WorldWideScience

Sample records for assisted reaction route

  1. 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

  2. Microwave- assisted solvent-free Diels-Alder reaction – a fast and simple route to various 5,6-substituted norbornenes and polychlorinated norbornenes

    Czech Academy of Sciences Publication Activity Database

    Dejmek, Milan; Hřebabecký, Hubert; Šála, Michal; Dračínský, Martin; Nencka, Radim

    -, č. 24 (2011), s. 4077-4083 ISSN 0039-7881 R&D Projects: GA MŠk 1M0508 Institutional research plan: CEZ:AV0Z40550506 Keywords : Diels - Alder reaction * polychlorinated norbornanes * norbornene Subject RIV: CC - Organic Chemistry Impact factor: 2.466, year: 2011

  3. Nanocrystalline spinel ferrites by solid state reaction route

    Indian Academy of Sciences (India)

    Wintec

    Nanocrystalline spinel ferrites by solid state reaction route. T K KUNDU* and S MISHRA. Department of Physics, Visva-Bharati, Santiniketan 731 235, India. Abstract. Nanostructured NiFe2O4, MnFe2O4 and (NiZn)Fe2O4 were synthesized by aliovalent ion doping using conventional solid-state reaction route. With the ...

  4. Computer-Assisted Periodical Routing and Renewal Audit

    Science.gov (United States)

    Yerkey, A. Neil

    1973-01-01

    A computer-assisted periodical control system was designed to reduce clerical time required to maintain records in three areas: renewal audit, routing, and records-keeping. The renewal audit features are unusual and are described in detail. (3 references) (Author/DH)

  5. Alternative reaction routes during coal hydrogenation and coal derived oil upgrading

    Energy Technology Data Exchange (ETDEWEB)

    Schulz, H.; Kordokuzis, G.; Langner, M. (University of Karlsruhe, Karlsruhe (Germany, F.R.). Engler-Bunte-Institute)

    1989-10-01

    Alternative reaction routes have been traced for the hydrodenitrogenation and hydrodeoxygenation of coal structure related model compounds. Reaction pathways are very structure specific. It is shown how reaction mechanisms switch from one route to another with changes in reaction conditions and catalyst features. Optimization of coal liquefaction processes can make use of this detailed understanding of selectivity. 5 refs., 7 figs.

  6. Mobility-Assisted on-Demand Routing Algorithm for MANETs in the Presence of Location Errors

    Directory of Open Access Journals (Sweden)

    Trung Kien Vu

    2014-01-01

    Full Text Available We propose a mobility-assisted on-demand routing algorithm for mobile ad hoc networks in the presence of location errors. Location awareness enables mobile nodes to predict their mobility and enhances routing performance by estimating link duration and selecting reliable routes. However, measured locations intrinsically include errors in measurement. Such errors degrade mobility prediction and have been ignored in previous work. To mitigate the impact of location errors on routing, we propose an on-demand routing algorithm taking into account location errors. To that end, we adopt the Kalman filter to estimate accurate locations and consider route confidence in discovering routes. Via simulations, we compare our algorithm and previous algorithms in various environments. Our proposed mobility prediction is robust to the location errors.

  7. 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.

  8. Multicomponent reactions: A simple and efficient route to heterocyclic phosphonates

    Science.gov (United States)

    2016-01-01

    Summary Multicomponent reactions (MCRs) are one of the most important processes for the preparation of highly functionalized organic compounds in modern synthetic chemistry. As shown in this review, they play an important role in organophosphorus chemistry where phosphorus reagents are used as substrates for the synthesis of a wide range of phosphorylated heterocycles. In this article, an overview about multicomponent reactions used for the synthesis of heterocyclic compounds bearing a phosphonate group on the ring is given. PMID:27559377

  9. Polymer-assisted co-precipitation route for the synthesis of Al 2 O 3

    Indian Academy of Sciences (India)

    It has been observed by field emission scanning electron microscopy analysis that the particle size reduced effectively (below 100 nm) when polymer-assisted co-precipitation route is used instead of the simple co-precipitation technique. A highly dense microstructure of sintered samples has been obtained, driven by ...

  10. Nanostructured palladium tailored via carbonyl chemical route towards oxygen reduction reaction

    International Nuclear Information System (INIS)

    Luo, Y.; Mora-Hernández, J.M.; Estudillo-Wong, L.A.; Arce-Estrada, E.M.; Alonso-Vante, N.

    2015-01-01

    Graphical Abstract: Mass-depending morphologies of nanostructured Palladium obtained via the carbonyl chemical route. Display Omitted -- Highlights: •Mass-depending morphology was observed in nanostructured palladium supported on carbon prepared by the carbonyl chemical route. •The Morphological effect of carbon supported Pd was investigated towards ORR. -- Abstract: Carbon supported palladium nanostructures were synthesized via the carbonyl chemical route. Compared with nanostructured platinum, prepared via carbonyl chemical route, Pd nanomaterials showed mass-loading morphology, whereas particle size and morphology of Pt nanostructures was constant. The oxygen reduction reaction (ORR) on nanostructured Pd, with different morphology in both acid and alkaline medium was investigated. A relationship, based on X-ray diffraction structural analysis pattern, transmission electron microscope, with the Pd morphological effect on ORR activity was identified

  11. The exothermic reaction route of a self-heatable conductive ink for rapid processable printed electronics.

    Science.gov (United States)

    Shin, Dong-Youn; Han, Jin Wook; Chun, Sangki

    2014-01-07

    We report the exothermic reaction route and new capability of a self-heatable conductive ink (Ag2O and silver 2,2-dimethyloctanoate) in order to achieve both a low sintering temperature and electrical resistivity within a short sintering time for flexible printed electronics and display appliances. Unlike conventional conductive ink, which requires a costly external heating instrument for rapid sintering, self-heatable conductive ink by itself is capable of generating heat as high as 312 °C when its exothermic reaction is triggered at a temperature of 180 °C. This intensive exothermic reaction is found to result from the recursive reaction of the 2,2-dimethyloctanoate anion, which is thermally dissociated from silver 2,2-dimethyloctanoate, with silver oxide microparticles. Through this recursive reaction, a massive number of silver atoms are supplied from silver oxide microparticles, and the nucleation of silver atoms and the fusion of silver nanoparticles become the major source of heat. This exothermic reaction eventually realizes the electrical resistivity of self-heatable conductive ink as low as 27.5 μΩ cm within just 40 s by combining chemical annealing, which makes it suitable for the roll-to-roll printable electronics such as a flexible touch screen panel.

  12. Influence of interface reactions on the YBCO films grown by fluorine-free solution route

    DEFF Research Database (Denmark)

    Zhao, Yue; Wu, Wei; Tang, Xiao

    2015-01-01

    Fabrication of full-stacked coated conductors by all-chemical-solution routes exhibit a great potential in view of further reducing the cost and increasing the throughput for industrialization. Growth of YBa2Cu3O7−x (YBCO) superconducting films by fluorine-free metal organic deposition routes (FF......-MOD) which are environmental friendly has attracted more attentions recently. In this work, comparison study was performed on the YBCO-Ag superconducting thin films deposited on two types of single crystal substrates, LaAlO3 and Ce0.9La0.9O2−y/YSZ. The structural characterization and superconducting...... properties studies reveal that the interface reactions between the YBCO-Ag film and the CLO cap layer play an essential role on the nucleation and growth of YBCO-Ag films from the FF solution. Weak texture caused by serious interface reactions at high growth temperature is the main explanations for the poor...

  13. The exothermic reaction route of a self-heatable conductive ink for rapid processable printed electronics

    Science.gov (United States)

    Shin, Dong-Youn; Han, Jin Wook; Chun, Sangki

    2013-12-01

    We report the exothermic reaction route and new capability of a self-heatable conductive ink (Ag2O and silver 2,2-dimethyloctanoate) in order to achieve both a low sintering temperature and electrical resistivity within a short sintering time for flexible printed electronics and display appliances. Unlike conventional conductive ink, which requires a costly external heating instrument for rapid sintering, self-heatable conductive ink by itself is capable of generating heat as high as 312 °C when its exothermic reaction is triggered at a temperature of 180 °C. This intensive exothermic reaction is found to result from the recursive reaction of the 2,2-dimethyloctanoate anion, which is thermally dissociated from silver 2,2-dimethyloctanoate, with silver oxide microparticles. Through this recursive reaction, a massive number of silver atoms are supplied from silver oxide microparticles, and the nucleation of silver atoms and the fusion of silver nanoparticles become the major source of heat. This exothermic reaction eventually realizes the electrical resistivity of self-heatable conductive ink as low as 27.5 μΩ cm within just 40 s by combining chemical annealing, which makes it suitable for the roll-to-roll printable electronics such as a flexible touch screen panel.We report the exothermic reaction route and new capability of a self-heatable conductive ink (Ag2O and silver 2,2-dimethyloctanoate) in order to achieve both a low sintering temperature and electrical resistivity within a short sintering time for flexible printed electronics and display appliances. Unlike conventional conductive ink, which requires a costly external heating instrument for rapid sintering, self-heatable conductive ink by itself is capable of generating heat as high as 312 °C when its exothermic reaction is triggered at a temperature of 180 °C. This intensive exothermic reaction is found to result from the recursive reaction of the 2,2-dimethyloctanoate anion, which is thermally

  14. Mobile Sinks Assisted Geographic and Opportunistic Routing Based Interference Avoidance for Underwater Wireless Sensor Network.

    Science.gov (United States)

    Ahmed, Farwa; Wadud, Zahid; Javaid, Nadeem; Alrajeh, Nabil; Alabed, Mohamad Souheil; Qasim, Umar

    2018-04-02

    The distinctive features of acoustic communication channel-like high propagation delay, multi-path fading, quick attenuation of acoustic signal, etc. limit the utilization of underwater wireless sensor networks (UWSNs). The immutable selection of forwarder node leads to dramatic death of node resulting in imbalanced energy depletion and void hole creation. To reduce the probability of void occurrence and imbalance energy dissipation, in this paper, we propose mobility assisted geo-opportunistic routing paradigm based on interference avoidance for UWSNs. The network volume is divided into logical small cubes to reduce the interference and to make more informed routing decisions for efficient energy consumption. Additionally, an optimal number of forwarder nodes is elected from each cube based on its proximity with respect to the destination to avoid void occurrence. Moreover, the data packets are recovered from void regions with the help of mobile sinks which also reduce the data traffic on intermediate nodes. Extensive simulations are performed to verify that our proposed work maximizes the network lifetime and packet delivery ratio.

  15. Mobile Sinks Assisted Geographic and Opportunistic Routing Based Interference Avoidance for Underwater Wireless Sensor Network

    Directory of Open Access Journals (Sweden)

    Farwa Ahmed

    2018-04-01

    Full Text Available The distinctive features of acoustic communication channel-like high propagation delay, multi-path fading, quick attenuation of acoustic signal, etc. limit the utilization of underwater wireless sensor networks (UWSNs. The immutable selection of forwarder node leads to dramatic death of node resulting in imbalanced energy depletion and void hole creation. To reduce the probability of void occurrence and imbalance energy dissipation, in this paper, we propose mobility assisted geo-opportunistic routing paradigm based on interference avoidance for UWSNs. The network volume is divided into logical small cubes to reduce the interference and to make more informed routing decisions for efficient energy consumption. Additionally, an optimal number of forwarder nodes is elected from each cube based on its proximity with respect to the destination to avoid void occurrence. Moreover, the data packets are recovered from void regions with the help of mobile sinks which also reduce the data traffic on intermediate nodes. Extensive simulations are performed to verify that our proposed work maximizes the network lifetime and packet delivery ratio.

  16. Gas-Solid Reaction Route toward the Production of Intermetallics from Their Corresponding Oxide Mixtures

    Directory of Open Access Journals (Sweden)

    Hesham Ahmed

    2016-08-01

    Full Text Available Near-net shape forming of metallic components from metallic powders produced in situ from reduction of corresponding pure metal oxides has not been explored to a large extent. Such a process can be probably termed in short as the “Reduction-Sintering” process. This methodology can be especially effective in producing components containing refractory metals. Additionally, in situ production of metallic powder from complex oxides containing more than one metallic element may result in in situ alloying during reduction, possibly at lower temperatures. With this motivation, in situ reduction of complex oxides mixtures containing more than one metallic element has been investigated intensively over a period of years in the department of materials science, KTH, Sweden. This review highlights the most important features of that investigation. The investigation includes not only synthesis of intermetallics and refractory metals using the gas solid reaction route but also study the reaction kinetics and mechanism. Environmentally friendly gases like H2, CH4 and N2 were used for simultaneous reduction, carburization and nitridation, respectively. Different techniques have been utilized. A thermogravimetric analyzer was used to accurately control the process conditions and obtain reaction kinetics. The fluidized bed technique has been utilized to study the possibility of bulk production of intermetallics compared to milligrams in TGA. Carburization and nitridation of nascent formed intermetallics were successfully carried out. A novel method based on material thermal property was explored to track the reaction progress and estimate the reaction kinetics. This method implies the dynamic measure of thermal diffusivity using laser flash method. These efforts end up with a successful preparation of nanograined intermetallics like Fe-Mo and Ni-W. In addition, it ends up with simultaneous reduction and synthesis of Ni-WN and Ni-WC from their oxide mixtures

  17. Synthesis of flower-like Boehmite (γ-AlOOH) via a one-step ionic liquid-assisted hydrothermal route

    International Nuclear Information System (INIS)

    Tang, Zhe; Liang, Jilei; Li, Xuehui; Li, Jingfeng; Guo, Hailing; Liu, Yunqi; Liu, Chenguang

    2013-01-01

    A simple and novel synthesis process, one-step ionic liquid-assisted hydrothermal synthesis route, has been developed in the work to synthesize Bohemithe (γ-AlOOH) with flower-like structure. The samples were characterized by X-ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FT-IR) and Scanning Electron Microscope (SEM). Ionic liquid [Omim] + Cl − , as a template, plays an important role in the morphology and pore structure of the products due to its strong interactions with reaction particles. With the increase in the dosage of ionic liquid [Omim] + Cl − , the morphology of the γ-AlOOH was changed from initial bundles of nanosheets (without ionic liquid) into final well-developed monodispersed 3D flower-like architectures ([Omim] + Cl − =72 mmol). The pore structure was also altered gradually from initial disordered slit-like pore into final relatively ordered ink-bottle pore. Furthermore, the proposed formation mechanism and other influencing factors such as reaction temperature and urea on formation and morphology of the γ-AlOOH have also been investigated. - Graphical abstract: The flower-like γ-AlOOH architectures composed by nanosheets with narrow size distribution (1.6–2.2 μm) and uniform pore size (6.92 nm) have been synthesized via a one-step ionic liquid-assisted hydrothermal route. - Highlights: • The γ-AlOOH microflowers were synthesized via an ionic liquid-assisted hydrothermal route. • Ionic liquid plays an important role on the morphology and porous structure of the products. • Ionic liquid can be easily removed from the products and reused in recycling experiments. • A “aggregation–recrystallization–Ostwald Ripening“formation mechanism may occur

  18. Ion-assisted phase separation in compound films: An alternate route to ordered nanostructures

    International Nuclear Information System (INIS)

    Norris, Scott A.

    2013-01-01

    In recent years, observations of highly ordered, hexagonal arrays of self-organized nanostructures on binary or impurity-laced targets under normal-incidence ion irradiation have excited interest in this phenomenon as a potential route to high-throughput, low-cost manufacture of nanoscale devices or nanostructured coatings. The currently prominent explanation for these structures is a morphological instability driven by ion erosion discovered by Bradley and Shipman; however, recent parameter estimates via molecular dynamics simulations suggest that this erosive instability may not be active for the representative GaSb system in which hexagonal structures were first observed. Motivated by recent experimental and numerical evidence suggesting the likely importance of phase separation during thin-film processing, we here generalize the Bradley-Shipman theory to include the effect of ion-assisted phase separation. The resulting system admits a chemically driven finite-wavelength instability that can explain the order of observed patterns even when the erosive Bradley-Shipman instability is inactive. In a relevant simplifying limit, it also provides an intuitive instability criterion similar to results in thin-film deposition, as well as predictions on pattern wavelengths that agree qualitatively with experimental observations. Finally, we identify a characteristic experimental signature that distinguishes the chemical and morphological instabilities and highlights the need for specific additional experimental data on the GaSb system

  19. Multiscale Reaction-Diffusion Algorithms: PDE-Assisted Brownian Dynamics

    KAUST Repository

    Franz, Benjamin

    2013-06-19

    Two algorithms that combine Brownian dynami cs (BD) simulations with mean-field partial differential equations (PDEs) are presented. This PDE-assisted Brownian dynamics (PBD) methodology provides exact particle tracking data in parts of the domain, whilst making use of a mean-field reaction-diffusion PDE description elsewhere. The first PBD algorithm couples BD simulations with PDEs by randomly creating new particles close to the interface, which partitions the domain, and by reincorporating particles into the continuum PDE-description when they cross the interface. The second PBD algorithm introduces an overlap region, where both descriptions exist in parallel. It is shown that the overlap region is required to accurately compute variances using PBD simulations. Advantages of both PBD approaches are discussed and illustrative numerical examples are presented. © 2013 Society for Industrial and Applied Mathematics.

  20. Reaction of Acetylenedicarboxylic Acid Made Easy: High-Pressure Route for Polymerization

    DEFF Research Database (Denmark)

    Delori, Amit; Hutchison, Ian B.; Bull, Craig L.

    2018-01-01

    A breakthrough has been achieved in improving the efficiency of solid-state polymerization of acetylenedicarboxylic acid (ADCA). Traditional solid-state polymerization of ADCA is marked by long exposure times of γ-radiation (>10 days) and very low yields (around 5.5%). We have been able to perform...... a reaction to an n = 8 oligomer, as confirmed by matrix-assisted laser desorption/ionization-time of flight, in less than 2 min by employing ∼6 GPa of pressure. We have determined the crystal structure of ADCA on increasing pressure to (5.2 GPa) to provide insight into the process of polymerization...... with Pixel calculations supporting our evaluation of the polymerization process....

  1. Evaluation of Opportunistic Routing Algorithms on Opportunistic Mobile Sensor Networks with Infrastructure Assistance

    NARCIS (Netherlands)

    Le Viet Duc, L Duc; Scholten, Johan; Havinga, Paul J.M.

    2012-01-01

    Recently the increasing number of sensors integrated in smartphones, especially the iPhone and Android phones, has motivated the development of routing algorithms for Opportunistic Mobile Sensor Networks (OppMSNs). Although there are many existing opportunistic routing algorithms, researchers still

  2. Energy Considerations for Plasma-Assisted N-Fixation Reactions

    Directory of Open Access Journals (Sweden)

    Aikaterini Anastasopoulou

    2014-09-01

    Full Text Available In a time of increasing concerns about the immense energy consumption and poor environmental performance of contemporary processes in the chemical industry, there is great need to develop novel sustainable technologies that enhance energy efficiency. There is abundant chemical literature on process innovations (laboratory-scale around the plasma reactor itself, which, naturally, is the essential part to be intensified to achieve a satisfactory process. In essence, a plasma process needs attention beyond reaction engineering towards the process integration side and also with strong electrical engineering focus. In this mini-review, we have detailed our future focus on the process and energy intensification of plasma-based N-fixation. Three focal points are mainly stressed throughout the review: (I the integration of renewable energy; (II the power supply system of plasma reactors and (III process design of industrial plasma-assisted nitrogen fixation. These different enabling strategies will be set in a holistic and synergetic picture so as to improve process performance.

  3. 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.

  4. A facile strategy for the fabrication of uniform CdS nanowires with high yield and its controlled morphological growth with the assistance of PEG in hydrothermal route

    International Nuclear Information System (INIS)

    Pal, Kaushik; Maiti, Uday Narayan; Majumder, Tapas Pal; Debnath, Subhas Chandra

    2011-01-01

    A series of novel wurtzite cadmium sulphide (CdS) nanowires with uniform diameter were synthesized by using a rapid and simple solvothermal route. CdS nano structures with certain morphology could be selectively produced by only varying the concentration of poly ethylene glycol (PEG) as a surfactant in the reaction system with cadmium acetate, sulphur powder and ethelynediamine (EDA). We extensively studied UV-vis absorption spectra, photoluminescence spectra after confirming CdS nanowires with diameter 24-25 nm and length ranging up to several nano meters by field emission scanning electron microscopy (FE-SEM). Therefore we may definitely propose a new formation mechanism of CdS nanowires assisted by PEG with its illustrating optical properties.

  5. A novel tandem Betti/Ullmann oxidation reaction as an efficient route ...

    Indian Academy of Sciences (India)

    Betti reaction; cross-coupling reaction; oxidation; heterogeneous catalysis. Abstract. A novel tandem Betti/Ullmann/oxidation reaction was used for synthesis of new oxazepine derivatives containing kojic acid. This protocol ... This method provides a new and useful strategy for the construction of heterocycles. Also novel Betti ...

  6. Computer-assisted mechanistic evaluation of organic reactions

    Energy Technology Data Exchange (ETDEWEB)

    Gushurst, A.J.

    1988-01-01

    CAMEO, an interactive computer program which predicts the products of organic reactions given starting materials and conditions, has been refined and extended in the area of base-catalyzed and nucleophilic processes. The present capabilities of the program are outlined including brief discussion on the major segments in CAMEO: graphics, perception, and reaction evaluation. The implementation of general algorithms for predicting the acidities of a vast number of organic compounds to within 2 pK{sub a} units in dimethylsulfoxide and water are then described, followed by a presentation of the reactivity rules used by the program to evaluate nucleophilc reactions. Finally, a treatment of sulfur and phosphorus ylides, iminophosphoranes, and P=X-activated anions is given illuminating the various competitions available for these reagents, such as between proton transfer and addition, 1,2- and 1,4-addition, and the Peterson, Wittig, and Horner-Emmons olefination reactions.

  7. Computer aided design, analysis and experimental investigation of membrane assisted batch reaction-separation systems

    DEFF Research Database (Denmark)

    Mitkowski, Piotr Tomasz; Buchaly, Carsten; Kreis, Peter

    2009-01-01

    Membrane assisted batch reaction operation offers an interesting option for equilibrium limited reaction systems in chemical and biochemical manufacturing by selective removal of one of the products and thereby increasing the product yield. The design of such hybrid systems need to take into acco......Membrane assisted batch reaction operation offers an interesting option for equilibrium limited reaction systems in chemical and biochemical manufacturing by selective removal of one of the products and thereby increasing the product yield. The design of such hybrid systems need to take...... into account the performance of each constituent element and the optimisation of the design must take into consideration their interdependency. In this paper use of a membrane, to assist in the synthesis of propyl-propionate is investigated through the use of a hybrid process design framework, which consists...... and separation functionalities and to design/analyse the hybrid scheme. The generated hybrid scheme has been validated through experiments involving an esterification reaction....

  8. Microwave-Assisted Synthesis of 5-Phenyl-2-Hydroxyacetophenone Derivatives by a Green Suzuki Coupling Reaction

    Science.gov (United States)

    Soares, Pedro; Fernandes, Carlos; Chavarria, Daniel; Borges, Fernanda

    2015-01-01

    In recent years, the use of boron-containing reagents in palladium-assisted C-C coupling reactions (the Suzuki reaction) has gained prominence due to the vast array of reagents commercially available. Consequently, the generation of carbon-carbon bonds, namely of functionalized biphenyl systems, is at present considered the backbone of organic…

  9. Synthesis of single-crystal perovskite PbCrO3 through a new reaction route at high pressure

    Science.gov (United States)

    Han, Yunxia; Wang, Shanmin; Liu, Yinjuan; Ma, Dejiang; He, Duanwei; Zhao, Yusheng

    2018-04-01

    As a new member in the family of Mott system, perovskite PbCrO3 has recently been uncovered to exhibit fantastic structural transition under pressure, coupled with magnetic, electronic, and ferromagnetic transitions, which provide many opportunities for understanding of correlated system. However, it is still challenging to synthesize high-quality single-crystal PbCrO3, leading to the limited exploration of this Mott compound. In this work, we formulate a new high-pressure reaction route for preparation of high-quality PbCrO3 crystals between PbCl2 and Na2CrO4 at high pressure of 5-10 GPa and at high temperature of 750-1500°C. Because of the formation of reaction byproduct NaCl, the final product can readily be separated by washing with water. The obtained sample is in the form of single crystal with crystallite size up to 200 μm. In addition, combined with X-ray diffraction measurement, a tentative pressure-temperature synthesis diagram of PbCrO3 is mapped out from the reaction between PbCl2 and Na2CrO4 and the reaction mechanism is also explored in detail.

  10. Minimalistic Liquid-Assisted Route to Highly Crystalline α-Zirconium Phosphate.

    Science.gov (United States)

    Cheng, Yu; Wang, Xiaodong Tony; Jaenicke, Stephan; Chuah, Gaik-Khuan

    2017-08-24

    Zirconium phosphates have potential applications in areas of ion exchange, catalysis, photochemistry, and biotechnology. However, synthesis methodologies to form crystalline α-zirconium phosphate (Zr(HPO 4 ) 2 ⋅H 2 O) typically involve the use of excess phosphoric acid, addition of HF or oxalic acid and long reflux times or hydrothermal conditions. A minimalistic sustainable route to its synthesis has been developed by using only zirconium oxychloride and concentrated phosphoric acid to form highly crystalline α-zirconium phosphate within hours. The morphology can be changed from platelets to rod-shaped particles by fluoride addition. By varying the temperature and time, α-zirconium phosphate with particle sizes from nanometers to microns can be obtained. Key features of this minimal solvent synthesis are the excellent yields obtained with high atom economy under mild conditions and ease of scalability. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. ZrTiO4 nanowire growth using membrane-assisted Pechini route

    Directory of Open Access Journals (Sweden)

    P. R. de Lucena

    2014-11-01

    Full Text Available The high surface-to-volume ratio of nanowires makes them natural competitors as new device components. In this regard, a current major challenge is to produce quasi-one-dimensional nanostructures composed of well established oxide-based materials. This article reports the synthesis of ZrTiO4 nanowires on a silicon (100 wafer in a single-step deposition/thermal treatment. The template-directed membrane synthesis strategy was associated with the Pechini route and spin-coating deposition technique. ZrTiO4 nanowires were obtained at 700 ˚C with diameters in the range of 80-100 nm. FEG- SEM images were obtained to investigate ZrTiO4 nanowire formation on the silicon surface and energy dispersive x-ray detection (EDS and x-ray diffraction (XRD analyses were performed to confirm the oxide composition and structure.

  12. ZrTiO4 Nanowire Growth Using Membrane-assisted Pechini Route

    Directory of Open Access Journals (Sweden)

    Poty Rodrigues de Lucena

    2016-02-01

    Full Text Available The high surface-to-volume ratio of nanowires makes them natural competitors as newer device components. In this regard, a current major challenge is to produce quasi-one-dimensional nanostructures composed of well-established oxide-based materials. This article reports the synthesis of ZrTiO4 nanowires on a silicon (100 wafer in a single-step deposition/thermal treatment. The template-directed membrane synthesis strategy was associated with the Pechini route and spin-coating deposition technique. ZrTiO4 nanowires were obtained at 700 °C with diameters in the range of 80-100 nm. FEGSEM images were obtained to investigate ZrTiO4 nanowire formation on the silicon surface and energy dispersive X-ray detection (EDS and X-ray diffraction (XRD analyses were performed to confirm the oxide composition and structure. 

  13. Secondary Interactions Arrest the Hemiaminal Intermediate To Invert the Modus Operandi of Schiff Base Reaction: A Route to Benzoxazinones.

    Science.gov (United States)

    Patel, Ketan; Deshmukh, Satej S; Bodkhe, Dnyaneshwar; Mane, Manoj; Vanka, Kumar; Shinde, Dinesh; Rajamohanan, Pattuparambil R; Nandi, Shyamapada; Vaidhyanathan, Ramanathan; Chikkali, Samir H

    2017-04-21

    Discovered by Hugo Schiff, condensation between amine and aldehyde represents one of the most ubiquitous reactions in chemistry. This classical reaction is widely used to manufacture pharmaceuticals and fine chemicals. However, the rapid and reversible formation of Schiff base prohibits formation of alternative products, of which benzoxazinones are an important class. Therefore, manipulating the reactivity of two partners to invert the course of this reaction is an elusive target. Presented here is a synthetic strategy that regulates the sequence of Schiff base reaction via weak secondary interactions. Guided by the computational models, reaction between 2,3,4,5,6-pentafluoro-benzaldehyde with 2-amino-6-methylbenzoic acid revealed quantitative (99%) formation of 5-methyl-2-(perfluorophenyl)-1,2-dihydro-4H-benzo[d][1,3]oxazin-4-one (15). Electron donating and electron withdrawing ortho-substituents on 2-aminobenzoic acid resulted in the production of benzoxazinones 9-36. The mode of action was tracked using low temperature NMR, UV-vis spectroscopy, and isotopic ( 18 O) labeling experiments. These spectroscopic mechanistic investigations revealed that the hemiaminal intermediate is arrested by the hydrogen-bonding motif to yield benzoxazinone. Thus, the mechanistic investigations and DFT calculations categorically rule out the possibility of in situ imine formation followed by ring-closing, but support instead hydrogen-bond assisted ring-closing to prodrugs. This unprecedented reaction represents an interesting and competitive alternative to metal catalyzed and classical methods of preparing benzoxazinone.

  14. Hydrogen-Assisted IC Engine Combustion as a Route to Hydrogen Implementation

    Energy Technology Data Exchange (ETDEWEB)

    Andre Boehman; Daniel Haworth

    2008-09-30

    The 'Freedom Car' Initiative announced by the Bush Administration has placed a significant emphasis on development of a hydrogen economy in the United States. While the hydrogen-fueled fuel-cell vehicle that is the focus of the 'Freedom Car' program would rely on electrochemical energy conversion, and despite the large amount of resources being devoted to its objectives, near-term implementation of hydrogen in the transportation sector is not likely to arise from fuel cell cars. Instead, fuel blending and ''hydrogen-assisted'' combustion are more realizable pathways for wide-scale hydrogen utilization within the next ten years. Thus, a large potential avenue for utilization of hydrogen in transportation applications is through blending with natural gas, since there is an existing market for natural-gas vehicles of various classes, and since hydrogen can provide a means of achieving even stricter emissions standards. Another potential avenue is through use of hydrogen to 'assist' diesel combustion to permit alternate combustion strategies that can achieve lower emissions and higher efficiency. This project focused on developing the underlying fundamental information to support technologies that will facilitate the introduction of coal-derived hydrogen into the market. Two paths were envisioned for hydrogen utilization in transportation applications. One is for hydrogen to be mixed with other fuels, specifically natural gas, to enhance performance in existing natural gas-fueled vehicles (e.g., transit buses) and provide a practical and marketable avenue to begin using hydrogen in the field. A second is to use hydrogen to enable alternative combustion modes in existing diesel engines, such as homogeneous charge compression ignition, to permit enhanced efficiency and reduced emissions. Thus, this project on hydrogen-assisted combustion encompassed two major objectives: (1) Optimization of hydrogen-natural gas mixture

  15. Microwave-assisted routes for rapid and efficient modification of layered perovskites.

    Science.gov (United States)

    Akbarian-Tefaghi, S; Wiley, J B

    2018-02-27

    Recent advances in exploiting microwave radiation in the topochemical modification of layered oxide perovskites are presented. Such methods work well for rapid bulk synthetic steps used in the production of novel inorganic-organic hybrids (protonation, grafting, intercalation, and in situ click reactions), exfoliation to produce dispersed nanosheets, and post-exfoliation processing to rapidly vary nanosheet surface groups. Compared to traditional methods that often take days, microwave methods can produce quality products in as little as 1-2 h.

  16. Machine assisted reaction optimization: A self-optimizing reactor system for continuous-flow photochemical reactions

    KAUST Repository

    Poscharny, K.; Fabry, D.C.; Heddrich, S.; Sugiono, E.; Liauw, M.A.; Rueping, Magnus

    2018-01-01

    A methodology for the synthesis of oxetanes from benzophenone and furan derivatives is presented. UV-light irradiation in batch and flow systems allowed the [2 + 2] cycloaddition reaction to proceed and a broad range of oxetanes could be synthesized in manual and automated fashion. The identification of high-yielding reaction parameters was achieved through a new self-optimizing photoreactor system.

  17. Machine assisted reaction optimization: A self-optimizing reactor system for continuous-flow photochemical reactions

    KAUST Repository

    Poscharny, K.

    2018-04-07

    A methodology for the synthesis of oxetanes from benzophenone and furan derivatives is presented. UV-light irradiation in batch and flow systems allowed the [2 + 2] cycloaddition reaction to proceed and a broad range of oxetanes could be synthesized in manual and automated fashion. The identification of high-yielding reaction parameters was achieved through a new self-optimizing photoreactor system.

  18. A Review of Microwave-Assisted Reactions for Biodiesel Production

    Directory of Open Access Journals (Sweden)

    Saifuddin Nomanbhay

    2017-06-01

    Full Text Available The conversion of biomass into chemicals and biofuels is an active research area as trends move to replace fossil fuels with renewable resources due to society’s increased concern towards sustainability. In this context, microwave processing has emerged as a tool in organic synthesis and plays an important role in developing a more sustainable world. Integration of processing methods with microwave irradiation has resulted in a great reduction in the time required for many processes, while the reaction efficiencies have been increased markedly. Microwave processing produces a higher yield with a cleaner profile in comparison to other methods. The microwave processing is reported to be a better heating method than the conventional methods due to its unique thermal and non-thermal effects. This paper provides an insight into the theoretical aspects of microwave irradiation practices and highlights the importance of microwave processing. The potential of the microwave technology to accomplish superior outcomes over the conventional methods in biodiesel production is presented. A green process for biodiesel production using a non-catalytic method is still new and very costly because of the supercritical condition requirement. Hence, non-catalytic biodiesel conversion under ambient pressure using microwave technology must be developed, as the energy utilization for microwave-based biodiesel synthesis is reported to be lower and cost-effective.

  19. Synthesis of nano-sized hydroxyapatite powders through solution combustion route under different reaction conditions

    International Nuclear Information System (INIS)

    Ghosh, Samir Kumar; Roy, Sujit Kumar; Kundu, Biswanath; Datta, Someswar; Basu, Debabrata

    2011-01-01

    Calcium hydroxyapatite, Ca 10 (PO 4 ) 6 (OH) 2 (HAp) was synthesized by combustion in the aqueous system containing calcium nitrate-diammonium hydrogen orthophosphate with urea and glycine as fuels. These ceramics are important materials for biomedical applications. Thermo-gravimetric and differential thermal analysis were employed to understand the nature of synthesis process during combustion. Effects of different process parameters namely, nature of fuel (urea and glycine), fuel to oxidizer ratio (0.6-4.0) and initial furnace temperature (300-700 o C) on the combustion behavior as well as physical properties of as-formed powders were investigated. A series of combustion reactions were carried out to optimize the reaction parameters for synthesis of nano-sized HAp powders. The combustion temperature (T f ) for the oxidant and fuels were calculated to be 896 deg. C and 1035 deg. C for the stoichiometric system of urea and glycine respectively. The stoichiometric glycine-calcium nitrate produced higher flame temperature (both calculated and measured) and powder with lower specific surface area (8.75 m 2 /g) compared to the stoichiometric urea-calcium nitrate system (10.50 m 2 /g). Fuel excess combustion in both glycine and urea produced powders with higher surface area. Nanocrystalline HAp powder could be synthesized in situ with a large span of fuel to oxidizer ratio (φ) in case of urea system (0.8 < φ < 4) and (0.6 < φ < 1.5) for the glycine system. Calcium hydroxyapatite particles having diameters ranging between 20 nm and 120 nm could be successfully synthesized through optimized process variable.

  20. CO gas sensing of CuO nanostructures, synthesized by an assisted solvothermal wet chemical route

    International Nuclear Information System (INIS)

    Aslani, Alireza; Oroojpour, Vahid

    2011-01-01

    CuO nanostructures with different morphologies and sizes were grown in a controlled manner using a simple low-temperature hydrothermal technique. By controlling the pH of reaction mixture, spherical nanoparticles and cloudlike CuO structures were synthesized at 100-150 o C with excellent efficiency. These CuO nanostructures have been tested for CO gas monitoring by depositing them as thick films on an interdigitated alumina substrate and evaluated the surface resistance of the deposited layer as a function of operating temperature and CO concentrations. The gas sensitivity tests have demonstrated that the CuO nanostructures, especially cloudlike morphology, exhibit high sensitivity to CO proving their applicability in gas sensors. The role of the nanostructure on the sensing properties of CuO is also discussed.

  1. Cascades in Compartments: En Route to Machine-Assisted Biotechnology.

    Science.gov (United States)

    Rabe, Kersten S; Müller, Joachim; Skoupi, Marc; Niemeyer, Christof M

    2017-10-23

    Biological compartmentalization is a fundamental principle of life that allows cells to metabolize, propagate, or communicate with their environment. Much research is devoted to understanding this basic principle and to harness biomimetic compartments and catalytic cascades as tools for technological processes. This Review summarizes the current state-of-the-art of these developments, with a special emphasis on length scales, mass transport phenomena, and molecular scaffolding approaches, ranging from small cross-linkers over proteins and nucleic acids to colloids and patterned surfaces. We conclude that the future exploration and exploitation of these complex systems will largely benefit from technical solutions for the integrated, machine-assisted development and maintenance of a next generation of biotechnological processes. These goals should be achievable by implementing microfluidics, robotics, and added manufacturing techniques supplemented by theoretical simulations as well as computer-aided process modeling based on big data obtained from multiscale experimental analyses. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Particle size and shape modification of hydroxyapatite nanostructures synthesized via a complexing agent-assisted route

    International Nuclear Information System (INIS)

    Mohandes, Fatemeh; Salavati-Niasari, Masoud

    2014-01-01

    In this work, hydroxyapatite (HAP), Ca 10 (PO 4 ) 6 (OH) 2 , nanostructures including nanorods, nanobundles and nanoparticles have been prepared via a simple precipitation method. In the present method, Ca(NO 3 ) 2 ·4H 2 O and (NH 4 ) 2 HPO 4 were used as calcium and phosphorus precursors, respectively. Besides, the Schiff bases derived from 2-hydroxyacetophenone and different diamines were used as complexing agents for the in situ formation of Ca 2+ complexes. The formation mechanism of 0-D and 1-D nanostructures of HAP was also considered. When the complexing agents could coordinate to the Ca 2+ ions through N and O atoms to form the [CaN 2 O 2 ] 2+ complexes, HAP nanoparticles were generated. On the other hand, nanorods and nanobundles of HAP were obtained by forming the [CaN 2 ] 2+ as well as [CaO 2 ] 2+ complexes in the reaction solution. This work is the first successful synthesis of pure HAP nanostructures in the presence of Schiff bases instead of using the common surfactants. - Highlights: • HAP nanostructures have been prepared by a simple precipitation method. • To control shape and particle size of HAP, different Schiff bases were employed. • 0-D and 1-D HAP nanostructures have been formed by this method

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

    KAUST Repository

    Liang, Hanfeng; Alshareef, Husam N.

    2017-01-01

    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

  4. Morphogenesis and crystallization of ZnS microspheres by a soft template-assisted hydrothermal route: synthesis, growth mechanism, and oxygen sensitivity.

    Science.gov (United States)

    Yang, Liangbao; Han, Jun; Luo, Tao; Li, Minqiang; Huang, Jiarui; Meng, Fanli; Liu, Jinhuai

    2009-01-05

    Almost monodisperse ZnS microspheres have been synthesized on a large scale by a hydrothermal route, in which tungstosilicate acid (TSA) was used as a soft template. By controlling the reaction conditions, such as reaction temperature, pH value of the solutions, and the reaction medium, almost monodisperse microspheres can be synthesized. The structure of these microspheres is sensitive to the reaction conditions. The growth mechanism of these nearly monodisperse microspheres was examined. Oxygen sensing is realized from ZnS microspheres. The current through the ZnS microspheres under UV illumination increases as the oxygen concentration decreases.

  5. Real time monitoring of accelerated chemical reactions by ultrasonication-assisted spray ionization mass spectrometry.

    Science.gov (United States)

    Lin, Shu-Hsuan; Lo, Ta-Ju; Kuo, Fang-Yin; Chen, Yu-Chie

    2014-01-01

    Ultrasonication has been used to accelerate chemical reactions. It would be ideal if ultrasonication-assisted chemical reactions could be monitored by suitable detection tools such as mass spectrometry in real time. It would be helpful to clarify reaction intermediates/products and to have a better understanding of reaction mechanism. In this work, we developed a system for ultrasonication-assisted spray ionization mass spectrometry (UASI-MS) with an ~1.7 MHz ultrasonic transducer to monitor chemical reactions in real time. We demonstrated that simply depositing a sample solution on the MHz-based ultrasonic transducer, which was placed in front of the orifice of a mass spectrometer, the analyte signals can be readily detected by the mass spectrometer. Singly and multiply charged ions from small and large molecules, respectively, can be observed in the UASI mass spectra. Furthermore, the ultrasonic transducer used in the UASI setup accelerates the chemical reactions while being monitored via UASI-MS. The feasibility of using this approach for real-time acceleration/monitoring of chemical reactions was demonstrated. The reactions of Girard T reagent and hydroxylamine with steroids were used as the model reactions. Upon the deposition of reactant solutions on the ultrasonic transducer, the intermediate/product ions are readily generated and instantaneously monitored using MS within 1 s. Additionally, we also showed the possibility of using this reactive UASI-MS approach to assist the confirmation of trace steroids from complex urine samples by monitoring the generation of the product ions. Copyright © 2014 John Wiley & Sons, Ltd.

  6. Magnetic field assisted Fenton reactions for the enhanced degradation of methyl blue

    Institute of Scientific and Technical Information of China (English)

    Xiao Long Hao; Lu Yi Zou; Guang Sheng Zhang; Yi Bo Zhang

    2009-01-01

    Magnetic field was tentatively introduced into Fenton reactions system for the degradation and discoloration of methyl blue as the represent of organic chemical dye, which was a bio-refractory organic pollutant in industry wastewater. It was found that under optimal Fenton reaction conditions, with the assistant of magnetic field in Fenton reactions, the degradation rate of methyl blue, the decomposition rate of H2O2 and the conversion rate of Fe2+ were accelerated, the extent of them would be improved by the increase of magnetic field intensity. Meanwhile, the mineralization of methyl blue (CODcr) was improved by over 10% with magnetic fiold.

  7. Nanoparticle-assisted photo-Fenton reaction for photo-decomposition of humic acid

    Science.gov (United States)

    Banik, Jhuma; Basumallick, Srijita

    2017-11-01

    We report here the synthesis of CuO-doped ZnO composite nanomaterials (NMs) by chemical route and demonstrated for the first time that these NMs are efficient catalysts for H2O2-assisted photo-decomposition (photo-Fenton type catalyst) of humic acid, a natural pollutant of surface water by solar irradiation. This has been explained by faster electron transfer to OH radical at the p-n hetero-junction of this composite catalyst. Application of this composite catalyst in decomposing humus substances of local pond water by solar energy has been demonstrated.

  8. Microwave-Assisted Organic Synthesis and Transformations using Benign Reaction Media

    Science.gov (United States)

    The nonclassical heating technique using microwaves, termed as 'Bunsen burner of the 21st century, is rapidly becoming popular and is dramatically reducing the reaction times. The significant outcomes of microwave (MW)-assisted green chemistry endeavors are summarized that have r...

  9. Efficient and 'green' microwave-assisted synthesis of haloalkylphosphonates via the Michaelis-Arbuzov reaction

    Czech Academy of Sciences Publication Activity Database

    Jansa, Petr; Holý, Antonín; Dračínský, Martin; Baszczyňski, Ondřej; Česnek, Michal; Janeba, Zlatko

    2011-01-01

    Roč. 13, č. 4 (2011), s. 882-888 ISSN 1463-9262 R&D Projects: GA AV ČR KJB400550903; GA MŠk 1M0508 Institutional research plan: CEZ:AV0Z40550506 Keywords : microwave-assisted synthesis * haloalkylphosphonates * Michaelis-Arbuzov reaction Subject RIV: CC - Organic Chemistry Impact factor: 6.320, year: 2011

  10. Effect of reaction systems and surfactant additives on the morphology evolution of hydroxyapatite nanorods obtained via a hydrothermal route

    Energy Technology Data Exchange (ETDEWEB)

    Ma Tianyuan; Xia Zhiguo [School of Materials Sciences and Technology, China University of Geosciences, Beijing 100083 (China); Liao Libing, E-mail: lbliao@cugb.edu.cn [School of Materials Sciences and Technology, China University of Geosciences, Beijing 100083 (China)

    2011-02-15

    Well-dispersed hydroxyapatite (HA) nanorods with different morphologies were synthesized by a hydrothermal method in oleic acid, ethanol and water reaction system, and the surfactant assisted modifications effect was also comparatively studied. The structure and morphology of samples were characterized using X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy and transmission electron microscopy (TEM), respectively. The effect of reaction systems and surfactant additives on the morphology evolution of HA nanorods were discussed in detail. The results showed that the controlled experimental conditions in the systems, such as the content ratio of oleic acid/ethanol, pH value and the content ratio of Ca/P source had an significant effect on the morphology evolution of as-prepared HA nanorods. Further, the selected surfactant additives, such as cetyltriethylammnonium bromide (CTAB), sodium dodecyl sulfate (K12) also play an important role in the formation of the uniform morphology of HA nanorods. Some possible formation mechanisms of the HA nanorods in the present reaction systems is proposed.

  11. Structural analysis of fluorine-containing bioactive glass nanoparticles synthesized by sol-gel route assisted by ultrasound energy.

    Science.gov (United States)

    Lins, Carolina E C; Oliveira, Agda A R; Gonzalez, Ismael; Macedo, Waldemar A A; Pereira, Marivalda M

    2018-01-01

    In the last decades, studies about the specific effects of bioactive glass on remineralization of dentin were the focus of attention, due to their excellent regenerative properties in mineralized tissues. The incorporation of Fluorine in bioactive glass nanoparticles may result in the formation of fluorapatite (FAP), which is chemically more stable than hydroxyapatite or carbonated hydroxyapatite, and therefore is of interest for dental applications. The aim of this study was to synthesize and characterize a new system of Fluorine-containing bioactive glass nanoparticles (BGNPF). A sol-gel route assisted by ultrasound was used for the synthesis of BGNPF. The particles obtained were characterized by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), atomic force microscopy (AFM), X-ray diffraction (XRD), dynamic light scattering (DLS), nitrogen adsorption, and X-ray photoelectron spectroscopy (XPS). SEM micrographs showed that the particles are quite uniform spherical nanostructures, occurring agglomeration or partial sinterization of the particulate system after heat treatment. XRD and XPS analysis results suggest the formation of fluorapatite crystals embedded within the matrix of the bioactive glass nanoparticles. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 360-366, 2018. © 2017 Wiley Periodicals, Inc.

  12. Fast and versatile microwave-assisted intramolecular Heck reaction in peptide macrocyclization using microwave energy.

    Science.gov (United States)

    Byk, Gerardo; Cohen-Ohana, Mirit; Raichman, Daniel

    2006-01-01

    We have revisited the intramolecular Heck reaction and investigated the microwave-assisted macrocyclization on preformed peptides using a model series of ring-varying peptides acryloyl-Gly-[Gly](n)-Phe(4-I)NHR; n = 0-4. The method was applied to both solution and solid supported cyclizations. We demonstrate that the intramolecular Heck reaction can be performed in peptides both in solution and solid support using a modified domestic microwave within 1 to 30 minutes in DMF under reflux with moderate yields ranging from 15 to 25% for a scale between 2-45 mg of linear precursors. The approach was applied to the synthesis of a constrained biologically relevant peptidomimetic bearing an Arg-Gly-Asp (RGD) sequence. These results make the microwave-assisted Heck reaction an attractive renovated approach for peptidomimetics. Copyright 2006 Wiley Periodicals, Inc.

  13. Large-Scale Fabrication of Boron Nitride Nanotubes via a Facile Chemical Vapor Reaction Route and Their Cathodoluminescence Properties

    Directory of Open Access Journals (Sweden)

    Zhong Bo

    2011-01-01

    Full Text Available Abstract Cylinder- and bamboo-shaped boron nitride nanotubes (BNNTs have been synthesized in large scale via a facile chemical vapor reaction route using ammonia borane as a precursor. The structure and chemical composition of the as-synthesized BNNTs are extensively characterized by X-ray diffraction, scanning electron microscopy, high-resolution transmission electron microscopy, and selected-area electron diffraction. The cylinder-shaped BNNTs have an average diameter of about 100 nm and length of hundreds of microns, while the bamboo-shaped BNNTs are 100–500 nm in diameter with length up to tens of microns. The formation mechanism of the BNNTs has been explored on the basis of our experimental observations and a growth model has been proposed accordingly. Ultraviolet–visible and cathodoluminescence spectroscopic analyses are performed on the BNNTs. Strong ultraviolet emissions are detected on both morphologies of BNNTs. The band gap of the BNNTs are around 5.82 eV and nearly unaffected by tube morphology. There exist two intermediate bands in the band gap of BNNTs, which could be distinguishably assigned to structural defects and chemical impurities. Additional file 1 Click here for file

  14. Label-assisted mass spectrometry for the acceleration of reaction discovery and optimization

    Science.gov (United States)

    Cabrera-Pardo, Jaime R.; Chai, David I.; Liu, Song; Mrksich, Milan; Kozmin, Sergey A.

    2013-05-01

    The identification of new reactions expands our knowledge of chemical reactivity and enables new synthetic applications. Accelerating the pace of this discovery process remains challenging. We describe a highly effective and simple platform for screening a large number of potential chemical reactions in order to discover and optimize previously unknown catalytic transformations, thereby revealing new chemical reactivity. Our strategy is based on labelling one of the reactants with a polyaromatic chemical tag, which selectively undergoes a photoionization/desorption process upon laser irradiation, without the assistance of an external matrix, and enables rapid mass spectrometric detection of any products originating from such labelled reactants in complex reaction mixtures without any chromatographic separation. This method was successfully used for high-throughput discovery and subsequent optimization of two previously unknown benzannulation reactions.

  15. Reaction time for processing visual stimulus in a computer-assisted rehabilitation environment.

    Science.gov (United States)

    Sanchez, Yerly; Pinzon, David; Zheng, Bin

    2017-10-01

    To examine the reaction time when human subjects process information presented in the visual channel under both a direct vision and a virtual rehabilitation environment when walking was performed. Visual stimulus included eight math problems displayed on the peripheral vision to seven healthy human subjects in a virtual rehabilitation training (computer-assisted rehabilitation environment (CAREN)) and a direct vision environment. Subjects were required to verbally report the results of these math calculations in a short period of time. Reaction time measured by Tobii Eye tracker and calculation accuracy were recorded and compared between the direct vision and virtual rehabilitation environment. Performance outcomes measured for both groups included reaction time, reading time, answering time and the verbal answer score. A significant difference between the groups was only found for the reaction time (p = .004). Participants had more difficulty recognizing the first equation of the virtual environment. Participants reaction time was faster in the direct vision environment. This reaction time delay should be kept in mind when designing skill training scenarios in virtual environments. This was a pilot project to a series of studies assessing cognition ability of stroke patients who are undertaking a rehabilitation program with a virtual training environment. Implications for rehabilitation Eye tracking is a reliable tool that can be employed in rehabilitation virtual environments. Reaction time changes between direct vision and virtual environment.

  16. Cu2ZnSnS4 thin films by simple replacement reaction route for solar photovoltaic application

    International Nuclear Information System (INIS)

    Tiwari, Devendra; Chaudhuri, Tapas K.; Ray, Arabinda; Tiwari, Krishan Dutt

    2014-01-01

    A process for deposition of Cu 2 ZnSnS 4 (CZTS) films using replacement of Zn 2+ in ZnS is demonstrated. X-ray diffraction pattern and Raman spectroscopy confirm the formation of pure CZTS. Atomic force microscopy shows the films to be homogeneous and compact with root mean squared roughness of 6 nm. The direct band gap of CZTS films as elucidated by UV–Vis-NIR spectroscopy is 1.45 eV. The CZTS films exhibit p-type conduction with electrical conductivity of 4.6 S/cm. The hole concentration and hole mobility is determined to be 3.6 × 10 17 cm −3 and 1.4 cm 2 V −1 s −1 respectively. Solar cells with structure: graphite/CZTS/CdS/ZnO/SnO 2 :In/Soda lime glass are also fabricated, gave photo-conversion efficiency of 6.17% with open circuit voltage and short circuit current density of 521 mV and 19.13 mA/cm 2 , respectively and a high fill factor of 0.62. The external quantum efficiency of the solar cell lies above 60% in the visible region. - Highlights: • Pure kesterite Cu 2 ZnSnS 4 thin films deposited by replacement reaction route • Energy band gap of films is 1.45 eV. • p-type films with conductivity of 4.6 S/cm and mobility of 1.4 cm 2 S −1 V −1 • Fabrication of Graphite/Cu 2 ZnSnS 4 /CdS/ZnO/SnO 2 :In/Glass solar cell • Solar cell delivered efficiency of 6.17% with high fill factor of 0.62

  17. Kinetics of subdiffusion-assisted reactions: non-Markovian stochastic Liouville equation approach

    International Nuclear Information System (INIS)

    Shushin, A I

    2005-01-01

    Anomalous specific features of the kinetics of subdiffusion-assisted bimolecular reactions (time-dependence, dependence on parameters of systems, etc) are analysed in detail with the use of the non-Markovian stochastic Liouville equation (SLE), which has been recently derived within the continuous-time random-walk (CTRW) approach. In the CTRW approach, subdiffusive motion of particles is modelled by jumps whose onset probability distribution function is of a long-tailed form. The non-Markovian SLE allows for rigorous describing of some peculiarities of these reactions; for example, very slow long-time behaviour of the kinetics, non-analytical dependence of the reaction rate on the reactivity of particles, strong manifestation of fluctuation kinetics showing itself in very slowly decreasing behaviour of the kinetics at very long times, etc

  18. Comparison of TiO2 photocatalysis, electrochemically assisted Fenton reaction and direct electrochemistry for simulation of phase I metabolism reactions of drugs

    NARCIS (Netherlands)

    Ruokolainen, Miina; Gül, Turan; Permentier, Hjalmar; Sikanen, Tiina; Kostiainen, Risto; Kotiaho, Tapio

    2016-01-01

    The feasibility of titanium dioxide (TiO2) photocatalysis, electrochemically assisted Fenton reaction (EC-Fenton) and direct electrochemical oxidation (EC) for simulation of phase I metabolism of drugs was studied by comparing the reaction products of buspirone, promazine, testosterone and

  19. Understanding recovery in children following traffic-related injuries: exploring acute traumatic stress reactions, child coping, and coping assistance.

    Science.gov (United States)

    Marsac, Meghan L; Donlon, Katharine A; Hildenbrand, Aimee K; Winston, Flaura K; Kassam-Adams, Nancy

    2014-04-01

    Millions of children incur potentially traumatic physical injuries every year. Most children recover well from their injury but many go on to develop persistent traumatic stress reactions. This study aimed to describe children's coping and coping assistance (i.e., the ways in which parents and peers help children cope) strategies and to explore the association between coping and acute stress reactions following an injury. Children (N = 243) rated their acute traumatic stress reactions within one month of injury and reported on coping and coping assistance six months later. Parents completed a measure of coping assistance at the six-month assessment. Children used an average of five to six coping strategies (out of 10), with wishful thinking, social support, and distraction endorsed most frequently. Child coping was associated with parent and peer coping assistance strategies. Significant acute stress reactions were related to subsequent child use of coping strategies (distraction, social withdrawal, problem-solving, blaming others) and to child report of parent use of distraction (as a coping assistance strategy). Findings suggest that children's acute stress reactions may influence their selection of coping and coping assistance strategies. To best inform interventions, research is needed to examine change in coping behaviors and coping assistance over time, including potential bidirectional relationships between trauma reactions and coping.

  20. Liquid-assisted grinding and ion pairing regulates percentage conversion and diastereoselectivity of the Wittig reaction under mechanochemical conditions.

    Science.gov (United States)

    Denlinger, Kendra Leahy; Ortiz-Trankina, Lianna; Carr, Preston; Benson, Kingsley; Waddell, Daniel C; Mack, James

    2018-01-01

    Mechanochemistry is maturing as a discipline and continuing to grow, so it is important to continue understanding the rules governing the system. In a mechanochemical reaction, the reactants are added into a vessel along with one or more grinding balls and the vessel is shaken at high speeds to facilitate a chemical reaction. The dielectric constant of the solvent used in liquid-assisted grinding (LAG) and properly chosen counter-ion pairing increases the percentage conversion of stilbenes in a mechanochemical Wittig reaction. Utilizing stepwise addition/evaporation of ethanol in liquid-assisted grinding also allows for the tuning of the diastereoselectivity in the Wittig reaction.

  1. Decolourization of methyl orange using iron- immobilize MKSF in UV assisted Fenton-like reaction

    Science.gov (United States)

    Abdullah, N. H.; Zubir, N. A.; Hassan, H.

    2017-09-01

    In this work, montmorillonite KSF clay was used to immobilize iron species as a potential heterogeneous UV assisted Fenton-like reaction. Iron-immobilized MKSF (Fe-MKSF) was synthesized via hydrothermal method in an autoclave. Fe-MKSF was tested on methyl orange (MO) removal by adsorption (5%) and hydrogen peroxide (H2O2) activation (63%) and these prominent margins proved Fe-MKSF performance was attributed by UV assisted Fenton-like reaction. Fe-MKSF show superior performance with 63% color removal within 180 mins reaction in comparison to iron oxide and pristine MKSF. The Fe-MKSF increased in the surface area from 91.1 to 101.9 m2/g and pore volume from 0.13 to 0.45 cm3/g compared to pristine MKSF. The SEM images of Fe-MKSF show iron aggregates indicating successful immobilizing process and the elemental weight percent of iron which increase from 6.12% to 55.38% in Fe-MKSF. These findings prove Fe-MKSF as a promising alternative catalyst in dye contaminated wastewater treatment.

  2. Gas to liquid to solid transition in halogen hot atom chemistry. 6. Product formation routes and chemical selectivity of high energy iodine reactions with butyne isomers

    International Nuclear Information System (INIS)

    Garmestani, S.K.; Firouzbakht, M.L.; Rack, E.P.

    1979-01-01

    Reactions of recoil produced iodine-128 with isomers of butyne were studied in gaseous, high pressure, and condensed phase conditions, with rare gas additives and in the presence and absence of radical scavengers (I 2 and O 2 ). It was found that recoil iodine-128 reactions were initiated by thermal electronically excited I + species for both 1-butyne and 2-butyne systems. While the diverse and complex nature of the reactions cannot be explained by simple chemical parameters, comparisons among the alkyne systems demonstrate preferential attack of iodine at the triple bond resulting, mainly, in electronically excited intermediates. A comparison of the various product formation routes results in the characterization of general traits common to the alkynes. 6 figures, 4 tables

  3. Synthesis of high intrinsic loss power aqueous ferrofluids of iron oxide nanoparticles by citric acid-assisted hydrothermal-reduction route

    International Nuclear Information System (INIS)

    Behdadfar, Behshid; Kermanpur, Ahmad; Sadeghi-Aliabadi, Hojjat; Morales, Maria del Puerto; Mozaffari, Morteza

    2012-01-01

    Monodispersed aqueous ferrofluids of iron oxide nanoparticle were synthesized by hydrothermal-reduction route. They were characterized by X-ray diffraction analysis, Fourier transform infrared spectroscopy, scanning and transmission electron microscopy and dynamic light scattering. The results showed that certain concentrations of citric acid (CA) are required to obtain only magnetic iron oxides with mean particle sizes around 8 nm. CA acts as a modulator and reducing agent in iron oxide formation which controls nanoparticle size. The XRD, magnetic and heating measurements showed that the temperature and time of hydrothermal reaction can affect the magnetic properties of obtained ferrofluids. The synthesized ferrofluids were stable at pH 7. Their mean hydrodynamic size was around 80 nm with polydispersity index (PDI) of 0.158. The calculated intrinsic loss power (ILP) was 9.4 nHm 2 /kg. So this clean and cheap route is an efficient way to synthesize high ILP aqueous ferrofluids applicable in magnetic hyperthermia. - Graphical abstract: Monodispersed aqueous ferrofluids of iron oxide nanoparticles were synthesized by hydrothermal-reduction method with citric acid as reductant which is an efficient way to synthesize aqueous ferrofluids applicable in magnetic hyperthermia. Highlights: ► Aqueous iron oxide ferrofluids were synthesized by hydrothermal-reduction route. ► Citric acid acted as reducing agent and surfactant in the route. ► This is a facile, low energy and environmental friendly route. ► The aqueous iron oxide ferrofluids were monodispersed and stable at pH of 7. ► The calculated intrinsic loss power of the synthesized ferrofluids was very high.

  4. Designing driver assistance systems with crossmodal signals: multisensory integration rules for saccadic reaction times apply.

    Directory of Open Access Journals (Sweden)

    Rike Steenken

    Full Text Available Modern driver assistance systems make increasing use of auditory and tactile signals in order to reduce the driver's visual information load. This entails potential crossmodal interaction effects that need to be taken into account in designing an optimal system. Here we show that saccadic reaction times to visual targets (cockpit or outside mirror, presented in a driving simulator environment and accompanied by auditory or tactile accessories, follow some well-known spatiotemporal rules of multisensory integration, usually found under confined laboratory conditions. Auditory nontargets speed up reaction time by about 80 ms. The effect tends to be maximal when the nontarget is presented 50 ms before the target and when target and nontarget are spatially coincident. The effect of a tactile nontarget (vibrating steering wheel was less pronounced and not spatially specific. It is shown that the average reaction times are well-described by the stochastic "time window of integration" model for multisensory integration developed by the authors. This two-stage model postulates that crossmodal interaction occurs only if the peripheral processes from the different sensory modalities terminate within a fixed temporal interval, and that the amount of crossmodal interaction manifests itself in an increase or decrease of second stage processing time. A qualitative test is consistent with the model prediction that the probability of interaction, but not the amount of crossmodal interaction, depends on target-nontarget onset asynchrony. A quantitative model fit yields estimates of individual participants' parameters, including the size of the time window. Some consequences for the design of driver assistance systems are discussed.

  5. Increasing the Intensity over Time of an Electric-Assist Bike Based on the User and Route: The Bike Becomes the Gym

    Directory of Open Access Journals (Sweden)

    Daniel H. De La Iglesia

    2018-01-01

    Full Text Available Nowadays, many citizens have busy days that make finding time for physical activity difficult. Thus, it is important to provide citizens with tools that allow them to introduce physical activity into their lives as part of the day’s routine. This article proposes an app for an electric pedal-assist-system (PAS bicycle that increases the pedaling intensity so the bicyclist can achieve higher and higher levels of physical activity. The app includes personalized assist levels that have been adapted to the user’s strength/ability and a profile of the route, segmented according to its slopes. Additionally, a social component motivates interaction and competition between users based on a scoring system that shows the level of their performances. To test the training module, a case study in three different European countries lasted four months and included nine people who traveled 551 routes. The electric PAS bicycle with the app that increases intensity of physical activity shows promise for increasing levels of physical activity as a regular part of the day.

  6. An alternative route for the preparation of the medical isotope 99Mo from the 238U(γ, f) and 100Mo(γ, n) reactions

    International Nuclear Information System (INIS)

    Naik, H.; Goswami, A.; Suryanarayana, S.V.; Jagadeesan, K.C.; Thakare, S.V.; Joshi, P.V.; Nimje, V.T.; Mittal, K.C.; Venugopal, V.; Kailas, S.

    2013-01-01

    The radionuclide 99 Mo, which has a half-life of 65.94 h was produced from 238 U(γ, f) and 100 Mo(γ, n) reactions using a 10 MeV electron linac at EBC, Kharghar Navi-Mumbai, India. This has been investigated since the daughter product 99m Tc is very important from a medical point of view and can be produced in a generator from the parent 99 Mo. The activity of 99 Mo was analyzed by a γ-ray spectrometric technique using a HPGe detector. From the detected γ-rays activity of 140.5 and 739.8 keV, the amount of 99 Mo produced was determined. For comparison, the amount of 99 Mo from 238 U(γ, f) and 100 Mo(γ, n) reactions was also estimated using the experimental photon flux from 197 Au(γ, n) 196 Au reaction. The amount of 99 Mo from the detected γ-lines is in agreement with the estimated value for 238 U(γ, f) and 100 Mo(γ, n) reactions. The production of 99 Mo activity from 238 U(γ, f) and 100 Mo(γ, n) reactions is a relevant and novel approach, which provides alternative routes to 235,238 U(n, f) and 98 Mo(n, γ) reactions, circumventing the need for a reactor. The viability and practicality of the 99 Mo production from the 238 U(γ, f) and 100 Mo(γ, n) reactions alternative to 235,238 U(n, f) and 98 Mo(n, γ) reactions has been emphasize. An estimate has been also arrived based on the experimental data of present work to fulfill the requirement of DOE. (author)

  7. CRISPR/Cas9-Assisted Transformation-Efficient Reaction (CRATER) for Near-Perfect Selective Transformation

    Science.gov (United States)

    Rothschild, Lynn J.; Greenberg, Daniel T.; Takahashi, Jack R.; Thompson, Kirsten A.; Maheshwari, Akshay J.; Kent, Ryan E.; McCutcheon, Griffin; Shih, Joseph D.; Calvet, Charles; Devlin, Tyler D.; hide

    2015-01-01

    The CRISPR (Clustered, Regularly Interspaced, Short Palindromic Repeats)/Cas9 system has revolutionized genome editing by providing unprecedented DNA-targeting specificity. Here we demonstrate that this system can be also applied in vitro to fundamental cloning steps to facilitate efficient plasmid selection for transformation and selective gene insertion into plasmid vectors by cleaving unwanted plasmid byproducts with a single-guide RNA (sgRNA)-Cas9 nuclease complex. Using fluorescent and chromogenic proteins as reporters, we demonstrate that CRISPR/Cas9 cleavage excludes multiple plasmids as well as unwanted ligation byproducts resulting in an unprecedented increase in the transformation success rate from approximately 20% to nearly 100%. Thus, this CRISPR/Cas9-Assisted Transformation-Efficient Reaction (CRATER) protocol is a novel, inexpensive, and convenient application to conventional molecular cloning to achieve near-perfect selective transformation.

  8. Charge Exchange Reaction in Dopant-Assisted Atmospheric Pressure Chemical Ionization and Atmospheric Pressure Photoionization.

    Science.gov (United States)

    Vaikkinen, Anu; Kauppila, Tiina J; Kostiainen, Risto

    2016-08-01

    The efficiencies of charge exchange reaction in dopant-assisted atmospheric pressure chemical ionization (DA-APCI) and dopant-assisted atmospheric pressure photoionization (DA-APPI) mass spectrometry (MS) were compared by flow injection analysis. Fourteen individual compounds and a commercial mixture of 16 polycyclic aromatic hydrocarbons were chosen as model analytes to cover a wide range of polarities, gas-phase ionization energies, and proton affinities. Chlorobenzene was used as the dopant, and methanol/water (80/20) as the solvent. In both techniques, analytes formed the same ions (radical cations, protonated molecules, and/or fragments). However, in DA-APCI, the relative efficiency of charge exchange versus proton transfer was lower than in DA-APPI. This is suggested to be because in DA-APCI both dopant and solvent clusters can be ionized, and the formed reagent ions can react with the analytes via competing charge exchange and proton transfer reactions. In DA-APPI, on the other hand, the main reagents are dopant-derived radical cations, which favor ionization of analytes via charge exchange. The efficiency of charge exchange in both DA-APPI and DA-APCI was shown to depend heavily on the solvent flow rate, with best efficiency seen at lowest flow rates studied (0.05 and 0.1 mL/min). Both DA-APCI and DA-APPI showed the radical cation of chlorobenzene at 0.05-0.1 mL/min flow rate, but at increasing flow rate, the abundance of chlorobenzene M(+.) decreased and reagent ion populations deriving from different gas-phase chemistry were recorded. The formation of these reagent ions explains the decreasing ionization efficiency and the differences in charge exchange between the techniques. Graphical Abstract ᅟ.

  9. Reaction-assisted diffusion bonding of TiAl alloy to steel

    Energy Technology Data Exchange (ETDEWEB)

    Simões, S., E-mail: ssimoes@fe.up.pt [CEMUC, Department of Metallurgical and Materials Engineering, University of Porto, R. Dr. Roberto Frias, 4200-465 Porto (Portugal); Viana, F. [CEMUC, Department of Metallurgical and Materials Engineering, University of Porto, R. Dr. Roberto Frias, 4200-465 Porto (Portugal); Ramos, A.S.; Vieira, M.T. [CEMUC, Department of Mechanical Engineering, University of Coimbra, R. Luís Reis Santos, 3030-788 Coimbra (Portugal); Vieira, M.F. [CEMUC, Department of Metallurgical and Materials Engineering, University of Porto, R. Dr. Roberto Frias, 4200-465 Porto (Portugal)

    2016-03-01

    The dissimilar joining of TiAl to AISI 310 stainless steel by a reaction-assisted diffusion bonding process, using Ni/Al nanolayers as an interlayer, was investigated in the present work. The Ni and Al alternated nanolayers were deposited by d.c. magnetron sputtering onto the base materials, with a bilayer thickness of 14 nm. Joining experiments were performed at 800 °C for 60 min with compressive stress of 25 and 50 MPa. The effectiveness of the interlayer on the bonding process was assessed by microstructural characterization of the interface and by mechanical tests. Diffusion bonded joints were characterized by scanning electron microscopy (SEM), electron backscatter diffraction (EBSD), transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM), scanning transmission electron microscopy (STEM) and analyzed by energy dispersive X-ray spectroscopy (EDS) in SEM and TEM and Fast Fourier Transform (FFT). The thickness of the interface region, together with its microstructural and mechanical characteristics, is affected by the use of Ni/Al multilayers; which promote joints with lower hardness values, closer to the values of the base materials, and exhibit higher shear strength. - Highlights: • Dissimilar joining by a reaction-assisted diffusion bonding were studied. • Ni/Al nanolayers allows join TiAl to steel in less demanding processing conditions. • The microstructural and mechanical characterization of the joints were investigated. • The fracture occurring in the TiAl base material attests to the sound joining. • Shear strength value decreases for joints with base materials without nanolayers.

  10. A route to hydroxylfluorenes: TsOH-mediated condensation reactions of 1,3-diketones with propargylic alcohols

    KAUST Repository

    Yao, Liangfeng; Tan, Davin; Miao, Xiaohe; Huang, Kuo-Wei

    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

  11. An exonuclease-assisted amplification electrochemical aptasensor for Hg(2+) detection based on hybridization chain reaction.

    Science.gov (United States)

    Bao, Ting; Wen, Wei; Zhang, Xiuhua; Xia, Qinghua; Wang, Shengfu

    2015-08-15

    In this work, a novel electrochemical aptasensor was developed for Hg(2+) detection based on exonuclease-assisted target recycling and hybridization chain reaction (HCR) dual signal amplification strategy. The presence of Hg(2+) induced the T-rich DNA partly folded into duplex-like structure via the Hg(2+) mediated T-Hg(2+)-T base pairs, which triggered the activity of exonuclease III (Exo III). Exo III selectively digested the double-strand DNA containing multiple T-Hg(2+)-T base pairs from its 3'-end, the released Hg(2+) participated analyte recycle. With each digestion cycle, a digestion product named as help DNA was obtained, which acted as a linkage between the capture DNA and auxiliary DNA. The presence of help DNA and two auxiliary DNA collectively facilitated successful HCR process and formed long double-stranded DNA. [Ru(NH3)6](3+) was used as redox indicator, which electrostatically bound to the double strands and produced an electrochemical signal. Exo III-assisted target recycling and HCR dual amplification significantly improved the sensitivity for Hg(2+) with a detection limit of 0.12 pM (S/N=3). Furthermore, the proposed aptasensor had a promising potential for the application of Hg(2+) detection in real aquatic sample analysis. Copyright © 2015 Elsevier B.V. All rights reserved.

  12. The cross sections of fusion-evaporation reactions: the most promising route to superheavy elements beyond Z=118

    Directory of Open Access Journals (Sweden)

    Jadambaa Khuyagbaatar

    2017-01-01

    Full Text Available The synthesis of superheavy elements beyond oganesson (Og, which has atomic number Z = 118, is currently one of the main topics in nuclear physics. An absence of sufficient amounts of target material with atomic numbers heavier than californium (Z = 98 forces the use of projectiles heavier than 48Ca (Z = 20, which has been successfully used for the discoveries of elements with Z = 114 - 118 in complete fusion reactions. Experimental cross sections of 48Ca with actinide targets behave very differently to “cold” and “hot” fusion-evaporation reactions, where doubly-magic lead and deformed actinides are used as targets, respectively. The known cross sections of these reactions have been analysed compared to calculated fission barriers. It has been suggested that observed discrepancies between the cross sections of 48Ca-induced and other fusionevaporation reactions originate from the shell structure of the compound nucleus, which lies in the island of the stability. Besides scarcely known data on other reactions involving heavier projectiles, the most promising projectile for the synthesis of the elements beyond Og seems to be 50Ti. However, detailed studies of 50Ti, 54Cr, 58Fe and 64Ni-induced reactions are necessary to be performed in order to fully understand the complexities of superheavy element formation.

  13. The cross sections of fusion-evaporation reactions: the most promising route to superheavy elements beyond Z=118

    Science.gov (United States)

    Jadambaa, Khuyagbaatar

    2017-11-01

    The synthesis of superheavy elements beyond oganesson (Og), which has atomic number Z = 118, is currently one of the main topics in nuclear physics. An absence of sufficient amounts of target material with atomic numbers heavier than californium (Z = 98) forces the use of projectiles heavier than 48Ca (Z = 20), which has been successfully used for the discoveries of elements with Z = 114 - 118 in complete fusion reactions. Experimental cross sections of 48Ca with actinide targets behave very differently to "cold" and "hot" fusion-evaporation reactions, where doubly-magic lead and deformed actinides are used as targets, respectively. The known cross sections of these reactions have been analysed compared to calculated fission barriers. It has been suggested that observed discrepancies between the cross sections of 48Ca-induced and other fusionevaporation reactions originate from the shell structure of the compound nucleus, which lies in the island of the stability. Besides scarcely known data on other reactions involving heavier projectiles, the most promising projectile for the synthesis of the elements beyond Og seems to be 50Ti. However, detailed studies of 50Ti, 54Cr, 58Fe and 64Ni-induced reactions are necessary to be performed in order to fully understand the complexities of superheavy element formation.

  14. The Production of Biodiesel and Bio-kerosene from Coconut Oil Using Microwave Assisted Reaction

    Science.gov (United States)

    SAIFUDDIN, N.; SITI FAZLILI, A.; KUMARAN, P.; PEI-JUA, N.; PRIATHASHINI, P.

    2016-03-01

    Biofuels including biodiesel, an alternative fuel, is renewable, environmentally friendly, non-toxic and low emissions. The raw material used in this work was coconut oil, which contained saturated fatty acids about 90% with high percentage of medium chain (C8-C12), especially lauric acid and myristic acid. The purpose of this research was to study the effect of power and NaOH catalyst in transesterification assisted by microwave for production of biofuels (biodiesel and bio-kerosene) derived from coconut oil. The reaction was performed with oil and methanol using mole ratio of 1:6, catalyst concentration of 0.6% with microwave power at 100W, 180W, 300W, 450W, 600W, and 850W. The reaction time was set at of 3, 5, 7, 10 and 15 min. The results showed that microwave could accelerate the transesterification process to produce biodiesel and bio-kerosene using NaOH catalyst. The highest yield of biodiesel was 97.17 %, or 99.05 % conversion at 5 min and 100W microwave power. Meanwhile, the bio-kerosene obtained was 65% after distillation.

  15. Microwave-Assisted Synthesis of Nanoporous Aluminum-Based Coordination Polymers as Catalysts for Selective Sulfoxidation Reaction

    Directory of Open Access Journals (Sweden)

    Madhan Vinu

    2017-10-01

    Full Text Available A series of aluminum-based coordination polymers or metal–organic frameworks (Al–MOFs, i.e., DUT-4, DUT-5, MIL-53, NH2-MIL-53, and MIL-100, have been facile prepared by microwave (MW-assisted reactions and used as catalysts for selective sulfoxidation reactions. The MW-assisted synthesis drastically reduced the reaction time from few days to hours. The prepared MOFs have smaller and uniform particle sizes and better yield compared to conventional hydrothermal method. Furthermore, the Al–MOFs have been successfully demonstrated as catalysts in oxidation reaction of methyl phenyl sulfide with H2O2 as oxidant, even under mild conditions, with more than 95% conversion.

  16. Lithium-Assisted Copolymerization of CO 2 /Cyclohexene Oxide: A Novel and Straightforward Route to Polycarbonates and Related Block Copolymers

    KAUST Repository

    Zhang, Dongyue

    2016-03-23

    A facile route toward alternating polycarbonates by anionic copolymerization of carbon dioxide (CO2) and cyclohexene oxide (CHO), using lithium halide or alkoxide as initiators and triisobutylaluminum (TiBA) as activator, is reported. α,ω-Heterobifunctional and α,ω-dihydroxypoly(cyclohexene carbonate)s (PCHC) as well as poly(CHC-co-CHO) copolymers with different carbonate composition could also be easily synthesized by adjusting the amount of TiBA or by adding inert lithium salts. The value of this initiating system also resides in the easy access to PSt-b-PCHC (PSt: polystyrene) and PI-b-PCHC (PI: polyisoprene) block copolymers which can be derived by mere one-pot sequential addition of styrene or dienes first and then of CO2 and CHO under the same experimental conditions. © 2016 American Chemical Society.

  17. Synthesis, characterization and catalytic performance of mixed nanoferrites submitted to transesterification and esterification reaction using methyl and ethyl route for biodiesel production

    International Nuclear Information System (INIS)

    Dantas, Joelda; Leal, Elvia; Mapossa, Antonio Benjamim; Silva, Adriano Sant'Ana; Costa, Ana Cristina Figueiredo de Melo

    2016-01-01

    The mixed nanoferrites of Ni_0_._5Zn_0_._5Fe_2O_4 and Ni_0_._2Cu_0_._3Zn_0_._5Fe_2O_4 were synthesized by combustion reaction using urea as fuel and a conical reactor as heating source in batches of 10 g, and then tested as heterogeneous nanocatalysts in the transesterification and esterification reaction of soya bean oil using the methyl and ethyl routes to biodiesel production. During the synthesis the time and temperature of the reactions were measured, and the evolved gases and the color of the emitted flames were observed. The samples were characterized by XRD, EDX, FTIR, SEM/EDS, BET and gas chromatography. The reaction tests were carried out with 10 g of oil for 1 h, oil:alcohol molar ratio of 1:12, 2 % (w/w) of catalyst, and conducted at 180 °C. The XRD patterns and the FTIR spectra revealed the presence of the inverse spinel phase type B(AB)_2O_4. The morphology showed the formation of agglomerates with fragile morphology and high surface area. The chromatographic analysis produced excellent results in the esterification reactions for both samples in the tested conditions, with special emphasis on Ni_0_._5Zn_0_._5Fe_2O_4, whose conversions were of 91.4 % in methyl esters and of 77.8 % in ethyl esters, while the Ni_0_._2Cu_0_._3Zn_0_._5Fe_2O_4 sample showed conversion of 75.1 and 65.1 %, respectively. The conversions in the methyl and ethyl transesterification were of 14 and 2 % of the Ni_0_._5Zn_0_._5Fe_2O_4 sample, and of 11 and 3 % for the Ni_0_._2Cu_0_._3Zn_0_._5Fe_2O_4 sample. (author)

  18. Computer-assisted design for scaling up systems based on DNA reaction networks.

    Science.gov (United States)

    Aubert, Nathanaël; Mosca, Clément; Fujii, Teruo; Hagiya, Masami; Rondelez, Yannick

    2014-04-06

    In the past few years, there have been many exciting advances in the field of molecular programming, reaching a point where implementation of non-trivial systems, such as neural networks or switchable bistable networks, is a reality. Such systems require nonlinearity, be it through signal amplification, digitalization or the generation of autonomous dynamics such as oscillations. The biochemistry of DNA systems provides such mechanisms, but assembling them in a constructive manner is still a difficult and sometimes counterintuitive process. Moreover, realistic prediction of the actual evolution of concentrations over time requires a number of side reactions, such as leaks, cross-talks or competitive interactions, to be taken into account. In this case, the design of a system targeting a given function takes much trial and error before the correct architecture can be found. To speed up this process, we have created DNA Artificial Circuits Computer-Assisted Design (DACCAD), a computer-assisted design software that supports the construction of systems for the DNA toolbox. DACCAD is ultimately aimed to design actual in vitro implementations, which is made possible by building on the experimental knowledge available on the DNA toolbox. We illustrate its effectiveness by designing various systems, from Montagne et al.'s Oligator or Padirac et al.'s bistable system to new and complex networks, including a two-bit counter or a frequency divider as well as an example of very large system encoding the game Mastermind. In the process, we highlight a variety of behaviours, such as enzymatic saturation and load effect, which would be hard to handle or even predict with a simpler model. We also show that those mechanisms, while generally seen as detrimental, can be used in a positive way, as functional part of a design. Additionally, the number of parameters included in these simulations can be large, especially in the case of complex systems. For this reason, we included the

  19. A Convenient Route to Higher Sugars by Two-Carbon Chain Elongation Using Wittig/Dihydroxylation Reactions

    DEFF Research Database (Denmark)

    Jørgensen, Morten; Iversen, Erik Høgh; Madsen, Robert

    2001-01-01

    The combination of a Wittig olefination and a dihydroxylation reaction constitutes a facile synthetic protocol for the transformation of unprotected carbohydrates into higher sugars. The Wittig reaction is carried out with tert-butyl or diphenylmethyl ester stabilized phosphoranes to give (E......)-configured alpha,beta -unsaturated esters as the only products in most cases. These are dihydroxylated in a diastereoselective fashion using OsO4/NMO. The stereochemical outcome in the dihydroxylation follows Kishi's empirical rule and gives high diastereoselectivity (5:1-8:1) when starting from sugars with the 2......,3-threo configuration. When starting from sugars with the 2,3-erythro configuration, the diastereoselectivity in the dihydroxylation is low (2:1-2.5:1). As a result, the Wittig/dihydroxylation protocol is most effective for producing higher sugars with the galacto configuration at the reducing end...

  20. Effect of reaction parameters on photoluminescence and photocatalytic activity of zinc sulfide nanosphere synthesized by hydrothermal route

    Energy Technology Data Exchange (ETDEWEB)

    Chanu, T. Inakhunbi; Samanta, Dhrubajyoti [Centre for Material Science and Nanotechnology, Sikkim Manipal Institute of Technology, Sikkim Manipal University, Sikkim 737136 (India); Tiwari, Archana [Department of Physics, Sikkim University, 737102 Sikkim (India); Chatterjee, Somenath, E-mail: somenath@gmail.com [Centre for Material Science and Nanotechnology, Sikkim Manipal Institute of Technology, Sikkim Manipal University, Sikkim 737136 (India); Electronics & Communication Engineering Department, Sikkim Manipal Institute of Technology, Sikkim Manipal University, Sikkim 737136 (India)

    2017-01-01

    Highlights: • ZnS nanosphere synthesis in hydrothermal method with biomolecule as capping ligand. • Effect of reaction parameters to tune the size of ZnS nanoparticles. • Obtain multiple defect emission, which arises from interstitials/vacancies. • 87% degradation of Rh-B in the presence of ZnS nanoparticles under solar radiation. - Abstract: Zinc Sulfide (ZnS) nanospheres have been synthesized using amino acid, L-Histidine as a capping agent by hydrothermal method. The as prepared ZnS have been characterised using X-ray Diffraction (XRD), Field Emission Scanning Electron Microscopy (FESEM), High Resolution Transmission Electron Microscopy (HRTEM), Photoluminescence (PL), Fourier Transform Infra-Red spectroscopy (FTIR), UV–vis absorption spectroscopy and X-ray Photo Electron Spectroscopy (XPS). Effect of reaction parameters on particle size has been investigated. The morphology and size of the ZnS can be tuned based on the reaction parameters. ZnS nanosphere with a particle size of 5 nm is obtained when the reaction parameters are kept at 120 °C for 3 h. The PL of ZnS shows multiple defect emissions arising from interstitials/vacancies. Particle size of ZnS nanoparticles plays an important role in determining the photo catalytic activity. A chronological study on synthesis of ZnS nanosphere and its photo catalytic activity under the sunlight are discussed here, which reveals the photo degradation of Rhodamine B (RhB) upto 87% as observed with ZnS nanosphere having a particle size of 5 nm.

  1. Sonic and microwaves assisted redox reactions of the hydrolysates of protein for the preparation of rechargeable battery

    International Nuclear Information System (INIS)

    Hussain, Z.; Khatak, K.; Sardar, A.

    2016-01-01

    Long recharging time is one of the serious limitations of batteries. One of the best solutions for quick redox reactions via the use of microwave and sound-assisted reversible redox reaction is presented in this work. A wireless charged prototype battery based on the redox reactions of hydrolyzed waste protein was designed. The effect of experimental conditions like time of charging, nature of media and strength of the acid on the voltage of this prototype battery was investigated. The experimental data was explained on the basis of the previous work on protein peptides and amino acids by various workers. (author)

  2. Green synthesis of tetrahydrobenzo[b]Pyrans by microwave assisted multi-component one-pot reactions in PEG-400.

    Science.gov (United States)

    Feng, Chun; Wang, Qiuyan; Lu, Cuifen; Yang, Guichun; Chen, Zuxing

    2012-01-01

    Polyethylene glycol is found to be a nontoxic and recyclable reaction medium for the microwave-assisted, multi-component one-pot reactions of aromatic aldehydes with ethyl-2-cyanoacetate and 1,3-cyclohexanedione or 5,5- dimethyl-1,3-cyclohexanedione in the presence of piperidine. This environmentally friendly microwave protocol offers ease of operation and enables recyclability of reaction medium and synthesis of a variety of substituted tetrahydrobenzo[b]pyran derivatives. It is an efficient, promising, and green synthetic strategy to construct tetrahydrobenzo[b]pyran skeleton.

  3. Correlating Internet Performance Changes and Route Changes to Assist in Trouble-shooting from an End-user Perspective

    Energy Technology Data Exchange (ETDEWEB)

    Logg, C

    2004-03-08

    With the growth of world wide data intensive scientific collaborations, there is a need to transfer large amounts of data to and from data repositories around the world. To effectively enable such transfers, high speed, predictable networks are needed. In turn, these require performance monitoring to ensure their quality. One tool/infrastructure that has been successfully used for the analysis and monitoring of critical paths is IEPM-BW. Based on experience gained from the achievable throughput monitoring in IEPM-BW, we developed ABwE, a tool to enable quick (< 1 second), low impact (40 packets) measurements of available bandwidth. Using ABwE we have been able to quickly detect significant changes in available bandwidth on production links up to 1Gbps, and report this information to the appropriate Network Operations Centers (NOCs) for repair, as such changes are often associated with route changes. This paper discusses this set of tools and their effectiveness together with examples of their utilization.

  4. Transesterification of Waste Frying Oil and Soybean Oil by Combi-lipases Under Ultrasound-Assisted Reactions.

    Science.gov (United States)

    Poppe, Jakeline Kathiele; Matte, Carla Roberta; Fernandez-Lafuente, Roberto; Rodrigues, Rafael C; Ayub, Marco Antônio Záchia

    2018-04-21

    This work describes the use of an ultrasound system for the enzymatic transesterification of oils using combi-lipases as biocatalyst. The reactions were carried out evaluating the individual use of waste oil and fresh soybean oil, and the immobilized lipases CALB, TLL, and RML were used as biocatalysts. It was performed in a mixture design of three factors to obtain the ideal mixture of lipases according to the composition of fatty acids present in each oil, and the main reaction variables were optimized. After 18 h of reaction, ultrasound provided a biodiesel yield of about 90% when using soybean oil and 70% using the waste oil. The results showed that ultrasound technology, in combination with the application of enzyme mixtures, known as combi-lipases, and the use of waste oil, could be a promising route to reduce the overall process costs of enzymatic production of biodiesel.

  5. Enhanced photocatalytic degradation of methylene blue by ZnO-reduced graphene oxide composite synthesized via microwave-assisted reaction

    Energy Technology Data Exchange (ETDEWEB)

    Lv Tian [Engineering Research Center for Nanophotonics and Advanced Instrument, Ministry of Education, Department of Physics, East China Normal University, Shanghai, 200062 (China); Pan Likun, E-mail: lkpan@phy.ecnu.edu.cn [Engineering Research Center for Nanophotonics and Advanced Instrument, Ministry of Education, Department of Physics, East China Normal University, Shanghai, 200062 (China); Liu Xinjuan; Lu Ting; Zhu Guang; Sun Zhuo [Engineering Research Center for Nanophotonics and Advanced Instrument, Ministry of Education, Department of Physics, East China Normal University, Shanghai, 200062 (China)

    2011-10-13

    Highlights: > ZnO-reduced graphene oxide composite is synthesized via microwave assisted reaction. > The method allows a facile, safe and rapid reaction in aqueous media. > A high dye degradation efficiency is achieved under UV light irradiation. - Abstract: A quick and facile microwave-assisted reaction is used to synthesize ZnO-reduced graphene oxide (RGO) hybrid composites by reducing graphite oxide dispersion with zinc nitrate using a microwave synthesis system. Their photocatalytic performance in degradation of methylene blue is investigated and the results show that the RGO plays an important role in the enhancement of photocatalytic performance and the ZnO-RGO composite with 1.1 wt. % RGO achieves a maximum degradation efficiency of 88% in a neutral solution under UV light irradiation for 260 min as compared with pure ZnO (68%) due to the increased light absorption, the reduced charge recombination with the introduction of RGO.

  6. Evaluating LSM-Based Water Budgets Over a West African Basin Assisted with a River Routing Scheme

    Science.gov (United States)

    Getirana, Augusto C. V.; Boone, Aaron; Peugeot, Christophe

    2014-01-01

    Within the framework of the African Monsoon Multidisciplinary Analysis (AMMA) Land Surface Model Intercomparison Project phase 2 (ALMIP-2), this study evaluates the water balance simulated by the Interactions between Soil, Biosphere, and Atmosphere (ISBA) over the upper Oum River basin, in Benin, using a mesoscale river routing scheme (RRS). The RRS is based on the nonlinear Muskingum Cunge method coupled with two linear reservoirs that simulate the time delay of both surface runoff and base flow that are produced by land surface models. On the basis of the evidence of a deep water-table recharge in that region,a reservoir representing the deep-water infiltration (DWI) is introduced. The hydrological processes of the basin are simulated for the 2005-08 AMMA field campaign period during which rainfall and stream flow data were intensively collected over the study area. Optimal RRS parameter sets were determined for three optimization experiments that were performed using daily stream flow at five gauges within the basin. Results demonstrate that the RRS simulates stream flow at all gauges with relative errors varying from -22% to 3% and Nash-Sutcliffe coefficients varying from 0.62 to 0.90. DWI varies from 24% to 67% of the base flow as a function of the sub-basin. The relatively simple reservoir DWI approach is quite robust, and further improvements would likely necessitate more complex solutions (e.g., considering seasonality and soil type in ISBA); thus, such modifications are recommended for future studies. Although the evaluation shows that the simulated stream flows are generally satisfactory, further field investigations are necessary to confirm some of the model assumptions.

  7. Nanostructure sword-like ZnO wires: Rapid synthesis and characterization through a microwave-assisted route

    International Nuclear Information System (INIS)

    Kajbafvala, Amir; Shayegh, Mohammad Reza; Mazloumi, Mahyar; Zanganeh, Saeid; Lak, Aidin; Mohajerani, Matin Sadat; Sadrnezhaad, S.K.

    2009-01-01

    Nanostructure sword-like ZnO wires with diameters of about 80-250 nm and the length of ∼1-4 μm have been synthesized by a fast, simple and template-free microwave-assisted method. X-ray diffraction (XRD) analysis, scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared (FT-IR) spectroscopy and room temperature photoluminescence (PL) measurements was used for characterization of the as-prepared products. The nanostructure sword-like ZnO wires have high crystallinity with the average crystallite size of about 53 nm and show a UV emission and a visible green band in their PL spectrum. The possible growth mechanism of the nanostructures along the crystallographic direction and subsequent formation of wires were also investigated

  8. Template-assisted electrostatic spray deposition as a new route to mesoporous, macroporous, and hierarchically porous oxide films.

    Science.gov (United States)

    Sokolov, S; Paul, B; Ortel, E; Fischer, A; Kraehnert, R

    2011-03-01

    A novel film coating technique, template-assisted electrostatic spray deposition (TAESD), was developed for the synthesis of porous metal oxide films and tested on TiO(2). Organic templates are codeposited with the titania precursor by electrostatic spray deposition and then removed during calcination. Resultant films are highly porous with pores casted by uniformly sized templates, which introduced a new level of control over the pore morphology for the ESD method. Employing the amphiphilic block copolymer Pluronic P123, PMMA latex spheres, or a combination of the two, mesoporous, macroporous, and hierarchically porous TiO(2) films are obtained. Decoupled from other coating parameters, film thickness can be controlled by deposition time or depositing multiple layers while maintaining the coating's structure and integrity.

  9. A Comparison of Male and Female Assistant Superintendents and Their Descriptions of Internal Barriers, External Barriers, Motivators, Stressors, and Discriminatory Acts They Anticipate Encountering on the Route to the Superintendency

    Science.gov (United States)

    Hunter, Tanesha N.

    2013-01-01

    The purpose of this research study was to compare male and female assistant superintendents and their descriptions of Internal Barriers, External Barriers, Internal Motivators, External Motivators, Stressors, and Discriminatory Acts they anticipated encountering on the route to the superintendency in Suffolk and Nassau Counties on Long Island, New…

  10. Summary of routes for different study of combustion reaction in scale pilot magnetic nanocatalysts production Ni_0_,_5Zn_0_,_5Fe_2O_4

    International Nuclear Information System (INIS)

    Barros, Ana Beatriz de Sousa; Moura, Thales Filipe Barbosa de; Vasconcelos, Erik Vilar; Pereira, Kleberson Ricardo de Oliveira; Dantas, Joelda; Costa, Ana Cristina Figueiredo de Melo

    2016-01-01

    Biodiesel is derived from renewable sources and because of concerns about the environment, has gained relevance as regards the search for sustainable sources. It can be obtained by different processes consisting of a chemical reaction of vegetable oil or animal fat with a common alcohol, stimulated by a catalyst. In this work we used for the production of biodiesel the animal fat oil, beef tallow, because it’s a cheap raw material, avoiding discharges and pollution of the environment and considered to be a raw material clean. This study aimed to prepare a magnetic NiZn catalyst, wherein the synthesis was performed in two stainless steel containers with different capacity, PM and MM 10 and 30g / product by reacting, respectively, and characterized by XRD and EDX. The biodiesel was obtained by methyl esterification at 180 ° C / 1hrs, molar ratio 1:12, 2% catalys. Blank test was also conducted to compare the results. It was found that the two routes showed peaks of highest intensity corresponding to the cubic spinel crystalline phase majority of NiZn ferrite. The value of the crystallite size for the PM catalyst was higher by 23% compared to MM. The conversion into biodiesel results were approximately 62%, 42% and 5%, AM, and MM test blank respectively. So when comparing the blank test with PM and MM, the catalyst showed efficiency for the catalytic reaction, more effective for PM. (author)

  11. Optimization of RT-PCR reactions in studies with genes of lignin biosynthetic route in Saccharum spontaneum

    Directory of Open Access Journals (Sweden)

    JUAN P.P. LLERENA

    Full Text Available ABSTRACT Saccharum spontaneum has been used for the development of energy cane a crop aimed to be used for the production of second-generation ethanol, or lignocellulosic ethanol. Lignin is a main challenge in the conversion of cell wall sugars into ethanol. In our studies to isolate the genes the lignin biosynthesis in S. spontaneum we have had great difficulty in RT-PCR reactions. Thus, we evaluated the effectiveness of different additives in the amplification of these genes. While COMT and CCoAOMT genes did not need any additives for other genes there was no amplification (HCT, F5H, 4CL and CCR or the yield was very low (CAD and C4H. The application of supplementary cDNA was enough to overcome the non-specificity and low yield for C4H and C3H, while the addition of 0.04% BSA + 2% formamide was effective to amplify 4CL, CCR, F5H and CCR. HCT was amplified only by addition of 0.04% BSA + 2% formamide + 0.1 M trehalose and amplification of PAL was possible with addition of 2% of DMSO. Besides optimization of expression assays, the results show that additives can act independently or synergistically.

  12. Mg-doped biphasic calcium phosphate by a solid state reaction route: Characterization and evaluation of cytotoxicity

    Energy Technology Data Exchange (ETDEWEB)

    Webler, Geovana D. [Instituto de Física, Universidade Federal de Alagoas, Maceió-AL 57072970 (Brazil); Correia, Ana C.C.; Barreto, Emiliano [Laboratório de Biologia Celular, Universidade Federal de Alagoas, Maceió-AL 57072970 (Brazil); Fonseca, Eduardo J.S., E-mail: eduardo@fis.ufal.br [Instituto de Física, Universidade Federal de Alagoas, Maceió-AL 57072970 (Brazil)

    2015-07-15

    Hydroxyapatite (HAP) and β-tricalcium phosphate (β-TCP) are widely used in tissue engineering because of their chemical similarity to the inorganic bone phase. In this work, we prepare biphasic calcium phosphate (BCP, a mixture of HAP and β-TCP) doped with different concentrations of magnesium to investigate the influence of magnesium on the BCP crystal structure. Magnesium is known to be an important element in the composition of bones and teeth. Recent research has shown that the doping of magnesium into BCP improves its bone metabolism and mechanical properties without affecting its biocompatibility. The samples were prepared by solid-state reaction from calcium carbonate, monobasic ammonium phosphate, and magnesium nitrate hexahydrate. Varying concentrations of magnesium were used and its modifications were examined by different characterization techniques. The phase composition and morphology of the ceramic powders were characterized by X-ray diffraction and scanning electron microscopy, respectively. The functional groups were analyzed using Fourier transform infrared spectroscopy and Raman spectroscopy. Cell viability experiments, using macrophage-like cell lines J774, showed that the synthesized Mg-doped BCP did not exhibit cytotoxicity regardless of the doses assayed or the different concentrations of magnesium used, suggesting it as a good material for potential biological applications. - Highlights: • Simple and fast method for the preparation of the Mg-BCP. • Study of the influence of the incorporation of Mg in the BCP. • Cell viability showed that the synthesized Mg-BCP did not exhibit cytotoxicity.

  13. Mg-doped biphasic calcium phosphate by a solid state reaction route: Characterization and evaluation of cytotoxicity

    International Nuclear Information System (INIS)

    Webler, Geovana D.; Correia, Ana C.C.; Barreto, Emiliano; Fonseca, Eduardo J.S.

    2015-01-01

    Hydroxyapatite (HAP) and β-tricalcium phosphate (β-TCP) are widely used in tissue engineering because of their chemical similarity to the inorganic bone phase. In this work, we prepare biphasic calcium phosphate (BCP, a mixture of HAP and β-TCP) doped with different concentrations of magnesium to investigate the influence of magnesium on the BCP crystal structure. Magnesium is known to be an important element in the composition of bones and teeth. Recent research has shown that the doping of magnesium into BCP improves its bone metabolism and mechanical properties without affecting its biocompatibility. The samples were prepared by solid-state reaction from calcium carbonate, monobasic ammonium phosphate, and magnesium nitrate hexahydrate. Varying concentrations of magnesium were used and its modifications were examined by different characterization techniques. The phase composition and morphology of the ceramic powders were characterized by X-ray diffraction and scanning electron microscopy, respectively. The functional groups were analyzed using Fourier transform infrared spectroscopy and Raman spectroscopy. Cell viability experiments, using macrophage-like cell lines J774, showed that the synthesized Mg-doped BCP did not exhibit cytotoxicity regardless of the doses assayed or the different concentrations of magnesium used, suggesting it as a good material for potential biological applications. - Highlights: • Simple and fast method for the preparation of the Mg-BCP. • Study of the influence of the incorporation of Mg in the BCP. • Cell viability showed that the synthesized Mg-BCP did not exhibit cytotoxicity

  14. Microwave-assisted intramolecular dehydrogenative Diels-Alder reactions for the synthesis of functionalized naphthalenes/solvatochromic dyes.

    Science.gov (United States)

    Kocsis, Laura S; Benedetti, Erica; Brummond, Kay M

    2013-04-01

    Functionalized naphthalenes have applications in a variety of research fields ranging from the synthesis of natural or biologically active molecules to the preparation of new organic dyes. Although numerous strategies have been reported to access naphthalene scaffolds, many procedures still present limitations in terms of incorporating functionality, which in turn narrows the range of available substrates. The development of versatile methods for direct access to substituted naphthalenes is therefore highly desirable. The Diels-Alder (DA) cycloaddition reaction is a powerful and attractive method for the formation of saturated and unsaturated ring systems from readily available starting materials. A new microwave-assisted intramolecular dehydrogenative DA reaction of styrenyl derivatives described herein generates a variety of functionalized cyclopenta[b]naphthalenes that could not be prepared using existing synthetic methods. When compared to conventional heating, microwave irradiation accelerates reaction rates, enhances yields, and limits the formation of undesired byproducts. The utility of this protocol is further demonstrated by the conversion of a DA cycloadduct into a novel solvatochromic fluorescent dye via a Buchwald-Hartwig palladium-catalyzed cross-coupling reaction. Fluorescence spectroscopy, as an informative and sensitive analytical technique, plays a key role in research fields including environmental science, medicine, pharmacology, and cellular biology. Access to a variety of new organic fluorophores provided by the microwave-assisted dehydrogenative DA reaction allows for further advancement in these fields.

  15. Microwave-assisted flow processing in heterogeneously copper nano-catalyzed reactions

    NARCIS (Netherlands)

    Benaskar, F.

    2012-01-01

    In the last decades, micro-processing and microwave technology have been established as mature technologies, however, mainly instigated by academia. Many advances in micro-process technology have led to novel routes and/or process windows to replace batch operations by more efficient continuous

  16. Comparison of postoperative pain and inflammation reaction in dogs undergoing preventive laparoscopic-assisted and incisional gastropexy

    OpenAIRE

    HARAGUCHI, Tomoya; KIMURA, Shiho; ITOH, Harumichi; NISHIKAWA, Shimpei; HIYAMA, Masato; TANI, Kenji; ISERI, Toshie; ITOH, Yoshiki; NAKAICHI, Munekazu; TAURA, Yasuho; ITAMOTO, Kazuhito

    2017-01-01

    This study compared the effects of postoperative pain and inflammation reaction after preventive laparoscopic-assisted gastropexy (LAG) and incisional gastropexy (IG) in 10 clinically normal Beagles. Surgical time, incision length, visual analog scale (VAS) score, University of Melbourne Pain Scale (UMPS) score, and plasma C-reactive protein (CRP), plasma cortisol (COR), and serum interleukin-6 (IL-6) levels were evaluated. The VAS and UMPS scores and COR and IL-6 levels were recorded at 0.5,...

  17. Nano-sized Fe-metal catalyst on ZnO-SiO2: (photo-assisted deposition and impregnation) Synthesis routes and nanostructure characterization

    International Nuclear Information System (INIS)

    Mohamed, R.M.; Al-Rayyani, M.A.; Baeissa, E.S.; Mkhalid, I.A.

    2011-01-01

    Highlights: → We prepared Fe/ZnO-SiO 2 by two methods. → We tested photocatalytic activity for degradation of methylene blue dye. → We controlled band gap and size. → We found activity of Fe/ZnO-SiO 2 prepared by PAD is hightest photocatalytic activity. - Abstract: A nano-sized Fe metal on ZnO-SiO 2 was synthesized using the photo-assisted deposition (PAD) and impregnation routes. The obtained samples were characterized by a series of techniques including X-ray diffraction (XRD), UV-vis diffuse reflectance spectroscopy, N 2 adsorption, extended X-ray absorption fine structure (EXAFS), and transmission electron microscopy (TEM). Photocatalytic reactivity using Fe-ZnO-SiO 2 catalysts under visible-light condition on the degradation of methylene blue dye was evaluated. The results of characterization reveal, a notable photocatalytic activity of PAD:Fe-ZnO-SiO 2 which was about 9 and 12 times higher than that of Img:Fe-ZnO-SiO 2 and ZnO-SiO 2 , respectively.

  18. Rapid synthesis of water-dispersible superparamagnetic iron oxide nanoparticles by a microwave-assisted route for safe labeling of endothelial progenitor cells.

    Science.gov (United States)

    Carenza, Elisa; Barceló, Verónica; Morancho, Anna; Montaner, Joan; Rosell, Anna; Roig, Anna

    2014-08-01

    We synthesize highly crystalline citrate-coated iron oxide superparamagnetic nanoparticles that are stable and readily dispersible in water by an extremely fast microwave-assisted route and investigate the uptake of magnetic nanoparticles by endothelial cells. Nanoparticles form large aggregates when added to complete endothelial cell medium. The size of the aggregates was controlled by adjusting the ionic strength of the medium. The internalization of nanoparticles into endothelial cells was then investigated by transmission electron microscopy, magnetometry and chemical analysis, together with cell viability assays. Interestingly, a sevenfold more efficient uptake was found for systems with larger nanoparticle aggregates, which also showed significantly higher magnetic resonance imaging effectiveness without compromising cell viability and functionality. We are thus presenting an example of a straightforward microwave synthesis of citrate-coated iron oxide nanoparticles for safe endothelial progenitor cell labeling and good magnetic resonance cell imaging with potential application for magnetic cell guidance and in vivo cell tracking. Copyright © 2014 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  19. Duplex-assisted carotid artery stenting without administration of contrast medium for patients with chronic kidney disease or allergic reaction.

    Science.gov (United States)

    Mizowaki, Takashi; Fujita, Atsushi; Imahori, Taichiro; Uyama, Atsushi; Inoue, Satoshi; Kohta, Masaaki; Hamaguchi, Hirotoshi; Sasayama, Takashi; Hosoda, Kohkichi; Kohmura, Eiji

    2016-07-01

    We aimed to investigate the safety and feasibility of duplex-assisted carotid artery stenting (CAS) without administration of contrast medium for the prevention of adverse reactions. Fifteen patients (9 % of all CASs) with severe carotid stenosis (≥70 %) associated with chronic kidney disease (CKD) (stage ≥3) or allergy to contrast medium underwent duplex-assisted CAS without administration of contrast medium over 4 years. The procedural success rate and perioperative complication rates were compared between the duplex-assisted CAS (n = 15) and conventional CAS (n = 153) groups. The technical success rate was 100 % in both groups. Combined stroke or death rates during the post-procedural period did not differ significantly between the duplex-assisted CAS group (0/15, 0 %) and conventional CAS group (4/153, 2.6 %). None of the 14 patients with CKD in the duplex-assisted CAS group experienced further deterioration of renal function. The mean surface radiation dose of participants in the duplex-assisted CAS group (n = 13, 312 ± 131 mGy) was significantly lower than that of the conventional CAS group (n = 31, 1036 ± 571 mGy) (p duplex-assisted CAS group (156 ± 39.7 min) and the conventional CAS group (156 ± 37.4 min). Duplex-assisted CAS without administration of contrast medium could be an alternative option in selected patients deemed to be at high risk for renal failure from nephrotoxic contrast medium or who have an allergy to contrast medium.

  20. Comparison of TiO2 photocatalysis, electrochemically assisted Fenton reaction and direct electrochemistry for simulation of phase I metabolism reactions of drugs.

    Science.gov (United States)

    Ruokolainen, Miina; Gul, Turan; Permentier, Hjalmar; Sikanen, Tiina; Kostiainen, Risto; Kotiaho, Tapio

    2016-02-15

    The feasibility of titanium dioxide (TiO2) photocatalysis, electrochemically assisted Fenton reaction (EC-Fenton) and direct electrochemical oxidation (EC) for simulation of phase I metabolism of drugs was studied by comparing the reaction products of buspirone, promazine, testosterone and 7-ethoxycoumarin with phase I metabolites of the same compounds produced in vitro by human liver microsomes (HLM). Reaction products were analysed by UHPLC-MS. TiO2 photocatalysis simulated the in vitro phase I metabolism in HLM more comprehensively than did EC-Fenton or EC. Even though TiO2 photocatalysis, EC-Fenton and EC do not allow comprehensive prediction of phase I metabolism, all three methods produce several important metabolites without the need for demanding purification steps to remove the biological matrix. Importantly, TiO2 photocatalysis produces aliphatic and aromatic hydroxylation products where direct EC fails. Furthermore, TiO2 photocatalysis is an extremely rapid, simple and inexpensive way to generate oxidation products in a clean matrix and the reaction can be simply initiated and quenched by switching the UV lamp on/off. Copyright © 2015 Elsevier B.V. All rights reserved.

  1. Mechanisms for the inversion of chirality: Global reaction route mapping of stereochemical pathways in a probable chiral extraterrestrial molecule, 2-aminopropionitrile

    International Nuclear Information System (INIS)

    Kaur, Ramanpreet; Vikas

    2015-01-01

    2-Aminopropionitrile (APN), a probable candidate as a chiral astrophysical molecule, is a precursor to amino-acid alanine. Stereochemical pathways in 2-APN are explored using Global Reaction Route Mapping (GRRM) method employing high-level quantum-mechanical computations. Besides predicting the conventional mechanism for chiral inversion that proceeds through an achiral intermediate, a counterintuitive flipping mechanism is revealed for 2-APN through chiral intermediates explored using the GRRM. The feasibility of the proposed stereochemical pathways, in terms of the Gibbs free-energy change, is analyzed at the temperature conditions akin to the interstellar medium. Notably, the stereoinversion in 2-APN is observed to be more feasible than the dissociation of 2-APN and intermediates involved along the stereochemical pathways, and the flipping barrier is observed to be as low as 3.68 kJ/mol along one of the pathways. The pathways proposed for the inversion of chirality in 2-APN may provide significant insight into the extraterrestrial origin of life

  2. A microwave assisted one-pot route synthesis of bimetallic PtPd alloy cubic nanocomposites and their catalytic reduction for 4-nitrophenol

    Science.gov (United States)

    Zhang, Jian; Gan, Wei; Fu, Xucheng; Hao, Hequn

    2017-10-01

    We herein report a simple, rapid, and eco-friendly chemical route to the one-pot synthesis of bimetallic PtPd alloy cubic nanocomposites under microwave irradiation. During this process, water was employed as an environmentally benign solvent, while dimethylformamide served as a mild reducing agent, and polyvinylpyrrolidone was used as both a dispersant and a stabilizer. The structure, morphology, and composition of the resulting alloy nanocomposites were examined by x-ray diffraction, transmission electron microscopy, and energy dispersive x-ray spectroscopy. A detailed study was then carried out into the catalytic activity of the PtPd nanocomposites with a Pt:Pd molar ratio of 50:50 in the reduction of 4-nitrophenol (4-NP) by sodium borohydride as a model reaction. Compared with pristine Pt and Pd monometallic nanoparticles (PtNPs and PdNPs), the bimetallic PtPd alloy nanocomposites exhibited enhanced catalytic activities and were readily recyclable in the reduction of 4-NP due to synergistic effects.

  3. A Self-Propagating Foaming Process of Porous Al-Ni Intermetallics Assisted by Combustion Reactions

    Directory of Open Access Journals (Sweden)

    Makoto Kobashi

    2009-12-01

    Full Text Available The self-propagating foaming process of porous Al-Ni intermetallics was investigated. Aluminum and nickel powders were blended, and titanium and boron carbide powders were added as reactive exothermic agents. The blended powder was extruded to make a rod-shape precursor. Only one end of the rod precursor was heated to ignite the reaction. The reaction propagated spontaneously throughout the precursor. Pore formation took place at the same time as the reaction occurred. Adding the exothermic agent was effective to increase the porosity. Preheating the precursor before the ignition was also very effective to produce porous Al-Ni intermetallics with high porosity.

  4. Microwave-assisted Maillard reactions for the preparation of advanced glycation end products (AGEs).

    Science.gov (United States)

    Visentin, Sonja; Medana, Claudio; Barge, Alessandro; Giancotti, Valeria; Cravotto, Giancarlo

    2010-05-21

    The application of microwaves as an efficient form of volumetric heating to promote organic reactions was recognized in the mid-1980 s. It has a much longer history in the food research and industry where microwave irradiation was studied in depth to optimize food browning and the development of desirable flavours from Maillard reactions. The microwave-promoted Maillard reaction is a challenging synthetic method to generate molecular diversity in a straightforward way. In this paper we present a new rapid and efficient one-pot procedure for the preparation of pentosidine and other AGEs under microwave irradiation.

  5. Optimization of the production of ethyl esters by ultrasound assisted reaction of soybean oil and ethanol

    OpenAIRE

    Rodrigues,S.; Mazzone,L. C. A.; Santos,F. F. P.; Cruz,M. G. A.; Fernandes,F. A. N.

    2009-01-01

    Biodiesel is a renewable liquid fuel that can be produced by a transesterification reaction between a vegetable oil and an alcohol. This paper evaluates and optimizes the production of ethyl esters (biodiesel) from soybean oil and ethanol. The reaction was carried out by applying ultrasound under atmospheric pressure and ambient temperature. Response surface methodology was used to evaluate the influence of alcohol to oil molar ratio and catalyst concentration on the yield of conversion of so...

  6. Microwave Assisted Condensation Reactions of 2-Aryl Hydrazonopropanals with Nucleophilic Reagents and Dimethyl Acetylenedicarboxylate

    Directory of Open Access Journals (Sweden)

    Rita M. Borik

    2007-08-01

    Full Text Available The reaction of methyl ketones 1a-g with dimethylformamide dimethylacetal (DMFDMA afforded the enaminones 2a-g, which were coupled with diazotized aromatic amines 3a,b to give the corresponding aryl hydrazones 6a-h. Condensation of compounds 6a-h with some aromatic heterocyclic amines afforded iminoarylhydrazones 9a-m. Enaminoazo compounds 12a,b could be obtained from condensation of 6c with secondary amines. The reaction of 6e,h with benzotriazolylacetone yielded 14a,b. Also, the reaction of 6a,b,d-f,h with glycine and hippuric acid in acetic anhydride afforded pyridazinone derivatives 17a-f. Synthesis of pyridazine carboxylic acid derivatives 22a,b from the reaction of 6b,e with dimethyl acetylenedicarboxylate (DMAD in the presence of triphenylphosphine at room temperature is also reported. Most of these reactions were conducted under irradiation in a microwave oven in the absence of solvent in an attempt to improve the product yields and to reduce the reaction times.

  7. Synthesis of S/Cr doped mesoporous TiO2 with high-active visible light degradation property via solid state reaction route

    International Nuclear Information System (INIS)

    Liu Shaoyou; Tang Qunli; Feng Qingge

    2011-01-01

    S/Cr doped mesoporous TiO 2 (S-TiO 2 , Cr-TiO 2 , S-Cr-TiO 2 ) were successfully synthesized via a simple, effective and environmental benign solid state reaction route. The low angle XRD patterns demonstrated that the resulting samples possess mesostructures. The further characterizations via N 2 adsorption-desorption and XPS showed that the typical S/Cr co-doped mesoporous TiO 2 (S-Cr-TiO 2 (5S-5Cr)) possesses mesopore with the high specific surface area of 118.4 m 2 /g and narrow pore size distribution, and both S and Cr have been incorporated into the lattice of TiO 2 with the amounts of 4.16% sulfur and 7.88% chromium, respectively. And Raman spectroscopy shows that the surface of S-Cr-TiO 2 (5S-5Cr) material possesses stretching vibrational peaks at ∼709, ∼793 cm -1 are assignable to the Ti-O-Cr, O-Cr (Ti)-OH bonds, respectively. Interestingly, the UV-vis displayed that the absorption regions of S/Cr doped mesoporous TiO 2 cover the visible light region. As for the series of S-Cr-TiO 2 samples, the absorption region even extends to near infrared region with strong adsorption. Moreover, compared with the pure titanium dioxide (P25-TiO 2 ), the photodegradation properties of bromocresol green (BCG) on the S/Cr doped mesoporous TiO 2 showed excellent photocatalytic properties under visible light irradiation. Within 50 min visible light irradiation, 82.6% of the initial BCG was degraded for the S-Cr-TiO 2 (6S-4Cr) photocatalyst.

  8. Ultrasound-assisted self-metathesis reactions of monounsaturated fatty acids

    Directory of Open Access Journals (Sweden)

    Elmkaddem Mohammed Kamal

    2016-09-01

    Full Text Available An efficient protocol for the self-metathesis of oleic acid, using ruthenium catalysts is described. The self-metathesis reaction under ultrasonic activation allows the conversion of monoenic fatty acids such as oleic acid, elaidic acid and erucic acid into diacids and olefins with very short reaction times in the presence of Grubbs ruthenium catalysts. These yields and selectivity towards the desired products are influenced by the nature of solvents. This study demonstrated that metathesis reaction carried out in DCM or 1-butanol showed promising results, since it produced a variety of products, like n-alkenes and diacids with good yields (45–75% and high selectivities (75–95%.

  9. Optimization of the production of ethyl esters by ultrasound assisted reaction of soybean oil and ethanol

    Directory of Open Access Journals (Sweden)

    S. Rodrigues

    2009-06-01

    Full Text Available Biodiesel is a renewable liquid fuel that can be produced by a transesterification reaction between a vegetable oil and an alcohol. This paper evaluates and optimizes the production of ethyl esters (biodiesel from soybean oil and ethanol. The reaction was carried out by applying ultrasound under atmospheric pressure and ambient temperature. Response surface methodology was used to evaluate the influence of alcohol to oil molar ratio and catalyst concentration on the yield of conversion of soybean oil into ethyl esters. The process resulted in a maximum yield of 91.8% after 30 minutes of reaction. The process variables alcohol to oil ratio and catalyst to oil ratio were statistically significant regarding the yield of ethyl esters. The optimal operating condition was obtained applying an alcohol to oil molar ratio of 10.2 and a catalyst to oil weight ratio of 0.0035.

  10. Pyridine group assisted addition of diazo-compounds to imines in the 3-CC reaction of 2-aminopyridines, aldehydes, and diazo-compounds.

    Science.gov (United States)

    Gulevich, Anton V; Helan, Victoria; Wink, Donald J; Gevorgyan, Vladimir

    2013-02-15

    A novel three-component coupling (3-CC) reaction of 2-aminoazines, aromatic aldehydes, and diazo-compounds producing polyfunctional β-amino-α-diazo-compounds has been developed. The reaction features an unprecedented heterocycle-assisted addition of a diazo-compound to an imine. The obtained diazoesters were efficiently converted into valuable heterocycles as well as β-amino acid derivatives.

  11. Reaction

    African Journals Online (AJOL)

    abp

    19 oct. 2017 ... Reaction to Mohamed Said Nakhli et al. concerning the article: "When the axillary block remains the only alternative in a 5 year old child". .... Bertini L1, Savoia G, De Nicola A, Ivani G, Gravino E, Albani A et al ... 2010;7(2):101-.

  12. Microwave-Assisted Organic Synthesis Using Benign Reaction Medium and Reagents

    Science.gov (United States)

    Account of chemical reactions expedited by microwave (MW) exposure of neat reactants for the rapid one-pot assembly of heterocyclic compounds from in situ generated reactive intermediates via enamines or using hypervalent iodine reagents will be described that can be adapted for ...

  13. Shock-Induced and Shock-Assisted Reaction Synthesis of Materials

    National Research Council Canada - National Science Library

    Thadhani, N. N

    1997-01-01

    The beneficial effects of shock-compression of powders and solid-state chemical reactions were utilized to synthesize Ti-Si and Ti-A1 intermetallics, Ti-B and Ti-C ceramics, and Ti-Si:Ti-A1 composites...

  14. Anomalous Hall effect assisted by interfacial chemical reaction in perpendicular Co/Pt multilayers

    Science.gov (United States)

    Liu, Qian; Jiang, Shaolong; Teng, Jiao

    2018-05-01

    To uncover the underlying mechanism of Mg effect on the improved anomalous Hall effect (AHE) of perpendicular [Pt/Co]3/Mg/HfO2 multilayers, the X-ray photoelectron spectroscopy analysis has been carried out. It is found that Mg interlayer at the Co/HfO2 interface could prevent the Co oxidation to some extent via interfacial chemical reaction. As a result, A large anomalous Hall resistivity (ρAH) is obtained in perpendicular [Pt/Co]3/Mg/HfO2 multilayers, with a maximum ρAH of 3.02 μΩ cm, which is 59% larger than that in Co/Pt multilayers without Mg insertion. This effective modification of the AHE based on interfacial chemical reaction provides a promising pathway for spintronic applications.

  15. Cu{sub 2}ZnSnS{sub 4} thin films by simple replacement reaction route for solar photovoltaic application

    Energy Technology Data Exchange (ETDEWEB)

    Tiwari, Devendra, E-mail: devendratiwari.rnd@ecchanga.ac.in [Dr. K. C. Patel Research and Development Centre, Charotar University of Science and Technology, Changa, Anand District, Gujarat 388421 (India); Chaudhuri, Tapas K. [Dr. K. C. Patel Research and Development Centre, Charotar University of Science and Technology, Changa, Anand District, Gujarat 388421 (India); Ray, Arabinda [P. D. Patel Institute of Applied Sciences, Charotar University of Science and Technology, Changa, Anand District, Gujarat 388421 (India); Tiwari, Krishan Dutt [Powerdeal Energy Systems - India, Private Limited, Nashik 422010, Maharashtra (India)

    2014-01-31

    A process for deposition of Cu{sub 2}ZnSnS{sub 4} (CZTS) films using replacement of Zn{sup 2+} in ZnS is demonstrated. X-ray diffraction pattern and Raman spectroscopy confirm the formation of pure CZTS. Atomic force microscopy shows the films to be homogeneous and compact with root mean squared roughness of 6 nm. The direct band gap of CZTS films as elucidated by UV–Vis-NIR spectroscopy is 1.45 eV. The CZTS films exhibit p-type conduction with electrical conductivity of 4.6 S/cm. The hole concentration and hole mobility is determined to be 3.6 × 10{sup 17} cm{sup −3} and 1.4 cm{sup 2}V{sup −1} s{sup −1} respectively. Solar cells with structure: graphite/CZTS/CdS/ZnO/SnO{sub 2}:In/Soda lime glass are also fabricated, gave photo-conversion efficiency of 6.17% with open circuit voltage and short circuit current density of 521 mV and 19.13 mA/cm{sup 2}, respectively and a high fill factor of 0.62. The external quantum efficiency of the solar cell lies above 60% in the visible region. - Highlights: • Pure kesterite Cu{sub 2}ZnSnS{sub 4} thin films deposited by replacement reaction route • Energy band gap of films is 1.45 eV. • p-type films with conductivity of 4.6 S/cm and mobility of 1.4 cm{sup 2} S{sup −1} V{sup −1} • Fabrication of Graphite/Cu{sub 2}ZnSnS{sub 4}/CdS/ZnO/SnO{sub 2}:In/Glass solar cell • Solar cell delivered efficiency of 6.17% with high fill factor of 0.62.

  16. Aqueous microwaves assisted cross-coupling reactions applied to unprotected nucleosides.

    Directory of Open Access Journals (Sweden)

    CHRISTOPHE eLEN

    2015-02-01

    Full Text Available Nucleoside analogues have attracted much attention due to their potential biological activities. Amongst all synthetic nucleosides, C5-modified pyrimidines and C7- or C8-modified purines have mostly been prepared using palladium cross-coupling reactions and then studied as antitumoral and antiviral agents. Our objective is to focus this review on the Suzuki-Miyaura and on the Heck cross-couplings of nucleosides using microwave irradiations which are an alternative technology compatible with green chemistry and sustainable development.

  17. Synthesis of aqueous ferrofluids of ZnxFe3−xO4 nanoparticles by citric acid assisted hydrothermal-reduction route for magnetic hyperthermia applications

    International Nuclear Information System (INIS)

    Behdadfar, Behshid; Kermanpur, Ahmad; Sadeghi-Aliabadi, Hojjat; Morales, Maria del Puerto; Mozaffari, Morteza

    2012-01-01

    Superparamagnetic and monodispersed aqueous ferrofluids of Zn substituted magnetite nanoparticles (Zn x Fe 3−x O 4 , x=0, 0.25, 0.3, 0.37 and 0.4) were synthesized via hydrothermal-reduction route in the presence of citric acid, which is a facile, low energy and environmental friendly method. The synthesized nanoparticles were characterized by X ray diffraction (XRD) analysis, Fourier transform infrared (FTIR) spectroscopy, scanning and transmission electron microscopy (SEM and TEM) and the dynamic light scattering (DLS) method. The results showed that a certain amount of citric acid was required to obtain single phase Zn substituted magnetite nanoparticles. Citric acid acted as a modulator and reducing agent in the formation of spinel structure and controlled nanoparticle size and crystallinity. Mean particle sizes of the prepared nanoparticles were around 10 nm. The results that are obtained from XRD, magnetic and power loss measurements showed that the crystallinity, saturation magnetization (M S ) and loss power of the synthesized ferrofluids were all influenced by the substitution of Zn in the structure of magnetite. The Zn substituted magnetite nanoparticles obtained by this route showed a good stability in aqueous medium (pH 7) and hydrodynamic sizes below 100 nm and polydispersity indexes below 0.2. The calculated intrinsic loss power (ILP) for the sample x=0.3 (e.g. 2.36 nH m 2 /kg) was comparable to ILP of commercial ferrofluids with similar hydrodynamic sizes. - Highlights: ► We synthesized Zn substituted magnetite nanoparticles via hydrothermal-reduction route. ► We used citric acid as a reducing agent in this route. ► This route is a facile, low energy and environmental friendly method. ► The nanoparticles obtained by this route were superparamagnetic and stable in water. ► The calculated intrinsic loss power for the sample x=0.3 was 2.36 nH m 2 /kg.

  18. Comparison of postoperative pain and inflammation reaction in dogs undergoing preventive laparoscopic-assisted and incisional gastropexy.

    Science.gov (United States)

    Haraguchi, Tomoya; Kimura, Shiho; Itoh, Harumichi; Nishikawa, Shimpei; Hiyama, Masato; Tani, Kenji; Iseri, Toshie; Itoh, Yoshiki; Nakaichi, Munekazu; Taura, Yasuho; Itamoto, Kazuhito

    2017-09-12

    This study compared the effects of postoperative pain and inflammation reaction after preventive laparoscopic-assisted gastropexy (LAG) and incisional gastropexy (IG) in 10 clinically normal Beagles. Surgical time, incision length, visual analog scale (VAS) score, University of Melbourne Pain Scale (UMPS) score, and plasma C-reactive protein (CRP), plasma cortisol (COR), and serum interleukin-6 (IL-6) levels were evaluated. The VAS and UMPS scores and COR and IL-6 levels were recorded at 0.5, 1, 2, 4, 8, 12, 18 and 24 hr after surgery. CRP level was recorded at 12, 24 and 48 hr after surgery. The VAS and UMPS scores showed no significant intergroup differences. Compared to IG, LAG had significantly lower surgical time (45 ± 9.91 min vs 64 ± 5.30 min; Pgastric dilatation-volvulus. Nevertheless, since this study used experimental models, its usefulness should be evaluated in future cases.

  19. TCE degradation in groundwater by chelators-assisted Fenton-like reaction of magnetite: Sand columns demonstration.

    Science.gov (United States)

    Jia, Daqing; Sun, Sheng-Peng; Wu, Zhangxiong; Wang, Na; Jin, Yaoyao; Dong, Weiyang; Chen, Xiao Dong; Ke, Qiang

    2018-03-15

    Trichloroethylene (TCE) degradation in sand columns has been investigated to evaluate the potential of chelates-enhanced Fenton-like reaction with magnetite as iron source for in situ treatment of TCE-contaminated groundwater. The results showed that successful degradation of TCE in sand columns was obtained by nitrilotriacetic acid (NTA)-assisted Fenton-like reaction of magnetite. Addition of ethylenediaminedisuccinic acid (EDDS) resulted in an inhibitory effect on TCE degradation in sand columns. Similar to EDDS, addition of ethylenediaminetetraacetic acid (EDTA) also led to an inhibition of TCE degradation in sand column with small content of magnetite (0.5 w.t.%), but enhanced TCE degradation in sand column with high content of magnetite (7.0 w.t.%). Additionally, the presence of NTA, EDDS and EDTA greatly decreased H 2 O 2 uptake in sand columns due to the competition between chelates and H 2 O 2 for surface sites on magnetite (and sand). Furthermore, the presented results show that magnetite in sand columns remained stable in a long period operation of 230 days without significant loss of performance in terms of TCE degradation and H 2 O 2 uptake. Moreover, it was found that TCE was degraded mainly to formic acid and chloride ion, and the formation of chlorinated organic intermediates was minimal by this process. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Solar thermal polymerase chain reaction for smartphone-assisted molecular diagnostics

    Science.gov (United States)

    Jiang, Li; Mancuso, Matthew; Lu, Zhengda; Akar, Gunkut; Cesarman, Ethel; Erickson, David

    2014-02-01

    Nucleic acid-based diagnostic techniques such as polymerase chain reaction (PCR) are used extensively in medical diagnostics due to their high sensitivity, specificity and quantification capability. In settings with limited infrastructure and unreliable electricity, however, access to such devices is often limited due to the highly specialized and energy-intensive nature of the thermal cycling process required for nucleic acid amplification. Here we integrate solar heating with microfluidics to eliminate thermal cycling power requirements as well as create a simple device infrastructure for PCR. Tests are completed in less than 30 min, and power consumption is reduced to 80 mW, enabling a standard 5.5 Wh iPhone battery to provide 70 h of power to this system. Additionally, we demonstrate a complete sample-to-answer diagnostic strategy by analyzing human skin biopsies infected with Kaposi's Sarcoma herpesvirus (KSHV/HHV-8) through the combination of solar thermal PCR, HotSHOT DNA extraction and smartphone-based fluorescence detection. We believe that exploiting the ubiquity of solar thermal energy as demonstrated here could facilitate broad availability of nucleic acid-based diagnostics in resource-limited areas.

  1. Pyridine Group-Assisted Addition of Diazo-Compounds to Imines in the 3-CC Reaction of 2-Aminopyridines, Aldehydes, and Diazo-Compounds

    Science.gov (United States)

    Gulevich, Anton V.; Helan, Victoria; Wink, Donald J.

    2013-01-01

    A novel three-component (3-CC) coupling reaction of 2-aminoazines, aromatic aldehydes and diazo-compounds producing polyfunctional β-amino-α-diazo-compounds has been developed. The reaction features an unprecedented heterocycle-assisted addition of a diazo-compound to an imine. The obtained diazoesters were efficiently converted into valuable heterocycles, as well as to β-amino acid derivatives. PMID:23373731

  2. CATALYST-FREE REACTIONS UNDER SOLVENT-FEE CONDITIONS: MICROWAVE-ASSISTED SYNTHESIS OF HETEROCYCLIC HYDRAZONES BELOW THE MELTING POINT OF NEAT REACTANTS: JOURNAL ARTICLE

    Science.gov (United States)

    NRMRL-CIN-1437 Jeselnik, M., Varma*, R.S., Polanc, S., and Kocevar, M. Catalyst-free Reactions under Solvent-fee Conditions: Microwave-assisted Synthesis of Heterocyclic Hydrazones below the Melting Point of Neat Reactants. Published in: Chemical Communications 18:1716-1717 (200...

  3. A simple fast microwave-assisted synthesis of thermoelectric bismuth telluride nanoparticles from homogeneous reaction-mixture

    Energy Technology Data Exchange (ETDEWEB)

    Pradhan, Susmita [Jadavpur University, Department of Instrumentation Science (India); Das, Rashmita [Jadavpur University, Department of Instrumentation and Electronics Engineering (India); Bhar, Radhaballabh [Jadavpur University, Department of Instrumentation Science (India); Bandyopadhyay, Rajib [Jadavpur University, Department of Instrumentation and Electronics Engineering (India); Pramanik, Panchanan, E-mail: pramanik1946@gmail.com [GLA University, Department of Chemistry and Nanoscience (India)

    2017-02-15

    A new simple chemical method for synthesis of nanocrystalline bismuth telluride (Bi{sub 2}Te{sub 3}) has been developed by microwave assisted reduction of homogeneous tartrate complexes of bismuth and tellurium metal ions with hydrazine. The reaction is performed at pH 10. The nano-crystallites have rhombohedral phase identified by XRD. The size distribution of nanoparticle is narrow and it ranges between 50 to 70 nm. FESEM shows that the fine powders are composed of small crystallites. The TEM micrographs show mostly deformed spherical particles and the lattice fringes are found to be 0.137 nm. Energy dispersive X-ray spectroscopy (EDX) analysis shows the atomic composition ratio between bismuth and tellurium is 2:3. Thermoelectric properties of the materials are studied after sintering by spark plasma sintering method (SPS). The grain size of the material after sintering is in the nanometer range. The material shows enhanced Seebeck coefficient and electrical conductivity value at 300 K. The figure of merit is found to be 1.18 at 300 K.

  4. Preparation of CdS nanoparticels with spin-coating assisted successive ionic layer reaction and their photoelectrochemical properties

    Directory of Open Access Journals (Sweden)

    Bao SUN

    2017-10-01

    Full Text Available In order to settle the problems in the traditional SILAR method for CdS deposition, such as smaller particles and being difficult to enhance the sensitive layers, an improved spin-coating assisted successive ionic layer reaction method (S-SILR substituted for the traditional SILAR method is used to deposit the CdS nanocrystals. The comparison between the improved and traditional methods is studied after depositing the CdS nanocrystals onto the ZnO nanorod arrays with the two approaches. Different analysis methods, SEM, XRD, UV-vis and the transit photocurrent measurement are conducted to characterize the morphologies and structures of the samples, as well as investigating the light absorption properties, and the photoelectric conversion performance of the electrodes. The results indicate that the CdS nanocrystals photosensitive layers could be totally coated onto the ZnO nanorod arrays more easily by the improved S-SILR method; the light absorption properties and the photoelectric conversion performance of the electrodes prepared by the improved S-SILR method are more excellent compared with those electrodes prepared by the traditional SILAR method. The improvement of the CdS deposition method has certain guiding significance in enhancing the operability of the preparation technology and the photovoltaic performance of the solar cells.

  5. Asymmetric NHC-catalyzed aza-Diels-Alder reactions: Highly enantioselective route to α-amino acid derivatives and DFT calculations

    KAUST Repository

    Yang, Limin; Wang, Fei; Lee, Richmond; Lv, Yunbo; Huang, Kuo-Wei; Zhong, Guofu

    2014-01-01

    A facile N-heterocyclic carbene catalytic enantioselective aza-Diels-Alder reaction of oxodiazenes with α-chloroaldehydes as dienophile precursors is reported, with excellent enantioselectivity (ee > 99%) and excellent yield (up to 93%). DFT study

  6. A green route to methyl acrylate and acrylic acid by an aldol condensation reaction over H-ZSM-35 zeolite catalysts.

    Science.gov (United States)

    Ma, Zhanling; Ma, Xiangang; Liu, Hongchao; He, Yanli; Zhu, Wenliang; Guo, Xinwen; Liu, Zhongmin

    2017-08-10

    A one-step aldol condensation reaction to produce MA and AA is a green and promising strategy. Here, the aldol condensation reaction was first conducted with DMM and MAc over different types of zeolite catalysts. The H-ZSM-35 zeolite demonstrates excellent catalytic performance with a DMM conversion of 100% and a MA + AA selectivity of up to 86.2% and superior regeneration ability, with great potential for industrial operation.

  7. Arylation of beta, gamma-unsaturated lactones by a Heck-Matsuda reaction: an unexpected route to aryldiazene butenolides and pyridazinones

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, Jason G.; Correia, Carlos Roque D., E-mail: roque@iqm.unicamp.b [Universidade Estadual de Campinas (UNICAMP), SP (Brazil). Inst. de Quimica

    2010-07-01

    The palladium catalysed coupling of aryldiazonium salts with {beta}-{gamma}-unsaturated lactones under basic conditions has been investigated. Both (3H)-furanone and {alpha}-angelicalactone were evaluated as substrates in the Heck Matsuda reaction but both failed to afford the desired arylated butenolides. Under basic conditions, {beta}-{gamma}-unsaturated lactones generate highly nucleophilic enolates that preferentially undergo azo coupling reactions with arenediazonium salts to afford aryldiazene butenolides. The electronic and steric effect of the substituents on the aryldiazonium salt in the azo coupling reaction is described. Aryldiazene-lactone derivatives were obtained in good yields from a highly facile and straightforward procedure. An aminoisomaleimide was formed from (3H)-furanone and cyclized to the corresponding pyridazinones in modest yield. (author)

  8. Non-Enzymatic-Browning-Reaction: A Versatile Route for Production of Nitrogen-Doped Carbon Dots with Tunable Multicolor Luminescent Display

    Science.gov (United States)

    Wei, Weili; Xu, Can; Wu, Li; Wang, Jiasi; Ren, Jinsong; Qu, Xiaogang

    2014-01-01

    The non-enzymatic browning, namely Maillard reaction is commonly invoked to account for abiotic chemical transformations of organic matter. Here we report a new reaction pathway via the Maillard reaction to systematically synthesize a series of nitrogen-doped carbon dots (C-dots) with superhigh quantum yield (QY) and tunable multicolor luminescent displayment. The starting materials are glucose and the serial amino acid analogues which allow systemically controlling luminescent and physicochemical properties of C-dots at will. Unexpectedly, the as-prepared C-dots possess bright photoluminescence with QY up to 69.1% which is almost the highest ever reported, favorable biocompatibility, excellent aqueous and nonaqueous dispersibility, ultrahigh photostability, and readily functionalization. We have demonstrated that they are particularly suitable for multicolor luminescent display and long-term and real-time cellular imaging. Furthermore, the methodology is readily scalable to large yield, and can provide sufficient amount of C-dots for practical demands.

  9. Remote-controlled module-assisted synthesis of O-(2-[18F]fluoroethyl)-L-tyrosine as tumor PET tracer using two different radiochemical routes

    International Nuclear Information System (INIS)

    Wang Mingwei; Yin Duanzhi; Zhang Lan; Zhou Wei; Wang Yongxian

    2006-01-01

    The positron-emitter fluorine-18 labeled amino acid O-(2-[ 18 F]fluoroethyl)-L-tyrosine ([ 18 F]FET) has shown very promising perspectives for brain tumor diagnosis with positron emission tomography (PET). There have been two existing preparation routes of [ 18 F]FET named direct nucleophilic radiofiuorination of protected L-tyrosine and radiofiuoroallcylation of unprotected L-tyrosine, respectively. A general module was designed specifically for the routine synthesis of [ 18 F]FET, which could be suitable for the present two chemical methods with simple modifications. The fluorinated intermediates and the final product were separated and purified using solid phase extraction (SPE) on the Sep-Pak silica plus cartridge instead of the time-consuming high performance liquid chromatography (HPLC) procedures. The total synthesis time was about 50-60 rain with good radiochemical yield (about 20-40%, no-decay-corrected) and good radiochemical purity (more than 97%) for both the synthetic methods. (authors)

  10. 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.

  11. High Pressure Diels Alder Reactions of 1-Vinyl-2,2,6-trimethylcyclohexene Catalyzed by Chiral Lewis Acids; An Enantioselective Route to a Drimane Sesquiterpene Precursor.

    NARCIS (Netherlands)

    Knol, Joop; Meetsma, Auke; Feringa, Bernard

    1995-01-01

    The Diels Alder reaction of 1-vinyl-2,2,6-trimethylcyclohexene and 3-((E)-3-(methoxycarbonyl)propenoyl)-1,3-oxazolidin-2-one under high pressure, catalyzed by a chiral bis-imine copper(II) complex, yields a drimane sesquiterpene precursor in a highly regio- and diastereoselective manner with

  12. Near-infrared responsive PbS-sensitized photovoltaic photodetectors fabricated by the spin-assisted successive ionic layer adsorption and reaction method

    International Nuclear Information System (INIS)

    Im, Sang Hyuk; Kim, Hi-jung; Seok, Sang Il

    2011-01-01

    A PbS-sensitized photovoltaic photodetector responsive to near-infrared (NIR) light was fabricated by depositing monolayered PbS nanoparticles on a mesoporous TiO 2 (mp-TiO 2 ) film via the spin-assisted successive ionic layer adsorption and reaction (SILAR) method. By adjusting the size and morphology of the PbS nanoparticles through repeated spin-assisted SILAR cycles, the PbS-sensitized photovoltaic photodetector achieved an external quantum efficiency of 9.3% at 1140 nm wavelength and could process signals up to 1 kHz.

  13. Near-infrared responsive PbS-sensitized photovoltaic photodetectors fabricated by the spin-assisted successive ionic layer adsorption and reaction method

    Energy Technology Data Exchange (ETDEWEB)

    Im, Sang Hyuk; Kim, Hi-jung; Seok, Sang Il, E-mail: seoksi@krict.re.kr [KRICT-EPFL Global Research Laboratory, Advanced Materials Division, Korea Research Institute of Chemical Technology, 19 Sinseongno, Yuseong, Daejeon 305-600 (Korea, Republic of)

    2011-09-30

    A PbS-sensitized photovoltaic photodetector responsive to near-infrared (NIR) light was fabricated by depositing monolayered PbS nanoparticles on a mesoporous TiO{sub 2} (mp-TiO{sub 2}) film via the spin-assisted successive ionic layer adsorption and reaction (SILAR) method. By adjusting the size and morphology of the PbS nanoparticles through repeated spin-assisted SILAR cycles, the PbS-sensitized photovoltaic photodetector achieved an external quantum efficiency of 9.3% at 1140 nm wavelength and could process signals up to 1 kHz.

  14. The Azomethine Ylide Route to Amine C–H Functionalization: Redox-Versions of Classic Reactions and a Pathway to New Transformations

    Science.gov (United States)

    2016-01-01

    Conspectus Redox-neutral methods for the functionalization of amine α-C–H bonds are inherently efficient because they avoid external oxidants and reductants and often do not generate unwanted byproducts. However, most of the current methods for amine α-C–H bond functionalization are oxidative in nature. While the most efficient variants utilize atmospheric oxygen as the terminal oxidant, many such transformations require the use of expensive or toxic oxidants, often coupled with the need for transition metal catalysts. Redox-neutral amine α-functionalizations that involve intramolecular hydride transfer steps provide viable alternatives to certain oxidative reactions. These processes have been known for some time and are particularly well suited for tertiary amine substrates. A mechanistically distinct strategy for secondary amines has emerged only recently, despite sharing common features with a range of classic organic transformations. Among those are such widely used reactions as the Strecker, Mannich, Pictet–Spengler, and Kabachnik–Fields reactions, Friedel–Crafts alkylations, and iminium alkynylations. In these classic processes, condensation of a secondary amine with an aldehyde (or a ketone) typically leads to the formation of an intermediate iminium ion, which is subsequently attacked by a nucleophile. The corresponding redox-versions of these transformations utilize identical starting materials but incorporate an isomerization step that enables α-C–H bond functionalization. Intramolecular versions of these reactions include redox-neutral amine α-amination, α-oxygenation, and α-sulfenylation. In all cases, a reductive N-alkylation is effectively combined with an oxidative α-functionalization, generating water as the only byproduct. Reactions are promoted by simple carboxylic acids and in some cases require no additives. Azomethine ylides, dipolar species whose usage is predominantly in [3 + 2] cycloadditions and other pericyclic

  15. The azomethine ylide route to amine C-H functionalization: redox-versions of classic reactions and a pathway to new transformations.

    Science.gov (United States)

    Seidel, Daniel

    2015-02-17

    Conspectus Redox-neutral methods for the functionalization of amine α-C-H bonds are inherently efficient because they avoid external oxidants and reductants and often do not generate unwanted byproducts. However, most of the current methods for amine α-C-H bond functionalization are oxidative in nature. While the most efficient variants utilize atmospheric oxygen as the terminal oxidant, many such transformations require the use of expensive or toxic oxidants, often coupled with the need for transition metal catalysts. Redox-neutral amine α-functionalizations that involve intramolecular hydride transfer steps provide viable alternatives to certain oxidative reactions. These processes have been known for some time and are particularly well suited for tertiary amine substrates. A mechanistically distinct strategy for secondary amines has emerged only recently, despite sharing common features with a range of classic organic transformations. Among those are such widely used reactions as the Strecker, Mannich, Pictet-Spengler, and Kabachnik-Fields reactions, Friedel-Crafts alkylations, and iminium alkynylations. In these classic processes, condensation of a secondary amine with an aldehyde (or a ketone) typically leads to the formation of an intermediate iminium ion, which is subsequently attacked by a nucleophile. The corresponding redox-versions of these transformations utilize identical starting materials but incorporate an isomerization step that enables α-C-H bond functionalization. Intramolecular versions of these reactions include redox-neutral amine α-amination, α-oxygenation, and α-sulfenylation. In all cases, a reductive N-alkylation is effectively combined with an oxidative α-functionalization, generating water as the only byproduct. Reactions are promoted by simple carboxylic acids and in some cases require no additives. Azomethine ylides, dipolar species whose usage is predominantly in [3 + 2] cycloadditions and other pericyclic processes, have been

  16. Nano-organocatalyst: magnetically retrievable ferrite-anchored glutathione for microwave-assisted Paal–Knorr reaction, aza-Michael addition, and pyrazole synthesis

    KAUST Repository

    Polshettiwar, Vivek; Varma, Rajender S.

    2010-01-01

    Postsynthetic Surface modification of magnetic nanoparticles by glutathione imparts desirable chemical functionality and enables the generation of catalytic sites on the surfaces of ensuing organocatalysts. In this article, we discuss the developments, unique activity, and high selectivity of nano-organocatalysts for microwave-assisted Paal-Knorr reaction, aza-Michael addition, and pyrazole synthesis. Their insoluble character Coupled with paramagnetic nature enables easy separation of these nano-catalysts from the reaction mixture using external magnet, which eliminates the requirement of catalyst filtration. Published by Elsevier Ltd.

  17. Asymmetric NHC-catalyzed aza-Diels-Alder reactions: Highly enantioselective route to α-amino acid derivatives and DFT calculations

    KAUST Repository

    Yang, Limin

    2014-08-01

    A facile N-heterocyclic carbene catalytic enantioselective aza-Diels-Alder reaction of oxodiazenes with α-chloroaldehydes as dienophile precursors is reported, with excellent enantioselectivity (ee > 99%) and excellent yield (up to 93%). DFT study showed that cis-TSa, formed from a top face approach of oxodiazene to cis-IIa, is the most favorable transition state and is consistent with the experimental observations. © 2014 American Chemical Society.

  18. An efficient route for catalytic activity promotion via hybrid electro-depositional modification on commercial nickel foam for hydrogen evolution reaction in alkaline water electrolysis

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Guanshui; He, Yongwei; Wang, Mei; Zhu, Fuchun; Tang, Bin [Research Institute of Surface Engineering, Taiyuan University of Technology, Yingze West Road 79, Taiyuan 030024 (China); Wang, Xiaoguang, E-mail: wangxiaog1982@163.com [Research Institute of Surface Engineering, Taiyuan University of Technology, Yingze West Road 79, Taiyuan 030024 (China); International Iberian Nanotechnology Laboratory (INL), 4715-330 Braga (Portugal)

    2014-09-15

    Highlights: • Mono-Cu surface modification depress the HER activity of Ni-foam. • Hybrid Ni-foam/Cu0.01/Co0.05 exhibits superior HER performance. • Layer-by-layer structure may contribute to a synergistic promoting effect. - Abstract: In this paper, the single- and hybrid-layered Cu, Ni and Co thin films were electrochemically deposited onto the three-dimensional nickel foam as composite cathode catalyst for hydrogen evolution reaction in alkaline water electrolysis. The morphology, structure and chemical composition of the electrodeposited composite catalysts were investigated using X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDX). Electrochemical measurement depicted that, for the case of the monometallic layered samples, the general activity for hydrogen evolution reaction followed the sequence: Ni-foam/Ni > Ni-foam/Co > bare Ni-foam > Ni-foam/Cu. It is noteworthy that, the hybrid-layered Ni-foam/Cu0.01/Co0.05 exhibited the highest catalytic activity towards hydrogen evolution reaction with the current density as high as 2.82 times that of the bare Ni-foam. Moreover, both excellent electrochemical and physical stabilities can also be acquired on the Ni-foam/Cu0.01/Co0.05, making this hybrid-layered composite structure as a promising HER electro-catalyst.

  19. Pulsed laser-assisted focused electron-beam-induced etching of titanium with XeF2: enhanced reaction rate and precursor transport.

    Science.gov (United States)

    Noh, J H; Fowlkes, J D; Timilsina, R; Stanford, M G; Lewis, B B; Rack, P D

    2015-02-25

    In order to enhance the etch rate of electron-beam-induced etching, we introduce a laser-assisted focused electron-beam-induced etching (LA-FEBIE) process which is a versatile, direct write nanofabrication method that allows nanoscale patterning and editing. The results demonstrate that the titanium electron stimulated etch rate via the XeF2 precursor can be enhanced up to a factor of 6 times with an intermittent pulsed laser assist. The evolution of the etching process is correlated to in situ stage current measurements and scanning electron micrographs as a function of time. The increased etch rate is attributed to photothermally enhanced Ti-F reaction and TiF4 desorption and in some regimes enhanced XeF2 surface diffusion to the reaction zone.

  20. Nitropyrroles, Diels-Alder reactions assisted by microwave irradiation and solvent effect. An experimental and theoretical study

    Science.gov (United States)

    Mancini, Pedro M. E.; Kneeteman, María N.; Cainelli, Mauro; Ormachea, Carla M.; Domingo, Luis R.

    2017-11-01

    The behaviors of N-tosylnitropyrroles acting as electrophilic dienophiles in polar Diels-Alder reactions joint to different dienes of increeased nucleophilicity are analyzed. The reactions were developed under microwave irradiation using toluene or protic ionic liquids (PILs) as solvents and in free solvent conditions. In all the cases explored we observed good yields in short reaction times. For these reactions, the free solvent condition and the use of protic ionic liquids as solvents offer similar results. However, the free solvent conditions favor environmental sustainability. The role of PILs in these polar Diels-Alder reactions has been theoretically studied within the Molecular Electron Density Theory.

  1. Reactions to a Partner-Assisted Emotional Disclosure Intervention: Direct Observation and Self-Report of Patient and Partner Communication

    Science.gov (United States)

    Porter, Laura S.; Baucom, Donald H.; Keefe, Francis J.; Patterson, Emily S.

    2012-01-01

    Partner-assisted emotional disclosure is a couple-based intervention designed to help patients disclose cancer-related concerns to their spouses-partners. We previously found that, compared with an education/support control condition, partner-assisted emotional disclosure led to significant improvements in relationship quality and intimacy for…

  2. Characterization of nanostructured photosensitive (NiS)x(CdS)(1-x) composite thin films grown by successive ionic layer adsorption and reaction (SILAR) route

    International Nuclear Information System (INIS)

    Ubale, A.U.; Bargal, A.N.

    2011-01-01

    Highlights: → Thin films of (NiS) x (CdS) (1-x) with variable composition (x = 1 to 0) were deposited onto glass substrates by the successive ionic layer adsorption and reaction (SILAR) method. → The structural, surface morphological and electrical characterizations of the as deposited and annealed films were studied. → The bandgap and activation energy of annealed (NiS) x (CdS) (1-x) film decrease with improvement in photosensitive nature. -- Abstract: Recently ternary semiconductor nanostructured composite materials have attracted the interest of researchers because of their photovoltaic applications. Thin films of (NiS) x (CdS) (1-x) with variable composition (x = 1-0) had been deposited onto glass substrates by the successive ionic layer adsorption and reaction (SILAR) method. As grown and annealed films were characterised by X-ray diffraction, scanning electron microscopy and EDAX to investigate structural and morphological properties. The (NiS) x (CdS) (1-x) films were polycrystalline in nature having mixed phase of rhombohedral and hexagonal crystal structure due to NiS and CdS respectively. The optical and electrical properties of (NiS) x (CdS) (1-x) thin films were studied to determine compsition dependent bandgap, activation energy and photconductivity. The bandgap and activation energy of annealed (NiS) x (CdS) (1-x) film decrease with improvement in photosensitive nature.

  3. Characterization of nanostructured photosensitive (NiS){sub x}(CdS){sub (1-x)} composite thin films grown by successive ionic layer adsorption and reaction (SILAR) route

    Energy Technology Data Exchange (ETDEWEB)

    Ubale, A.U., E-mail: ashokuu@yahoo.com [Nanostructured Thin Film Materials Laboratory, Department of Physics, Govt. Vidarbha Institute of Science and Humanities, Amravati 444604, Maharashtra (India); Bargal, A.N. [Nanostructured Thin Film Materials Laboratory, Department of Physics, Govt. Vidarbha Institute of Science and Humanities, Amravati 444604, Maharashtra (India)

    2011-07-15

    Highlights: {yields} Thin films of (NiS){sub x}(CdS){sub (1-x)} with variable composition (x = 1 to 0) were deposited onto glass substrates by the successive ionic layer adsorption and reaction (SILAR) method. {yields} The structural, surface morphological and electrical characterizations of the as deposited and annealed films were studied. {yields} The bandgap and activation energy of annealed (NiS){sub x}(CdS){sub (1-x)} film decrease with improvement in photosensitive nature. -- Abstract: Recently ternary semiconductor nanostructured composite materials have attracted the interest of researchers because of their photovoltaic applications. Thin films of (NiS){sub x}(CdS){sub (1-x)} with variable composition (x = 1-0) had been deposited onto glass substrates by the successive ionic layer adsorption and reaction (SILAR) method. As grown and annealed films were characterised by X-ray diffraction, scanning electron microscopy and EDAX to investigate structural and morphological properties. The (NiS){sub x}(CdS){sub (1-x)} films were polycrystalline in nature having mixed phase of rhombohedral and hexagonal crystal structure due to NiS and CdS respectively. The optical and electrical properties of (NiS){sub x}(CdS){sub (1-x)} thin films were studied to determine compsition dependent bandgap, activation energy and photconductivity. The bandgap and activation energy of annealed (NiS){sub x}(CdS){sub (1-x)} film decrease with improvement in photosensitive nature.

  4. Materials and Mechanisms of Photo-Assisted Chemical Reactions under Light and Dark Conditions: Can Day-Night Photocatalysis Be Achieved?

    Science.gov (United States)

    Sakar, M; Nguyen, Chinh-Chien; Vu, Manh-Hiep; Do, Trong-On

    2018-03-09

    The photoassisted catalytic reaction, conventionally known as photocatalysis, is expanding into the field of energy and environmental applications. It is widely known that the discovery of TiO 2 -assisted photochemical reactions has led to several unique applications, such as degradation of pollutants in water and air, hydrogen production through water splitting, fuel conversion, cancer treatment, antibacterial activity, self-cleaning glasses, and concrete. These multifaceted applications of this phenomenon can be enriched and expanded further if this process is equipped with more tools and functions. The term "photoassisted" catalytic reactions clearly emphasizes that photons are required to activate the catalyst; this can be transcended even into the dark if electrons are stored in the material for the later use to continue the catalytic reactions in the absence of light. This can be achieved by equipping the photocatalyst with an electron-storage material to overcome current limitations in photoassisted catalytic reactions. In this context, this article sheds lights on the materials and mechanisms of photocatalytic reactions under light and dark conditions. The manifestation of such systems could be an unparalleled technology in the near future that could influence all spheres of the catalytic sciences. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. 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.

  6. 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

  7. 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

  8. 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...

  9. Investigation of activation cross section data of alpha particle induced nuclear reaction on molybdenum up to 40 MeV: Review of production routes of medically relevant {sup 97,103}Ru

    Energy Technology Data Exchange (ETDEWEB)

    Tárkányi, F. [Institute of Nuclear Research of the Hungarian Academy of Sciences, Debrecen (Hungary); Hermanne, A., E-mail: aherman@vub.ac.be [Cyclotron Laboratory, Vrije Universiteit Brussel, Brussels (Belgium); Ditrói, F.; Takács, S. [Institute of Nuclear Research of the Hungarian Academy of Sciences, Debrecen (Hungary); Ignatyuk, A. [Institute of Physics and Power Engineering (IPPE), Obninsk (Russian Federation)

    2017-05-15

    The main goals of this investigations were to expand and consolidate reliable activation cross-section data for the {sup nat}Mo(α,x) reactions in connection with production of medically relevant {sup 97,103}Ru and the use of the {sup nat}Mo(α,x){sup 97}Ru reaction for monitoring beam parameters. The excitation functions for formation of the gamma-emitting radionuclides {sup 94}Ru, {sup 95}Ru, {sup 97}Ru, {sup 103}Ru, {sup 93m}Tc, {sup 93g}Tc(m+), {sup 94m}Tc, {sup 94g}Tc, {sup 95m}Tc, {sup 95g}Tc, {sup 96g}Tc(m+), {sup 99m}Tc, {sup 93m}Mo, {sup 99}Mo(cum), {sup 90}Nb(m+) and {sup 88}Zr were measured up to 40 MeV alpha-particle energy by using the stacked foil technique and activation method. Data of our earlier similar experiments were re-evaluated and resulted in corrections on the reported results. Our experimental data were compared with critically analyzed literature data and with the results of model calculations, obtained by using the ALICE-IPPE, EMPIRE 3.1 (Rivoli) and TALYS codes (TENDL-2011 and TENDL-2015 on-line libraries). Nuclear data for different production routes of {sup 97}Ru and {sup 103}Ru are compiled and reviewed.

  10. Thermal replacement reaction: a novel route for synthesizing eco-friendly ZnO@γ-In2Se3 hetero-nanostructures by replacing cadmium with indium and their photoelectrochemical and photocatalytic performances.

    Science.gov (United States)

    Zhang, Zhuo; Choi, Mingi; Baek, Minki; Yong, Kijung

    2015-05-21

    A novel route called thermal replacement reaction was demonstrated for synthesizing eco-friendly ZnO@γ-In2Se3 hetero-structural nanowires on FTO glass by replacing the element cadmium with indium for the first time. The indium layer was coated on the surface of the ZnO nanowires beforehand, then CdSe quantum dots were deposited onto the coated indium layer, and finally the CdSe quantum dots were converted to γ-In2Se3 quantum dots by annealing under vacuum at 350 °C for one hour. The prepared ZnO@γ-In2Se3 hetero-nanostructures exhibit stable photoelectrochemical properties that can be ascribed to the protection of the In2O3 layer between the ZnO nanowire and γ-In2Se3 quantum dots and better photocatalytic performance in the wide wavelength region from 400 nm to nearly 750 nm. This strategy for preparing the ZnO@γ-In2Se3 hetero-nanostructures not only enriches our understanding of the single replacement reaction where the active element cadmium can be replaced with indium, but also opens a new way for the in situ conversion of cadmium-based to eco-friendly indium-based nano-devices.

  11. Nanostructural and magnetic studies of virtually monodispersed NiFe2O4 nanocrystals synthesized by a liquid–solid-solution assisted hydrothermal route

    International Nuclear Information System (INIS)

    Li Xinghua; Tan Guoguo; Chen Wei; Zhou Baofan; Xue Desheng; Peng Yong; Li, Fashen; Mellors, Nigel J.

    2012-01-01

    This study presents a comprehensively and systematically structural, chemical and magnetic characterization of ∼9.5 nm virtually monodispersed nickel ferrite (NiFe 2 O 4 ) nanoparticles prepared using a modified liquid–solid-solution (LSS) assisted hydrothermal method. Lattice-resolution scanning transmission electron microscope (STEM) and converged beam electron diffraction pattern (CBED) techniques are adapted to characterize the detailed spatial morphology and crystal structure of individual NiFe 2 O 4 particles at nano scale for the first time. It is found that each NiFe 2 O 4 nanoparticle is single crystal with an fcc structure. The morphology investigation reveals that the prepared NiFe 2 O 4 nanoparticles of which the surfaces are decorated by oleic acid are dispersed individually in hexane. The chemical composition of nickel ferrite nanoparticles is measured to be 1:2 atomic ratio of Ni:Fe, indicating a pure NiFe 2 O 4 composition. Magnetic measurements reveal that the as-synthesized nanocrystals displayed superparamagnetic behavior at room temperature and were ferromagnetic at 10 K. The nanoscale characterization and magnetic investigation of monodispersed NiFe 2 O 4 nanoparticles should be significant for its potential applications in the field of biomedicine and magnetic fluid using them as magnetic materials.

  12. A Microwave-Assisted Diastereoselective Multicomponent Reaction To Access Dibenzo[c,e]azepinones: Synthesis and Biological Evaluation

    NARCIS (Netherlands)

    Mehta, V.P.; Modha, S.G.; Ruijter, E.; van Hecke, K.; van Meervelt, L.; Pannecouque, C.; Balzarini, J.; Orru, R.V.A.; van der Eycken, E.

    2011-01-01

    An unprecedented microwave-assisted multicomponent strategy has been elaborated for the fast, efficient, and diastereoselective generation of the dibenzo[c,e]azepinone scaffold. The generated compounds were evaluated for their bioactivity. © 2011 American Chemical Society.

  13. Reactions of Fischer carbene complexes with Electron-deficient olefins: Scope and limitations of this route to donor-acceptor-substituted cyclopropanes

    Energy Technology Data Exchange (ETDEWEB)

    Wienand, A.; Reissig, H.U. (Inst. fuer Organische Chemie der Technischen Hochschule Darmstadt (West Germany))

    1990-12-01

    The Fischer carbene complex ((CO){sub 5}Cr{double bond}C(OMe)Ph) (1) is able to transfer its carbene ligand to a variety of electron-deficient olefins and provides donor-acceptor-substituted cyclopropanes in good yields. Apt activating groups with respect to the alkene are ester, amide, nitrile, sulfone, and dialkyl phosphonate functions. Methyl vinyl ketone (19) affords products in low yield that may arise from an intermediate cyclopropane derivative. Phenyl vinyl sulfoxide (24) mainly acts as an oxidizing agent, transforming 1 into methyl benzoate. for olefin 24 and {alpha}-(N-methylanilino)acrylonitrile the authors found products that should be formed on an olefin metathesis pathway. The methyl-substituted carbene complex 48 also affords the expected donor-acceptor-substituted cyclopropanes; however, acyclic isomers are formed in higher amounts. The molybdenum and tungsten complexes 55 and 56, respectively, also furnish cyclopropane derivatives, but the yields are lower than with the chromium compound 1. Disubstituted olefins and complex 1 still give the cyclopropanes in moderate yields, while all trisubstituted and most of the difunctionalized alkenes do not react with this Fischer carbene complex. The cyclopropanes synthesized can be deprotonated and alkylated or transformed into ring-opened products. These model reactions demonstrate the synthetic potentials of donor-acceptor-substituted cyclopropanes prepared via Fischer carbene complexes.

  14. Monoclinic β-Li{sub 2}TiO{sub 3} nanocrystalline particles employing novel urea assisted solid state route: Synthesis, characterization and sintering behavior

    Energy Technology Data Exchange (ETDEWEB)

    Tripathi, Biranchi M., E-mail: biranchi.barc@gmail.com [Powder Metallurgy Division, Bhabha Atomic Research Centre, Vashi Complex, Navi Mumbai 400705 (India); Mohanty, Trupti; Prakash, Deep [Powder Metallurgy Division, Bhabha Atomic Research Centre, Vashi Complex, Navi Mumbai 400705 (India); Tyagi, A.K. [Chemistry Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India); Sinha, P.K. [Powder Metallurgy Division, Bhabha Atomic Research Centre, Vashi Complex, Navi Mumbai 400705 (India)

    2017-07-15

    Pure phase monoclinic nano-crystalline Li{sub 2}TiO{sub 3} powder was synthesized by a novel urea assisted solid state synthesis method using readily available and economical precursors. A single phase and well crystalline Li{sub 2}TiO{sub 3} powder has been obtained at slightly lower temperature (600–700 °C) and shorter duration (2 h) as compared to the conventional solid state method. The proposed method has significant advantages in comparison to other viable methods mainly in terms of phase purity, powder properties and sinterability. Analysis of chemical composition using inductively coupled plasma atomic emission spectroscopy (ICP-AES) shows no loss of lithium from Li{sub 2}TiO{sub 3} in the proposed method. The emergence of monoclinic Li{sub 2}TiO{sub 3} phase was confirmed by X-ray diffraction (XRD) pattern of as-synthesized powder. The crystallite size of Li{sub 2}TiO{sub 3} powder was calculated to be in the range of 15–80 nm, which varied as a function of urea composition and temperature. The morphology of as-prepared Li{sub 2}TiO{sub 3} powders was examined by scanning electron microscope (SEM). The effect of urea composition on phase and morphology was investigated so as to delineate the role of urea. Upon sintering at < 1000 °C temperature, the Li{sub 2}TiO{sub 3} powder compact attained about 98% of the theoretical density with fine grained (grain size: 2–3 μm) microstructure. It indicates excellent sinter-ability of Li{sub 2}TiO{sub 3} powder synthesized by the proposed method. The fine grained structure is desirable for better tritium breeding performance of Li{sub 2}TiO{sub 3}. Electrochemical impedance spectroscopy at variable temperature showed good electrical properties of Li{sub 2}TiO{sub 3}. The proposed method is simple, anticipated to be cost effective and convenient to realise for large scale production of phase pure nanocrystalline and having significantly enhanced sinter-ability Li{sub 2}TiO{sub 3} powder.

  15. Ultrasound-assisted green synthesis of pyrroles and pyridazines in water via three-component condensation reactions of arylglyoxals

    Directory of Open Access Journals (Sweden)

    Bagher Eftekhari-Sis

    2013-04-01

    Full Text Available A green and efficient method for the preparation of 5-aryl-4-hydroxy-2-methyl-1H-pyrrole-3-carboxylic acid esters and 6-aryl-3-methylpyridazine-4-carboxylic acid esters via three-component reaction of arylglyoxal hydrates with β-dicarbonyl compounds in the presence of ammonium acetate and hydrazine hydrate using water as solvent under ultrasonic irradiation was reported. The reactions proceeded rapidly and afforded the corresponding pyrroles and pyridazines in good to high yields in very short reaction time.

  16. Tuning crystal phase of NiS_x through electro-oxidized nickel foam: A novel route for preparing efficient electrocatalysts for oxygen evolution reaction

    International Nuclear Information System (INIS)

    Li, Xiao; Shang, Xiao; Rao, Yi; Dong, Bin; Han, Guan-Qun; Hu, Wen-Hui; Liu, Yan-Ru; Yan, Kai-Li; Chi, Jing-Qi; Chai, Yong-Ming; Liu, Chen-Guang

    2017-01-01

    Highlights: • Electro-oxidized nickel foam as a support has been used to prepare NiS_x phases. • Ni(OH)_2 layer on electro-oxidized NF is responsible for the growth of β-NiS. • NiS_x/NF(Ox) composed of β-NiS and Ni_3S_2 has enhanced electrocatalytic activity. • The growth mechanisms of mixed NiS_x phases of NiS_x/NF(Ox) have been discussed. - Abstract: A facile solvothermal sulfurization using electro-oxidized nickel foam (NF(Ox)) as support has been applied to prepare NiS_x/NF(Ox) electrocatalyst with highly efficient activity for oxygen evolution reaction (OER). XRD patterns confirm the composition of NiS_x/NF(Ox): two kinds of crystal phase including β-NiS and Ni_3S_2. While using bare NF as support under identical conditions, only Ni_3S_2 phase can be detected. SEM images reveal two kinds of morphologies of NiS_x/NF(Ox) including pyramids structure of β-NiS and nanorod-like structure of Ni_3S_2, which implies the tuning effect of electro-pretreatment of NF on the selective preparation of NiS_x crystal phase. It can be speculated that Ni(OH)_2 layer derived from electro-oxidized NF is responsible for the growth of β-NiS while metallic Ni is transformed into Ni_2S_3 during sulfurization. Electrochemical measurements for OER indicate the enhanced electrocatalytic activity of NiS_x/NF(Ox) with a small overpotential of 72 mV to reach 10 mA cm"−"2 compared with Ni_3S_2/NF, which may be ascribed to the improved electron-transfer kinetics relating to the unique atomic configurations and crystalline structures of β-NiS. The electro-oxidation pretreatment of nickel foam provides a simple and convenient method by tuning different NiS_x crystal phases for preparing excellent OER eletrocatalysts.

  17. Tuning crystal phase of NiS{sub x} through electro-oxidized nickel foam: A novel route for preparing efficient electrocatalysts for oxygen evolution reaction

    Energy Technology Data Exchange (ETDEWEB)

    Li, Xiao; Shang, Xiao [State Key Laboratory of Heavy Oil Processing, China University of Petroleum (East China), Qingdao 266580 (China); Rao, Yi [State Key Laboratory of Heavy Oil Processing, China University of Petroleum (East China), Qingdao 266580 (China); College of Science, China University of Petroleum (East China), Qingdao 266580, PR China (China); Dong, Bin, E-mail: dongbin@upc.edu.cn [State Key Laboratory of Heavy Oil Processing, China University of Petroleum (East China), Qingdao 266580 (China); College of Science, China University of Petroleum (East China), Qingdao 266580, PR China (China); Han, Guan-Qun [State Key Laboratory of Heavy Oil Processing, China University of Petroleum (East China), Qingdao 266580 (China); College of Science, China University of Petroleum (East China), Qingdao 266580, PR China (China); Hu, Wen-Hui; Liu, Yan-Ru; Yan, Kai-Li; Chi, Jing-Qi; Chai, Yong-Ming [State Key Laboratory of Heavy Oil Processing, China University of Petroleum (East China), Qingdao 266580 (China); Liu, Chen-Guang, E-mail: cgliu@upc.edu.cn [State Key Laboratory of Heavy Oil Processing, China University of Petroleum (East China), Qingdao 266580 (China)

    2017-02-28

    Highlights: • Electro-oxidized nickel foam as a support has been used to prepare NiS{sub x} phases. • Ni(OH){sub 2} layer on electro-oxidized NF is responsible for the growth of β-NiS. • NiS{sub x}/NF(Ox) composed of β-NiS and Ni{sub 3}S{sub 2} has enhanced electrocatalytic activity. • The growth mechanisms of mixed NiS{sub x} phases of NiS{sub x}/NF(Ox) have been discussed. - Abstract: A facile solvothermal sulfurization using electro-oxidized nickel foam (NF(Ox)) as support has been applied to prepare NiS{sub x}/NF(Ox) electrocatalyst with highly efficient activity for oxygen evolution reaction (OER). XRD patterns confirm the composition of NiS{sub x}/NF(Ox): two kinds of crystal phase including β-NiS and Ni{sub 3}S{sub 2}. While using bare NF as support under identical conditions, only Ni{sub 3}S{sub 2} phase can be detected. SEM images reveal two kinds of morphologies of NiS{sub x}/NF(Ox) including pyramids structure of β-NiS and nanorod-like structure of Ni{sub 3}S{sub 2}, which implies the tuning effect of electro-pretreatment of NF on the selective preparation of NiS{sub x} crystal phase. It can be speculated that Ni(OH){sub 2} layer derived from electro-oxidized NF is responsible for the growth of β-NiS while metallic Ni is transformed into Ni{sub 2}S{sub 3} during sulfurization. Electrochemical measurements for OER indicate the enhanced electrocatalytic activity of NiS{sub x}/NF(Ox) with a small overpotential of 72 mV to reach 10 mA cm{sup −2} compared with Ni{sub 3}S{sub 2}/NF, which may be ascribed to the improved electron-transfer kinetics relating to the unique atomic configurations and crystalline structures of β-NiS. The electro-oxidation pretreatment of nickel foam provides a simple and convenient method by tuning different NiS{sub x} crystal phases for preparing excellent OER eletrocatalysts.

  18. Synthesis and magnetic characterization of Zn{sub 0.7}Ni{sub 0.3}Fe{sub 2}O{sub 4} nanoparticles via microwave-assisted combustion route

    Energy Technology Data Exchange (ETDEWEB)

    Sertkol, M. [Department of Physics, Fatih University, 34500 Buyukcekmece, Istanbul (Turkey); Koeseoglu, Y., E-mail: yukselk@fatih.edu.t [Department of Physics, Fatih University, 34500 Buyukcekmece, Istanbul (Turkey); Baykal, A. [Department of Chemistry, Fatih University, 34500 Buyukcekmece, Istanbul (Turkey); Kavas, H. [Department of Physics, Fatih University, 34500 Buyukcekmece, Istanbul (Turkey); Toprak, M.S. [Division of Functional Materials, Royal Institute of Technology (KTH), SE-16440 Stockholm (Sweden)

    2010-04-15

    We report on the synthesis of Zn{sub 0.7}Ni{sub 0.3}Fe{sub 2}O{sub 4} nanoparticles via microwave assisted combustion route by using urea as fuel. XRD and FT-IR analyses confirm the composition and structure as spinel ferrite. The crystallite size estimated from XRD (16.4 nm) and the magnetic core size (15.04 nm) estimated from VSM agree well, while a slightly smaller magnetic diameter reflects a very thin magnetically dead layer on the surface of the nanoparticles. Morphological investigation of the products was done by TEM which revealed the existence of irregular shapes such spherical, spherodial and polygon. Magnetization measurements performed on Zn{sub 0.7}Ni{sub 0.3}Fe{sub 2}O{sub 4} nanoparticles showed that saturation was not attained at even in the high magnetic field. The sample shows superparamagnetic behavior at around the room temperature and ferromagnetic behavior below the blocking temperature which is measured as 284 K.

  19. The optimized microwave-assisted decomposition of formamides and its synthetic utility in the amination reactions of purines

    Czech Academy of Sciences Publication Activity Database

    Čechová, Lucie; Jansa, Petr; Šála, Michal; Dračínský, Martin; Holý, Antonín; Janeba, Zlatko

    2011-01-01

    Roč. 67, č. 5 (2011), s. 866-871 ISSN 0040-4020 R&D Projects: GA MŠk 1M0508; GA AV ČR KJB400550903 Institutional research plan: CEZ:AV0Z40550506 Keywords : microwave-assisted synthesis * DMF * formamides * dehalogenative amination * purines Subject RIV: CC - Organic Chemistry Impact factor: 3.025, year: 2011

  20. Microwave-assisted clean synthesis of amides via aza-wittig reaction under solvent-free condition

    Energy Technology Data Exchange (ETDEWEB)

    Sathishkumar, Murugan; Nagarajan, Sangaraiah; Velan, Poovan Shanmuga; Dinesh, Murugan; Ponnuswamy, Alagusundaram [Department of Organic Chemistry, School of Chemistry, Madurai Kamaraj University, Tamilnadu (India)

    2011-09-15

    A solvent-free microwave-assisted coupling of phosphazenes with acyl chlorides or carboxylic anhydrides in presence of triethylphosphite has been accomplished resulting in a clean synthesis of amides in good yields. Unlike the prevailing time-consuming solution phase methodologies employing chlorinated solvents, benzene (carcinogenic), etc, the present protocol is an eco friendly, rapid and simple approach. (author)

  1. Plasma-assisted synthesis of monodispersed and robust Ruthenium ultrafine nanocatalysts for organosilane oxidation and oxygen evolution reactions

    NARCIS (Netherlands)

    Gnanakumar, E.S.; Ng, W.; Filiz, B.C.; Rothenberg, G.; Wang, S.; Xu, H.; Pastor-Pérez, L.; Pastor-Blas, M.M.; Sepúlveda-Escribano, A.; Yan, N.; Shiju, N.R.

    2017-01-01

    We report a facile and general approach for preparing ultrafine ruthenium nanocatalysts by using a plasma-assisted synthesis at <100 °C. The resulting Ru nanoparticles are monodispersed (typical size 2 nm) and remain that way upon loading onto carbon and TiO2 supports. This gives robust catalysts

  2. 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.

  3. Direct Energy Supply to the Reaction Mixture during Microwave-Assisted Hydrothermal and Combustion Synthesis of Inorganic Materials

    Directory of Open Access Journals (Sweden)

    Roberto Rosa

    2014-05-01

    Full Text Available The use of microwaves to perform inorganic synthesis allows the direct transfer of electromagnetic energy inside the reaction mixture, independently of the temperature manifested therein. The conversion of microwave (MW radiation into heat is useful in overcoming the activation energy barriers associated with chemical transformations, but the use of microwaves can be further extended to higher temperatures, thus creating unusual high-energy environments. In devising synthetic methodologies to engineered nanomaterials, hydrothermal synthesis and solution combustion synthesis can be used as reference systems to illustrate effects related to microwave irradiation. In the first case, energy is transferred to the entire reaction volume, causing a homogeneous temperature rise within a closed vessel in a few minutes, hence assuring uniform crystal growth at the nanometer scale. In the second case, strong exothermic combustion syntheses can benefit from the application of microwaves to convey energy to the reaction not only during the ignition step, but also while it is occurring and even after its completion. In both approaches, however, the direct interaction of microwaves with the reaction mixture can lead to practically gradient-less heating profiles, on the basis of which the main observed characteristics and properties of the aforementioned reactions and products can be explained.

  4. Computer-assisted study on the reaction between pyruvate and ylide in the pathway leading to lactyl-ThDP.

    Science.gov (United States)

    Alvarado, Omar; Jaña, Gonzalo; Delgado, Eduardo J

    2012-08-01

    In this study the formation of the lactyl-thiamin diphosphate intermediate (L-ThDP) is addressed using density functional theory calculations at X3LYP/6-31++G(d,p) level of theory. The study includes potential energy surface scans, transition state search, and intrinsic reaction coordinate calculations. Reactivity is analyzed in terms of Fukui functions. The results allow to conclude that the reaction leading to the formation of L-ThDP occurs via a concerted mechanism, and during the nucleophilic attack on the pyruvate molecule, the ylide is in its AP form. The calculated activation barrier for the reaction is 19.2 kcal/mol, in agreement with the experimental reported value.

  5. Microwave Assisted Synthesis of Osmium Electrocatalysts for the Oxygen Reduction Reaction in the Absence and Presence of Aqueous Methanol

    Directory of Open Access Journals (Sweden)

    Edgar Borja-Arco

    2011-01-01

    Full Text Available Osmium electrocatalysts for the oxygen reduction reaction (ORR were prepared by microwave irradiation of Os3(CO12 at different experimental conditions. The materials obtained were structurally characterized by FT-IR, micro-Raman spectroscopy and X-ray diffraction. Their chemical compositions were obtained by EDS. The electrocatalytic properties for the oxygen reduction reaction were evaluated by rotating disk electrode measurements in 0.5 mol L-1 H2SO4, in the absence and presence of aqueous methanol. The kinetic parameters, such as Tafel slope, exchange current density, and charge transfer coefficient are reported.

  6. 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.

  7. Nafion®-catalyzed microwave-assisted Ritter reaction: An atom-economic solvent-free synthesis of amides

    Science.gov (United States)

    An atom-economic solvent-free synthesis of amides by the Ritter reaction of alcohols and nitriles under microwave irradiation is reported. This green protocol is catalyzed by solid supported Nafion®NR50 with improved efficiency and reduced waste production.

  8. Ultrasensitive Faraday cage-type electrochemiluminescence assay for femtomolar miRNA-141 via graphene oxide and hybridization chain reaction-assisted cascade amplification.

    Science.gov (United States)

    Lu, Jing; Wu, Lin; Hu, Yufang; Wang, Sui; Guo, Zhiyong

    2018-06-30

    In this study, a novel electrochemiluminescence (ECL) biosensor for sensitive detection of femtomolar miRNA-141 was constructed on the basis of Faraday cage-type strategy via graphene oxide (GO) and hybridization chain reaction (HCR)-assisted cascade amplification. A capture probe (CP) was immobilized on Fe 3 O 4 @SiO 2 @Au nanoparticles as capture unit, which could catch the miRNA-141, and the immobilization of the signal unit (Ru(phen) 3 2+ -HCR/GO) was allowed via nucleic acid hybridization. The prepared biosensor exhibited two advantages for signal amplification: firstly, GO could lap on the electrode surface directly, extending Outer Helmholtz Plane (OHP) of the sensor due to the large surface area and good electronic transport property; secondly, HCR-assisted cascade amplification was designed by anchoring all HCR products on the GO surface, then embedding Ru(phen) 3 2+ as a signal readout pathway. All these signal molecules could take part in electrochemical reactions, thus further enhancing the ECL signal drastically. Therefore, the proposed sensor constructed by integrating HCR with Faraday cage-type strategy displayed an ultrasensitive detection platform for the miRNA-141 with a low detection limit of 0.03 fM. In addition, this proposed biosensor provides a universal platform for analysis of other microRNAs. Copyright © 2018 Elsevier B.V. All rights reserved.

  9. 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...

  10. Novel binder-free forming of Al2O3 ceramics by microwave-assisted hydration reaction

    International Nuclear Information System (INIS)

    Shirai, Takashi; Yasuoka, Masaki; Watari, Koji

    2008-01-01

    A novel binder-free forming of ceramics via microwave irradiation is developed. The irradiation of microwave to an alumina green body enhances the hydration reaction strongly between water and particle surfaces, creating surface aluminum trihydroxides structure adjacent to particles that bind them together tightly. This process makes it possible to manufacture mechanically strong green bodies with excellent shape retention ability without the use of organic binders

  11. 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...

  12. Kinetic and mechanistic studies of reactive intermediates in photochemical and transition metal-assisted oxidation, decarboxylation and alkyl transfer reactions

    Energy Technology Data Exchange (ETDEWEB)

    Carraher, Jack McCaslin [Iowa State Univ., Ames, IA (United States)

    2014-01-01

    Reactive species like high-valent metal-oxo complexes and carbon and oxygen centered radicals are important intermediates in enzymatic systems, atmospheric chemistry, and industrial processes. Understanding the pathways by which these intermediates form, their relative reactivity, and their fate after reactions is of the utmost importance. Herein are described the mechanistic detail for the generation of several reactive intermediates, synthesis of precursors, characterization of precursors, and methods to direct the chemistry to more desirable outcomes yielding ‘greener’ sources of commodity chemicals and fuels.

  13. Silver nanoclusters-assisted ion-exchange reaction with CdTe quantum dots for photoelectrochemical detection of adenosine by target-triggering multiple-cycle amplification strategy.

    Science.gov (United States)

    Zhao, Yang; Tan, Lu; Gao, Xiaoshan; Jie, Guifen; Huang, Tingyu

    2018-07-01

    Herein, we successfully devised a novel photoelectrochemical (PEC) platform for ultrasensitive detection of adenosine by target-triggering cascade multiple cycle amplification based on the silver nanoparticles-assisted ion-exchange reaction with CdTe quantum dots (QDs). In the presence of target adenosine, DNA s1 is released from the aptamer and then hybridizes with hairpin DNA (HP1), which could initiate the cycling cleavage process under the reaction of nicking endonuclease. Then the product (DNA b) of cycle I could act as the "DNA trigger" of cycle II to further generate a large number of DNA s1, which again go back to cycle I, thus a cascade multiple DNA cycle amplification was carried out to produce abundant DNA c. These DNA c fragments with the cytosine (C)-rich loop were captured by magnetic beads, and numerous silver nanoclusters (Ag NCs) were synthesized by AgNO 3 and sodium borohydride. The dissolved AgNCs released numerous silver ions which could induce ion exchange reaction with the CdTe QDs, thus resulting in greatly amplified change of photocurrent for target detection. The detection linear range for adenosine was 1.0 fM ~10 nM with the detection limit of 0.5 fM. The present PEC strategy combining cascade multiple DNA cycle amplification and AgNCs-induced ion-exchange reaction with QDs provides new insight into rapid, and ultrasensitive PEC detection of different biomolecules, which showed great potential for detecting trace amounts in bioanalysis and clinical biomedicine. Copyright © 2018 Elsevier B.V. All rights reserved.

  14. Mobility Tolerant Firework Routing for Improving Reachability in MANETs

    Directory of Open Access Journals (Sweden)

    Gen Motoyoshi

    2014-03-01

    Full Text Available In this paper, we investigate our mobility-assisted and adaptive broadcast routing mechanism, called Mobility Tolerant Firework Routing (MTFR, which utilizes the concept of potentials for routing and improves node reachability, especially in situations with high mobility, by including a broadcast mechanism. We perform detailed evaluations by simulations in a mobile environment and demonstrate the advantages of MTFR over conventional potential-based routing. In particular, we show that MTFR produces better reachability in many aspects at the expense of a small additional transmission delay and intermediate traffic overhead, making MTFR a promising routing protocol and feasible for future mobile Internet infrastructures.

  15. Chloroacetone photodissociation at 193 nm and the subsequent dynamics of the CH3C(O)CH2 radical—an intermediate formed in the OH + allene reaction en route to CH3 + ketene

    Science.gov (United States)

    Alligood, Bridget W.; FitzPatrick, Benjamin L.; Szpunar, David E.; Butler, Laurie J.

    2011-02-01

    We use a combination of crossed laser-molecular beam experiments and velocity map imaging experiments to investigate the primary photofission channels of chloroacetone at 193 nm; we also probe the dissociation dynamics of the nascent CH3C(O)CH2 radicals formed from C-Cl bond fission. In addition to the C-Cl bond fission primary photodissociation channel, the data evidence another photodissociation channel of the precursor, C-C bond fission to produce CH3CO and CH2Cl. The CH3C(O)CH2 radical formed from C-Cl bond fission is one of the intermediates in the OH + allene reaction en route to CH3 + ketene. The 193 nm photodissociation laser allows us to produce these CH3C(O)CH2 radicals with enough internal energy to span the dissociation barrier leading to the CH3 + ketene asymptote. Therefore, some of the vibrationally excited CH3C(O)CH2 radicals undergo subsequent dissociation to CH3 + ketene products; we are able to measure the velocities of these products using both the imaging and scattering apparatuses. The results rule out the presence of a significant contribution from a C-C bond photofission channel that produces CH3 and COCH2Cl fragments. The CH3C(O)CH2 radicals are formed with a considerable amount of energy partitioned into rotation; we use an impulsive model to explicitly characterize the internal energy distribution. The data are better fit by using the C-Cl bond fission transition state on the S1 surface of chloroacetone as the geometry at which the impulsive force acts, not the Franck-Condon geometry. Our data suggest that, even under atmospheric conditions, the reaction of OH with allene could produce a small branching to CH3 + ketene products, rather than solely producing inelastically stabilized adducts. This additional channel offers a different pathway for the OH-initiated oxidation of such unsaturated volatile organic compounds, those containing a C=C=C moiety, than is currently included in atmospheric models.

  16. 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

  17. Longitudinally Controlled Modification of Cylindrical and Conical Track-Etched Poly(ethylene terephthalate) Pores Using an Electrochemically Assisted Click Reaction

    International Nuclear Information System (INIS)

    Coceancigh, Herman; Tran-Ba, Khanh-Hoa; Columbia University, New York, NY; Siepser, Natasha; Baker, Lane A.; Ito, Takashi

    2017-01-01

    Here in this study, the longitudinally controlled modification of the inner surfaces of poly(ethylene terephthalate) (PET) track-etched pores was explored using an electrochemically assisted Cu(I)-catalyzed azide–alkyne cycloaddition (CuAAC) click reaction. Cylindrical or conical PET track-etched pores were first decorated with ethynyl groups via the amidation of surface -COOH groups, filled with a solution containing Cu(II) and azide-tagged fluorescent dye, and then sandwiched between comb-shaped and planar gold electrodes. Cu(I) was produced at the comb-shaped working electrode by the reduction of Cu(II); it diffused along the pores toward the other electrode and catalyzed CuAAC between an azide-tagged fluorescent dye and a pore-tethered ethynyl group. The modification efficiency of cylindrical pores (ca. 1 μm in diameter) was assessed from planar and cross-sectional fluorescence microscope images of modified membranes. Planar images showed that pore modification took place only above the teeth of the comb-shaped electrode with a higher reaction yield for longer Cu(II) reduction times. Cross-sectional images revealed micrometer-scale gradient modification along the pore axis, which reflected a Cu(I) concentration profile within the pores, as supported by finite-element computer simulations. The reported approach was applicable to the asymmetric modification of cylindrical pores with two different fluorescent dyes in the opposite directions and also for the selective visualization of the tip and base openings of conical pores (ca. 3.5 μm in base diameter and ca. 1 μm in tip diameter). Lastly, the method based on electrochemically assisted CuAAC provides a controlled means to fabricate asymmetrically modified nanoporous membranes and, in the future, will be applicable for chemical separations and the development of sequential catalytic reactors.

  18. Combustion characteristics and influential factors of isooctane active-thermal atmosphere combustion assisted by two-stage reaction of n-heptane

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Xingcai; Ji, Libin; Ma, Junjun; Zhou, Xiaoxin; Huang, Zhen [Key Lab. for Power Machinery and Engineering of MOE, Shanghai Jiao Tong University, 200240 Shanghai (China)

    2011-02-15

    This paper presents an experimental study on the isooctane active-thermal atmosphere combustion (ATAC) which is assisted by two-stage reaction of n-heptane. The active-thermal atmosphere is created by low- and high-temperature reactions of n-heptane which is injected at intake port, and isooctane is directly injected into combustion chamber near the top dead center. The effects of isooctane injection timing, active-thermal atmosphere intensity, overall equivalence ratio, and premixed ratio on combustion characteristics and emissions are investigated. The experimental results reveal that, the isooctane ignition and combustion can be classified to thermal atmosphere combustion, active atmosphere combustion, and active-thermal atmosphere combustion respectively according to the extent of n-heptane oxidation as well as effects of isooctane quenching and charge cooling. n-Heptane equivalence ratio, isooctane equivalence ratio and isooctane delivery advance angle are major control parameters. In one combustion cycle, the isooctane ignited and burned after those of n-heptane, and then this combustion phenomenon can also be named as dual-fuel sequential combustion (DFSC). The ignition timing of the overall combustion event is mainly determined by n-heptane equivalence ratio and can be controlled in flexibility by simultaneously adjusting isooctane equivalence ratio. The isooctane ignition regime, overall thermal efficiency, and NO{sub x} emissions show strong sensitivity to the fuel delivery advance angle between 20 CA BTDC and 25 CA BTDC. (author)

  19. Salt-assisted clean transfer of continuous monolayer MoS2 film for hydrogen evolution reaction

    Science.gov (United States)

    Cho, Heung-Yeol; Nguyen, Tri Khoa; Ullah, Farman; Yun, Jong-Won; Nguyen, Cao Khang; Kim, Yong Soo

    2018-03-01

    The transfer of two-dimensional (2D) materials from one substrate to another is challenging but of great importance for technological applications. Here, we propose a facile etching and residue-free method for transferring a large-area monolayer MoS2 film continuously grown on a SiO2/Si by chemical vapor deposition. Prior to synthesis, the substrate is dropped with water- soluble perylene-3, 4, 9, 10-tetracarboxylic acid tetrapotassium salt (PTAS). The as-grown MoS2 on the substrate is simply dipped in water to quickly dissolve PTAS to yield the MoS2 film floating on the water surface, which is subsequently transferred to the desired substrate. The morphological, optical and X-ray photoelectron spectroscopic results show that our method is useful for fast and clean transfer of the MoS2 film. Specially, we demonstrate that monolayer MoS2 film transferred onto a conducting substrate leads to excellent performance for hydrogen evolution reaction with low overpotential (0.29 V vs the reversible hydrogen electrode) and Tafel slope (85.5 mV/decade).

  20. Evaluation and Enhancement of the Oxygen Reduction Reaction Activity on Hafnium Oxide Nanoparticles Assisted by L(+)-lysine

    International Nuclear Information System (INIS)

    Chisaka, Mitsuharu; Itagaki, Noriaki

    2016-01-01

    Evaluation of the oxygen reduction reaction (ORR) on oxide compounds is difficult owing to the insulating nature of oxides. In this study, various amounts of L(+)-lysine were added to the precursor dispersion for the hydrothermal synthesis of hafnium oxide nanoparticles on reduced graphene oxide sheets (HfO_x–rGO) to coat the HfO_x catalysts with layers of carbon, thereby increasing the conductivity and number of active sites. When the mass ratio of L(+)-lysine to GO, R, was above 26, carbon layers were formed and the amount monotonically increased with increasing R, as noted by cyclic voltammogrametry. X-ray photoelectron spectroscopy and rotating disk electrode analyses revealed that pyrolysis produced ORR-active oxygen defects, whose formation was proposed to involve carbothermal reduction. When 53 ≤ R ≤ 210, HfO_x–rGO contained a similar amount of oxygen defects and ORR activity, as represented by an onset potential of 0.9 V versus the reversible hydrogen electrode in 0.1 mol dm"−"3 H_2SO_4. However, the number of active sites depended on R due to the amount of L(+)-lysine-derived carbon layers that increased both the number of active sites and resistivity towards oxygen diffusion.

  1. Pressure-assisted reaction bonding between W and Si80Ge20 alloy with Ni as the interlayer

    International Nuclear Information System (INIS)

    Xu, Y.; Laabs, F.C.; Beaudry, B.J.; Gschneidner, K.A. Jr.

    1991-01-01

    The conditions and reaction mechanism of W/Ni/Si 80 Ge 20 hot-press bonding have been studied. It was found that a Ni/Si 80 Ge 20 bond can be formed using low pressure, 19.6 MPa, in the temperature range between 780 and 900 degree C in a short time. The kinetics follows a parabolic pattern, suggesting it is a diffusion-controlled process. The activation energy is 2.7 eV and the parabolic rate constant is given by K P = 4.0 x 10 14 exp(-3.2x10 4 /T) (μm 2 /min). The bonding interface has a multilayered structure. A phenomenological mechanism of the bonding formation has been proposed based on scanning electron microscopy observations and energy dispersive spectroscopy. The cracking problem due to thermal stress is discussed based on Oxx's equation. It was found that bonds free from cracks in the Si 80 Ge 20 alloy are formed when the Ni consumption (as measured by the thickness of the nickel layer) is sufficiently small ( 4 . As an interlayer, nickel can join the tungsten sheet and the Si 80 Ge 20 together. It has been also demonstrated that a thin nickel layer formed by vapor deposition on a tungsten sheet may be used as the interlayer in place of nickel sheet

  2. Cationic polyelectrolyte functionalized magnetic particles assisted highly sensitive pathogens detection in combination with polymerase chain reaction and capillary electrophoresis.

    Science.gov (United States)

    Chen, Jia; Lin, Yuexin; Wang, Yu; Jia, Li

    2015-06-01

    Pathogenic bacteria cause significant morbidity and mortality to humans. There is a pressing need to establish a simple and reliable method to detect them. Herein, we show that magnetic particles (MPs) can be functionalized by poly(diallyl dimethylammonium chloride) (PDDA), and the particles (PDDA-MPs) can be utilized as adsorbents for capture of pathogenic bacteria from aqueous solution based on electrostatic interaction. The as-prepared PDDA-MPs were characterized by Fourier-transform infrared spectroscopy, zeta potential, vibrating sample magnetometry, X-ray diffraction spectrometry, scanning electron microscopy, and transmission electron microscopy. The adsorption equilibrium time can be achieved in 3min. According to the Langmuir adsorption isotherm, the maximum adsorption capacities for E. coli O157:H7 (Gram-negative bacteria) and L. monocytogenes (Gram-positive bacteria) were calculated to be 1.8×10(9) and 3.1×10(9)cfumg(-1), respectively. The bacteria in spiked mineral water (1000mL) can be completely captured when applying 50mg of PDDA-MPs and an adsorption time of 5min. In addition, PDDA-MPs-based magnetic separation method in combination with polymerase chain reaction and capillary electrophoresis allows for rapid detection of 10(1)cfumL(-1) bacteria. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. Kinetic and mechanistic studies of reactive intermediates in photochemical and transition metal-assisted oxidation, decarboxylation and alkyl transfer reactions

    Science.gov (United States)

    Carraher, Jack McCaslin

    Reactive species like high-valent metal-oxo complexes and carbon and oxygen centered radicals are important intermediates in enzymatic systems, atmospheric chemistry, and industrial processes. Understanding the pathways by which these intermediates form, their relative reactivity, and their fate after reactions is of the utmost importance. Herein are described the mechanistic detail for the generation of several reactive intermediates, synthesis of precursors, characterization of precursors, and methods to direct the chemistry to more desirable outcomes yielding 'greener' sources of commodity chemicals and fuels. High-valent Chromium from Hydroperoxido-Chromium(III). The decomposition of pentaaquahydroperoxido chromium(III) ion (hereafter Cr aqOOH2+) in acidic aqueous solutions is kinetically complex and generates mixtures of products (Craq3+, HCrO 4-, H2O2, and O2). The yield of high-valent chromium products (known carcinogens) increased from a few percent at pH 1 to 70 % at pH 5.5 (near biological pH). Yields of H 2O2 increased with acid concentration. The reproducibility of the kinetic data was poor, but became simplified in the presence of H2O2 or 2,2‧-azinobis(3-ethylbenzothiazoline-6-sulfonate) dianion (ABTS2-). Both are capable of scavenging strongly oxidizing intermediates). The observed rate constants (pH 1, [O2] ≤ 0.03 mM) in the presence of these scavengers are independent of [scavenger] and within the error are the same (k,ABTS2- = (4.9 +/- 0.2) x 10-4 s-1 and kH2O2 = (5.3 +/- 0.7) x 10-4 s-1); indicating involvement of the scavengers in post-rate determining steps. In the presence of either scavenger, decomposition of CrOOH2+ obeyed a two-term rate law, k obs / s-1 = (6.7 +/- 0.7) x 10-4 + (7.6 +/- 1.1) x 10-4 [H+]. Effect of [H+] on the kinetics and the product distribution, cleaner kinetics in the presence of scavengers, and independence of kobs on [scavenger] suggest a dual-pathway mechanism for the decay of Craq OOH2+. The H+-catalyzed path

  4. A prediction model-based algorithm for computer-assisted database screening of adverse drug reactions in the Netherlands.

    Science.gov (United States)

    Scholl, Joep H G; van Hunsel, Florence P A M; Hak, Eelko; van Puijenbroek, Eugène P

    2018-02-01

    The statistical screening of pharmacovigilance databases containing spontaneously reported adverse drug reactions (ADRs) is mainly based on disproportionality analysis. The aim of this study was to improve the efficiency of full database screening using a prediction model-based approach. A logistic regression-based prediction model containing 5 candidate predictors was developed and internally validated using the Summary of Product Characteristics as the gold standard for the outcome. All drug-ADR associations, with the exception of those related to vaccines, with a minimum of 3 reports formed the training data for the model. Performance was based on the area under the receiver operating characteristic curve (AUC). Results were compared with the current method of database screening based on the number of previously analyzed associations. A total of 25 026 unique drug-ADR associations formed the training data for the model. The final model contained all 5 candidate predictors (number of reports, disproportionality, reports from healthcare professionals, reports from marketing authorization holders, Naranjo score). The AUC for the full model was 0.740 (95% CI; 0.734-0.747). The internal validity was good based on the calibration curve and bootstrapping analysis (AUC after bootstrapping = 0.739). Compared with the old method, the AUC increased from 0.649 to 0.740, and the proportion of potential signals increased by approximately 50% (from 12.3% to 19.4%). A prediction model-based approach can be a useful tool to create priority-based listings for signal detection in databases consisting of spontaneous ADRs. © 2017 The Authors. Pharmacoepidemiology & Drug Safety Published by John Wiley & Sons Ltd.

  5. Biogenesis of Triterpene Dimers from Orthoquinones Related to Quinonemethides: Theoretical Study on the Reaction Mechanism

    Directory of Open Access Journals (Sweden)

    Mariana Quesadas-Rojas

    2016-11-01

    Full Text Available The biogenetic origin of triterpene dimers from the Celastraceae family has been proposed as assisted hetero-Diels-Alder reaction (HDA. In this work, computational calculation of HDA between natural quinonemethides (tingenone and isopristimerol and hypothetical orthoquinones has been performed at the M06-2X/6-31G(d level of theory. We have located all the HDA transition states supporting the biogenetic route via HDA cycloadditions. We found that all reactions take place through a concerted inverse electron demand and asynchronous mechanism. The enzymatic assistance for dimer formation was analyzed in terms of the calculated transition state energy barrier.

  6. Long Island north shore helicopter route environmental study

    Science.gov (United States)

    2012-02-21

    This report presents the results of the noise and emissions analysis of helicopter operations along the North Shore Helicopter Route of Long Island, New York performed by the Federal Aviation Administration, with the assistance of the Volpe Center...

  7. Indiana Underground Railroad Folklore: Western Route and Daviess County.

    Science.gov (United States)

    Shelton, Lois G.

    Materials for teaching a unit about the Underground Railroad (the system set up to assist fleeing, runaway slaves heading north) in Indiana are presented. Specifically, the Western Route that passed through Daviess County in Indiana is examined. The materials provide background on the Underground Railroad and the Western Route, plans for teaching…

  8. Combination of in situ metathesis reaction with a novel "magnetic effervescent tablet-assisted ionic liquid dispersive microextraction" for the determination of endogenous steroids in human fluids.

    Science.gov (United States)

    Wu, Jia; Xu, Zilin; Pan, Yixuan; Shi, Yi; Bao, Xiujie; Li, Jun; Tong, Yu; Tang, Han; Ma, Shuyan; Wang, Xuedong; Lyu, Jianxin

    2018-05-01

    Herein, a novel magnetic effervescence tablet-assisted microextraction coupled to in situ metathesis reaction of ionic liquid (IS-META-ILDM) is presented for the determination of four endogenous steroids in human urine, pregnant women's blood, and fetal umbilical cord blood. The magnetic effervescent tablets, which were composed of Fe 3 O 4 nanoparticles, sodium carbonate (alkaline source), and tartaric acid (acidic source), were used to disperse the extractant and for convenient magnetic separation. After the effervescent reaction, in situ reaction between NH 4 PF 6 and [C 6 MIM]BF 4 was adopted to change hydrophilic ionic liquid to hydrophobic liquid, which could be separated from the aqueous phase. The newly developed method has three obvious advantages: (1) combination of effervescent dispersion and magnetic nanoparticles' retrieval is cost-effective and the dispersion and collection of the extractant can be completed almost simultaneously; (2) as compared to temperature-controlled ionic liquid dispersive microextraction and cold-induced solidified microextraction, this method avoids a heating and cooling process which significantly reduces the extraction time and energy cost; and (3) the combination of adsorption by magnetic nanoparticles with extraction by in situ metathesis reaction easily produces high recoveries for target analytes. The optimized composition of effervescent tablet and experimental parameters are as follows: 0.64 g mixture of sodium carbonate and tartaric acid, 7 mg of Fe 3 O 4 (20 nm) as magnetic sorbents, 40 μL of [C 6 MIM]BF 4 as the extraction solvent, 0.15 g NH 4 PF 6 , and 300 μL of elution solvent. Under the optimized conditions, the newly developed method provided high extraction recoveries (90.0-118.5%) and low LODs (0.14-0.17 μg L -1 ) in urine and blood samples. In total, this IS-META-ILDM method provided high extraction efficiency, fast and convenient separation, and underutilization of any organic solvent, and thus

  9. Interdiffusion Reaction-Assisted Hybridization of Two-Dimensional Metal-Organic Frameworks and Ti3C2Tx Nanosheets for Electrocatalytic Oxygen Evolution.

    Science.gov (United States)

    Zhao, Li; Dong, Biliang; Li, Shaozhou; Zhou, Lijun; Lai, Linfei; Wang, Zhiwei; Zhao, Shulin; Han, Min; Gao, Kai; Lu, Min; Xie, Xiaoji; Chen, Bo; Liu, Zhengdong; Wang, Xiangjing; Zhang, Hao; Li, Hai; Liu, Juqing; Zhang, Hua; Huang, Xiao; Huang, Wei

    2017-06-27

    Two-dimensional (2D) metal-organic framework (MOF) nanosheets have been recently regarded as the model electrocatalysts due to their porous structure, fast mass and ion transfer through the thickness, and large portion of exposed active metal centers. Combining them with electrically conductive 2D nanosheets is anticipated to achieve further improved performance in electrocatalysis. In this work, we in situ hybridized 2D cobalt 1,4-benzenedicarboxylate (CoBDC) with Ti 3 C 2 T x (the MXene phase) nanosheets via an interdiffusion reaction-assisted process. The resulting hybrid material was applied in the oxygen evolution reaction and achieved a current density of 10 mA cm -2 at a potential of 1.64 V vs reversible hydrogen electrode and a Tafel slope of 48.2 mV dec -1 in 0.1 M KOH. These results outperform those obtained by the standard IrO 2 -based catalyst and are comparable with or even better than those achieved by the previously reported state-of-the-art transition-metal-based catalysts. While the CoBDC layer provided the highly porous structure and large active surface area, the electrically conductive and hydrophilic Ti 3 C 2 T x nanosheets enabled the rapid charge and ion transfer across the well-defined Ti 3 C 2 T x -CoBDC interface and facilitated the access of aqueous electrolyte to the catalytically active CoBDC surfaces. The hybrid nanosheets were further fabricated into an air cathode for a rechargeable zinc-air battery, which was successfully used to power a light-emitting diode. We believe that the in situ hybridization of MXenes and 2D MOFs with interface control will provide more opportunities for their use in energy-based applications.

  10. Ultrasensitive electrochemical detection of DNA based on Zn²⁺ assistant DNA recycling followed with hybridization chain reaction dual amplification.

    Science.gov (United States)

    Qian, Yong; Wang, Chunyan; Gao, Fenglei

    2015-01-15

    A new strategy to combine Zn(2+) assistant DNA recycling followed with hybridization chain reaction dual amplification was designed for highly sensitive electrochemical detection of target DNA. A gold electrode was used to immobilize molecular beacon (MB) as the recognition probe and perform the amplification procedure. In the presence of the target DNA, the hairpin probe 1 was opened, and the DNAzyme was liberated from the caged structure. The activated DNAzyme hybridized with the MB and catalyzed its cleavage in the presence of Zn(2+) cofactor and resulting in a free DNAzyme strand. Finally, each target-induced activated DNAzyme underwent many cycles triggering the cleavage of MB, thus forming numerous MB fragments. The MB fragments triggered the HCR and formed a long double-helix DNA structure. Because both H1 and H2 were labeled by biotin, a lot of SA-ALP was captured on the electrode surface, thus catalyzing a silver deposition process for electrochemical stripping analysis. This novel cascade signal amplification strategy can detect target DNA down to the attomolar level with a dynamic range spanning 6 orders of magnitude. This highly sensitive and specific assay has a great potential to become a promising DNA quantification method in biomedical research and clinical diagnosis. Copyright © 2014 Elsevier B.V. All rights reserved.

  11. 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)

  12. 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).

  13. 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...

  14. 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.

  15. 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...

  16. 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....

  17. 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.

  18. Multicomponent Reaction of Z-Chlorooximes, Isocyanides, and Hydroxylamines as Hypernucleophilic Traps. A One-Pot Route to Aminodioximes and Their Transformation into 5-Amino-1,2,4-oxadiazoles by Mitsunobu-Beckmann Rearrangement.

    Science.gov (United States)

    Mercalli, Valentina; Massarotti, Alberto; Varese, Monica; Giustiniano, Mariateresa; Meneghetti, Fiorella; Novellino, Ettore; Tron, Gian Cesare

    2015-10-02

    Synthetically useful aminodioximes are prepared via a novel three-component reaction among Z-chlorooximes, isocyanides, and hydroxylamines by exploiting the preferential attack of isocyanides to nitrile N-oxides via a [3 + 1] cycloaddition reaction. The results of quantum mechanical studies of the reaction mechanism are also discussed. Furthermore, the one-pot conversion of aminodioximes to 1,2,3-oxadiazole-5-amines via Mitsunobu-Beckmann rearrangement is reported for the first time.

  19. Synthesis and Computational Studies Demonstrate the Utility of an Intramolecular Styryl Diels-Alder Reaction and Di-t-butylhydroxytoluene Assisted [1,3]-Shift to Construct Anticancer dl-Deoxypodophyllotoxin.

    Science.gov (United States)

    Saavedra, Diana I; Rencher, Benjamin D; Kwon, Doo-Hyun; Smith, Stacey J; Ess, Daniel H; Andrus, Merritt B

    2018-02-16

    Deoxypodophyllotoxin is a secondary metabolite lignan possessing potent anticancer activity with potential as a precursor for known anticancer drugs, but its use is limited by scarcity from natural sources. We here report the total synthesis of racemic deoxypodophyllotoxin in seven steps using an intramolecular styryl Diels-Alder reaction strategy uniquely suited to assemble the deoxypodophyllotoxin core. Density functional theory was used to analyze concerted, polar, and singlet-open-shell diradical reaction pathways, which identified a low-energy concerted [4 + 2] Diels-Alder pathway followed by a faster di-t-butylhydroxytoluene assisted [1,3]-formal hydrogen shift.

  20. 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)

  1. 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.

  2. 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)

  3. 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

  4. Electrochemically assisted organosol method for Pt-Sn nanoparticle synthesis and in situ deposition on graphite felt support: Extended reaction zone anodes for direct ethanol fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Lycke, Derek R.; Gyenge, Elod L. [Department of Chemical and Biological Engineering, The University of British Columbia, 2360 East Mall, Vancouver, BC (Canada)

    2007-03-20

    Two electrochemically assisted variants of the Boenneman organosol method were developed for Pt-Sn nanoparticle synthesis and in situ deposition on graphite felt electrodes (e.g. thickness up to 2 mm). Tetraoctylammonium triethylhydroborate N(C{sub 8}H{sub 17}){sub 4}BH(C{sub 2}H{sub 5}){sub 3} was employed as colloid stabilizer and reductant dissolved in tetrahydrofuran (THF). The role of the electric field at a low deposition current density of 1.25 mA cm{sup -2} was mainly electrophoretic causing the migration and adsorption of N(C{sub 8}H{sub 17}){sub 4}BH(C{sub 2}H{sub 5}){sub 3} on the graphite felt surface where it reduced the PtCl{sub 2}-SnCl{sub 2} mixture. Faradaic electrodeposition was detected mostly for Sn. Typical Pt-Sn loadings were between 0.4 and 0.9 mg cm{sup -2} depending on the type of pre-deposition exposure of the graphite felt: surfactant-adsorption and metal-adsorption variant, respectively. The catalyst surface area and Pt:Sn surface area ratio was determined by anodic striping of an underpotential deposited Cu monolayer. The two deposition variants gave different catalyst surfaces: total area 233 and 76 cm{sup 2} mg{sup -1}, with Pt:Sn surface area ratio of 3.5:1 and 7.7:1 for surfactant and metal adsorption, respectively. Regarding electrocatalysis of ethanol oxidation, voltammetry and chronopotentiometry studies corroborated by direct ethanol fuel cell experiments using 0.5 M H{sub 2}SO{sub 4} as electrolyte, showed that due to a combination of higher catalyst load and Pt:Sn surface ratio, the graphite felt anodes prepared by the metal-adsorption variant gave better performance. The catalyzed graphite felt provided an extended reaction zone for ethanol electrooxidation and it gave higher catalyst mass specific peak power outputs compared to literature data obtained using gas diffusion anodes with carbon black supported Pt-Sn nanoparticles. (author)

  5. Host-Guest Recognition-Assisted Electrochemical Release: Its Reusable Sensing Application Based on DNA Cross Configuration-Fueled Target Cycling and Strand Displacement Reaction Amplification.

    Science.gov (United States)

    Chang, Yuanyuan; Zhuo, Ying; Chai, Yaqin; Yuan, Ruo

    2017-08-15

    In this work, an elegantly designed host-guest recognition-assisted electrochemical release was established and applied in a reusable electrochemical biosensor for the detection of microRNA-182-5p (miRNA-182-5p), a prostate cancer biomarker in prostate cancer, based on the DNA cross configuration-fueled target cycling and strand displacement reaction (SDR) amplification. With such a design, the single target miRNA input could be converted to large numbers of single-stranded DNA (S1-Trp and S2-Trp) output, which could be trapped by cucurbit[8]uril methyl viologen (CB-8-MV 2+ ) based on the host-guest recognition, significantly enhancing the sensitivity for miRNA detection. Moreover, the nucleic acids products obtained from the process of cycling amplification could be utilized sufficiently, avoiding the waste and saving the experiment cost. Impressively, by resetting a settled voltage, the proposed biosensor could release S1-Trp and S2-Trp from the electrode surface, attributing that the guest ion methyl viologen (MV 2+ ) was reduced to MV +· under this settled voltage and formed a more-stable CB-8-MV +· -MV +· complex. Once O 2 was introduced in this system, MV +· could be oxidized to MV 2+ , generating the complex of CB-8-MV 2+ for capturing S1-Trp and S2-Trp again in only 5 min. As a result, the simple and fast regeneration of biosensor for target detection was realized on the base of electrochemical redox-driven assembly and release, overcoming the challenges of time-consuming, burdensome operations and expensive experimental cost in traditional reusable biosensors and updating the construction method for a reusable bisensor. Furthermore, the biosensor could be reused for more than 10 times with a regeneration rate of 93.20%-102.24%. After all, the conception of this work provides a novel thought for the construction of effective reusable biosensor to detect miRNA and other biomarkers and has great potential application in the area requiring the release of

  6. mizuRoute version 1: A river network routing tool for a continental domain water resources applications

    Science.gov (United States)

    Mizukami, Naoki; Clark, Martyn P.; Sampson, Kevin; Nijssen, Bart; Mao, Yixin; McMillan, Hilary; Viger, Roland; Markstrom, Steven; Hay, Lauren E.; Woods, Ross; Arnold, Jeffrey R.; Brekke, Levi D.

    2016-01-01

    This paper describes the first version of a stand-alone runoff routing tool, mizuRoute. The mizuRoute tool post-processes runoff outputs from any distributed hydrologic model or land surface model to produce spatially distributed streamflow at various spatial scales from headwater basins to continental-wide river systems. The tool can utilize both traditional grid-based river network and vector-based river network data. Both types of river network include river segment lines and the associated drainage basin polygons, but the vector-based river network can represent finer-scale river lines than the grid-based network. Streamflow estimates at any desired location in the river network can be easily extracted from the output of mizuRoute. The routing process is simulated as two separate steps. First, hillslope routing is performed with a gamma-distribution-based unit-hydrograph to transport runoff from a hillslope to a catchment outlet. The second step is river channel routing, which is performed with one of two routing scheme options: (1) a kinematic wave tracking (KWT) routing procedure; and (2) an impulse response function – unit-hydrograph (IRF-UH) routing procedure. The mizuRoute tool also includes scripts (python, NetCDF operators) to pre-process spatial river network data. This paper demonstrates mizuRoute's capabilities to produce spatially distributed streamflow simulations based on river networks from the United States Geological Survey (USGS) Geospatial Fabric (GF) data set in which over 54 000 river segments and their contributing areas are mapped across the contiguous United States (CONUS). A brief analysis of model parameter sensitivity is also provided. The mizuRoute tool can assist model-based water resources assessments including studies of the impacts of climate change on streamflow.

  7. Hollow nanoporous covalent triazine frameworks via acid vapor-assisted solid phase synthesis for enhanced visible light photoactivity

    KAUST Repository

    Huang, Wei

    2016-04-11

    Herein, we report a novel trifluoromethanesulfonic acid vapor-assisted solid phase synthetic method to construct nanoporous covalent triazine frameworks with highly ordered hollow interconnected pores under mild reaction conditions. This unique solid state synthetic route allows not only the avoidance of undesired side reactions caused by traditional high temperature synthesis, but also the maintaining of defined and precise optical and electronic properties of the nonporous triazine frameworks. Promising photocatalytic activity of the polytriazine networks was demonstrated in the photoreduction reaction of 4-nitrophenol into 4-aminophenol under visible light irradiation.

  8. Hollow nanoporous covalent triazine frameworks via acid vapor-assisted solid phase synthesis for enhanced visible light photoactivity

    KAUST Repository

    Huang, Wei; Wang, Zi Jun; Ma, Beatriz Chiyin; Ghasimi, Saman; Gehrig, Dominik; Laquai, Fré dé ric; Landfester, Katharina; Zhang, Kai A. I.

    2016-01-01

    Herein, we report a novel trifluoromethanesulfonic acid vapor-assisted solid phase synthetic method to construct nanoporous covalent triazine frameworks with highly ordered hollow interconnected pores under mild reaction conditions. This unique solid state synthetic route allows not only the avoidance of undesired side reactions caused by traditional high temperature synthesis, but also the maintaining of defined and precise optical and electronic properties of the nonporous triazine frameworks. Promising photocatalytic activity of the polytriazine networks was demonstrated in the photoreduction reaction of 4-nitrophenol into 4-aminophenol under visible light irradiation.

  9. 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.

  10. 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.

  11. Innovative Sol-Gel Routes for the Bottom-up Preparation of Heterogeneous Catalysts.

    Science.gov (United States)

    Debecker, Damien P

    2017-12-11

    Heterogeneous catalysts can be prepared by different methods offering various levels of control on the final properties of the solid. In this account, we exemplify bottom-up preparation routes that are based on the sol-gel chemistry and allow to tailor some decisive properties of solid catalysts. First, an emulsion templating strategy is shown to lead to macrocellular self-standing monoliths with a macroscopic 3D structure. The latter can be used as catalyst or catalyst supports in flow chemistry, without requiring any subsequent shaping step. Second, the aerosol-assisted sol-gel process allows for the one-step and continuous production of porous mixed oxides. Tailored textural properties can be obtained together with an excellent control on composition and homogeneity. Third, the application of non-hydrolytic sol-gel routes, in the absence of water, leads to mixed oxides with outstanding textural properties and with peculiar surface chemistry. In all cases, the resulting catalytic performance can be correlated with the specificities of the preparation routes presented. This is exemplified in catalytic reactions in the fields of biomass conversion, petro chemistry, enantioselective organic synthesis, and air pollution mitigation. © 2017 The Chemical Society of Japan & Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Excitation functions of deuteron induced nuclear reactions on natMo up to 21 MeV. An alternative route for the production of 99mTc and 99Mo

    International Nuclear Information System (INIS)

    Sonck, M.; Hermanne, A.; Takacs, S.; Szelecsenyi, F.; Tarkanyi, F.

    1999-01-01

    Cross sections of deuteron induced nuclear reactions on natural molybdenum have been studied in the frame of a systematic investigation of charged particle induced nuclear reactions on metals for different applications. The excitation functions of 92m,95 Nb-, 93,94g,94m,95g,95m,96,99m Tc- and 99 Mo were measured up to 21 MeV deuteron energy by using stacked foil technique and activation method. The goal of this work was to study the production possibility of the medical important 94m,99m Tc- and 99 Mo-nuclides. Production of 99m Tc and 99 Mo is of importance for their use in nuclear medicine, whereas 94m Tc is of interest regarding quantification of kinetics of well-established 99m Tc-radiopharmaceuticals. The production possibilities of 99m Tc and 99 Mo above 20 MeV deuteron energies up to 50 MeV were estimated and was found that beside the proton induced reactions the deuteron induced reactions on enriched molybdenum target are very promising. (author)

  13. Photo-assisted cyanation of transition metal nitrates coupled with room temperature C-C bond cleavage of acetonitrile.

    Science.gov (United States)

    Zou, Shihui; Li, Renhong; Kobayashi, Hisayoshi; Liu, Juanjuan; Fan, Jie

    2013-03-07

    It is a challenge to use acetonitrile as a cyanating agent because of the difficulty in cleaving its C-CN bond. Herein, we report a mild photo-assisted route to conduct the cyanation of transition metal nitrates using acetonitrile as the cyanating agent coupled with room-temperature C-C bond cleavage. DFT calculations and experimental observations suggest a radical-involved reaction mechanism, which excludes toxicity from free cyanide ions.

  14. 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...

  15. A concise synthesis of benzimidazoles via the microwave-assisted one-pot batch reaction of amino acids up to a 10-g scale.

    Science.gov (United States)

    Peng, Pai; Xiong, Jin-Feng; Mo, Guang-Zhen; Zheng, Jia-Li; Chen, Ren-Hong; Chen, Xiao-Yun; Wang, Zhao-Yang

    2014-10-01

    An efficient method for the synthesis of aminomethyl benzimidazoles is developed by using a one-pot batch reaction between amino acids and o-phenylenediamines. This reaction proceeds smoothly in an unmodified household microwave oven, even though scale-up is to 10 g. A desirable method for the quick synthesis of benzimidazoles, which are used as a kind of important intermediates in drug synthesis, is provided by the scale-up utilization of amino acid resource.

  16. 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.

  17. An Efficient Procedure Based on a MW-Assisted Horner–Wadsworth-Emmons Reaction for the Synthesis of (Z-3,3-Trisubstituted-a,b-unsaturated Esters

    Directory of Open Access Journals (Sweden)

    Ornella Azzolina

    2010-08-01

    Full Text Available A microwave-assisted HWE olefination process of readily accessible aryl-alkyl ketones has been developed to provide a rapid access to (Z-3,3-trisubstituted-α,β-unsaturated methyl esters, key building blocks for the synthesis of biologically active compounds.

  18. Synthesis and Characterization of Polyol-Assisted Nano Cu0.2Ni0.2Sn0.2Ba0.4 Fe2O4 by a Wet Hydroxyl Route

    Science.gov (United States)

    Pavithradevi, S.; Suriyanarayanan, N.; Boobalan, T.; Velumani, S.; Chandramohan, M.; Manivel Raja, M.

    2017-08-01

    Nanocrystalline spinel ferrite of composition Cu0.2Ni0.2Sn0.2Ba0.4 Fe2O4 has been synthesized by a wet hydroxyl chemical route in ethylene glycol as chelating agent and sodium hydroxide as precipitator at pH 8. Ethylene glycol has been used as the medium which serves as the solvent as well as a complexing agent. The synthesized particles are annealed at temperatures of 350°C, 700°C, and 1050°C. Thermogravimetric (TG) analysis confirms that at 240°C, ethylene glycol has evaporated completely, and a stable phase is formed above 670°C. Fourier transform infrared (FT-IR) spectroscopy of mixed Cu0.2Ni0.2Sn0.2Ba0.4 ferrite nanoparticles like as synthesized and annealed at 1050°C are recorded between 400 cm-1 and 4000 cm-1. FT-IR appraises the structural formation of Cu0.2Ni0.2Sn0.2Ba0.4 Fe2O4 between the as-synthesized sample and the sample annealed at 1050°C. Structural characterizations of all the samples are carried out by x-ray diffraction (XRD) technique. XRD reveals that the particle size increases with the increase in annealing temperatures. Transmission electron microscopy (TEM) and scanning electron microscopy (SEM) confirms that the particles are flaky and spherical with the crystallite size in the range of 11-27 nm. The decrement of dielectric properties, like dielectric constant and dielectric loss, with the increment of frequency as seen in all the samples is an usual dielectric behavior of spinel ferrites. The lack of net magnetization is noticed immediately when the applied magnetic field is removed which prompts superparamagnetic behavior, as seen in all the samples.

  19. 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.

  20. 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...

  1. Ultrasound-assisted phase-transfer catalysis method in an aqueous medium to promote the Knoevenagel reaction: advantages over the conventional and microwave-assisted solvent-free/catalyst-free method.

    Science.gov (United States)

    De-la-Torre, Pedro; Osorio, Edison; Alzate-Morales, Jans H; Caballero, Julio; Trilleras, Jorge; Astudillo-Saavedra, Luis; Brito, Iván; Cárdenas, Alejandro; Quiroga, Jairo; Gutiérrez, Margarita

    2014-09-01

    Given the broad spectrum of uses of acrylonitrile derivatives as fluorescent probes, AChE inhibitors, and others, it is necessary to find easy, efficient and simple methods to synthesize and diversify these compounds. We report the results of a comparative study of the effects of three techniques on the reactions between heterocyclic aldehydes and 2-(benzo[d]thiazol-2-yl)acetonitrile: stirring; ultrasound coupled to PTC conditions (US-PTC); and MW irradiation (MWI) under solvent and catalyst-free conditions. The effects of conditions on reaction parameters were evaluated and compared in terms of reaction time, yield, purity and outcomes. The US-PTC method is more efficient than the MWI and conventional methods. The reaction times were considerably shorter, with high yields (>90%) and good levels of purity. In addition, X-ray diffraction analysis and quantum mechanical calculations, at the level of density functional theory (DFT), ratify obtaining acrylonitrile isomers with E configurations. The crystal structure of 3c is stabilized by weak C-Ho⋯N intermolecular interactions (Ho⋯NC=2.45 Å, Co⋯NC=3.348(3) Å, Ho⋯NC=162°), forming centrosymmetric ring R2(2) (20) along the crystallographic a axis. Copyright © 2014 Elsevier B.V. All rights reserved.

  2. 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...

  3. Effect of FeH-zeolite structure and Al-Lewis sites on N2O decomposition and NO/NO2-assisted reaction

    Czech Academy of Sciences Publication Activity Database

    Kaucký, Dalibor; Sobalík, Zdeněk; Schwarze, Michael; Vondrová, Alena; Wichterlová, Blanka

    2006-01-01

    Roč. 238, č. 2 (2006), s. 293-300 ISSN 0021-9517 R&D Projects: GA ČR GP104/02/D124; GA AV ČR 1ET400400413 Institutional research plan: CEZ:AV0Z40400503 Keywords : N2O decomposition * NO/NO2 assistance * Fe-zeolites * Fe-ferrierite Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 4.533, year: 2006

  4. Ultrasound-assisted synthesis of β-amino ketones via a Mannich reaction catalyzed by Fe3O4 magnetite nanoparticles as an efficient, recyclable and heterogeneous catalyst

    Directory of Open Access Journals (Sweden)

    Naghi Saadatjoo

    2017-02-01

    The present methodology offers several advantages, such as good yields, short reaction times and a recyclable catalyst with a very easy work up. In addition, the obtained results indicated that MNPs can be used as an effective and inexpensive catalyst for stereoselective synthesis of β-amino carbonyl by a one-pot three component condensation of aldehydes, ketones and amines.

  5. CATALYST-FREE REACTIONS UNDER SOLVENT-FEE CONDITIONS: MICROWAVE-ASSISTED SYNTHESIS OF HETEROCYCLIC HYDRAZONES BELOW THE MELTING POINT OF NEAT REACTANTS

    Science.gov (United States)

    The reaction of neat 5- or 8-oxobenzopyran-2(1H)-ones with a variety of aromatic and heteroaromatic hydrazines are remarkable accelerated upon irradiation in a household microwave oven in the absence of any catalyst, solid support or solvent thus providing an environmentally frie...

  6. Synthesis of unnatural amino acids via microwave-assisted regio-selective one-pot multi-component reactions of sulfamidates

    Science.gov (United States)

    Synthesis of triazole-based unnatural amino acids, triazole bisaminoacids and β-amino triazole has been described via stereo and regioselective one-pot multi-component reaction of sulfamidates, sodium azide, and alkynes under MW irradiation conditions. The developed method is app...

  7. Nature-assisted rehabilitation for reactions to severe stress and/or depression in a rehabilitation garden: long-term follow-up including comparisons with a matched population-based reference cohort.

    Science.gov (United States)

    Währborg, Peter; Petersson, Ingemar F; Grahn, Patrik

    2014-03-01

    To determine the effect of a nature-assisted rehabilitation programme in a group of patients with reactions to severe stress and/or mild to moderate depression. Changes in sick-leave status and healthcare consumption in these patients were compared with those in a matched population-based reference cohort (treatment as usual). Retrospective cohort study with a matched reference group from the general population. A total of 118 participants referred to a nature-assisted rehabilitation programme, and 678 controls recruited from the Skåne Health Care Register. For both groups, information on sick leave was extracted from the National Social Insurance Register and on healthcare consumption data from the Skåne Health Care Register. The interventional rehabilitation programme was designed as a multimodal programme involving professionals from horticulture and medicine. The programme was conducted in a rehabilitation garden, designed especially for this purpose. A significant reduction in healthcare consumption was noted among participants in the programme compared with the reference population. The main changes were a reduction in outpatient visits to primary healthcare and a reduction in inpatient psychiatric care. No significant difference in sick-leave status was found. A structured, nature-based rehabilitation programme for patients with reactions to severe stress and/or depression could be beneficial, as reflected in reduced healthcare consumption.

  8. 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.

  9. Preparation of Ba1-xSrxWO4 and Ba1-xCaxWO4 films on tungsten plate by mechanically assisted solution reaction at room temperature

    International Nuclear Information System (INIS)

    Rangappa, Dinesh; Fujiwara, Takeshi; Watanabe, Tomoaki; Yoshimura, Masahiro

    2008-01-01

    Preparation of the alkaline earth tungstate films such as Ba 1-x Sr x WO 4 and Ba 1-x Ca x WO 4 on the tungsten substrate was studied with a simple solution process assisted with the ball rotation at room temperature. The solid solution formation and limitations, the effect of oxidizing agent H 2 O 2 and alkaline earth ions concentration on the dissolution of W substrate and the growth of Ba 1-x Sr x WO 4 and Ba 1-x Ca x WO 4 films were studied in detail. The ball rotation assistance plays a very important role to enhance the dissolution of the W substrate and mass transport of the reactant species such as alkaline earth ions and WO 4 2- ions onto the solid/solution interface region, where precipitation occurs. Therefore, the rate of film formation was accelerated by the ball rotation assistance to the reaction system. Ba-rich Ba 1-x Sr x WO 4 and Ba 1-x Ca x WO 4 films were formed without high energy or high temperature treatment

  10. Indoor Semantic Modelling for Routing: The Two-Level Routing Approach for Indoor Navigation

    Directory of Open Access Journals (Sweden)

    Liu Liu

    2017-11-01

    detailed levels. • On the conceptual level, it supports routing on a logical network and assists the derivation of a conceptual path (i.e., logical path for a user in terms of space sequence. Routing criteria are designed based on the INSM semantics of spaces, which can generate logical paths similar to human wayfinding results such as minimizing VerticalUnit or HorizontalConnector. • On the detailed level, it considers the size of users and results in obstacle-avoiding paths. By using this approach, geometric networks can be generated to avoid obstacles for the given users and accessible paths are flexibly provided for user demands. This approach can process changes of user size more efficiently, in contrast to routing on a complete geometric network. • It supports routing on both the logical and the geometric networks, which can generate geometric paths based on user-specific logical paths, or re-compute logical paths when geometric paths are inaccessible. This computation method is very useful for complex buildings. The two-level routing approach can flexibly provide logical and geometric paths according to user preferences and sizes, and can adjust the generated paths in limited time. Based on the two-level routing approach, this thesis also provides a vision on possible cooperation with other methods. A potential direction is to design more routing options according to other indoor scenarios and user preferences. Extensions of the two-level routing approach, such as other types of semantics, multi-level networks and dynamic obstacles, will make it possible to deal with other routing cases. Last but not least, it is also promising to explore its relationships with indoor guidance, different building subdivisions and outdoor navigation.

  11. Guidelines for applying criteria to designate routes for transporting hazardous materials. Final report

    International Nuclear Information System (INIS)

    1989-07-01

    These guidelines were prepared to assist State and local officials in the analysis of alternate routes to be used by highway vehicles transportating hazardous materials. A methodology for assessing comparative risks of routing alternatives is discussed and demonstrated through a hypothetical example. Mathematical models are provided for situations in which measured local data may not be easily obtained or adequate

  12. 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.

  13. A simple route to vertical array of quasi-1D ZnO nanofilms on FTO surfaces: 1D-crystal growth of nanoseeds under ammonia-assisted hydrolysis process

    Directory of Open Access Journals (Sweden)

    Abd Rahman Mohd Yusri

    2011-01-01

    Full Text Available Abstract A simple method for the synthesis of ZnO nanofilms composed of vertical array of quasi-1D ZnO nanostructures (quasi-NRs on the surface was demonstrated via a 1D crystal growth of the attached nanoseeds under a rapid hydrolysis process of zinc salts in the presence of ammonia at room temperature. In a typical procedure, by simply controlling the concentration of zinc acetate and ammonia in the reaction, a high density of vertically oriented nanorod-like morphology could be successfully obtained in a relatively short growth period (approximately 4 to 5 min and at a room-temperature process. The average diameter and the length of the nanostructures are approximately 30 and 110 nm, respectively. The as-prepared quasi-NRs products were pure ZnO phase in nature without the presence of any zinc complexes as confirmed by the XRD characterisation. Room-temperature optical absorption spectroscopy exhibits the presence of two separate excitonic characters inferring that the as-prepared ZnO quasi-NRs are high-crystallinity properties in nature. The mechanism of growth for the ZnO quasi-NRs will be proposed. Due to their simplicity, the method should become a potential alternative for a rapid and cost-effective preparation of high-quality ZnO quasi-NRs nanofilms for use in photovoltaic or photocatalytics applications. PACS: 81.07.Bc; 81.16.-c; 81.07.Gf.

  14. l-Glutamic acid assisted eco-friendly one-pot synthesis of sheet-assembled platinum-palladium alloy networks for methanol oxidation and oxygen reduction reactions.

    Science.gov (United States)

    Shi, Ya-Cheng; Mei, Li-Ping; Wang, Ai-Jun; Yuan, Tao; Chen, Sai-Sai; Feng, Jiu-Ju

    2017-10-15

    In this work, bimetallic platinum-palladium sheet-assembled alloy networks (PtPd SAANs) were facilely synthesized by an eco-friendly one-pot aqueous approach under the guidance of l-glutamic acid at room temperature, without any additive, seed, toxic or organic solvent involved. l-Glutamic acid was served as the green shape-director and weak-stabilizing agent. A series of characterization techniques were employed to examine the morphology, structure and formation mechanism of the product. The architectures exhibited improved electrocatalytic activity and durable ability toward methanol oxidation reaction (MOR) and oxygen reduction reaction (ORR) in contrast with commercial Pt black and Pd black catalysts. This is ascribed to the unique structures of the obtained PtPd SAANs and the synergistic effects of the bimetals. These results demonstrate the potential application of the prepared catalyst in fuel cells. Copyright © 2017 Elsevier Inc. All rights reserved.

  15. Furfural Production from d-Xylose and Xylan by Using Stable Nafion NR50 and NaCl in a Microwave-Assisted Biphasic Reaction

    Directory of Open Access Journals (Sweden)

    Sarah Le Guenic

    2016-08-01

    Full Text Available Pentose dehydration and direct transformation of xylan into furfural were performed in a water-cyclopentyl methyl ether (CPME biphasic system under microwave irradiation. Heated up between 170 and 190 °C in the presence of Nafion NR50 and NaCl, d-xylose, l-arabinose and xylan gave furfural with maximum yields of 80%, 42% and 55%, respectively. The influence of temperature and reaction time on the reaction kinetics was discussed. This study was also completed by the survey of different reactant ratios, such as organic layer-water or catalyst-inorganic salt ratios. The exchange between proton and cation induced by an excess of NaCl was monitored, and a synergetic effect between the remaining protons and the released HCl was also discovered.

  16. Furfural Production from d-Xylose and Xylan by Using Stable Nafion NR50 and NaCl in a Microwave-Assisted Biphasic Reaction.

    Science.gov (United States)

    Le Guenic, Sarah; Gergela, David; Ceballos, Claire; Delbecq, Frederic; Len, Christophe

    2016-08-22

    Pentose dehydration and direct transformation of xylan into furfural were performed in a water-cyclopentyl methyl ether (CPME) biphasic system under microwave irradiation. Heated up between 170 and 190 °C in the presence of Nafion NR50 and NaCl, d-xylose, l-arabinose and xylan gave furfural with maximum yields of 80%, 42% and 55%, respectively. The influence of temperature and reaction time on the reaction kinetics was discussed. This study was also completed by the survey of different reactant ratios, such as organic layer-water or catalyst-inorganic salt ratios. The exchange between proton and cation induced by an excess of NaCl was monitored, and a synergetic effect between the remaining protons and the released HCl was also discovered.

  17. 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

  18. 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

  19. The synthesis of α-aryl-α-aminophosphonates and α-aryl-α-aminophosphine oxides by the microwave-assisted Pudovik reaction

    Directory of Open Access Journals (Sweden)

    Erika Bálint

    2017-01-01

    Full Text Available A family of α-aryl-α-aminophosphonates and α-aryl-α-aminophosphine oxides was synthesized by the microwave-assisted solvent-free addition of dialkyl phosphites and diphenylphosphine oxide, respectively, to imines formed from benzaldehyde derivatives and primary amines. After optimization, the reactivity was mapped, and the fine mechanism was evaluated by DFT calculations. Two α-aminophosphonates were subjected to an X-ray study revealing a racemic dimer formation made through a N–H···O=P intermolecular hydrogen bridges pair.

  20. Master curves for the sulphur assisted crosslinking reaction of natural rubber in the presence of nano- and nano-structured sp2 carbon allotropes

    Directory of Open Access Journals (Sweden)

    S. Musto

    2017-06-01

    Full Text Available In this paper, master curves are reported for the crosslinking of a diene rubber with a sulphur based system in the presence of either nano- or nano-structured carbon allotropes, such as carbon nanotubes (CNT, a nanosized graphite with high surface area (HSAG and carbon black (CB. Poly(1,4-cis-isoprene from Hevea Brasiliensis was the diene rubber and crosslinking was performed in temperatures ranging from 151 to 180 °C, with carbon allotropes below and above their percolation threshold. Such carbon allotropes were characterized by different aspect ratio, surface area and pH. However, in the crosslinking reaction, they revealed common behaviour. In fact, the specific interfacial area could be used to correlate crosslinking parameters, such as induction time (ts1 and activation energy (Ea calculated by applying the autocatalytic model. Monotonous decrease of ts1 and increase of Ea were observed, with points lying on master curves, regardless of the nature of the carbon allotropes. Remarkable differences were however observed in the structure of the crosslinking network: when the carbon allotrope was above the percolation threshold much larger crosslinking density was obtained in the presence of CNT whereas composites based on HSAG became soluble in hydrocarbon solvent, after the reaction with a thiol. Proposed explanation of these results is based on the reactivity of carbon allotropes with sulphur and sulphur based compounds, demonstrated through the reaction of 1-dodecanethiol and sulphur with CNT and HSAG and with a model substrate such as anthracene.

  1. Microwave assisted green synthesis and characterizations of noble metal nanoparticles and their roles as catalysts in organic reduction reactions and anticancer agent

    Science.gov (United States)

    Francis, Sijo; Koshy, Ebey P.; Mathew, Beena

    2018-04-01

    Nanomaterials are interesting chemicals that uncover the explorations and expectations of decades. The report suggests environmentally benevolent and easy route for the synthesis of noble metal nanoparticles. Personnel, laboratory and ecological benefits of the synthesized nanoparticles are demonstrated herein. The aqueous extract from the leaves of Litchi chinensis Sonn is performed as the alternative reducing agent. The microwave activated silver and gold nanoparticles have spherical geometries with crystalline essence. X-ray diffraction technique witnessed the face centered cubic lattice for the nano silver and gold particles that preferentially oriented towards the (111) plane. The reduction of nitro anilines is performed to elucidate the heterogeneous catalytic power of the nanoparticles. The nano catalyst is a potential candidate to meet the challenges raised from organic pollutant dye that cause environmental contamination. The chemical stability, low-cost factor and plant based origin of the new nanoparticles are admired. The multitudes of health hazards especially human carcinoma can be effectively inhibited by the silver and gold nanoparticles. The leaf extract, silver and gold nanoparticles showed IC50 values 66.56 ± 0.80, 23.55 ± 0.43 and 20.38 ± 0.41 μg ml‑1 respectively against the human lung adenocarcinoma cell lines A549 determined using the MTT dye conversion assay.

  2. Synthesis, characterization and catalytic performance of mixed nanoferrites submitted to transesterification and esterification reaction using methyl and ethyl route for biodiesel production; Sintese, caracterizacao e performance catalitica de nanoferritas mistas submetidas a reacao de transesterificacao e esterificacao via rota metilica e etilica para biodiesel

    Energy Technology Data Exchange (ETDEWEB)

    Dantas, Joelda; Leal, Elvia; Mapossa, Antonio Benjamim; Silva, Adriano Sant' Ana; Costa, Ana Cristina Figueiredo de Melo, E-mail: joeldadantas@yahoo.com.br, E-mail: elvialeal@gmail.com, E-mail: mapossabenjox@gmail.com, E-mail: adriano_santana@yahoo.com.br, E-mail: ana.cristina@pq.cnpq.br [Universidade Federal de Campina Grande (LabSMaC/UAEMa/UFCG), PB (Brazil). Lab. de Sintese de Materiais Ceramicos

    2016-10-15

    The mixed nanoferrites of Ni{sub 0.5}Zn{sub 0.5}Fe{sub 2}O{sub 4} and Ni{sub 0.2}Cu{sub 0.3}Zn{sub 0.5}Fe{sub 2}O{sub 4} were synthesized by combustion reaction using urea as fuel and a conical reactor as heating source in batches of 10 g, and then tested as heterogeneous nanocatalysts in the transesterification and esterification reaction of soya bean oil using the methyl and ethyl routes to biodiesel production. During the synthesis the time and temperature of the reactions were measured, and the evolved gases and the color of the emitted flames were observed. The samples were characterized by XRD, EDX, FTIR, SEM/EDS, BET and gas chromatography. The reaction tests were carried out with 10 g of oil for 1 h, oil:alcohol molar ratio of 1:12, 2 % (w/w) of catalyst, and conducted at 180 °C. The XRD patterns and the FTIR spectra revealed the presence of the inverse spinel phase type B(AB){sub 2}O{sub 4}. The morphology showed the formation of agglomerates with fragile morphology and high surface area. The chromatographic analysis produced excellent results in the esterification reactions for both samples in the tested conditions, with special emphasis on Ni{sub 0.5}Zn{sub 0.5}Fe{sub 2}O{sub 4}, whose conversions were of 91.4 % in methyl esters and of 77.8 % in ethyl esters, while the Ni{sub 0.2}Cu{sub 0.3}Zn{sub 0.5}Fe{sub 2}O{sub 4} sample showed conversion of 75.1 and 65.1 %, respectively. The conversions in the methyl and ethyl transesterification were of 14 and 2 % of the Ni{sub 0.5}Zn{sub 0.5}Fe{sub 2}O{sub 4} sample, and of 11 and 3 % for the Ni{sub 0.2}Cu{sub 0.3}Zn{sub 0.5}Fe{sub 2}O{sub 4} sample. (author)

  3. Nucleotide Selectivity in Abiotic RNA Polymerization Reactions

    Science.gov (United States)

    Coari, Kristin M.; Martin, Rebecca C.; Jain, Kopal; McGown, Linda B.

    2017-09-01

    In order to establish an RNA world on early Earth, the nucleotides must form polymers through chemical rather than biochemical reactions. The polymerization products must be long enough to perform catalytic functions, including self-replication, and to preserve genetic information. These functions depend not only on the length of the polymers, but also on their sequences. To date, studies of abiotic RNA polymerization generally have focused on routes to polymerization of a single nucleotide and lengths of the homopolymer products. Less work has been done the selectivity of the reaction toward incorporation of some nucleotides over others in nucleotide mixtures. Such information is an essential step toward understanding the chemical evolution of RNA. To address this question, in the present work RNA polymerization reactions were performed in the presence of montmorillonite clay catalyst. The nucleotides included the monophosphates of adenosine, cytosine, guanosine, uridine and inosine. Experiments included reactions of mixtures of an imidazole-activated nucleotide (ImpX) with one or more unactivated nucleotides (XMP), of two or more ImpX, and of XMP that were activated in situ in the polymerization reaction itself. The reaction products were analyzed using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) to identify the lengths and nucleotide compositions of the polymerization products. The results show that the extent of polymerization, the degree of heteropolymerization vs. homopolymerization, and the composition of the polymeric products all vary among the different nucleotides and depend upon which nucleotides and how many different nucleotides are present in the mixture.

  4. Nucleotide Selectivity in Abiotic RNA Polymerization Reactions.

    Science.gov (United States)

    Coari, Kristin M; Martin, Rebecca C; Jain, Kopal; McGown, Linda B

    2017-09-01

    In order to establish an RNA world on early Earth, the nucleotides must form polymers through chemical rather than biochemical reactions. The polymerization products must be long enough to perform catalytic functions, including self-replication, and to preserve genetic information. These functions depend not only on the length of the polymers, but also on their sequences. To date, studies of abiotic RNA polymerization generally have focused on routes to polymerization of a single nucleotide and lengths of the homopolymer products. Less work has been done the selectivity of the reaction toward incorporation of some nucleotides over others in nucleotide mixtures. Such information is an essential step toward understanding the chemical evolution of RNA. To address this question, in the present work RNA polymerization reactions were performed in the presence of montmorillonite clay catalyst. The nucleotides included the monophosphates of adenosine, cytosine, guanosine, uridine and inosine. Experiments included reactions of mixtures of an imidazole-activated nucleotide (ImpX) with one or more unactivated nucleotides (XMP), of two or more ImpX, and of XMP that were activated in situ in the polymerization reaction itself. The reaction products were analyzed using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) to identify the lengths and nucleotide compositions of the polymerization products. The results show that the extent of polymerization, the degree of heteropolymerization vs. homopolymerization, and the composition of the polymeric products all vary among the different nucleotides and depend upon which nucleotides and how many different nucleotides are present in the mixture.

  5. 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...

  6. 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

  7. 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

  8. Electrochemical performance of Li4Mn5O12 nano-crystallites prepared by spray-drying-assisted solid state reactions

    International Nuclear Information System (INIS)

    Jiang, Y.P.; Xie, J.; Cao, G.S.; Zhao, X.B.

    2010-01-01

    Nanosized Li 4 Mn 5 O 12 has been synthesized by a spray-drying-assisted solid state method. The effect of spray drying and drying temperature on the microstructure and electrochemical performance of the final products has been investigated. The microstructure of the products has been characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM) and transmission electron microscopy (TEM). The electrochemical performance of the products has been studied by galvanostatic cycling, cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). It has been found that the products prepared with a spray-drying pretreatment of the precursor exhibit a smaller grain size and a narrower size distribution than that prepared without the pretreatment. Among the three samples with a precursor pretreatment, that pretreated at 250 o C shows the best electrochemical performance due to the smallest grain size of below 50 nm and the narrowest size distribution.

  9. Heterojunction-Assisted Co3 S4 @Co3 O4 Core-Shell Octahedrons for Supercapacitors and Both Oxygen and Carbon Dioxide Reduction Reactions.

    Science.gov (United States)

    Yan, Yibo; Li, Kaixin; Chen, Xiaoping; Yang, Yanhui; Lee, Jong-Min

    2017-12-01

    Expedition of electron transfer efficiency and optimization of surface reactant adsorption products desorption processes are two main challenges for developing non-noble catalysts in the oxygen reduction reaction (ORR) and CO 2 reduction reaction (CRR). A heterojunction prototype on Co 3 S 4 @Co 3 O 4 core-shell octahedron structure is established via hydrothermal lattice anion exchange protocol to implement the electroreduction of oxygen and carbon dioxide with high performance. The synergistic bifunctional catalyst consists of p-type Co 3 O 4 core and n-type Co 3 S 4 shell, which afford high surface electron density along with high capacitance without sacrificing mechanical robustness. A four electron ORR process, identical to the Pt catalyzed ORR, is validated using the core-shell octahedron catalyst. The synergistic interaction between cobalt sulfide and cobalt oxide bicatalyst reduces the activation energy to convert CO 2 into adsorbed intermediates and hereby enables CRR to run at a low overpotential, with formate as the highly selective main product at a high faraday efficiency of 85.3%. The remarkable performance can be ascribed to the synergistic coupling effect of the structured co-catalysts; heterojunction structure expedites the electron transfer efficiency and optimizes surface reactant adsorption product desorption processes, which also provide theoretical and pragmatic guideline for catalyst development and mechanism explorations. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Generalizable, Electroless, Template-Assisted Synthesis and Electrocatalytic Mechanistic Understanding of Perovskite LaNiO3 Nanorods as Viable, Supportless Oxygen Evolution Reaction Catalysts in Alkaline Media.

    Science.gov (United States)

    McBean, Coray L; Liu, Haiqing; Scofield, Megan E; Li, Luyao; Wang, Lei; Bernstein, Ashley; Wong, Stanislaus S

    2017-07-26

    The oxygen evolution reaction (OER) is a key reaction for water electrolysis cells and air-powered battery applications. However, conventional metal oxide catalysts, used for high-performing OER, tend to incorporate comparatively expensive and less abundant precious metals such as Ru and Ir, and, moreover, suffer from poor stability. To attempt to mitigate for all of these issues, we have prepared one-dimensional (1D) OER-active perovskite nanorods using a unique, simple, generalizable, and robust method. Significantly, our work demonstrates the feasibility of a novel electroless, seedless, surfactant-free, wet solution-based protocol for fabricating "high aspect ratio" LaNiO 3 and LaMnO 3 nanostructures. As the main focus of our demonstration of principle, we prepared as-synthesized LaNiO 3 rods and correlated the various temperatures at which these materials were annealed with their resulting OER performance. We observed generally better OER performance for samples prepared with lower annealing temperatures. Specifically, when annealed at 600 °C, in the absence of a conventional conductive carbon support, our as-synthesized LaNiO 3 rods not only evinced (i) a reasonable level of activity toward OER but also displayed (ii) an improved stability, as demonstrated by chronoamperometric measurements, especially when compared with a control sample of commercially available (and more expensive) RuO 2 .

  11. Preparation of Nd-doped barium cerate through different routes

    DEFF Research Database (Denmark)

    Chen, F.L.; Toft Sørensen, O.; Meng, G.Y.

    1997-01-01

    BaCe0.9Nd0.1O3-delta was prepared through different routes: oxalate coprecipitation (OF), carbonate-oxide mixed by ball-milling (COB) and carbonate-oxide mixed by mortar/pestle (COM). The reaction process studied by DTA-TG and XRD showed that calcination of the precursor powders at T greater than...

  12. Competitive sustainability of a transport route in the transport service market

    OpenAIRE

    Poletan Jugović, Tanja; Šimić Hlača, Marija; Žgaljić, Dražen

    2014-01-01

    In order for the particular transport route and entities in the production of a transport service on that route to maintain their position in the transport service market, they have to ensure efficiency, orientation towards service users, rationality, environmental friendliness and quality dominance of an offered service. User orientation and flexible reaction to market demands create preconditions for the establishment of a competitive and attractive transport route and accompanying transpor...

  13. Isotopic Exchange Reaction Assisted with Cu (I) generated ''in situ'' For Synthesis of Ready-to-Use for on-the-spot Formulation of [131 I] Iodobenzyl Derivatives

    International Nuclear Information System (INIS)

    Abudaia, J.A.; Suliman, M.O.

    2007-01-01

    It has been examined that meta-Iodobenzylguanidine (m-IBG), para-Iodoamphetamine (p-IPA) and orth-Iodohippuric acid (o-IHA) are three commonly used Iodobenzyl derivative compounds, and can be formulated as Ready-to-Use Kits for on-the-spot labeling catalyzed with copper ion Cu+ (I) generated ''In Situ''. The labeling procedure efficiently has been established within 30 min of heating using an autoclave, 20 min. and 90 min. using dry heating block respectively. Isotopic exchange reaction with Iodine-131 radioactive of those three Ready-to-Use Kits has led to Radiochemical Purity ''RCP'' equals to 98%, > 98%, and almost 99%, and Radiochemical Yield ''RCY'' > 97%, >93% and > 98% respectively. Attention was paid to the Radiochemical Stability of those three Iodobenzyl derivatives for a period time of preservation at low temperature. As a result, this gave evidence that such Radiopharmaceuticals could be used as Ready-to-Use products at different times of preservations.

  14. A versatile route to hybrid open-framework materials | Ayi | Global ...

    African Journals Online (AJOL)

    The isolation of the intermediate phase and its reaction with metal ions to form open framework solids has been explored and it has proven a facile route of synthesizing inorganic-organic hybrid materials with open pores. Here the amine phosphate route of templating inorganic open-framework materials has been reviewed ...

  15. The International Humanitarian Response to the Refugee Crisis Along the Balkan Route in the View of Strategies of International Organizations

    Directory of Open Access Journals (Sweden)

    Latifi Veton

    2017-06-01

    Full Text Available Being one of the largest movements of displaced people through European borders since World War Two, the Syrian refugee crisis of 2015 and 2016, tested the coordination of the states and international organizations, and as well as the strategies for response of the latter to such enormous fluxes of displaced people along the Balkan corridor. The quick on-time reaction of the specialized humanitarian international organizations made significant achievements by the international organizations in terms of humanitarian assistance for the refugees and support for the governments of the region. Their approach mainly sought to create a partnership with the governments of the Balkan route in handling the serious humanitarian challenges (with a different strategy compared to other experiences, mainly this time through providing assistance and protection to the refugees throughout the corridor of the refugee crisis, it showed how important is such coordination at the end, with an aim to avoid further human catastrophes along refugee routes, and to avoid major security repercussions for the countries of the region.

  16. 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...

  17. 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...

  18. 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.

  19. 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.

  20. Microwave-Assisted Synthesis of Reduced Graphene Oxide/SnO2 Nanocomposite for Oxygen Reduction Reaction in Microbial Fuel Cells.

    Science.gov (United States)

    Garino, Nadia; Sacco, Adriano; Castellino, Micaela; Muñoz-Tabares, José Alejandro; Chiodoni, Angelica; Agostino, Valeria; Margaria, Valentina; Gerosa, Matteo; Massaglia, Giulia; Quaglio, Marzia

    2016-02-01

    We report on an easy, fast, eco-friendly, and reliable method for the synthesis of reduced graphene oxide/SnO2 nanocomposite as cathode material for application in microbial fuel cells (MFCs). The material was prepared starting from graphene oxide that has been reduced to graphene during the hydrothermal synthesis of the nanocomposite, carried out in a microwave system. Structural and morphological characterizations evidenced the formation of nanocomposite sheets, with SnO2 crystals of few nanometers integrated in the graphene matrix. Physico-chemical analysis revealed the formation of SnO2 nanoparticles, as well as the functionalization of the graphene by the presence of nitrogen atoms. Electrochemical characterizations put in evidence the ability of such composite to exploit a cocatalysis mechanism for the oxygen reduction reaction, provided by the presence of both SnO2 and nitrogen. In addition, the novel composite catalyst was successfully employed as cathode in seawater-based MFCs, giving electrical performances comparable to those of reference devices employing Pt as catalyst.

  1. 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,

  2. Ultrasonic-assisted synthesis of monodisperse single-crystalline silver nanoplates and gold nanorings.

    Science.gov (United States)

    Jiang, Li-Ping; Xu, Shu; Zhu, Jian-Min; Zhang, Jian-Rong; Zhu, Jun-Jie; Chen, Hong-Yuan

    2004-09-20

    A simple sonochemical route was developed for the crystal growth of uniform silver nanoplates and ringlike gold nanocrystals in a N,N-dimethylformamide solution. The platelike structures were generated from the selective growth on different crystal planes in the presence of poly(vinylpyrrolidone) and the ultrasonic-assisted Ostwald ripening processes. The silver nanoplates in solution served as the templates for the synthesis of ringlike gold crystals via a displacement reaction. Both the silver nanoplates and gold nanorings were highly oriented single crystals with (111) planes as the basal planes. Copyright 2004 American Chemical Society

  3. 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...

  4. 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...

  5. A solvent evaporation route towards fabrication of hierarchically porous ZSM-11 with highly accessible mesopores

    DEFF Research Database (Denmark)

    Song, Wen; Liu, Zhiting; Liu, Liping

    2015-01-01

    A route to generate hierarchically porous zeolite ZSM-11 has been paved via solvent evaporation induced self-assembly assisted by hexadecyltrimethoxysilane to produce a preformed dry gel, followed by its subsequent transformation into zeolite via steam-assisted-crystallization. The crystallization...

  6. An electrochemical impedance biosensor for Hg2+ detection based on DNA hydrogel by coupling with DNAzyme-assisted target recycling and hybridization chain reaction.

    Science.gov (United States)

    Cai, Wei; Xie, Shunbi; Zhang, Jin; Tang, Dianyong; Tang, Ying

    2017-12-15

    In this work, an electrochemical impedance biosensor for high sensitive detection of Hg 2+ was presented by coupling with Hg 2+ -induced activation of Mg 2+ -specific DNAzyme (Mg 2+ -DNAzyme) for target cycling and hybridization chain reaction (HCR) assembled DNA hydrogel for signal amplification. Firstly, we synthesized two different copolymer chains P1 and P2 by modifying hairpin DNA H3 and H4 with acrylamide polymer, respectively. Subsequently, Hg 2+ was served as trigger to activate the Mg 2+ -DNAzyme for selectively cleavage ribonucleobase-modified substrate in the presence of Mg 2+ . The partial substrate strand could dissociate from DNAzyme structure, and hybridize with capture probe H1 to expose its concealed sequence for further hybridization. With the help of the exposed sequence, the HCR between hairpin DNA H3 and H4 in P1 and P2 was initiated, and assembled a layer of DNA cross-linked hydrogel on the electrode surface. The formed non-conductive DNA hydrogel film could greatly hinder the interfacial electronic transfer which provided a possibility for us to construct a high sensitive impedance biosensor for Hg 2+ detection. Under the optimal conditions, the impedance biosensor showed an excellent sensitivity and selectivity toward Hg 2+ in a concentration range of 0.1pM - 10nM with a detection limit of 0.042pM Moreover, the real sample analysis reveal that the proposed biosensor is capable of discriminating Hg 2+ ions in reliable and quantitative manners, indicating this method has a promising potential for preliminary application in routine tests. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. 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

  8. Route and landmark selection tool (RULST) : user's manual.; TOPICAL

    International Nuclear Information System (INIS)

    Widing, M. A.

    2002-01-01

    The Route and Landmark Selection Tool (RULST) is a software program designed to assist military planners in defining geographical objects, such as routes, landmarks, spurs, and yards, at a given facility. Argonne National Laboratory is currently developing a prototype of this tool for use by the Military Traffic Management Command Transportation Engineering Agency (MTMCTEA). The primary objective of RULST is to populate database tables of facility objects for use in MTMCTEA models. RULST defines facility data for use in models such as Port Simulation (PORTSIM) and Transportation System Capability (TRANSCAP), which simulate the transportation of equipment through ports and military installations. The main purpose of RULST is to allow you to specify the relationships between landmarks and routes. The nodes, links, and landmarks that describe a facility are often predefined on the basis of the layout of the physical site

  9. IDP STABILIZATION ASSISTANCE: ROUTES TO OPTIMIZATION IN UKRAINE

    Directory of Open Access Journals (Sweden)

    Yuliia Zavadovska

    2016-11-01

    Full Text Available The purpose of the paper is to advise to optimization improvement pathways in IDP stabilization system in Ukraine that currently lacks real-time global-scale coordination, resulting in less efficient peaceful change. It is argued that with funding uncertainty, the system halts at middle level, aiming at sustainability. The article states that to improve, it needs to maintain high motivation and marketability of its professionals through skills and professional certification. Future grassroots projects should focus on mind changes. Methodology. A desk and in-depth study has been carried out of several national IDP stabilization programs dealing with the government that ensure infrastructural support to communities hosting IDPs. It has been studied how the programs “mindchange” their stakeholders (2014-2016 data via regional NGOs and supports grassroots, using a real-time communication platform with features of cloud, internet banking, social network and dedicated server. Improving change generation tools, it leverages transformation with small, but not too small, resources to catalyze change. Results of the research showed that the bargain between external priorities and grassroots interests should favor program interest with “soft” projects, and listen to grassroots with “hard” projects. However, funding for non-state actors could have a 4–level structure, including: national projects for regional change strategies; regional NGO support funds; simple grassroots grants; and individual innovation prizes. Practical implications. Regional NGOs can improve beneficiary satisfaction and widen participation by supporting informal civic movements. For slowlyfunded programs, a pre-funding risk assessment report could be useful to assess change that is happening before the funding starts. Additionally, internships as a mind changing tool in IDP perception should focus on young professionals and high-ranked MPs, the latter to be engaged in group cooperation, aimed at professionalizing and strengthening their united voice to advance reforms in the region’s governments, the 60+ generation must give way to 50+ reformers and build on 35+ functional change-makers. Value/originality. The article concludes with the statement that we approach the need to establish an international coordination and control system, with IDPSA growing from an anti-poverty and democracy-building system – into the framework of support and stabilization the vital social functions in the regions of the world. While we agree that IDPSA in our region duplicates some functions of the state, therefore, it should be the state, supported by the global coordination system, which performs these functions directly – putting us closer to the developed economies and democracies of the world. According to the author, the structure of IDPSA might replace important sectorial functions in such states, building a humane world with common goals and aspirations of the higher values – where the combination of global security and humanism objectives and growth will be in harmony with the preservation of regional historical identity.

  10. 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.

  11. Principles of Vessel Route Planning in Ice on the Northern Sea Route

    Directory of Open Access Journals (Sweden)

    Tadeusz Pastusiak

    2016-12-01

    Full Text Available A complex of ice cover characteristics and the season of the year were considered in relation to vessel route planning in ice-covered areas on the NSR. The criteria for navigation in ice - both year-round and seasonal were analyzed. The analysis of the experts knowledge, dissipated in the literature, allowed to identify some rules of route planning in ice-covered areas. The most important processes from the navigation point of view are the development and disintegration of ice, the formation and disintegration of fast ice and behavior of the ice massifs and polynyas. The optimal route is selected on basis of available analysis and forecast maps of ice conditions and ice class, draught and seaworthiness of the vessel. The boundary of the ice indicates areas accessible to vessels without ice class. Areas with a concentration of ice from 0 to 6/10 are used for navigation of vessels of different ice classes. Areas of concentration of ice from 7/10 up are eligible for navigation for icebreakers and vessels with a high ice class with the assistance of icebreakers. These rules were collected in the decision tree. Following such developed decision-making model the master of the vessel may take decision independently by accepting grading criteria of priorities resulting from his knowledge, experience and the circumstances of navigation. Formalized form of decision making model reduces risk of the "human factor" in the decision and thereby help improve the safety of maritime transport.

  12. 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...

  13. Microwave-assisted rapid extracellular synthesis of stable bio-functionalized silver nanoparticles from guava (Psidium guajava) leaf extract

    Energy Technology Data Exchange (ETDEWEB)

    Raghunandan, Deshpande [H.K.E.S' s College of Pharmacy (India); Mahesh, Bedre D. [Gulbarga University, Materials Chemistry Laboratory, Department of Material Science (India); Basavaraja, S. [Jawaharlal Nehru Centre for Advanced Scientific Research, Veeco-India Nanotechnology Laboratory (India); Balaji, S. D. [Gulbarga University, Materials Chemistry Laboratory, Department of Material Science (India); Manjunath, S. Y. [Sri Krupa, Institute of Pharmaceutical Science (India); Venkataraman, A., E-mail: raman_chem@rediffmail.com [Gulbarga University, Materials Chemistry Laboratory, Department of Material Science (India)

    2011-05-15

    Our research interest centers on microwave-assisted rapid extracellular synthesis of bio-functionalized silver nanoparticles of 26 {+-} 5 nm from guava (Psidium guajava) leaf extract with control over dimension and composition. The reaction occurs very rapidly as the formation of spherical nanoparticles almost completed within 90 s. The probable pathway of the biosynthesis is suggested. Appearance, crystalline nature, size and shape of nanoparticles are understood by UV-vis (UV-vis spectroscopy), FTIR (fourier transform infrared spectroscopy), XRD (X-ray diffraction), FESEM (field emission scanning electron microscopy) and TEM (transmission electron microscopy) techniques. Microwave-assisted route is selected for the synthesis of silver nanoparticles to carry out the reaction fast, suppress the enzymatic action and to keep the process environmentally clean and green.

  14. Microwave-assisted rapid extracellular synthesis of stable bio-functionalized silver nanoparticles from guava (Psidium guajava) leaf extract

    International Nuclear Information System (INIS)

    Raghunandan, Deshpande; Mahesh, Bedre D.; Basavaraja, S.; Balaji, S. D.; Manjunath, S. Y.; Venkataraman, A.

    2011-01-01

    Our research interest centers on microwave-assisted rapid extracellular synthesis of bio-functionalized silver nanoparticles of 26 ± 5 nm from guava (Psidium guajava) leaf extract with control over dimension and composition. The reaction occurs very rapidly as the formation of spherical nanoparticles almost completed within 90 s. The probable pathway of the biosynthesis is suggested. Appearance, crystalline nature, size and shape of nanoparticles are understood by UV–vis (UV–vis spectroscopy), FTIR (fourier transform infrared spectroscopy), XRD (X-ray diffraction), FESEM (field emission scanning electron microscopy) and TEM (transmission electron microscopy) techniques. Microwave-assisted route is selected for the synthesis of silver nanoparticles to carry out the reaction fast, suppress the enzymatic action and to keep the process environmentally clean and green.

  15. Microwave-assisted rapid extracellular synthesis of stable bio-functionalized silver nanoparticles from guava ( Psidium guajava) leaf extract

    Science.gov (United States)

    Raghunandan, Deshpande; Mahesh, Bedre D.; Basavaraja, S.; Balaji, S. D.; Manjunath, S. Y.; Venkataraman, A.

    2011-05-01

    Our research interest centers on microwave-assisted rapid extracellular synthesis of bio-functionalized silver nanoparticles of 26 ± 5 nm from guava ( Psidium guajava) leaf extract with control over dimension and composition. The reaction occurs very rapidly as the formation of spherical nanoparticles almost completed within 90 s. The probable pathway of the biosynthesis is suggested. Appearance, crystalline nature, size and shape of nanoparticles are understood by UV-vis (UV-vis spectroscopy), FTIR (fourier transform infrared spectroscopy), XRD (X-ray diffraction), FESEM (field emission scanning electron microscopy) and TEM (transmission electron microscopy) techniques. Microwave-assisted route is selected for the synthesis of silver nanoparticles to carry out the reaction fast, suppress the enzymatic action and to keep the process environmentally clean and green.

  16. 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.

  17. Revealed Preference Methods for Studying Bicycle Route Choice—A Systematic Review

    Directory of Open Access Journals (Sweden)

    Ray Pritchard

    2018-03-01

    Full Text Available One fundamental aspect of promoting utilitarian bicycle use involves making modifications to the built environment to improve the safety, efficiency and enjoyability of cycling. Revealed preference data on bicycle route choice can assist greatly in understanding the actual behaviour of a highly heterogeneous group of users, which in turn assists the prioritisation of infrastructure or other built environment initiatives. This systematic review seeks to compare the relative strengths and weaknesses of the empirical approaches for evaluating whole journey route choices of bicyclists. Two electronic databases were systematically searched for a selection of keywords pertaining to bicycle and route choice. In total seven families of methods are identified: GPS devices, smartphone applications, crowdsourcing, participant-recalled routes, accompanied journeys, egocentric cameras and virtual reality. The study illustrates a trade-off in the quality of data obtainable and the average number of participants. Future additional methods could include dockless bikeshare, multiple camera solutions using computer vision and immersive bicycle simulator environments.

  18. 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,

  19. 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

  20. 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.

  1. 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

  2. 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…

  3. 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,…

  4. Sailing Vessel Routing Considering Safety Zone and Penalty Time for Altering Course

    Directory of Open Access Journals (Sweden)

    Marcin Zyczkowski

    2017-06-01

    Full Text Available In this paper we introduce new model for simulation sea vessel routing. Besides a vessel types (polar diagram and weather forecast, travel security and the number of maneuvers are considered. Based on these data both the minimal travelling costs and the minimal processing time are found for different vessels and different routes. To test our model the applications SailingAssistance wad improved. The obtained results shows that we can obtain quite acceptable results.

  5. Atmospheric Pressure Microwave Assisted Heterogeneous Catalytic Reactions

    Directory of Open Access Journals (Sweden)

    Ken Belmore

    2007-07-01

    Full Text Available The newly synthesized 5,10,15,20-tetra[3-(3-trifluoromethylphenoxy]porphyrin, TTFMPP, has been characterized using mass spectroscopy, 1H-, 13C- and 19F-NMR, MALDI-TOF mass spectrometry, UV-Vis and fluorescence spectrophotometry, andcyclic voltammetry. The NMR confirmed the structure of the compound and the massspectrum was in agreement with the proposed molecular formula. The UV-Vis absorptionspectrum of TTFMPP shows characteristic spectral patterns similar to those of tetraphenylporphryin, with a Soret band at 419 nm and four Q bands at 515, 550, 590, and 648 nm.Protonation of the porphyrin with TFA resulted in the expected red shift of the Soret band.Excitation at 419 nm gave an emission at 650 nm. The quantum yield of the porphyrin wasdetermined to be 0.08. Cyclic voltammetry was used to determine the oxidation andreduction potentials of the new porphyrin. Two quasi-reversible one-electron reductions at–1.00 and –1.32 V and a quasi-reversible oxidation at 1.20 V versus the silver/silverchloride reference electrode with tetrabutylammonium tetrafluoroborate as the supportingelectrolyte in methylene chloride were observed.

  6. A new combustion route to γ-Fe2O3 synthesis

    Indian Academy of Sciences (India)

    A new combustion route for the synthesis of -Fe2O3 is reported by employing purified -Fe2O3 as aprecursor in the present investigation. This synthesis which is similar to a self propagation combustion reaction, involves fewer steps, a shorter overall processing time, is a low energy reaction without the need of any ...

  7. Assistive Technology

    Science.gov (United States)

    ... Page Resize Text Printer Friendly Online Chat Assistive Technology Assistive technology (AT) is any service or tool that helps ... be difficult or impossible. For older adults, such technology may be a walker to improve mobility or ...

  8. Assisted Living

    Science.gov (United States)

    ... it, too. Back to top What is the Cost for Assisted Living? Although assisted living costs less than nursing home ... Primarily, older persons or their families pay the cost of assisted living. Some health and long-term care insurance policies ...

  9. 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

  10. 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 ...

  11. 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...

  12. 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

  13. Typing of Ochrobactrum anthropi clinical isolates using automated repetitive extragenic palindromic-polymerase chain reaction DNA fingerprinting and matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry.

    Science.gov (United States)

    Quirino, Angela; Pulcrano, Giovanna; Rametti, Linda; Puccio, Rossana; Marascio, Nadia; Catania, Maria Rosaria; Matera, Giovanni; Liberto, Maria Carla; Focà, Alfredo

    2014-03-22

    Ochrobactrum anthropi (O. anthropi), is a non-fermenting gram-negative bacillus usually found in the environment. Nevertheless, during the past decade it has been identified as pathogenic to immunocompromised patients. In this study, we assessed the usefulness of the automated repetitive extragenic palindromic-polymerase chain reaction (rep-PCR-based DiversiLab™ system, bioMèrieux, France) and of matrix-assisted laser desorption/ionization-time-of-flight (MALDI-TOF MS) for typing of twentythree O. anthropi clinical isolates that we found over a four-months period (from April 2011 to August 2011) in bacteriemic patients admitted in the same operative unit of our hospital. Pulsed-field gel electrophoresis (PFGE), commonly accepted as the gold standard technique for typing, was also used. Analysis was carried out using the Pearson correlation coefficient to determine the distance matrice and the unweighted pair group method with arithmetic mean (UPGMA) to generate dendogram. Rep-PCR analysis identified four different patterns: three that clustered together with 97% or more pattern similarity, and one whose members showed < 95% pattern similarity. Interestingly, strains isolated later (from 11/06/2011 to 24/08/2011) displayed a pattern with 99% similarity. MALDI-TOF MS evaluation clustered the twentythree strains of O. anthropi into a single group containing four distinct subgroups, each comprising the majority of strains clustering below 5 distance levels, indicating a high similarity between the isolates. Our results indicate that these isolates are clonally-related and the methods used afforded a valuable contribution to the epidemiology, prevention and control of the infections caused by this pathogen.

  14. 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....

  15. 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.

  16. 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.

  17. 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...

  18. 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

  19. 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...

  20. 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....

  1. 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...

  2. 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...

  3. Multi-Objective Weather Routing of Sailing Vessels

    Directory of Open Access Journals (Sweden)

    Życzkowski Marcin

    2017-12-01

    Full Text Available The paper presents a multi-objective deterministic method of weather routing for sailing vessels. Depending on a particular purpose of sailboat weather routing, the presented method makes it possible to customize the criteria and constraints so as to fit a particular user’s needs. Apart from a typical shortest time criterion, safety and comfort can also be taken into account. Additionally, the method supports dynamic weather data: in its present version short-term, mid-term and long-term term weather forecasts are used during optimization process. In the paper the multi-objective optimization problem is first defined and analysed. Following this, the proposed method solving this problem is described in detail. The method has been implemented as an online SailAssistance application. Some representative examples solutions are presented, emphasizing the effects of applying different criteria or different values of customized parameters.

  4. Summary of routes for different study of combustion reaction in scale pilot magnetic nanocatalysts production Ni{sub 0,5}Zn{sub 0,5}Fe{sub 2}O{sub 4}; Estudo de diferentes rotas da sintese por reacao de combustao em escala piloto para producao de nanocatalisadores magneticos Ni{sub 0,5}Zn{sub 0,5}Fe{sub 2}O{sub 4}

    Energy Technology Data Exchange (ETDEWEB)

    Barros, Ana Beatriz de Sousa; Moura, Thales Filipe Barbosa de; Vasconcelos, Erik Vilar; Pereira, Kleberson Ricardo de Oliveira; Dantas, Joelda; Costa, Ana Cristina Figueiredo de Melo, E-mail: ana_sousa_barros@hotmail.com [Universidade Federal de Campina Grande (UFCG), PB (Brazil)

    2016-07-01

    Biodiesel is derived from renewable sources and because of concerns about the environment, has gained relevance as regards the search for sustainable sources. It can be obtained by different processes consisting of a chemical reaction of vegetable oil or animal fat with a common alcohol, stimulated by a catalyst. In this work we used for the production of biodiesel the animal fat oil, beef tallow, because it’s a cheap raw material, avoiding discharges and pollution of the environment and considered to be a raw material clean. This study aimed to prepare a magnetic NiZn catalyst, wherein the synthesis was performed in two stainless steel containers with different capacity, PM and MM 10 and 30g / product by reacting, respectively, and characterized by XRD and EDX. The biodiesel was obtained by methyl esterification at 180 ° C / 1hrs, molar ratio 1:12, 2% catalys. Blank test was also conducted to compare the results. It was found that the two routes showed peaks of highest intensity corresponding to the cubic spinel crystalline phase majority of NiZn ferrite. The value of the crystallite size for the PM catalyst was higher by 23% compared to MM. The conversion into biodiesel results were approximately 62%, 42% and 5%, AM, and MM test blank respectively. So when comparing the blank test with PM and MM, the catalyst showed efficiency for the catalytic reaction, more effective for PM. (author)

  5. An Evolutionary Mobility Aware Multi-Objective Hybrid Routing Algorithm for Heterogeneous Wireless Sensor Networks

    DEFF Research Database (Denmark)

    Kulkarni, Nandkumar P.; Prasad, Neeli R.; Prasad, Ramjee

    deliberation. To tackle these two problems, Mobile Wireless Sensor Networks (MWSNs) is a better choice. In MWSN, Sensor nodes move freely to a target area without the need for any special infrastructure. Due to mobility, the routing process in MWSN has become more complicated as connections in the network can...... such as Average Energy consumption, Control Overhead, Reaction Time, LQI, and HOP Count. The authors study the influence of energy heterogeneity and mobility of sensor nodes on the performance of EMRP. The Performance of EMRP compared with Simple Hybrid Routing Protocol (SHRP) and Dynamic Multi-Objective Routing...

  6. 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.

  7. Nuclear reactions

    International Nuclear Information System (INIS)

    Lane, A.M.

    1980-01-01

    In reviewing work at Harwell over the past 25 years on nuclear reactions it is stated that a balance has to be struck in both experiment and theory between work on cross-sections of direct practical relevance to reactors and on those relevant to an overall understanding of reaction processes. The compound nucleus and direct process reactions are described. Having listed the contributions from AERE, Harwell to developments in nuclear reaction research in the period, work on the optical model, neutron capture theory, reactions at doorway states with fine structure, and sum-rules for spectroscopic factors are considered in more detail. (UK)

  8. 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.

  9. Synthesis of 3-Alkenyl-1-azaanthraquinones via Diels-Alder and Electron Transfer Reactions

    Directory of Open Access Journals (Sweden)

    Patrice Vanelle

    2002-12-01

    Full Text Available A convenient route to 3-alkenyl-1-azaanthraquinones via a hetero Diels-Alder reaction between an azadiene and naphthoquinone, a free radical chlorination and an electron transfer reaction is reported.

  10. assisted vaginal hysterectomy versus abdominal hysterectomy on ...

    African Journals Online (AJOL)

    minimal postoperative discomfort and less need for ... the feasibility of registrar training in laparoscopic-assisted vaginal hysterectomy (LAVH), and to investigate the impact of laparoscopy in changing the route of hysterectomy in women assessed as being unsuitable for ... All patients received prophylactic antibiotics during.

  11. Automation of route identification and optimisation based on data-mining and chemical intuition.

    Science.gov (United States)

    Lapkin, A A; Heer, P K; Jacob, P-M; Hutchby, M; Cunningham, W; Bull, S D; Davidson, M G

    2017-09-21

    Data-mining of Reaxys and network analysis of the combined literature and in-house reactions set were used to generate multiple possible reaction routes to convert a bio-waste feedstock, limonene, into a pharmaceutical API, paracetamol. The network analysis of data provides a rich knowledge-base for generation of the initial reaction screening and development programme. Based on the literature and the in-house data, an overall flowsheet for the conversion of limonene to paracetamol was proposed. Each individual reaction-separation step in the sequence was simulated as a combination of the continuous flow and batch steps. The linear model generation methodology allowed us to identify the reaction steps requiring further chemical optimisation. The generated model can be used for global optimisation and generation of environmental and other performance indicators, such as cost indicators. However, the identified further challenge is to automate model generation to evolve optimal multi-step chemical routes and optimal process configurations.

  12. Redox reactions in food fermentations

    DEFF Research Database (Denmark)

    Hansen, Egon Bech

    2018-01-01

    involves oxidative steps in the early part of the pathways whereas a multitude of different reactions are used as compensating reductions. Much of the diversity seen between food fermentations arise from the different routes and the different electron acceptors used by microorganisms to counterbalance...... and this contributes to the diversity in flavor, color, texture, and shelf life. The review concludes that these reactions are still only incompletely understood and that they represent an interesting area for fundamental research and also represent a fertile field for product development through a more conscious use...... of the redox properties of strains used to compose food cultures....

  13. 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.

  14. An Opportunistic Routing for Data Forwarding Based on Vehicle Mobility Association in Vehicular Ad Hoc Networks

    Directory of Open Access Journals (Sweden)

    Leilei Wang

    2017-11-01

    Full Text Available Vehicular ad hoc networks (VANETs have emerged as a new powerful technology for data transmission between vehicles. Efficient data transmission accompanied with low data delay plays an important role in selecting the ideal data forwarding path in VANETs. This paper proposes a new opportunity routing protocol for data forwarding based on vehicle mobility association (OVMA. With assistance from the vehicle mobility association, data can be forwarded without passing through many extra intermediate nodes. Besides, each vehicle carries the only replica information to record its associated vehicle information, so the routing decision can adapt to the vehicle densities. Simulation results show that the OVMA protocol can extend the network lifetime, improve the performance of data delivery ratio, and reduce the data delay and routing overhead when compared to the other well-known routing protocols.

  15. International assistance. Licensing assistance project

    International Nuclear Information System (INIS)

    Aleev, A.

    1999-01-01

    Description of licensing assistance project for VATESI is presented. In licensing of unit No.1 of INPP VATESI is supported by many western countries. Experts from regulatory bodies or scientific organizations of those countries assist VATESI staff in reviewing documentation presented by INPP. Among bilateral cooperation support is provided by European Commission through Phare programme

  16. Prospect theory based estimation of drivers' risk attitudes in route choice behaviors.

    Science.gov (United States)

    Zhou, Lizhen; Zhong, Shiquan; Ma, Shoufeng; Jia, Ning

    2014-12-01

    This paper applied prospect theory (PT) to describe drivers' route choice behavior under Variable Message Sign (VMS), which presented visual traffic information to assist them to make route choice decisions. A quite rich empirical data from questionnaire and field spot was used to estimate parameters of PT. In order to make the parameters more realistic with drivers' attitudes, they were classified into different types by significant factors influencing their behaviors. Based on the travel time distribution of alternative routes and route choice results from questionnaire, the parameterized value function of each category was figured out, which represented drivers' risk attitudes and choice characteristics. The empirical verification showed that the estimates were acceptable and effective. The result showed drivers' risk attitudes and route choice characteristics could be captured by PT under real-time information shown on VMS. For practical application, once drivers' route choice characteristics and parameters were identified, their route choice behavior under different road conditions could be predicted accurately, which was the basis of traffic guidance measures formulation and implementation for targeted traffic management. Moreover, the heterogeneous risk attitudes among drivers should be considered when releasing traffic information and regulating traffic flow. Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. Insights into the Diels-Alder Reaction between 3-Vinylindoles and Methyleneindolinone without and with the Assistance of Hydrogen-Bonding Catalyst Bisthiourea: Mechanism, Origin of Stereoselectivity, and Role of Catalyst.

    Science.gov (United States)

    Yan, Chao-Xian; Yang, Fan; Yang, Xing; Zhou, Da-Gang; Zhou, Pan-Pan

    2017-03-17

    The Diels-Alder reaction between 3-vinylindoles and methyleneindolinone can proceed both under catalyst-free conditions and with bisthiourea as the catalyst. The reaction with bisthiourea is much faster and results in higher stereoselectivity of the product. The reaction mechanism, origin of stereoselectivity, and role of the catalyst were elaborated based on quantum mechanical calculations and theoretical methods of reactivity indices, NCI, QTAIM, and distortion/interaction models. In the uncatalyzed reaction, the two C-C bonds that are formed undergo conversion from noncovalent to covalent bonding via a concerted asynchronous mechanism. The weak intermolecular interactions formed in the transition state play important roles. The difference between the interaction and distortion energies is responsible for the stereoselectivity. In the catalyzed reaction, bisthiourea induces both the diene and dienophile to approach it via weak intermolecular interactions, which greatly lowers the energy barrier of the reaction and leads to the product with excellent stereoselectivity. The possible pathways of this reaction were explored, which suggested that the formation of the two C-C bonds goes through either a stepwise or concerted asynchronous mechanism. These results detail the reaction mechanism and shed light on both the significant role of the bisthiourea catalyst and the origin of stereoselectivity for this type of Diels-Alder reaction and related ones.

  18. 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.

  19. 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.

  20. 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

  1. 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

  2. RECONFIGURABLE PRODUCT ROUTING AND CONTROL FOR MASS CUSTOMISATION MANUFACTURING

    Directory of Open Access Journals (Sweden)

    A. J. Walker

    2012-01-01

    Full Text Available

    ENGLISH ABSTRACT:Reconfigurable control of flexible manufacturing systems can allow for the efficient and responsive production of customised product instances. This can aid in providing make-to-order business models for various small- to medium-sized enterprises in South Africa, and provide competitive advantage in a dynamic global marketplace. Reconfigurable control application requires an understanding of the modes of production variability in mass customisation manufacturing. Temporally uncorrelated workflow routings are considered as one of these production variability modes. In this light, this paper addresses the flexible material payload routing problem, and presents a mobile robot platform that has been developed to research and design reconfigurable routing systems.

    AFRIKAANSE OPSOMMING:Verstelbare beheer van aanpasbare vervaardigingstelsels kan die doeltreffende en reaktiewe produksie van doelgemaakte produkeksemplare toelaat. Hierdie beheer kan assisteer in die voorsiening van vervaardig-na-bestellingbesigheidsmodelle aan ’n aantal klein- tot medium-grootte ondernemings in Suid-Afrika, en aan hulle ’n kompeterende voorsprong bied in ’n dinamiese globale mark. Die instelling van verstelbare beheer vereis dat die modi van produkveranderlikheid in massa verbruikersaanpassingsvervaardiging verstaan word. Hierdie artikel spreek die probleem van aanpasbare roetebepaling van materiaalvragte in massa verbruikersaanpassingsvervaardiging aan. ’n Mobiele robot-platform, ontwikkel vir navorsing in verstelbare roetebepalingstelsels, word ook voorgelê.

  3. 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

  4. 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...

  5. From Resource-Adaptive Navigation Assistance to Augmented Cognition

    Science.gov (United States)

    Zimmer, Hubert D.; Münzer, Stefan; Baus, Jörg

    In an assistance scenario, a computer provides purposive information supporting a human user in an everyday situation. Wayfinding with navigation assistance is a prototypical assistance scenario. The present chapter analyzes the interplay of the resources of the assistance system and the resources of the user. The navigation assistance system provides geographic knowledge, positioning information, route planning, spatial overview information, and route commands at decision points. The user's resources encompass spatial knowledge, spatial abilities and visuo-spatial working memory, orientation strategies, and cultural habit. Flexible adaptations of the assistance system to available resources of the user are described, taking different wayfinding goals, situational constraints, and individual differences into account. Throughout the chapter, the idea is pursued that the available resources of the user should be kept active.

  6. 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.

  7. 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...

  8. 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.

  9. 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

  10. 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...

  11. 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

  12. A Networks Approach to Modeling Enzymatic Reactions.

    Science.gov (United States)

    Imhof, P

    2016-01-01

    Modeling enzymatic reactions is a demanding task due to the complexity of the system, the many degrees of freedom involved and the complex, chemical, and conformational transitions associated with the reaction. Consequently, enzymatic reactions are not determined by precisely one reaction pathway. Hence, it is beneficial to obtain a comprehensive picture of possible reaction paths and competing mechanisms. By combining individually generated intermediate states and chemical transition steps a network of such pathways can be constructed. Transition networks are a discretized representation of a potential energy landscape consisting of a multitude of reaction pathways connecting the end states of the reaction. The graph structure of the network allows an easy identification of the energetically most favorable pathways as well as a number of alternative routes. © 2016 Elsevier Inc. All rights reserved.

  13. Aza-Michael reaction: achievements and prospects

    International Nuclear Information System (INIS)

    Rulev, Alexander Yu

    2011-01-01

    Data published in the last 10 years on the use of the aza-Michael reaction in organic synthesis are described systematically. The attention is focused on environmentally friendly processes following green chemistry principles and on methods for the synthesis of compounds that are difficult to access by other routes.

  14. Quasielastic reactions

    International Nuclear Information System (INIS)

    Henning, W.

    1979-01-01

    Quasielastic reaction studies, because of their capability to microscopically probe nuclear structure, are still of considerable interest in heavy-ion reactions. The recent progress in understanding various aspects of the reaction mechanism make this aim appear closer. The relation between microscopic and macroscopic behavior, as suggested, for example, by the single proton transfer data to individual final states or averaged excitation energy intervals, needs to be explored. It seems particularly useful to extend measurements to higher incident energies, to explore and understand nuclear structure aspects up to the limit of the energy range where they are important

  15. 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

  16. 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

  17. 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.

  18. 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

  19. 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...

  20. 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

  1. 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

  2. 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

  3. 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

  4. 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 ...

  5. 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

  6. 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...

  7. 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

  8. 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

  9. Microwave-assisted 'greener' synthesis of organics and nanomaterials

    Science.gov (United States)

    Microwave selective heating techniques in conjunction with greener reaction media are dramatically reducing chemical waste and reaction times in several organic transformations and material synthesis. This presentation summarizes author’s own experience in developing MW-assisted ...

  10. cycloaddition reactions

    Indian Academy of Sciences (India)

    Unknown

    Molecular Modeling Group, Organic Chemical Sciences, Indian Institute of Chemical Technology,. Hyderabad ... thus obtained are helpful to model the regioselectivity ... compromise to model Diels–Alder reactions involving ...... acceptance.

  11. 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.

  12. 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.

  13. 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.

  14. 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

  15. Design of a mesoscale continuous flow route towards lithiated methoxyallene.

    Science.gov (United States)

    Seghers, Sofie; Heugebaert, Thomas S A; Moens, Matthias; Sonck, Jolien; Thybaut, Joris; Stevens, Chris Victor

    2018-05-11

    The unique nucleophilic properties of lithiated methoxyallene allow for C-C bond formation with a wide variety of electrophiles, thus introducing an allenic group for further functionalization. This approach has yielded a tremendously broad range of (hetero)cyclic scaffolds, including API precursors. To date, however, its valorization at scale is hampered by the batch synthesis protocol which suffers from serious safety issues. Hence, the attractive heat and mass transfer properties of flow technology were exploited to establish a mesoscale continuous flow route towards lithiated methoxyallene. An excellent conversion of 94% was obtained, corresponding to a methoxyallene throughput of 8.2 g/h. The process is characterized by short reaction times, mild reaction conditions and a stoichiometric use of reagents. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. 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.

  17. 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.

  18. 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.

  19. 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.)

  20. Anionic PPV polymerization from the sulfinyl precursor route : Block copolymer formation from sequential addition of monomers

    NARCIS (Netherlands)

    Cosemans, Inge; Vandenbergh, Joke; Voet, Vincent S. D.; Loos, Katja; Lutsen, Laurence; Vanderzande, Dirk; Junkers, Thomas

    2013-01-01

    The sulfinyl precursor route for the synthesis of poly(p-phenylene vinylene) (PPV) materials via an anionic polymerization procedure employing dedicated initiators is evaluated in depth. Reaction kinetics are investigated to gain more control over the polymerization, since polymerization proceeds to

  1. 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

  2. Microwave-Assisted Synthesis of Phenothiazine and Quinoline Derivatives

    Science.gov (United States)

    Găină, Luiza; Cristea, Castelia; Moldovan, Claudia; Porumb, Dan; Surducan, Emanoil; Deleanu, Călin; Mahamoud, Abdalah; Barbe, Jacques; Silberg, Ioan A.

    2007-01-01

    Application of a dynamic microwave power system in the chemical synthesis of some phenothiazine and quinoline derivatives is described. Heterocyclic ring formation, aromatic nucleophilic substitution and heterocyclic aldehydes/ketones condensation reactions were performed on solid support, or under solvent free reaction conditions. The microwave-assisted Duff formylation of phenothiazine was achieved. Comparison of microwave-assisted synthesis with the conventional synthetic methods demonstrates advantages related to shorter reaction times and in some cases better reaction yields.

  3. A facile route to shape controlled CdTe nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Mntungwa, Nhlakanipho; Rajasekhar, Pullabhotla V.S.R. [Department of Chemistry, University of Zululand, Private Bag X1001, KwaDlangezwa 3886, Empangeni, KZN (South Africa); Revaprasadu, Neerish, E-mail: nrevapra@pan.uzulu.ac.za [Department of Chemistry, University of Zululand, Private Bag X1001, KwaDlangezwa 3886, Empangeni, KZN (South Africa)

    2011-04-15

    Research highlights: {yields} A facile hybrid solution based/thermolysis route has been used for the synthesis of hexadecylamine capped CdTe nanoparticles. {yields} This method involves the reaction by the addition of an aqueous suspension of a cadmium salt to a freshly prepared NaHTe solution. {yields} The cadmium salt plays an important role in the growth mechanism of the particles and hence its final morphology. - Abstract: Hexadecylamine (HDA) capped CdTe nanoparticles have been synthesized using a facile hybrid solution based/thermolysis route. This method involves the reaction by the addition of an aqueous suspension or solution of a cadmium salt (chloride, acetate, nitrate or carbonate) to a freshly prepared NaHTe solution. The isolated CdTe was then dispersed in tri-octylphosphine (TOP) and injected into pre-heated HDA at temperatures of 190, 230 and 270 deg. C for 2 h. The particle growth and size distribution of the CdTe particles synthesized using cadmium chloride as the cadmium source were monitored using absorption and photoluminescence spectroscopy. The final morphology of the CdTe nanoparticles synthesized from the various cadmium sources was studied by transmission electron microscopy (TEM) and high resolution TEM. The cadmium source has an influence on the final morphology of the particles.

  4. A facile route to shape controlled CdTe nanoparticles

    International Nuclear Information System (INIS)

    Mntungwa, Nhlakanipho; Rajasekhar, Pullabhotla V.S.R.; Revaprasadu, Neerish

    2011-01-01

    Research highlights: → A facile hybrid solution based/thermolysis route has been used for the synthesis of hexadecylamine capped CdTe nanoparticles. → This method involves the reaction by the addition of an aqueous suspension of a cadmium salt to a freshly prepared NaHTe solution. → The cadmium salt plays an important role in the growth mechanism of the particles and hence its final morphology. - Abstract: Hexadecylamine (HDA) capped CdTe nanoparticles have been synthesized using a facile hybrid solution based/thermolysis route. This method involves the reaction by the addition of an aqueous suspension or solution of a cadmium salt (chloride, acetate, nitrate or carbonate) to a freshly prepared NaHTe solution. The isolated CdTe was then dispersed in tri-octylphosphine (TOP) and injected into pre-heated HDA at temperatures of 190, 230 and 270 deg. C for 2 h. The particle growth and size distribution of the CdTe particles synthesized using cadmium chloride as the cadmium source were monitored using absorption and photoluminescence spectroscopy. The final morphology of the CdTe nanoparticles synthesized from the various cadmium sources was studied by transmission electron microscopy (TEM) and high resolution TEM. The cadmium source has an influence on the final morphology of the particles.

  5. Assisted Living

    Science.gov (United States)

    ... a resident's needs depends as much on the philosophy and services of the assisted living facility as it does on the quality of care. The Administration on Aging, a part of the U.S. Department of Health and Human Services (HHS), offers these suggestions to help you ...

  6. Assistive Devices

    Science.gov (United States)

    If you have a disability or injury, you may use a number of assistive devices. These are tools, products or types of equipment that help you perform tasks and activities. They may help you move around, see, communicate, eat, or get ...

  7. Direct Reactions

    Energy Technology Data Exchange (ETDEWEB)

    Austern, N. [University of Pittsburgh, Pittsburgh, PA (United States)

    1963-01-15

    In order to give a unified presentation of one point of view, these lectures are devoted only to a detailed development of the standard theories of direct reactions, starting from basic principles. Discussion is given of the present status of the theories, of the techniques used for practical calculation, and of possible future developments. The direct interaction (DI) aspects of a reaction are those which involve only a few of the many degrees of freedom of a nucleus. In fact the minimum number of degrees of freedom which must be involved in a reaction are those required to describe the initial and final channels, and DI studies typically consider these degrees of freedom and no others. Because of this simplicity DI theories may be worked out in painstaking detail. DI processes concern only part of the wave function for a problem. The other part involves complicated excitations of many degrees of freedom, and gives the compound nucleus (CN) effects. While it is extremely interesting to learn how to separate DI and CN effects in an orderly manner, if they are both present in a reaction, no suitable method has yet been found. Instead, current work stresses the kinds of reactions and the kinds of final states in which DI effects dominate and in which CN effects may almost be forgotten. The DI cross-sections which are studied are often extremely large, comparable to elastic scattering cross-sections. (author)

  8. Efficient Synthesis of Spirobarbiturates and Spirothiobarbiturates Bearing Cyclopropane Rings by Rhodium(II)-Catalyzed Reactions of Cyclic Diazo Compounds

    International Nuclear Information System (INIS)

    Wang, Xue; Lee, Yong Rok

    2013-01-01

    Rhodium(II)-catalyzed reactions of cyclic diazo compounds derived from barbituric acid and thiobarbituric acid with a variety of styrene moieties were examined. These reactions provide rapid synthetic routes to the preparations of spirobarbiturates and spirothiobarbiturates bearing cyclopropane rings

  9. Efficient Synthesis of Spirobarbiturates and Spirothiobarbiturates Bearing Cyclopropane Rings by Rhodium(II)-Catalyzed Reactions of Cyclic Diazo Compounds

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Xue; Lee, Yong Rok [Yeungnam Univ., Gyeongsan (Korea, Republic of)

    2013-06-15

    Rhodium(II)-catalyzed reactions of cyclic diazo compounds derived from barbituric acid and thiobarbituric acid with a variety of styrene moieties were examined. These reactions provide rapid synthetic routes to the preparations of spirobarbiturates and spirothiobarbiturates bearing cyclopropane rings.

  10. 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.

  11. 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)

  12. Kinetic modelling of reactions in heated disaccharide-casein systems

    NARCIS (Netherlands)

    Brands, C.M.J.; Boekel, van M.A.J.S.

    2003-01-01

    The reactions occurring in disaccharide-casein reaction mixtures during heating at 120 degreesC and pH 6.8 were studied. The existence of two main degradation routes were established: (1) Isomerisation of the aldose sugars lactose and maltose in their ketose isomers lactulose and maltulose,

  13. Uranium oxide nanocrystals by microwave-assisted thermal decomposition. Electronic and structural properties

    International Nuclear Information System (INIS)

    Leduc, Jennifer; Mathur, Sanjay; Pacold, Joseph I.; Shuh, David K.; Dong, Chung-Li

    2018-01-01

    Uranium oxides have attracted much attention not only in the context of nuclear energy generation but also for their application as pristine catalysts or as supports for other (transition metal) oxides and (precious) metals. Their propensity to adopt high coordination numbers and manifest multiple oxidation states (from +II to +VI) makes them attractive candidates for catalyzed transformation reactions. Herein, we report a new synthesis route to phase-pure, crystalline UO 2 nanoparticles via microwave-assisted decomposition of a molecular uranium(IV) precursor. The electronic structure and optical absorption properties of these nanocrystals were investigated using spectroscopic methods to evaluate their suitability for photo(electro)catalytic applications. (copyright 2018 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  14. Uranium oxide nanocrystals by microwave-assisted thermal decomposition. Electronic and structural properties

    Energy Technology Data Exchange (ETDEWEB)

    Leduc, Jennifer; Mathur, Sanjay [Institute of Inorganic Chemistry, University of Cologne (Germany); Pacold, Joseph I.; Shuh, David K. [Chemical Sciences Division, The Glenn T. Seaborg Center, Lawrence Berkeley National Laboratory, Berkeley, CA (United States); Dong, Chung-Li [Department of Physics, Tamkang University, Tamsui, Taiwan (China)

    2018-01-17

    Uranium oxides have attracted much attention not only in the context of nuclear energy generation but also for their application as pristine catalysts or as supports for other (transition metal) oxides and (precious) metals. Their propensity to adopt high coordination numbers and manifest multiple oxidation states (from +II to +VI) makes them attractive candidates for catalyzed transformation reactions. Herein, we report a new synthesis route to phase-pure, crystalline UO{sub 2} nanoparticles via microwave-assisted decomposition of a molecular uranium(IV) precursor. The electronic structure and optical absorption properties of these nanocrystals were investigated using spectroscopic methods to evaluate their suitability for photo(electro)catalytic applications. (copyright 2018 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  15. 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...

  16. Reaction mechanisms

    International Nuclear Information System (INIS)

    Nguyen Trong Anh

    1988-01-01

    The 1988 progress report of the Reaction Mechanisms laboratory (Polytechnic School, France), is presented. The research topics are: the valence bond methods, the radical chemistry, the modelling of the transition states by applying geometric constraints, the long range interactions (ion - molecule) in gaseous phase, the reaction sites in gaseous phase and the mass spectroscopy applications. The points of convergence between the investigations of the mass spectroscopy and the theoretical chemistry teams, as well as the purposes guiding the research programs, are discussed. The published papers, the conferences, the congress communications and the thesis, are also reported [fr

  17. 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 ...

  18. Foreign assistance

    International Nuclear Information System (INIS)

    1991-07-01

    This paper reports that providing energy assistance to developing countries remains a relatively low priority of the Agency for International Development. AID is helping some developing countries meet their energy needs, but this assistance varies substantially because of the agency's decentralized structure. Most AID energy funding has gone to a handful of countries-primarily Egypt and Pakistan. With limited funding in most other countries, AID concentrates on providing technical expertise and promoting energy policy reforms that will encourage both energy efficiency and leverage investment by the private sector and other donors. Although a 1989 congressional directive to pursue a global warming initiative has had a marginal impact on the agency's energy programming, many AID energy programs, including those directed at energy conservation, help address global warming concerns

  19. Allergic reactions

    Science.gov (United States)

    ... that don't bother most people (such as venom from bee stings and certain foods, medicines, and pollens) can ... person. If the allergic reaction is from a bee sting, scrape the ... more venom. If the person has emergency allergy medicine on ...

  20. 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...

  1. 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 ...

  2. 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...

  3. 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....

  4. 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.

  5. 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...

  6. 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...

  7. 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...

  8. 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...

  9. Thermogravimetric analysis and kinetic study of formation of lithium titanate by solid state route

    International Nuclear Information System (INIS)

    Sonak, Sagar; Jain, Uttam; Sahu, Ashok Kumar; Kumar, Sanjay; Krishnamurthy, Nagaiyar

    2015-01-01

    The kinetics of formation of lithium titanate from the solid state reaction of lithium carbonate and titanium oxide was studied using non-isothermal thermogravimetric technique. Thermogravimetric data for the reaction of lithium carbonate and titanium oxide was obtained at various heating rates. The methods such as Flynn–Wall–Ozawa and Kissinger–Akahira–Sunose were used to estimate the kinetic parameters from the obtained thermogravimetric data. The average activation energy for the formation of lithium titanate by solid state route was found to be 243 kJ/mol K. The reaction mechanism was determined by the method given by Malek. It was found that the three dimensional diffusion model best describes the reaction kinetics. A kinetic equation describing the reaction is proposed and reaction mechanism is discussed

  10. 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

  11. 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...

  12. 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...

  13. 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...

  14. New degradation compounds from lignocellulosic biomass pretreatment: routes for formation of potent oligophenolic enzyme inhibitors

    DEFF Research Database (Denmark)

    Rasmussen, H.; Tanner, David Ackland; Sørensen, H. R.

    2017-01-01

    -condensation reactions involving aldol condensations, 1,4 additions to α,β unsaturated carbonyl compounds, 3-keto acid decarboxylations and oxidations. Furthermore, pentose reactions with phenolic lignin components are suggested. The identification of the central role of xylose in the reaction routes for oligophenolic...... inhibitor formation led to the solution to protect the reactive anomeric center in xylose. It is shown that protection of the anomeric center in in situ generated xylose with ethylene glycol monobutyl ether, during pretreatment of wheat straw, reduces the level of oligophenols by 73%. The results pave...

  15. 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

  16. 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.

  17. 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.

  18. 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...

  19. 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

  20. LOTIR: A Routing Protocol for Multi-hop V-to-I Communication Using Local Traffic Information

    Directory of Open Access Journals (Sweden)

    Kun-chan Lan

    2012-08-01

    Full Text Available Vehicular Ad Hoc Network (VANET is an emerging technology that can be applied to safety, transport efficiency, or infotainment applications for roads and highways. However, due to its unique features, such as dynamic mobility patterns and uneven distributions of vehicles, VANET faces many challenging research issues for robust data dissemination in the network. Many routing protocols have been proposed for VANET in the past few years, and the idea of utilizing a navigation system to assist the routing protocol for selecting the next best forwarder has become increasingly popular. However, it might not be realistic to assume that every vehicle is equipped with a navigation system. In addition, due to privacy concerns, drivers might not want to reveal their planned routes to other cars. In this work, we propose a new routing protocol, called LOTIR (LOcal Traffic Information Routing, that relies on only local traffic information and does not require the assistance of a navigation system. LOTIR is a DTN-based routing protocol that utilizes the car-following theory and traffic light information to decide the next carrier to forward the data to. We implement LOTIR in NS-2, and our results show that it can achieve similar performance as prior work which depends on the availability of global network topology information.

  1. 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.

  2. Multi-Sensor Information Fusion for Optimizing Electric Bicycle Routes Using a Swarm Intelligence Algorithm

    Science.gov (United States)

    Villarubia, Gabriel; De Paz, Juan F.; Bajo, Javier

    2017-01-01

    The use of electric bikes (e-bikes) has grown in popularity, especially in large cities where overcrowding and traffic congestion are common. This paper proposes an intelligent engine management system for e-bikes which uses the information collected from sensors to optimize battery energy and time. The intelligent engine management system consists of a built-in network of sensors in the e-bike, which is used for multi-sensor data fusion; the collected data is analysed and fused and on the basis of this information the system can provide the user with optimal and personalized assistance. The user is given recommendations related to battery consumption, sensors, and other parameters associated with the route travelled, such as duration, speed, or variation in altitude. To provide a user with these recommendations, artificial neural networks are used to estimate speed and consumption for each of the segments of a route. These estimates are incorporated into evolutionary algorithms in order to make the optimizations. A comparative analysis of the results obtained has been conducted for when routes were travelled with and without the optimization system. From the experiments, it is evident that the use of an engine management system results in significant energy and time savings. Moreover, user satisfaction increases as the level of assistance adapts to user behavior and the characteristics of the route. PMID:29088087

  3. Multi-Sensor Information Fusion for Optimizing Electric Bicycle Routes Using a Swarm Intelligence Algorithm

    Directory of Open Access Journals (Sweden)

    Daniel H. De La Iglesia

    2017-10-01

    Full Text Available The use of electric bikes (e-bikes has grown in popularity, especially in large cities where overcrowding and traffic congestion are common. This paper proposes an intelligent engine management system for e-bikes which uses the information collected from sensors to optimize battery energy and time. The intelligent engine management system consists of a built-in network of sensors in the e-bike, which is used for multi-sensor data fusion; the collected data is analysed and fused and on the basis of this information the system can provide the user with optimal and personalized assistance. The user is given recommendations related to battery consumption, sensors, and other parameters associated with the route travelled, such as duration, speed, or variation in altitude. To provide a user with these recommendations, artificial neural networks are used to estimate speed and consumption for each of the segments of a route. These estimates are incorporated into evolutionary algorithms in order to make the optimizations. A comparative analysis of the results obtained has been conducted for when routes were travelled with and without the optimization system. From the experiments, it is evident that the use of an engine management system results in significant energy and time savings. Moreover, user satisfaction increases as the level of assistance adapts to user behavior and the characteristics of the route.

  4. Multi-Sensor Information Fusion for Optimizing Electric Bicycle Routes Using a Swarm Intelligence Algorithm.

    Science.gov (United States)

    De La Iglesia, Daniel H; Villarrubia, Gabriel; De Paz, Juan F; Bajo, Javier

    2017-10-31

    The use of electric bikes (e-bikes) has grown in popularity, especially in large cities where overcrowding and traffic congestion are common. This paper proposes an intelligent engine management system for e-bikes which uses the information collected from sensors to optimize battery energy and time. The intelligent engine management system consists of a built-in network of sensors in the e-bike, which is used for multi-sensor data fusion; the collected data is analysed and fused and on the basis of this information the system can provide the user with optimal and personalized assistance. The user is given recommendations related to battery consumption, sensors, and other parameters associated with the route travelled, such as duration, speed, or variation in altitude. To provide a user with these recommendations, artificial neural networks are used to estimate speed and consumption for each of the segments of a route. These estimates are incorporated into evolutionary algorithms in order to make the optimizations. A comparative analysis of the results obtained has been conducted for when routes were travelled with and without the optimization system. From the experiments, it is evident that the use of an engine management system results in significant energy and time savings. Moreover, user satisfaction increases as the level of assistance adapts to user behavior and the characteristics of the route.

  5. A Route Guidance System for Car Finding in Indoor Parking Garages

    OpenAIRE

    Pei-Chun Lee; Sheng-Shih Wang

    2016-01-01

    This paper presents a route guidance system for car owners to find their cars in parking garages. The presents system comprises a positioning-assisting subsystem and a car-finding mobile app. The positioning-assisting subsystem mainly uses the iBeacon technology for indoor positioning. The car-finding mobile app guides car owners to their cars based on a non-map navigation strategy. This study also designs a virtual coordinate system to support identifying the locations of parking spaces and ...

  6. A simple route to synthesize multiform structures of tin oxide nanobelts and optical properties investigation

    International Nuclear Information System (INIS)

    Cheng Chuanwei; Xu Guoyue; Zhang Haiqian; Li Yingying; Luo Yan; Zhang Peigen

    2008-01-01

    Multiform structures of SnO 2 nanobelts including of zigzag, branching and straight structures have been synthesized by a simple molten-salt assisted route. The obtained samples were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM) and high resolution transmission electron microscope (HRTEM). The growth mechanism of zigzag nanobelts was proposed. A strong blue emission band centered in 425 nm was observed in the photoluminescence spectrum

  7. ADVERSE REACTIONS TO VACCINES AND WAYS OF ITS PREVENTION

    Directory of Open Access Journals (Sweden)

    Yelyseyeva I. V

    2011-04-01

    Full Text Available The overview concerns allergic reaction on vaccines and possible ways of increasing safety of immunization on basis of use of local specific immunotherapies (SIT experience, particularly the sublingual route. The use of chemically altered allergens, allergoids; alternative routes of administration, particularly the sublingual route; use of novel adjuvants, such as CpG oligonucleotides and mycobacterial vaccines; other approaches, such as allergenic peptides, relevant T-cell epitope peptide immunotherapy; DNA vaccination, recombinant and engineered allergens, chimeric molecules and combined therapy are all approaches that have yielded positive results to increase safety of SIT and improve its efficacy.

  8. WEAMR — A Weighted Energy Aware Multipath Reliable Routing Mechanism for Hotline-Based WSNs

    Directory of Open Access Journals (Sweden)

    Ki-Hyung Kim

    2013-05-01

    Full Text Available Reliable source to sink communication is the most important factor for an efficient routing protocol especially in domains of military, healthcare and disaster recovery applications. We present weighted energy aware multipath reliable routing (WEAMR, a novel energy aware multipath routing protocol which utilizes hotline-assisted routing to meet such requirements for mission critical applications. The protocol reduces the number of average hops from source to destination and provides unmatched reliability as compared to well known reactive ad hoc protocols i.e., AODV and AOMDV. Our protocol makes efficient use of network paths based on weighted cost calculation and intelligently selects the best possible paths for data transmissions. The path cost calculation considers end to end number of hops, latency and minimum energy node value in the path. In case of path failure path recalculation is done efficiently with minimum latency and control packets overhead. Our evaluation shows that our proposal provides better end-to-end delivery with less routing overhead and higher packet delivery success ratio compared to AODV and AOMDV. The use of multipath also increases overall life time of WSN network using optimum energy available paths between sender and receiver in WDNs.

  9. Reaction time for trimolecular reactions in compartment-based reaction-diffusion models

    Science.gov (United States)

    Li, Fei; Chen, Minghan; Erban, Radek; Cao, Yang

    2018-05-01

    Trimolecular reaction models are investigated in the compartment-based (lattice-based) framework for stochastic reaction-diffusion modeling. The formulae for the first collision time and the mean reaction time are derived for the case where three molecules are present in the solution under periodic boundary conditions. For the case of reflecting boundary conditions, similar formulae are obtained using a computer-assisted approach. The accuracy of these formulae is further verified through comparison with numerical results. The presented derivation is based on the first passage time analysis of Montroll [J. Math. Phys. 10, 753 (1969)]. Montroll's results for two-dimensional lattice-based random walks are adapted and applied to compartment-based models of trimolecular reactions, which are studied in one-dimensional or pseudo one-dimensional domains.

  10. An Examination of Visitors’ Interest in Tourist Cards and Cultural Routes in the Case of a Romanian Destination

    Directory of Open Access Journals (Sweden)

    Ana ISPAS

    2015-10-01

    Full Text Available Although tourist cards and cultural routes have been interesting innovations when they were launched on the international tourism market, they are rarely implemented in Romanian tourism destinations, especially in an integrated manner. This paper presents a theoretical model regarding the integration of tourist cards in cultural routes, based on the assumption that tourists who are interested in both products have similar demographic and travel characteristics. The research results outline only the infl uence of tourists’ travel characteristics on their interest to buy cultural routes and tourist cards. Leisure travelers should be the main targeted segment, as their probability to buy such products is higher than in the case of business or VFR (visit friends and relatives tourists. These results can assist the Destination Management Organizations (DMOs regarding the choice of marketing strategies aimed at integrating cultural routes in a tourist card.

  11. 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

  12. 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)

  13. 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.

  14. 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...

  15. 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.

  16. 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.

  17. Quasielastic reactions

    International Nuclear Information System (INIS)

    Hansen, O.

    1983-01-01

    A brief review is presented of the experimental and theoretical situation regarding transfer reactions and inelastic scattering. In the first category there is little (very little) precision data for heavy projectiles and consequently almost no experience with quantitative theoretical analysis. For the inelastic scattering the rather extensive data strongly supports the coupled channels models with collective formfactors. At the most back angles, at intensities about 10 -5 of Rutherford scattering, a second, compound-like mechanism becomes dominant. The description of the interplay of these two opposite mechanisms provides a new challenge for our understanding

  18. 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.

  19. 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.

  20. 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

  1. 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)

  2. 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)

  3. Microwave-Assisted Synthesis of Phenothiazine and Qinoline Derivatives

    Directory of Open Access Journals (Sweden)

    Ioan A. Silberg

    2007-02-01

    Full Text Available Application of a dynamic microwave power system in the chemical synthesis ofsome phenothiazine and quinoline derivatives is described. Heterocyclic ring formation,aromatic nucleophilic substitution and heterocyclic aldehydes/ketones condensationreactions were performed on solid support, or under solvent free reaction conditions. Themicrowave-assisted Duff formylation of phenothiazine was achieved. Comparison ofmicrowave-assisted synthesis with the conventional synthetic methods demonstratesadvantages related to shorter reaction times and in some cases better reaction yields.

  4. 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)

  5. 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

  6. Nuclear reactions

    International Nuclear Information System (INIS)

    Corner, J.; Richardson, K.; Fenton, N.

    1990-01-01

    Nuclear reactions' marks a new development in the study of television as an agency of public policy debate. During the Eighties, nuclear energy became a major international issue. The disasters at Three-mile Island and Chernobyl created a global anxiety about its risks and a new sensitivity to it among politicians and journalists. This book is a case-study into documentary depictions of nuclear energy in television and video programmes and into the interpretations and responses of viewers drawn from many different occupational groupings. How are the complex and specialist arguments about benefit, risk and proof conveyed through the different conventions of commentary, interview and film sequence? What symbolic associations does the visual language of television bring to portrayals of the issue? And how do viewers make sense of various and conflicting accounts, connecting what they see and hear on the screen with their pre-existing knowledge, experience and 'civic' expectations. The authors examine some of the contrasting forms and themes which have been used by programme makers to explain and persuade, and then give a sustained analysis of the nature and sources of viewers' own accounts. 'Nuclear Reactions' inquires into the public meanings surrounding energy and the environment, spelling out in its conclusion some of the implications for future media treatments of this issue. It is also a key contribution to the international literature on 'television knowledge' and the processes of active viewing. (author)

  7. 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.

  8. Evolution Strategies in the Multipoint Connections Routing

    Directory of Open Access Journals (Sweden)

    L. Krulikovska

    2010-09-01

    Full Text Available Routing of multipoint connections plays an important role in final cost and quality of a found connection. New algorithms with better results are still searched. In this paper, a possibility of using the evolution strategies (ES for routing is presented. Quality of found connection is evaluated from the view of final cost and time spent on a searching procedure. First, parametrical analysis of results of the ES are discussed and compared with the Prim’s algorithm, which was chosen as a representative of the deterministic routing algorithms. Second, ways for improving the ES are suggested and implemented. The obtained results are reviewed. The main improvements are specified and discussed in conclusion.

  9. Hazardous materials routing - risk management of mismanagement

    International Nuclear Information System (INIS)

    Glickman, T.S.

    1988-01-01

    Along with emergency planning and preparedness, the placement of restrictions on routing has become an increasingly popular device for managing the highway and rail risks of hazardous materials transportation. Federal studies conducted in 1985 indicate that at that time there were 513 different state and local restrictions on the routing of hazardous materials for these two modes of transportation, and that there were 136 state and local notification requirements, that is, restrictions that take the form of a statute or ordinance requiring advance warning or periodic reporting about hazardous materials shipments. Routing restrictions also take the form of prohibiting the use of road, a tunnel, or a bridge for a specified set of hazardous materials

  10. Generalized routing protocols for multihop relay networks

    KAUST Repository

    Khan, Fahd Ahmed

    2011-07-01

    Performance of multihop cooperative networks depends on the routing protocols employed. In this paper we propose the last-n-hop selection protocol, the dual path protocol, the forward-backward last-n-hop selection protocol and the forward-backward dual path protocol for the routing of data through multihop relay networks. The average symbol error probability performance of the schemes is analysed by simulations. It is shown that close to optimal performance can be achieved by using the last-n-hop selection protocol and its forward-backward variant. Furthermore we also compute the complexity of the protocols in terms of number of channel state information required and the number of comparisons required for routing the signal through the network. © 2011 IEEE.

  11. Next Generation Network Routing and Control Plane

    DEFF Research Database (Denmark)

    Fu, Rong

    proved, the dominating Border Gateway Protocol (BGP) cannot address all the issues that in inter-domain QoS routing. Thus a new protocol or network architecture has to be developed to be able to carry the inter-domain traffic with the QoS and TE consideration. Moreover, the current network control also...... lacks the ability to cooperate between different domains and operators. The emergence of label switching transport technology such as of Multi-Protocol Label Switching (MPLS) or Generalized MPLS (GMPLS) supports the traffic transport in a finer granularity and more dedicated end-to-end Quality...... (RACF) provides the platform that enables cooperation and ubiquitous integration between networks. In this paper, we investigate in the network architecture, protocols and algorithms for inter-domain QoS routing and traffic engineering. The PCE based inter-domain routing architecture is enhanced...

  12. Waste Collection Vehicle Routing Problem: Literature Review

    Directory of Open Access Journals (Sweden)

    Hui Han

    2015-08-01

    Full Text Available Waste generation is an issue which has caused wide public concern in modern societies, not only for the quantitative rise of the amount of waste generated, but also for the increasing complexity of some products and components. Waste collection is a highly relevant activity in the reverse logistics system and how to collect waste in an efficient way is an area that needs to be improved. This paper analyzes the major contribution about Waste Collection Vehicle Routing Problem (WCVRP in literature. Based on a classification of waste collection (residential, commercial and industrial, firstly the key findings for these three types of waste collection are presented. Therefore, according to the model (Node Routing Problems and Arc Routing problems used to represent WCVRP, different methods and techniques are analyzed in this paper to solve WCVRP. This paper attempts to serve as a roadmap of research literature produced in the field of WCVRP.

  13. The Porphobilinogen Conundrum in Prebiotic Routes to Tetrapyrrole Macrocycles

    Science.gov (United States)

    Taniguchi, Masahiko; Ptaszek, Marcin; Chandrashaker, Vanampally; Lindsey, Jonathan S.

    2017-03-01

    Attempts to develop a credible prebiotic route to tetrapyrroles have relied on enzyme-free recapitulation of the extant biosynthesis, but this process has foundered from the inability to form the pyrrole porphobilinogen ( PBG) in good yield by self-condensation of the precursor δ-aminolevulinic acid ( ALA). PBG undergoes robust oligomerization in aqueous solution to give uroporphyrinogen (4 isomers) in good yield. ALA, PBG, and uroporphyrinogen III are universal precursors to all known tetrapyrrole macrocycles. The enzymic formation of PBG entails carbon-carbon bond formation between the less stable enolate/enamine of one ALA molecule (3-position) and the carbonyl/imine (4-position) of the second ALA molecule; without enzymes, the first ALA reacts at the more stable enolate/enamine (5-position) and gives the pyrrole pseudo-PBG. pseudo-PBG cannot self-condense, yet has one open α-pyrrole position and is proposed to be a terminator of oligopyrromethane chain-growth from PBG. Here, 23 analogues of ALA have been subjected to density functional theoretical (DFT) calculations, but no motif has been identified that directs reaction at the 3-position. Deuteriation experiments suggested 5-(phosphonooxy)levulinic acid would react preferentially at the 3- versus 5-position, but a hybrid condensation with ALA gave no observable uroporphyrin. The results suggest efforts toward a biomimetic, enzyme-free route to tetrapyrroles from ALA should turn away from structure-directed reactions and focus on catalysts that orient the two aminoketones to form PBG in a kinetically controlled process, thereby avoiding formation of pseudo-PBG.

  14. Eco-sustainable routing in optical networks

    DEFF Research Database (Denmark)

    Ricciardi, Sergio; Wang, Jiayuan; Palmieri, Francesco

    2013-01-01

    infrastructures are now widely recognized to play a fundamental role in the emission of green-house gases (GHG) in the at- mosphere, signicantly aecting the environmental sustainability of new evolutions in network architectures as well as technological developments in communication devices. In this paper......, a novel eco-sustainable Routing and Wavelength Assignment (RWA) algorithm, based on shortest-path routing with an adaptive link weighting function relying on an extension of the OSPF-TE protocol to convey carbon footprint information, has been proposed to decrease the network ecological impact while...

  15. Applied Multiprotocol Routing in IP Telephony

    Directory of Open Access Journals (Sweden)

    Miroslav Voznak

    2010-01-01

    Full Text Available The aim of the project was to create a multi-protocol system using SIP, H.323 and MGCP standards, which would ensure routing to various types of VoIP networks. The priority was to provide multi-protocol support to SIP and H.323 signalling and the support of the routing using the ENUM standard which has recently passed from the trial phase into full operation in the Czech Republic. The document describes the system's architecture and the components used. It also briefly describes ENUM.

  16. PROPOSAL OF ALGORITHM FOR ROUTE OPTIMIZATION

    Directory of Open Access Journals (Sweden)

    Robert Ramon de Carvalho Sousa

    2016-06-01

    Full Text Available This article uses “Six Sigma” methodology for the elaboration of an algorithm for routing problems which is able to obtain more efficient results than those from Clarke and Wright´s (CW algorithm (1964 in situations of random increase of product delivery demands, facing the incapability of service level increase . In some situations, the algorithm proposed obtained more efficient results than the CW algorithm. The key factor was a reduction in the number of mistakes (one way routes and in the level of result variation.

  17. Developing New Tourism routes in Coastal Areas

    OpenAIRE

    Flognfeldt, Thor

    2013-01-01

    For Norwegians the name of our country is based on a route - "the way to the North" - and this was not a built route but using of the coast-line itself. As long as the boats and ships were the main means of travel this coastal way - "Nor-way" - was the main communication basis for most people, and for transport of goods. But even in the interior of the country, water, namely rivers and lakes were the main structures for communication. The lakes were most efficient for transport during the col...

  18. Vessels Route Planning Problem with Uncertain Data

    Directory of Open Access Journals (Sweden)

    Tomasz Neumann

    2016-09-01

    Full Text Available The purpose of this paper is to find a solution for route planning in a transport networks, where the costs of tracks, factor of safety and travel time are ambiguous. This approach is based on the Dempster-Shafer theory and well known Dijkstra's algorithm. In this approach important are the influencing factors of the mentioned coefficients using uncertain possibilities presented by probability intervals. Based on these intervals the quality intervals of each route can be determined. Applied decision rules can be described by the end user.

  19. Reconfigurable Robust Routing for Mobile Outreach Network

    Science.gov (United States)

    Lin, Ching-Fang

    2010-01-01

    The Reconfigurable Robust Routing for Mobile Outreach Network (R3MOO N) provides advanced communications networking technologies suitable for the lunar surface environment and applications. The R3MOON techn ology is based on a detailed concept of operations tailored for luna r surface networks, and includes intelligent routing algorithms and wireless mesh network implementation on AGNC's Coremicro Robots. The product's features include an integrated communication solution inco rporating energy efficiency and disruption-tolerance in a mobile ad h oc network, and a real-time control module to provide researchers an d engineers a convenient tool for reconfiguration, investigation, an d management.

  20. Spallation reactions; Reactions de spallation

    Energy Technology Data Exchange (ETDEWEB)

    Cugon, J.

    1996-12-31

    Spallation reactions dominate the interactions of hadrons with nuclei in the GeV range (from {approx} 0.1 to {approx} 10 GeV). They correspond to a sometimes important ejection of light particles leaving most of the time a residue of mass commensurate with the target mass. The main features of the experimental data are briefly reviewed. The most successful theoretical model, namely the intranuclear cascade + evaporation model, is presented. Its physical content, results and possible improvements are critically discussed. Alternative approaches are shortly reviewed. (author). 84 refs.

  1. Substrate-Directed Catalytic Selective Chemical Reactions.

    Science.gov (United States)

    Sawano, Takahiro; Yamamoto, Hisashi

    2018-05-04

    The development of highly efficient reactions at only the desired position is one of the most important subjects in organic chemistry. Most of the reactions in current organic chemistry are reagent- or catalyst-controlled reactions, and the regio- and stereoselectivity of the reactions are determined by the inherent nature of the reagent or catalyst. In sharp contrast, substrate-directed reaction determines the selectivity of the reactions by the functional group on the substrate and can strictly distinguish sterically and electronically similar multiple reaction sites in the substrate. In this Perspective, three topics of substrate-directed reaction are mainly reviewed: (1) directing group-assisted epoxidation of alkenes, (2) ring-opening reactions of epoxides by various nucleophiles, and (3) catalytic peptide synthesis. Our newly developed synthetic methods with new ligands including hydroxamic acid derived ligands realized not only highly efficient reactions but also pinpointed reactions at the expected position, demonstrating the substrate-directed reaction as a powerful method to achieve the desired regio- and stereoselective functionalization of molecules from different viewpoints of reagent- or catalyst-controlled reactions.

  2. Micron-sized columnar grains of CH3NH3PbI3 grown by solvent-vapor assisted low-temperature (75 °C) solid-state reaction: The role of non-coordinating solvent-vapor

    Science.gov (United States)

    Zheng, Huifeng; Liu, Yangqiao; Sun, Jing

    2018-04-01

    The preparation of hybrid perovskite films with large columnar grains via low-temperature solid-state reaction remains a big challenge. Conventional solvent annealing using DMF, DMSO and ethanol, etc. fails to work effectively at low temperature (solar cells based on benzyl-alcohol-vapor annealing (75 °C), delivered much higher photovoltaic performance, better stability and smaller hysteresis than those based on conventional thermal annealing. Additionally, a champion power conversion efficiency (PCE) of 15.1% was obtained and the average PCE reached 12.2% with a tiny deviation. Finally, the mechanism of solvent annealing with non-coordinating solvent was discussed. Moreover, we revealed that high polarity and high boiling point of the solvent used for generating vapor, was critical to grow micron-sized columnar grains at such a low temperature (75 °C). This work will contribute to understanding the mechanism of grain growth in solvent annealing and improving its facility and effectiveness.

  3. Ionic Liquid-Assisted Synthesis of Nanoscale (MoS2)x(SnO2)1-x on Reduced Graphene Oxide for the Electrocatalytic Hydrogen Evolution Reaction.

    Science.gov (United States)

    Ravula, Sudhir; Zhang, Chi; Essner, Jeremy B; Robertson, J David; Lin, Jian; Baker, Gary A

    2017-03-08

    Layered transition metal dichalcogenides (TMDs) have attracted increased attention due to their enhanced hydrogen evolution reaction (HER) performance. More specifically, ternary TMD nanohybrids, such as MoS 2(1-x) Se 2x or bimetallic sulfides, have arisen as promising electrocatalysts compared to MoS 2 and MoSe 2 due to their electronic, morphologic, and size tunabilities. Herein, we report the successful synthesis of few-layered MoS 2 /rGO, SnS 2 /rGO, and (MoS 2 ) x (SnO 2 ) 1-x /rGO nanohybrids anchored on reduced graphene oxide (rGO) through a facile hydrothermal reaction in the presence of ionic liquids as stabilizing, delayering agents. Spectroscopic and microscopic techniques (electron microscopy, X-ray diffraction, Raman spectroscopy, neutron activation analysis, and UV-vis spectrophotometry) are used to validate the hierarchical properties, phase identity, and the smooth compositional tunability of the (MoS 2 ) x (SnO 2 ) 1-x /rGO nanohybrids. Linear sweep voltammetry measurements reveal that incorporation of Sn into the ternary nanohybrids (as a discrete SnO 2 phase) greatly reduces the overpotential by 90-130 mV relative to the MoS 2 electrocatalyst. Significantly, the (MoS 2 ) 0.6 (SnO 2 ) 0.4 /rGO nanohybrid displays superior catalytic performance over MoS 2 alone, exhibiting a low overpotential (η 10 ) of 263 ± 5 mV and a small Tafel slope of 50.8 mV dec -1 . The hybrid catalyst shows high stability for the HER in acidic solutions, with negligible activity loss after 1000 cycles. The hierarchical structures and large surface areas possessing exposed, active edge sites make few-layered (MoS 2 ) x (SnO 2 ) 1-x /rGO nanohybrids promising nonprecious metal electrocatalysts for the HER.

  4. Pressure-Induced Polymerization of Acetylene: Structure-Directed Stereoselectivity and a Possible Route to Graphane.

    Science.gov (United States)

    Sun, Jiangman; Dong, Xiao; Wang, Yajie; Li, Kuo; Zheng, Haiyan; Wang, Lijuan; Cody, George D; Tulk, Christopher A; Molaison, Jamie J; Lin, Xiaohuan; Meng, Yufei; Jin, Changqing; Mao, Ho-Kwang

    2017-06-01

    Geometric isomerism in polyacetylene is a basic concept in chemistry textbooks. Polymerization to cis-isomer is kinetically preferred at low temperature, not only in the classic catalytic reaction in solution but also, unexpectedly, in the crystalline phase when it is driven by external pressure without a catalyst. Until now, no perfect reaction route has been proposed for this pressure-induced polymerization. Using in situ neutron diffraction and meta-dynamic simulation, we discovered that under high pressure, acetylene molecules react along a specific crystallographic direction that is perpendicular to those previously proposed. Following this route produces a pure cis-isomer and more surprisingly, predicts that graphane is the final product. Experimentally, polycyclic polymers with a layered structure were identified in the recovered product by solid-state nuclear magnetic resonance and neutron pair distribution functions, which indicates the possibility of synthesizing graphane under high pressure. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Shape-controlled synthesis and properties of manganese sulfide microcrystals via a biomolecule-assisted hydrothermal process

    Energy Technology Data Exchange (ETDEWEB)

    Jiang Jinghui; Yu Runnan; Zhu Jianyu; Yi Ran; Qiu Guanzhou [School of Resources Processing and Bioengineering, Central South University, Changsha, Hunan 410083 (China); He Yuehui [State Key Laboratory of Powder Metallurgy, Central South University, Changsha, Hunan 410083 (China); Liu Xiaohe, E-mail: liuxh@mail.csu.edu.cn [School of Resources Processing and Bioengineering, Central South University, Changsha, Hunan 410083 (China); State Key Laboratory of Powder Metallurgy, Central South University, Changsha, Hunan 410083 (China)

    2009-06-15

    An effective biomolecule-assisted synthetic route has been successfully developed to prepare {gamma}-manganese sulfide (MnS) microtubes under hydrothermal conditions. In the synthetic system, soluble hydrated manganese chloride was employed to supply Mn source and L-cysteine was used as precipitator and complexing reagent. Sea urchin-like {gamma}-MnS and octahedron-like {alpha}-MnS microcrystals could also be selectively obtained by adjusting the process parameters such as hydrothermal temperature and reaction time. The phase structures, morphologies and properties of the as-prepared products were investigated in detail by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersion spectroscopy (EDS), and photoluminescence spectra (PL). The photoluminescence studies exhibited the correlations between the morphology, size, and shape structure of MnS microcrystals and its optical properties. The formation mechanisms of manganese sulfide microcrystals were discussed based on the experimental results.

  6. Obsidian trade routes in the mayan area.

    Science.gov (United States)

    Hammond, N

    1972-12-08

    Obsidian from two sources in highland Guatemala has been found at 23 sites of the Classic Mayan civilization, mainly in the nonvolcanic lowlands to the north. The distribution, together with trade routes suggested by topography and documentary sources, suggests efficient waterborne transport and competition between sources for the lowland market.

  7. Optimal solutions for routing problems with profits

    NARCIS (Netherlands)

    Archetti, C.; Bianchessi, N.; Speranza, M. G.

    2013-01-01

    In this paper, we present a branch-and-price algorithm to solve two well-known vehicle routing problems with profits, the Capacitated Team Orienteering Problem and the Capacitated Profitable Tour Problem. A restricted master heuristic is applied at each node of the branch-and-bound tree in order to

  8. Routing in Networks with Random Topologies

    Science.gov (United States)

    Bambos, Nicholas

    1997-01-01

    We examine the problems of routing and server assignment in networks with random connectivities. In such a network the basic topology is fixed, but during each time slot and for each of tis input queues, each server (node) is either connected to or disconnected from each of its queues with some probability.

  9. Automated Flight Routing Using Stochastic Dynamic Programming

    Science.gov (United States)

    Ng, Hok K.; Morando, Alex; Grabbe, Shon

    2010-01-01

    Airspace capacity reduction due to convective weather impedes air traffic flows and causes traffic congestion. This study presents an algorithm that reroutes flights in the presence of winds, enroute convective weather, and congested airspace based on stochastic dynamic programming. A stochastic disturbance model incorporates into the reroute design process the capacity uncertainty. A trajectory-based airspace demand model is employed for calculating current and future airspace demand. The optimal routes minimize the total expected traveling time, weather incursion, and induced congestion costs. They are compared to weather-avoidance routes calculated using deterministic dynamic programming. The stochastic reroutes have smaller deviation probability than the deterministic counterpart when both reroutes have similar total flight distance. The stochastic rerouting algorithm takes into account all convective weather fields with all severity levels while the deterministic algorithm only accounts for convective weather systems exceeding a specified level of severity. When the stochastic reroutes are compared to the actual flight routes, they have similar total flight time, and both have about 1% of travel time crossing congested enroute sectors on average. The actual flight routes induce slightly less traffic congestion than the stochastic reroutes but intercept more severe convective weather.

  10. Graphical route information on variable message signs

    NARCIS (Netherlands)

    Alkim, T.P.; Mede, P.H.J. van der; Janssen, W.H.

    2002-01-01

    Reports on experiments in the Netherlands on the use of graphical route information panels (GRIP) as part of variable message systems (VMS) providing information to drivers. GRIP appear to be as safe as regular VMS. Digestion of the information presented is initially quicker for regular VMS, but

  11. A Decentralized Approach to Formation Flight Routing

    NARCIS (Netherlands)

    Visser, H.G.; Lopes dos Santos, Bruno F.; Verhagen, C.M.A.

    2016-01-01

    This paper describes the development of an optimization-based cooperative planning system for the efficient routing and scheduling of flight formations. This study considers the use of formation flight as a means to reduce the overall fuel consumption of civil aviation in long-haul operations. It

  12. Variable-speed, portable routing skate

    Science.gov (United States)

    Pesch, W. A.

    1967-01-01

    Lightweight, portable, variable-speed routing skate is used on heavy metal subassemblies which are impractical to move to a stationary machine. The assembly, consisting of the housing with rollers, router, and driving mechanism with transmission, weighs about forty pounds. Both speed and depth of cut are adjustable.

  13. Traffic disruption route Einstein near building 170

    CERN Multimedia

    A Lopez - TS/CE

    2005-01-01

    The TS/CE Group informs you that, for the duration of the work at Building 170, there may be some disruption to traffic on route Einstein in the vicinity of Building 170. The work is due to take place from the 14th to 18th February. For more information, please contact 165029. A. Lopez TS/CE

  14. Phone Routing using the Dynamic Memory Model

    DEFF Research Database (Denmark)

    Bendtsen, Claus Nicolaj; Krink, Thiemo

    2002-01-01

    In earlier studies a genetic algorithm (GA) extended with the dynamic memory model has shown remarkable performance on real-world-like problems. In this paper we experiment with routing in communication networks and show that the dynamic memory GA performs remarkable well compared to ant colony...

  15. A Geographical Heuristic Routing Protocol for VANETs

    Science.gov (United States)

    Urquiza-Aguiar, Luis; Tripp-Barba, Carolina; Aguilar Igartua, Mónica

    2016-01-01

    Vehicular ad hoc networks (VANETs) leverage the communication system of Intelligent Transportation Systems (ITS). Recently, Delay-Tolerant Network (DTN) routing protocols have increased their popularity among the research community for being used in non-safety VANET applications and services like traffic reporting. Vehicular DTN protocols use geographical and local information to make forwarding decisions. However, current proposals only consider the selection of the best candidate based on a local-search. In this paper, we propose a generic Geographical Heuristic Routing (GHR) protocol that can be applied to any DTN geographical routing protocol that makes forwarding decisions hop by hop. GHR includes in its operation adaptations simulated annealing and Tabu-search meta-heuristics, which have largely been used to improve local-search results in discrete optimization. We include a complete performance evaluation of GHR in a multi-hop VANET simulation scenario for a reporting service. Our study analyzes all of the meaningful configurations of GHR and offers a statistical analysis of our findings by means of MANOVA tests. Our results indicate that the use of a Tabu list contributes to improving the packet delivery ratio by around 5% to 10%. Moreover, if Tabu is used, then the simulated annealing routing strategy gets a better performance than the selection of the best node used with carry and forwarding (default operation). PMID:27669254

  16. Scenemash: multimodal route summarization for city exploration

    NARCIS (Netherlands)

    Berg, J. van den; Rudinac, S.; Worring, M.

    2016-01-01

    The potential of mining tourist information from social multimedia data gives rise to new applications offering much richer impressions of the city. In this paper we propose Scenemash, a system that generates multimodal summaries of multiple alternative routes between locations in a city. To get

  17. ROUTE PLAN DESIGNER FOR TRACTOR GUIDANCE SYSTEMS

    DEFF Research Database (Denmark)

    Sveistrup, Daniel; Jørgensen, Rasmus Nyholm; Green, Ole

    2010-01-01

    Earlier works have shown field trial designs to be very labor extensive, even when combining autoguidancesystems with conventional machinery.Designing routes for semi-automated systems in a controlled manner is both resource demandingand complicated. Different types of auto-guidance systems vary ...

  18. Porcelain tiles by the dry route

    Directory of Open Access Journals (Sweden)

    Boschi, A. O.

    2010-10-01

    Full Text Available 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.

    En Brasil, en este momento segundo productor mundial, el 70% de los pavimentos cerámicos se obtiene por vía seca. Una de las razones fundamentales se debe a que esta vía supone un consumo energético inferior, en un 30%, a la via húmeda tradicional. La creciente preocupación mundial sobre los problemas medioambientales y el reconocimiento del papel central que juega el agua en este proceso han favorecido el desarrollo de la vía seca. En este contexto, el objetivo del presente trabajo es estudiar la viabilidad de la producción de pavimentos porcelánicos de alta calidad por vía seca. Una breve comparación entre ambas vías, en las condiciones standard de producción vigentes para producciones que no son de porcelánico, indican que existen dos diferencias substanciales; el tamaño de

  19. Kinetics of hydrogen isotope exchange reactions

    International Nuclear Information System (INIS)

    Gold, V.; McAdam, M.E.

    1975-01-01

    Under the influence of tritium β-radiation, 1,4-dioxan undergoes hydrogen exchange with the solvent water. The inhibition of the reaction by known electron scavengers (Ag + , Cu 2+ , Ni 2+ , Co 2+ , Zn 2+ , H 3 + O) and also by species with high reactivity towards hydroxyl radicals but negligible reactivity towards solvated electrons (N 3 - , Br - , SCN - ) has been examined in detail. γ-irradiation similarly induces hydrogen exchange. The action of scavengers is interpreted as requiring the involvement of two separately scavengeable primary radiolysis products in the sequence of reactions leading to exchange. The presence of electron scavengers, even at high concentration, does not totally inhibit the exchange, and a secondary exchange route, involving a low vacancy state of inhibitor cations, is considered responsible for the 'unscavengeable' portion of the reaction, by providing an alternative exchange route. Analogies are drawn between the exchange reaction and other radiation-induced reactions that are thought to involve spur processes. Some implication of radiation-chemical studies in water-alcohol mixtures are indicated. (author)

  20. Chain reaction

    International Nuclear Information System (INIS)

    Balogh, Brian.

    1991-01-01

    Chain Reaction is a work of recent American political history. It seeks to explain how and why America came to depend so heavily on its experts after World War II, how those experts translated that authority into political clout, and why that authority and political discretion declined in the 1970s. The author's research into the internal memoranda of the Atomic Energy Commission substantiates his argument in historical detail. It was not the ravages of American anti-intellectualism, as so many scholars have argued, that brought the experts back down to earth. Rather, their decline can be traced to the very roots of their success after World War II. The need to over-state anticipated results in order to garner public support, incessant professional and bureaucratic specialization, and the sheer proliferation of expertise pushed arcane and insulated debates between experts into public forums at the same time that a broad cross section of political participants found it easier to gain access to their own expertise. These tendencies ultimately undermined the political influence of all experts. (author)

  1. Heparin for assisted reproduction.

    Science.gov (United States)

    Akhtar, Muhammad A; Sur, Shyamaly; Raine-Fenning, Nick; Jayaprakasan, Kannamannadiar; Thornton, Jim G; Quenby, Siobhan

    2013-08-17

    heterogeneity). There was also a significant improvement in the clinical pregnancy rate with use of LMWH (OR 1.61, 95% CI 1.03 to 2.53, three studies, 386 women, I(2) = 29%, very low quality evidence with low heterogeneity).However these findings should be interpreted with extreme caution as they were dependent upon the choice of statistical method: they were no longer statistically significant when a random-effects model was used.Adverse events were poorly reported in all included studies, with no comparative data available. However, LMWH did cause adverse effects including bruising, ecchymosis, bleeding, thrombocytopenia and allergic reactions. It appeared that these adverse effects were increased if heparin therapy was used over a longer duration. The results of this Cochrane review of three randomised controlled trials with a total of 386 women suggested that peri-implantation LMWH in assisted reproduction treatment (ART) cycles may improve the live birth rate in women undergoing assisted reproduction. However, these results were dependent on small low quality studies with substantial heterogeneity, and were sensitive to the choice of statistical model. There were side effects reported with use of heparin, including bruising and bleeding, and no reliable data on long-term effects. The results do not justify this use of heparin outside well-conducted research trials.These findings need to be further investigated with well-designed, adequately powered, double-blind, randomised, placebo-controlled, multicentre trials. Further investigations could also focus on the effects of the local (uterine) and not systemic application of heparin during ART.

  2. Route assessment using comparative risk factors integrated through a GIS

    International Nuclear Information System (INIS)

    Toth, D.M.; O'Connell, W.J.

    1996-01-01

    The assessment of potential alternative routes for the shipment of spent nuclear fuel was simplified through the use of comparative risk factors evaluated using detailed route and environmental attributes. The route characteristics, integrated into risk measures, vary strongly with location and were developed from national, state, and local sources. The route data and evaluation were managed using a geographic information system (GIS). An assessment of four real North Florida routes was performed and an interstate highway route exhibited the lowest risk based on the application of the risk factors

  3. Intelligent routing protocol for ad hoc wireless network

    Science.gov (United States)

    Peng, Chaorong; Chen, Chang Wen

    2006-05-01

    A novel routing scheme for mobile ad hoc networks (MANETs), which combines hybrid and multi-inter-routing path properties with a distributed topology discovery route mechanism using control agents is proposed in this paper. In recent years, a variety of hybrid routing protocols for Mobile Ad hoc wireless networks (MANETs) have been developed. Which is proactively maintains routing information for a local neighborhood, while reactively acquiring routes to destinations beyond the global. The hybrid protocol reduces routing discovery latency and the end-to-end delay by providing high connectivity without requiring much of the scarce network capacity. On the other side the hybrid routing protocols in MANETs likes Zone Routing Protocol still need route "re-discover" time when a route between zones link break. Sine the topology update information needs to be broadcast routing request on local zone. Due to this delay, the routing protocol may not be applicable for real-time data and multimedia communication. We utilize the advantages of a clustering organization and multi-routing path in routing protocol to achieve several goals at the same time. Firstly, IRP efficiently saves network bandwidth and reduces route reconstruction time when a routing path fails. The IRP protocol does not require global periodic routing advertisements, local control agents will automatically monitor and repair broke links. Secondly, it efficiently reduces congestion and traffic "bottlenecks" for ClusterHeads in clustering network. Thirdly, it reduces significant overheads associated with maintaining clusters. Fourthly, it improves clusters stability due to dynamic topology changing frequently. In this paper, we present the Intelligent Routing Protocol. First, we discuss the problem of routing in ad hoc networks and the motivation of IRP. We describe the hierarchical architecture of IRP. We describe the routing process and illustrate it with an example. Further, we describe the control manage

  4. A Survey of Routing Protocols in Wireless Body Sensor Networks

    Science.gov (United States)

    Bangash, Javed Iqbal; Abdullah, Abdul Hanan; Anisi, Mohammad Hossein; Khan, Abdul Waheed

    2014-01-01

    Wireless Body Sensor Networks (WBSNs) constitute a subset of Wireless Sensor Networks (WSNs) responsible for monitoring vital sign-related data of patients and accordingly route this data towards a sink. In routing sensed data towards sinks, WBSNs face some of the same routing challenges as general WSNs, but the unique requirements of WBSNs impose some more constraints that need to be addressed by the routing mechanisms. This paper identifies various issues and challenges in pursuit of effective routing in WBSNs. Furthermore, it provides a detailed literature review of the various existing routing protocols used in the WBSN domain by discussing their strengths and weaknesses. PMID:24419163

  5. Comparison of routing metrics for wireless mesh networks

    CSIR Research Space (South Africa)

    Nxumalo, SL

    2011-09-01

    Full Text Available in each and every relay node so as to find the next hop for the packet. A routing metric is simply a measure used for selecting the best path, used by a routing protocol. Figure 2 shows the relationship between a routing protocol and the routing... on its QoS-awareness level. The routing metrics that considered QoS the most were selected from each group. This section discusses the four routing metrics that were compared in this paper, which are: hop count (HOP), expected transmission count (ETX...

  6. Role of Re in Pt-Re/TiO2 catalyst for water gas shift reaction: A mechanistic and kinetic study.

    NARCIS (Netherlands)

    Azzam, K.G.H.; Babych, Igor V.; Seshan, Kulathuiyer; Lefferts, Leonardus

    2008-01-01

    Transient kinetic studies and in situ FTIR spectroscopy were used to follow the reaction sequences that occur during water gas shift (WGS) reaction over Pt–Re/TiO2 catalyst. Results pointed to contributions of an associative formate route with redox regeneration and two classical redox routes

  7. PNW River Reach Files -- 1:100k LLID Routed Streams (routes)

    Data.gov (United States)

    Pacific States Marine Fisheries Commission — This feature class includes the ROUTE features from the 2001 version of the PNW River Reach files Arc/INFO coverage. Separate, companion feature classes are also...

  8. Assisted Vaginal Delivery

    Science.gov (United States)

    ... Education & Events Advocacy For Patients About ACOG Assisted Vaginal Delivery Home For Patients Search FAQs Assisted Vaginal ... Vaginal Delivery FAQ192, February 2016 PDF Format Assisted Vaginal Delivery Labor, Delivery, and Postpartum Care What is ...

  9. Routing Protocols for Underwater Wireless Sensor Networks: Taxonomy, Research Challenges, Routing Strategies and Future Directions.

    Science.gov (United States)

    Khan, Anwar; Ali, Ihsan; Ghani, Abdullah; Khan, Nawsher; Alsaqer, Mohammed; Rahman, Atiq Ur; Mahmood, Hasan

    2018-05-18

    Recent research in underwater wireless sensor networks (UWSNs) has gained the attention of researchers in academia and industry for a number of applications. They include disaster and earthquake prediction, water quality and environment monitoring, leakage and mine detection, military surveillance and underwater navigation. However, the aquatic medium is associated with a number of limitations and challenges: long multipath delay, high interference and noise, harsh environment, low bandwidth and limited battery life of the sensor nodes. These challenges demand research techniques and strategies to be overcome in an efficient and effective fashion. The design of routing protocols for UWSNs is one of the promising solutions to cope with these challenges. This paper presents a survey of the routing protocols for UWSNs. For the ease of description, the addressed routing protocols are classified into two groups: localization-based and localization-free protocols. These groups are further subdivided according to the problems they address or the major parameters they consider during routing. Unlike the existing surveys, this survey considers only the latest and state-of-the-art routing protocols. In addition, every protocol is described in terms of its routing strategy and the problem it addresses and solves. The merit(s) of each protocol is (are) highlighted along with the cost. A description of the protocols in this fashion has a number of advantages for researchers, as compared to the existing surveys. Firstly, the description of the routing strategy of each protocol makes its routing operation easily understandable. Secondly, the demerit(s) of a protocol provides (provide) insight into overcoming its flaw(s) in future investigation. This, in turn, leads to the foundation of new protocols that are more intelligent, robust and efficient with respect to the desired parameters. Thirdly, a protocol can be selected for the appropriate application based on its described

  10. Canine assisted reading

    OpenAIRE

    Sever, Jerneja

    2016-01-01

    The diploma thesis presents various aspects of animals included in animal-assisted interventions. In theoretical part, I introduced different possible ways of animal-assisted interventions: animal-assisted therapy, animal-assisted activities and animal-assisted education. Animals became common visitors in educational settings all over the world. I presented positive influences on various aspects of human life, as well limitations when animal-assisted interventions are not possible to perform ...

  11. Route Monopolie and Optimal Nonlinear Pricing

    Science.gov (United States)

    Tournut, Jacques

    2003-01-01

    To cope with air traffic growth and congested airports, two solutions are apparent on the supply side: 1) use larger aircraft in the hub and spoke system; or 2) develop new routes through secondary airports. An enlarged route system through secondary airports may increase the proportion of route monopolies in the air transport market.The monopoly optimal non linear pricing policy is well known in the case of one dimension (one instrument, one characteristic) but not in the case of several dimensions. This paper explores the robustness of the one dimensional screening model with respect to increasing the number of instruments and the number of characteristics. The objective of this paper is then to link and fill the gap in both literatures. One of the merits of the screening model has been to show that a great varieD" of economic questions (non linear pricing, product line choice, auction design, income taxation, regulation...) could be handled within the same framework.VCe study a case of non linear pricing (2 instruments (2 routes on which the airline pro_ddes customers with services), 2 characteristics (demand of services on these routes) and two values per characteristic (low and high demand of services on these routes)) and we show that none of the conclusions of the one dimensional analysis remain valid. In particular, upward incentive compatibility constraint may be binding at the optimum. As a consequence, they may be distortion at the top of the distribution. In addition to this, we show that the optimal solution often requires a kind of form of bundling, we explain explicitly distortions and show that it is sometimes optimal for the monopolist to only produce one good (instead of two) or to exclude some buyers from the market. Actually, this means that the monopolist cannot fully apply his monopoly power and is better off selling both goods independently.We then define all the possible solutions in the case of a quadratic cost function for a uniform

  12. Congestion control and routing over satellite networks

    Science.gov (United States)

    Cao, Jinhua

    Satellite networks and transmissions find their application in fields of computer communications, telephone communications, television broadcasting, transportation, space situational awareness systems and so on. This thesis mainly focuses on two networking issues affecting satellite networking: network congestion control and network routing optimization. Congestion, which leads to long queueing delays, packet losses or both, is a networking problem that has drawn the attention of many researchers. The goal of congestion control mechanisms is to ensure high bandwidth utilization while avoiding network congestion by regulating the rate at which traffic sources inject packets into a network. In this thesis, we propose a stable congestion controller using data-driven, safe switching control theory to improve the dynamic performance of satellite Transmission Control Protocol/Active Queue Management (TCP/AQM) networks. First, the stable region of the Proportional-Integral (PI) parameters for a nominal model is explored. Then, a PI controller, whose parameters are adaptively tuned by switching among members of a given candidate set, using observed plant data, is presented and compared with some classical AQM policy examples, such as Random Early Detection (RED) and fixed PI control. A new cost detectable switching law with an interval cost function switching algorithm, which improves the performance and also saves the computational cost, is developed and compared with a law commonly used in the switching control literature. Finite-gain stability of the system is proved. A fuzzy logic PI controller is incorporated as a special candidate to achieve good performance at all nominal points with the available set of candidate controllers. Simulations are presented to validate the theory. An effocient routing algorithm plays a key role in optimizing network resources. In this thesis, we briefly analyze Low Earth Orbit (LEO) satellite networks, review the Cross Entropy (CE

  13. Route Fidelity during Marine Megafauna Migration

    Directory of Open Access Journals (Sweden)

    Travis W. Horton

    2017-12-01

    Full Text Available The conservation and protection of marine megafauna require robust knowledge of where and when animals are located. Yet, our ability to predict animal distributions in space and time remains limited due to difficulties associated with studying elusive animals with large home ranges. The widespread deployment of satellite telemetry technology creates unprecedented opportunities to remotely monitor animal movements and to analyse the spatial and temporal trajectories of these movements from a variety of geophysical perspectives. Reproducible patterns in movement trajectories can help elucidate the potential mechanisms by which marine megafauna navigate across vast expanses of open-ocean. Here, we present an empirical analysis of humpback whale (Megaptera novaeangliae, great white shark (Carcharodon carcharias, and northern elephant seal (Mirounga angustirostris satellite telemetry-derived route fidelity movements in magnetic and gravitational coordinates. Our analyses demonstrate that: (1 humpback whales, great white sharks and northern elephant seals are capable of performing route fidelity movements across millions of square kilometers of open ocean with a spatial accuracy of better than 150 km despite temporal separations as long as 7 years between individual movements; (2 route fidelity movements include significant (p < 0.05 periodicities that are comparable in duration to the lunar cycles and semi-cycles; (3 latitude and bedrock-dependent gravitational cues are stronger predictors of route fidelity movements than spherical magnetic coordinate cues when analyzed with respect to the temporally dependent moon illumination cycle. We further show that both route fidelity and non-route fidelity movement trajectories, for all three species, describe overlapping in-phase or antiphase sinusoids when individual movements are normalized to the gravitational acceleration present at migratory departure sites. Although these empirical results provide an

  14. Novel synthetic route to molybdenum hydrido-thiocarbamoyl and hydrosulfido-carbyne complexes by reactions of trans-Mo(N{sub 2}){sub 2}(R{sub 2}PC{sub 2}H{sub 4}PR{sub 2}){sub 2} with N,N-dimethylthioformamide

    Energy Technology Data Exchange (ETDEWEB)

    Luo, X.L.; Kubas, G.J.; Burns, C.J.; Butcher, R.J. [Los Alamos National Lab., NM (United States)

    1995-07-01

    The reactions of bis(dinitrogen)molybdenum complexes trans-Mo(N{sub 2}){sub 2}(R{sub 2}PC{sub 2}H{sub 4}PR{sub 2}){sub 2} (R = Ph, Et) with N,N-dimethylthioformamide (HC(S)NMe{sub 2}) in refluxing benzene under argon give the molybdenum hydrido-thiocarbamoyl complexes MoH({eta}{sup 2}-C(S)NMe{sub 2})(R{sub 2}PC{sub 2}H{sub 4}PR{sub 2}){sub 2} (R = Ph (1a), Et (1b)). On heating at 125{degree}C in toluene solutions, compounds 1a and 1b rearrange to form the molybdenum hydrosulfido-aminocarbyne complexes trans-Mo(SH)-(=CNMe{sub 2})(R{sub 2}PC{sub 2}H{sub 4}PR{sub 2}){sub 2} (R = Ph (2a), Et (2b)). A mechanism is proposed for this thermal rearrangement which involves migration of the hydride ligand from molybdenum to the sulfur atom of the thiocarbamoyl ligand to give the 16-electron Fischer carbene intermediate Mo-(=C(SH)NMe{sub 2})(R{sub 2}PC{sub 2}H{sub 4}PR{sub 2}){sub 2}, followed by migration of the hydrosulfido group from the carbene carbon to molybdenum. The molecular structures of compounds 1a and 2a have been determined by single-crystal X-ray diffraction studies. 30 refs., 4 figs., 4 tabs.

  15. RSRP: A Robust Secure Routing Protocol in MANET

    Directory of Open Access Journals (Sweden)

    Sinha Ditipriya

    2014-05-01

    Full Text Available In this paper, we propose a novel algorithm RSRP to build a robust secure routing protocol in mobile ad-hoc networks (MANETs. This algorithm is based on some basic schemes such as RSA_CRT for encryption and decryption of messages; CRT for safety key generation, Shamir’s secret sharing principle for generation of secure routes. Those routes which are free from any malicious node and which belong to the set of disjoint routes between a source-destination pair are considered as probable routes. Shamir’s secret sharing principle is applied on those probable routes to obtain secure routes. Finally, most trustworthy and stable route is selected among those secure routes. Selection of the final route depends on some criteria of the nodes present in a route e.g.: battery power, mobility and trust value. In addition, complexity of key generation is reduced to a large extent by using RSA-CRT instead of RSA. In turn, the routing becomes less expensive and most secure and robust one. Performance of this routing protocol is then compared with non-secure routing protocols (AODV and DSR, secure routing scheme using secret sharing, security routing protocol using ZRP and SEAD depending on basic characteristics of these protocols. All such comparisons show that RSRP shows better performance in terms of computational cost, end-to-end delay and packet dropping in presence of malicious nodes in the MANET, keeping the overhead in terms of control packets same as other secure routing protocols.

  16. A decision support system for mission-based ship routing considering multiple performance criteria

    International Nuclear Information System (INIS)

    Dong, You; Frangopol, Dan M.; Sabatino, Samantha

    2016-01-01

    It is crucial to evaluate the risk associated with marine vessels subjected to inclement weather and sea conditions when developing a decision support system for ship routing. The generalized decision making framework developed in this paper performs a variety of tasks, including, but not limited to quantifying the flexural and fatigue performance of ship structures and employing multi-attribute utility theory to evaluate ship mission performance. A structural reliability approach is utilized to compute the probability of failure considering the uncertainties in structural capacity and load effects; specifically, effects of flexural and fatigue damage are investigated. The expected repair cost, cumulative fatigue damage, total travel time, and carbon dioxide emissions associated with ship routing are considered as consequences within the risk assessment procedure adopted in this paper. Additionally, the decision maker’s risk attitude is integrated into the presented approach by employing utility theory. The presented methodology can assist decision makers in making informed decisions concerning ship routing. In order to illustrate its capabilities the approach is applied to the Joint High-speed Sealift Ship. - Highlights: • Multi-attribute utility theory is proposed for the ship routing decision making. • Spectral-based fatigue damage and repair loss are computed. • Travel time and CO_2 emissions are incorporated within the decision making process. • The attitude of the decision maker has significant effects on the utility value.

  17. A novel route to synthesis of glycerol dimethyl ether from epichlorohydrin with high selectivity

    International Nuclear Information System (INIS)

    Ding, Xiaoshu; Liu, Hao; Yang, Qiusheng; Li, Naihua; Dong, Xiangmo; Wang, Shufang; Zhao, Xinqiang; Wang, Yanji

    2014-01-01

    The effective utilization of glycerol, a by-product in the production of biodiesel, into useful chemicals is desirable from the viewpoint of green chemistry. With this in mind, a novel and highly selective route to synthesizing glycerol dimethyl ether (2,3-dimethoxy-1-propanol), a potential fuel additive, from glycerol was proposed. This route uses both glycerol and methanol as starting materials, takes epichlorohydrin as an intermediate product, and utilizes HCl as a recycling agent. Hereinto, the key step of this route is the reaction between epichlorohydrin and methanol to produce 2,3-dimethoxy-1-propanol which is identified by GC–MS, ESI-MS, IR and NMR. The thermodynamics of this reaction was analyzed and the result showed that the thermodynamics of a reaction was favorable and a high product yield was expected. The effect of various parameters such as kind of acid catalyst, molar ratio of epichlorohydrin to methanol, reaction temperature and reaction time was studied. Among various acid catalysts investigated, the acidic ionic liquid [HSO 3 -b-N(CH 3 ) 3 ]HSO 4 exhibited the highest activity and selectivity: conversion of epichlorohydrin of 100% and selectivity of 2,3-dimethoxy-1-propanol of 99% at 393 K, 10 h, an initial pressure of 0.1 MPa and a molar ratio of catalyst:ECH:CH 3 OH of 0.01:1:5. After the reaction, [HSO 3 -b-N(CH 3 ) 3 ]HSO 4 was separated by vacuum distillation and then reused for the next cycle directly. The results showed that the product selectivity remained at about 94% but the conversion of epichlorohydrin dropped to 75% after being used five times. Subsequently, a reaction mechanism for the synthesis of 2,3-dimethoxy-1-propanol from epichlorohydrin and methanol was proposed. - Highlights: • Epichlorohydrin was converted effectively into glycerol dimethyl ether used as potential fuel additive. • The selectivity of 99% and the conversion of 100% under the mild reaction condition. • The reaction was high product selectivity and

  18. 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...

  19. Fund allocation using capacitated vehicle routing problem

    Science.gov (United States)

    Mamat, Nur Jumaadzan Zaleha; Jaaman, Saiful Hafizah; Ahmad, Rokiah Rozita; Darus, Maslina

    2014-09-01

    In investment fund allocation, it is unwise for an investor to distribute his fund into several assets simultaneously due to economic reasons. One solution is to allocate the fund into a particular asset at a time in a sequence that will either maximize returns or minimize risks depending on the investor's objective. The vehicle routing problem (VRP) provides an avenue to this issue. VRP answers the question on how to efficiently use the available fleet of vehicles to meet a given service demand, subjected to a set of operational requirements. This paper proposes an idea of using capacitated vehicle routing problem (CVRP) to optimize investment fund allocation by employing data of selected stocks in the FTSE Bursa Malaysia. Results suggest that CRVP can be applied to solve the issue of investment fund allocation and increase the investor's profit.

  20. Latent factors and route choice behaviour

    DEFF Research Database (Denmark)

    Prato, Carlo Giacomo

    . A reliable dataset was prepared through measures of internal consistency and sampling adequacy, and data were analyzed with a proper application of factor analysis to the route choice context. For the dataset obtained from the survey, six latent constructs affecting driver behaviour were extracted and scores...... on each factor for each survey participant were calculated. Path generation algorithms were examined with respect to observed behaviour, through a measure of reproduction with deterministic techniques of the routes indicated in the answers to the survey. Results presented evidence that the majority...... and Link Nested Logit. Estimates were produced from model specifications that considered level-of-service, label and facility dummy variables. Moreover, a modelling framework was designed to represent drivers’ choices as affected by the latent constructs extracted with factor analysis. Previous experience...

  1. 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.

  2. 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.

  3. Design alternatives for wavelength routing networks

    Science.gov (United States)

    Miliotis, K.; Papadimitriou, G. I.; Pomportsis, A. S.

    2003-03-01

    This paper attempts to provide a high level overview of many of the technologies employed in optical networks with a focus on wavelength-routing networks. Optical networks involve a number of technologies from the physics of light through protocols and networks architectures. In fact there is so much technology and know-how that most people involved with optical networks only have a full understanding of the narrow area they deal with. We start first examining the principles that govern light and its use as a wave guide, and then turn our focus to the various components that constitute an optical network and conclude with the description of all optical networks and wavelength-routed networks in greater detail.

  4. Effective Privacy-Preserving Online Route Planning

    DEFF Research Database (Denmark)

    Vicente, Carmen Ruiz; Assent, Ira; Jensen, Christian S.

    2011-01-01

    An online Route Planning Service (RPS) computes a route from one location to another. Current RPSs such as Google Maps require the use of precise locations. However, some users may not want to disclose their source and destination locations due to privacy concerns. An approach that supplies fake...... privacy. The solution re-uses a standard online RPS rather than replicate this functionality, and it needs no trusted third party. The solution is able to compute the exact results without leaking of the exact locations to the RPS or un-trusted parties. In addition, we provide heuristics that reduce...... the number of times that the RPS needs to be queried, and we also describe how the accuracy and privacy requirements can be relaxed to achieve better performance. An empirical study offers insight into key properties of the approach....

  5. Rich Vehicle Routing Problems and Applications

    DEFF Research Database (Denmark)

    Wen, Min

    very short computational time on real-life data involving up to 200 pairs of suppliers and customers. The second problem we consider is a dynamic vehicle routing problem with multiple objectives over a planning horizon that consists of multiple periods. In this problem, customer orders are revealed...... the company’s solution in terms of all the objectives, including the travel time, customer waiting and daily workload balances, under the given constraints considered in the work. Finally, we address an integrated vehicle routing and driver scheduling problem, in which a large number of practical constraints....... The method is implemented and tested on real-life data involving up to 2000 orders. It is shown that the method is able to provide solutions of good quality within reasonable running time....

  6. Enabling Routes as Context in Mobile Services

    DEFF Research Database (Denmark)

    Brilingaite, Agne; Jensen, Christian Søndergaard; Zokaite, Nora

    With the continuing advances in wireless communications, geo-positioning, and portable electronics, an infrastructure is emerging that enables the delivery of on-line, location-enabled services to very large numbers of mobile users. A typical usage situation for mobile services is one characteriz...... and accumulates the routes of a user along with their usage patterns and that makes the routes available to services. Experiences from using the component on logs of GPS positions acquired from vehicles traveling within a real road network are reported....... by a small screen and no keyboard, and by the service being only a secondary focus of the user. Under such circumstances, it is particularly important to deliver the "right" information and service at the right time, with as little user interaction as possible. This may be achieved by making services context...

  7. ASR performance analysis of an experimental call routing system

    CSIR Research Space (South Africa)

    Modipa, T

    2009-11-01

    Full Text Available Call routing is an important application of Automatic Speech Recognition (ASR) technology. In this paper the authors discuss the main issues affecting the performance of a call routing system and describe the ASR component of the "Auto...

  8. Route Choice Model Based on Game Theory for Commuters

    Directory of Open Access Journals (Sweden)

    Licai Yang

    2016-06-01

    Full Text Available The traffic behaviours of commuters may cause traffic congestion during peak hours. Advanced Traffic Information System can provide dynamic information to travellers. Due to the lack of timeliness and comprehensiveness, the provided information cannot satisfy the travellers’ needs. Since the assumptions of traditional route choice model based on Expected Utility Theory conflict with the actual situation, a route choice model based on Game Theory is proposed to provide reliable route choice to commuters in actual situation in this paper. The proposed model treats the alternative routes as game players and utilizes the precision of predicted information and familiarity of traffic condition to build a game. The optimal route can be generated considering Nash Equilibrium by solving the route choice game. Simulations and experimental analysis show that the proposed model can describe the commuters’ routine route choice decisionexactly and the provided route is reliable.

  9. Routing protocols for wireless sensor networks: What the literature says?

    Directory of Open Access Journals (Sweden)

    Amit Sarkar

    2016-12-01

    Full Text Available Routing in Wireless Sensor Networks (WSNs plays a significant role in the field of environment-oriented monitoring, traffic monitoring, etc. Here, wide contributions that are made toward routing in WSN are explored. The paper mainly aims to categorize the routing problems and examines the routing-related optimization problems. For achieving the motive, 50 papers from the standard journals are collected and primarily reviewed in a chronological way. Later, various features that are related to energy, security, speed and reliability problems of routing are discussed. Subsequently, the literature is analyzed based on the simulation environment and experimental setup, awareness over the Quality of Service (QoS and the deployment against various applications. In addition, the optimization of the routing algorithms and the meta-heuristic study of routing optimization are explored. Routing is a vast area with numerous unsolved issues and hence, various research gaps along with future directions are also presented.

  10. Optimum Route Planning and Scheduling for Unmanned Aerial Vehicles

    National Research Council Canada - National Science Library

    Sonmezocak, Erkan; Kurt, Senol

    2008-01-01

    .... The route planning of UAVs is the most critical and challenging problem of wartime. This thesis will develop three algorithms to solve a model that produces executable routings in order to dispatch three Unmanned Aerial Vehicles (UAV...

  11. Advanced routing protocols for wireless networks

    CERN Document Server

    Campista , Miguel Elias Mitre

    2014-01-01

    This text introduces the principles of routing protocols and metrics as they affect wireless networking environments, specifically in urban areas. Timely because of the recent rise in small city life, this topic includes the consideration of ad hoc, mesh, vehicular, sensor, and delay tolerant networks. These approaches are each unique, and author Miguel Mitre Campista provides a thorough, but accessible, explanation of their individual characteristics for engineers, computer scientists, IT professionals, and curious Internet users.

  12. Latent variables and route choice behavior

    DEFF Research Database (Denmark)

    Prato, Carlo Giacomo; Bekhor, Shlomo; Pronello, Cristina

    2012-01-01

    In the last decade, a broad array of disciplines has shown a general interest in enhancing discrete choice models by considering the incorporation of psychological factors affecting decision making. This paper provides insight into the comprehension of the determinants of route choice behavior...... and bound algorithm. A hybrid model consists of measurement equations, which relate latent variables to measurement indicators and utilities to choice indicators, and structural equations, which link travelers’ observable characteristics to latent variables and explanatory variables to utilities. Estimation...

  13. Challenges in Enzymatic Route of Mannitol Production

    OpenAIRE

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

    2012-01-01

    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,...

  14. Routes towards supplier and production network internationalisation

    OpenAIRE

    A. CAMUFFO; FURLAN A; ROMANO P; VINELLI A

    2007-01-01

    Purpose – The purpose of this paper is to investigate routes towards supplier and production network internationalisation. Design/methodology/approach – Multiple case-study analysis has been applied to a sample of 11 Italian footwear and apparel companies with headquarters located in the North-east of Italy. Within and cross-case analyses illustrate and compare how these firms relocated one or more segments of their supplier and production networks to Romania. Findings – The...

  15. Catalytic routes from biomass to fuels

    DEFF Research Database (Denmark)

    Riisager, Anders

    2014-01-01

    chain unaffected. This presentation will survey the status of biofuels production from different sources, and discuss the sustainability of making transportation fuels from biomass. Furthermore, recently developed chemocatalytic technologies that allow efficient conversion of lignocellulosic biomass...... the chemical industry to find new feasible chemocatalytic routes to convert the components of lignocellulosic plant biomass (green biomass) as well as aquatic biomass (blue biomass) into potential platform chemicals that can replace the fossil based chemicals in order to leave the chemical supply and value...

  16. Route survey periodicity for mine warfare

    OpenAIRE

    Coke, Hartwell F.

    2009-01-01

    Approved for public release, distribution unlimited One of the Navy's most long standing challenges has been conquering the mine warfare threat. As mines and mine warfare techniques evolve and become more sophisticated, so does the United States' ability to counter the threat. The United States newest technique for countering a potential mined harbor, or route, is a process known as "change detection." This concept uses previous side scan sonar images of the area prior to a mining event an...

  17. PROPOSAL OF ALGORITHM FOR ROUTE OPTIMIZATION

    OpenAIRE

    Robert Ramon de Carvalho Sousa; Abimael de Jesus Barros Costa; Eliezé Bulhões de Carvalho; Adriano de Carvalho Paranaíba; Daylyne Maerla Gomes Lima Sandoval

    2016-01-01

    This article uses “Six Sigma” methodology for the elaboration of an algorithm for routing problems which is able to obtain more efficient results than those from Clarke and Wright´s (CW) algorithm (1964) in situations of random increase of product delivery demands, facing the incapability of service level increase . In some situations, the algorithm proposed obtained more efficient results than the CW algorithm. The key factor was a reduction in the number of mistakes (on...

  18. Vehicle Routing Problems for Drone Delivery

    OpenAIRE

    Dorling, Kevin; Heinrichs, Jordan; Messier, Geoffrey G.; Magierowski, Sebastian

    2016-01-01

    Unmanned aerial vehicles, or drones, have the potential to significantly reduce the cost and time of making last-mile deliveries and responding to emergencies. Despite this potential, little work has gone into developing vehicle routing problems (VRPs) specifically for drone delivery scenarios. Existing VRPs are insufficient for planning drone deliveries: either multiple trips to the depot are not permitted, leading to solutions with excess drones, or the effect of battery and payload weight ...

  19. Waste Collection Vehicle Routing Problem: Literature Review

    OpenAIRE

    Hui Han; Eva Ponce Cueto

    2015-01-01

    Waste generation is an issue which has caused wide public concern in modern societies, not only for the quantitative rise of the amount of waste generated, but also for the increasing complexity of some products and components. Waste collection is a highly relevant activity in the reverse logistics system and how to collect waste in an efficient way is an area that needs to be improved. This paper analyzes the major contribution about Waste Collection Vehicle Routing Problem (WCVRP) in litera...

  20. Locating Depots for Capacitated Vehicle Routing

    DEFF Research Database (Denmark)

    Gørtz, Inge Li; Nagarajan, Viswanath

    2011-01-01

    that all demands are satisfied and the total cost is minimized. Our main result is a constant-factor approximation algorithm for k-LocVRP. To achieve this result, we reduce k-LocVRP to the following generalization of k median, which might be of independent interest. Given a metric (V, d), bound k...... median forest, which leads to a (12+E)-approximation algorithm for k-LocVRP, for any constant E > 0. The algorithm for k median forest is t-swap local search, and we prove that it has locality gap 3 + 2 t ; this generalizes the corresponding result for k median [3]. Finally we consider the k median......We study a location-routing problem in the context of capacitated vehicle routing. The input to k-LocVRP is a set of demand locations in a metric space and a fleet of k vehicles each of capacity Q. The objective is to locate k depots, one for each vehicle, and compute routes for the vehicles so...