (2013), s. 2650-2654 ISSN 2046-2069 R&D Projects: GA MV VG20102015046 Institutional support: RVO:61388963 Keywords : functionalized gold nanoparticles * self -assembled monolayers * thiosulfates * disulfides Subject RIV: CC - Organic Chemistry Impact factor: 3.708, year: 2013

  13. Synthetic routes contaminate graphene materials with a whole spectrum of unanticipated metallic elements

    Czech Academy of Sciences Publication Activity Database

    Wong, C. H. A.; Sofer, Z.; Kubešová, Marie; Kučera, Jan; Matějková, Stanislava; Pumera, M.

    2014-01-01

    Roč. 111, č. 38 (2014), s. 13774-13779 ISSN 0027-8424 R&D Projects: GA ČR(CZ) GBP108/12/G108; GA MŠk(XE) LM2011019 Institutional support: RVO:61389005 ; RVO:61388963 Keywords : carbon nanotubes * chemical reduction * doped graphene Subject RIV: BM - Solid Matter Physics ; Magnetism; CF - Physical ; Theoretical Chemistry (UOCHB-X) Impact factor: 9.674, year: 2014

  14. New synthetic routes to polyoxometalate containing ionic liquids an investigation of their properties

    CERN Document Server

    Herrmann, Sven

    2015-01-01

    In his Master project Sven Herrmann for the first time carried out fundamental investigations into the development of polyoxometalate based ionic liquids (POM-ILs). The POM-ILs were obtained by charge balancing inorganic polyoxometalate (POM) anions with sterically demanding tetraalkylammonium or tetraalkylphosphonium cations. By functionalization of lacunary Keggin clusters with 3d-transition metals and charge balancing with tetraalkylammonium cations of differing chain length, a model system for the correlation of the molecular structure with macroscopic materials properties was obtained. In

  15. Vehicle routing problem in investment fund allocation

    Science.gov (United States)

    Mamat, Nur Jumaadzan Zaleha; Jaaman, Saiful Hafizah; Ahmad, Rokiah Rozita; Mohd, Ismail

    2013-04-01

    Since its introduction by Dantzig and Ramser in 1959, vehicle routing problem keeps evolving in theories, applications and variability. The evolution in computing and technology are also important contributors to research in solving vehicle routing problem. The main sectors of interests among researchers and practitioners for vehicle routing problem are transportation, distribution and logistics. However, literature found that concept and benefits of vehicle routing problem are not taken advantages of by researchers in the field of investment. Other methods found used in investment include multi-objective programming, linear programming, goal programming and integer programming. Yet the application of vehicle routing problem is not fully explored. A proposal on a framework of the fund allocation optimization using vehicle routing problem is presented here. Preliminary results using FTSE Bursa Malaysia data testing the framework are also given.

  16. Zone routing in a torus network

    Science.gov (United States)

    Chen, Dong; Heidelberger, Philip; Kumar, Sameer

    2013-01-29

    A system for routing data in a network comprising a network logic device at a sending node for determining a path between the sending node and a receiving node, wherein the network logic device sets one or more selection bits and one or more hint bits within the data packet, a control register for storing one or more masks, wherein the network logic device uses the one or more selection bits to select a mask from the control register and the network logic device applies the selected mask to the hint bits to restrict routing of the data packet to one or more routing directions for the data packet within the network and selects one of the restricted routing directions from the one or more routing directions and sends the data packet along a link in the selected routing direction toward the receiving node.

  17. Predicting transportation routes for radioactive wastes

    International Nuclear Information System (INIS)

    Joy, D.S.; Johnson, P.E.; Clarke, D.B.; McGuire, S.C.

    1981-01-01

    Oak Ridge National Laboratory (ORNL) has been involved in transportation logistics of radioactive wastes as part of the overall waste transportation program. A Spent Fuel Logistics Model (SFLM), was developed to predict overall material balances representing the flow of spent fuel assemblies from reactors to away-from-reactor storage facilities and/or to federal repositories. The transportation requirements to make these shipments are also itemized. The next logical step in the overall transportation project was the development of a set of computer codes which would predict likely transportation routes for waste shipments. Two separate routing models are now operational at ORNL. Routes for truck transport can be estimated with the HIGHWAY program, and rail and barge routes can be predicted with the INTERLINE model. This paper discusses examples of the route estimates and applications of the routing models

  18. Risk assessment of alternative proliferation routes

    International Nuclear Information System (INIS)

    Ahmed, S.; Husseiny, A.A.

    1982-01-01

    Multi-Attribute Decision Theory is applied to rank II alternative routes to nuclear proliferation in order of difficulty in acquiring nuclear weapons by nonnuclear countries. The method is based on reducing the various variables affecting the decision to a single function providing a measure for the proliferation route. The results indicate that the most difficult route to obtain atomic weapons is through nuclear power reactors, specifically the liquid-metal fast breeder reactor, heavy water Canada deuterium uranium reactor, and light water reactors such as boiling water and pressurized water reactors. The easiest routes are supercritical centrifuge isotope separation, laser isotope separation, and research reactor. However, nonnuclear routes available that result in substantial damage to life and property are easier than any nuclear route

  19. Soft chemistry routes to GeS2 nanoparticles

    Science.gov (United States)

    Courthéoux, Laurence; Mathiaud, Romain; Ribes, Michel; Pradel, Annie

    2018-04-01

    Spherical GeS2 particles are prepared by a low temperature liquid route with TEOG as germanium precursor and either H2S or thioacetamide (TAA) as sulfur precursors. The size and agglomeration of the particles change depending upon the temperature and nature of the solvent. Most synthesis lead to preparing amorphous GeS2. When the reaction kinetic is slowed down by using TAA at 25 °C, the obtained GeS2 product presents a larger order in the range of few Å as proven by Raman spectroscopy, even though it is still an amorphous compound as suggested by X-Ray diffraction and TEM experiments.

  20. Microfluidic Technologies for Synthetic Biology

    Directory of Open Access Journals (Sweden)

    Sung Kuk Lee

    2011-06-01

    Full Text Available Microfluidic technologies have shown powerful abilities for reducing cost, time, and labor, and at the same time, for increasing accuracy, throughput, and performance in the analysis of biological and biochemical samples compared with the conventional, macroscale instruments. Synthetic biology is an emerging field of biology and has drawn much attraction due to its potential to create novel, functional biological parts and systems for special purposes. Since it is believed that the development of synthetic biology can be accelerated through the use of microfluidic technology, in this review work we focus our discussion on the latest microfluidic technologies that can provide unprecedented means in synthetic biology for dynamic profiling of gene expression/regulation with high resolution, highly sensitive on-chip and off-chip detection of metabolites, and whole-cell analysis.

  1. Synthetic neurosteroids on brain protection

    Directory of Open Access Journals (Sweden)

    Mariana Rey

    2015-01-01

    Full Text Available Neurosteroids, like allopregnanolone and pregnanolone, are endogenous regulators of neuronal excitability. Inside the brain, they are highly selective and potent modulators of GABA A receptor activity. Their anticonvulsant, anesthetics and anxiolytic properties are useful for the treatments of several neurological and psychiatric disorders via reducing the risks of side effects obtained with the commercial drugs. The principal disadvantages of endogenous neurosteroids administration are their rapid metabolism and their low oral bioavailability. Synthetic steroids analogues with major stability or endogenous neurosteroids stimulation synthesis might constitute promising novel strategies for the treatment of several disorders. Numerous studies indicate that the 3α-hydroxyl configuration is the key for binding and activity, but modifications in the steroid nucleus may emphasize different pharmacophores. So far, several synthetic steroids have been developed with successful neurosteroid-like effects. In this work, we summarize the properties of various synthetic steroids probed in trials throughout the analysis of several neurosteroids-like actions.

  2. Sinkhole Avoidance Routing in Wireless Sensor Networks

    Science.gov (United States)

    2011-05-09

    COVERED (From- To) 09-05-2011 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER Sinkhole Avoidance Routing in Wireless Sensor Networks 5b . GRANT NUMBER . 5c...reliability of wireless sensor networks. 15. SUBJECT TERMS wireless sensor networks, sinkhole attack, routing protocol 16. SECURITY CLASSIFICATION...Include area code) Standard Form 298 (Rev. 8/98) Prescribed by ANSI Std . Z39.18 1 Sinkhole Avoidance Routing in Wireless Sensor Networks MIDN 1/C

  3. A joint routing and speed optimization problem

    OpenAIRE

    Fukasawa, Ricardo; He, Qie; Santos, Fernando; Song, Yongjia

    2016-01-01

    Fuel cost contributes to a significant portion of operating cost in cargo transportation. Though classic routing models usually treat fuel cost as input data, fuel consumption heavily depends on the travel speed, which has led to the study of optimizing speeds over a given fixed route. In this paper, we propose a joint routing and speed optimization problem to minimize the total cost, which includes the fuel consumption cost. The only assumption made on the dependence between the fuel cost an...

  4. Synthetic biology as red herring.

    Science.gov (United States)

    Preston, Beth

    2013-12-01

    It has become commonplace to say that with the advent of technologies like synthetic biology the line between artifacts and living organisms, policed by metaphysicians since antiquity, is beginning to blur. But that line began to blur 10,000 years ago when plants and animals were first domesticated; and has been thoroughly blurred at least since agriculture became the dominant human subsistence pattern many millennia ago. Synthetic biology is ultimately only a late and unexceptional offshoot of this prehistoric development. From this perspective, then, synthetic biology is a red herring, distracting us from more thorough philosophical consideration of the most truly revolutionary human practice-agriculture. In the first section of this paper I will make this case with regard to ontology, arguing that synthetic biology crosses no ontological lines that were not crossed already in the Neolithic. In the second section I will construct a parallel case with regard to cognition, arguing that synthetic biology as biological engineering represents no cognitive advance over what was required for domestication and the new agricultural subsistence pattern it grounds. In the final section I will make the case with regard to human existence, arguing that synthetic biology, even if wildly successful, is not in a position to cause significant existential change in what it is to be human over and above the massive existential change caused by the transition to agriculture. I conclude that a longer historical perspective casts new light on some important issues in philosophy of technology and environmental philosophy. Copyright © 2013 Elsevier Ltd. All rights reserved.

  5. US Competitiveness in Synthetic Biology.

    Science.gov (United States)

    Gronvall, Gigi Kwik

    2015-01-01

    Synthetic biology is an emerging technical field that aims to make biology easier to engineer; the field has applications in strategically important sectors for the US economy. While the United States currently leads in synthetic biology R&D, other nations are heavily investing in order to boost their economies, which will inevitably diminish the US leadership position. This outcome is not entirely negative--additional investments will expand markets--but it is critical that the US government take steps to remain competitive: There are applications from which the US population and economy may benefit; there are specific applications with importance for national defense; and US technical leadership will ensure that US experts have a leading role in synthetic biology governance, regulation, and oversight. Measures to increase competitiveness in S&T generally are broadly applicable for synthetic biology and should be pursued. However, the US government will also need to take action on fundamental issues that will affect the field's development, such as countering anti-GMO (genetically modified organism) sentiments and anti-GMO legislation. The United States should maintain its regulatory approach so that it is the product that is regulated, not the method used to create a product. At the same time, the United States needs to ensure that the regulatory framework is updated so that synthetic biology products do not fall into regulatory gaps. Finally, the United States needs to pay close attention to how synthetic biology applications may be governed internationally, such as through the Nagoya Protocol of the Convention on Biological Diversity, so that beneficial applications may be realized.

  6. Reconstruction of recycling flux from synthetic camera images, evaluated for the Wendelstein 7-X startup limiter

    Science.gov (United States)

    Frerichs, H.; Effenberg, F.; Feng, Y.; Schmitz, O.; Stephey, L.; Reiter, D.; Börner, P.; The W7-X Team

    2017-12-01

    The interpretation of spectroscopic measurements in the edge region of high-temperature plasmas can be guided by modeling with the EMC3-EIRENE code. A versatile synthetic diagnostic module, initially developed for the generation of synthetic camera images, has been extended for the evaluation of the inverse problem in which the observable photon flux is related back to the originating particle flux (recycling). An application of this synthetic diagnostic to the startup phase (inboard) limiter in Wendelstein 7-X (W7-X) is presented, and reconstruction of recycling from synthetic observation of \\renewcommand{\

  7. Synthetic Phage for Tissue Regeneration

    Directory of Open Access Journals (Sweden)

    So Young Yoo

    2014-01-01

    Full Text Available Controlling structural organization and signaling motif display is of great importance to design the functional tissue regenerating materials. Synthetic phage, genetically engineered M13 bacteriophage has been recently introduced as novel tissue regeneration materials to display a high density of cell-signaling peptides on their major coat proteins for tissue regeneration purposes. Structural advantages of their long-rod shape and monodispersity can be taken together to construct nanofibrous scaffolds which support cell proliferation and differentiation as well as direct orientation of their growth in two or three dimensions. This review demonstrated how functional synthetic phage is designed and subsequently utilized for tissue regeneration that offers potential cell therapy.

  8. Synthetic biology and its promises

    Directory of Open Access Journals (Sweden)

    José Manuel De Cózar Escalante

    2016-12-01

    Full Text Available Synthetic biology is a new science and emerging technology, or rather a technoscience, which converges with others such as nanotechnology, information technology, robotics, artificial intelligence and neuroscience. All have common features that could have highly concerning social and environmental impacts. With its ambitious goals of controlling complexity, redesigning and creating new living entities, synthetic biology perfectly exemplifies the new bioeconomic reality. This requires expanding the focus of the discussion beyond the limited comparative analysis of risks and benefits, to address uncertainties, reassign responsibilities and initiate a thorough social assessment of what is at stake.

  9. Aircraft route forecasting under adverse weather conditions

    Directory of Open Access Journals (Sweden)

    Thomas Hauf

    2017-04-01

    Full Text Available In this paper storm nowcasts in the terminal manoeuvring area (TMA of Hong Kong International Airport are used to forecast deviation routes through a field of storms for arriving and departing aircraft. Storms were observed and nowcast by the nowcast system SWIRLS from the Hong Kong Observatory. Storms were considered as no-go zones for aircraft and deviation routes were determined with the DIVSIM software package. Two days (21 and 22 May 2011 with 22 actual flown routes were investigated. Flights were simulated with a nowcast issued at the time an aircraft entered the TMA or departed from the airport. These flights were compared with a posteriori simulations, in which all storm fields were known and circumnavigated. Both types of simulated routes were then compared with the actual flown routes. The qualitative comparison of the various routes revealed generally good agreement. Larger differences were found in more complex situations with many active storms in the TMA. Route differences resulted primarily from air traffic control measures imposed such as holdings, slow-downs and shortcuts, causing the largest differences between the estimated and actual landing time. Route differences could be enhanced as aircraft might be forced to circumnavigate a storm ahead in a different sense. The use of route forecasts to assist controllers coordinating flights in a complex moving storm field is discussed. The study emphasises the important application of storm nowcasts in aviation meteorology.

  10. A Machine Learning Concept for DTN Routing

    Science.gov (United States)

    Dudukovich, Rachel; Hylton, Alan; Papachristou, Christos

    2017-01-01

    This paper discusses the concept and architecture of a machine learning based router for delay tolerant space networks. The techniques of reinforcement learning and Bayesian learning are used to supplement the routing decisions of the popular Contact Graph Routing algorithm. An introduction to the concepts of Contact Graph Routing, Q-routing and Naive Bayes classification are given. The development of an architecture for a cross-layer feedback framework for DTN (Delay-Tolerant Networking) protocols is discussed. Finally, initial simulation setup and results are given.

  11. An Asymmetric Synthetic Approach to the A-ring of the Taxol Family of Anti-Cancer Compounds

    Directory of Open Access Journals (Sweden)

    M. L. Marin

    1998-02-01

    Full Text Available A synthetic route developed for the preparation of the A-ring of Taxol family of molecules is reported. By means of an intramolecular Diels-Alder reaction an asymmetric approach to this ring has been accomplished. Also, initial studies to prepare the A ring using an intramolecular Diels-Alder reaction have been successful.

  12. Intelligent emission-sensitive routing for plugin hybrid electric vehicles.

    Science.gov (United States)

    Sun, Zhonghao; Zhou, Xingshe

    2016-01-01

    The existing transportation sector creates heavily environmental impacts and is a prime cause for the current climate change. The need to reduce emissions from this sector has stimulated efforts to speed up the application of electric vehicles (EVs). A subset of EVs, called plug-in hybrid electric vehicles (PHEVs), backup batteries with combustion engine, which makes PHEVs have a comparable driving range to conventional vehicles. However, this hybridization comes at a cost of higher emissions than all-electric vehicles. This paper studies the routing problem for PHEVs to minimize emissions. The existing shortest-path based algorithms cannot be applied to solving this problem, because of the several new challenges: (1) an optimal route may contain circles caused by detour for recharging; (2) emissions of PHEVs not only depend on the driving distance, but also depend on the terrain and the state of charge (SOC) of batteries; (3) batteries can harvest energy by regenerative braking, which makes some road segments have negative energy consumption. To address these challenges, this paper proposes a green navigation algorithm (GNA) which finds the optimal strategies: where to go and where to recharge. GNA discretizes the SOC, then makes the PHEV routing problem to satisfy the principle of optimality. Finally, GNA adopts dynamic programming to solve the problem. We evaluate GNA using synthetic maps generated by the delaunay triangulation. The results show that GNA can save more than 10 % energy and reduce 10 % emissions when compared to the shortest path algorithm. We also observe that PHEVs with the battery capacity of 10-15 KWh detour most and nearly no detour when larger than 30 KWh. This observation gives some insights when developing PHEVs.

  13. US Hazardous Materials Routes, Geographic WGS84, BTS (2006) [hazardous_material_routes_BTS_2006

    Data.gov (United States)

    Louisiana Geographic Information Center — The Federal Motor Carrier Safety Administration (FMCSA) Hazardous Material Routes were developed using the 2004 First Edition TIGER/Line files. The routes are...

  14. Transportation Routing Analysis Geographic Information System -- TRAGIS, progress on improving a routing tool

    International Nuclear Information System (INIS)

    Johnson, P.E.; Lester, P.B.

    1998-05-01

    The Transportation Routing Analysis Geographic Information System (TRAGIS) model provides a useful tool to calculate and analyze transportation routes for radioactive materials within the continental US. This paper outlines some of the features available in this model

  15. Composition and microstructure of zirconium and hafnium germanates obtained by different chemical routes

    International Nuclear Information System (INIS)

    Utkin, A.V.; Prokip, V.E.; Baklanova, N.I.

    2014-01-01

    The phase composition and morphology of zirconium and hafnium germanates synthesized by ceramic and co-precipitation routes were studied. The products were characterized using high-temperature X-ray diffraction analysis (XRD), Raman spectroscopy, scanning electron microscopy (SEM) and thermal (TG/DTA) analysis. To investigate the phase composition and stoichiometry of compounds the unit cell parameters were refined by full-profile Rietveld XRD analysis. The morphology of products and its evolution during high-temperature treatment was examined by SEM analysis. It was stated that there is the strong dependence of the phase composition and morphology of products on the preparation route. The ceramic route requires a multi-stage high-temperature treatment to obtain zirconium and hafnium germanates of 95% purity or more. Also, there are strong diffusion limitations to obtain hafnium germanate Hf 3 GeO 8 by ceramic route. On the contrary, the co-precipitation route leads to the formation of nanocrystalline single phase germanates of stoichiometric composition at a relatively low temperatures (less than 1000 °C). The results of quantitative XRD analysis showed the hafnium germanates are stoichiometric compounds in contrast to zirconium germanates that form a set of solid solutions. This distinction may be related to the difference in the ion radii of Zr and Hf. - Graphical abstract: The phase composition and morphology of zirconium and hafnium germanates synthesized by ceramic and co-precipitation routes were studied. It was stated that there is the strong dependence of the phase composition and morphology of products on the preparation route. Display Omitted - Highlights: • Zr and Hf germanates were synthesized by ceramic and co-precipitation routes. • The morphology of products depends on the synthesis parameters. • Zirconium germanates forms a set of solid solutions. • Hafnium germanates are stoichiometric compounds

  16. Where Synthetic Biology Meets ET

    Science.gov (United States)

    Rothschild, Lynn J.

    2016-01-01

    Synthetic biology - the design and construction of new biological parts and systems and the redesign of existing ones for useful purposes - has the potential to transform fields from pharmaceuticals to fuels. Our lab has focused on the potential of synthetic biology to revolutionize all three major parts of astrobiology: Where do we come from? Where are we going? and Are we alone? For the first and third, synthetic biology is allowing us to answer whether the evolutionary narrative that has played out on planet earth is likely to have been unique or universal. For example, in our lab we are re-evolving the biosynthetic pathways of amino acids in order to understand potential capabilities of an early organism with a limited repertoire of amino acids and developing techniques for the recovery of metals from spent electronics on other planetary bodies. And what about the limits for life? Can we create organisms that expand the envelope for life? In the future synthetic biology will play an increasing role in human activities both on earth, in fields as diverse as human health and the industrial production of novel bio-composites. Beyond earth, we will rely increasingly on biologically-provided life support, as we have throughout our evolutionary history. In order to do this, the field will build on two of the great contributions of astrobiology: studies of the origin of life and life in extreme environments.

  17. Stereoscopy in cinematographic synthetic imagery

    Science.gov (United States)

    Eisenmann, Jonathan; Parent, Rick

    2009-02-01

    In this paper we present experiments and results pertaining to the perception of depth in stereoscopic viewing of synthetic imagery. In computer animation, typical synthetic imagery is highly textured and uses stylized illumination of abstracted material models by abstracted light source models. While there have been numerous studies concerning stereoscopic capabilities, conventions for staging and cinematography in stereoscopic movies have not yet been well-established. Our long-term goal is to measure the effectiveness of various cinematography techniques on the human visual system in a theatrical viewing environment. We would like to identify the elements of stereoscopic cinema that are important in terms of enhancing the viewer's understanding of a scene as well as providing guidelines for the cinematographer relating to storytelling. In these experiments we isolated stereoscopic effects by eliminating as many other visual cues as is reasonable. In particular, we aim to empirically determine what types of movement in synthetic imagery affect the perceptual depth sensing capabilities of our viewers. Using synthetic imagery, we created several viewing scenarios in which the viewer is asked to locate a target object's depth in a simple environment. The scenarios were specifically designed to compare the effectiveness of stereo viewing, camera movement, and object motion in aiding depth perception. Data were collected showing the error between the choice of the user and the actual depth value, and patterns were identified that relate the test variables to the viewer's perceptual depth accuracy in our theatrical viewing environment.

  18. Synthetic biology meets tissue engineering.

    Science.gov (United States)

    Davies, Jamie A; Cachat, Elise

    2016-06-15

    Classical tissue engineering is aimed mainly at producing anatomically and physiologically realistic replacements for normal human tissues. It is done either by encouraging cellular colonization of manufactured matrices or cellular recolonization of decellularized natural extracellular matrices from donor organs, or by allowing cells to self-organize into organs as they do during fetal life. For repair of normal bodies, this will be adequate but there are reasons for making unusual, non-evolved tissues (repair of unusual bodies, interface to electromechanical prostheses, incorporating living cells into life-support machines). Synthetic biology is aimed mainly at engineering cells so that they can perform custom functions: applying synthetic biological approaches to tissue engineering may be one way of engineering custom structures. In this article, we outline the 'embryological cycle' of patterning, differentiation and morphogenesis and review progress that has been made in constructing synthetic biological systems to reproduce these processes in new ways. The state-of-the-art remains a long way from making truly synthetic tissues, but there are now at least foundations for future work. © 2016 Authors; published by Portland Press Limited.

  19. Assessment of synthetic image fidelity

    Science.gov (United States)

    Mitchell, Kevin D.; Moorhead, Ian R.; Gilmore, Marilyn A.; Watson, Graham H.; Thomson, Mitch; Yates, T.; Troscianko, Tomasz; Tolhurst, David J.

    2000-07-01

    Computer generated imagery is increasingly used for a wide variety of purposes ranging from computer games to flight simulators to camouflage and sensor assessment. The fidelity required for this imagery is dependent on the anticipated use - for example when used for camouflage design it must be physically correct spectrally and spatially. The rendering techniques used will also depend upon the waveband being simulated, spatial resolution of the sensor and the required frame rate. Rendering of natural outdoor scenes is particularly demanding, because of the statistical variation in materials and illumination, atmospheric effects and the complex geometric structures of objects such as trees. The accuracy of the simulated imagery has tended to be assessed subjectively in the past. First and second order statistics do not capture many of the essential characteristics of natural scenes. Direct pixel comparison would impose an unachievable demand on the synthetic imagery. For many applications, such as camouflage design, it is important that nay metrics used will work in both visible and infrared wavebands. We are investigating a variety of different methods of comparing real and synthetic imagery and comparing synthetic imagery rendered to different levels of fidelity. These techniques will include neural networks (ICA), higher order statistics and models of human contrast perception. This paper will present an overview of the analyses we have carried out and some initial results along with some preliminary conclusions regarding the fidelity of synthetic imagery.

  20. Methods for preparing synthetic freshwaters.

    Science.gov (United States)

    Smith, E J; Davison, W; Hamilton-Taylor, J

    2002-03-01

    Synthetic solutions that emulate the major ion compositions of natural waters are useful in experiments aimed at understanding biogeochemical processes. Standard recipes exist for preparing synthetic analogues of seawater, with its relatively constant composition, but, due to the diversity of freshwaters, a range of compositions and recipes is required. Generic protocols are developed for preparing synthetic freshwaters of any desired composition. The major problems encountered in preparing hard and soft waters include dissolving sparingly soluble calcium carbonate, ensuring that the ionic components of each concentrated stock solution cannot form an insoluble salt and dealing with the supersaturation of calcium carbonate in many hard waters. For acidic waters the poor solubility of aluminium salts requires attention. These problems are overcome by preparing concentrated stock solutions according to carefully designed reaction paths that were tested using a combination of experiment and equilibrium modeling. These stock solutions must then be added in a prescribed order to prepare a final solution that is brought into equilibrium with the atmosphere. The example calculations for preparing hard, soft and acidic freshwater surrogates with major ion compositions the same as published analyses, are presented in a generalized fashion that should allow preparation of any synthetic freshwater according to its known analysis.

  1. Thermoluminescent characteristics of synthetic hydroxyapatite (SHAp)

    International Nuclear Information System (INIS)

    Alvarez, R.; Rivera, T.; Guzman, J.; Piña-Barba, M.C.; Azorin, J.

    2014-01-01

    This paper presents the experimental results of the thermoluminescent (TL) characteristics of synthetic hydroxyapatite (SHAp) obtained by the sol–gel method. For preparation of the SHAp powders, phosphorus pentoxide (P 2 O 5 ) and calcium nitrate tetrahydrated (Ca(NO 3 ) 2 –4H 2 O) were used. The powders obtained were submitted at different temperatures. The structural and morphological characterization were carried out using X-ray diffraction (XRD) and scanning electron microscopy techniques. TL glow curve exhibited two peaks centered at around 200 °C and 300 °C. TL response of SHAp as a function of gamma absorbed dose was linear over a wide dose range. Fading of the storage information in the samples irradiated was also studied. The experimental results show that the synthetic hydroxyapatite obtained by the sol–gel method may have used in gamma radiation dosimetry applications. - highlights: • Dosimetric characteristics of SHAp under gamma irradiation effect were analyzed • SHAp powders were obtained by Sol–Gel method • Fading anomalous of HAp was performed showing 15% during 90 days • SHAp showed good dosimetric characteristics. • Dosimetric characteristics of SHAp have not been reported yet in the literature before this paper

  2. New Routes to Lanthanide and Actinide Nitrides

    Energy Technology Data Exchange (ETDEWEB)

    Butt, D.P.; Jaques, B.J.; Osterberg, D.D. [Boise State University, 1910 University Dr., Boise, Idaho 83725-2075 (United States); Marx, B.M. [Concurrent Technologies Corporation, Johnstown, PA (United States); Callahan, P.G. [Carnegie Mellon University, Pittsburgh, PA (United States); Hamdy, A.S. [Central Metallurgical R and D Institute, Helwan, Cairo (Egypt)

    2009-06-15

    The future of nuclear energy in the U.S. and its expansion worldwide depends greatly on our ability to reduce the levels of high level waste to minimal levels, while maintaining proliferation resistance. Implicit in the so-called advanced fuel cycle is the need for higher levels of fuel burn-up and consequential use of complex nuclear fuels comprised of fissile materials such as Pu, Am, Np, and Cm. Advanced nitride fuels comprised ternary and quaternary mixtures of uranium and these actinides have been considered for applications in advanced power plants, but there remain many processing challenges as well as necessary qualification testing. In this presentation, the advantages and disadvantages of nitride fuels are discussed. Methods of synthesizing the raw materials and sintering of fuels are described including a discussion of novel, low cost routes to nitrides that have the potential for reducing the cost and footprint of a fuel processing plant. Phase pure nitrides were synthesized via four primary methods; reactive milling metal flakes in nitrogen at room temperature, directly nitriding metal flakes in a pure nitrogen atmosphere, hydriding metal flakes prior to nitridation, and carbo-thermically reducing the metal oxide and carbon mixture prior to nitridation. In the present study, the sintering of UN, DyN, and their solid solutions (U{sub x}, Dy{sub 1-x}) (x = 1 to 0.7) were also studied. (authors)

  3. Route churn: an analysis of low-cost carrier route continuity in Europe

    NARCIS (Netherlands)

    de Wit, J.G.; Zuidberg, J.

    2016-01-01

    Discontinuity of air routes is a subject that has been analysed in various ways. For example, the complex network approach focuses on network robustness and resilience due to route interruptions during a relatively short period. Also seasonal interruptions of air routes are a well-documented

  4. Planning routes around the world: International evidence for southern route preferences

    NARCIS (Netherlands)

    Brunyé, Tad T.; Andonova, Elena; Meneghetti, Chiara; Noordzij, Matthijs Leendert; Pazzaglia, Francesca; Wienemann, Rasmus; Mahoney, Caroline R.; Taylor, Holly A.

    2012-01-01

    Three studies test whether the southern route preference, which describes the tendency for route planners to disproportionately select south- rather than north-going routes, can be attributed to regional elevation patterns; specifically, we ask whether this effect replicates in three topographically

  5. Protease-sensitive synthetic prions.

    Directory of Open Access Journals (Sweden)

    David W Colby

    2010-01-01

    Full Text Available Prions arise when the cellular prion protein (PrP(C undergoes a self-propagating conformational change; the resulting infectious conformer is designated PrP(Sc. Frequently, PrP(Sc is protease-resistant but protease-sensitive (s prions have been isolated in humans and other animals. We report here that protease-sensitive, synthetic prions were generated in vitro during polymerization of recombinant (rec PrP into amyloid fibers. In 22 independent experiments, recPrP amyloid preparations, but not recPrP monomers or oligomers, transmitted disease to transgenic mice (n = 164, denoted Tg9949 mice, that overexpress N-terminally truncated PrP. Tg9949 control mice (n = 174 did not spontaneously generate prions although they were prone to late-onset spontaneous neurological dysfunction. When synthetic prion isolates from infected Tg9949 mice were serially transmitted in the same line of mice, they exhibited sPrP(Sc and caused neurodegeneration. Interestingly, these protease-sensitive prions did not shorten the life span of Tg9949 mice despite causing extensive neurodegeneration. We inoculated three synthetic prion isolates into Tg4053 mice that overexpress full-length PrP; Tg4053 mice are not prone to developing spontaneous neurological dysfunction. The synthetic prion isolates caused disease in 600-750 days in Tg4053 mice, which exhibited sPrP(Sc. These novel synthetic prions demonstrate that conformational changes in wild-type PrP can produce mouse prions composed exclusively of sPrP(Sc.

  6. THE NORTHERN SEA ROUTE: PRESENT CONDITION AND DEVELIPMENT PROSPECTS

    Directory of Open Access Journals (Sweden)

    R. A. Bryzgalov

    2011-01-01

    Full Text Available The Northern Sea Route (NSR represents a serious alternative to traditional so-called «southern» sea transportation routes passing through the Suez Canal. Data on the present and on most optimistic prospective scopes of transportation over NSR for different types of goods are presented in the article. Among main factors working for the optimistic perspective with respect of NSR there are measurements stipulated in several Russian governmental decrees, global rise in temperature and feasibility to develop natural resources abundantly available in the arctic areas of Russia. Still, there are negative factors such as the need of massive investment to transportation means and to local infrastructure, risks associated with the probability of particularly severe arctic natural phenomena and provision for safety in many aspects.

  7. The QKD network: model and routing scheme

    Science.gov (United States)

    Yang, Chao; Zhang, Hongqi; Su, Jinhai

    2017-11-01

    Quantum key distribution (QKD) technology can establish unconditional secure keys between two communicating parties. Although this technology has some inherent constraints, such as the distance and point-to-point mode limits, building a QKD network with multiple point-to-point QKD devices can overcome these constraints. Considering the development level of current technology, the trust relaying QKD network is the first choice to build a practical QKD network. However, the previous research didn't address a routing method on the trust relaying QKD network in detail. This paper focuses on the routing issues, builds a model of the trust relaying QKD network for easily analysing and understanding this network, and proposes a dynamical routing scheme for this network. From the viewpoint of designing a dynamical routing scheme in classical network, the proposed scheme consists of three components: a Hello protocol helping share the network topology information, a routing algorithm to select a set of suitable paths and establish the routing table and a link state update mechanism helping keep the routing table newly. Experiments and evaluation demonstrates the validity and effectiveness of the proposed routing scheme.

  8. Routing in Optical and Stochastic Networks

    NARCIS (Netherlands)

    Yang, S.

    2015-01-01

    In most types of networks (e.g., optical or transportation networks), finding one or more best paths from a source to a destination, is one of the biggest concerns of network users and providers. This process is known as routing. The routing problems differ accordingly depending on different

  9. Classification of Dynamic Vehicle Routing Systems

    DEFF Research Database (Denmark)

    Larsen, Allan; Madsen, Oli B.G.; Solomon, Marius M.

    2007-01-01

    This chapter discusses important characteristics seen within dynamic vehicle routing problems. We discuss the differences between the traditional static vehicle routing problems and its dynamic counterparts. We give an in-depth introduction to the degree of dynamism measure which can be used to c...

  10. Environmental factors along the Northern Sea Route

    International Nuclear Information System (INIS)

    Fjeld, P.E.

    1993-01-01

    The Northern Sea Route runs ca 5,600 nautical miles across the top of Russia from Murmansk to Vladivostok, and includes half of the Arctic basin. An environmental impact assessment is needed for this route because of the potential for commercial shipping to disturb the vulnerable Arctic environment along the route. For example, Russian development of oil and gas resources in the area served by the route is expected to rise dramatically in the near future. Drilling in the route area offshore has already begun, and potential blowouts or tanker spills are of concern. A pilot study on the environment along this route was conducted in 1990/91, focusing on a study of the literature and communications with Russian scientists working on Arctic ecology. Existing data seem to be insufficient and generally only cover the westernmost and easternmost parts of the route. A five-year research plan is proposed to provide an inventory of Arctic species in the route area and levels of contaminants present, to assess the environmental sensitivity of the area, and analyze impacts that increased shipping might have on the environment. Protection measures will also be suggested. 1 fig

  11. Optimizing departure times in vehicle routes

    NARCIS (Netherlands)

    Kok, A.L.; Hans, Elias W.; Schutten, Johannes M.J.

    2008-01-01

    Most solution methods for the vehicle routing problem with time windows (VRPTW) develop routes from the earliest feasible departure time. However, in practice, temporal traffic congestions make that such solutions are not optimal with respect to minimizing the total duty time. Furthermore, VRPTW

  12. Routing in Wireless Multimedia Home Networks

    NARCIS (Netherlands)

    Scholten, Johan; Jansen, P.G.; Hop, Laurens

    This paper describes an adapted version of the destination sequenced distance vector routing protocol (DSDV) which is suitable to calculate routes in a wireless real-time home network. The home network is based on a IEEE 802.11b ad hoc network and uses a scheduled token to enforce real-time

  13. Routing in Wireless Multimedia Home Networks

    NARCIS (Netherlands)

    Scholten, Johan; Jansen, P.G.; Hop, Laurens

    This paper describes an adapted version of the destination sequenced distance vector routing protocol (DSDV) which is suitable to calculate routes in a wireless ¿real-time¿ home network. The home network is based on a IEEE 802.11b ad hoc network and uses a scheduled token to enforce real-time

  14. Perspectives on Illegal Routes in Nigeria

    African Journals Online (AJOL)

    Nneka Umera-Okeke

    University of Kwazulu-Natal. Pietermaritzburg, South ... Key Words: Nigeria Immigration Service, Illegal Routes, Security Policing, Border,. State .... transported weapons across borders to sell them in exchange for food or other commodities. ... The study's respondents were of the opinion that illegal routes exist around the ...

  15. Optimizing Departure Times in Vehicle Routes

    NARCIS (Netherlands)

    Kok, A.L.; Hans, Elias W.; Schutten, Johannes M.J.

    2011-01-01

    Most solution methods for the vehicle routing problem with time windows (VRPTW) develop routes from the earliest feasible departure time. In practice, however, temporary traffic congestion make such solutions non-optimal with respect to minimizing the total duty time. Furthermore, the VRPTW does not

  16. Energy Efficient Routing in Nomadic Networks

    DEFF Research Database (Denmark)

    Kristensen, Mads Darø; Bouvin, Niels Olof

    2007-01-01

    We present an evaluation of a novel energy-efficient routing protocol for mobile ad-hoc networks. We combine two techniques for optimizing energy levels with a well-known routing protocol. We examine the behavior of this combination in a nomadic network setting, where some nodes are stationary...

  17. Joint route planning under varying market conditions

    NARCIS (Netherlands)

    Cruijssen, Frans; Bräysy, Olli; Dullaert, Wout; Fleuren, Hein; Salomon, Marc

    2007-01-01

    Purpose - To provide empirical evidence on the level of savings that can be attained by joint route planning and how these savings depend on specific market characteristics. Design/methodology/approach - Joint route planning is a measure that companies can take to decrease the costs of their

  18. Time and timing in vehicle routing problems

    NARCIS (Netherlands)

    Jabali, O.

    2010-01-01

    The distribution of goods to a set of geographically dispersed customers is a common problem faced by carrier companies, well-known as the Vehicle Routing Problem (VRP). The VRP consists of finding an optimal set of routes that minimizes total travel times for a given number of vehicles with a fixed

  19. Production of BaAl{sub 2}O{sub 4} doped with Eu{sup 3+} in low temperature: research of the influence of the synthesis route, temperature and calcination time in the optical properties; Producao do BaAl{sub 2}O{sub 4} dopado com Eu{sup 3+} em baixa temperatura: investigacao da influencia da rota de sintese, temperatura e tempo de calcinacao nas propriedades opticas

    Energy Technology Data Exchange (ETDEWEB)

    Gomes, Manasses Almeida

    2017-07-01

    In this work, the synthesis condition (complexing agent and temperature and time of calcination) were studied aiming to produce BaAl{sub 2}O{sub 4} samples in the ferroelectric hexagonal phase. Pure and Eu{sup 3+} - doped samples were produced and its luminescent properties were investigated. BaAl{sub 2}O{sub 4} was prepared using several thermal treatment conditions, via an alternative sol-gel route, using coconut water or PVA as the complexing agents. The sample production at 600 °C/5h is quite interesting, since to date the lowest calcination temperatures found in the literature was 650 ° C using reagents with high degree of toxicity DTA / TG measurements indicated a possible start of the crystallization of the material at approximately 600 ° C, and the X-ray powder diffraction (XRD) confirm the formation of the desired phase of the calcined barium aluminate at that temperature. The results of the Rietveld refinements showed the occurrence of secondary phase in the samples produced at 600 ° C / 5h, presenting 5% of phase Ba(NO{sub 3}){sub 2}, while single phase was found for samples calcined at 1200 ° C for 2 and 5h. Analysis of the diffractogram by the Scherrer equation showed smaller crystallite size for samples calcified at 600 °C/5h, but apparently with a lower degree of crystallinity than the sample prepared at 1200 ° C/ 2 and 5h. The photoluminescence measurements showed that the emission spectra of the samples have great dependence on the times, temperatures and complexing agents used. In particular, samples calcined at 600 ° C have very different characteristics with regard to the probabilities of emissions associated with Eu{sup 3+} when compared with samples produced at higher temperatures. Differences observed in the spectra of samples produced via different complexing agents are possibly due to defects created in the materials by impurities present in the coconut water. Samples produced using PVA present sites with higher symmetry, which was

  20. Routing architecture and security for airborne networks

    Science.gov (United States)

    Deng, Hongmei; Xie, Peng; Li, Jason; Xu, Roger; Levy, Renato

    2009-05-01

    Airborne networks are envisioned to provide interconnectivity for terrestial and space networks by interconnecting highly mobile airborne platforms. A number of military applications are expected to be used by the operator, and all these applications require proper routing security support to establish correct route between communicating platforms in a timely manner. As airborne networks somewhat different from traditional wired and wireless networks (e.g., Internet, LAN, WLAN, MANET, etc), security aspects valid in these networks are not fully applicable to airborne networks. Designing an efficient security scheme to protect airborne networks is confronted with new requirements. In this paper, we first identify a candidate routing architecture, which works as an underlying structure for our proposed security scheme. And then we investigate the vulnerabilities and attack models against routing protocols in airborne networks. Based on these studies, we propose an integrated security solution to address routing security issues in airborne networks.

  1. Entanglement-Gradient Routing for Quantum Networks.

    Science.gov (United States)

    Gyongyosi, Laszlo; Imre, Sandor

    2017-10-27

    We define the entanglement-gradient routing scheme for quantum repeater networks. The routing framework fuses the fundamentals of swarm intelligence and quantum Shannon theory. Swarm intelligence provides nature-inspired solutions for problem solving. Motivated by models of social insect behavior, the routing is performed using parallel threads to determine the shortest path via the entanglement gradient coefficient, which describes the feasibility of the entangled links and paths of the network. The routing metrics are derived from the characteristics of entanglement transmission and relevant measures of entanglement distribution in quantum networks. The method allows a moderate complexity decentralized routing in quantum repeater networks. The results can be applied in experimental quantum networking, future quantum Internet, and long-distance quantum communications.

  2. User habits and multimodal route planning

    Directory of Open Access Journals (Sweden)

    Géza Katona

    2017-10-01

    Full Text Available The results of route planning researches are monitored by logistic and automotive industries. The economic aspects of the cost saving are in the focus of the attention. An optimal route could cause time or fuel savings. An effective driving or an optimal route is a good basis to achieve an economical aim. Moreover the spread of new automotive solutions especially in case of electric cars the optimisation has particular significance regarding the limited battery storage. Additionally the autonomous car development could not be neglected. As a result the society could expect safer roads, better space usage and effective resource management. Nevertheless the requirements of users are extremely diverse, which is not negligible. Supporting these aims, in this paper the connection between the multimodal route planning and the user requirements are investigated. The examination is focused to a sensitivity analysis and a survey to evaluate the data and support the settings of a user habit effect to the final route.

  3. Highway and interline transportation routing models

    International Nuclear Information System (INIS)

    Joy, D.S.; Johnson, P.E.

    1994-01-01

    The potential impacts associated with the transportation of hazardous materials are important issues to shippers, carriers, and the general public. Since transportation routes are a central characteristic in most of these issues, the prediction of likely routes is the first step toward the resolution of these issues. In addition, US Department of Transportation requirements (HM-164) mandate specific routes for shipments of highway controlled quantities of radioactive materials. In response to these needs, two routing models have been developed at Oak Ridge National Laboratory under the sponsorship of the U.S. Department of Energy (DOE). These models have been designated by DOE's Office of Environmental Restoration and Waste Management, Transportation Management Division (DOE/EM) as the official DOE routing models. Both models, HIGHWAY and INTERLINE, are described

  4. Synthetic Stromgren photometry for F dwarf stars

    Science.gov (United States)

    Bell, R. A.

    1988-01-01

    Recent synthetic spectrum and color calculations for cool dwarf star models are tested by comparison with observation. The accuracy of the computed dependence of the thermal colors B-V and b-y on effective temperature is examined, and H-beta indices are presented and compared with observed values. The accuracy of the predictions of the Stromgren uvby system metal-abundance indicator m1 and luminosity indicator c1 are tested. A new calibration of the c1, b-y diagram in terms of absolute magnitudes is given, making use of recent calculations of stellar isochrones. Observations of very metal-poor subdwarfs are used to study the accuracy of the isochrones. The c1, b-y diagram of the subdwarfs is compared with that of the turnoff-region stars in the very metal-poor globular cluster NGC 6397.

  5. Critical Routes: Women Facing Violence

    Directory of Open Access Journals (Sweden)

    Stela Nazareth Meneghel

    2008-11-01

    Full Text Available This paper presents the Critical Routes International Seminar – Women Facing Violence , which took place in Porto Alegre in 2008. The seminar was promoted by the Graduate Program on Collective Health at Unisinos and by the Public Health School/RS and was supported by outstanding researchers working in the fields of collective health, and social and human sciences. Initially, we discuss some conceptual aspects about gender violence, its dimensions and its consequences for the health and the life quality of the affected women. Our understanding is that violence is one of the most effective methods of controlling women in societies scarred with gender hierarchies. The structure of the seminar focused on three main discussion themes: breaking up with the violence, mechanisms for working with gender and hearing the services. These themes were chosen aiming at looking for ways to help the women and to explore efficient mechanisms to combat, reduce and, if possible, eliminate the violence perpetrated against women. At the end of the seminar, we reiterate the political commitment on the accomplishment of the public policies to face violence and the fight against all inequality, discrimination and violence forms based on gender.

  6. Route analysis for MHD equilibria

    International Nuclear Information System (INIS)

    Kikuchi, Fumio; Aizawa, Tatsuhiko

    1982-01-01

    In Tokamak facilities which are promising in nuclear fusion reactor development, the plasma in the core is often described by MHD approximation. Specifically, since an axisymmetric torus is approximately assumed as the first wall (shell) shape in actual Tokamak facilities, the Grad-Shafranov equation to be satisfied by an axisymmetric equilibrium solution for ideal MHD fluid must be solved, and the characteristics of its solution must be clarified. This paper shows the outline of the numerical calculation which employs both the incremental method taking the particular incremental nodal point values as the control parameters and the interaction method in accordance with Newton method at the same time, the analysis objective being a non-linear eigenvalue problem dealing the boundary of plasma region with surrounding vacuum region as the free boundary. Next, the detailed route analysis of the equilibrium solution is performed, utilizing the above numerical calculation technique, to clarify the effect of shell shape on the behaviour of the equilibrium solution. As the shape of the shell, a rectangular section torus, which have a notch depression at a part of the shell inner boundary, is considered. In the paper, the fundamental MHD equation and its approximate solution by the finite element method, the behaviour of plasma equilibrium solution in a shell having a notch, and the effect of notch shapes on plasma behaviour are described. This analysis verifies the effectiveness of the calculation method. (Wakatsuki, Y.)

  7. Surfactant-directed synthesis of mesoporous films made single-step by a tandem photosol-gel/photocalcination route

    Energy Technology Data Exchange (ETDEWEB)

    De Paz-Simon, Héloïse; Chemtob, Abraham, E-mail: abraham.chemtob@uha.fr; Croutxé-Barghorn, Céline [Laboratory of Macromolecular Photochemistry and Engineering, ENSCMu, University of Haute-Alsace, 3 bis rue Alfred Werner, 68093 Mulhouse Cedex (France); Rigolet, Séverinne; Michelin, Laure; Vidal, Loïc; Lebeau, Bénédicte [Institut de Science des Matériaux de Mulhouse, UMR-CNRS 7361, University of Haute-Alsace, 3 rue Alfred Werner, 68093 Mulhouse Cedex (France)

    2014-11-01

    In view of their technological impact in materials chemistry, a simplified and more efficient synthetic route to mesoporous films is highly sought. We report, herein, a smart UV-mediated approach coupling in a one-stage process sol-gel photopolymerization and photoinduced template decomposition/ablation to making mesoporous silica films. Performed at room temperature with a solvent-free solution of silicate precursor and amphiphilic poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) block copolymer, the synthesis relies on photoacid generation to induce the fast formation (≈10 min) of mesostructured silica/surfactant domains. Continuation of UV exposure for three additional hours enables subsequent and complete photodegradation of the polyether copolymer, resulting in ordered or disordered mesoporous silica film. One of the most attractive features is that the one-step procedure relies on a continuous illumination provided by the same conventional medium-pressure Hg-Xe arc lamp equipped with a 254 nm reflector to enhance the emission of energetic photons <300 nm. In addition to X-ray diffraction and transmission electron microscopy, time-resolved Fourier transform infrared spectroscopy has proved to be a powerful in situ technique to probe the different chemical transformations accompanying irradiation. Photocalcination strengthens the inorganic network, while allowing to preserve a higher fraction of residual silanol groups compared with thermal calcination. A polyether chain degradation mechanism based on oxygen reactive species-mediated photo-oxidation is proposed.

  8. Vaping Synthetic Cannabinoids: A Novel Preclinical Model of E-Cigarette Use in Mice

    Directory of Open Access Journals (Sweden)

    Timothy W Lefever

    2017-03-01

    Full Text Available Smoking is the most common route of administration for cannabis; however, vaping cannabis extracts and synthetic cannabinoids (“fake marijuana” in electronic cigarette devices has become increasingly popular. Yet, most animal models used to investigate biological mechanisms underlying cannabis use employ injection as the route of administration. This study evaluated a novel e-cigarette device that delivers aerosolized cannabinoids to mice. The effects of aerosolized and injected synthetic cannabinoids (CP 55,940, AB-CHMINACA, XLR-11, and JWH-018 in mice were compared in a battery of bioassays in which psychoactive cannabinoids produce characteristic effects. The most potent cannabinoids (CP 55,940 and AB-CHMINACA produced the full cannabinoid profile (ie, hypothermia, hypolocomotion, and analgesia, regardless of the route of administration. In contrast, aerosolized JWH-018 and XLR-11 did not produce the full profile of cannabimimetic effects. Results of time course analysis for hypothermia showed that aerosol exposure to CP 55,940 and AB-CHMINACA produced faster onset of effects and shorter duration of action than injection. The ability to administer cannabinoids to rodents using the most common route of administration among humans provides a method for collecting preclinical data with enhanced translational relevance.

  9. Vaping Synthetic Cannabinoids: A Novel Preclinical Model of E-Cigarette Use in Mice.

    Science.gov (United States)

    Lefever, Timothy W; Marusich, Julie A; Thomas, Brian F; Barrus, Daniel G; Peiper, Nicholas C; Kevin, Richard C; Wiley, Jenny L

    2017-01-01

    Smoking is the most common route of administration for cannabis; however, vaping cannabis extracts and synthetic cannabinoids ("fake marijuana") in electronic cigarette devices has become increasingly popular. Yet, most animal models used to investigate biological mechanisms underlying cannabis use employ injection as the route of administration. This study evaluated a novel e-cigarette device that delivers aerosolized cannabinoids to mice. The effects of aerosolized and injected synthetic cannabinoids (CP 55,940, AB-CHMINACA, XLR-11, and JWH-018) in mice were compared in a battery of bioassays in which psychoactive cannabinoids produce characteristic effects. The most potent cannabinoids (CP 55,940 and AB-CHMINACA) produced the full cannabinoid profile (ie, hypothermia, hypolocomotion, and analgesia), regardless of the route of administration. In contrast, aerosolized JWH-018 and XLR-11 did not produce the full profile of cannabimimetic effects. Results of time course analysis for hypothermia showed that aerosol exposure to CP 55,940 and AB-CHMINACA produced faster onset of effects and shorter duration of action than injection. The ability to administer cannabinoids to rodents using the most common route of administration among humans provides a method for collecting preclinical data with enhanced translational relevance.

  10. Polyethylenimine-mediated synthetic insertion of gold nanoparticles into mesoporous silica nanoparticles for drug loading and biocatalysis.

    Science.gov (United States)

    Pandey, Prem C; Pandey, Govind; Narayan, Roger J

    2017-03-27

    Mesoporous silica nanoparticles (MSNPs) have been used as an efficient and safe carrier for drug delivery and biocatalysis. The surface modification of MSNPs using suitable reagents may provide a robust framework in which two or more components can be incorporated to give multifunctional capabilities (e.g., synthesis of noble metal nanoparticles within mesoporous architecture along with loading of a bioactive molecule). In this study, the authors reported on a new synthetic route for the synthesis of gold nanoparticles (AuNPs) within (1) unmodified MSNPs and (2) 3-trihydroxysilylpropyl methylphosphonate-modified MSNPs. A cationic polymer, polyethylenimine (PEI), and formaldehyde were used to mediate synthetic incorporation of AuNPs within MSNPs. The AuNPs incorporated within the mesoporous matrix were characterized by transmission electron microscopy, energy dispersive x-ray analysis, and high-resolution scanning electron microscopy. PEI in the presence of formaldehyde enabled synthetic incorporation of AuNPs in both unmodified and modified MSNPs. The use of unmodified MSNPs was associated with an increase in the polycrystalline structure of the AuNPs within the MSNPs. The AuNPs within modified MSNPs showed better catalytic activity than those within unmodified MSNPs. MSNPs with an average size of 200 nm and with a pore size of 4-6 nm were used for synthetic insertion of AuNPs. It was found that the PEI coating enabled AuNPs synthesis within the mesopores in the presence of formaldehyde or tetrahydrofuran hydroperoxide at a temperature between 10 and 25 °C or at 60 °C in the absence of organic reducing agents. The as-made AuNP-inserted MSNPs exhibited enhanced catalytic activity. For example, these materials enabled rapid catalytic oxidation of the o-dianisidine substrate to produce a colored solution in proportion to the amount of H 2 O 2 generated as a function of glucose oxidase-catalyzed oxidation of glucose; a linear concentration range from 80 to

  11. Catalysts for synthetic liquid fuels

    Energy Technology Data Exchange (ETDEWEB)

    Bruce, L.A.; Turney, T.W.

    1987-12-01

    Fischer-Tropsch catalysts have been designed, characterized and tested for the selective production of hydrocarbons suitable as synthetic liquid transport fuels from synthesis gas (i.e., by the reduction of carbon monoxide with hydrogen). It was found that hydrocarbons in the middle distillate range, or suitable for conversion to that range, could be produced over several of the new catalyst systems. The various catalysts examined included: (1) synthetic cobalt clays, mainly cobalt chlorites; (2) cobalt hydrotalcites; (3) ruthenium metal supported on rare earth oxides of high surface area; and (4) a novel promoted cobalt catalyst. Active and selective catalysts have been obtained, in each category. With the exception of the clays, reproducibility of catalyst performance has been good. Catalysts in groups 2 and 4 have exhibited very high activity, with long lifetimes and easy regeneration.

  12. Design Automation in Synthetic Biology.

    Science.gov (United States)

    Appleton, Evan; Madsen, Curtis; Roehner, Nicholas; Densmore, Douglas

    2017-04-03

    Design automation refers to a category of software tools for designing systems that work together in a workflow for designing, building, testing, and analyzing systems with a target behavior. In synthetic biology, these tools are called bio-design automation (BDA) tools. In this review, we discuss the BDA tools areas-specify, design, build, test, and learn-and introduce the existing software tools designed to solve problems in these areas. We then detail the functionality of some of these tools and show how they can be used together to create the desired behavior of two types of modern synthetic genetic regulatory networks. Copyright © 2017 Cold Spring Harbor Laboratory Press; all rights reserved.

  13. Synthetic biology character and impact

    CERN Document Server

    Pade, Christian; Wigger, Henning; Gleich, Arnim

    2015-01-01

    Synthetic Biology is already an object of intensive debate. However, to a great extent the discussion to date has been concerned with fundamental ethical, religious and philosophical questions. By contrast, based on an investigation of the field’s scientific and technological character, this book focuses on new functionalities provided by synthetic biology and explores the associated opportunities and risks. Following an introduction to the subject and a discussion of the most central paradigms and methodologies, the book provides an overview of the structure of this field of science and technology. It informs the reader about the current stage of development, as well as topical problems and potential opportunities in important fields of application. But not only the science itself is in focus. In order to investigate its broader impact, ecological as well as ethical implications will be considered, paving the way for a discussion of responsibilities in the context of a field at a transitional crossroads be...

  14. Synthetic greenhouse gases under control

    International Nuclear Information System (INIS)

    Horisberger, B.; Karlaganis, G.

    2003-01-01

    This article discusses new Swiss regulations on the use of synthetic materials that posses a considerable greenhouse-warming potential. Synthetic materials such as hydro-chlorofluorocarbons HCFCs, perfluoride-hydrocarbons and sulphur hexafluoride have, in recent years, replaced chlorofluorocarbons CFCs, which were banned on account of their ozone depletion characteristics. The use of these persistent substances is now being limited to applications where more environment-friendly alternatives are not available. The measures decreed in the legislation, which include a general ban on HCFCs as of 2004 and a ban on the export of installations and equipment that use ozone-depleting refrigerants are described. Details on the legislation's effects on the Swiss refrigeration industry are listed and discussed

  15. Synthetic LDL as targeted drug delivery vehicle

    Science.gov (United States)

    Forte, Trudy M [Berkeley, CA; Nikanjam, Mina [Richmond, CA

    2012-08-28

    The present invention provides a synthetic LDL nanoparticle comprising a lipid moiety and a synthetic chimeric peptide so as to be capable of binding the LDL receptor. The synthetic LDL nanoparticle of the present invention is capable of incorporating and targeting therapeutics to cells expressing the LDL receptor for diseases associated with the expression of the LDL receptor such as central nervous system diseases. The invention further provides methods of using such synthetic LDL nanoparticles.

  16. Vibrational spectrum of synthetic carnotite

    Energy Technology Data Exchange (ETDEWEB)

    Baran, E J; Botto, I L [La Plata Univ. Nacional (Argentina). Facultad de Ciencias Exactas

    1976-05-01

    The infrared and laser-Raman spectra of synthetic carnotite, K/sub 2/((UO/sub 2/)/sub 2/V/sub 2/O/sub 8/), are reported and discussed. Force constants for the terminal V-O bonds as well as for the UO/sub 2//sup 2 +/ ions are evaluated. From the spectroscopic data, a U-O bond length of 1.81 A is estimated for the uranyl ion in this compound.

  17. Designer Drugs: A Synthetic Catastrophe

    OpenAIRE

    Fratantonio, James; Andrade, Lawrence; Febo, Marcelo

    2015-01-01

    Synthetic stimulants can cause hallucinations, aggressive behaviors, death and are sometimes legal. These substances are sold as plant food and bath salts that are "Not for Human Consumption", therefore skirting the 1986 Federal Analogue Act and giving a false pretense of safety. Studies have proved that these substances are toxic, have a high abuse potential, and are becoming extremely prevalent in the United States. This creates a dilemma for law enforcement agents, hospitals, and substance...

  18. Porcelain tiles by the dry route

    International Nuclear Information System (INIS)

    Melchiades, F. G.; Daros, M. T.; Boschi, A. O.

    2010-01-01

    In Brazil, the second largest tile producer of the world, at present, 70% of the tiles are produced by the dry route. One of the main reasons that lead to this development is the fact that the dry route uses approximately 30% less thermal energy them the traditional wet route. The increasing world concern with the environment and the recognition of the central role played by the water also has pointed towards privileging dry processes. In this context the objective of the present work is to study the feasibility of producing high quality porcelain tiles by the dry route. A brief comparison of the dry and wet route, in standard conditions industrially used today to produce tiles that are not porcelain tiles, shows that there are two major differences: the particle sizes obtained by the wet route are usually considerably finer and the capability of mixing the different minerals, the intimacy of the mixture, is also usually better in the wet route. The present work studied the relative importance of these differences and looked for raw materials and operational conditions that would result in better performance and glazed porcelain tiles of good quality. (Author) 7 refs.

  19. Stability of Synthetic Cathinones in Urine.

    Science.gov (United States)

    Glicksberg, Lindsay; Kerrigan, Sarah

    2018-03-01

    In this report, we evaluate the concentration, pH, temperature and analyte-dependent effects on cathinone stability in preserved human urine. A total of 22 synthetic cathinones were evaluated at 100 ng/mL and 1,000 ng/mL in pH 4 and pH 8 urine over 6 months. Specimens were stored at -20°C, 4°C, 20°C and 32°C. The stability of synthetic cathinones was highly dependent on urine pH and storage temperature. Cathinones were considerably more stable in acidic urine (pH 4) at low temperature. In alkaline urine (pH 8) at 32°C, significant losses (>20%) were observed within hours for the majority of drugs. In contrast, all drugs were stable in frozen and refrigerated urine at pH 4 for the duration of the study. These results highlight the importance of sample storage and the potential for pre-analytical changes in concentration during routine shipping and handling of specimens. Significant structural influence was also observed. Cathinones bearing a tertiary amine (pyrrolidine group) were significantly more stable than their secondary amine counterparts. The methylenedioxy group also exerted a significant stabilizing effect on both the tertiary and secondary amines. In the absence of the methylenedioxy group, no significant differences in stability were observed between the unsubstituted and ring substituted secondary amines. Half-lives at ambient temperature in pH 8 urine ranged from 9 h (3-fluoromethcathinone) to 4.3 months (methylenedioxypyrovalerone and 3,4-methylenedioxy-α-pyrrolidinobutiophenone), demonstrating the importance of analyte dependence, and the dual stabilizing effect of both the pyrollidine and methylenedioxy groups. Biological evidence may be subjected to a variety of environmental conditions prior to, and during transport to the forensic laboratory. These findings demonstrate the inherent instability of certain cathinone species in biological evidence under some conditions. Moreover, this study highlights the need for quantitative drug findings in

  20. The path to next generation biofuels: successes and challenges in the era of synthetic biology

    Science.gov (United States)

    2010-01-01

    Volatility of oil prices along with major concerns about climate change, oil supply security and depleting reserves have sparked renewed interest in the production of fuels from renewable resources. Recent advances in synthetic biology provide new tools for metabolic engineers to direct their strategies and construct optimal biocatalysts for the sustainable production of biofuels. Metabolic engineering and synthetic biology efforts entailing the engineering of native and de novo pathways for conversion of biomass constituents to short-chain alcohols and advanced biofuels are herewith reviewed. In the foreseeable future, formal integration of functional genomics and systems biology with synthetic biology and metabolic engineering will undoubtedly support the discovery, characterization, and engineering of new metabolic routes and more efficient microbial systems for the production of biofuels. PMID:20089184

  1. Synthetic approaches to aromatic belts: building up strain in macrocyclic polyarenes.

    Science.gov (United States)

    Eisenberg, David; Shenhar, Roy; Rabinovitz, Mordecai

    2010-08-01

    This tutorial review discusses synthetic strategies towards aromatic belts, defined here as double-stranded conjugated macrocycles, such as [n]cyclacenes, [n]cyclophenacenes, Schlüter belt, and Vögtle belt. Their appeal stems, firstly, from the unique nature of their conjugation, having p orbitals oriented radially rather than perpendicular to the plane of the macrocycle. Secondly, as aromatic belts are model compounds of carbon nanotubes of different chiralities, a synthetic strategy towards the buildup of structural strain in these compounds could finally open a route towards rational chemical synthesis of carbon nanotubes. The elusiveness of these compounds has stimulated fascinating and ingenious synthetic strategies over the last decades. The various strategies are classified here by their approach to the buildup of structural strain, which is the main obstacle in the preparation of these curved polyarenes.

  2. Hydrogen speciation in synthetic quartz

    Science.gov (United States)

    Aines, R.D.; Kirby, S.H.; Rossman, G.R.

    1984-01-01

    The dominant hydrogen impurity in synthetic quartz is molecular H2O. H-OH groups also occur, but there is no direct evidence for the hydrolysis of Si-O-Si bonds to yield Si-OH HO-Si groups. Molecular H2O concentrations in the synthetic quartz crystals studied range from less than 10 to 3,300 ppm (H/Si), and decrease smoothly by up to an order of magnitude with distance away from the seed. OH- concentrations range from 96 to 715 ppm, and rise smoothly with distance away from the seed by up to a factor of three. The observed OH- is probably all associated with cationic impurities, as in natural quartz. Molecular H2O is the dominant initial hydrogen impurity in weak quartz. The hydrolytic weakening of quartz may be caused by the transformation H2O + Si-O-Si ??? 2SiOH, but this may be a transitory change with the SiOH groups recombining to form H2O, and the average SiOH concentration remaining very low. Synthetic quartz is strengthened when the H2O is accumulated into fluid inclusions and cannot react with the quartz framework. ?? 1984 Springer-Verlag.

  3. Characterization of synthetic peptides by mass spectrometry

    DEFF Research Database (Denmark)

    Prabhala, Bala Krishna; Mirza, Osman Asghar; Højrup, Peter

    2015-01-01

    Mass spectrometry (MS) is well suited for analysis of the identity and purity of synthetic peptides. The sequence of a synthetic peptide is most often known, so the analysis is mainly used to confirm the identity and purity of the peptide. Here, simple procedures are described for MALDI......-TOF-MS and LC-MS of synthetic peptides....

  4. A Performance Study of LEACH and Direct Diffusion Routing Protocols in Wireless Sensor Network

    International Nuclear Information System (INIS)

    Fakher, S.; Sharshar, K.; Moawad, M.I.; Shokair, M.

    2016-01-01

    The Wireless Sensor Network (WSN) is composed of a large number of sensor nodes with limited computation communication, and battery facilities. One of the common applications of this network is environment monitoring through sensing motion, measuring temperature, humidity and radiation. One of the basic activities in WSN is data gathering which represents a great challenge. Many routing protocols are proposed for that network to collect and aggregate the data. The most popular ones are hierarchy and data centric routing protocols. The main goal of this study is to identify the most preferable routing protocol, to be used in each mobility model. This paper studies the performance of LEACH (Low Energy Adaptive Clustering Hierarchy) from hierarchy routing protocol and direct diffusion from data centric routing protocol which is not clarified until now. Moreover, a comparison between LEACH and direct diffusion protocol using NS2 simulator will be made, and an analysis of these protocols will be conducted. The comparison includes packet delivery ratio, throughput, average energy ratio, average delay, network lifetime, and routing overhead. The performance is evaluated by varying the number of sensor nodes under three mobility models Reference Point Group Mobility Model (RPGM), Manhattan and random waypoint mobility model. Simulation results show that LEACH routing protocol has a good performance in RPGM and Manhattan than random waypoint mobility model. Direct diffusion has a good performance in random waypoint mobility model than in RPGM and Manhattan mobility model

  5. On line routing per mobile phone

    DEFF Research Database (Denmark)

    Bieding, Thomas; Görtz, Simon; Klose, Andreas

    2009-01-01

    On-line routing is concerned with building vehicle routes in an ongoing fashion in such a way that customer requests arriving dynamically in time are efficiently and effectively served. An indispensable prerequisite for applying on-line routing methods is mobile communication technology....... Additionally it is of utmost importance that the employed communication system is suitable integrated with the firm’s enterprise application system and business processes. On basis of a case study, we describe in this paper a system that is cheap and easy to implement due to the use of simple mobile phones...

  6. Wake-based ship route estimation in high-resolution SAR images

    Science.gov (United States)

    Graziano, M. Daniela; Rufino, Giancarlo; D'Errico, Marco

    2014-10-01

    This paper presents a novel algorithm for wake detection in Synthetic Aperture Radar images of the sea. The algorithm has been conceived as part of a ship traffic monitoring system, in charge of ship detection validation and to estimate ship route features, such as heading and ground speed. In addition, it has been intended to be adequate for inclusion in an automatic procedure without human operator supervision. The algorithm exploits the Radon transform to identify the images ship wake on the basis of the well known theoretical characteristics of the wakes' geometry and components, that are the turbulent wake, the narrow-V wakes, and the Kelvin arms, as well as the typical appearance of such components in Synthetic Aperture Radar images of the sea as bright or dark linear feature. Examples of application to high-resolution X-band Synthetic Aperture Radar products (COSMOSkymed and TerraSAR-X) are reported, both for wake detection and ship route estimation, showing the achieved quality and reliability of wake detection, adequacy to automatic procedures, as well as speed measure accuracy.

  7. Cost analysis of hybrid adaptive routing protocol for heterogeneous ...

    Indian Academy of Sciences (India)

    NONITA SHARMA

    Event detection; wireless sensor networks; hybrid routing; cost benefit analysis; proactive routing; reactive routing. 1. ... additional energy, high processing power, etc. are deployed to extend the .... transmit to its parent node. (2) Reactive ...

  8. Synthesis and study of the synthetic hydroxyapatite doped with aluminum

    Science.gov (United States)

    Goldberg, M.; Smirnov, V.; Antonova, O.; Konovalov, A.; Fomina, A.; Komlev, V. S.; Barinov, S.; Rodionov, A.; Gafurov, M.; Orlinskii, S.

    2018-05-01

    Powders of synthetic hydroxyapatite doped with aluminium (Al) ions in concentrations 0 and 20 mol. % were synthesized by the precipitation method from the nitrate solutions and investigated by atomic emission spectrometry with inductively coupled plasma (AES-ICP), X-ray diffraction (XRD), scanning electron microscopy (SEM), gas absorption and conventional electron paramagnetic resonance (EPR). It is shown that for the chosen synthesis route an introduction of Al provokes formation of highly anisotropic phase, leads to the decrease in the crystallinity while no significant changes in the EPR spectra of the radiation-induced defects is observed. The results could be used for understanding the structural transformations with Al doping of the mineralized materials for geological and biomedical applications.

  9. An Overview of the Glass Transition Temperature of Synthetic Polymers.

    Science.gov (United States)

    Beck, Keith R.; And Others

    1984-01-01

    Presents an overview of the glass-to-rubber transition, what it is, why it is important, and the major factors that influence it. Indicates that this information should be incorporated into chemistry curricula. (JN)

  10. A new route to copper nitrate hydroxide microcrystals

    International Nuclear Information System (INIS)

    Niu Haixia; Yang Qing; Tang Kaibin

    2006-01-01

    A solution evaporation route has been successfully developed for the growth of copper nitrate hydroxide microcrystals using copper nitrate solution as the starting material in the absence of any surfactants or templates. The products were characterized by X-ray diffraction (XRD), infrared (IR) spectrum, scanning electron microscopy (SEM) and thermogravimetric (TG) analysis measurements. Controlled experiments suggested that the reaction temperature and solution concentration played an important role on the formation of the products. A possible formation mechanism of the products was also proposed

  11. Dams and Obstructions along Iowa's Canoe Routes

    Data.gov (United States)

    Iowa State University GIS Support and Research Facility — This dataset represents obstruction to canoe and boat users of the canoe routes of Iowa. This may represent actual dams, rock dams (natural or man made), large...

  12. Integrating routing decisions in public transportation problems

    CERN Document Server

    Schmidt, Marie E

    2014-01-01

    This book treats three planning problems arising in public railway transportation planning: line planning, timetabling, and delay management, with the objective to minimize passengers’ travel time. While many optimization approaches simplify these problems by assuming that passengers’ route choice is independent of the solution, this book focuses on models which take into account that passengers will adapt their travel route to the implemented planning solution. That is, a planning solution and passengers’ routes are determined and evaluated simultaneously. This work is technically deep, with insightful findings regarding complexity and algorithmic approaches to public transportation problems with integrated passenger routing. It is intended for researchers in the fields of mathematics, computer science, or operations research, working in the field of public transportation from an optimization standpoint. It is also ideal for students who want to gain intuition and experience in doing complexity proofs ...

  13. Commercial vehicle route tracking using video detection.

    Science.gov (United States)

    2010-10-31

    Interstate commercial vehicle traffic is a major factor in the life of any road surface. The ability to track : these vehicles and their routes through the state can provide valuable information to planning : activities. We propose a method using vid...

  14. Locating Depots for Capacitated Vehicle Routing

    DEFF Research Database (Denmark)

    Gørtz, Inge Li; Nagarajan, Viswanath

    2016-01-01

    We study a location-routing problem in the context of capacitated vehicle routing. The input to the k-location capacitated vehicle routing problem (k-LocVRP) consists of a set of demand locations in a metric space and a fleet of k identical vehicles, each of capacity Q. The objective is to locate k...... depots, one for each vehicle, and compute routes for the vehicles so that all demands are satisfied and the total cost is minimized. Our main result is a constant-factor approximation algorithm for k-LocVRP. In obtaining this result, we introduce a common generalization of the k-median and minimum...... spanning tree problems (called k median forest), which might be of independent interest. We give a local-search based (3+ε)-approximation algorithm for k median forest, which leads to a (12+ε)-approximation algorithm for k-LocVRP, for any constant ε>0....

  15. Coordinated Platoon Routing in a Metropolitan Network

    Energy Technology Data Exchange (ETDEWEB)

    Larson, Jeffrey; Munson, Todd; Sokolov, Vadim

    2016-10-10

    Platooning vehicles—connected and automated vehicles traveling with small intervehicle distances—use less fuel because of reduced aerodynamic drag. Given a network de- fined by vertex and edge sets and a set of vehicles with origin/destination nodes/times, we model and solve the combinatorial optimization problem of coordinated routing of vehicles in a manner that routes them to their destination on time while using the least amount of fuel. Common approaches decompose the platoon coordination and vehicle routing into separate problems. Our model addresses both problems simultaneously to obtain the best solution. We use modern modeling techniques and constraints implied from analyzing the platoon routing problem to address larger numbers of vehicles and larger networks than previously considered. While the numerical method used is unable to certify optimality for candidate solutions to all networks and parameters considered, we obtain excellent solutions in approximately one minute for much larger networks and vehicle sets than previously considered in the literature.

  16. Human BDCM Mulit-Route PBPK Model

    Data.gov (United States)

    U.S. Environmental Protection Agency — This data set contains the code for the BDCM human multi-route model written in the programming language acsl. The final published manuscript is provided since it...

  17. Locating Depots for Capacitated Vehicle Routing

    DEFF Research Database (Denmark)

    Gørtz, Inge Li; Nagarajan, Viswanath

    2016-01-01

    depots, one for each vehicle, and compute routes for the vehicles so that all demands are satisfied and the total cost is minimized. Our main result is a constant-factor approximation algorithm for k-LocVRP. In obtaining this result, we introduce a common generalization of the k-median and minimum...... spanning tree problems (called k median forest), which might be of independent interest. We give a local-search based (3+ε)-approximation algorithm for k median forest, which leads to a (12+ε)-approximation algorithm for k-LocVRP, for any constant ε>0.......We study a location-routing problem in the context of capacitated vehicle routing. The input to the k-location capacitated vehicle routing problem (k-LocVRP) consists of a set of demand locations in a metric space and a fleet of k identical vehicles, each of capacity Q. The objective is to locate k...

  18. Dynamic Escape Routes for Naval Ships

    National Research Council Canada - National Science Library

    Villalonga, Francisco J

    2005-01-01

    This thesis addresses the problem of optimal evacuation of a naval ship. We propose the use of a dynamic escape-route system which employs a signaling system to adapt the emergency egress process to the instigating contingency...

  19. Pharmacokinetics of Alternative Administration Routes of Melatonin

    DEFF Research Database (Denmark)

    Zetner, D.; Andersen, L. P.H.; Rosenberg, J.

    2016-01-01

    Background: Melatonin is traditionally administered orally but has a poor and variable bioavailability. This study aims to present an overview of studies investigating the pharmacokinetics of alternative administration routes of melatonin. Methods: A systematic literature search was performed...... and included experimental or clinical studies, investigating pharmacokinetics of alternative administration routes of melatonin in vivo. Alternative administration routes were defined as all administration routes except oral and intravenous. Results: 10 studies were included in the review. Intranasal....... Subcutaneous injection of melatonin displayed a rapid absorption rate compared to oral administration. Conclusion: Intranasal administration of melatonin has a large potential, and more research in humans is warranted. Transdermal application of melatonin has a possible use in a local application, due to slow...

  20. A Canadian refiner's perspective of synthetic crudes

    International Nuclear Information System (INIS)

    Halford, T.L.; McIntosh, A.P.; Rasmussen

    1997-01-01

    Some of the factors affecting a refiner's choice of crude oil include refinery hardware, particularly gas oil crackers, products slate and product specifications, crude availability, relative crude price and crude quality. An overview of synthetic crude, the use of synthetic crude combined with other crudes and a comparison of synthetic crude with conventional crude oil was given. The two main users of synthetic crude are basically two groups of refiners, those large groups who use synthetic crude combined with other crudes, and a smaller group who run synthetic crude on specially designed units as a sole feed. The effects of changes in fuel legislation were reviewed. It was predicted that the changes will have a mixed impact on the value of synthetic crude, but low sulphur diesel regulations and gasoline sulphur regulations will make current synthetic crudes attractive. The big future change with a negative impact will be diesel cetane increases to reduce engine emissions. This will reduce synthetic crude attractiveness due to distillate yields and quality and high gas oil yields. Similarly, any legislation limiting aromatics in diesel fuel will also make synthetic crudes less attractive. Problems experienced by refiners with hardware dedicated to synthetic crude (salt, naphthenic acid, fouling, quality variations) were also reviewed. 3 tabs

  1. Synthetic biology: Emerging bioengineering in Indonesia

    Science.gov (United States)

    Suhandono, Sony

    2017-05-01

    The development of synthetic biology will shape the new era of science and technology. It is an emerging bioengineering technique involving genetic engineering which can alter the phenotype and behavior of the cell or the new product. Synthetic biology may produce biomaterials, drugs, vaccines, biosensors, and even a recombinant secondary metabolite used in herbal and complementary medicine, such as artemisinin, a malaria drug which is usually extracted from the plant Artemisia annua. The power of synthetic biology has encouraged scientists in Indonesia, and is still in early development. This paper also covers some research from an Indonesian research institute in synthetic biology such as observing the production of bio surfactants and the enhanced production of artemisinin using a transient expression system. Synthetic biology development in Indonesia may also be related to the iGEM competition, a large synthetic biology research competition which was attended by several universities in Indonesia. The application of synthetic biology for drug discovery will be discussed.

  2. Printability of Synthetic Papers by Electrophotography

    Directory of Open Access Journals (Sweden)

    Rozália Szentgyörgyvölgyi

    2010-04-01

    Full Text Available This paper deals with the printability of synthetic papers by the electrophotography technique. Prints of cmyk colour fields from 20% to 100% raster tone values were printed on three types of synthetic papers (one film synthetic paper and two fiber synthetic papers. The investigation of the appearance included densitometric measurement of the cmyk prints. The results have shown differences in the optical density and optical tone value between cmyk prints made on various synthetic papers. The highest optical density and the increase of the optical tone value were observed on the film synthetic paper, where cmyk prints were more saturated. The highest abrasion resistance of cmyk prints was obtained from the fibre synthetic paper.

  3. Ising model for packet routing control

    International Nuclear Information System (INIS)

    Horiguchi, Tsuyoshi; Takahashi, Hideyuki; Hayashi, Keisuke; Yamaguchi, Chiaki

    2004-01-01

    For packet routing control in computer networks, we propose an Ising model which is defined in order to express competition among a queue length and a distance from a node with a packet to its destination node. By introducing a dynamics for a mean-field value of an Ising spin, we show by computer simulations that effective control of packet routing through priority links is possible

  4. Efficient Networks Communication Routing Using Swarm Intelligence

    OpenAIRE

    Koushal Kumar

    2012-01-01

    As demonstrated by natural biological swarm’s collective intelligence has an abundance of desirable properties for problem-solving like in network routing. The focus of this paper is in the applications of swarm based intelligence in information routing for communication networks. As we know networks are growing and adopting new platforms as new technologies comes. Also according to new demands and requirements networks topologies and its complexity is increasing with time. Thus it is becomin...

  5. Learning Points and Routes to Recommend Trajectories

    OpenAIRE

    Chen, Dawei; Ong, Cheng Soon; Xie, Lexing

    2016-01-01

    The problem of recommending tours to travellers is an important and broadly studied area. Suggested solutions include various approaches of points-of-interest (POI) recommendation and route planning. We consider the task of recommending a sequence of POIs, that simultaneously uses information about POIs and routes. Our approach unifies the treatment of various sources of information by representing them as features in machine learning algorithms, enabling us to learn from past behaviour. Info...

  6. Self-Interested Routing in Queueing Networks

    OpenAIRE

    Ali K. Parlaktürk; Sunil Kumar

    2004-01-01

    We study self-interested routing in stochastic networks, taking into account the discrete stochastic dynamics of such networks. We analyze a two-station multiclass queueing network in which the system manager chooses the scheduling rule and individual customers choose routes in a self-interested manner. We show that this network can be unstable in Nash equilibrium under some scheduling rules. We also design a nontrivial scheduling rule that negates the performance degradation resulting from s...

  7. Nitric oxide reduction over a synthetic coal char

    Energy Technology Data Exchange (ETDEWEB)

    C. Pevida; A. Arenillas; F. Rubiera; J.J. Pis [Instituto Nacional del Carbon, CSIC, Oviedo (Spain)

    2003-07-01

    In the present work, the mechanisms involved in the NO heterogeneous reduction have been investigated. A synthetic coal char was used as the carbon source. This synthetic coal was made from a mixture of model compounds and provides well-known functionalities, including nitrogenated ones, similar to those found in a high volatile bituminous coal. The char was obtained by pyrolysis of the synthetic coal, up to 1123 K, under helium atmosphere in a fixed bed reactor. Char texture and structure were characterised by N{sub 2} and CO{sub 2} adsorption isotherms at 77 and 273 K, respectively, X-ray diffraction, immersion calorimetry in C{sub 6}H{sub 6} and scanning electron microscopy (SEM). Temperature programmed reactions (TPR) were carried out in a thermogravimetric analyser using 400 ppm NO diluted in Ar as the reactant gas. The char was heated at 15 K min{sup -1} from room temperature to 1273 K. Gaseous products were simultaneously analysed by mass spectrometry (MS) and Fourier transform infrared spectroscopy (FTIR). The influence of nitrogen in the solid phase on the reduction mechanism was evaluated by comparing the results for chars with and without nitrogen in their composition. The results of this preliminary study showed that the presence of nitrogen in the chars composition did not favour the heterogeneous NO reduction. In addition, low temperature NO chemisorption on the carbon surface creates complexes that take an active part in the subsequent reactions with NO. 5 refs., 4 figs., 3 tabs.

  8. Optical spectroscopy and high pressure on emeralds: synthetic and natural

    Science.gov (United States)

    Sánchez-Alejo, M. A.; Hernández-Alcántara, J. M.; Flores Jiménez, C.; Calderón, T.; Murrieta S., H.; Camarillo García, E.

    2011-09-01

    Emerald, natural and synthetic, are the subject of study by means of optical spectroscopy techniques. Particularly, natural emeralds have been considered as a gemstone in jewelry not being so the synthetic ones. But, in general, the properties of these are very good for applications, for instance as a laser system, due to the impurities control. In this work a comparison between natural and synthetic emeralds is done. Chromium ions are the main responsible of the characteristic fascinating green color of these gemstones, entering in the crystals in octahedral sites. Absorption at room temperature show up two broad bands in the visible region and two narrow bands called the R-lines. That spectrum corresponds to trivalent chromium ions in an octahedral site, as it happens in ruby and alexandrite. On other hand, photoemission arises in the range 640-850 nm. at room temperature . It is shown that the luminescence spectra changes as the temperature is lowered. The effect on the main peak of luminescence when high pressure is applied on small samples of emerald shows as a linear function.

  9. Route selection issues for NWPA shipments

    International Nuclear Information System (INIS)

    Hill, C.V.; Harrison, I.G.

    1993-01-01

    Questions surrounding the designation of routes for the movement of spent nuclear fuel (SNF) and high-level radioactive waste (HLW) by the Office of Civilian Radioactive Waste Management (OCRWM) have broad implications. Federal regulations prescribe rules to be applied in the selection of highway routes. In most cases, these rules will lead to a clear selection of one route between an origin and destination point. However, in other cases, strict application of the regulations does not result in a clear choice of a preferred route. The regulations also provide discretion to State governments and carriers to select alternative routes to enhance the safety of the shipment. Railroad shipments of radioactive materials are not subject to Federal routing regulations. Since the railroads operate on private property, it has been assumed that they know the best way to move freight on their system. This discretion, while desirable for addressing unique local safety concerns or for responding to temporary safety concerns such as road problems, weather conditions, or construction areas, leads to significant opportunity for misunderstandings and uneasiness on the part of local residents

  10. The Route Analysis Based On Flight Plan

    Science.gov (United States)

    Feriyanto, Nur; Saleh, Chairul; Fauzi, Achmad; Rachman Dzakiyullah, Nur; Riza Iwaputra, Kahfi

    2016-02-01

    Economic development effects use of air transportation since the business process in every aspect was increased. Many people these days was prefer using airplane because it can save time and money. This situation also effects flight routes, many airlines offer new routes to deal with competition. Managing flight routes is one of the problems that must be faced in order to find the efficient and effective routes. This paper investigates the best routes based on flight performance by determining the amount of block fuel for the Jakarta-Denpasar flight route. Moreover, in this work compares a two kinds of aircraft and tracks by calculating flight distance, flight time and block fuel. The result shows Jakarta-Denpasar in the Track II has effective and efficient block fuel that can be performed by Airbus 320-200 aircraft. This study can contribute to practice in making an effective decision, especially helping executive management of company due to selecting appropriate aircraft and the track in the flight plan based on the block fuel consumption for business operation.

  11. Semiconductor thin films directly from minerals—study of structural, optical, and transport characteristics of Cu2O thin films from malachite mineral and synthetic CuO

    International Nuclear Information System (INIS)

    Balasubramaniam, K.R.; Kao, V.M.; Ravichandran, J.; Rossen, P.B.; Siemons, W.; Ager, J.W.

    2012-01-01

    We demonstrate the proof-of-concept of using an abundantly occurring natural ore, malachite (Cu 2 CO 3 (OH) 2 ) to directly yield the semiconductor Cu 2 O to be used as an active component of a functional thin film based device. Cu 2 O is an archetype hole-conducting semiconductor that possesses several interesting characteristics particularly useful for solar cell applications, including low cost, non-toxicity, good hole mobility, large minority carrier diffusion length, and a direct energy gap ideal for efficient absorption. In this article, we compare the structural, optical, and electrical transport characteristics of Cu 2 O thin films grown from the natural mineral malachite and synthetic CuO targets. Growth from either source material results in single-phase, fully epitaxial cuprous oxide thin films as determined by x-ray diffraction. The films grown from malachite have strong absorption coefficients ( 10 4 cm −1 ), a direct allowed optical bandgap ( 2.4 eV), and majority carrier hole mobilities ( 35 cm 2 V −1 s −1 at room temperature) that compare well with films grown from the synthetic target as well as with previously reported values. Our work demonstrates that minerals could be useful to directly yield the active components in functional devices and suggests a route for the exploration of low cost energy conversion and storage technologies. - Highlights: ► Semiconductor thin films directly from minerals ► Chemistry and structure evolution of the films obtained from mineral target is very similar to that films obtained from high-purity synthetic targets. ► Quite interestingly, transport and optical characteristics are also found to be similar.

  12. Pseudo-Cycle-Based Multicast Routing in Wormhole-Routed Networks

    Institute of Scientific and Technical Information of China (English)

    SONG JianPing (宋建平); HOU ZiFeng (侯紫峰); XU Ming (许铭)

    2003-01-01

    This paper addresses the problem of fault-tolerant multicast routing in wormholerouted multicomputers. A new pseudo-cycle-based routing method is presented for constructing deadlock-free multicast routing algorithms. With at most two virtual channels this technique can be applied to any connected networks with arbitrary topologies. Simulation results show that this technique results in negligible performance degradation even in the presence of a large number of faulty nodes.

  13. SAFEBIKE: A Bike-sharing Route Recommender with Availability Prediction and Safe Routing

    OpenAIRE

    Zhong, Weisheng; Chen, Fanglan; Fu, Kaiqun; Lu, Chang-Tien

    2017-01-01

    This paper presents SAFEBIKE, a novel route recommendation system for bike-sharing service that utilizes station information to infer the number of available bikes in dock and recommend bike routes according to multiple factors such as distance and safety level. The system consists of a station level availability predictor that predicts bikes and docks amount at each station, and an efficient route recommendation service that considers safety and bike/dock availability factors. It targets use...

  14. An electrolytic route to fusion?

    International Nuclear Information System (INIS)

    Anon.

    1992-01-01

    A patent has been granted by the Swedish Patent Authority for a new process to initiate and control energy generation through fusion reactions of hydrogen. According to the patent-holder, the Swedish company AB Technology Development, the fusion power process could be available for commercial applications within 4-5 years if laboratory and pilot plant tests prove successful. The new process employs a high voltage discharge in heavy water to create conditions under which, according to the patent holder, a high probability of fusion is achieved without the extraordinary high temperatures required in a conventional fusion reactor. (author)

  15. Synthetic Aperture Vector Flow Imaging

    DEFF Research Database (Denmark)

    Villagómez Hoyos, Carlos Armando

    The main objective of this project was to continue the development of a synthetic aperture vector flow estimator. This type of estimator is capable of overcoming two of the major limitations in conventional ultrasound systems: 1) the inability to scan large region of interest with high temporal......, this thesis showed that novel information can be obtained with vector velocity methods providing quantitative estimates of blood flow and insight into the complexity of the hemodynamics dynamics. This could give the clinician a new tool in assessment and treatment of a broad range of diseases....

  16. Synthetic Biology Guides Biofuel Production

    Directory of Open Access Journals (Sweden)

    Michael R. Connor

    2010-01-01

    Full Text Available The advancement of microbial processes for the production of renewable liquid fuels has increased with concerns about the current fuel economy. The development of advanced biofuels in particular has risen to address some of the shortcomings of ethanol. These advanced fuels have chemical properties similar to petroleum-based liquid fuels, thus removing the need for engine modification or infrastructure redesign. While the productivity and titers of each of these processes remains to be improved, progress in synthetic biology has provided tools to guide the engineering of these processes through present and future challenges.

  17. A route to hydroxylfluorenes: TsOH-mediated condensation reactions of 1,3-diketones with propargylic alcohols

    KAUST Repository

    Yao, Liangfeng

    2012-01-01

    An efficient method of preparing hydroxylfluorenes by TsOH-mediated tandem alkylation/rearrangements of propargylic alcohols with 1,3-diketones is described. These reactions are accomplished in moderate to good yields under mild conditions to offer a straightforward and convenient one step synthetic route to hydroxylfluorene derivatives through a plausible mechanism involving a sequence of dehydration, addition, rearrangement and aromatization. This journal is © The Royal Society of Chemistry 2012.

  18. Transportation routing analysis geographic information system -- TRAGIS, a multimodal transportation routing tool

    International Nuclear Information System (INIS)

    Johnson, P.E.

    1995-01-01

    Over 15 years ago, Oak Ridge National Laboratory (ORNL) developed two transportation routing models: HIGHWAY, which predicts truck transportation routes, and INTERLINE, which predicts rail transportation routes. Subsequent modifications have been made to enhance each of these models. Some of these changes include population density information for routes, HM-164 routing regulations for highway route controlled quantities of radioactive materials (RAM) truck shipments, and inclusion of waterway routing into INTERLINE. The AIRPORT model, developed 2 years after the HIGHWAY and INTERLINE models, serves as an emergency response tool. This model identifies the nearest airports from a designated location. Currently, the AIRPORT model is inactive. The Transportation Management Division of the US Department of Energy held a Baseline Requirements Assessment Session on the HIGHWAY, INTERLINE, and AIRPORT models in April 1994 to bring together many users of these models and other experts in the transportation routing field to discuss these models and to decide on the capabilities that needed to be added. Of the many needs discussed, the primary one was to have the network databases within a geographic information system (GIS). As a result of the Baseline Requirements Session, the development of a new GIS model has been initiated. This paper will discuss the development of the new Transportation Routing Analysis GIS (TRAGIS) model at ORNL

  19. Bellman Ford algorithm - in Routing Information Protocol (RIP)

    Science.gov (United States)

    Krianto Sulaiman, Oris; Mahmud Siregar, Amir; Nasution, Khairuddin; Haramaini, Tasliyah

    2018-04-01

    In a large scale network need a routing that can handle a lot number of users, one of the solutions to cope with large scale network is by using a routing protocol, There are 2 types of routing protocol that is static and dynamic, Static routing is manually route input based on network admin, while dynamic routing is automatically route input formed based on existing network. Dynamic routing is efficient used to network extensively because of the input of route automatic formed, Routing Information Protocol (RIP) is one of dynamic routing that uses the bellman-ford algorithm where this algorithm will search for the best path that traversed the network by leveraging the value of each link, so with the bellman-ford algorithm owned by RIP can optimize existing networks.

  20. Cell-free synthetic biology: thinking outside the cell.

    Science.gov (United States)

    Hodgman, C Eric; Jewett, Michael C

    2012-05-01

    Cell-free synthetic biology is emerging as a powerful approach aimed to understand, harness, and expand the capabilities of natural biological systems without using intact cells. Cell-free systems bypass cell walls and remove genetic regulation to enable direct access to the inner workings of the cell. The unprecedented level of control and freedom of design, relative to in vivo systems, has inspired the rapid development of engineering foundations for cell-free systems in recent years. These efforts have led to programmed circuits, spatially organized pathways, co-activated catalytic ensembles, rational optimization of synthetic multi-enzyme pathways, and linear scalability from the micro-liter to the 100-liter scale. It is now clear that cell-free systems offer a versatile test-bed for understanding why nature's designs work the way they do and also for enabling biosynthetic routes to novel chemicals, sustainable fuels, and new classes of tunable materials. While challenges remain, the emergence of cell-free systems is poised to open the way to novel products that until now have been impractical, if not impossible, to produce by other means. Copyright © 2011 Elsevier Inc. All rights reserved.

  1. MIDAS: A Modular DNA Assembly System for Synthetic Biology.

    Science.gov (United States)

    van Dolleweerd, Craig J; Kessans, Sarah A; Van de Bittner, Kyle C; Bustamante, Leyla Y; Bundela, Rudranuj; Scott, Barry; Nicholson, Matthew J; Parker, Emily J

    2018-04-20

    A modular and hierarchical DNA assembly platform for synthetic biology based on Golden Gate (Type IIS restriction enzyme) cloning is described. This enabling technology, termed MIDAS (for Modular Idempotent DNA Assembly System), can be used to precisely assemble multiple DNA fragments in a single reaction using a standardized assembly design. It can be used to build genes from libraries of sequence-verified, reusable parts and to assemble multiple genes in a single vector, with full user control over gene order and orientation, as well as control of the direction of growth (polarity) of the multigene assembly, a feature that allows genes to be nested between other genes or genetic elements. We describe the detailed design and use of MIDAS, exemplified by the reconstruction, in the filamentous fungus Penicillium paxilli, of the metabolic pathway for production of paspaline and paxilline, key intermediates in the biosynthesis of a range of indole diterpenes-a class of secondary metabolites produced by several species of filamentous fungi. MIDAS was used to efficiently assemble a 25.2 kb plasmid from 21 different modules (seven genes, each composed of three basic parts). By using a parts library-based system for construction of complex assemblies, and a unique set of vectors, MIDAS can provide a flexible route to assembling tailored combinations of genes and other genetic elements, thereby supporting synthetic biology applications in a wide range of expression hosts.

  2. Tracking the emergence of synthetic biology.

    Science.gov (United States)

    Shapira, Philip; Kwon, Seokbeom; Youtie, Jan

    2017-01-01

    Synthetic biology is an emerging domain that combines biological and engineering concepts and which has seen rapid growth in research, innovation, and policy interest in recent years. This paper contributes to efforts to delineate this emerging domain by presenting a newly constructed bibliometric definition of synthetic biology. Our approach is dimensioned from a core set of papers in synthetic biology, using procedures to obtain benchmark synthetic biology publication records, extract keywords from these benchmark records, and refine the keywords, supplemented with articles published in dedicated synthetic biology journals. We compare our search strategy with other recent bibliometric approaches to define synthetic biology, using a common source of publication data for the period from 2000 to 2015. The paper details the rapid growth and international spread of research in synthetic biology in recent years, demonstrates that diverse research disciplines are contributing to the multidisciplinary development of synthetic biology research, and visualizes this by profiling synthetic biology research on the map of science. We further show the roles of a relatively concentrated set of research sponsors in funding the growth and trajectories of synthetic biology. In addition to discussing these analyses, the paper notes limitations and suggests lines for further work.

  3. High temperature fatigue behaviour of intermetallics

    Indian Academy of Sciences (India)

    M. Senthilkumar (Newgen Imaging) 1461 1996 Oct 15 13:05:22

    The effect of processing route on strain-controlled low cycle fatigue (LCF) life of binary ..... the once regarding close control of composition, control and reproduction of ... inverse effect of temperature on fatigue life seen in tests conducted in air.

  4. DNA recognition by synthetic constructs.

    Science.gov (United States)

    Pazos, Elena; Mosquera, Jesús; Vázquez, M Eugenio; Mascareñas, José L

    2011-09-05

    The interaction of transcription factors with specific DNA sites is key for the regulation of gene expression. Despite the availability of a large body of structural data on protein-DNA complexes, we are still far from fully understanding the molecular and biophysical bases underlying such interactions. Therefore, the development of non-natural agents that can reproduce the DNA-recognition properties of natural transcription factors remains a major and challenging goal in chemical biology. In this review we summarize the basics of double-stranded DNA recognition by transcription factors, and describe recent developments in the design and preparation of synthetic DNA binders. We mainly focus on synthetic peptides that have been designed by following the DNA interaction of natural proteins, and we discuss how the tools of organic synthesis can be used to make artificial constructs equipped with functionalities that introduce additional properties to the recognition process, such as sensing and controllability. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Synthetic Biology of Polyhydroxyalkanoates (PHA).

    Science.gov (United States)

    Meng, De-Chuan; Chen, Guo-Qiang

    Microbial polyhydroxyalkanoates (PHA) are a family of biodegradable and biocompatible polyesters which have been extensively studied using synthetic biology and metabolic engineering methods for improving production and for widening its diversity. Synthetic biology has allowed PHA to become composition controllable random copolymers, homopolymers, and block copolymers. Recent developments showed that it is possible to establish a microbial platform for producing not only random copolymers with controllable monomers and their ratios but also structurally defined homopolymers and block copolymers. This was achieved by engineering the genome of Pseudomonas putida or Pseudomonas entomophiles to weaken the β-oxidation and in situ fatty acid synthesis pathways, so that a fatty acid fed to the bacteria maintains its original chain length and structures when incorporated into the PHA chains. The engineered bacterium allows functional groups in a fatty acid to be introduced into PHA, forming functional PHA, which, upon grafting, generates endless PHA variety. Recombinant Escherichia coli also succeeded in producing efficiently poly(3-hydroxypropionate) or P3HP, the strongest member of PHA. Synthesis pathways of P3HP and its copolymer P3HB3HP of 3-hydroxybutyrate and 3-hydroxypropionate were assembled respectively to allow their synthesis from glucose. CRISPRi was also successfully used to manipulate simultaneously multiple genes and control metabolic flux in E. coli to obtain a series of copolymer P3HB4HB of 3-hydroxybutyrate (3HB) and 4-hydroxybutyrate (4HB). The bacterial shapes were successfully engineered for enhanced PHA accumulation.

  6. Vectoring of parallel synthetic jets

    Science.gov (United States)

    Berk, Tim; Ganapathisubramani, Bharathram; Gomit, Guillaume

    2015-11-01

    A pair of parallel synthetic jets can be vectored by applying a phase difference between the two driving signals. The resulting jet can be merged or bifurcated and either vectored towards the actuator leading in phase or the actuator lagging in phase. In the present study, the influence of phase difference and Strouhal number on the vectoring behaviour is examined experimentally. Phase-locked vorticity fields, measured using Particle Image Velocimetry (PIV), are used to track vortex pairs. The physical mechanisms that explain the diversity in vectoring behaviour are observed based on the vortex trajectories. For a fixed phase difference, the vectoring behaviour is shown to be primarily influenced by pinch-off time of vortex rings generated by the synthetic jets. Beyond a certain formation number, the pinch-off timescale becomes invariant. In this region, the vectoring behaviour is determined by the distance between subsequent vortex rings. We acknowledge the financial support from the European Research Council (ERC grant agreement no. 277472).

  7. Synthetic membrane-targeted antibiotics.

    Science.gov (United States)

    Vooturi, S K; Firestine, S M

    2010-01-01

    Antimicrobial resistance continues to evolve and presents serious challenges in the therapy of both nosocomial and community-acquired infections. The rise of resistant strains like methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant Staphylococcus aureus (VRSA) and vancomycin-resistant enterococci (VRE) suggests that antimicrobial resistance is an inevitable evolutionary response to antimicrobial use. This highlights the tremendous need for antibiotics against new bacterial targets. Agents that target the integrity of bacterial membrane are relatively novel in the clinical armamentarium. Daptomycin, a lipopeptide is a classical example of membrane-bound antibiotic. Nature has also utilized this tactic. Antimicrobial peptides (AMPs), which are found in all kingdoms, function primarily by permeabilizing the bacterial membrane. AMPs have several advantages over existing antibiotics including a broad spectrum of activity, rapid bactericidal activity, no cross-resistance with the existing antibiotics and a low probability for developing resistance. Currently, a small number of peptides have been developed for clinical use but therapeutic applications are limited because of poor bioavailability and high manufacturing cost. However, their broad specificity, potent activity and lower probability for resistance have spurred the search for synthetic mimetics of antimicrobial peptides as membrane-active antibiotics. In this review, we will discuss the different classes of synthetic membrane-bound antibiotics published since 2004.

  8. Synthetic vision display evaluation studies

    Science.gov (United States)

    Regal, David M.; Whittington, David H.

    1994-01-01

    The goal of this research was to help us understand the display requirements for a synthetic vision system for the High Speed Civil Transport (HSCT). Four experiments were conducted to examine the effects of different levels of perceptual cue complexity in displays used by pilots in a flare and landing task. Increased levels of texture mapping of terrain and runway produced mixed results, including harder but shorter landings and a lower flare initiation altitude. Under higher workload conditions, increased texture resulted in an improvement in performance. An increase in familiar size cues did not result in improved performance. Only a small difference was found between displays using two patterns of high resolution texture mapping. The effects of increased perceptual cue complexity on performance was not as strong as would be predicted from the pilot's subjective reports or from related literature. A description of the role of a synthetic vision system in the High Speed Civil Transport is provide along with a literature review covering applied research related to perceptual cue usage in aircraft displays.

  9. On the chemical synthesis route to bulk-scale skutterudite materials

    DEFF Research Database (Denmark)

    Tafti, Mohsen Y.; Saleemi, Mohsin; Han, Li

    2016-01-01

    In this article an alternative high yield route for the synthesis of CoSb3-based unfilled skutterudites is presented. Using low-melting temperature salts of the constituents, melting and mixing them homogeneously in a hydrophobic liquid with postprocessing of the powders we achieve a more intimat......, compaction of the powders with SPS technique provided a safe route to maintaining the nanopowder size and achieving low thermal conductivity (3 W/mK). The proposed method can easily be scaled up and adopted by the industry.......In this article an alternative high yield route for the synthesis of CoSb3-based unfilled skutterudites is presented. Using low-melting temperature salts of the constituents, melting and mixing them homogeneously in a hydrophobic liquid with postprocessing of the powders we achieve a more...

  10. Salinity, temperature, oxygen, sediment characterization, hydrocarbon characterization, heavy metal contaminant concentration, total organic carbon, porewater chemistry, and infaunal taxonomic identifications and counts collected during the Gulf of Mexico Comprehensive Synthetic Based Muds Monitoring Program between July 29, 2000 and May 20, 2002 (NODC Accession 0069470)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The objective of this study was to assess the fate and physical, chemical, and biological effects of synthetic based drilling mud cuttings discharged from offshore...

  11. Recovery of Actinides from Actinide-Aluminium Alloys: Chlorination Route

    International Nuclear Information System (INIS)

    Mendes, E.; Malmbeck, R.; Soucek, P.; Jardin, R.; Glatz, J.P.; Cassayre, L.

    2008-01-01

    A method for recovery of actinides (An) from An-Al alloys formed by electrochemical separation of metallic spent nuclear fuel on solid aluminium electrodes in molten chloride salts is described. The proposed route consists of three main steps: -) vacuum distillation of salt adhered on the electrodes, -) chlorination of An-Al alloy by pure chlorine gas and -) sublimation of formed AlCl 3 . A thermochemical study of the route was performed to determine important chemical reactions and to find optimum experimental conditions for all process steps. Vacuum distillation of the electrode is efficient for complete removal of remaining salt and most fission products, full chlorination of the An-Al alloys is possible at any working temperature and evaporation of AlCl 3 is achieved by heating under argon. Experiments have been carried out using U-Al alloy in order to define parameters providing full alloy chlorination without formation of volatile UCl 5 and UCl 6 . It was shown that full chlorination of An-Al alloys without An losses should be possible at a temperature approx. 150 deg. C. (authors)

  12. Recovery of Actinides from Actinide-Aluminium Alloys: Chlorination Route

    Energy Technology Data Exchange (ETDEWEB)

    Mendes, E.; Malmbeck, R.; Soucek, P.; Jardin, R.; Glatz, J.P. [European Commission, JRC, Institute for Transuranium Elements, Postfach 2340, 76125 Karlsruhe (Germany); Cassayre, L. [Laboratoire de Genie Chimique (LGC), Universite Paul Sabatier, UMR CNRS 5503, 118 route de Narbonne, 31062 Toulouse Cedex 04 (France)

    2008-07-01

    A method for recovery of actinides (An) from An-Al alloys formed by electrochemical separation of metallic spent nuclear fuel on solid aluminium electrodes in molten chloride salts is described. The proposed route consists of three main steps: -) vacuum distillation of salt adhered on the electrodes, -) chlorination of An-Al alloy by pure chlorine gas and -) sublimation of formed AlCl{sub 3}. A thermochemical study of the route was performed to determine important chemical reactions and to find optimum experimental conditions for all process steps. Vacuum distillation of the electrode is efficient for complete removal of remaining salt and most fission products, full chlorination of the An-Al alloys is possible at any working temperature and evaporation of AlCl{sub 3} is achieved by heating under argon. Experiments have been carried out using U-Al alloy in order to define parameters providing full alloy chlorination without formation of volatile UCl{sub 5} and UCl{sub 6}. It was shown that full chlorination of An-Al alloys without An losses should be possible at a temperature approx. 150 deg. C. (authors)

  13. Bubble-point pressures of some selected methane + synthetic C{sub 6+} mixtures

    Energy Technology Data Exchange (ETDEWEB)

    Shariati, A.; Moshfeghian, M. [Shiraz Univ. (Iran, Islamic Republic of). Dept. of Chemical Engineering; Peters, C.J. [Delft Univ. of Technology (Netherlands). Lab. of Applied Thermodynamics and Phase Equilibria

    1998-03-01

    In this work, a series of bubble-point measurements were carried out on some synthetic C{sub 6+} mixtures in the presence of methane. These synthetic mixtures included alkanes, cycloalkanes, and aromatics. The experiments were carried out using the Cailletet apparatus, and bubble-point pressures were measured in a temperature range of 311--470 K. The corresponding pressures were predicted using the Peng-Robinson equation of state, and the relative errors were estimated. It is shown that such synthetic C{sub 6+} mixtures can be simulated reasonably well by this equation of state.

  14. Towards seasonal Arctic shipping route predictions

    Science.gov (United States)

    Haines, K.; Melia, N.; Hawkins, E.; Day, J. J.

    2017-12-01

    In our previous work [1] we showed how trans-Arctic shipping routes would become more available through the 21st century as sea ice declines, using CMIP5 models with means and stds calibrated to PIOMAS sea ice observations. Sea ice will continue to close shipping routes to open water vessels through the winter months for the foreseeable future so the availability of open sea routes will vary greatly from year to year. Here [2] we look at whether the trans-Arctic shipping season period can be predicted in seasonal forecasts, again using several climate models, and testing both perfect and imperfect knowledge of the initial sea ice conditions. We find skilful predictions of the upcoming summer shipping season can be made from as early as January, although typically forecasts may show lower skill before a May `predictability barrier'. Focussing on the northern sea route (NSR) off Siberia, the date of opening of this sea route is twice as variable as the closing date, and this carries through to reduced predictability at the start of the season. Under climate change the later freeze-up date accounts for 60% of the lengthening season, Fig1 We find that predictive skill is state dependent with predictions for high or low ice years exhibiting greater skill than for average ice years. Forecasting the exact timing of route open periods is harder (more weather dependent) under average ice conditions while in high and low ice years the season is more controlled by the initial ice conditions from spring onwards. This could be very useful information for companies planning vessel routing for the coming season. We tested this dependence on the initial ice conditions by changing the initial ice state towards climatologically average conditions and show directly that early summer sea-ice thickness information is crucial to obtain skilful forecasts of the coming shipping season. Mechanisms for this are discussed. This strongly suggests that good sea ice thickness observations

  15. Word selection affects perceptions of synthetic biology

    Directory of Open Access Journals (Sweden)

    Tonidandel Scott

    2011-07-01

    Full Text Available Abstract Members of the synthetic biology community have discussed the significance of word selection when describing synthetic biology to the general public. In particular, many leaders proposed the word "create" was laden with negative connotations. We found that word choice and framing does affect public perception of synthetic biology. In a controlled experiment, participants perceived synthetic biology more negatively when "create" was used to describe the field compared to "construct" (p = 0.008. Contrary to popular opinion among synthetic biologists, however, low religiosity individuals were more influenced negatively by the framing manipulation than high religiosity people. Our results suggest that synthetic biologists directly influence public perception of their field through avoidance of the word "create".

  16. Creating biological nanomaterials using synthetic biology

    International Nuclear Information System (INIS)

    Rice, MaryJoe K; Ruder, Warren C

    2014-01-01

    Synthetic biology is a new discipline that combines science and engineering approaches to precisely control biological networks. These signaling networks are especially important in fields such as biomedicine and biochemical engineering. Additionally, biological networks can also be critical to the production of naturally occurring biological nanomaterials, and as a result, synthetic biology holds tremendous potential in creating new materials. This review introduces the field of synthetic biology, discusses how biological systems naturally produce materials, and then presents examples and strategies for incorporating synthetic biology approaches in the development of new materials. In particular, strategies for using synthetic biology to produce both organic and inorganic nanomaterials are discussed. Ultimately, synthetic biology holds the potential to dramatically impact biological materials science with significant potential applications in medical systems. (review)

  17. Creating biological nanomaterials using synthetic biology.

    Science.gov (United States)

    Rice, MaryJoe K; Ruder, Warren C

    2014-02-01

    Synthetic biology is a new discipline that combines science and engineering approaches to precisely control biological networks. These signaling networks are especially important in fields such as biomedicine and biochemical engineering. Additionally, biological networks can also be critical to the production of naturally occurring biological nanomaterials, and as a result, synthetic biology holds tremendous potential in creating new materials. This review introduces the field of synthetic biology, discusses how biological systems naturally produce materials, and then presents examples and strategies for incorporating synthetic biology approaches in the development of new materials. In particular, strategies for using synthetic biology to produce both organic and inorganic nanomaterials are discussed. Ultimately, synthetic biology holds the potential to dramatically impact biological materials science with significant potential applications in medical systems.

  18. Properties of magnetically diluted nanocrystals prepared by mechanochemical route

    International Nuclear Information System (INIS)

    Balaz, P.; Skorvanek, I.; Fabian, M.; Kovac, J.; Steinbach, F.; Feldhoff, A.; Sepelak, V.; Jiang, J.; Satka, A.; Kovac, J.

    2010-01-01

    The bulk and surface properties of magnetically diluted Cd 0.6 Mn 0.4 S nanocrystals synthesized by solid state route in a planetary mill were studied. XRD, SEM, TEM (HRTEM), low-temperature N 2 sorption, nanoparticle size distribution as well as SQUID magnetometry methods have been applied. The measurements identified the aggregates of small nanocrystals, 5-10 nm in size. The homogeneity of produced particles with well developed specific surface area (15-66 m 2 g -1 ) was documented. The transition from the paramagnetic to the spin-glass-like phase has been observed below ∼40 K. The changes in the magnetic behaviour at low temperatures seem to be correlated with the formation of the new surface area as a consequence of milling. The magnetically diluted Cd 0.6 Mn 0.4 S nanocrystals are obtained in the simple synthesis step, making the process attractive for industrial applications.

  19. Alternative routes to olefins. Chances and challenges

    Energy Technology Data Exchange (ETDEWEB)

    Meiswinkel, A.; Delhomme, C.; Ponceau, M. [Linde AG, Pullach (Germany)

    2013-11-01

    In the future, conventional raw materials which are used for the production of olefins will get shorter and more expensive and alternative raw materials and production routes will gain importance. Natural gas, coal, shale oil or bio-mass are potential sources for the production of olefins, especially ethylene and propylene, as major base chemicals. Several potential production routes were already developed in the past, but cost, energy and environmental considerations might make these unattractive or unfeasible in comparison to traditional processes (e.g. steam cracking). Other processes such as methanol to olefins processes were successfully developed and first commercial units are running. In addition, combination of traditional processes (e.g. coal/biomass gasification, Fischer-Tropsch and steam cracking) might enable new pathways. Besides, dehydration of ethanol is opening direct routes from biomass to 'green' ethylene. However, for these 'bio-routes', feedstock availability and potential land use conflict with food production (sugar cane, wheat,..) still need to be evaluated. finally, new oxidative routes, including processes such as oxidative coupling of methane or oxidative dehydrogenation, are still at an early development stage but present potential for future industrial applications. (orig.) (Published in summary form only)

  20. An Indirect Route for Ethanol Production

    Energy Technology Data Exchange (ETDEWEB)

    Eggeman, T.; Verser, D.; Weber, E.

    2005-04-29

    The ZeaChem indirect method is a radically new approach to producing fuel ethanol from renewable resources. Sugar and syngas processing platforms are combined in a novel way that allows all fractions of biomass feedstocks (e.g. carbohydrates, lignins, etc.) to contribute their energy directly into the ethanol product via fermentation and hydrogen based chemical process technologies. The goals of this project were: (1) Collect engineering data necessary for scale-up of the indirect route for ethanol production, and (2) Produce process and economic models to guide the development effort. Both goals were successfully accomplished. The projected economics of the Base Case developed in this work are comparable to today's corn based ethanol technology. Sensitivity analysis shows that significant improvements in economics for the indirect route would result if a biomass feedstock rather that starch hydrolyzate were used as the carbohydrate source. The energy ratio, defined as the ratio of green energy produced divided by the amount of fossil energy consumed, is projected to be 3.11 to 12.32 for the indirect route depending upon the details of implementation. Conventional technology has an energy ratio of 1.34, thus the indirect route will have a significant environmental advantage over today's technology. Energy savings of 7.48 trillion Btu/yr will result when 100 MMgal/yr (neat) of ethanol capacity via the indirect route is placed on-line by the year 2010.

  1. Routing algorithms in networks-on-chip

    CERN Document Server

    Daneshtalab, Masoud

    2014-01-01

    This book provides a single-source reference to routing algorithms for Networks-on-Chip (NoCs), as well as in-depth discussions of advanced solutions applied to current and next generation, many core NoC-based Systems-on-Chip (SoCs). After a basic introduction to the NoC design paradigm and architectures, routing algorithms for NoC architectures are presented and discussed at all abstraction levels, from the algorithmic level to actual implementation.  Coverage emphasizes the role played by the routing algorithm and is organized around key problems affecting current and next generation, many-core SoCs. A selection of routing algorithms is included, specifically designed to address key issues faced by designers in the ultra-deep sub-micron (UDSM) era, including performance improvement, power, energy, and thermal issues, fault tolerance and reliability.   ·         Provides a comprehensive overview of routing algorithms for Networks-on-Chip and NoC-based, manycore systems; ·         Describe...

  2. Low Carbon Footprint Routes for Bird Watching

    Directory of Open Access Journals (Sweden)

    Wei-Ta Fang

    2015-03-01

    Full Text Available Bird watching is one of many recreational activities popular in ecotourism. Its popularity, therefore, prompts the need for studies on energy conservation. One such environmentally friendly approach toward minimizing bird watching’s ecological impact is ensuring a reduced carbon footprint by using an economic travel itinerary comprising a series of connected routes between tourist attractions that minimizes transit time. This study used a travel-route planning approach using geographic information systems to detect the shortest path, thereby solving the problems associated with time-consuming transport. Based on the results of road network analyses, optimal travel-route planning can be determined. These methods include simulated annealing (SA and genetic algorithms (GA. We applied two algorithms in our simulation research to detect which one is an appropriate algorithm for running carbon-routing algorithms at the regional scale. SA, which is superior to GA, is considered an excellent approach to search for the optimal path to reduce carbon dioxide and high gasoline fees, thereby controlling travel time by using the shortest travel routes.

  3. Sigma Routing Metric for RPL Protocol

    Directory of Open Access Journals (Sweden)

    Paul Sanmartin

    2018-04-01

    Full Text Available This paper presents the adaptation of a specific metric for the RPL protocol in the objective function MRHOF. Among the functions standardized by IETF, we find OF0, which is based on the minimum hop count, as well as MRHOF, which is based on the Expected Transmission Count (ETX. However, when the network becomes denser or the number of nodes increases, both OF0 and MRHOF introduce long hops, which can generate a bottleneck that restricts the network. The adaptation is proposed to optimize both OFs through a new routing metric. To solve the above problem, the metrics of the minimum number of hops and the ETX are combined by designing a new routing metric called SIGMA-ETX, in which the best route is calculated using the standard deviation of ETX values between each node, as opposed to working with the ETX average along the route. This method ensures a better routing performance in dense sensor networks. The simulations are done through the Cooja simulator, based on the Contiki operating system. The simulations showed that the proposed optimization outperforms at a high margin in both OF0 and MRHOF, in terms of network latency, packet delivery ratio, lifetime, and power consumption.

  4. Routing strategies in traffic network and phase transition in network ...

    Indian Academy of Sciences (India)

    The dynamics of information traffic over scale-free networks has been investigated systematically. A series of routing strategies of data packets have been proposed, including the local routing strategy, the next-nearest-neighbour routing strategy, and the mixed routing strategy based on local static and dynamic information.

  5. Beyond Traditional DTN Routing: Social Networks for Opportunistic Communication

    OpenAIRE

    Schurgot, Mary R.; Comaniciu, Cristina; Jaffrès-Runser, Katia

    2011-01-01

    This article examines the evolution of routing protocols for intermittently connected ad hoc networks and discusses the trend toward social-based routing protocols. A survey of current routing solutions is presented, where routing protocols for opportunistic networks are classified based on the network graph employed. The need to capture performance tradeoffs from a multi-objective perspective is highlighted.

  6. Synthetic approaches to uniform polymers.

    Science.gov (United States)

    Ali, Monzur; Brocchini, Steve

    2006-12-30

    Uniform polymers are characterised by a narrow molecular weight distribution (MWD). Uniformity is also defined by chemical structure in respect of (1) monomer orientation, sequence and stereo-regularity, (2) polymer shape and morphology and (3) chemical functionality. The function of natural polymers such as polypeptides and polynucleotides is related to their conformational structure (e.g. folded tertiary structure). This is only possible because of their high degree of uniformity. While completely uniform synthetic polymers are rare, polymers with broad structure and MWD are widely used in medicine and the biomedical sciences. They are integral components in final dosage forms, drug delivery systems (DDS) and in implantable devices. Increasingly uniform polymers are being used to develop more complex medicines (e.g. delivery of biopharmaceuticals, enhanced formulations or DDS's for existing actives). In addition to the function imparted by any new polymer it will be required to meet stringent specifications in terms of cost containment, scalability, biocompatibility and performance. Synthetic polymers with therapeutic activity are also being developed to exploit their polyvalent properties, which is not possible with low molecular weight molecules. There is need to utilise uniform polymers for applications where the polymer may interact with the systemic circulation, tissues or cellular environment. There are also potential applications (e.g. stimuli responsive coatings) where uniform polymers may be used for their more defined property profile. While it is not yet practical to prepare synthetic polymers to the same high degree of uniformity as proteins, nature also effectively utilises many polymers with lower degrees of uniformity (e.g. polysaccharides, poly(amino acids), polyhydroxyalkanoates). In recent years it has become possible to prepare with practical experimental protocols sufficient quantities of polymers that display many aspects of uniformity. This

  7. Children's route choice during active transportation to school: Difference between shortest and actual route

    NARCIS (Netherlands)

    Dessing, D.; Vries, S.I. de; Hegeman, G.; Verhagen, E.; Mechelen, W. van; Pierik, F.H.

    2016-01-01

    Background: The purpose of this study is to increase our understanding of environmental correlates that are associated with route choice during active transportation to school (ATS) by comparing characteristics of actual walking and cycling routes between home and school with the shortest possible

  8. Synthetic Lipoproteins as Carriers for Drug Delivery.

    Science.gov (United States)

    Huang, Gangliang; Liu, Yang; Huang, Hualiang

    2016-01-01

    Synthetic lipoprotein is an effective carrier of targeted delivery for drugs. It has the very small size, good biocompatibility, suitable half-life, and specific lipoprotein receptorbinding capacity. Compared with the traditional natural lipoprotein, synthetic lipoprotein not only retains the original biological characteristics and functions, but also exhibits the excellent characteristics in drug delivery. Herein, the advantages, development, applications, and prospect of synthetic lipoproteins as drug carriers were summarized.

  9. Geo synthetic-reinforced Pavement systems

    International Nuclear Information System (INIS)

    Zornberg, J. G.

    2014-01-01

    Geo synthetics have been used as reinforcement inclusions to improve pavement performance. while there are clear field evidence of the benefit of using geo synthetic reinforcements, the specific conditions or mechanisms that govern the reinforcement of pavements are, at best, unclear and have remained largely unmeasured. Significant research has been recently conducted with the objectives of: (i) determining the relevant properties of geo synthetics that contribute to the enhanced performance of pavement systems, (ii) developing appropriate analytical, laboratory and field methods capable of quantifying the pavement performance, and (iii) enabling the prediction of pavement performance as a function of the properties of the various types of geo synthetics. (Author)

  10. Veterans Affairs Suicide Prevention Synthetic Dataset

    Data.gov (United States)

    Department of Veterans Affairs — The VA's Veteran Health Administration, in support of the Open Data Initiative, is providing the Veterans Affairs Suicide Prevention Synthetic Dataset (VASPSD). The...

  11. Synthetic biology assemblies for sustainable space exploration

    Data.gov (United States)

    National Aeronautics and Space Administration — The work utilized synthetic biology to create sustainable food production processes by developing technology to efficiently convert inedible crop waste to...

  12. Guidelines for selecting preferred highway routes for highway-route-controlled quantity shipments of radioactive materials

    International Nuclear Information System (INIS)

    1989-01-01

    The document presents guidelines for use by State officials in selecting preferred routes for highway route controlled quantity shipments of radioactive materials. A methodology for analyzing and comparing safety factors of alternative routes is described. Technical information on the impacts of radioactive material transportation needed to apply the methodology is also presented. Application of the methodology will identify the route (or set of routes) that minimizes the radiological impacts from shipments of these radioactive materials within a given State. Emphasis in the document is on practical application of the methodology. Some details of the derivation of the methods and data are presented in the appendices. All references in the body of the report can be found listed in the Bibliography (Appendix F)

  13. Robust against route failure using power proficient reliable routing in MANET

    Directory of Open Access Journals (Sweden)

    M. Malathi

    2018-03-01

    Full Text Available The aim of this paper was to propose a novel routing protocol for Mobile Adhoc Network communication which reduces the route failure during transmission. The proposed routing protocol uses 3 salient parameters to discover the path which ensure the reliable communication. The quality of the channel, link quality and energy level of the node are the major reasons for unintentional node failure in mobile Adhoc network. So the proposed routing protocol considers these three parameters to select the best forwarder node in the path. The reliable data communication is achieved by transmitting data via path selected by the proposed routing scheme has been proven using network simulator (NS2. Keywords: Channel quality, Link quality, Mobile Adhoc Network (MANET, Residual energy

  14. Synthetic biology of antimicrobial discovery

    Science.gov (United States)

    Zakeri, Bijan; Lu, Timothy K.

    2012-01-01

    Antibiotic discovery has a storied history. From the discovery of penicillin by Sir Alexander Fleming to the relentless quest for antibiotics by Selman Waksman, the stories have become like folklore, used to inspire future generations of scientists. However, recent discovery pipelines have run dry at a time when multidrug resistant pathogens are on the rise. Nature has proven to be a valuable reservoir of antimicrobial agents, which are primarily produced by modularized biochemical pathways. Such modularization is well suited to remodeling by an interdisciplinary approach that spans science and engineering. Herein, we discuss the biological engineering of small molecules, peptides, and non-traditional antimicrobials and provide an overview of the growing applicability of synthetic biology to antimicrobials discovery. PMID:23654251

  15. Synthetic biology of antimicrobial discovery.

    Science.gov (United States)

    Zakeri, Bijan; Lu, Timothy K

    2013-07-19

    Antibiotic discovery has a storied history. From the discovery of penicillin by Sir Alexander Fleming to the relentless quest for antibiotics by Selman Waksman, the stories have become like folklore used to inspire future generations of scientists. However, recent discovery pipelines have run dry at a time when multidrug-resistant pathogens are on the rise. Nature has proven to be a valuable reservoir of antimicrobial agents, which are primarily produced by modularized biochemical pathways. Such modularization is well suited to remodeling by an interdisciplinary approach that spans science and engineering. Herein, we discuss the biological engineering of small molecules, peptides, and non-traditional antimicrobials and provide an overview of the growing applicability of synthetic biology to antimicrobials discovery.

  16. Synthetic biology: a utilitarian perspective.

    Science.gov (United States)

    Smith, Kevin

    2013-10-01

    I examine the positive and negative features of synthetic biology ('SynBio') from a utilitarian ethical perspective. The potential beneficial outcomes from SynBio in the context of medicine are substantial; however it is not presently possible to predict precise outcomes due to the nascent state of the field. Potential negative outcomes from SynBio also exist, including iatrogenesis and bioterrorism; however it is not yet possible to quantify these risks. I argue that the application of a 'precautionary' approach to SynBio is ethically fraught, as is the notion that SynBio-associated knowledge ought to be restricted. I conclude that utilitarians ought to support a broadly laissez-faire stance in respect of SynBio. © 2013 John Wiley & Sons Ltd.

  17. Synthetic biology: engineering molecular computers

    CERN Multimedia

    CERN. Geneva

    2018-01-01

    Complicated systems cannot survive the rigors of a chaotic environment, without balancing mechanisms that sense, decide upon and counteract the exerted disturbances. Especially so with living organisms, forced by competition to incredible complexities, escalating also their self-controlling plight. Therefore, they compute. Can we harness biological mechanisms to create artificial computing systems? Biology offers several levels of design abstraction: molecular machines, cells, organisms... ranging from the more easily-defined to the more inherently complex. At the bottom of this stack we find the nucleic acids, RNA and DNA, with their digital structure and relatively precise interactions. They are central enablers of designing artificial biological systems, in the confluence of engineering and biology, that we call Synthetic biology. In the first part, let us follow their trail towards an overview of building computing machines with molecules -- and in the second part, take the case study of iGEM Greece 201...

  18. Study of positron lifetime spectrum for Zn O varistor ceramics fabricated by Sol-gel route

    International Nuclear Information System (INIS)

    Li Xigui; Wei Shutao; Zhang Ruiying; Cheng Guosheng; Dai Xianqi; Zhang Jincang; Xing Huaimin

    2000-01-01

    An investigation of positron lifetime spectrum for ZnO varistor ceramics fabricated by Sol-gel route was carried out. The relationship between lifetime parameters and the densification and nonlinear coefficient α was given. The dependence of electrical properties on sintering temperature and duration was discussed

  19. Nanostructured aluminium oxide powders obtained by aspartic acid-nitrate gel-combustion routes

    Energy Technology Data Exchange (ETDEWEB)

    Gardey Merino, Maria Celeste, E-mail: mcgardey@frm.utn.edu.a [Laboratorio de Investigaciones y Servicios Ambientales Mendoza (LISAMEN) - CCT - CONICET, Avda. Ruiz Leal s/n, Parque Gral. San Martin, (M5502IRA) Ciudad de Mendoza, Prov. de Mendoza (Argentina); Grupo CLIOPE, Universidad Tecnologica Nacional - Facultad Regional Mendoza, Rodriguez 273, (M5502AJE) Ciudad de Mendoza, Prov. de Mendoza (Argentina); Lascalea, Gustavo E. [Laboratorio de Investigaciones y Servicios Ambientales Mendoza (LISAMEN) - CCT - CONICET, Avda. Ruiz Leal s/n, Parque Gral. San Martin, (M5502IRA) Ciudad de Mendoza, Prov. de Mendoza (Argentina); Sanchez, Laura M. [CINSO (Centro de Investigaciones en Solidos), CITEFA - CONICET, J.B. de La Salle 4397, (B1603ALO) Villa Martelli, Prov. de Buenos Aires (Argentina); Vazquez, Patricia G. [Centro de Investigacion y Desarrollo en Ciencias Aplicadas ' Dr. Jorge J. Ronco' (CINDECA), CONICET, Universidad Nacional de La Plata, Calle 47 nro. 257, (B1900AJK) La Plata, Prov. de Buenos Aires (Argentina); Cabanillas, Edgardo D. [CONICET and Centro Atomico Constituyentes, Comision Nacional de Energia Atomica, Gral. Paz 1499, (1650) San Martin, Prov. de Buenos Aires (Argentina); Lamas, Diego G. [CINSO (Centro de Investigaciones en Solidos), CITEFA - CONICET, J.B. de La Salle 4397, (B1603ALO) Villa Martelli, Prov. de Buenos Aires (Argentina)

    2010-04-16

    In this work, two new gel-combustion routes for the synthesis of Al{sub 2}O{sub 3} nanopowders with aspartic acid as fuel are presented. The first route is a conventional stoichiometric process, while the second one is a non-stoichiometric, pH-controlled process. These routes were compared with similar synthesis procedures using glycine as fuel, which are well-known in the literature. The samples were calcined in air at different temperatures, in a range of 600-1200 {sup o}C. They were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy and BET specific surface area. Different phases were obtained depending on the calcination temperature: amorphous, {gamma} (metastable) or {alpha} (stable). The amorphous-to-{gamma} transition was found for calcination temperatures in the range of 700-900 {sup o}C, while the {gamma}-to-{alpha} one was observed for calcination temperatures of 1100-1200 {sup o}C. The retention of the metastable {gamma} phase is probably due to a crystallite size effect. It transforms to the {alpha} phase after the crystallite size increases over a critical size during the calcination process at 1200 {sup o}C. The highest BET specific surface areas were obtained for both nitrate-aspartic acid routes proposed in this work, reaching values of about 50 m{sup 2}/g.

  20. Pheromone Static Routing Strategy for Complex Networks

    Science.gov (United States)

    Hu, Mao-Bin; Henry, Y. K. Lau; Ling, Xiang; Jiang, Rui

    2012-12-01

    We adopt the concept of using pheromones to generate a set of static paths that can reach the performance of global dynamic routing strategy [Phys. Rev. E 81 (2010) 016113]. The path generation method consists of two stages. In the first stage, a pheromone is dropped to the nodes by packets forwarded according to the global dynamic routing strategy. In the second stage, pheromone static paths are generated according to the pheromone density. The output paths can greatly improve traffic systems' overall capacity on different network structures, including scale-free networks, small-world networks and random graphs. Because the paths are static, the system needs much less computational resources than the global dynamic routing strategy.