WorldWideScience

Sample records for derived synthesis gas

  1. Catalytic Production of Ethanol from Biomass-Derived Synthesis Gas

    Energy Technology Data Exchange (ETDEWEB)

    Trewyn, Brian G. [Colorado School of Mines, Golden, CO (United States); Smith, Ryan G. [Iowa State Univ., Ames, IA (United States)

    2016-06-01

    Heterogeneous catalysts have been developed for the conversion of biomass-derived synthetic gas (syngas) to ethanol. The objectives of this project were to develop a clean synthesis gas from biomass and develop robust catalysts with high selectivity and lifetime for C2 oxygenate production from biomass-derived syngas and surrogate syngas. During the timeframe for this project, we have made research progress on the four tasks: (1) Produce clean bio-oil generated from biomass, such as corn stover or switchgrass, by using fast pyrolysis system, (2) Produce clean, high pressure synthetic gas (syngas: carbon monoxide, CO, and hydrogen, H2) from bio-oil generated from biomass by gasification, (3) Develop and characterize mesoporous mixed oxide-supported metal catalysts for the selective production of ethanol and other alcohols, such as butanol, from synthesis gas, and (4) Design and build a laboratory scale synthesis gas to ethanol reactor system evaluation of the process. In this final report, detailed explanations of the research challenges associated with this project are given. Progress of the syngas production from various biomass feedstocks and catalyst synthesis for upgrading the syngas to C2-oxygenates is included. Reaction properties of the catalyst systems under different reaction conditions and different reactor set-ups are also presented and discussed. Specifically, the development and application of mesoporous silica and mesoporous carbon supports with rhodium nanoparticle catalysts and rhodium nanoparticle with manganese catalysts are described along with the significant material characterizations we completed. In addition to the synthesis and characterization, we described the activity and selectivity of catalysts in our micro-tubular reactor (small scale) and fixed bed reactor (larger scale). After years of hard work, we are proud of the work done on this project, and do believe that this work will provide a solid

  2. Biological upgrading of coal-derived synthesis gas: Final report

    Energy Technology Data Exchange (ETDEWEB)

    Barik, S.; Johnson, E.R.; Ko, C.W.; Clausen, E.C.; Gaddy, J.L.

    1986-10-01

    The technical feasibility of the biological conversion of coal synthesis gas to methane has been demonstrated in the University of Arkansas laboratories. Cultures of microorganisms have been developed which achieve total conversion in the water gas shift and methanation reactions in either mixed or pure cultures. These cultures carry out these conversions at ordinary temperatures and pressures, without sulfur toxicity. Several microorganisms have been identified as having commercial potential for producing methane. These include a mixed culture of unidentified bacteria; P. productus which produces acetate, a methane precursor; and Methanothrix sp., which produces methane from acetate. These cultures have been used in mixed reactors and immobilized cell reactors to achieve total CO and H/sub 2/ conversion in a retention time of less than two hours, quite good for a biological reactor. Preliminary economic projections indicate that a biological methanation plant with a size of 5 x 10/sup 10/ Btu/day can be economically attractive. 42 refs., 26 figs., 86 tabs.

  3. Impact of Contaminants Present in Coal-Biomass Derived Synthesis Gas on Water-gas Shift and Fischer-Tropsch Synthesis Catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Alptekin, Gokhan [TDA Research, Inc., Wheat Ridge, CO (United States)

    2013-02-15

    Co-gasification of biomass and coal in large-scale, Integrated Gasification Combined Cycle (IGCC) plants increases the efficiency and reduces the environmental impact of making synthesis gas ("syngas") that can be used in Coal-Biomass-to-Liquids (CBTL) processes for producing transportation fuels. However, the water-gas shift (WGS) and Fischer-Tropsch synthesis (FTS) catalysts used in these processes may be poisoned by multiple contaminants found in coal-biomass derived syngas; sulfur species, trace toxic metals, halides, nitrogen species, the vapors of alkali metals and their salts (e.g., KCl and NaCl), ammonia, and phosphorous. Thus, it is essential to develop a fundamental understanding of poisoning/inhibition mechanisms before investing in the development of any costly mitigation technologies. We therefore investigated the impact of potential contaminants (H2S, NH3, HCN, AsH3, PH3, HCl, NaCl, KCl, AS3, NH4NO3, NH4OH, KNO3, HBr, HF, and HNO3) on the performance and lifetime of commercially available and generic (prepared in-house) WGS and FT catalysts.

  4. The economic production of alcohol fuels from coal-derived synthesis gas

    Energy Technology Data Exchange (ETDEWEB)

    Kugler, E.L.; Dadyburjor, D.B.; Yang, R.Y.K. [West Virginia Univ., Morgantown, WV (United States)] [and others

    1995-12-31

    The objectives of this project are to discover, (1) study and evaluate novel heterogeneous catalytic systems for the production of oxygenated fuel enhancers from synthesis gas. Specifically, alternative methods of preparing catalysts are to be investigated, and novel catalysts, including sulfur-tolerant ones, are to be pursued. (Task 1); (2) explore, analytically and on the bench scale, novel reactor and process concepts for use in converting syngas to liquid fuel products. (Task 1); (3) simulate by computer the most energy efficient and economically efficient process for converting coal to energy, with primary focus on converting syngas to fuel alcohols. (Task 2); (4) develop on the bench scale the best holistic combination of chemistry, catalyst, reactor and total process configuration integrated with the overall coal conversion process to achieve economic optimization for the conversion of syngas to liquid products within the framework of achieving the maximum cost effective transformation of coal to energy equivalents. (Tasks 1 and 2); and (5) evaluate the combustion, emission and performance characteristics of fuel alcohols and blends of alcohols with petroleum-based fuels. (Task 2)

  5. Continuous gas/liquid–liquid/liquid flow synthesis of 4-fluoropyrazole derivatives by selective direct fluorination

    Directory of Open Access Journals (Sweden)

    Jessica R. Breen

    2011-08-01

    Full Text Available 4-Fluoropyrazole systems may be prepared by a single, sequential telescoped two-step continuous gas/liquid–liquid/liquid flow process from diketone, fluorine gas and hydrazine starting materials.

  6. Processes in petroleum chemistry. Technical and economical characteristics Vol. 1. Synthesis gas and derivatives. Main hydrocarbon intermediaries (2 ed. )

    Energy Technology Data Exchange (ETDEWEB)

    Chauvel, A.; Lefebvre, G.; Castex, L.

    1985-01-01

    The aim of this book is to give rudiments for a preliminary study to outline petrochemical operation and cost estimation. Basic operations are examined: Steam reforming or partial oxidation, steam or thermal cracking and catalytic reforming. The main topics examined include: hydrogen purification, hydrogen fabrication from hydrocarbons, carbonaceous materials or water, production of carbon monoxide, ammoniac synthesis methanol synthesis from synthesis gas, preparation of formol, urea, acetylene and monomers for the preparation of plastics.

  7. Gas Phase Nanoparticle Synthesis

    Science.gov (United States)

    Granqvist, Claes; Kish, Laszlo; Marlow, William

    This book deals with gas-phase nanoparticle synthesis and is intended for researchers and research students in nanomaterials science and engineering, condensed matter physics and chemistry, and aerosol science. Gas-phase nanoparticle synthesis is instrumental to nanotechnology - a field in current focus that raises hopes for environmentally benign, resource-lean manufacturing. Nanoparticles can be produced by many physical, chemical, and even biological routes. Gas-phase synthesis is particularly interesting since one can achieve accurate manufacturing control and hence industrial viability.

  8. DEVELOPMENT OF NOVEL CERAMIC NANOFILM-FIBER INTEGRATED OPTICAL SENSORS FOR RAPID DETECTION OF COAL DERIVED SYNTHESIS GAS

    Energy Technology Data Exchange (ETDEWEB)

    Junhang Dong; Hai Xiao; Xiling Tang; Hongmin Jiang; Kurtis Remmel; Amardeep Kaur

    2012-09-30

    The overall goal of this project is to conduct fundamental studies on advanced ceramic materials and fiber optic devices for developing new types of high temperature (>500{degree}C) fiber optic chemical sensors (FOCS) for monitoring fossil (mainly coal) and biomass derived gases in power plants. The primary technical objective is to investigate and demonstrate the nanocrystalline doped-ceramic thin film enabled FOCS that possess desired stability, sensitivity and selectivity for in-situ, rapid gas detection in the syngas streams from gasification and combustion flue gases. This report summarizes research works of two integrated parts: (1) development of metal oxide solid thin films as sensing materials for detection and measurement of important gas components relevant to the coal- and biomass-derived syngas and combustion gas streams at high temperatures; and (2) development of fiber optic devices that are potentially useful for constructing FOCS in combination with the solid oxide thin films identified in this program.

  9. The economical production of alcohol fuels from coal-derived synthesis gas. Quarterly technical progress report Number 8, 1 July, 1993--30 September, 1993

    Energy Technology Data Exchange (ETDEWEB)

    1993-10-01

    Task 1, the preparation of catalyst materials, is proceeding actively. At WVU, catalysts based on Mo are being prepared using a variety of approaches to alter the oxidation state and environment of the Mo. At UCC and P, copper-based zinc chromite spinel catalysts will be prepared and tested. The modeling of the alcohol-synthesis reaction in a membrane reactor is proceeding actively. Under standard conditions, pressure drop in the membrane reactor has been shown to be negligible. In Task 2, base case designs had previously been completed with a Texaco gasifier. Now, similar designs have been completed using the Shell gasifier. A comparison of the payback periods or production cost of these plants shows significant differences among the base cases. However, a natural gas only design, prepared for comparison purposes, gives a lower payback period or production cost. Since the alcohol synthesis portion of the above processes is the same, the best way to make coal-derived higher alcohols more attractive economically than natural gas-derived higher alcohols is by making coal-derived syngas less expensive than natural gas-derived syngas. The maximum economically feasible capacity for a higher alcohol plant from coal-derived syngas appears to be 32 MM bbl/yr. This is based on consideration of regional coal supply in the eastern US, coal transportation, and regional product demand. The benefits of economics of scale are illustrated for the base case designs. A value for higher alcohol blends has been determined by appropriate combination of RVP, octane number, and oxygen content, using MTBE as a reference. This analysis suggests that the high RVP of methanol in combination with its higher water solubility make higher alcohols more valuable than methanol.

  10. Quinazoline derivatives: synthesis and bioactivities

    OpenAIRE

    Wang, Dan; Gao, Feng

    2013-01-01

    Owing to the significant biological activities, quinazoline derivatives have drawn more and more attention in the synthesis and bioactivities research. This review summarizes the recent advances in the synthesis and biological activities investigations of quinazoline derivatives. According to the main method the authors adopted in their research design, those synthetic methods were divided into five main classifications, including Aza-reaction, Microwave-assisted reaction, Metal-mediated reac...

  11. Synthesis of 2-phosphaadamantane derivatives

    International Nuclear Information System (INIS)

    Zemlyanoi, V.N.; Aleksandrov, A.M.; Kukhar', V.P.

    1986-01-01

    The authors describe the synthesis and properties of 2-phosphadamantane derivatives. For the synthesis of 2-phosphaadamantane derivatives they decided to use the methodology of the synthesis of 2-thiaadamantane. The IR spectra were determined on CHCl 3 solutions with a Specord 711R spectrometer, the PMR spectra were determined on Tesla BS-467 (60 MHz) and Bruker WP-200 (200 MHz) spectrometers, external standard hexamethyldisiloxane, the 31 P NMR spectra were determined on Tesla BS-487 C (30 MHz) and Bruker WP-200 (81 MHz) spectrometers, external standard 85% phosphoric acid, and the mass spectra were determined on an MS-1302 spectrometer

  12. Assesment of the energy quality of the synthesis gas produced from biomass derived fuels conversion: Part I: Liquid Fuels, Ethanol

    International Nuclear Information System (INIS)

    Arteaga Perez, Luis E; Casas, Yannay; Peralta, Luis M; Granda, Daikenel; Prieto, Julio O

    2011-01-01

    The use of biofuels plays an important role to increase the efficiency and energetic safety of the energy processes in the world. The main goal of the present research is to study from the thermodynamics and kinetics the effect of the operational variables on the thermo-conversion processes of biomass derived fuels focused on ethanol reforming. Several models are developed to assess the technological proposals. The minimization of Gibbs free energy is the criterion applied to evaluate the performance of the different alternatives considering the equilibrium constraints. All the models where validated on an experimental data base. The gas composition, HHV and the ratio H2/CO are used as measures for the process efficiency. The operational parameters are studied in a wide range (reactants molar ratio, temperature and oxygen/fuel ratio). (author)

  13. Alternative Fuels and Chemicals from Synthesis Gas

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    1998-12-02

    The overall objectives of this program are to investigate potential technologies for the conversion of synthesis gas to oxygenated and hydrocarbon fuels and industrial chemicals, and to demonstrate the most promising technologies at DOE's LaPorte, Texas, Slurry Phase Alternative Fuels Development Unit (AFDU). The program will involve a continuation of the work performed under the Alternative Fuels from Coal-Derived Synthesis Gas Program and will draw upon information and technologies generated in parallel current and future DOE-funded contracts.

  14. Alternative fuels and chemicals from synthesis gas

    Energy Technology Data Exchange (ETDEWEB)

    Unknown

    1998-08-01

    The overall objectives of this program are to investigate potential technologies for the conversion of synthesis gas to oxygenated and hydrocarbon fuels and industrial chemicals, and to demonstrate the most promising technologies at DOE's LaPorte, Texas, Slurry Phase Alternative Fuels Development Unit (AFDU). The program will involve a continuation of the work performed under the Alternative Fuels from Coal-Derived Synthesis Gas Program and will draw upon information and technologies generated in parallel current and future DOE-funded contracts.

  15. ALTERNATIVE FUELS AND CHEMICALS FROM SYNTHESIS GAS

    Energy Technology Data Exchange (ETDEWEB)

    Unknown

    1999-01-01

    The overall objectives of this program are to investigate potential technologies for the conversion of synthesis gas to oxygenated and hydrocarbon fuels and industrial chemicals, and to demonstrate the most promising technologies at DOE's LaPorte, Texas, Slurry Phase Alternative Fuels Development Unit (AFDU). The program will involve a continuation of the work performed under the Alternative Fuels from Coal-Derived Synthesis Gas Program and will draw upon information and technologies generated in parallel current and future DOE-funded contracts.

  16. Alternative Fuels and Chemicals From Synthesis Gas

    Energy Technology Data Exchange (ETDEWEB)

    none

    1998-07-01

    The overall objectives of this program are to investigate potential technologies for the conversion of synthesis gas to oxygenated and hydrocarbon fuels and industrial chemicals, and to demonstrate the most promising technologies at DOE's LaPorte, Texas, Slurry Phase Alternative Fuels Development Unit (AFDU). The program will involve a continuation of the work performed under the Alternative Fuels from Coal-Derived Synthesis Gas Program and will draw upon information and technologies generated in parallel current and future DOE-funded contracts.

  17. Design and Synthesis of Polyimides Based on Carbocyclic Pseudo-Tröger’s Base-Derived Dianhydrides for Membrane Gas Separation Applications

    KAUST Repository

    Ma, Xiaohua

    2017-07-24

    Two novel carbocyclic pseudo-Tröger’s base-derived dianhydrides, 5,6,11,12-tetrahydro-5,11-methanodibenzo[a,e][8]annulene-2,3,8,9-tetracarboxylic anhydride (CTB1) and its dione-substituted analogue 6,12-dioxo-5,6,11,12-tetrahydro-5,11-methanodibenzo[a,e][8]annulene-2,3,8,9-tetracarboxylic dianhydride (CTB2), were made and used for the synthesis of soluble polyimides of intrinsic microporosity with 3,3′-dimethylnaphthidine (DMN). The polyimides CTB1-DMN and CTB2-DMN exhibited excellent thermal stability of ∼500 °C and high BET surface areas of 580 and 469 m2 g–1, respectively. A freshly made dione-substituted CTB2-DMN membrane demonstrated promising gas separation performance with O2 permeability of 206 barrer and O2/N2 selectivity of 5.2. A higher O2 permeability of 320 barrer and lower O2/N2 selectivity of 4.2 were observed for a fresh CTB1-DMN film due to its higher surface area and less tightly packed structure as indicated by weaker charge-transfer complex interactions. Physical aging over 60 days resulted in reduction in gas permeability and moderately enhanced selectivity. CTB2-DMN exhibited notable performance with gas permeation data located between the 2008 and 2015 permeability/selectivity upper bounds for O2/N2 and H2/CH4.

  18. The economical production of alcohol fuels from coal-derived synthesis gas. Quarterly technical progress report No. 4, July 1, 1992--September 30, 1992

    Energy Technology Data Exchange (ETDEWEB)

    1993-10-01

    A base case flow sheet for the production of higher alcohols from coal derived synthesis gas has been completed, including an economic analysis. The details of the flow sheet and economics are in Appendix 1. The pay back period for the capital investment for the plant has been calculated as a function of the market price of the product, and this figure is also shown as Figure I in Appendix 1. The estimated installed cost is almost $500 MM, and the estimated annual operating cost is $64 MM. At a price in the vicinity of $1.00/gal for the alcohol product, the pay back period for construction of the plant is four years. These values should be considered preliminary, since many of the capital costs were obtained from other paper studies sponsored by DOE and TVA and very few values could be found from actual plants which were built. This issue is currently being addressed. The most expensive capital costs were found to be the gasifier, the cryogenic air separation plant, the steam/power generation plant and the acid gas/sulfur removal processes taken as a whole. It is planned to focus attention on alternatives to the base case. The problem is that it is less expensive to make syngas from natural gas. Therefore, it is essential to reduce the cost of syngas from coal. This is where the energy park concept becomes important. In order for this process to be economical (at current market and political conditions) a method must be found to reduce the cost of syngas manufacture either by producing energy or by-products. Energy is produced in the base case, but the amount and method has not been optimized. The economic arguments for this concept are detailed in Appendix 2.

  19. Development of Ni-Based Catalysts Derived from Hydrotalcite-Like Compounds Precursors for Synthesis Gas Production via Methane or Ethanol Reforming

    OpenAIRE

    Ya-Li Du; Xu Wu; Qiang Cheng; Yan-Li Huang; Wei Huang

    2017-01-01

    As a favorably clean fuel, syngas (synthesis gas) production has been the focus of concern in past decades. Substantial literatures reported the syngas production by various catalytic reforming reactions particularly in methane or ethanol reforming. Among the developed catalysts in these reforming processes, Ni-based catalysts from hydrotalcite-like compounds (HTLcs) precursors have drawn considerable attention for their preferable structural traits. This review covers the recent literature r...

  20. SYNTHESIS OF METHACRYLATES FROM COAL-DERIVED SYNGAS

    Energy Technology Data Exchange (ETDEWEB)

    Jang, B.W.L.; Spivey, J.J.; Gogate, M.R.; Zoeller, J.R.; Colberg, R.D.; Choi, G.N.

    1999-12-01

    Research Triangle Institute (RTI), Eastman Chemical Company, and Bechtel have developed a novel process for synthesis of methyl methacrylate (MMA) from coal-derived syngas, under a contract from the US Department of Energy/Fossil Energy Technology Center (DOE/FETC). This project has resulted in five US patents (four already published and one pending publication). It has served as the basis for the technical and economic assessment of the production of this high-volume intermediate from coal-derived synthesis gas. The three-step process consists of the synthesis of a propionate from ethylene carbonylation using coal-derived CO, condensation of the propionate with formaldehyde to form methacrylic acid (MAA); and esterification of MAA with methanol to yield MMA. The first two steps, propionate synthesis and condensation catalysis, are the key technical challenges and the focus of the research presented here.

  1. Preliminary Screening -- Technical and Economic Assessment of Synthesis Gas to Fuels and Chemicals with Emphasis on the Potential for Biomass-Derived Syngas

    Energy Technology Data Exchange (ETDEWEB)

    Spath, P. L.; Dayton, D. C.

    2003-12-01

    In principle, syngas (primarily consisting of CO and H2) can be produced from any hydrocarbon feedstock, including: natural gas, naphtha, residual oil, petroleum coke, coal, and biomass. The lowest cost routes for syngas production, however, are based on natural gas, the cheapest option being remote or stranded reserves. Economic considerations dictate that the current production of liquid fuels from syngas translates into the use of natural gas as the hydrocarbon source. Nevertheless, the syngas production operation in a gas-to-liquids plant amounts to greater than half of the capital cost of the plant. The choice of technology for syngas production also depends on the scale of the synthesis operation. Syngas production from solid fuels can require an even greater capital investment with the addition of feedstock handling and more complex syngas purification operations. The greatest impact on improving the economics of gas-to liquids plants is through (1) decreasing capital costs associated with syngas production and (2) improving the thermal efficiency with better heat integration and utilization. Improved thermal efficiency can be obtained by combining the gas-to-liquids plant with a power generation plant to take advantage of the availability of low-pressure steam. The extensive research and development efforts devoted to syngas conversion to fuels and chemicals are documented in a vast amount of literature that tracks the scientific and technological advancements in syngas chemistry. The purpose of this report is to review the many syngas to products processes and summarize the salient points regarding the technology status and description, chemistry, catalysts, reactors, gas cleanliness requirements, process and environmental performances, and economics. Table 1 lists the products examined in this study and gives some facts about the technology as well as advantages and disadvantages. Table 2 summarizes the catalysts, process conditions, conversions, and

  2. Synthesis and effect of physical aging on gas transport properties of a microporous polyimide derived from a novel spirobifluorene-based dianhydride

    KAUST Repository

    Ma, Xiaohua

    2015-02-17

    A novel generic method is reported for the synthesis of a spirobifluorene-based dianhydride (SBFDA). An intrinsically microporous polyimide was obtained by polycondensation reaction with 3,3′-dimethylnaphthidine (DMN). The corresponding polymer (SBFDA-DMN) exhibited good solubility, excellent thermal stability, as well as significant microporosity with high BET surface area of 686 m2/g. The O2 permeability of a methanol-treated and air-dried membrane was 1193 Barrer with a moderate O2/N2 selectivity of 3.2. The post-treatment history and aging conditions had great effects on the membrane performance. A significant drop in permeability coupled with an increase in selectivity was observed after long-term aging. After storage of 200 days, the gas separation properties of SBFDA-DMN were located slightly above the latest Robeson upper bounds for several gas pairs such as O2/N2 and H2/N2.

  3. Synthesis and effect of physical aging on gas transport properties of a microporous polyimide derived from a novel spirobifluorene-based dianhydride

    KAUST Repository

    Ma, Xiaohua; Ghanem, Bader; Salinas, Octavio; Litwiller, Eric; Pinnau, Ingo

    2015-01-01

    A novel generic method is reported for the synthesis of a spirobifluorene-based dianhydride (SBFDA). An intrinsically microporous polyimide was obtained by polycondensation reaction with 3,3′-dimethylnaphthidine (DMN). The corresponding polymer (SBFDA-DMN) exhibited good solubility, excellent thermal stability, as well as significant microporosity with high BET surface area of 686 m2/g. The O2 permeability of a methanol-treated and air-dried membrane was 1193 Barrer with a moderate O2/N2 selectivity of 3.2. The post-treatment history and aging conditions had great effects on the membrane performance. A significant drop in permeability coupled with an increase in selectivity was observed after long-term aging. After storage of 200 days, the gas separation properties of SBFDA-DMN were located slightly above the latest Robeson upper bounds for several gas pairs such as O2/N2 and H2/N2.

  4. Derivatives of 16alpha-hydroxy-dehydroepiandrosterone with an additional 7-oxo or 7-hydroxy substituent: synthesis and gas chromatography/mass spectrometry analysis.

    Science.gov (United States)

    Pouzar, Vladimír; Cerný, Ivan; Hill, Martin; Bicíková, Marie; Hampl, Richard

    2005-10-01

    Derivatives of 16alpha-hydroxy-dehydroepiandrosterone, which have an additional oxygen substituent at position 7 (oxo or hydroxy group), were synthesized. Firstly, 17,17-dimethoxyandrost-5-ene-3beta,16alpha-diyl diacetate was prepared and then oxidized with a complex of chromium(VI) oxide and 2,5-dimethylpyrazole to the respective 7-oxo derivative. This key intermediate was both deprotected or reduced by l-Selectride or sodium borohydride in the presence of cerium(III) chloride and then deprotected to give 7-oxo, 7alpha-hydroxy and 7beta-hydroxy derivatives of 16alpha-hydroxy-dehydroepiandrosterone. The target compounds were characterized by (1)H and (13)C NMR spectra and in the form of O-methyloxime-trimethylsilyl derivatives, by gas chromatography/mass spectrometry methods.

  5. Novel 6FDA-based polyimides derived from sterically hindered Tröger's base diamines: Synthesis and gas permeation properties

    KAUST Repository

    Ghanem, Bader

    2016-04-30

    Two novel Tröger\\'s base-based di-o-substituted diamine monomers were synthesized and used to prepare two intrinsically microporous 6FDA-based polyimides (PIM-PI-TB-1 and PIM-PI-TB-2) with high molecular weight, high thermal stability and excellent solubility in common organic solvents. Compared to previously reported methods for preparing TB-based diamines, which are based on reduction of dimerized nitro-substituted anilines or condensation of phenylenediamine derivatives with dianhydrides, the novel protocol can be used to prepare different functionalized TB-based diamine monomers from a wide variety of aniline derivatives. PIM-PI-TB-1 (made from 6FDA and dibromo-tetramethyl-substituted TB diamine) and PIM-PI-TB-2 (made from 6FDA and tetramethyl-substituted TB diamine) are intrinsically microporous polymers with high BET surface areas of 440 m2/g and 580 m2/g, respectively. Pure-gas permeability coefficients of He, H2, N2, O2, CH4, and CO2 were measured at 35 °C and 2 bar for fresh and 180 days aged films. Both TB-based polyimides exhibited high gas permeability with moderate selectivity. The gas permeability dropped significantly coupled with a moderate increase in selectivity after long-term physical aging of 180 days.

  6. Novel 6FDA-based polyimides derived from sterically hindered Tröger's base diamines: Synthesis and gas permeation properties

    KAUST Repository

    Ghanem, Bader; Alaslai, Nasser Y.; Miao, Xiaohe; Pinnau, Ingo

    2016-01-01

    Two novel Tröger's base-based di-o-substituted diamine monomers were synthesized and used to prepare two intrinsically microporous 6FDA-based polyimides (PIM-PI-TB-1 and PIM-PI-TB-2) with high molecular weight, high thermal stability and excellent solubility in common organic solvents. Compared to previously reported methods for preparing TB-based diamines, which are based on reduction of dimerized nitro-substituted anilines or condensation of phenylenediamine derivatives with dianhydrides, the novel protocol can be used to prepare different functionalized TB-based diamine monomers from a wide variety of aniline derivatives. PIM-PI-TB-1 (made from 6FDA and dibromo-tetramethyl-substituted TB diamine) and PIM-PI-TB-2 (made from 6FDA and tetramethyl-substituted TB diamine) are intrinsically microporous polymers with high BET surface areas of 440 m2/g and 580 m2/g, respectively. Pure-gas permeability coefficients of He, H2, N2, O2, CH4, and CO2 were measured at 35 °C and 2 bar for fresh and 180 days aged films. Both TB-based polyimides exhibited high gas permeability with moderate selectivity. The gas permeability dropped significantly coupled with a moderate increase in selectivity after long-term physical aging of 180 days.

  7. Synthesis, characterization and performance of NiMo catalysts supported on titania modified alumina for the hydroprocessing of different gas oils derived from Athabasca bitumen

    Energy Technology Data Exchange (ETDEWEB)

    Ferdous, D.; Bakhshi, N.N.; Dalai, A.K. [Catalysis and Chemical Reactor Engineering Laboratories, Department of Chemical Engineering, University of Saskatchewan, 57 Campus Drive, Saskatoon, Sask. (Canada); Adjaye, J. [Syncrude Canada Ltd., Edmonton Research Center, No. 9421, 17th Avenue, Edmonton, Alta. (Canada)

    2007-03-08

    In this work, a series of NiMo/Al{sub 2}O{sub 3} catalyst was prepared using different Al{sub 2}O{sub 3} supports modified by titania (0-9 wt%). All modified supports and fresh catalysts were characterized by BET surface area, pore volume and pore diameter measurement, TPR, TPD, XRD, FTIR and Raman spectroscopy analyses. The initial activity of these catalysts were tested in a trickle-bed reactor using three different gas oils such as light gas oil (LGO), blended gas oil (blended: 50% LGO and 50% HGO) and heavy gas oil (HGO), all derived from Athabasca bitumen. Little structural change in alumina was observed with the incorporation of titania. XRD analysis showed the well dispersion of Ni and Mo on the support. Titania in alumina increased the formation of polymolybdenum oxide on the catalyst as evident from TPR and Raman analyses. Weak-intermediate-strong acid sites on the catalyst were observed at all titania concentrations. The Lewis and Bronsted acidity on the catalyst surface increased with the increase in titania concentration from 0 to 9 wt%. Nitrogen conversion increased from 57 to 71 wt%, from 83 to 93 wt% and from 75 to 80 wt% for LGO, blended and HGO, respectively and also sulfur conversion of LGO increased from 86 to 92 wt% when titania concentration was increased from 0 to 9 wt%. For blended and HGO, sulfur conversion was in the range 96-99 wt% at all titania concentrations. (author)

  8. Development of Ni-Based Catalysts Derived from Hydrotalcite-Like Compounds Precursors for Synthesis Gas Production via Methane or Ethanol Reforming

    Directory of Open Access Journals (Sweden)

    Ya-Li Du

    2017-02-01

    Full Text Available As a favorably clean fuel, syngas (synthesis gas production has been the focus of concern in past decades. Substantial literatures reported the syngas production by various catalytic reforming reactions particularly in methane or ethanol reforming. Among the developed catalysts in these reforming processes, Ni-based catalysts from hydrotalcite-like compounds (HTLcs precursors have drawn considerable attention for their preferable structural traits. This review covers the recent literature reporting syngas production with Ni-based catalysts from HTLc precursors via methane or ethanol reforming. The discussion was initiated with catalyst preparation (including conventional and novel means, followed by subsequent thermal treatment processes, then composition design and the addition of promoters in these catalysts. As Ni-based catalysts have thermodynamic potential to deactivate because of carbon deposition or metal sintering, measures for dealing with these problems were finally summarized. To obtain optimal catalytic performances and resultantly better syngas production, based on analyzing the achievements of the references, some perspectives were finally proposed.

  9. derivatives: Synthesis and antimicrobial evaluation

    Indian Academy of Sciences (India)

    cal activity study revealed that all compounds showed promising activities and bis-(1H-2-benzopyran-1-one) derivatives (5) ...... A and Galvez J 2004 Planta Med. 70 315. 6. ... Ante N, Erik De C, Jan B and Mladen M 2011 Molecules. 16 6023.

  10. Synthesis of Lipophilic Guanine N-9 Derivatives

    DEFF Research Database (Denmark)

    Wamberg, Michael C; Pedersen, Pernille L; Löffler, Philipp M G

    2017-01-01

    the synthesis of five new guanine-N9 derivatives bearing alkyl chains with different attachment chemistries, exploiting a synthesis pathway that allows a flexible choice of hydrophobic anchor moiety. In this study, these guanine derivatives were functionalized with C10 chains for insertion into decanoic acid...... bilayer structures, in which both alkyl chain length and attachment chemistry determined their interaction with the membrane. Incubation of these guanine conjugates, as solids, with a decanoic acid vesicle suspension, showed that ether- and triazole-linked C10 anchors yielded an increased partitioning...... of the guanine derivative into the membranous phase compared to directly N-9-linked saturated alkyl anchors. Decanoic acid vesicle membranes could be loaded with up to 5.5 mol % guanine derivative, a 6-fold increase over previous limits. Thus, anchor chemistries exhibiting favorable interactions with a bilayer...

  11. Derivation of the Ideal Gas Law

    Science.gov (United States)

    Laugier, Alexander; Garai, Jozsef

    2007-01-01

    Undergraduate and graduate physics and chemistry books usually state that combining the gas laws results in the ideal gas law. Leaving the derivation to the students implies that this should be a simple task, most likely a substitution. Boyle's law, Charles's law, and the Avogadro's principle are given under certain conditions; therefore, direct…

  12. Preliminary screening: Technical and economic assessment of synthesis gas to fuels and chemicals with emphasis on the potential for biomass-derived syngas

    Energy Technology Data Exchange (ETDEWEB)

    Spath, P. L. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Dayton, D. C. [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2003-12-01

    This report reviews the many syngas to products processes and summarizes the technology status and description, chemistry, catalysts, reactors, gas cleanliness requirements, process and environmental performances, and economics.

  13. Generation of synthesis gas by partial oxidation of natural gas in a gas turbine

    NARCIS (Netherlands)

    Cornelissen, R.; Tober, E.; Kok, Jacobus B.W.; van der Meer, Theodorus H.

    2006-01-01

    The application of partial oxidation in a gas turbine (PO-GT) in the production of synthesis gas for methanol production is explored. In PO-GT, methane is compressed, preheated, partial oxidized and expanded. For the methanol synthesis a 12% gain in thermal efficiency has been calculated for the

  14. Quinoline derivative containing monomeric and polymeric metal carboxylates: Synthesis, crystal structure and gas adsorption study over a 2D layered framework

    Science.gov (United States)

    Gayen, Saikat; Saha, Debraj; Koner, Subratanath

    2018-06-01

    A new supramolecular metal-carboxylate framework [Co(mqc)2]n (1), and another monomeric compound [Zn (mqc)2(H2O)] (2) (mqcH = 4-methoxy 2-quinolinecarboxylic acid) have been synthesized solvothermally and characterized by single crystal X-ray diffraction, elemental analysis, IR spectra, UV-vis spectra, powdered X-ray diffraction (PXRD) and thermogravimetric analysis. Compound 1 is a 2D coordination polymer, extended to a 3D porous supramolecular network having void space in between 2D layers. Compound 1 exhibits gas uptake capacity of N2, H2, CO2 and CH4 like small gas molecules in which moderately high uptake of H2 and CO2 takes place among the 2D MOFs. While the Zn variety, compound 2 features a one-dimensional chain like structure through strong intermolecular hydrogen-bonding.

  15. Method and apparatus for producing synthesis gas

    Science.gov (United States)

    Hemmings, John William; Bonnell, Leo; Robinson, Earl T.

    2010-03-03

    A method and apparatus for reacting a hydrocarbon containing feed stream by steam methane reforming reactions to form a synthesis gas. The hydrocarbon containing feed is reacted within a reactor having stages in which the final stage from which a synthesis gas is discharged incorporates expensive high temperature materials such as oxide dispersed strengthened metals while upstream stages operate at a lower temperature allowing the use of more conventional high temperature alloys. Each of the reactor stages incorporate reactor elements having one or more separation zones to separate oxygen from an oxygen containing feed to support combustion of a fuel within adjacent combustion zones, thereby to generate heat to support the endothermic steam methane reforming reactions.

  16. GAS-PHASE SYNTHESIS OF PRECURSORS OF INTERSTELLAR GLYCINE: A COMPUTATIONAL STUDY OF THE REACTIONS OF ACETIC ACID WITH HYDROXYLAMINE AND ITS IONIZED AND PROTONATED DERIVATIVES

    Energy Technology Data Exchange (ETDEWEB)

    Barrientos, Carmen; Redondo, Pilar; Largo, Laura; Rayon, Victor M.; Largo, Antonio, E-mail: alargo@qf.uva.es [Departamento de Quimica Fisica y Quimica Inorganica, Facultad de Ciencias, Universidad de Valladolid, 47005 Valladolid (Spain)

    2012-04-01

    A computational study of the reactions of hydroxylamine and its ionized and protonated derivatives with acetic acid is provided. The reaction of neutral hydroxylamine with acetic acid, despite being clearly exothermic, involves a very large energy barrier. The reaction of ionized hydroxylamine with acetic acid is also clearly exothermic, but again a significant energy barrier is found (around 24 kcal mol{sup -1} at the CCSD(T) level). The reaction of the most stable protonated isomer of hydroxylamine, NH{sub 3}OH{sup +}, with acetic acid also involves a high barrier (more than 27 kcal mol{sup -1} at the CCSD(T) level). Only the higher energy isomer, NH{sub 2}OH{sup +}{sub 2}, leads to a sensibly lower energy barrier (about 2.3 kcal mol{sup -1} at the CCSD(T) level). Nevertheless, an estimate of the reaction coefficient at low temperatures such as those reigning in the interstellar medium gives very low values. Therefore, it seems that precursors of interstellar glycine could not be efficiently produced from the reactions of hydroxylamine-derived ions with acetic acid.

  17. GAS-PHASE SYNTHESIS OF PRECURSORS OF INTERSTELLAR GLYCINE: A COMPUTATIONAL STUDY OF THE REACTIONS OF ACETIC ACID WITH HYDROXYLAMINE AND ITS IONIZED AND PROTONATED DERIVATIVES

    International Nuclear Information System (INIS)

    Barrientos, Carmen; Redondo, Pilar; Largo, Laura; Rayón, Víctor M.; Largo, Antonio

    2012-01-01

    A computational study of the reactions of hydroxylamine and its ionized and protonated derivatives with acetic acid is provided. The reaction of neutral hydroxylamine with acetic acid, despite being clearly exothermic, involves a very large energy barrier. The reaction of ionized hydroxylamine with acetic acid is also clearly exothermic, but again a significant energy barrier is found (around 24 kcal mol –1 at the CCSD(T) level). The reaction of the most stable protonated isomer of hydroxylamine, NH 3 OH + , with acetic acid also involves a high barrier (more than 27 kcal mol –1 at the CCSD(T) level). Only the higher energy isomer, NH 2 OH + 2 , leads to a sensibly lower energy barrier (about 2.3 kcal mol –1 at the CCSD(T) level). Nevertheless, an estimate of the reaction coefficient at low temperatures such as those reigning in the interstellar medium gives very low values. Therefore, it seems that precursors of interstellar glycine could not be efficiently produced from the reactions of hydroxylamine-derived ions with acetic acid.

  18. Synthesis of acetylenic derivatives of hydroxynaphthoquinone

    International Nuclear Information System (INIS)

    Sanchez Kopper, Andres

    2010-01-01

    The acetylene derivatives synthesis 2-hydroxy-1 ,4-naphthoquinones was studied using different reaction conditions: coupling with copper and silver acetylides, Sonogashira reaction with and without CU (I) as cocatalyst. The reaction conditions are optimized for coupling of iodine lawson and ylide phenyl lawsone of iodine with various terminal acetylenes: phenyl acetylene, propargyl alcohol, 1-heptin and 2-methyl-3-butyne-2-ol. Also, reactants such as bromides of hidroxinaphthoquinones were used with protecting groups such as acetate, methoxy, phenyloxy, benzyloxy and tricloroetoxy. The synthesis of 2-hydroxy-3-(3-hydroxy-3-ynyl-1-methylbutane)-1,4-naphthoquinone, 2-methoxy-3-(2-phenylethynyl) -1,4-naphthoquinone and 2-(2-phenylethynyl)-3-(2,2,2-tricloroetoxy)-1,4-naphthoquinone was performed with rates of return of 22%, 57% and 67% respectively. The reaction of the yodolawsona was obtained with 3-chloro-3-methyl-1-butyne in the presence of CuI, CsI and Cs 2 Co 3 obtaining the enol ether: 3,3-dimethyl-2-methyl-2 ,3-dihydronaphto [2 ,3-b]furan-4,9-dione (dehydro-α-dunion), with a rate of return of 58%. This enol ether was used as a reactant for the formation, through a regioselective hydrogenation with PtO 2 /t-butanol of α-dunion with a yield of 50%. Furthermore, by acid hydrolysis with H 2 SO 4 has been possible to obtain a percentage yield of 75% streptocarpone. Both, α-dunion and streptocarpone, natural products extracted from Streptocarpus dunni shrub, with antiparasitic activity, and which so far had not presented an efficient synthesis. A mechanism is proposed for the reaction of formation of the enol ether where it is presumed the presence of a zwitterion-vinyl carbene as key intermediate of the reaction. All products were characterized by spectroscopy 1 H and 13 C-NMR, UV-Vis and IR. (author) [es

  19. Sustainable synthesis gas from biomass. A bridge to a sustainable supply of energy and resources

    International Nuclear Information System (INIS)

    Den Uil, H.; Van Ree, R.; Van der Drift, A.; Boerrigter, H.

    2004-04-01

    . However, the electricity consumption of size reduction of the feedstock prior to gasification is a bottleneck. When the electricity consumption is too high, conversion of biomass into an intermediate product will be required , using techniques as torrefaction, flash pyrolysis or low temperature gasification.. Apart from the large-scale processes, a number of processes have been/developed and are still under development for small scale. Contaminants present in the gas produced by gasification must be removed to very low levels to protect downstream equipment. By a combination of scrubbers and guard beds the required levels can be obtained. Once cleaned, the gas composition must be modified in order to meet the specifications of downstream processes using existing commercial processes. The cost of synthesis gas production from imported biomass has been analysed. For biomass imported from the Baltic states the cost of synthesis gas will be about 10 euro/GJ. About 55% of the costs originate from biomass, about 25% from transportation, storage and transshipment and only 20% from synthesis gas production. Use of the synthesis gas for the production of Fischer-Tropsch diesel will give a product price of 0.44 euro/litre, about twice the cost of fossil diesel. A significant increase in crude oil prices or tax exemptions are required to make products out of renewable synthesis gas competitive with fossil fuel derived products [nl

  20. Synthesis of New Imidazolidine and Tetrahydropyrimidine Derivatives

    Directory of Open Access Journals (Sweden)

    Hamid Beyzaei

    2014-01-01

    Full Text Available Synthesis of new imidazolidine and tetrahydropyrimidine derivatives 3a, b and 4a–c as cyclic 1,3-diamines under two reaction conditions (A and B is described. Under reaction conditions-A, a suspension of (E-2-cyano-2-(oxazolidin-2-ylideneethanethioamide 1 (1 eq. and diaminoalkanes 2a–e (2 eq. in absolute ethanol is heated under reflux for 16–22 h to afford 3a, b and 4a–c. Alternatively, under reaction conditions-B, a solution of thioamide 1 (1 eq. in diaminoalkanes 2a–e (3 eq. is stirred under solvent-free conditions at room temperature for 3 days to give desired products. Reaction conditions-A for having higher yields, shorter reaction times, and required less diamines is more effective than reaction conditions-B. Oxazolidine ring opening is observed by reacting compound 1 with all of the diamines 2a–e, but the thioamide group only reacts with nonbulky diamines 2a, b. The chemical structures of novel compounds were confirmed by 1H NMR, 13C NMR, elemental analysis, and FT-IR spectrometry.

  1. Internal Combustion Engine Powered by Synthesis Gas from Pyrolysed Plastics

    Directory of Open Access Journals (Sweden)

    Chríbik Andrej

    2016-07-01

    Full Text Available The article discusses the application of synthesis gas from pyrolysis of plastics in petrol engine. The appropriate experimental measurements were performed on a combustion engine LGW 702 designated for micro-cogeneration unit. The power parameters, economic parameters in term of brake specific fuel consumption, and internal parameters of the engine were compared to the engine running on the reference fuel - natural gas and synthesis gas. Burning synthesis gas leads to decreased performance by about 5% and to increased mass hourly consumption by 120 %. In terms of burning, synthesis gas has similar properties as natural gas. Compared with [5] a more detailed study has been prepared on the effects of angle of spark advance on the engine torque, giving more detailed assessment of engine cycle variability and considering specification of start and end of combustion in the logarithm p-V diagram.

  2. Synthesis of rearranged unsaturated drimane derivatives

    Directory of Open Access Journals (Sweden)

    Miranda Domingos S. de

    2001-01-01

    Full Text Available A full account to the preparation and application of three appropriately substituted vinylcyclohexenes (2,2-dimethyl-3-vinylcyclohex-3-en-1-ol, 2,2-dimethyl-3-vinylcyclohex-3-en-1-one and 3,3-dimethyl-2-vinylcyclohexene in thermal Diels-Alder reactions with alpha,beta-unsaturated esters (methyl tiglate and methyl angelate is given. This approach delivered the racemic synthesis of ten octalin derivatives bearing a rearranged drimane skeleton (4 diastereomers of 1-methoxycarbonyl-6-hydroxy-1,2,5,5-tetramethyl-1,2,3,5,6,7, 8,8a-octahydronaphthalene; 1-methoxycarbonyl-6-oxo-1,2,5,5-tetramethyl-1,2,3,4,5,6,7,8-octahydronaphthalene; 2-methoxycarbonyl-6-oxo-1,2,5,5-tetramethyl-1,2,3,5,6,7,8,8a-octahydronaphthalene; 3 diastereomers of 1-methoxycarbonyl-1,2,5,5-tetramethyl-1,2,3,5,6,7,8,8a-octahydronaphthalene and 2-methoxycarbonyl-1,2,5,5-tetramethyl-1,2,3,5,6,7,8,8a-octahydronaphthalene . Central synthetic features included preparation of enoltriflates by Stang's protocol and the successful palladium-catalyzed cross-coupling reaction (Stille reaction of the triflate with the tri-n-butylvinylstannane. The octalins relative stereochemistry was unequivocally ascertained by spectroscopic methods and/or X-ray crystallography and these data now stand as useful tools to support the correct assignment of related natural products usually isolated in minute amounts.

  3. Alternative fuels and chemicals from synthesis gas

    Energy Technology Data Exchange (ETDEWEB)

    Unknown

    1998-12-01

    A DOE/PETC funded study was conducted to examine the use of a liquid phase mixed alcohol synthesis (LPMAS) plant to produce gasoline blending ethers. The LPMAS plant was integrated into three utilization scenarios: a coal fed IGCC power plant, a petroleum refinery using coke as a gasification feedstock, and a standalone natural gas fed partial oxidation plant. The objective of the study was to establish targets for the development of catalysts for the LPMAS reaction. In the IGCC scenario, syngas conversions need only be moderate because unconverted syngas is utilized by the combined cycle system. A once through LPMAS plant achieving syngas conversions in the range of 38--49% was found to be suitable. At a gas hourly space velocity of 5,000 sL/Kg-hr and a methanol:isobutanol selectivity ratio of 1.03, the target catalyst productivity ranges from 370 to 460 g iBuOH/Kg-hr. In the petroleum refinery scenario, high conversions ({approximately}95%) are required to avoid overloading the refinery fuel system with low Btu content unconverted syngas. To achieve these high conversions with the low H{sub 2}/CO ratio syngas, a recycle system was required (because of the limit imposed by methanol equilibrium), steam was injected into the LPMAS reactor, and CO{sub 2} was removed from the recycle loop. At the most economical recycle ratio, the target catalyst productivity is 265 g iBuOH/Kg-hr. In the standalone LPMAS scenario, essentially complete conversions are required to achieve a fuel balanced plant. At the most economical recycle ratio, the target catalyst productivity is 285 g iBuOH/Kg-hr. The economics of this scenario are highly dependent on the cost of the natural gas feedstock and the location of the plant. For all three case scenarios, the economics of a LPMAS plant is marginal at current ether market prices. Large improvements over demonstrated catalyst productivity and alcohol selectivity are required.

  4. SHORT COMMUNICATION SYNTHESIS OF AZIDO DERIVATIVES ...

    African Journals Online (AJOL)

    Preferred Customer

    Department of Chemistry & Chemical Technology, Faculty of Science, Engineering & ... substitution reactions with various nucleophiles, including azides and ... readily available substrate for the synthesis of an array of chemical compounds.

  5. Solventless Synthesis of Quinoline Derivatives: Acceleration of ...

    African Journals Online (AJOL)

    NICO

    bKermanshah Oil Refining Company, Kermanshah, Iran. Received 25 October ... formation of polymers that combine enhanced electronic, opto- electronic, or ..... 960/85. Long reaction time, difficulties in the catalyst synthesis and. 41 recovery.

  6. Synthesis and electronic aspects of tetrahydrobenzothienopyrimidine derivatives

    Science.gov (United States)

    Gajda, Katarzyna; Astakhina, Valeriia; Ejsmont, Krzysztof; Kolomeitsev, Dmytro; Kovalenko, Sergiy; Zarychta, Bartosz

    2015-03-01

    The chemistry of thiophenes, pyrimidines, triazolopyrimidines and benzothiophenes has drawn much attention because of their biological activities. Their interesting properties are connected with their complex π-electron delocalisation effects. Herein the synthesis, crystal and molecular structures at 100 K and DFT calculated structures of three tetrahydrobenzothienopyrimidine derivatives are reported i.e. 4-hydrazino-5,6,7,8-tetrahydro[1]benzothieno[2,3-d]pyrimidine which was a substrate for 2-phenyl-8,9,10,11-tetrahydro[1]benzothieno[3,2-e][1,2,4]triazolo[1,5-c]pyrimidine and 3-methyl-9,10,11,12-tetrahydro-2H-[1]benzothieno[2‧,3‧:4,5]pyrimido[1,6-b][1,2,4]triazin-2-one. Moreover the influence of the substituents, polycyclic structure and crystal packing and on the aromaticity of the fused heterocyclic rings have been also discussed. The 4-hydrazino-5,6,7,8-tetrahydro[1]benzothieno[2,3-d]pyrimidine is a promising substrate for a number of different reactions and discovering novel biologically active heterocycles. All three molecules are planar except of the tetrahydrobenzene part, which shows normal conformation. In crystals the molecules are connected to each other by C-H⋯N, N-H⋯N, C-H⋯S and S⋯π contacts. The geometry of common core in all structures is similar and typical for this class of compounds. The aromaticity of the fused heteroaromatic systems has been investigated by means of the HOMA indices. The discrepancy between values of HOMA for isolated monocyclic compounds and studied molecules from crystal structure shows destabilization of aromaticity when the rings are fused in a larger heterocyclic systems. The thiophene part of the molecule is far more sensitive on the influence of both mesomeric effects in polycyclic system and molecular environment in solid-state than pyrimidine ring. The presence of intermolecular interactions was confirmed by Hirshfeld area analysis.

  7. Advances in the Partial Oxidation of Methane to Synthesis Gas

    Institute of Scientific and Technical Information of China (English)

    Quanli Zhu; Xutao Zhao; Youquan Deng

    2004-01-01

    The conversion and utilization of natural gas is of significant meaning to the national economy,even to the everyday life of people. However, it has not become a popular industrial process as expected due to the technical obstacles. In the past decades, much investigation into the conversion of methane,predominant component of natural gas, has been carried out. Among the possible routes of methane conversion, the partial oxidation of methane to synthesis gas is considered as an effective and economically feasible one. In this article, a brief review of recent studies on the mechanism of the partial oxidation of methane to synthesis gas together with catalyst development is wherein presented.

  8. Proceedings of the DGMK-conference 'Synthesis gas chemistry'. Authors' manuscripts

    Energy Technology Data Exchange (ETDEWEB)

    Hoenicke, D; Kohlpaintner, C; Luecke, B; Reschetilowski, W [eds.

    2000-07-01

    The main topics of the DGMK-Conference ''Synthesis Gas Chemistry'' were: production of synthesis gas from several educts, new catalysts, Fischer-Tropsch synthesis, hydroformylation, steam reforming and carbonylation.

  9. Efficient synthesis of phosphonodepsipeptides derived from norleucine

    Czech Academy of Sciences Publication Activity Database

    Pícha, Jan; Buděšínský, Miloš; Hančlová, Ivona; Šanda, Miloslav; Fiedler, Pavel; Vaněk, Václav; Jiráček, Jiří

    2009-01-01

    Roč. 65, č. 31 (2009), s. 6090-6103 ISSN 0040-4020 R&D Projects: GA ČR GA203/06/1405; GA MŠk(CZ) LC06077 Institutional research plan: CEZ:AV0Z40550506 Keywords : phosphonate * pseudopeptide * inhibitor * synthesis * norleucine Subject RIV: CC - Organic Chemistry Impact factor: 3.219, year: 2009

  10. Method of making an aero-derivative gas turbine engine

    Science.gov (United States)

    Wiebe, David J.

    2018-02-06

    A method of making an aero-derivative gas turbine engine (100) is provided. A combustor outer casing (68) is removed from an existing aero gas turbine engine (60). An annular combustor (84) is removed from the existing aero gas turbine engine. A first row of turbine vanes (38) is removed from the existing aero gas turbine engine. A can annular combustor assembly (122) is installed within the existing aero gas turbine engine. The can annular combustor assembly is configured to accelerate and orient combustion gasses directly onto a first row of turbine blades of the existing aero gas turbine engine. A can annular combustor assembly outer casing (108) is installed to produce the aero-derivative gas turbine engine (100). The can annular combustor assembly is installed within an axial span (85) of the existing aero gas turbine engine vacated by the annular combustor and the first row of turbine vanes.

  11. Electron-beam synthesis of fuel in the gas phase

    International Nuclear Information System (INIS)

    Ponomarev, A.V.; Holodkova, E.M.; Ershov, B.G.

    2011-01-01

    Complete text of publication follows. Tendencies of world development focus attention on a vegetative biomass as on the major raw resource for future chemistry and a fuel industry. The significant potential for perfection of biomass conversion processes is concentrated in the field of radiation-chemical methods. Both the mode of post-radiation distillation and mode of electron-beam distillation of biomass have been investigated as well as the mode of gas-phase synthesis of liquid engine fuel from of biomass distillation products. Synergistic action of radiation and temperature has been analyzed at use of the accelerated electron beams allowing to combine radiolysis with effective radiation heating of a material without use of additional heaters. At dose rate above 1 kGy/s the electron-beam irradiation results in intensive decomposition of a biomass and evaporation of formed fragments with obtaining of a liquid condensate (∼ 60 wt%), CO 2 and Co gases (13-18 wt%) and charcoal in the residue. Biomass distillation at radiation heating allows to increase almost three times an organic liquid yield in comparison with pyrolysis. The majority of liquid products from cellulose is represented by the furan derivatives considered among the very perspective components for alternative engine fuels. Distilled-off gases and vapors are diluted with gaseous C 1 -C 5 alkanes and again are exposed to an irradiation to produce liquid fuel from a biomass. This transformation is based on a method of electron-beam circulation conversion of gaseous C 1 -C 5 alkanes (Ponomarev, A.V., Radiat. Phys. Chem., 78, 48, 2009) which consists in formation and removal of liquid products with high degree of carbon skeleton branching. The isomers ratio in a liquid may be controlled by means of change of an irradiation condition and initial gas composition. The irradiation of gaseous alkanes together with vaporous products of biomass destruction allows to synthesize the fuel enriched by conventional

  12. Synthesis and Cytotoxicity of Novel Hexahydrothienocycloheptapyridazinone Derivatives

    Directory of Open Access Journals (Sweden)

    Irene Marchesi

    2009-09-01

    Full Text Available Designed as a new group of tricyclic molecules containing the thienocycloheptapyridazinone ring system, a number of 2N-substituted-hexahydrothienocycloheptapyridazinone derivatives were synthesized and their biological activity evaluated. Among the synthesized compounds, derivatives 7d and 7h were found to possess cytotoxic activity against non-small cell lung cancer and central nervous system cancer cell lines, respectively.

  13. 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.

  14. 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.

  15. SYNTHESIS OF SUBSTITUTED FLAVONE DERIVATIVES AS ...

    African Journals Online (AJOL)

    Preferred Customer

    Flavone (2-phenylchromone) derivatives are naturally occurring heterocyclic compound belongs to the flavanoid group. It showed significant role in pharmaceutical effects [1] including leishmanicidal activity, oviposter stimulant phytoalexins, anti-HIV, vasodilator, antiviral, anti- oxidants, bactericidal, DNA cleavage, ...

  16. Synthesis and Biological Evaluation of Resveratrol Derivatives as Melanogenesis Inhibitors

    Directory of Open Access Journals (Sweden)

    Qing Liu

    2015-09-01

    Full Text Available Resveratrol (1, a naturally occurring stilbene compound, has been suggested as a potential whitening agent with strong inhibitory activity on melanin synthesis. However, the use of resveratrol in cosmetics has been limited due to its chemical instability and poor bioavailability. Therefore, resveratrol derivatives were prepared to improve bioavailability and anti-melanogenesis activity. Nine resveratrol derivatives including five alkyl ether derivatives with C2H5, C4H9, C5H11, C6H13, and C8H17 (2a–2e and four ester derivatives with CH3, CH=C(CH32, CH(C2H5C4H9, C7H15 (3a–3d were newly synthesized and their effect on melanin synthesis were assessed. All the synthetic derivatives efficiently reduced the melanin content in α-MSH stimulated B16F10 melanoma cells. Further investigation showed that the inhibitory effect of 2a on melanin synthesis was achieved not by the inhibition of tyrosinase activity but by the inhibition of melanogenic enzyme expressions such as tyrosinase and tyrosinase-related protein (TRP-1. Our synthetic resveratrol derivatives have more lipophilic properties than resveratrol by the addition of alkyl or acyl chains to free hydroxyl moiety of resveratrol; thus, they are expected to show better bioavailability in skin application. Therefore, we suggest that our synthetic resveratrol derivatives might be promising candidates for better practical application to skin-whitening cosmetics.

  17. Synthesis and characterization of novel sulfonamides derivatives

    African Journals Online (AJOL)

    3Department of Chemistry, Comsat Institute of Information & Technology Riawind road. Lahore ... Newer sulfonamides and their derivatives has obtained great attention in pharmaceutical field in ... MS data was recorded on Finnigan MAT 112 mass ..... potent and orally active sulfonamide ETB selective antagonists. Bioorg.

  18. Synthesis of hydroxy derivatives of limonene

    International Nuclear Information System (INIS)

    Ardashov, O V; Volcho, K P; Salakhutdinov, N F

    2014-01-01

    Synthetic routes to mono-, di- and trihydroxy derivatives of limonene are presented. Emphasis is given to the problems of regio- and stereoselectivity of transformations. Data on the isolation from natural sources and on the biological activities of the title compounds are given. The bibliography includes 107 references

  19. Synthesis gas production via hybrid steam reforming of natural gas and bio-liquids

    OpenAIRE

    Balegedde Ramachandran, P.

    2013-01-01

    This thesis deals with (catalytic) steam reforming of bio-liquids for the production of synthesis gas. Glycerol, both crude from the biodiesel manufacturing and refined, and pyrolysis oil are tested as bio-based feedstocks. Liquid bio-based feeds could be preferred over inhomogeneous fibrous solid biomass because of their logistic advantages, better mineral balance, and better processability. Especially the ease of pressurization, which is required for large scale synthesis gas production, is...

  20. SYNTHESIS, REACTIVITY AND BIOLOGICAL ACTIVITY OF QUINOXALIN-2-ONE DERIVATIVES

    OpenAIRE

    El Mokhtar Essassi; R. Bouhfid; Y. Kandri Rodi; S. Ferfra; H. Benzeid; Y. Ramli

    2010-01-01

    Quinoxalines have a great interest in various fields and particularly in chemistry, biology and pharmacology. It enabled the researchers to develop many methods for their preparations and to seek new fields of application. In this review, we’ll expose different methods of synthesis of the quinoxalin-2-one, its reactivity and finally we’ll discuss the various biological activities of its derivatives.

  1. Synthesis and antibacterial activity of novel enolphosphate derivatives.

    Science.gov (United States)

    Grison, Claude; Barthes, Nicolas; Finance, Chantal; Duval, Raphael E

    2010-10-01

    A new class of enolphosphates derivatives, the 1-alkenyldiphosphates, was designed and a rapid and efficient synthesis for these compounds was developed. These new molecules showed interesting in vitro antibacterial activities (MIC) against Gram-positive bacteria (Staphylococcus aureus) and Gram-negative pathogens including Pseudomonas aeruginosa and Escherichia coli. 2010 Elsevier Inc. All rights reserved.

  2. Synthesis of a 2-Furylpyrazoline Derivative Using Microwave Irradiation

    Directory of Open Access Journals (Sweden)

    Suban Syed Shafi

    2009-08-01

    Full Text Available A simple method for the synthesis of pyrazoline derivative containing furan moiety was developed. Thus, 5-(6-bromo-1,3-benzodioxol-5-yl-3-(2-furyl-1-(3-methyl-phenyl-4,5-dihydro-1H-pyrazole was synthesized using microwave irradiation and it was characterized by NMR, IR, and LCMS.

  3. Synthesis and molecular docking of new hydrazones derived from ...

    African Journals Online (AJOL)

    Synthesis and molecular docking of new hydrazones derived from ethyl isonipecotate and their biological activities. A Munir, Aziz-ur Rehman, M.A. Abbasi, S.Z. Siddiqui, A Nasir, S.G. Khan, S Rasool, S.A.A. Shah ...

  4. Air extraction in gas turbines burning coal-derived gas

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Tah-teh; Agrawal, A.K.; Kapat, J.S.

    1993-11-01

    In the first phase of this contracted research, a comprehensive investigation was performed. Principally, the effort was directed to identify the technical barriers which might exist in integrating the air-blown coal gasification process with a hot gas cleanup scheme and the state-of-the-art, US made, heavy-frame gas turbine. The guiding rule of the integration is to keep the compressor and the expander unchanged if possible. Because of the low-heat content of coal gas and of the need to accommodate air extraction, the combustor and perhaps, the flow region between the compressor exit and the expander inlet might need to be modified. In selecting a compressed air extraction scheme, one must consider how the scheme affects the air supply to the hot section of the turbine and the total pressure loss in the flow region. Air extraction must preserve effective cooling of the hot components, such as the transition pieces. It must also ensure proper air/fuel mixing in the combustor, hence the combustor exit pattern factor. The overall thermal efficiency of the power plant can be increased by minimizing the total pressure loss in the diffusers associated with the air extraction. Therefore, a study of airflow in the pre- and dump-diffusers with and without air extraction would provide information crucial to attaining high-thermal efficiency and to preventing hot spots. The research group at Clemson University suggested using a Griffith diffuser for the prediffuser and extracting air from the diffuser inlet. The present research establishes that the analytically identified problems in the impingement cooling flow are factual. This phase of the contracted research substantiates experimentally the advantage of using the Griffith diffuser with air extraction at the diffuser inlet.

  5. Energy derivatives, experiences in derivative trading from the natural gas industry : back to basics

    International Nuclear Information System (INIS)

    Dittmer, G.; Coyle, T.

    1998-01-01

    Some basic facts regarding derivatives in the electric power industry were discussed based on experiences in the natural gas industry. Derivatives were described as financial instruments that have no value of their own but derive their value from other assets, such as commodities. Futures and Options are the two forms of derivatives. Electricity as a commodity was characterized, and a historical parallel was drawn between deregulation in the natural gas and electric power industry. Short term and long term factors impacting the market and market dynamics impacting derivatives were identified. The latter include: (1) volatility, (2) liquidity, (3) correlations, and (4) price discovery. In contrast to the natural gas market, the electricity market is considered as lacking liquidity and in need of moving farther along the maturity timeline. The question of natural gas/ electricity convergence was also addressed refs., tabs., figs

  6. Advances in Isolation and Synthesis of Xanthone Derivatives

    Institute of Scientific and Technical Information of China (English)

    YANG Chun-hui; MA Li; WEI Zhen-ping; HAN Feng; GAO Jing

    2012-01-01

    Xanthone and its derivatives occupy a large part of the family of natural polyphenolic compounds with various biological and pharmacological activities.In recent years (from 2006 to 2011),it was reported that 127 xanthones were discovered from plants and fungi using various modem separation methods including silica gel/polyamide column chromatography,HPLC,high-speed counter-current chromatography,high-performance centrifugal partition chromatography,etc.Since total synthesis and structure modification for xanthone and its derivatives have been given attention worldwide,we introduced the synthetic methods of xanthone skeletons as well.Unfortunately,to date,there are still weaknesses in current methods of separation and synthesis,which need to be improved.This review,to a certain extent,provides necessary foundation for the further research and development of medicines containing xanthone and its derivatives.

  7. Synthesis, characterization and gas sensing performance

    Indian Academy of Sciences (India)

    For the first time, this study reports the gas sensing performance of aluminosilicate azide cancrinite. The effect of annealing andoperating temperature on gas sensing characteristic of azide cancrinite thick film is investigated systematically for various gases at different operating temperatures. This sensor was observed to be ...

  8. Synthesis of new derivatives of naphthalene

    International Nuclear Information System (INIS)

    Rivera Marrero, Suchitil; Sablon Carrazana, Marquiza; Lopez Barroso, Rosa Maria

    2011-01-01

    Alzheimer's disease (AD) is the most common cause of dementia and there is no cure for this disease. It is known that it is triggered by the apparition of the senile plaques produced for the agglomeration of β-amyloid peptides. AD's reliable diagnosis is done post-mortem. Recently, non-invasive methods are evaluated for in vivo diagnosis of this disease by means of imaging techniques PET (Positron Emission Tomography), SPECT (Single Photon Emission Computed Tomography) and MRI (Magnetic Resonance Imaging). In the case of the SPECT technique, new organic compounds labeled with radionuclides 1 23I , 1 25I , and 99 mT c have been described. Epidemiological studies have revealed that the use of non-steroidal anti-inflammatory drugs decreases the relative risk of AD. In the last years, the search of compounds with similar structures it has increased in order to be used as labels or drugs. The objective of this paper was to synthesize new naphthalene derivatives, for its further use as quelating agents of 99 mT c, for the detection of β-amyloid plaque in the AD. Thus, spacer arms with different lengths were introduced at β-position (or 1-) of naphthalene molecule through various different reactions. The compounds were structurally characterized by IR, 1 H -NMR and 13 C - NMR spectroscopies and mass spectrometry

  9. Salicylic acid derivatives: synthesis, features and usage as therapeutic tools.

    Science.gov (United States)

    Ekinci, Deniz; Sentürk, Murat; Küfrevioğlu, Ömer İrfan

    2011-12-01

    In the field of medicinal chemistry, there is a growing interest in the use of small molecules. Although acetyl salicylic acid is well known for medical applications, little is known about other salicylic acid derivatives, and there is serious lack of data and information on the effects and biological evaluation that connect them. This review covers the synthesis and drug potencies of salicylic acid derivatives. After a brief overview of the information on salicylic acid and its features, a detailed review of salicylic acids as drugs and prodrugs, usage as cyclooxygenase inhibitors, properties in plants, synthesis and recent patents, is developed. Salicylic acid research is still an important area and innovations continue to arise, which offer hope for new therapeutics in related fields. It is anticipated that this review will guide the direction of long-term drug/nutraceutical safety trials and stimulate ideas for future research.

  10. Synthesis and Electrical and Gas Sensing Properties of Some 5-(Quinolinylmethylene-2-thioxodihydropyrimidine-4,6(1H,5H-dione and 5-(Quinolinylmethylenepyrimidine-2,4,6(1H,3H,5H-trione Derivatives

    Directory of Open Access Journals (Sweden)

    H. Kerim Beker

    2013-01-01

    Full Text Available Eight new 5-(quinolinylmethylenebarbituric acid derivatives were synthesized by the reaction of 1,3-dimethylbarbituric acid and 1,3-diethyl-2-thiobarbituric acid with quinoline-4-carboxaldehydes and several quinoline-2-carboxaldehydes via Knoevenagel condensation. The novel compounds were characterized by 1H NMR, 13C NMR, mass, IR, and UV-visible spectral data and elemental analyses. d.c. and a.c. conduction properties of the compounds were investigated in the frequency range of 40–105 Hz and temperature range 295–440 K. The d.c. results showed an activated conductivity dependence on temperature for all films. Obtained data reveal that a.c. conductivity obeys the relation and exponent is found to decrease by increasing temperature. The analysis of the a.c. conduction data showed that the CBH model is the dominant conduction mechanism for the electron transport in the films. Gas sensing properties of the films for the volatile organic compounds (VOCs were also investigated in the same temperature range. Maximum sensitivity to VOCs was observed at around 360 K for compound 6.

  11. Evaluation of catalytic combustion of actual coal-derived gas

    Science.gov (United States)

    Blanton, J. C.; Shisler, R. A.

    1982-01-01

    The combustion characteristics of a Pt-Pl catalytic reactor burning coal-derived, low-Btu gas were investigated. A large matrix of test conditions was explored involving variations in fuel/air inlet temperature and velocity, reactor pressure, and combustor exit temperature. Other data recorded included fuel gas composition, reactor temperatures, and exhaust emissions. Operating experience with the reactor was satisfactory. Combustion efficiencies were quite high (over 95 percent) over most of the operating range. Emissions of NOx were quite high (up to 500 ppm V and greater), owing to the high ammonia content of the fuel gas.

  12. SYNTHESIS, REACTIVITY AND BIOLOGICAL ACTIVITY OF QUINOXALIN-2-ONE DERIVATIVES

    Directory of Open Access Journals (Sweden)

    El Mokhtar Essassi

    2010-04-01

    Full Text Available Quinoxalines have a great interest in various fields and particularly in chemistry, biology and pharmacology. It enabled the researchers to develop many methods for their preparations and to seek new fields of application. In this review, we’ll expose different methods of synthesis of the quinoxalin-2-one, its reactivity and finally we’ll discuss the various biological activities of its derivatives.

  13. Novel Thiazole Derivatives of Medicinal Potential: Synthesis and Modeling

    Directory of Open Access Journals (Sweden)

    Nour E. A. Abdel-Sattar

    2017-01-01

    Full Text Available This paper reports on the synthesis of new thiazole derivatives that could be profitably exploited in medical treatment of tumors. Molecular electronic structures have been modeled within density function theory (DFT framework. Reactivity indices obtained from the frontier orbital energies as well as electrostatic potential energy maps are discussed and correlated with the molecular structure. X-ray crystallographic data of one of the new compounds is measured and used to support and verify the theoretical results.

  14. Biological conversion of coal synthesis gas to methane

    Energy Technology Data Exchange (ETDEWEB)

    Barik, S; Corder, R E; Clausen, E C; Gaddy, J L

    1987-09-01

    High temperatures and pressures are required, and therefore, high costs incurred during catalytic upgrading of coal synthesis gas to methane. Thus, the feasibility of biological reactions in converting synthesis gas to methane has been demonstrated in mixed and pure cultures. Complete conversion has been achieved in 2 hours with a mixed culture, and 45 minutes to 1.5 hours in pure cultures of P. productus and Methanothrix sp.. Typical sulfur levels involved during the process are found not to inhibit the bacteria and so sulfur does not have to be removed prior to biomethanation. Preliminary economic analyses indicate that coal gas may be biologically methanated for 50-60 cents/million Btu. Further studies with pure culture bacteria and increased pressure are expected to enhance biomethanation economics.

  15. Synthesis, characterization and gas sensing property of ...

    Indian Academy of Sciences (India)

    Unknown

    et al 2000), drug delivery system (Panda et al 2001) and fuel cells (Gross et al 1998a; Verges et al 2000). It has promising application as a chemical gas sensor (Nagai et al .... apatite biomaterial ceramic was compacted into a pellet of 1⋅0 cm diameter having 0⋅15 cm thickness using poly- vinyl alcohol as binder material.

  16. NOVEL REACTOR FOR THE PRODUCTION OF SYNTHESIS GAS

    Energy Technology Data Exchange (ETDEWEB)

    Vasilis Papavassiliou; Leo Bonnell; Dion Vlachos

    2004-12-01

    Praxair investigated an advanced technology for producing synthesis gas from natural gas and oxygen This production process combined the use of a short-reaction time catalyst with Praxair's gas mixing technology to provide a novel reactor system. The program achieved all of the milestones contained in the development plan for Phase I. We were able to develop a reactor configuration that was able to operate at high pressures (up to 19atm). This new reactor technology was used as the basis for a new process for the conversion of natural gas to liquid products (Gas to Liquids or GTL). Economic analysis indicated that the new process could provide a 8-10% cost advantage over conventional technology. The economic prediction although favorable was not encouraging enough for a high risk program like this. Praxair decided to terminate development.

  17. Technologies for direct production of flexible H2/CO synthesis gas

    International Nuclear Information System (INIS)

    Song Xueping; Guo Zhancheng

    2006-01-01

    The use of synthesis gas offers the opportunity to furnish a broad range of environmentally clean fuels and high value chemicals. However, synthesis gas manufacturing systems based on natural gas are capital intensive, and hence, there is great interest in technologies for cost effective synthesis gas production. Direct production of synthesis gas with flexible H 2 /CO ratio, which is in agreement with the stoichiometric ratios required by major synthesis gas based petrochemicals, can decrease the capital investment as well as the operating cost. Although CO 2 reforming and catalytic partial oxidation can directly produce desirable H 2 /CO synthesis gas, they are complicated and continued studies are necessary. In fact, direct production of flexible H 2 /CO synthesis gas can be obtained by optimizing the process schemes based on steam reforming and autothermal reforming as well as partial oxidation. This paper reviews the state of the art of the technologies

  18. Room-temperature Electrochemical Synthesis of Carbide-derived Carbons and Related Materials

    Energy Technology Data Exchange (ETDEWEB)

    Gogotsi, Yury [Drexel Univ., Philadelphia, PA (United States). Nanomaterials Group. Materials Science and Engineering Dept.

    2015-02-28

    This project addresses room-temperature electrochemical etching as an energy-efficient route to synthesis of 3D nanoporous carbon networks and layered 2D carbons and related structures, as well as provides fundamental understanding of structure and properties of materials produced by this method. Carbide-derived-carbons (CDCs) are a growing class of nanostructured carbon materials with properties that are desirable for many applications, such as electrical energy and gas storage. The structure of these functional materials is tunable by the choice of the starting carbide precursor, synthesis method, and process parameters. Moving from high-temperature synthesis of CDCs through vacuum decomposition above 1400°C and chlorination above 400°C, our studies under the previous DOE BES support led to identification of precursor materials and processing conditions for CDC synthesis at temperatures as low as 200°C, resulting in amorphous and highly reactive porous carbons. We also investigated synthesis of monolithic CDC films from carbide films at 250-1200°C. The results of our early studies provided new insights into CDC formation, led to development of materials for capacitive energy storage, and enabled fundamental understanding of the electrolyte ions confinement in nanoporous carbons.

  19. Synthesis of Zeolite Materials for Noble Gas Separation

    International Nuclear Information System (INIS)

    Achey, R.; Rivera, O.; Wellons, M.; Hunter, D.

    2017-01-01

    Microporous zeolite adsorbent materials are widely used as a medium for separating gases. Adsorbent gas separation systems can run at ambient temperature and require minimal pressure to flow the input gas stream across the adsorbent bed. This allows for low energy consumption relative to other types of separation systems. Specific zeolites also have a high capacity and selectivity for the gases of interest, leading to compact and efficient separation systems. These characteristics are particularly advantageous for the application of signatures detection for non-proliferation, which often requires portable systems with low power draw. Savannah River National Laboratory currently is the leader in using zeolites for noble gas sampling for non-proliferation detection platforms. However, there is a constant customer need for improved sampling capabilities. Development of improved zeolite materials will lead to improved sampling technology. Microwave-assisted and conventional hydrothermal synthesis have been used to make a variety of zeolites tailored for noble gas separation. Materials characterization data collected in this project has been used to help guide the synthesis of improved zeolite materials. Candidate materials have been down-selected based on highest available surface area, maximum overall capacity for gas adsorption and highest selectivity. The creation of improved adsorbent materials initiated in this project will lead to development of more compact, efficient and effective noble gas collectors and concentrators. The work performed in this project will be used as a foundation for funding proposals for further material development as well as possible industrial applications.

  20. Synthesis of Zeolite Materials for Noble Gas Separation

    Energy Technology Data Exchange (ETDEWEB)

    Achey, R. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Rivera, O. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Wellons, M. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Hunter, D. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2017-10-02

    Microporous zeolite adsorbent materials are widely used as a medium for separating gases. Adsorbent gas separation systems can run at ambient temperature and require minimal pressure to flow the input gas stream across the adsorbent bed. This allows for low energy consumption relative to other types of separation systems. Specific zeolites also have a high capacity and selectivity for the gases of interest, leading to compact and efficient separation systems. These characteristics are particularly advantageous for the application of signatures detection for non-proliferation, which often requires portable systems with low power draw. Savannah River National Laboratory currently is the leader in using zeolites for noble gas sampling for non-proliferation detection platforms. However, there is a constant customer need for improved sampling capabilities. Development of improved zeolite materials will lead to improved sampling technology. Microwave-assisted and conventional hydrothermal synthesis have been used to make a variety of zeolites tailored for noble gas separation. Materials characterization data collected in this project has been used to help guide the synthesis of improved zeolite materials. Candidate materials have been down-selected based on highest available surface area, maximum overall capacity for gas adsorption and highest selectivity. The creation of improved adsorbent materials initiated in this project will lead to development of more compact, efficient and effective noble gas collectors and concentrators. The work performed in this project will be used as a foundation for funding proposals for further material development as well as possible industrial applications.

  1. Synthesis gas production from various biomass feedstocks

    Directory of Open Access Journals (Sweden)

    Juan A. Conesa

    2013-10-01

    Full Text Available The decomposition of five different biomass samples was studied in a horizontal laboratory reactor. The samples consisted of esparto grass, straw, Posidonea Oceanic seaweed, waste from urban and agricultural pruning and waste from forest pruning. Both pyrolysis in inert atmosphere and combustion in the presence of oxygen were studied. Different heating rates were used by varying the input speed. Major gas compounds were analyzed. The experimental results show that the amount of CO formed is lower in less dense species. It is also found that there is an increase of hydrocarbons formed at increasing feeding rates, in particular methane, while there is a decrease in the production of hydrogen.

  2. HIGH EFFICIENCY DESULFURIZATION OF SYNTHESIS GAS

    Energy Technology Data Exchange (ETDEWEB)

    Kwang-Bok Yi; Anirban Mukherjee; Elizabeth J. Podlaha; Douglas P. Harrison

    2004-03-01

    Mixed metal oxides containing ceria and zirconia have been studied as high temperature desulfurization sorbents with the objective of achieving the DOE Vision 21 target of 1 ppmv or less H{sub 2}S in the product gas. The research was justified by recent results in this laboratory that showed that reduced CeO{sub 2}, designated CeOn (1.5 < n < 2.0), is capable of achieving the 1 ppmv target in highly reducing gas atmospheres. The addition of ZrO{sub 2} has improved the performance of oxidation catalysts and three-way automotive catalysts containing CeO{sub 2}, and was postulated to have similar beneficial effects on CeO{sub 2} desulfurization sorbents. An electrochemical method for synthesizing CeO{sub 2}-ZrO{sub 2} mixtures was developed and the products were characterized by XRD and TEM during year 01. Nanocrystalline particles having a diameter of about 5 nm and containing from approximately 10 mol% to 80 mol% ZrO{sub 2} were prepared. XRD analysis showed the product to be a solid solution at low ZrO{sub 2} contents with a separate ZrO{sub 2} phase emerging at higher ZrO{sub 2} levels. Unfortunately, the quantity of CeO{sub 2}-ZrO{sub 2} that could be prepared electrochemically was too small to permit desulfurization testing. Also during year 01 a laboratory-scale fixed-bed reactor was constructed for desulfurization testing. All components of the reactor and analytical systems that were exposed to low concentrations of H{sub 2}S were constructed of quartz, Teflon, or silcosteel. Reactor product gas composition as a function of time was determined using a Varian 3800 gas chromatograph equipped with a pulsed flame photometric detector (PFPD) for measuring low H{sub 2}S concentrations from approximately 0.1 to 10 ppmv, and a thermal conductivity detector (TCD) for higher concentrations of H{sub 2}S. Larger quantities of CeO{sub 2}-ZrO{sub 2} mixtures from other sources, including mixtures prepared in this laboratory using a coprecipitation procedure, were obtained

  3. Synthesis of templated carbons starting from clay and clay-derived zeolites for hydrogen storage applications

    CSIR Research Space (South Africa)

    Musyoka, Nicholas M

    2014-10-01

    Full Text Available 57 58 59 60 For Peer Review 1 Synthesis of templated carbons starting from clay and clay-derived zeolites for hydrogen storage applications N. M. Musyoka1*, J. Ren1, H. W. Langmi1, D. E. C. Rogers1, B. C. North1, M. Mathe1 and D. Bessarabov2... clear (filtered) extract of cloisite clay, SNC for zeolite from unfiltered cloisite clay extract and SBC for zeolite from unfiltered South African bentonite clay extract. Furfuryl alcohol (Sigma Aldrich, C5H6O2, 98%) and Ethylene gas were used...

  4. ISOBUTANOL-METHANOL MIXTURES FROM SYNTHESIS GAS

    Energy Technology Data Exchange (ETDEWEB)

    Enrique Iglesia

    1998-09-01

    Isobutanol is potential as a fuel additive or precursor to methyl tert-butyl ether (MTBE). Alkali-promoted Cu/ZnO/Al{sub 2}O{sub 3} and Cu/MgO/CeO{sub 2} materials have been found to catalyze the formation of isobutanol from CO and H{sub 2} at temperatures (573-623 K) that allow their use in slurry reactors. Our studies focus on the mechanism and structural requirements for selective isobutanol synthesis on these types of catalysts. Alkali promoted Cu/MgO/CeO{sub 2}, Cu/MgO/ZnO, and CuZnAlO{sub x} materials and their individual components Cu/MgO, MgO/CeO{sub 2}, MgO and CeO{sub 2} have been prepared for the use in kinetic studies of alcohol coupling reactions, in identification of reaction intermediates, and in isobutanol synthesis at high pressures. These samples were prepared by coprecipitation of mixed nitrate solutions with an aqueous solution of KOH (2M) and K{sub 2}CO{sub 3} (1M) at 338 K at a constant pH of 9, except for Cs-Cu/ZnO/Al{sub 2}O{sub 3} at a pH of 7, in a well-stirred thermostated container. The precipitate was filtered, washed thoroughly with dioinized water at 303 K in order to remove residual K ions, and dried at 353 K overnight. Dried samples were calcined at 723 K, except for Cs-Cu/ZnO/Al{sub 2}O{sub 3} at 623 K, for 4 h in order to form the corresponding mixed oxides. Alkali addition (K or Cs) was performed by incipient wetness using K{sub 2}CO{sub 3} (0.25 M) and CH{sub 3}COOCs (0.25 M) aqueous solutions. The crystallinity and phase structures of resulting materials were analyzed by powered X-ray diffraction.

  5. Synthesis and antifungal activity of new salicylic acid derivatives

    Directory of Open Access Journals (Sweden)

    Wodnicka Alicja

    2017-03-01

    Full Text Available A simple one-step procedure for synthesis of 1-methoxy-1-oxoalkan-2-yl salicylates and 1-methoxy-1-oxoalkan-2-yl 2-[(1-methoxy-1-oxoalkan-2-yloxy]benzoates by reaction of salicylic acid with several methyl 2-bromoalkanoates was developed. The reactions were carried out in N,N-dimethylformamide (DMF in the presence of anhydrous potassium carbonate. Conditions for regioselective synthesis of target compounds were established. The developed procedure could be easily applied in the industrial production process. The new salicylic acid derivatives were obtained with satisfactory yields and were characterized by MS and 1H NMR spectra. The fungicidal activity of the prepared compounds was tested in vitro against seven species of plant pathogenic fungi. The best results were observed for 1-methoxy-1-oxoalkan-2-yl salicylates which showed moderate or good activity against Botrytis cinerea and Rhizoctonia solani.

  6. Oxygenated base chemicals from synthesis gas

    Energy Technology Data Exchange (ETDEWEB)

    Roeper, M.

    1984-11-01

    Methyl formate, a syngas based intermediate, is already today produced on large scale by base catalyzed methanol carbonylation. An alternative synthesis, based on methanol dehydrogenation, seems to be ready for commercialization, whereas other routes including direct carbon monoxide hydrogenation, formaldehyde disproportionation or methanol oxydehydrogenation are less advanced. Besides being used as a solvent or an insect control agent, methyl formate serves as a feedstock for e.g. formic acid, formamide, N,N-dimethylformamide, and N-formyl morpholine. Newer formic acid processes are based on direct hydrolysis of methyl formate, and appear to replace the traditional indirect formamide based route. Future use of methyl formate could include the production of pure carbon monoxide, methanol, dimethyl carbonate, diphosgene, ethylene glycol via methyl glycolate, acetic acid, and methyl propionate. All these processes either avoid the use of high purity carbon monoxide or proceed under milder conditions than conventional routes. They could gain interest, if syngas and methanol become available at a large scale as competitive feedstocks for the chemical industry.

  7. HIGH EFFICIENCY DESULFURIZATION OF SYNTHESIS GAS

    Energy Technology Data Exchange (ETDEWEB)

    Anirban Mukherjee; Kwang-Bok Yi; Elizabeth J. Podlaha; Douglas P. Harrison

    2001-11-01

    Mixed metal oxides containing CeO{sub 2} and ZrO{sub 2} are being studied as high temperature desulfurization sorbents capable of achieving the DOE Vision 21 target of 1 ppmv of less H{sub 2}S. The research is justified by recent results in this laboratory that showed that reduced CeO{sub 2}, designated CeO{sub n} (1.5 < n < 2.0), is capable of achieving the 1 ppmv target in highly reducing gas atmospheres. The addition of ZrO{sub 2} has improved the performance of oxidation catalysts and three-way automotive catalysts containing CeO{sub 2}, and should have similar beneficial effects on CeO{sub 2} desulfurization sorbents. An electrochemical method for synthesizing CeO{sub 2}-ZrO{sub 2} has been developed and the products have been characterized by XRD and TEM during year 01. Nanocrystalline particles having a diameter of about 5 nm and containing from approximately 10 mol% to 80 mol% ZrO{sub 2} have been prepared. XRD showed the product to be a solid solution at low ZrO{sub 2} contents with a separate ZrO{sub 2} phase emerging at higher ZrO{sub 2} levels. Phase separation did not occur when the solid solutions were heat treated at 700 C. A flow reactor system constructed of quartz and teflon has been constructed, and a gas chromatograph equipped with a pulsed flame photometric detector (PFPD) suitable for measuring sub-ppmv levels of H{sub 2}S has been purchased with LSU matching funds. Preliminary desulfurization tests using commercial CeO{sub 2} and CeO{sub 2}-ZrO{sub 2} in highly reducing gas compositions has confirmed that CeO{sub 2}-ZrO{sub 2} is more effective than CeO{sub 2} in removing H{sub 2}S. At 700 C the product H{sub 2}S concentration using CeO{sub 2}-ZrO{sub 2} sorbent was near the 0.1 ppmv PFPD detection limit during the prebreakthrough period.

  8. THE ECONOMICAL PRODUCTION OF ALCOHOL FUELS FROM COAL-DERIVED SYNTHESIS GAS. Includes quarterly technical progress report No.25 from 10/01/1997-12/31/1997, and quarterly technical progress report No.26 from 01/01/1998-03/31/1998; FINAL

    International Nuclear Information System (INIS)

    1999-01-01

    This project was divided into two parts. One part evaluated possible catalysts for producing higher-alcohols (C(sub 2) to C(sub 5+)) as fuel additives. The other part provided guidance by looking both at the economics of mixed-alcohol production from coal-derived syngas and the effect of higher alcohol addition on gasoline octane and engine performance. The catalysts studied for higher-alcohol synthesis were molybdenum sulfides promoted with potassium. The best catalysts produced alcohols at a rate of 200 g/kg of catalyst/h. Higher-alcohol selectivity was over 40%. The hydrocarbon by-product was less than 20%. These catalysts met established success criteria. The economics for mixed alcohols produced from coal were poor compared to mixed alcohols produced from natural gas. Syngas from natural gas was always less expensive than syngas from coal. Engine tests showed that mixed alcohols added to gasoline significantly improved fuel quality. Mixed-alcohols as produced by our catalysts enhanced gasoline octane and decreased engine emissions. Mixed-alcohol addition gave better results than adding individual alcohols as had been done in the 1980's when some refiners added methanol or ethanol to gasoline

  9. THE ECONOMICAL PRODUCTION OF ALCOHOL FUELS FROM COAL-DERIVED SYNTHESIS GAS. Includes quarterly technical progress report No.25 from 10/01/1997-12/31/1997, and quarterly technical progress report No.26 from 01/01/1998-03/31/1998

    Energy Technology Data Exchange (ETDEWEB)

    None

    1999-03-01

    This project was divided into two parts. One part evaluated possible catalysts for producing higher-alcohols (C{sub 2} to C{sub 5+}) as fuel additives. The other part provided guidance by looking both at the economics of mixed-alcohol production from coal-derived syngas and the effect of higher alcohol addition on gasoline octane and engine performance. The catalysts studied for higher-alcohol synthesis were molybdenum sulfides promoted with potassium. The best catalysts produced alcohols at a rate of 200 g/kg of catalyst/h. Higher-alcohol selectivity was over 40%. The hydrocarbon by-product was less than 20%. These catalysts met established success criteria. The economics for mixed alcohols produced from coal were poor compared to mixed alcohols produced from natural gas. Syngas from natural gas was always less expensive than syngas from coal. Engine tests showed that mixed alcohols added to gasoline significantly improved fuel quality. Mixed-alcohols as produced by our catalysts enhanced gasoline octane and decreased engine emissions. Mixed-alcohol addition gave better results than adding individual alcohols as had been done in the 1980's when some refiners added methanol or ethanol to gasoline.

  10. Proceedings of the DGMK-conference 'Synthesis gas chemistry'. Authors' manuscripts

    Energy Technology Data Exchange (ETDEWEB)

    Hoenicke, D.; Kohlpaintner, C.; Luecke, B.; Reschetilowski, W. [eds.

    2000-07-01

    The main topics of the DGMK-Conference ''Synthesis Gas Chemistry'' were: production of synthesis gas from several educts, new catalysts, Fischer-Tropsch synthesis, hydroformylation, steam reforming and carbonylation.

  11. Synthesis gas production via hybrid steam reforming of natural gas and bio-liquids

    NARCIS (Netherlands)

    Balegedde Ramachandran, P.

    2013-01-01

    This thesis deals with (catalytic) steam reforming of bio-liquids for the production of synthesis gas. Glycerol, both crude from the biodiesel manufacturing and refined, and pyrolysis oil are tested as bio-based feedstocks. Liquid bio-based feeds could be preferred over inhomogeneous fibrous solid

  12. Synthesis and Characterization of Biscoumarin and Benzopyrano Dicoumarin Derivatives

    International Nuclear Information System (INIS)

    Nik Khairunissa' Nik Abdullah Zawawi; Muhammad Taha; Norizan Ahmat; Nor Hadiani Ismail; Nik Khairunissa' Nik Abdullah Zawawi; Muhammad Taha; Norizan Ahmat; Nor Hadiani Ismail

    2016-01-01

    The wide-ranging biological activities of 4-hydroxycoumarin have stimulated considerable interest in this class of compounds, and various biscoumarin derivatives have been synthesized. Recently, a number of methods have been reported for the synthesis of biscoumarin by the reaction of 4-hydroxycoumarin and various aldehydes in the presence of catalysts. In the present study, a new series of biscoumarin and benzopyrano dicoumarin were synthesized and physically characterized by nuclear magnetic resonane ( 1 H and 13 C NMR), fourier transform infrared spectroscopy (FTIR), mass spectrometry (MS) and melting point. (author)

  13. SYNTHESIS OF FLAVANONE-6-CARBOXYLIC ACID DERIVATIVES FROM SALICYLIC ACID DERIVATIVE

    Directory of Open Access Journals (Sweden)

    Muhammad Idham Darussalam Mardjan

    2012-02-01

    Full Text Available Synthesis of flavanone-6-carboxylic acid derivatives had been conducted via the route of chalcone. The synthesis was carried out from salicylic acid derivative, i.e. 4-hydroxybenzoic acid, via esterification, Fries rearrangement, Claisen-Schmidt condensation and 1,4-nucleophilic addition reactions. Structure elucidation of products was performed using FT-IR, 1H-NMR, GC-MS and UV-Vis spectrometers. Reaction of 4-hydroxybenzoic acid with methanol catalyzed with sulfuric acid produced methyl 4-hydroxybenzoate in 87% yield. The acid-catalyzed-acetylation of the product using acetic anhydride gave methyl 4-acetoxybenzoate in 75% yield. Furthermore, solvent-free Fries rearrangement of methyl 4-acetoxybenzoate in the presence of AlCl3 produced 3-acetyl-4-hydroxybenzoic acid as the acetophenone derivatives in 67% yield. Then, Claisen-Schmidt condensation of the acetophenone and benzaldehyde derivatives of p-anisaldehyde and veratraldehyde in basic condition gave 2'-hydroxychalcone-5'-carboxylic acid derivatives  in 81 and 71 % yield, respectively. Finally, the ring closure reaction of the chalcone yielded the corresponding flavanone-6-carboxylic acids in 67 and 59% yield, respectively.

  14. Moderate temperature gas purification system: Application to high calorific coal-derived fuel

    Energy Technology Data Exchange (ETDEWEB)

    Kobayashi, M.; Shirai, H.; Nunokawa, M. [Central Research Institute of Electric Power Industry, Kanagawa (Japan)

    2008-01-15

    Simultaneous removal of dust, alkaline and alkaline-earth metals, halides and sulfur compounds is required to enlarge application of coal-derived gas to the high-temperature fuel cells and the fuel synthesis through chemical processing. Because high calorific fuel gas, such as oxygen-blown coal gas, has high carbon monoxide content, high-temperature (above 450{sup o}C) gas purification system is always subjected to the carbon deposition. We suggest moderate temperature (around 300{sup o}C) operation of the gas purification system to avoid the harmful disproportionation reaction and efficient removal of the various contaminants. Because the reaction rate is predominant to the performance of contaminant removal in the moderate temperature gas purification system, we evaluated the chemical removal processes; performance of the removal processes for halides and sulfur compounds was experimentally evaluated. The halide removal process with sodium aluminate sorbent had potential performance at around 300{sup o}C. The sulfur removal process with zinc ferrite sorbent was also applicable to the temperature range, though the reaction kinetics of the sorbent is essential to be approved.

  15. Moderate temperature gas purification system: application to high calorific coal derived fuel

    Energy Technology Data Exchange (ETDEWEB)

    M. Kobayashi; H. Shirai; M. Nunokawa [Central Research Institute of Electric Power Industry (CRIEPI), Kanagawa (Japan)

    2005-07-01

    Simultaneous removal of dust, alkaline and alkaline-earth metals, halides and sulfur compounds is required to enlarge application of coal-derived gas to the high temperature fuel cells and the fuel synthesis through chemical processing. Because high calorific fuel gas, such as oxygen-blown coal gas, has high carbon monoxide content, high temperature gas purification system is always subjected to the carbon deposition and slippage of contaminant of high vapor pressure. It was suggested that moderate temperature operation of the gas purification system is applied to avoid the harmful disproportionation reaction and efficient removal of the various contaminants. To establish the moderate temperature gas purification system, the chemical-removal processes where the reaction rate is predominant to the performance of contaminant removal should be evaluated. Performance of the removal processes for halides and sulfur compounds were experimentally evaluated. The halide removal process with sodium based sorbent had potential good performance at around 300{sup o}C. The sulfur removal process was also applicable to the temperature range, although the improvement of the sulfidation reaction rate is considered to be essential. 11 refs., 8 figs., 1 tab.

  16. Thermodynamic models to predict gas-liquid solubilities in the methanol synthesis, the methanol-higher alcohol synthesis, and the Fischer-Tropsch synthesis via gas-slurry processes

    NARCIS (Netherlands)

    Breman, B.B; Beenackers, A.A C M

    1996-01-01

    Various thermodynamic models were tested concerning their applicability to predict gas-liquid solubilities, relevant for synthesis gas conversion to methanol, higher alcohols, and hydrocarbons via gas-slurry processes. Without any parameter optimization the group contribution equation of state

  17. France independent on gas by 2050. A 100 pc renewable gas mix by 2050? Study synthesis

    International Nuclear Information System (INIS)

    Chapelon, Guillain; Rabetsimamanga, Ony; Bosso, Valerie; Frederic, Sylvain; Legrand, Stephanie; Leboul-Proust, Catherine; Monin, William; Singly, Bertrand de; Combet, Emmanuel; Marchal, David; Meunier, Laurent; Varet, Anne; Vincent, Isabelle; Antoine, Loic; Bardinal, Marc; Bastide, Guillaume; Bodineau, Luc; Canal, David; El Khamlichi, Aicha; Gagnepain, Bruno; Mainsant, Arnaud; Parrouffe, Jean-Michel; Pouet, Jean-Christophe; Theobald, Olivier; Vidalenc, Eric; Thomas, Alban; Madiec, Philippe; Meradi, Sabra; Boure, Quentin; Cherrey, Marc; Coupe, Florian; Couturier, Christian; Metivier, Simon; Chiche, Alice

    2018-01-01

    This document proposes a synthesis of a study which aimed at determining what could be an available renewable or recovery gas resource by 2050 in metropolitan France, whether it would be sufficient to face gas demand every day and at any point of the network, which network or production sector evolutions would be needed, which are the available constraints and leeway, and which would be the impact on the average cost of supplied gas. Potential renewable resources come from methanization, pyro-gasification, and power-to-gas. The production mix assessment is based on an ADEME scenario for 2035-2050. Four scenarios have been defined to assess the different hypotheses, notably resources: a 100 per cent renewable and recovery energies, a 100 per cent renewable and recovery energies with a high pyro-gasification, a 100 per cent renewable and recovery energies with a biomass restrained to gas usages, and a 75 per cent renewable and recovery. Results are presented in terms of theoretical potential, gas demand meeting, cost, and avoided emissions. Lessons learned concern the possibility of a 100 per cent renewable gas system with necessary evolutions, and a complementarity between the gas and electric networks. Limitations and perspectives are discussed

  18. Synthesis and applications of MOF-derived porous nanostructures

    Directory of Open Access Journals (Sweden)

    Min Hui Yap

    2017-07-01

    Full Text Available Metal organic frameworks (MOFs represent a class of porous material which is formed by strong bonds between metal ions and organic linkers. By careful selection of constituents, MOFs can exhibit very high surface area, large pore volume, and excellent chemical stability. Research on synthesis, structures and properties of various MOFs has shown that they are promising materials for many applications, such as energy storage, gas storage, heterogeneous catalysis and sensing. Apart from direct use, MOFs have also been used as support substrates for nanomaterials or as sacrificial templates/precursors for preparation of various functional nanostructures. In this review, we aim to present the most recent development of MOFs as precursors for the preparation of various nanostructures and their potential applications in energy-related devices and processes. Specifically, this present survey intends to push the boundaries and covers the literatures from the year 2013 to early 2017, on supercapacitors, lithium ion batteries, electrocatalysts, photocatalyst, gas sensing, water treatment, solar cells, and carbon dioxide capture. Finally, an outlook in terms of future challenges and potential prospects towards industrial applications are also discussed. Keywords: Metal organic frameworks, Porous nanostructures, Supercapacitors, Lithium ion batteries, Heterogeneous catalyst

  19. Synthesis and Antibacterial Activity of Some New Phenothiazine Derivatives

    Directory of Open Access Journals (Sweden)

    Pawan Kumar Swarnkar

    2007-01-01

    Full Text Available A series of some new phenothiazine derivatives were synthesized with the objective for evaluation as antimicrobials. The title compounds were prepared by a five step synthesis scheme. 2-Amino-6-substituted benzothiazoles (1 on diazotization afford 6-substituted benzothiazolyl-2-diazonium chlorides (2. Reaction of 2 with cold solution of β-naphthol in dilute NaOH furnishes α-(2-diazo-6-substituted benzothiazolyl- β-sodionaphthoxides (3 which on acidification with concentrated HCl gives α-(2-diazo-6-substituted benzothiazolyl-β-naphthols (4. Reaction of 4 with p-substituted anilines gives α-(2-diazo-6-substituted benzothiazolyl-β-(p-substituted anilino naphthalenes (5. This synthesis besides by using conventional methods was also attempted using microwave. Fusion of 5 with sulphur in presence of iodine results in α-(2-diazo-6-substituted benzothiazolyl-6- substituted [2, 3-b] benzophenothiazines(6. The structures of all these compounds have been supported by elemental analysis and their spectral studies. All synthesized compounds were tested for their antibacterial activity using standard drugs.

  20. Proficient synthesis of bioactive annulated pyrimidine derivatives: A review

    Directory of Open Access Journals (Sweden)

    Ajmal R. Bhat

    2017-11-01

    Full Text Available Syntheses of bioactive annulated pyrimidine derivatives are the most significant tasks in N-heterocyclic chemistry because these compounds have proved to be very attractive and useful for the design of new molecular frameworks of potential drugs with varying pharmacological activities. This review paper summarizes the one-pot multicomponent synthesis of annulated nitrogen- and oxygen-containing heterocycles, such as pyrano[2,3-d]pyrimidines, pyrido[2,3-d]pyrimidines and pyrido[2,3-d;5-6-d]dipyrimidines. The synthetic procedure is based on the chemistry of the domino Knoevenagel-Michael addition mechanism. Keywords: Pyrano[2,3-d]pyrimidines, Pyrido[2,3-d]pyrimidines, Pyrido[2,3-d;5-6-d]dipyrimidines, Barbituric acid/Thio-barbituric acid, Aromatic aldehydes, 6-aminouracil

  1. Design, Synthesis, and Antibacterial Activities of Novel Heterocyclic Arylsulphonamide Derivatives.

    Science.gov (United States)

    Singh, Anuradha; Srivastava, Ritika; Singh, Ramendra K

    2017-02-13

    Design, synthesis, and antibacterial activities of a series of arylsulphonamide derivatives as probable peptide deformylase (PDF) inhibitors have been discussed. Compounds have been designed following Lipinski's rule and after docking into the active site of PDF protein (PDB code: 1G2A) synthesized later on. Furthermore, to assess their antibacterial activity, screening of the compound was done in vitro conditions against Gram-positive and Gram-negative bacterial strains. In silico, studies revealed these compounds as potential antibacterial agents and this fact was also supported by their prominent scoring functions. Antibacterial results indicated that these molecules possessed a significant activity against Staphylococcus aureus, Bacillus cereus, Pseudomonas aeruginosa, and Escherichia coli with MIC values ranging from 0.06 to 0.29 μM. TOPKAT results showed that high LD 50 values and the compounds were assumed non-carcinogenic when various animal models were studied computationally.

  2. Synthesis and Spectroscopic Characterization of Two Tetrasubstituted Cationic Porphyrin Derivatives

    Directory of Open Access Journals (Sweden)

    Newton M. Barbosa Neto

    2011-07-01

    Full Text Available An imidazolium tetrasubstituted cationic porphyrin derivative (the free base and its Zn(II complex with five-membered heterocyclic groups in the meso-positions were synthesized using microwave irradiation, and the compounds obtained characterized by 1H-NMR and mass spectrometry. We observed that under microwave irradiation the yield is similar to when the synthesis is performed under conventional heating, however, the time required to prepare the porphyrins decreases enormously. In order to investigate the electronic state of these compounds, we employed UV-Vis and fluorescence spectroscopy combined with quantum chemical calculations. The results reveal the presence, in both compounds, of a large number of electronic states involving the association between the Soret and a blue-shifted band. The Soret band in both compounds also shows a considerable solvent dependence. As for emission, these compounds present low quantum yield at room temperature and no solvent influence on the fluorescence spectra was observed.

  3. Synthesis of new Technetium 99 agents from aryl piperozine derivatives

    International Nuclear Information System (INIS)

    Zenati, Kaouther

    2012-01-01

    This work arises in the context of developing specific radiopharmaceuticals for serotoninergic 5-HT 1A receptors, for scintigraphic imaging by SPECT. these being involved in several neuropathology. Starting from new derivative of Technetium cytectrene bearing the methoxyphenyl piperazine moiety that have revealed an impressive brain uptake (2.47 pour cent ID/G), we thought to obtain an other radiocomplexe characterized by a more stable brain retention. To do this we added a spacer amino propyl to the first ligand 1-((2methoxyphenyl) piperazine carboxamide ferrocene, thus obtaining 1(3-aminopropyl) 4 (2-methoxyphenyl piperazine) ferrocene carboxamide. We report here the synthesis of the tricarbonyl 99mT c radioligand, its characterization and its biological study. The biodistribution is characterized by a very large uptake in the lungs and relatively slow depuration.Brain absorption is reduced compared to the analogue of origin with equivalent cerebral retention time.

  4. Synthesis and Antitumor Evaluation of Novel Bis-Triaziquone Derivatives

    Directory of Open Access Journals (Sweden)

    Yuh-Ling Lin

    2009-06-01

    Full Text Available Aziridine-containing compounds have been of interest as anticancer agents since late 1970s. The design, synthesis and study of triaziquone (TZQ analogues with the aim of obtaining compounds with enhanced efficacy and reduced toxicity are an ongoing research effort in our group. A series of bis-type TZQ derivatives has been prepared and their cytotoxic activities were investigated. The cytotoxicity of these bis-type TZQ derivatives were tested on three cancer lines, including breast cancer (BC-M1, oral cancer (OEC-M1, larynx epidermal cancer (Hep2 and one normal skin fibroblast (SF. Most of these synthetic derivatives displayed significant cytotoxic activities against human carcinoma cell lines, but weak activities against SF. Among tested analogues the bis-type TZQ derivative 1a showed lethal effects on larynx epidermal carcinoma cells (Hep2, with an LC50 value of 2.02 mM, and also weak cytotoxic activity against SF cells with an LC50 value over 10 mM for 24 hr treatment. Comparing the viability of normal fibroblast cells treated with compound 1a and TZQ, the LC50 value of the latter was 2.52 mM, indicating more toxicity than compound 1a. This significantly decreased cytotoxicity of compound 1a towards normal SF cells, while still maintaining the anticancer activity towards Hep2 cells is an interesting feature. Among the seven compounds synthesized, compound 1c has similar toxicity effects on the three cancer cell lines and SF normal cells as the TZQ monomer.

  5. Coal pyrolysis under synthesis gas, hydrogen and nitrogen

    Energy Technology Data Exchange (ETDEWEB)

    Ariunaa, A.; Li Bao-Qing; Li Wen; Purevsuren, B. (and others) [Chinese Academy of Sciences, Taiyuan (China)

    2007-02-15

    Chinese Xundian, Mongolian Shiveeovoo lignites and Khoot oil shale are pyrolyzed under synthesis gas (SG) at temperature range from 400 to 800{sup o}C for lignite and from 300 to 600{sup o}C for oil shale with heating rate of 10{sup o}C/min in a fixed bed reactor. The results were compared with those obtained by pyrolysis under hydrogen and nitrogen. The results showed that unlike pyrolysis at high pressure, there are only slight different in the yields of char and tar among pyrolyses under various gases at room pressure for lignite, while higher liquid yield with lower yields of char and gas was obtained in pyrolysis of oil shale under SG and H{sub 2} than under N{sub 2}. It is found that the pyrite S can be easily removed to partially convert to organic S under various gaseous atmosphere and the total sulfur removal for oil shale is much less than lignite, which might be related to its high ash content. The higher total sulfur removal and less organic S content in the presence of SG in comparison with those under N{sub 2} and even under H{sub 2} in pyrolysis of Xundian lignite might result from the action of CO in SG. However, CO does not show its function in pyrolysis of Khoot oil shale, which might also be related to the high ash content. The results reported show the possibility of using synthesis gas instead of pure hydrogen as the reactive gas for coal hydropyrolysis. 11 refs., 4 figs., 6 tabs.

  6. Tritium labelled steroids, preparation process and application to synthesis of tritium labelled estrane derivatives

    International Nuclear Information System (INIS)

    1978-01-01

    Process for preparing new steroids labelled with tritium in 6.7 and comprising in 3 a blocked ketonic group as ketal, thioketal or derivatives. Application of these products to the synthesis of tritium labelled estrane derivatives [fr

  7. DEVELOPMENT OF ALTERNATIVE FUELS AND CHEMICALS FROM SYNTHESIS GAS

    Energy Technology Data Exchange (ETDEWEB)

    Peter J. Tijrn

    2003-05-31

    This Final Report for Cooperative Agreement No. DE-FC22-95PC93052, the ''Development of Alternative Fuels and Chemicals from Synthesis Gas,'' was prepared by Air Products and Chemicals, Inc. (Air Products), and covers activities from 29 December 1994 through 31 July 2002. The overall objectives of this program were to investigate potential technologies for the conversion of synthesis gas (syngas), a mixture primarily of hydrogen (H{sub 2}) and carbon monoxide (CO), to oxygenated and hydrocarbon fuels and industrial chemicals, and to demonstrate the most promising technologies at the LaPorte, Texas Alternative Fuels Development Unit (AFDU). Laboratory work was performed by Air Products and a variety of subcontractors, and focused on the study of the kinetics of production of methanol and dimethyl ether (DME) from syngas, the production of DME using the Liquid Phase Dimethyl Ether (LPDME{trademark}) Process, the conversion of DME to fuels and chemicals, and the production of other higher value products from syngas. Four operating campaigns were performed at the AFDU during the performance period. Tests of the Liquid Phase Methanol (LPMEOH{trademark}) Process and the LPDME{trademark} Process were made to confirm results from the laboratory program and to allow for the study of the hydrodynamics of the slurry bubble column reactor (SBCR) at a significant engineering scale. Two campaigns demonstrated the conversion of syngas to hydrocarbon products via the slurry-phase Fischer-Tropsch (F-T) process. Other topics that were studied within this program include the economics of production of methyl tert-butyl ether (MTBE), the identification of trace components in coal-derived syngas and the means to economically remove these species, and the study of systems for separation of wax from catalyst in the F-T process. The work performed under this Cooperative Agreement has continued to promote the development of technologies that use clean syngas produced

  8. Gas phase absorption studies of photoactive yellow protein chromophore derivatives.

    Science.gov (United States)

    Rocha-Rinza, Toms; Christiansen, Ove; Rajput, Jyoti; Gopalan, Aravind; Rahbek, Dennis B; Andersen, Lars H; Bochenkova, Anastasia V; Granovsky, Alexander A; Bravaya, Ksenia B; Nemukhin, Alexander V; Christiansen, Kasper Lincke; Nielsen, Mogens Brøndsted

    2009-08-27

    Photoabsorption spectra of deprotonated trans p-coumaric acid and two of its methyl substituted derivatives have been studied in gas phase both experimentally and theoretically. We have focused on the spectroscopic effect of the location of the two possible deprotonation sites on the trans p-coumaric acid which originate to either a phenoxide or a carboxylate. Surprisingly, the three chromophores were found to have the same absorption maximum at 430 nm, in spite of having different deprotonation positions. However, the absorption of the chromophore in polar solution is substantially different for the distinct deprotonation locations. We also report on the time scales and pathways of relaxation after photoexcitation for the three photoactive yellow protein chromophore derivatives. As a result of these experiments, we could detect the phenoxide isomer within the deprotonated trans p-coumaric acid in gas phase; however, the occurrence of the carboxylate is uncertain. Several computational methods were used simultaneously to provide insights and assistance in the interpretation of our experimental results. The calculated excitation energies S(0)-S(1) are in good agreement with experiment for those systems having a negative charge on a phenoxide moiety. Although our augmented multiconfigurational quasidegenerate perturbation theory calculations agree with experiment in the description of the absorption spectrum of anions with a carboxylate functional group, there are some puzzling disagreements between experiment and some calculational methods in the description of these systems.

  9. A novel chemo-enzymatic synthesis of hydrophilic phytosterol derivatives.

    Science.gov (United States)

    He, Wen-Sen; Hu, Di; Wang, Yu; Chen, Xue-Yan; Jia, Cheng-Sheng; Ma, Hai-Le; Feng, Biao

    2016-02-01

    In this study, a novel method was developed for chemo-enzymatic synthesis of hydrophilic phytosterol derivatives, phytosteryl polyethylene glycol succinate (PPGS), through an intermediate phytosteryl hemisuccinate (PSHS), which was first chemically prepared and subsequently coupled with polyethylene glycol (PEG) through lipase-catalyzed esterification. The chemical structure of intermediate and goal product were finally confirmed to be PSHS and PPGS by FT-IR, MS and NMR, suggesting that hydrophilic phytosterol derivatives were successfully synthesized. The effects of various parameters on the conversion of PSHS to PPGS were investigated and the highest conversion (>78%) was obtained under the selected conditions: 75 mmol/L PSHS, 1:2M ratio of PSHS to PEG, 50 g/L Novozym 435, 120 g/L 3 Å molecular sieves in tert-butanol, 55 °C, 96 h and 200 rpm. The solubility of phytosterols in water was significantly improved by coupling with PEG, facilitating the incorporation into a variety of foods containing water. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. Efficient synthesis of a fluorine-18 labeled biotin derivative

    International Nuclear Information System (INIS)

    Claesener, Michael; Breyholz, Hans-Jörg; Hermann, Sven; Faust, Andreas; Wagner, Stefan; Schober, Otmar; Schäfers, Michael; Kopka, Klaus

    2012-01-01

    Introduction: The natural occurring vitamin biotin, also known as vitamin H or vitamin B 7 , plays a major role in various metabolic reactions. Caused by its high binding affinity to the protein avidin with a dissociation constant of about 10 -15 M the biotin-avidin system was extensively examined for multiple applications. We have synthesized a fluorine-18 labeled biotin derivative [ 18 F]4 for a potential application in positron emission tomography (PET). Methods: Mesylate precursor 3 was obtained by an efficient two-step reaction via a copper catalyzed azide-alkyne cycloaddition (CuAAC) from easily accessible starting materials. [ 18 F]4 was successfully synthesized by a nucleophilic radiofluorination of precursor 3. A biodistribution study by means of small-animal PET imaging in wt-mice was performed and serum stability was examined. Results: Compound [ 18 F]4 was obtained from precursor compound 3 with an average specific activity of 16 GBq/μmol within 45 min and a radiochemical yield of 45 ± 5% (decay corrected). [ 18 F]4 demonstrated only negligible decomposition in human serum. A qualitative binding study revealed the high affinity of the synthesized biotin derivative to avidin. Blocking experiments with native biotin showed that binding was site-specific. Biodistribution studies showed that [ 18 F]4 was cleared quickly and efficiently from the body by hepatobiliary and renal elimination. Conclusion: An efficient synthesis for [ 18 F]4 was established. In vivo characteristics were determined and demonstrated the pharmacokinetic behaviour of [ 18 F]4.

  11. Performance of small-scale aero-derivative industrial gas turbines derived from helicopter engines

    Directory of Open Access Journals (Sweden)

    Barinyima Nkoi

    2013-12-01

    Full Text Available This paper considers comparative assessment of simple and advanced cycle small-scale aero-derivative industrial gas turbines derived from helicopter engines. More particularly, investigation was made of technical performance of the small-scale aero-derivative engine cycles based on existing and projected cycles for applications in industrial power generation, combined heat and power concept, rotating equipment driving, and/or allied processes. The investigation was done by carrying out preliminary design and performance simulation of a simple cycle (baseline two-spool small-scale aero-derivative turboshaft engine model, and some advanced counterpart aero-derivative configurations. The advanced configurations consist of recuperated and intercooled/recuperated engine cycles of same nominal power rating of 1.567 MW. The baseline model was derived from the conversion of an existing helicopter engine model. In doing so, design point and off-design point performances of the engine models were established. In comparing their performances, it was observed that to a large extent, the advanced engine cycles showed superior performance in terms of thermal efficiency, and specific fuel consumption. In numerical terms, thermal efficiencies of recuperated engine cycle, and intercooled/recuperated engine cycles, over the simple cycle at DP increased by 13.5%, and 14.5% respectively, whereas specific fuel consumption of these cycles over simple cycle at DP decreased by 12.5%, and 13% respectively. This research relied on open access public literature for data.

  12. Synthesis gas solubility in Fischer-Tropsch slurry: Final report

    Energy Technology Data Exchange (ETDEWEB)

    Chao, K.C.; Lin, H.M.

    1988-01-01

    The objective is to investigate the phase equilibrium behavior of synthesis gases and products in a Fischer-Tropsch slurry reactor. A semi-flow apparatus has been designed and constructed for this purpose. Measurements have been made for hydrogen, cabon monoxide, methane, ethane, ethylene, and carbon dioxide in a heavy n-paraffin at temperatures from 100 to 300)degree)C and pressures 10 to 50 atm. Three n-paraffin waxes: n-eicosane (n-C/sub 20/), n-octacosane )n-C/sub 28/), and n-hexatriacontane (n-C/sub 36/), were studied to model the industrial wax. Solubility of synthesis gas mixtures of H/sub 2/ and CO in n-C/sub 28/ was also determined at two temperatures (200 and 300)degree)C) for each of three gas compositions (40.01, 50.01, and 66.64 mol%) of hydrogen). Measurements were extended to investigate the gas solubility in two industrial Fischer-Tropsch waxes: Mobilwax and SASOL wax. Observed solubility increases in the order: H/sub 2/, CO, CH/sub 4/, CO/sub 2/, C/sub 2/H/sub 4/, C/sub 2/H/sub 6/, at a given temperature pressure, and in the same solvent. Solubility increases with increasing pressure for all the gases. Lighter gases H/sub 2/ and CO show increased solubility with increasing temperature, while the heavier gases CO/sub 2/, ethane, and ethylene show decreased solubility with increasing temperature. The solubility of methane, the intermediate gas, changes little with temperature, and shows a shallow minimum at about 200)degrees)C or somewhat above. Henry's constant and partial molal volume of the gas solute at infinite dilution are determinedfrom the gas solubility data. A correlation is developed from the experimental data in the form on an equation of state. A computer program has been prepared to implement the correlation. 19 refs., 66 figs., 39 tabs.

  13. Synthesis of [13C6]-labelled phenethylamine derivatives for drug quantification in biological samples.

    Science.gov (United States)

    Karlsen, Morten; Liu, HuiLing; Berg, Thomas; Johansen, Jon Eigill; Hoff, Bård Helge

    2014-05-15

    The availability of high-quality (13)C-labelled internal standards will improve accurate quantification of narcotics and drugs in biological samples. Thus, the synthesis of 10 [(13)C6]-labelled phenethylamine derivatives, namely amphetamine, methamphetamine, 3,4-methylenedioxyamphetamine, 3,4-methylenedioxymethamphetamine, 3,4-methylenedioxy-N-ethylamphetamine, 4-methoxyamphetamine, 4-methoxymethamphetamine, 3,5-dimethoxyphenethylamine 4-bromo-2,5-dimethoxyphenethylamine and 2,5-dimethoxy-4-iodophenethylamine, have been undertaken. [(13)C6]-Phenol proved to be an excellent starting material for making (13)C-labelled narcotic substances in the phenethylamine class, and a developed Stille-type coupling enabled an efficient synthesis of the 3,4-methylenedioxy and 4-methoxy derivatives. The pros and cons of alternative routes and transformations are also discussed. The [(13)C6]-labelled compounds are intended for use as internal standards in forensic analysis, health sciences and metabolomics studies by gas chromatography-mass spectrometry and liquid chromatography-tandem mass spectrometry. Copyright © 2014 John Wiley & Sons, Ltd.

  14. Efficient synthesis of a fluorine-18 labeled biotin derivative.

    Science.gov (United States)

    Claesener, Michael; Breyholz, Hans-Jörg; Hermann, Sven; Faust, Andreas; Wagner, Stefan; Schober, Otmar; Schäfers, Michael; Kopka, Klaus

    2012-11-01

    The natural occurring vitamin biotin, also known as vitamin H or vitamin B(7), plays a major role in various metabolic reactions. Caused by its high binding affinity to the protein avidin with a dissociation constant of about 10(-15)M the biotin-avidin system was extensively examined for multiple applications. We have synthesized a fluorine-18 labeled biotin derivative [(18)F]4 for a potential application in positron emission tomography (PET). Mesylate precursor 3 was obtained by an efficient two-step reaction via a copper catalyzed azide-alkyne cycloaddition (CuAAC) from easily accessible starting materials. [(18)F]4 was successfully synthesized by a nucleophilic radiofluorination of precursor 3. A biodistribution study by means of small-animal PET imaging in wt-mice was performed and serum stability was examined. Compound [(18)F]4 was obtained from precursor compound 3 with an average specific activity of 16GBq/μmol within 45min and a radiochemical yield of 45±5% (decay corrected). [(18)F]4 demonstrated only negligible decomposition in human serum. A qualitative binding study revealed the high affinity of the synthesized biotin derivative to avidin. Blocking experiments with native biotin showed that binding was site-specific. Biodistribution studies showed that [(18)F]4 was cleared quickly and efficiently from the body by hepatobiliary and renal elimination. An efficient synthesis for [(18)F]4 was established. In vivo characteristics were determined and demonstrated the pharmacokinetic behaviour of [(18)F]4. Copyright © 2012 Elsevier Inc. All rights reserved.

  15. Gas-phase synthesis of magnetic metal/polymer nanocomposites

    Science.gov (United States)

    Starsich, Fabian H. L.; Hirt, Ann M.; Stark, Wendelin J.; Grass, Robert N.

    2014-12-01

    Highly magnetic metal Co nanoparticles were produced via reducing flame spray pyrolysis, and directly coated with an epoxy polymer in flight. The polymer content in the samples varied between 14 and 56 wt% of nominal content. A homogenous dispersion of Co nanoparticles in the resulting nanocomposites was visualized by electron microscopy. The size and crystallinity of the metallic fillers was not affected by the polymer, as shown by XRD and magnetic hysteresis measurements. The good control of the polymer content in the product nanocomposite was shown by elemental analysis. Further, the successful polymerization in the gas phase was demonstrated by electron microscopy and size measurements. The presented effective, dry and scalable one-step synthesis method for highly magnetic metal nanoparticle/polymer composites presented here may drastically decrease production costs and increase industrial yields.

  16. The Interpretation of Cholesterol Balance Derived Synthesis Data and Surrogate Noncholesterol Plasma Markers for Cholesterol Synthesis under Lipid Lowering Therapies

    Directory of Open Access Journals (Sweden)

    Frans Stellaard

    2017-01-01

    Full Text Available The cholesterol balance procedure allows the calculation of cholesterol synthesis based on the assumption that loss of endogenous cholesterol via fecal excretion and bile acid synthesis is compensated by de novo synthesis. Under ezetimibe therapy hepatic cholesterol is diminished which can be compensated by hepatic de novo synthesis and hepatic extraction of plasma cholesterol. The plasma lathosterol concentration corrected for total cholesterol concentration (R_Lath as a marker of de novo cholesterol synthesis is increased during ezetimibe treatment but unchanged under treatment with ezetimibe and simvastatin. Cholesterol balance derived synthesis data increase during both therapies. We hypothesize the following. (1 The cholesterol balance data must be applied to the hepatobiliary cholesterol pool. (2 The calculated cholesterol synthesis value is the sum of hepatic de novo synthesis and the net plasma—liver cholesterol exchange rate. (3 The reduced rate of biliary cholesterol absorption is the major trigger for the regulation of hepatic cholesterol metabolism under ezetimibe treatment. Supportive experimental and literature data are presented that describe changes of cholesterol fluxes under ezetimibe, statin, and combined treatments in omnivores and vegans, link plasma R_Lath to liver function, and define hepatic de novo synthesis as target for regulation of synthesis. An ezetimibe dependent direct hepatic drug effect cannot be excluded.

  17. Gas-phase synthesis of semiconductor nanocrystals and its applications

    Science.gov (United States)

    Mandal, Rajib

    Luminescent nanomaterials is a newly emerging field that provides challenges not only to fundamental research but also to innovative technology in several areas such as electronics, photonics, nanotechnology, display, lighting, biomedical engineering and environmental control. These nanomaterials come in various forms, shapes and comprises of semiconductors, metals, oxides, and inorganic and organic polymers. Most importantly, these luminescent nanomaterials can have different properties owing to their size as compared to their bulk counterparts. Here we describe the use of plasmas in synthesis, modification, and deposition of semiconductor nanomaterials for luminescence applications. Nanocrystalline silicon is widely known as an efficient and tunable optical emitter and is attracting great interest for applications in several areas. To date, however, luminescent silicon nanocrystals (NCs) have been used exclusively in traditional rigid devices. For the field to advance towards new and versatile applications for nanocrystal-based devices, there is a need to investigate whether these NCs can be used in flexible and stretchable devices. We show how the optical and structural/morphological properties of plasma-synthesized silicon nanocrystals (Si NCs) change when they are deposited on stretchable substrates made of polydimethylsiloxane (PDMS). Synthesis of these NCs was performed in a nonthermal, low-pressure gas phase plasma reactor. To our knowledge, this is the first demonstration of direct deposition of NCs onto stretchable substrates. Additionally, in order to prevent oxidation and enhance the luminescence properties, a silicon nitride shell was grown around Si NCs. We have demonstrated surface nitridation of Si NCs in a single step process using non?thermal plasma in several schemes including a novel dual-plasma synthesis/shell growth process. These coated NCs exhibit SiNx shells with composition depending on process parameters. While measurements including

  18. High School Forum. The Solution: "Derivation of the Ideal Gas Law."

    Science.gov (United States)

    Herron, J. Dudley, Ed.

    1980-01-01

    Presents responses to an earlier report concerning a procedure for the derivation of the Ideal Gas Law from Charles', Boyle's, and other gas laws. Logic errors and solutions that work are discussed. (CS)

  19. Synthesis of pyrimidine carboxamide derivatives catalyzed by uranyl

    African Journals Online (AJOL)

    2014-09-02

    (Received September 2, 2014; revised January 1, 2016). ABSTRACT. An efficient and simple method was developed for the synthesis pyrimidine-5-carboxamides using. UO2(NO3)2.6H2O catalyst under conventional and microwave irradiation. The synthesis of dihydropyrimidine using uranyl nitrate had shown many ...

  20. Biological relevance and synthesis of C-substituted morpholine derivatives

    NARCIS (Netherlands)

    Wijtmans, R.; Vink, M.K.S.; Schoemaker, H.E.; Delft, F.L. van; Blaauw, R.H.; Rutjes, F.P.J.T.

    2004-01-01

    C-Functionalized morpholines are found in a variety of natural products and biologically active compounds, but have also for other reasons been applied in organic synthesis. This review deals with the biological relevance of C-substituted morpholines, their synthesis and important applications in

  1. Multistep Synthesis of a Terphenyl Derivative Showcasing the Diels-Alder Reaction

    Science.gov (United States)

    Davie, Elizabeth A. Colby

    2015-01-01

    An adaptable multistep synthesis project designed for the culmination of a second-year organic chemistry laboratory course is described. The target compound is a terphenyl derivative that is an intermediate in the synthesis of compounds used in organic light-emitting devices. Students react a conjugated diene with dimethylacetylene dicarboxylate…

  2. Synthesis of the Insecticide Prothrin and Its Analogues from Biomass-Derived 5-(Cloromethyl)furfural

    Science.gov (United States)

    2013-12-19

    Synthesis of the Insecticide Prothrin and Its Analogues from Biomass-Derived 5‑(Chloromethyl) furfural Fei Chang,† Saikat Dutta,† James J. Becnel...derived platform chemical 5- (chloromethyl) furfural in six steps and overall 65% yield. Two structural analogues of prothrin were also prepared following...insecticidal activities. KEYWORDS: biomass, furans, pyrethroids, synthesis, 5-(chloromethyl) furfural ■ INTRODUCTION Previously, we have described the

  3. a convenient synthesis of pyrandione derivatives using p

    African Journals Online (AJOL)

    N. Benosmane

    2016-09-01

    Sep 1, 2016 ... P-TOLUENESULFONIC ACID AS CATALYST UNDER ULTRASOUND ... improvement a green organic reaction methodology, which is ..... [5] Tan S F, Ang K P, Jayachandran H L. Synthesis and characterisation of copper(II),.

  4. Synthesis of novel azaxanthones derived from N-hydroxyazoles

    DEFF Research Database (Denmark)

    Kristensen, Jesper Langgaard; Vedsø, P.; Begtrup, M.

    2002-01-01

    The synthesis of a new class of azaxanthones is presented. The N-O functionality of 1-hydroxypyrazole and 1-hydroxy-1,2,3-triazole was used to direct metalation and subsequently in the new ring systems....

  5. SYNTHESIS AND CYTOTOXIC ACTIVITY OF CHALCONE DERIVATIVES ON HUMAN BREAST CANCER CELL LINES

    Directory of Open Access Journals (Sweden)

    Nuraini Harmastuti

    2012-12-01

    Full Text Available Chalcone, an α,β-unsaturated ketone, has been shown have many biological activities such as anticancer and antifungi. This research was conducted to synthesize the chalcone derivatives and to obtain their cytotoxic activity on human cervix cancer cell lines. Synthesis of chalcone and its derivatives, 4II-methylchalcone, 4II-methoxychalcone, and 3II,4II-dichlorochalcone was carried out using starting materials of benzaldehide and acetofenon, p-methylacetophenone, p-methoxyacetophenone, as well as m,p-dichloroacetophenone through Claisen Schmidt condensation catalized by NaOH in ethanol at 15 °C. The purity of synthesized compounds were analyzed by thin layer chromatography, melting range, and gas chromatography. Structure elucidations were conducted by UV spectrophotometer, IR spectrometer, 1H-NMR spectrometer, as well as mass spectrometer. Cytotoxic activities were determined by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT microculture tetrazolium viability assay. The results showed that chalcone and derivatives compounds have been able to be synthesized and purified and had the same structure as a predicted structure. Chalcone had highest cytotoxic activity compared to that of its derivatives, with the IC50 values of chalcone, 4II-methylchalcone, 4II-methoxychalcone, and 3II,4II-dichlorochalcone were 9.49, 14.79, 11.48, and 24.26 µg/mL respectively. It was concluded that methyl, methoxy as well as chlorine substitution at 3 II and 4II position decrease the cytotoxic activity of chalcone.

  6. Boron-containing catalysts for dry reforming of methane to synthesis gas

    KAUST Repository

    Takanabe, Kazuhiro; Basset, Jean-Marie; Park, Jung-Hyun; Samal, Akshaya Kumar; Alsabban, Bedour

    2018-01-01

    The present invention uses a cobalt catalyst for carbon dioxide reforming of lower alkanes to synthesis gas having a cobalt catalyst on an oxide support where the supported cobalt catalyst has been modified with a boron precursor. The boron

  7. The selective generation of acetic acid directly from synthesis gas

    International Nuclear Information System (INIS)

    Knifton, J.F.

    1986-01-01

    The authors conclude that each of the ruthenium, cobalt and iodide-containing catalyst components have very specific roles to play in the ''melt'' catalyzed conversion of synthesis gas to acetic acid. C 1 -Oxygenate formation is only observed in the presence of ruthenium carbonyls - [Ru(CO) 3 I 3 ] - is here the dominant species - and there is a direct relationship between liquid yield, ΣOAc - productivity and [Ru(CO) 3 I 3 ] - content. Controlled quantities of iodide ensure that initially formed MeOH is rapidly converted to the more reactive methyl iodide. Subsequent cobalt-catalyzed carbonylation to acetic acid may be preparatively attractive (>80% selectivity, good yields) relative to competing syntheses, where the [Co(CO) 4 ] - concentration is maximized that is, where the Co/Ru ratio is >1, the syngas feedstock is rich in CO, and the initial iodide/cobalt ratios are ca. unity. Formation of cobalt-iodide species appears to be a competing, inhibitory step in this catalysis

  8. Bendable Zeolite Membranes: Synthesis and Improved Gas Separation Performance.

    Science.gov (United States)

    Wang, Bo; Ho, W S Winston; Figueroa, Jose D; Dutta, Prabir K

    2015-06-23

    Separation and sequestration of CO2 emitted from fossil energy fueled electric generating units and industrial facilities will help in reducing anthropogenic CO2, thereby mitigating its adverse climate change effects. Membrane-based gas separation has the potential to meet the technical challenges of CO2 separation if high selectivity and permeance with low costs for large-scale manufacture are realized. Inorganic zeolite membranes in principle can have selectivity and permeance considerably higher than polymers. This paper presents a strategy for zeolite growth within the pores of a polymer support, with crystallization time of an hour. With a thin coating of 200-300 nm polydimethylsiloxane (PDMS) on the zeolite-polymer composite, transport data for CO2/N2 separation indicate separation factors of 35-45, with CO2 permeance between 1600 and 2200 GPU (1 GPU = 3.35 × 10(-10) mol/(m(2) s Pa)) using dry synthetic mixtures of CO2 and N2 at 25 °C. The synthesis process results in membranes that are highly reproducible toward transport measurements and exhibit long-term stability (3 days). Most importantly, these membranes because of the zeolite growth within the polymer support, as contrasted to conventional zeolite growth on top of a support, are mechanically flexible.

  9. Metabolic modeling of synthesis gas fermentation in bubble column reactors.

    Science.gov (United States)

    Chen, Jin; Gomez, Jose A; Höffner, Kai; Barton, Paul I; Henson, Michael A

    2015-01-01

    A promising route to renewable liquid fuels and chemicals is the fermentation of synthesis gas (syngas) streams to synthesize desired products such as ethanol and 2,3-butanediol. While commercial development of syngas fermentation technology is underway, an unmet need is the development of integrated metabolic and transport models for industrially relevant syngas bubble column reactors. We developed and evaluated a spatiotemporal metabolic model for bubble column reactors with the syngas fermenting bacterium Clostridium ljungdahlii as the microbial catalyst. Our modeling approach involved combining a genome-scale reconstruction of C. ljungdahlii metabolism with multiphase transport equations that govern convective and dispersive processes within the spatially varying column. The reactor model was spatially discretized to yield a large set of ordinary differential equations (ODEs) in time with embedded linear programs (LPs) and solved using the MATLAB based code DFBAlab. Simulations were performed to analyze the effects of important process and cellular parameters on key measures of reactor performance including ethanol titer, ethanol-to-acetate ratio, and CO and H2 conversions. Our computational study demonstrated that mathematical modeling provides a complementary tool to experimentation for understanding, predicting, and optimizing syngas fermentation reactors. These model predictions could guide future cellular and process engineering efforts aimed at alleviating bottlenecks to biochemical production in syngas bubble column reactors.

  10. Synthesis gas demonstration plant program, Phase I. Site confirmation report

    Energy Technology Data Exchange (ETDEWEB)

    1978-12-01

    With few reservations, the Baskett, Kentucky site exhibits the necessary characteristics to suggest compatibility with the proposed Synthesis Gas Demonstration Plant Project. An evaluation of a broad range of technical disciplinary criteria in consideration of presently available information indicated generally favorable conditions or, at least, conditions which could be feasibly accommodated in project design. The proximity of the Baskett site to market areas and sources of raw materials as well as a variety of transportation facilities suggests an overall favorable impact on Project economic feasibility. Two aspects of environmental engineering, however, have been identified as areas where the completion or continuation of current studies are required before removing all conditions on site suitability. The first aspect involves the current contradictory status of existing land use and planning ordinances in the site area. Additional investigation of the legality of, and local attitudes toward, these present plans is warranted. Secondly, terrestrial and aquatic surveys of plant and animal life species in the site area must be completed on a seasonal basis to confirm the preliminary conclusion that no exclusionary conditions exist.

  11. Synthesis and anticancer evaluation of imidazolinone and benzoxazole derivatives

    Directory of Open Access Journals (Sweden)

    Heba A. El-Hady

    2017-05-01

    Full Text Available A series of imidazolinone and benzoxazole derivatives (3 and 5 have been synthesized by the condensation of oxazolinone derivatives (2a–c with aniline and 2-hydroxyaniline. Acetyl derivatives (4, 6 and 7 were prepared via acetylation of compounds 3 and 5 with acetic anhydride and chloroacetyl chloride. The results revealed that imidazolinone and benzoxazole derivatives are potent against the cancer cell lines MCF-7 and HePG2. In particular, benzoxazole derivatives are more potent than imidazolinone derivatives.

  12. Equipment Design and Cost Estimation for Small Modular Biomass Systems, Synthesis Gas Cleanup, and Oxygen Separation Equipment; Task 9: Mixed Alcohols From Syngas -- State of Technology

    Energy Technology Data Exchange (ETDEWEB)

    Nexant Inc.

    2006-05-01

    This deliverable is for Task 9, Mixed Alcohols from Syngas: State of Technology, as part of National Renewable Energy Laboratory (NREL) Award ACO-5-44027, ''Equipment Design and Cost Estimation for Small Modular Biomass Systems, Synthesis Gas Cleanup and Oxygen Separation Equipment''. Task 9 supplements the work previously done by NREL in the mixed alcohols section of the 2003 technical report Preliminary Screening--Technical and Economic Assessment of Synthesis Gas to Fuels and Chemicals with Emphasis on the Potential for Biomass-Derived Syngas.

  13. Ion transport membrane reactor systems and methods for producing synthesis gas

    Science.gov (United States)

    Repasky, John Michael

    2015-05-12

    Embodiments of the present invention provide cost-effective systems and methods for producing a synthesis gas product using a steam reformer system and an ion transport membrane (ITM) reactor having multiple stages, without requiring inter-stage reactant injections. Embodiments of the present invention also provide techniques for compensating for membrane performance degradation and other changes in system operating conditions that negatively affect synthesis gas production.

  14. Gold-Catalyzed Cyclizations of Alkynol-Based Compounds: Synthesis of Natural Products and Derivatives

    Directory of Open Access Journals (Sweden)

    Pedro Almendros

    2011-09-01

    Full Text Available The last decade has witnessed dramatic growth in the number of reactions catalyzed by gold complexes because of their powerful soft Lewis acid nature. In particular, the gold-catalyzed activation of propargylic compounds has progressively emerged in recent years. Some of these gold-catalyzed reactions in alkynes have been optimized and show significant utility in organic synthesis. Thus, apart from significant methodology work, in the meantime gold-catalyzed cyclizations in alkynol derivatives have become an efficient tool in total synthesis. However, there is a lack of specific review articles covering the joined importance of both gold salts and alkynol-based compounds for the synthesis of natural products and derivatives. The aim of this Review is to survey the chemistry of alkynol derivatives under gold-catalyzed cyclization conditions and its utility in total synthesis, concentrating on the advances that have been made in the last decade, and in particular in the last quinquennium.

  15. Synthesis of Substituted α-Trifluoromethyl Piperidinic Derivatives

    Directory of Open Access Journals (Sweden)

    Sarah Rioton

    2017-03-01

    Full Text Available A comprehensive survey of pathways leading to the generation of α-trifluoromethyl monocyclic piperidinic derivatives is provided (65 references. These compounds have been synthesized either from 6-membered rings e.g., pipecolic acid or lactam derivatives by introduction a trifluoromethyl group, from pyridine or pyridinone derivatives by reduction, and from 5-membered rings e.g., prolinol derivatives by ring expansion, from linear amines by cyclization or from dienes/dienophiles by [4 + 2]-cycloaddition.

  16. Synthesis of octahedral like Cu-BTC derivatives derived from MOF calcined under different atmosphere for application in CO oxidation

    Science.gov (United States)

    Yang, Yiqiong; Dong, Han; Wang, Yin; He, Chi; Wang, Yuxin; Zhang, Xiaodong

    2018-02-01

    A series of octahedral structure Cu-BTC derivatives were successfully achieved through direct calcination of copper based metal organic framework Cu-BTC under different atmosphere (CO reaction gas, oxidizing gas O2, reducing gas H2, inert gas Ar). The Cu-BTC derivatives were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), laser Raman spectroscopy (LRS), N2 adsorption-desorption isotherm, element analysis, H2-temperature program reduction (H2-TPR) and X-ray photoelectron spectroscopic (XPS). It is found that Cu-BTC derivative derived from MOF calcined under reaction gas/O2 (Cu-BTC-CO/Cu-BTC-O) only retain Cu2O and CuO species. In addition, a weak Cu-BTC structure and Cu particles were observed on Cu-BTC derivative derived from MOF calcined under H2 (Cu-BTC-H). Obviously differently, Cu-BTC derivative derived from MOF calcined under Ar (Cu-BTC-Ar) still retains good MOF structure. The catalytic performance for CO oxidation over Cu-BTC derivatives was studied. It was found that Cu-BTC-CO showed a smaller specific surface area (8.0 m2/g), but presented an excellent catalytic performance, long-term stability and cycling stability with a complete CO conversion temperature (T100) of 140 °C, which was ascribed to the higher Cu2O/CuO ratio, good low temperature reduction behavior and a high quantity of surface active oxygen species.

  17. An exploration on the synthesis and bio-applications of derivatives ...

    African Journals Online (AJOL)

    Keeping in view of the importance of this organic moiety in the field of medicine and biology here an attempt has been made to review the synthesis and biological importance of heterocyclic Mannich base derivatives. Keywords: Amines, β-amino carbonyl compounds, Biological activity, Heterocyclic Mannich base derivative ...

  18. Synthesis and Antiangiogenic Activity of N-Alkylated Levamisole Derivatives

    DEFF Research Database (Denmark)

    Hansen, Anders N.; Bendiksen, Christine D.; Sylvest, Lene

    2012-01-01

    profile, was recently shown to be an inhibitor of angiogenesis in vitro and exhibited tumor growth inhibition in mice. Here we describe the synthesis and in vitro evaluation of a series of N-alkylated analogues of levamisole with the aim of characterizing structure-activity relationships with regard...

  19. Titanium(III) chloride mediated synthesis of furan derivatives ...

    Indian Academy of Sciences (India)

    Administrator

    a radical-induced synthesis of substituted furans from α-bromo-β-keto enoleth- ers using tributyl tinhydride (TBTH) as the radical initiator with 35–69% yield. But the use of tin com- pounds has certain limitations due to their toxicity and difficulties in isolation of pure products free of tin residues. To overcome these difficulties ...

  20. A facile approach for the synthesis of indenoimidazole derivatives ...

    Indian Academy of Sciences (India)

    J. Chem. Sci. Vol. 128, No. 12, December 2016, pp. 1841–1847. c Indian Academy of Sciences. DOI 10.1007/s12039-016-1181-2. A facile approach for the synthesis of ... pounds 1 and 2 are presented here in terms of crystal engineering and supramolecular chemistry. ... zoles are heterocyclic organic compounds of wide.

  1. Synthesis and antibacterial activity of sulfonamide derivatives at C-8 ...

    Indian Academy of Sciences (India)

    showed higher antibacterial activity compared with standard drug ampicillin. Keywords. Synthesis ... factor-kB regulated gene products leading to potenti- ation of ... constituent of CNSL natural source to evaluate their biological activity by ... Analytical thin layer ..... cially available CNSL by a reported method.26 Accord-.

  2. The synthesis and biological activity of some bile acid derivatives

    International Nuclear Information System (INIS)

    Kadirov, A.Kh.; Khaydarov, K.Kh.; Giyosov, A.Sh.

    2000-01-01

    In this monograph authors present the modified technologic scheme of receiving of 3α, 7α, 12α-three hydro xi cholanic acid with using of available raw materials for the synthesis products and for receiving on its base drugs diluent cholesterol gallstones of gall-bladder and bile-ducts

  3. Research in Korea on Gas Phase Synthesis and Control of Nanoparticles

    International Nuclear Information System (INIS)

    Choi, Mansoo

    2001-01-01

    Research activity into the gas phase synthesis of nanoparticles has witnessed rapid growth on a worldwide basis, which is also reflected by Korean research efforts. Nanoparticle research is inherently a multi-disciplinary activity involving both science and engineering. In this paper, the recent studies undertaken in Korea on the gas phase synthesis and control of nanoparticles are reviewed. Studies on the synthesis of various kinds of nanoparticles are first discussed with a focus on the different types of reactors used. Recent experimental and theoretical studies and newly developed methods of measuring and modeling nanoparticle growth are also reviewed

  4. Design and Synthesis of a Novel Class of Flavonoid Derivatives via Sequential Phosphorylation and its Application for Greener Nanoparticle Synthesis

    Science.gov (United States)

    Osonga, Francis Juma

    Flavonoids exhibit arrays of biological effects that are beneficial to humans, including anti-viral, anti-oxidative, anti-inflammatory and anti-carcinogenic effects. However, these applications have been hindered by their poor stability and solubility in common solvents. Consequently, there is significant interest in the modification of flavonoids to improve their solubility. This poor solubility is also believed to be responsible for its permeability and bioavailability. Hence the central goal of this work is to design synthetic strategies for the sequential protection of the -OH groups in order to produce phosphorylated quercetin and apigenin derivatives. This work is divided into two parts: the first part presents the design, synthesis, and characterization of novel flavonoid derivatives via global and sequential phosphorylation. The second part focuses on the application of the synthesized derivatives for greener nanoparticle synthesis. This work shows for the first time that sequential phosphorylation of Quercetin is feasible through the design of 4 new derivatives namely: 5,4'-O-Quercetin Diphosphate (QDPI), 4'-O-phosphate Quercetin (4'-QPI), 5,4'-Quercetin Diphosphate (5,4'-QDP) and monophosphate 4-QP. The synthesis of 4'-QP and 5, 4'-QDP was successful with 85% and 60.5% yields respectively. In addition, the progress towards the total synthesis of apigenin phosphate derivatives (7, 4'-ADP and 7-AP) is presented. The synthesized derivatives were characterized using 1H, 13C, and 31P NMR. The phosphorylated derivatives were subsequently explored as reducing agents for sustainable synthesis of gold, silver and copper nanoparticles. We have successfully demonstrated the photochemical synthesis of gold nanoplates of sizes ranging from 10 - 200 nm using water soluble QDP in the presence of sunlight. This work contributes immensely in promoting the ideals of green nanosynthesis by (i) eliminating the use of organic solvents in the nanosynthesis, (ii) exploiting the

  5. Studies on Synthesis of Pyrimidine Derivatives and their Pharmacological Evaluation

    Directory of Open Access Journals (Sweden)

    T. A. Naik

    2007-01-01

    Full Text Available 1,3,4-Oxadiazoles were associated with broad spectrum of biological activities including antituberculosis, anticonvulsant, anti-inflammatory, insecticidal, antifungal, analgesic and antitumor properties. Morpholine derivatives find their wide spectrum of antimicrobial activity and exhibit anthelmintic, bactericidal and insecticidal activity. Pyrimidine derivatives are also reported to possess antibacterial, antimicrobial, antifungal, anticancer and anticonvulsant activities. Encouraged by this observations we decided to synthesised novel pyrimidine derivatives.

  6. Synthesis and Antibacterial Screening of Novel Derivatives of Embelin

    Science.gov (United States)

    Subramanian, L.; Leema, M.; Pradeep, N. S.; Joy, B.; Pillai, Z. S.

    2018-02-01

    Embelin, a naturally occurring compound extracted from Embelia ribes is used in Ayurvedic system of medicine owing to its wide spectrum of biological activities. In the present work, we have aimed at improving the efficacy of Embelin by appropriate structural modifications. A few novel derivatives of Embelin have been prepared. The antibacterial screening of these derivatives were carried out and compared with a well known antibiotic, Streptomycin. The derivatives exhibited better activity than Streptomycin and the lead molecule, Embelin.

  7. Gas-Phase Combustion Synthesis of Aluminum Nitride Powder

    Science.gov (United States)

    Axelbaum, R. L.; Lottes, C. R.; Huertas, J. I.; Rosen, L. J.

    1996-01-01

    Due to its combined properties of high electrical resistivity and high thermal conductivity aluminum nitride (AlN) is a highly desirable material for electronics applications. Methods are being sought for synthesis of unagglomerated, nanometer-sized powders of this material, prepared in such a way that they can be consolidated into solid compacts having minimal oxygen content. A procedure for synthesizing these powders through gas-phase combustion is described. This novel approach involves reacting AlCl3, NH3, and Na vapors. Equilibrium thermodynamic calculations show that 100% yields can be obtained for these reactants with the products being AlN, NaCl, and H2. The NaCl by-product is used to coat the AlN particles in situ. The coating allows for control of AlN agglomeration and protects the powders from hydrolysis during post-flame handling. On the basis of thermodynamic and kinetic considerations, two different approaches were employed to produce the powder, in co-flow diffusion flame configurations. In the first approach, the three reactants were supplied in separate streams. In the second, the AlCl3 and NH3 were premixed with HCl and then reacted with Na vapor. X-ray diffraction (XRD) spectra of as-produced powders show only NaCl for the first case and NaCl and AlN for the second. After annealing at 775 C tinder dynamic vacuum, the salt was removed and XRD spectra of powders from both approaches show only AlN. Aluminum metal was also produced in the co-flow flame by reacting AlCl3 with Na. XRD spectra of as-produced powders show the products to be only NaCl and elemental aluminum.

  8. synthesis and characterization of some poly functionalized heterocyclic derivatives of expected biological activity

    International Nuclear Information System (INIS)

    El-sayed, M.S.

    2001-01-01

    The present work was aimed and designed to fulfil The following objectives : 1- Continuation of the effort done by our research group in the field of chemistry of pyridinethione derivatives and their biological activities. 2- Synthesis of several new heterocyclic derivatives containing N and/or S using the laboratory available reagents. 3- Establishment of the structures of the newly synthesized heterocyclic compounds by the data of IR, 1 H-NMR, mass spectra in addition to the elemental analysis. 4- Synthesis of some of these heterocyclic derivatives via alternative routs and this used as a tool to confirm the structures of the newly synthesized heterocyclic derivatives. 5- study of the most probable mechanisms leading to the formation of the new heterocyclic derivatives. 6- The antimicrobial activity of some of the newly synthesized heterocyclic derivatives was tested against several types of organisms

  9. Synthesis and characterization of new polyamides derived from alanine and valine derivatives

    Directory of Open Access Journals (Sweden)

    El-Faham Ayman

    2012-11-01

    Full Text Available Abstract Background Many efforts have been recently devoted to design, investigate and synthesize biocompatible, biodegradable polymers for applications in medicine for either the fabrication of biodegradable devices or as drug delivery systems. Many of them consist of condensation of polymers having incorporated peptide linkages susceptible to enzymatic cleavage. Polyamides (PAs containing α-amino acid residues such as L-leucine, L-alanine and L-phenylalanine have been reported as biodegradable materials. Furthermore, polyamides (PAs derived from C10 and C14 dicarboxylic acids and amide-diamines derived from 1,6-hexanediamine or 1,12-dodecanediamine and L-phenylalanine, L-valyl-L-phenylalanine or L-phenylalanyl-L-valine residues have been reported as biocompatible polymers. We have previously described the synthesis and thermal properties of a new type of polyamides-containing amino acids based on eight new symmetric meta-oriented protected diamines derived from coupling of amino acids namely; Fomc-glycine, Fmoc-alanine, Fomc-valine and Fomc-leucine with m-phenylene diamine or 2,6-diaminopyridine. Results revealed that incorporation of pyridine onto the polymeric backbone of all series decreases the thermal stability. Here we describe another family of polyamides based on benzene dicarboxylic acid, pyridine dicarboxylic acid, and α-amino acid linked to benzidine and 4,4′-oxydianiline to study the effect of the dicarboxylic acid as well as the amino acids on the nature and thermal stability of the polymers. Results We report here the preparation of a new type of polyamides based on benzene dicarboxylic acid, pyridine dicarboxylic acid, and α-amino acid linked to benzidine and 4,4′-oxydianiline to study the effect of the dicarboxylic acid as well as the amino acids on the nature and thermal stability of polymers. The thermal properties of the polymers were evaluated by different techniques. Results revealed that structure-thermal property

  10. Microbial hydrogenogenic CO conversions: applications in synthesis gas purification and biodesulfurization

    NARCIS (Netherlands)

    Sipma, J.

    2006-01-01

    Hydrogen gas attracts great interest as a potential clean future fuel and it is an excellent electron donor in biotechnological reductive processes, e.g. in biodesulfurization. Bulk production of H 2 relies on the conversion of organic matter into synthesis gas, a mixture of H

  11. Microbial aspects of synthesis gas fed bioreactors treating sulfate and metal rich wastewaters

    NARCIS (Netherlands)

    Houten, van B.H.G.W.

    2006-01-01

    The use of synthesis gas fed sulfate-reducing bioreactors to simultaneously remove both oxidized sulfur compounds and metals shows great potential to treat wastewaters generated as a result of flue gas scrubbing, mining activities and galvanic processes. Detailed information about the phylogenetic

  12. Direct Synthesis of ESBO Derivatives-18O Labelled with Dioxirane

    Directory of Open Access Journals (Sweden)

    Stefano La Tegola

    2013-01-01

    Full Text Available This work addresses a new approach developed in our laboratory, consisting in the application of isolated dimethyldioxirane (DDO, 1a labelled with 18O for synthesis of epoxidized glyceryl linoleate (Gly-LLL, 2. We expect that this work could contribute in improving analytical methods for the determination of epoxidized soybean oil (ESBO in complex food matrices by adopting an 18O-labelled-epoxidized triacylglycerol as an internal standard.

  13. Direct Synthesis of ESBO Derivatives-18O Labelled with Dioxirane

    OpenAIRE

    La Tegola, Stefano; Annese, Cosimo; Suman, Michele; Tommasi, Immacolata; Fusco, Caterina; D'Accolti, Lucia

    2013-01-01

    This work addresses a new approach developed in our laboratory, consisting in the application of isolated dimethyldioxirane (DDO, 1a) labelled with 18O for synthesis of epoxidized glyceryl linoleate (Gly-LLL, 2). We expect that this work could contribute in improving analytical methods for the determination of epoxidized soybean oil (ESBO) in complex food matrices by adopting an 18O-labelled-epoxidized triacylglycerol as an internal standard.

  14. SYNTHESIS OF BIS-QUINOXALINE DERIVATIVES USING TONSIL ...

    African Journals Online (AJOL)

    A convenient and efficient synthesis of new bis-quinoxaline is described, involving ... the following composition (in %): SiO2: 74.5, Al2O3: 9.3, MgO: 0.4, Fe2O3: 1.3, CaO: 4.0, K2O: 0.4 and .... Tonsil clay is a nanoparticle with layered structure.

  15. Design, Synthesis, and Mechanistic Evaluation of Iron-Based Catalysis for Synthesis Gas Conversion to Fuels and Chemicals. Technical Progress Report

    International Nuclear Information System (INIS)

    Akio Ishikawa; Manuel Ojeda; Nan Yao; Enrique Iglesia

    2006-01-01

    This project extends previously discovered Fe-based catalysts to hydrogen-poor synthesis gas streams derived from coal and biomass sources. These catalysts have shown unprecedented Fischer-Tropsch synthesis rate, selectivity for feedstocks consisting of synthesis gas derived from methane. During the first reporting period, we certified a microreactor, installed required analytical equipment, and reproduced synthetic protocols and catalytic results previously reported. During the second reporting period, we prepared several Fe-based compositions for Fischer-Tropsch synthesis and tested the effects of product recycle under both subcritical and supercritical conditions. During the third and fourth reporting periods, we improved the catalysts preparation method, which led to Fe-based FT catalysts with the highest FTS reaction rates and selectivities so far reported, a finding that allowed their operation at lower temperatures and pressures with high selectivity to desired products (C 5+ , olefins). During this fifth reporting period, we have studied the effects of different promoters on catalytic performance, specifically how their sequence of addition dramatically influences the performance of these materials in the Fischer-Tropsch synthesis. The resulting procedures have been optimized to improve further upon the already unprecedented rates and C 5+ selectivities of the Fe-based catalysts that we have developed as part of this project. During this fifth reporting period, we have also continued our studies of optimal activation procedures, involving reduction and carburization of oxide precursors during the early stages of contact with synthesis gas. We have completed the analysis of the evolution of oxide, carbide, and metal phases of the active iron components during initial contact with synthesis gas using advanced synchrotron techniques based on X-ray absorption spectroscopy. We have confirmed that the Cu or Ru compensates for inhibitory effects of Zn, a surface

  16. Synthesis of derivatives of tetronic acid and pulvinic acid. Total synthesis of norbadione A

    International Nuclear Information System (INIS)

    Mallinger, A.

    2008-11-01

    When vegetables like mushrooms are contaminated by radioactive caesium 137, this radioactive caesium is associated to norbadione A, a natural pigment present in two mushroom species and which can be used as a caesium decorporation agent or maybe as protection agent against ionizing radiations. Within this perspective, this research report describes the biosynthesis and the structure and properties of the norbadione A and of pulvinic acids (physicochemical properties, anti-oxidizing properties). Then, it presents the various tetronic acids (3-acyl-, 3-alkyl-, 3-alkoxy-, 3-aryl-tetronic acids and non 3-substituted tetronic acids), their synthesis path as they are described in the literature, and presents a new synthesis approach using a tandem reaction (with different esters or hydroxy esters) and the synthesis of tetronic acids. The author also proposes a new synthesis way for methyl pulvinates, and finally reports the work on the development of a total synthesis of the norbadione A

  17. Synthesis and Antimicrobial Activities of Some Novel Quinoxalinone Derivatives

    Directory of Open Access Journals (Sweden)

    Y. A. Ammar

    2000-06-01

    Full Text Available Condensation of 4-benzoyl-1,2-phenylenediamine with sodium pyruvate in acetic acid furnished two products which were identified as 6-benzoyl and 7-benzoyl-3-methyl-2(1Hquinoxalinones (1a,b. Fusion of 1a with aromatic aldehydes furnished the styryl derivatives 2a-c. Alkylation of 1a,b with dimethyl sulphate or ethyl chloroacetate produced the N-alkyl derivatives 3a,b and 4a,b. Hydrazinolysis of the ester derivative 4a with hydrazine hydrate afforded the hydrazide derivative 5 which underwent condensation with aldehydes to give the corresponding hydrazone derivatives 6a,b. In addition, chlorination of 1a with thionyl chloride afforded the 2-chloro derivative 7 which was subjected to reaction with sodium azide and n-butylamine to yield the corresponding tetrazolo (8 and n-butylamino (9 derivatives, respectively. The structures of the compounds prepared were confirmed by analytical and spectral data. Also, some of the synthesized compounds were screened for antimicrobial activity.

  18. Synthesis of substituted 1-metallyl derivatives of o- and m-carboranes and some their transformations

    International Nuclear Information System (INIS)

    Kovredov, A.I.; Shemyakin, N.F.; Zakharkin, L.I.

    1985-01-01

    Synthesis of 1-metallyl substituted o- and m- carbonates is carried out, and alkylation of benzene by them is investigated. Synthesis with 30-95% yield has been carried out by the reaction of lithium derivatives with metallylchloride in the ester-benzene solution. The reaction of benzene alkylation is studied in the presence of aluminium chloride and H 2 SO 4 . Reaction mechanisms are considered

  19. Molecular design, synthesis and physical properties of novel Cytisine-derivatives - Experimental and theoretical study

    Science.gov (United States)

    Ivanova, Bojidarka; Spiteller, Michael

    2013-02-01

    The paper presented a comprehensive theoretical and experimental study on the molecular drugs-design, synthesis, isolation, physical spectroscopic and mass spectrometric elucidation of novel functionalization derivatives of Cytisine (Cyt), using nucleosidic residues. Since these alkaloids have established biochemical profile, related the binding affinity of the nicotinic acetylcholine receptors (nAChRs), particularly α7 sub-type, the presented correlation between the molecular structure and properties allowed to evaluated the highlights of the biochemical hypothesises related the Schizophrenia. The anticancer activity of α7 subtype agonists and the crucial role of the nucleoside-based medications in the cancer therapy provided opportunity for further study on the biochemical relationship between Schizophrenia and few kinds of cancers, which has been hypothesized recently. The physical electronic absorptions (EAs), circular dichroic (CD) and Raman spectroscopic (RS) properties as well as mass spectrometric (MS) data, obtained using electrospray ionization (ESI) and atmospheric-pressure chemical ionization (APCI) methods under the positive single (MS) and tandem (MS/MS) modes of operation are discussed. Taking into account reports on a fatal intoxication of Cyt, the presented data would be of interest in the field of forensic chemistry, through development of highly selective and sensitive analytical protocols. Quantum chemical method is used to predict the physical properties of the isolated alkaloids, their affinity to the receptor loop and gas-phase stabilized species, observed mass spectrometrically.

  20. Techno-economic analysis for the evaluation of three UCG synthesis gas end use approaches

    Science.gov (United States)

    Nakaten, Natalie; Kempka, Thomas; Burchart-Korol, Dorota; Krawczyk, Piotr; Kapusta, Krzysztof; Stańczyk, Krzysztof

    2016-04-01

    Underground coal gasification (UCG) enables the utilization of coal reserves that are economically not exploitable because of complex geological boundary conditions. In the present study we investigate UCG as a potential economic approach for conversion of deep-seated coals into a synthesis gas and its application within three different utilization options. Related to geological boundary conditions and the chosen gasification agent, UCG synthesis gas composes of varying methane, hydrogen, nitrogen, carbon monoxide and carbon dioxide amounts. In accordance to its calorific value, the processed UCG synthesis gas can be utilized in different manners, as for electricity generation in a combined cycle power plant or for feedstock production making use of its various chemical components. In the present study we analyze UCG synthesis gas utilization economics in the context of clean electricity generation with an integrated carbon capture and storage process (CCS) as well as synthetic fuel and fertilizer production (Kempka et al., 2010) based on a gas composition achieved during an in situ UCG trial in the Wieczorek Mine. Hereby, we also consider chemical feedstock production in order to mitigate CO2 emissions. Within a sensitivity analysis of UCG synthesis gas calorific value variations, we produce a range of capital and operational expenditure bandwidths that allow for an economic assessment of different synthesis gas end use approaches. To carry out the integrated techno-economic assessment of the coupled systems and the sensitivity analysis, we adapted the techno-economic UCG-CCS model developed by Nakaten et al. (2014). Our techno-economic modeling results demonstrate that the calorific value has a high impact on the economics of UCG synthesis gas utilization. In the underlying study, the synthesis gas is not suitable for an economic competitive electricity generation, due to the relatively low calorific value of 4.5 MJ/Nm³. To be a profitable option for electricity

  1. Synthesis and Antimicrobial Activity of Some New Formazan Derivatives

    Directory of Open Access Journals (Sweden)

    S. I. Marjadi

    2009-01-01

    Full Text Available A series of new substituted formazan derivatives has been synthesized from corresponding aryl diazonium chloride and Schiff base in pyridine. The synthesized compounds were identified by spectral studies and screened for their antimicrobial activities.

  2. Synthesis, characterization and antibacterial activity of new fluorescent chitosan derivatives

    Czech Academy of Sciences Publication Activity Database

    Přichystalová, H.; Almonasy, N.; Abdel-Mohsen, A. M.; Abdel-Rahman, R. M.; Fouda, M. M. G.; Vojtova, L.; Kobera, Libor; Spotz, Z.; Burgert, L.; Jancar, J.

    2014-01-01

    Roč. 65, April (2014), s. 234-240 ISSN 0141-8130 Institutional support: RVO:61389013 Keywords : chitosan derivatives * fluorescence * antibacterial activity Subject RIV: CD - Macromolecular Chemistry Impact factor: 2.858, year: 2014

  3. Synthesis of some new derivatives of thiazolopyrimidines and ...

    Indian Academy of Sciences (India)

    In addition, a new series of thiazole-fused pyrimidines were synthesized and hydrolysis of one of its arylidene derivative studied. ..... ondary amines like morpholine, piperidine and pyrro- ..... Biginelli one pot cyclo-condensation reaction.21 The.

  4. Synthesis of ruthenium (III) complexes with benzimidazole derivatives

    International Nuclear Information System (INIS)

    Vyas, P.C.; Chahar, Yogesh K.; Garg, Yajula; Seth, Gita

    2003-01-01

    Complexes of ruthenium with biologically important benzimidazole derivatives, viz. 2-(2'-hydroxyphenyl) benzimidazole (HOPBI), 2-2'- mercaptophenyl) benzimidazole (HSPBI), 2- (2'-hydroxynaphthyl) benzimidazole (HONBI) have been synthesized and characterized. (author)

  5. Allobetulin and Its Derivatives: Synthesis and Biological Activity

    Directory of Open Access Journals (Sweden)

    Talgat S. Seitembetov

    2011-03-01

    Full Text Available This review covers the chemistry of allobetulin analogs, including their formation by rearrangement from betulin derivatives, their further derivatisation, their fusion with heterocyclic rings, and any further rearrangements of allobetulin compounds including ring opening, ring contraction and ring expansion reactions. In the last part, the most important biological activities of allobetulin derivatives are listed. One hundred and fifteen references are cited and the relevant literature is covered, starting in 1922 up to the end of 2010.

  6. Synthesis and Antibacterial Activities of New Metronidazole and Imidazole Derivatives

    Directory of Open Access Journals (Sweden)

    Abdul Jabar Kh. Atia

    2009-07-01

    Full Text Available New imidazole ring derivatives comprising 1,3-oxazoline, Schiff's bases, thiadiazole, oxadiazole and 1,2,4-triazole moieties are reported. 3-Aminobiimidazol-4-one compounds 7a-c were synthesized by the reaction of compounds 6a-c with hydrazine hydrate. Biimidazole esters 9a-c were converted into biimidazole hydrazide esters 10a-c. Compounds 7a-c and 10a-c were converted into a variety of derivatives.

  7. Controlled synthesis of the tricontinuous mesoporous material IBN-9 and its carbon and platinum derivatives

    KAUST Repository

    Zhao, Yunfeng; Zhang, Daliang; Zhao, Lan; Wang, Guangchao; Zhu, Yihan; Cairns, Amy; Sun, Junliang; Zou, Xiaodong; Han, Yu

    2011-01-01

    materials (e.g., carbon and platinum) via a "hard- templating" synthesis route. The obtained carbon material possesses large surface area (∼1900 m2/g), high pore volume (1.56 cm 3/g), and remarkable gas adsorption capability at both cryogenic temperatures

  8. Synthesis of a metabolically stable modified long-chain fatty acid salt and its photolabile derivative

    Energy Technology Data Exchange (ETDEWEB)

    Stoll, G.H.; Voges, R.; Gerok, W.; Kurz, G. (Institut fuer Organische Chemie and Biochemie, Universitaet Freiburg (Germany))

    1991-05-01

    An analogue of the long-chain fatty acid salt, sodium stearate, was synthesized in which the hydrogen atoms at carbons 2, 3, and 18 were replaced by fluorine. The key step in the synthesis was the addition of 3-iodo-2,2,3,3-tetrafluoropropanoic acid amide to 15,15,15-trifluoro-1-pentadecene. Radioactivity was introduced by catalytic reduction of 2,2,3,3,18,18,18-heptafluoro-4-octadecenoic acid amide with carrier-free tritium gas yielding a product with the specific radioactivity of 2.63 TBq/mmol. The resulting 2,2,3,3,18,18,18-heptafluoro-4-octadecenoic acid has a pKa of about 0.5 and is completely dissociated under normal physiological conditions. The fluorinated fatty acid salt analogue is readily taken up into hepatocytes and proved to be metabolically inert. In an approach to the identification of proteins involved in long-chain fatty acid salt transport across membranes and intracellular compartments, the photolabile derivative 11,11-azo-2,2,3,3,18,18,18-heptafluoro(G-3H)octadecanoic acid sodium salt was synthesized with a specific radioactivity of 2.63 TBq/mmol. Photolysis of the photolabile derivative, using a light source with a maximum emission at 350 nm, occurred with a half-life of 1.5 min. The generated carbene reacted with 14C-labeled methanol and acetonitrile with covalent bond formation of 6-13%. Its efficacy for photoaffinity labeling was demonstrated by incorporation into serum albumin, the extracellular fatty acid salt-binding protein, as well as into the intracellular fatty acid salt-binding protein (FABP) of rat liver with the molecular weight of 14,000.

  9. Catalytic destruction of tar in biomass derived producer gas

    International Nuclear Information System (INIS)

    Zhang Ruiqin; Brown, Robert C.; Suby, Andrew; Cummer, Keith

    2004-01-01

    The purpose of this study is to investigate catalytic destruction of tar formed during gasification of biomass, with the goal of improving the quality of the producer gas. This work focuses on nickel based catalysts treated with alkali in an effort to promote steam gasification of the coke that deposits on catalyst surfaces. A tar conversion system consisting of a guard bed and catalytic reactor was designed to treat the producer gas from an air blown, fluidized bed biomass gasifier. The guard bed used dolomite to crack the heavy tars. The catalytic reactor was used to evaluate three commercial steam reforming catalysts. These were the ICI46-1 catalyst from Imperial Chemical Industry and Z409 and RZ409 catalysts from Qilu Petrochemical Corp. in China. A 0.5-3 l/min slipstream from a 5 tpd biomass gasifier was used to test the tar conversion system. Gas and tar were sampled before and after the tar conversion system to evaluate the effectiveness of the system. Changes in gas composition as functions of catalytic bed temperature, space velocity and steam/TOC (total organic carbon) ratio are presented. Structural changes in the catalysts during the tests are also described

  10. Synthesis of acrylates and methacrylates from coal-derived syngas

    Energy Technology Data Exchange (ETDEWEB)

    Spivey, J.J.; Gogate, M.R.; Jang, B.W.L. [Bechtel, San Francisco, CA (United States)] [and others

    1995-12-31

    Acrylates and methacrylates are among the most widely used chemical intermediates in the world. One of the key chemicals of this type is methyl methacrylate. Of the 4 billion pounds produced each year, roughly 85% is made using the acetone-cyanohydrin process, which requires handling of large quantities of hydrogen cyanide and produces ammonium sulfate wastes that pose an environmental disposal challenge. The U.S. Department of Energy and Eastman Chemical Company are sharing the cost of research to develop an alternative process for the synthesis of methyl methacrylate from syngas. Research Triangle Institute is focusing on the synthesis and testing of active catalysts for the condensation reactions, and Bechtel is analyzing the costs to determine the competitiveness of several process alternatives. Results thus far show that the catalysts for the condensation of formaldehyde and the propionate are key to selectively producing the desired product, methacrylic acid, with a high yield. These condensation catalysts have both acid and base functions and the strength and distribution of these acid-base sites controls the product selectivity and yield.

  11. A facile synthesis of phenazine and quinoxaline derivatives using magnesium sulfate heptahydrate as a catalyst

    Directory of Open Access Journals (Sweden)

    BAHADOR KARAMI

    2011-09-01

    Full Text Available Convenient and simple procedures for the synthesis of phenazine and quinoxaline derivatives were developed via a reaction of o-phenylenediamines and 1,2-dicarbonyl compounds. In addition, the synthesis of two new 1,4-benzodiazine derivatives and the catalytic activity of magnesium sulfate heptahydrate (MgSO4·7H2O in the room temperature condensation of o-phenylenediamines and 1,2-dicarbonyl compounds in ethanol as solvent are reported. This method has many appealing attributes, such as excellent yields, short reaction times, and simple work-up procedures.

  12. A green protocol for the synthesis of quinoxaline derivatives catalyzed by polymer supported sulphanilic acid

    Directory of Open Access Journals (Sweden)

    Umesh P. Tarpada

    2017-05-01

    Full Text Available Polymer supported sulphanilic acid was found to be an effective heterogeneous catalyst for one pot synthesis of various quinoxaline derivatives from the condensation reaction between 1,2-diamines and 1,2-dicarbonyl compounds in ethanol. Synthesis was attempted under reflux as well as at room temperature using ethanol as the solvent to afford excellent yields. Heterogeneity of the catalyst allowed its recycling for five times with almost retention in catalytic activity. Prepared quinoxaline derivatives were also tested for their antioxidant activity by the FRAP assay method.

  13. Synthesis and Spectral Study of Novel Norfloxacin Derivatives

    Directory of Open Access Journals (Sweden)

    Pradeep Yadav

    2008-01-01

    Full Text Available Reaction of [1-ethyl-6-fluoro-1,4-dihydro-4-oxo-7-(1-piperazinyl-quinolone-3-carboxylic acid (norfloxacin with thiazole / benzothiazole diazonium chloride to get new piperazine substituted norfloxacin derivative. These norfloxacin derivatives were further condensed with various β-diketone to get novel acid derivatives of 1-Ethyl-6-fluoro-4-oxo-7- [4 (thiazol-2-yldiazenyl-piperzin-1-yl]-1,4-dihydro-quinoline-3-carboxylic acid (6a-e and 7-(4-(benzo[d]thiazol-2-yldiazenylpiperazin-1-yl-1-ethyl-6-fluoro-4-oxo-1, 4-dihydroquinoline-3-carboxylic acid (6 f-j. Structures of these compounds were established on the basis of spectral studies viz. IR, 1H NMR etc.

  14. Design, Synthesis and Insecticidal Activity of Novel Phenylurea Derivatives

    Directory of Open Access Journals (Sweden)

    Jialong Sun

    2015-03-01

    Full Text Available A series of novel phenylurea derivatives were designed and synthesized according to the method of active groups linkage and the principle of aromatic groups bioisosterism in this study. The structures of the novel phenylurea derivatives were confirmed based on ESI-MS, IR and 1H-NMR spectral data. All of the compounds were evaluated for the insecticidal activity against the third instars larvae of Spodoptera exigua Hiibner, Plutella xyllostella Linnaeus, Helicoverpa armigera Hubner and Pieris rapae Linne respectively, at the concentration of 10 mg/L. The results showed that all of the derivatives displayed strong insecticidal activity. Most of the compounds presented higher insecticidal activity against S. exigua than the reference compounds tebufenozide, chlorbenzuron and metaflumizone. Among the synthesized compounds, 3b, 3d, 3f, 4b and 4g displayed broad spectrum insecticidal activity.

  15. Pressurised combustion of biomass-derived, low calorific value, fuel gas

    Energy Technology Data Exchange (ETDEWEB)

    Andries, J.; Hoppesteyn, P.D.J.; Hein, K.R.G. [Lab. for Thermal Power Engineering, Dept. of Mechanical Engineering and Marine Technology, Delft Univ. of Technology (Netherlands)

    1996-12-31

    The Laboratory for Thermal Power Engineering of the Delft University of Technology is participating in an EU-funded, international R + D project which is designed to aid European industry in addressing issues regarding pressurised combustion of biomass-derived, low calorific flue fuel gas. The objects of the project are: To design, manufacture and test a pressurised, high temperature gas turbine combustor for biomass derived LCV fuel gas; to develop a steady-state and dynamic model describing a combustor using biomass-derived, low calorific value fuel gases; to gather reliable experimental data on the steady-state and dynamic characteristics of the combustor; to study the steady-state and dynamic plant behaviour using a plant layout wich incorporates a model of a gas turbine suitable for operation on low calorific value fuel gas. (orig)

  16. Pressurised combustion of biomass-derived, low calorific value, fuel gas

    Energy Technology Data Exchange (ETDEWEB)

    Andries, J; Hoppesteyn, P D.J.; Hein, K R.G. [Lab. for Thermal Power Engineering, Dept. of Mechanical Engineering and Marine Technology, Delft Univ. of Technology (Netherlands)

    1997-12-31

    The Laboratory for Thermal Power Engineering of the Delft University of Technology is participating in an EU-funded, international R + D project which is designed to aid European industry in addressing issues regarding pressurised combustion of biomass-derived, low calorific flue fuel gas. The objects of the project are: To design, manufacture and test a pressurised, high temperature gas turbine combustor for biomass derived LCV fuel gas; to develop a steady-state and dynamic model describing a combustor using biomass-derived, low calorific value fuel gases; to gather reliable experimental data on the steady-state and dynamic characteristics of the combustor; to study the steady-state and dynamic plant behaviour using a plant layout wich incorporates a model of a gas turbine suitable for operation on low calorific value fuel gas. (orig)

  17. Potential of synthesis gas production from rubber wood chip gasification in a bubbling fluidised bed gasifier

    International Nuclear Information System (INIS)

    Kaewluan, Sommas; Pipatmanomai, Suneerat

    2011-01-01

    Experiments of rubber wood chip gasification were carried out in a 100-kW th bubbling fluidised bed gasifier to investigate the effect of air to fuel ratio (represented as equivalence ratio - ER) on the yield and properties of synthesis gas. For all experiments, the flow rate of ambient air was fixed, while the feed rate of rubber wood chip was adjusted to vary ER in the range of 0.32-0.43. Increasing ER continuously raised the bed temperature, which resulted in higher synthesis gas yield and lower yield of ash and tar. However, higher ER generally gave synthesis gas of lower heating value, partly due to the dilution of N 2 . Considering the energy efficiency of the process, the optimum operation was achieved at ER = 0.38, which yielded 2.33 Nm 3 of synthesis gas per kg of dry biomass at the heating value of 4.94 MJ/Nm 3 . The calculated carbon conversion efficiency and gasification efficiency were 97.3% and 80.2%, respectively. The mass and energy balance of the gasification process showed that the mass and energy distribution was significantly affected by ER and that the energy losses accounted for ∼25% of the total output energy. The economical assessment of synthesis gas utilisation for heat and electricity production based on a 1-MW th bubbling fluidised bed gasifier and the operational data resulting from the rubber wood chip gasification experiments in this study clearly demonstrated the attractiveness of replacing heavy fuel oil and natural gas by the synthesis gas for heat applications in terms of 70% and 50% annual saving of fuel cost, respectively. However, the case of electricity production does not seem a preferable option due to its current technical and non-technical barriers.

  18. Synthesis, characterization and photophysical properties of ESIPT reactive triazine derivatives

    International Nuclear Information System (INIS)

    Kuplich, Marcelo D.; Grasel, Fabio S.; Campo, Leandra F.; Rodembusch, Fabiano S.; Stefani, Valter

    2012-01-01

    Four new reactive fluorescent triazine derivatives were obtained from nucleophilic aromatic substitution of cyanuric chloride. The compounds were characterized by infrared spectroscopy (IR), nuclear magnetic resonance ( 13 C and 1 H NMR) and high resolution mass spectrometry (HRMS MALDI). UV-Vis and steady-state fluorescence (in solution and in solid state) spectroscopies were also applied to characterize the photophysical behavior. The dyes are fluorescent by an intramolecular proton transfer mechanism (ESIPT) in the blue-orange region, with a large Stokes shift between 6365-10290 cm-1. The fluorescent cyanuric derivatives could successfully react with cellulose fibers to give new fluorescent cellulosic materials. (author)

  19. Synthesis and anticandidal activity of some imidazopyridine derivatives.

    Science.gov (United States)

    Kaplancikli, Zafer Asim; Turan-Zitouni, Gülhan; Ozdemir, Ahmet; Revial, Gilbert

    2008-12-01

    New hydrazide derivatives of imidazo[1,2-a]pyridine have been synthesized and evaluated for anticandidal activity. The reaction of imidazo[1,2-a]pyridine-2-carboxylic acid hydrazides with various benzaldehydes gave N-(benzylidene)imidazo[ 1,2-a]pyridine-2-carboxylic acid hydrazide derivatives. Their anticandidal activities against Candida albicans and Candida glabrata (isolates obtained from Osmangazi University, Faculty of Medicine, Eskisehir, Turkey), Candida albicans (ATCC 90028), Candida utilis (NRLL Y-900), Candida tropicalis (NRLL Y-12968), Candida krusei (NRLL Y-7179), Candida zeylanoides (NRLL Y-1774), and Candida parapsilosis (NRLL Y-12696) were investigated.

  20. Synthesis and biological evaluation of 2-substituted benzimidazole derivatives

    Directory of Open Access Journals (Sweden)

    Gurusamy Mariappan

    2015-09-01

    Full Text Available A novel series of 2-substituted benzimidazole derivatives (3a–3j were synthesized by the reaction of 2-chloro methyl benzimidazole with substituted primary aromatic amines. All the compounds were characterized by UV, IR, 1H NMR, mass spectral data and CHN elemental analysis. The synthesized derivatives were screened for analgesic and anti-inflammatory activities. All the compounds showed significant effect at 100 mg/kg p.o. and the experimental data are statistically significant at p < 0.01 level.

  1. Synthesis and antimalarial evaluation of novel isocryptolepine derivatives.

    Science.gov (United States)

    Whittell, Louise R; Batty, Kevin T; Wong, Rina P M; Bolitho, Erin M; Fox, Simon A; Davis, Timothy M E; Murray, Paul E

    2011-12-15

    A series of mono- and di-substituted analogues of isocryptolepine have been synthesized and evaluated for in vitro antimalarial activity against chloroquine sensitive (3D7) and resistant (W2mef) Plasmodium falciparum and for cytotoxicity (3T3 cells). Di-halogenated compounds were the most potent derivatives and 8-bromo-2-chloroisocryptolepine displayed the highest selectivity index (106; the ratio of cytotoxicity (IC(50)=9005 nM) to antimalarial activity (IC(50)=85 nM)). Our evaluation of novel isocryptolepine compounds has demonstrated that di-halogenated derivatives are promising antimalarial lead compounds. Copyright © 2011 Elsevier Ltd. All rights reserved.

  2. Fuel from the synthesis gas - the role of process engineering

    Energy Technology Data Exchange (ETDEWEB)

    Stelmachowski, Marek; Nowicki, Lech [Technical Univ. of Lodz, Dept. of Environmental Engineering Systems, Lodz (Poland)

    2003-02-01

    The paper presents the conclusions obtained in the investigations of methanol synthesis, Fischer-Tropsch synthesis, and higher alcohols synthesis from syngas as a raw material in slurry reactors. The overview of the role of process engineering was made on the basis of the experience in optimizing process conditions, modeling reactors and working out new technologies. Experimental data, obtained with a laboratory-stirred autoclave and theoretical considerations were used to develop the kinetic models that can describe the product formation and the model of the simultaneous phase and chemical equilibrium for the methanol and Fischer-Tropsch syntheses in the slurry reactors. These models were employed in modeling of the bubble-column slurry reactor (BCSR). Based on these considerations, a computer simulation of the low-pressure methanol synthesis for the pilot-scale, BCSR, was devised. The results of the calculations and the conclusions could be employed in the process for designing an industrial plant. (Author)

  3. Literature Review and Synthesis for the Natural Gas Infrastructure

    Energy Technology Data Exchange (ETDEWEB)

    Folga, Stephen [Argonne National Lab. (ANL), Argonne, IL (United States); Talaber, Leah [Argonne National Lab. (ANL), Argonne, IL (United States); McLamore, Michael [Argonne National Lab. (ANL), Argonne, IL (United States); Kraucunas, Ian [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); McPherson, Timothy [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Parrott, Lori [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Manzanares, Trevor [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-06-01

    The efficient and effective movement of natural gas from producing regions to consuming regions requires an extensive and elaborate transportation system. In many instances, natural gas produced from a particular well has to travel a great distance to reach its point of use. The transportation system for natural gas consists of a complex network of pipelines designed to quickly and efficiently transport the gas from its origin to areas of high demand. The transportation of natural gas is closely linked to its storage: If the natural gas being transported is not immediately required, it can be put into storage facilities until it is needed. A description of the natural gas transmission, storage, and distribution (TS&D) sector is provided as follows.

  4. Synthesis, Optical Properties and Applications for New Trianguleniums Derivatives

    DEFF Research Database (Denmark)

    Santella, Marco

    The development of new types of emissive organic dyes is an exciting area of research due to the applicability of these compounds in a wide range of disciplines. Cationic triangulenium salts are highly stable carbenium ions with a planar conformation. The convenient and versatile synthetic proced...... focused on the synthesis of thioether para substituted dyes, where the reactivity of various para-methoxy substituted propeller shaped cations towards different alkyl thiols was examined. Furthermore, ringclosure reactions of these thioether bearing propellers in order to obtain trioxa...... structures. These dyes possess excellent emissive properties with possible applications as cell staining agents or as fluorescent probes. Lastly, I focused on the use of triangulenes as binding group for molecular electronics. It has been shown that TATA can form self-assembled monolayers (SAMs) on a gold...

  5. Synthesis of a phosphorothioate derivative of flavin mononucleotide

    International Nuclear Information System (INIS)

    Calhoun, J.P.; Miziorko, H.M.; Otvos, J.D.; Masters, B.S.S.

    1987-01-01

    The synthesis of riboflavin-5'-phosphorothioate (5'-FMNS), an analog of riboflavin-5'-phosphate (FMN), is described. 5'-FMNS is produced from the alkaline hydrolysis of riboflavin-4',5'-cyclic phosphorothioate (cFMNS). The cyclic phosphorothioate is produced upon reaction of riboflavin with thiophosphoryl chloride in trimethyl phosphate. The phosphorothioate compounds have been characterized by 13 C and 31 P NMR and the purified 5'-FMNS is isolated by preparative HPLC. Preliminary results indicate that this analog of FMN is capable of replacing FMN in at least on flavoprotein, NADPH-cytochrome P-450 reductase, and is competent in reconstituting the cytochrome c reductase activity of this enzyme. Full characterization of this derivatized flavoprotein is in progress

  6. Synthesis and radiation resistance of fullerenes and fullerene derivatives

    Energy Technology Data Exchange (ETDEWEB)

    Shilin, V. A., E-mail: shilin@pnpi.spb.ru; Lebedev, V. T.; Sedov, V. P.; Szhogina, A. A. [St. Petersburg Nuclear Physics Institute, National Research Centre “Kurchatov Institute” (Russian Federation)

    2016-07-15

    The parameters of an electric-arc facility for the synthesis of fullerenes and endohedral metallofullerenes are optimized. The resistance of C{sub 60} and C{sub 70} fullerenes and C{sub 60}(OH){sub 30} and C{sub 70}(OH){sub 30} fullerenols against neutron irradiation is studied. It is established that the radiation resistance of the fullerenes is higher than that of the fullerenols, but the radiation resistance of the Gd@C{sub 2n} endometallofullerenes is lower than that of the corresponding Gd@C{sub 2n}(OH){sub 38} fullerenols. The radiation resistance of mixtures of Me@C{sub 2n}(OH){sub 38} (Me = Gd, Tb, Sc, Fe, and Pr) endometallofullerenes with C{sub 60}(OH){sub 30} is determined. The factors affecting the radiation resistance of the fullerenes and fullerenols are discussed.

  7. Novel synthesis of a strained para-cyclophane derivative

    Institute of Scientific and Technical Information of China (English)

    Zhi Hao Shi; Yun Yang Wei

    2007-01-01

    A [P. Rajakumar, A.M.A. Rasheed, Tetrahedron 61(22) (2005) 5351] para-cyclophane derivative was synthesized via intramolecular esterification of a dipeptide surrogate containing asparagine to form tetrahydropyrimidinone ring. The structures of the product and intermediates were characterized by 1H NMR, 13C NMR and mass spectrum.

  8. Clean and Efficient Synthesis of Isoxazole Derivatives in Aqueous Media

    Directory of Open Access Journals (Sweden)

    Daqing Shi

    2013-11-01

    Full Text Available A series of 5-arylisoxazole derivatives were synthesized via the reaction of 3-(dimethyl-amino-1-arylprop-2-en-1-ones with hydroxylamine hydrochloride in aqueous media without using any catalyst. This method has the advantages of easier work-up, mild reaction conditions, high yields, and an environmentally benign procedure.

  9. Synthesis and biological evaluation of vinylogous combretastatin A-4 derivatives.

    Science.gov (United States)

    Kaffy, Julia; Pontikis, Renée; Florent, Jean-Claude; Monneret, Claude

    2005-07-21

    Stereospecific syntheses of the Z-E and E-Z vinylogues of combretastatin A-4, and two B-ring related analogues, were achieved through a Suzuki-Miyaura coupling. As compared to CA4, the derivative with a phenyl moiety has shown increased potency in its ability to inhibit tubulin polymerisation.

  10. Synthesis of Novel Ferrocenyl-containing Thiazole Derivatives

    Institute of Scientific and Technical Information of China (English)

    Ling SHAO; Yan HU; Xin ZHOU; Zhong JIN; Jian Bing LIU; Jian Xin FANG

    2006-01-01

    Novel ferrocenyl-containing thiazole derivatives have been synthesized from 2-amino-4-ferrocenyl-5-(1H-1, 2, 4-triazole-1-yl)thiazole and acyl chloride. And their structures were determined by 1H NMR and elemental analysis.

  11. Synthesis and Biological Activity Evaluation of Novel Heterocyclic Pleuromutilin Derivatives

    Directory of Open Access Journals (Sweden)

    Yunpeng Yi

    2017-06-01

    Full Text Available A series of pleuromutilin derivatives were synthesized by two synthetic procedures under mild reaction conditions and characterized by Nuclear Magnetic Resonance (NMR, Infrared Spectroscopy (IR, and High Resolution Mass Spectrometer (HRMS. Most of the derivatives with heterocyclic groups at the C-14 side of pleuromutilin exhibited excellent in vitro antibacterial activities against Staphylococcus aureus, methicillin-resistant Staphylococcus aureus (MRSA, methicillin-resistant Staphylococcus epidermidis (MRSE, and vancomycin-resistant Enterococcus (VRE in vitro antibacterial activity. The synthesized derivatives which contained pyrimidine rings, 3a, 3b, and 3f, displayed modest antibacterial activities. Compound 3a, the most active antibacterial agent, displayed rapid bactericidal activity and affected bacterial growth in the same manner as that of tiamulin fumarate. Moreover, molecular docking studies of 3a and lefamulin provided similar information about the interactions between the compounds and 50S ribosomal subunit. The results of the study show that pyrimidine rings should be considered in the drug design of pleuromutilin derivatives.

  12. Purine derivative excretion and microbial protein synthesis in sheep ...

    African Journals Online (AJOL)

    In a 3 x 3 Latin square design experiment, urinary excretions of purine derivatives (allantoin N, Uric acid N, Xanthine + Hypoxanthine N) were measured and used to estimate microbial N yield in 9 sheep fed roughage- based diet supplemented with 0, 150 and 300g DM grass silage respectively. Daily urinary excretions of ...

  13. Synthesis of the new derivatives of alkaloid glaucine

    International Nuclear Information System (INIS)

    Mukusheva, G.K.; Zhumagalieva, Zh.Zh.; Turmukhambetov, A.Zh.; Kazantsev, A.V.

    2005-01-01

    On the basis of aporphine alkaloid glaucine by reactions of halogenation, amino-methylation, acetylation and with esters of boronic acid new derivatives of glaucine were synthesized. The structures of obtained compounds were determined on basis of IR, 13 C, 1 H, 11 B NMR spectral data

  14. Synthesis and anticancer evaluation of (-1)- aretigenin derivatives

    International Nuclear Information System (INIS)

    Xu, Y.; Chen, G.

    2014-01-01

    Seven (-)-arctigenin derivatives 1-7 were designed and synthesized by using Mannich and acylation methods to improve the activity and bioavailability of (-)-arctigenin. Structures of compounds 1-7 were elucidated on the basis of spectroscopic analysis and chemical evidence. Anticancer activity of these compounds on SGC7901 was assayed in vitro. (author)

  15. Synthesis and anticancer evaluation of (-1)- aretigenin derivatives

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Y.; Chen, G. [Liaoning Univ. of Traditional Chinese Medicine, Dalian (China)

    2014-10-15

    Seven (-)-arctigenin derivatives 1-7 were designed and synthesized by using Mannich and acylation methods to improve the activity and bioavailability of (-)-arctigenin. Structures of compounds 1-7 were elucidated on the basis of spectroscopic analysis and chemical evidence. Anticancer activity of these compounds on SGC7901 was assayed in vitro. (author)

  16. Synthesis of Phthalimide Derivatives as Potential PPAR-γ Ligands

    Directory of Open Access Journals (Sweden)

    So Hyeon Eom

    2016-06-01

    Full Text Available Paecilocin A, a phthalide derivative isolated from the jellyfish-derived fungus Paecilomyces variotii, activates PPAR-γ (Peroxisome proliferator-activated receptor gamma in rat liver Ac2F cells. Based on a SAR (Structure-activity relationships study and in silico analysis of paecilocin A-mimetic derivatives, additional N-substituted phthalimide derivatives were synthesized and evaluated for PPAR-γ agonistic activity in both murine liver Ac2F cells and in human liver HepG2 cells by luciferase assay, and for adipogenic activity in 3T3-L1 cells. Docking simulation indicated PD6 was likely to bind most strongly to the ligand binding domain of PPAR-γ by establishing crucial H-bonds with key amino acid residues. However, in in vitro assays, PD1 and PD2 consistently displayed significant PPAR-γ activation in Ac2F and HepG2 cells, and adipogenic activity in 3T3-L1 preadipocytes.

  17. Synthesis of water soluble photo-initiators of thioxanthone derivatives

    International Nuclear Information System (INIS)

    Qi Guozhen; Wang Jindi; Lin Yiqing

    1999-01-01

    Eight new photo-initiators of water-soluble thioxanthone derivatives were prepared. These compounds were identified by IR, NMR, MS and elemental analysis etc. The UV absorption wavelength, molar absorption coefficient and fluorescent quantum yield were determined. Furthermore, the relationship between structure and properties was discussed

  18. Synthesis of water soluble photo-initiators of thioxanthone derivatives

    Energy Technology Data Exchange (ETDEWEB)

    Guozhen, Qi; Jindi, Wang; Yiqing, Lin [Inst. of Fine Chemicals ECUST, Shanghai (China)

    1999-07-01

    Eight new photo-initiators of water-soluble thioxanthone derivatives were prepared. These compounds were identified by IR, NMR, MS and elemental analysis etc. The UV absorption wavelength, molar absorption coefficient and fluorescent quantum yield were determined. Furthermore, the relationship between structure and properties was discussed.

  19. Synthesis of azido derivatives of mucobromic acid | D. Jumbam ...

    African Journals Online (AJOL)

    Mucobromic acid is a highly reactive multicentered molecule. It was converted to its corresponding but unstable diazido derivative by reaction with two equivalents of sodium azide. The resultant 3,4-diazido-5-hydroxyfuran-2(5H)-one was obtained in moderate yield (42%) but decomposed readily even at low temperatures.

  20. Homolytic iodination and nitration of some benzene derivatives in the gas phase

    International Nuclear Information System (INIS)

    Vonk, W.F.M.

    1980-01-01

    Two gas phase reactions, involving the iodination and nitration of benzene derivatives, are described. The experimental techniques of the apparatus and the methods used are outlined. The kinetic H/D isotope effect in the gas phase nitration of benzene with NO 2 is determined. (C.F.)

  1. Synthesis and complex forming property of phosphor acid derivatives

    International Nuclear Information System (INIS)

    Babaev, B.N.

    2004-01-01

    Full text:With the aim to get new effective and selective extra gents of noble and non-ferrous metals from acid solution and industrial sewage, research of the dependence of 'structure effectiveness' the various phosphor acid derivatives with logical changeable structure (thio phosphor acids, derivatives of dialkoxythiophosphor, O-alkyl-methylphosphon, alkylphenylphosphon, diphenylphosphine acids also 4 methyl-1,3,2 dioxaphosphorinane) which contain different functional groups, the remains of heterocyclic amines and alkaloids, new derivatives of some analytical reagents were synthesized. The structure of synthesized compounds is approved by the results of IR-, PMR-, mass-spectrum analyze. Researching mass-spectrum decay of synthesized phosphor acid derivatives we defined that differing from O-dihexyl-S-propargyl-benzylthio phosphat, mass spectrum decay of O-dialkyl-S-(piperdynobutin-2-il)thio phosphat is characterized by the appearing [M-H] + ions and during the decay ions with high intensiveness are formed. Fragmentation of M + O-alkyl-O-(aminoalkyl)phenylphosphonate proceeds in various directions and characterized with the great number of phosphor containing ions, the possession of the second phenyl radical in the molecule of diphenylphosphon acid derivatives changes the fragmentation of molecular ion of diphenylphosphon acid derivatives. The process of extraction of noble (Au, Ag, Pt, Pd, Os) metals from hydrochloric-sulphur-nitrogen acid medium was analyzed by radioactive indicator's method. It was noticed that structure, strength, conformation of compounds, the temperature, of acid medium (0,1-10 M) and the nature of acids (HCL, H 2 SO 4 , HNO 3 ) could have strong influence to the effectiveness of metal extraction. During the research of metals extraction from pure solutions we can see the followings: 1) There are such substances, which can be used as effective group reagent towards the Au, Ag and Pd. 2) Derivatives with acetylene extract ions of gold from

  2. Refuse derived fuel incineration: Fuel gas monitoring and analysis

    International Nuclear Information System (INIS)

    Ranaldi, E.; Coronidi, M.; De Stefanis, P.; Di Palo, C.; Zagaroli, M.

    1993-11-01

    Experience and results on refuse derived fuel (selected from municipal solid wastes) incineration are reported. The study involved the investigation of inorganic compounds (heavy metals, acids and toxic gases) emissions, and included feeding materials and incineration residues characterization and mass balance

  3. Green synthesis of chalcones derivatives as intermediate of flavones and their antibacterial activities

    Energy Technology Data Exchange (ETDEWEB)

    VH, Elfi Susanti, E-mail: elsantivh@yahoo.com; Redjeki, Tri, E-mail: tri-redjeki@yahoo.com [Universitas Sebelas Maret, Ir Sutami 36A Surakarta Indonesia, 57126 (Indonesia); Matsjeh, Sabirin, E-mail: sabirin-mara@yahoo.com; Wahyuningsih, Tutik Dwi, E-mail: mustofajogya@yahoo.co.id [Department of Chemistry FMJPA Universitas Gadjah Mada, Jl Sekip Utara, Yogyakarta Indonesia 55281 (Indonesia); Mustofa, E-mail: tutikdw@hotmail.com [Faculty of Medicine, Universitas Gadjah Mada, Yogyakarta Jl. Sekip Utara Yogyakarta Indonesia, 55281 (Indonesia)

    2016-02-08

    Four chalcones derivatives have been synthesized from 3,4-dimethoxybenzaldehyde and acetophenone derivatives (2-hydroxy acetophenone, 2,4-dihydroxy acetophenone, 2,5-dihydroxy acetophenone and 2,6-dihydroxy acetophenone). The synthesis of these chalcones were conducted by Claisen-Schmidt condensation using grinding techniques at room temperature in the absence of solvents. The chalcones were prepared by grinding together equivalent amount of the approriate hydroxyacetophenone and 3,4-dimethoxybenzaldehyde in the presence of solid sodium hydroxide. Grinding techniques for synthesis of the chalcones derivatives is simple, efficient and environmentally benign compared to conventional methods. Then, the four chalcones derivatives undergo cyclization reactions to produce four flavones after reacted with iodine. The synthesized compounds were characterized by spectrometry (IR, {sup 1}H-NMR, {sup 13}C-NMR and MS)

  4. Synthesis of Nanoparticles in a Pulsed-Periodic Gas Discharge and Their Potential Applications

    Science.gov (United States)

    Ivanov, V. V.; Efimov, A. A.; Myl'nikov, D. A.; Lizunova, A. A.

    2018-03-01

    Conditions for the synthesis of three types nanoparticles (SnO2, Al2O3, and Ag) with typical sizes in the range of 4 to 10 nm and a performance of 0.4 g/h are employed in a pulsed-periodic gas discharge in an atmosphere of air. Spherical Ge nanoparticles with a characteristic size of 13 nm are synthesized by these means for the first time with a performance of around 10 mg/h. The specific energy consumption in the synthesis of nanoparticles is for these materials in the range of 2000 to 5000 kW h/kg. The prospects for using tinoxide nanoparticles in sensor components and jets of silver nanoparticles for aerosol printing are discussed. The merits and demerits of the pulsed gas-discharge method among other gas-phase approaches to the synthesis of nanoparticles are analyzed for the current level of development.

  5. Studies on Synthesis of Some Novel Heterocyclic Azlactone Derivatives and Imidazolinone Derivatives and their Antimicrobial Activity

    Directory of Open Access Journals (Sweden)

    Rakesh N. Mistry

    2005-01-01

    Full Text Available p - Methyl benzoic acid on reaction with phosphorus pentachloride gives p - methyl benzoyl chloride derivative which on condensation with glycine gives p - methyl benzoyl glycine derivative. Now, this p - methyl benzoyl glycine derivative on condensation with various substituted aldehydes gives corresponding substituted 4 - [aryl methylidine] - 2 - [p - methyl phenyl] - oxazole - 5 - one derivatives [1(a-j]. Further, these derivatives [1(a-j] on condensation with 4 , 4’ - diamino diphenyl sulphone gives corresponding substituted imidazolinone - dibenzsulphone derivatives [2(a-j], on condensation with 4 , 4’ - diamino diphenyl methane gives corresponding substituted imidazolinone - dibenzmethane derivatives [3(a-j], on condensation with 4,4’- diamino benzanilide gives corresponding substituted imidazolinone - benzanilide derivatives [4(a-j] and on condensation with 2 - amino pyridine gives corresponding substituted imidazolinone - pyridine derivatives [5(a-j] respectively. Structure elucidation of synthesised compounds has been made on the basis of elemental analysis, I.R. spectral studies and 1H N.M.R. spectral studies. The antimicrobial activity of the synthesised compounds has been studied against the cultures “Staphylococcus aureus”, “Escherichia coli” and “Candela albicans”.

  6. Synthesis, chemical and biological properties of the new mono- and bis-derivatives of imidazoles

    Directory of Open Access Journals (Sweden)

    E. V. Welchinska

    2014-12-01

    Full Text Available The aim of research. The problem of finding effective antitumour medical preparation with low toxicity is an important issue of medical and pharmaceutical chemistry. Knowledge of cancer cell features and its metabolism enables to predict the direction of chemical and biological research, to conduct a targeted synthesis of potential drugs, and to assess their applicability in oncological practice as antitumor agents. The purpose of work is to explain preformed heterocycles as purines, its synthesis and investigation of chemical and biological properties. After construction of the potential active structures we proposed the new method of original derivatives synthesis which are received on the base of imidazole, from one side, and fluorocontaining common anesthetic halothane (2-bromo-1,1,1-trifluoro-2-chloroethane from other side. Molecular complex of more perspective biologically active bis-imidazole with antitumour bacterial lectine has been received. With the purpose to synthesize potential antitumour compounds on the base of halothane and imidazole, new convenient methods for the preparation of original heterocyclic derivatives of imidazole have been described. The structure and composition of synthesized compound has been confirmed by the methods of elemental analysis, IR- and NMRІН-spectra. Materials and methods. The majority of the absolute organic solvents (benzene, dimethylformamide, ethyl ester employed in the present studies were distilled before their use. Organic solvents were dried over anhydrous magnesium sulfate or metallic sodium. Gas-liquid chromatography was carried out by Perkin Elmer chromatograph with UV-detector ("Perkin", Germany. IR spectra were recorded in a UR-20 spectrometer ("Charles Ceise Hena", Germany. The 1HNMR spectra were recorded in DMSO-d6 on a 200 MHz BrakerWP-200 ("Braker", Switzerland or Varian T-60 spectrometer ("Varian", USA. Investigation of critical toxicity of new compounds was carried out at

  7. Synthesis, Characterization and Antimicrobial Activity of New Thiadiazole Derivatives

    Energy Technology Data Exchange (ETDEWEB)

    Mullick, Pooja; Khan, Suroor A.; Verma, Surajpal; Alam, Ozair [Hamdard University, New Delhi (India)

    2010-08-15

    A series of thiadiazole derivatives were synthesized with differently substituted benzoic acids which were cyclized to give differently substituted thiazolidin-4-one. Elemental analysis, IR, {sup 1}H NMR, {sup 13}C NMR and mass spectral data confirmed the structure of the newly synthesized compounds. The derivatives of these moieties were evaluated for antimicrobial activity. Most of the synthesized compounds showed good antimicrobial activity at 200 and 100 μg/mL. Compounds showed most significant antibacterial activity against gram negative test organism Escherichia coli and most significant antifungal activity against test organisms Aspergillus niger and Candida albicans. It was observed that compounds with OCH{sub 3} at 3, 4 position of phenyl ring [5(a-l)] were more potent against microbes as compared to compounds having unsubstituted phenyl ring [4(a-l)].

  8. Design, Synthesis and Antiviral Activity Studies of Schizonepetin Derivatives

    Directory of Open Access Journals (Sweden)

    Anwei Ding

    2013-08-01

    Full Text Available A series of schizonepetin derivatives have been designed and synthesized in order to obtain potent antivirus agents. The antiviral activity against HSV-1 and influenza virus H3N2 as well as the cytotoxicity of these derivatives was evaluated by using cytopathic effect (CPE inhibition assay in vitro. Compounds M2, M4, M5 and M34 showed higher inhibitory activity against HSV-1 virus with the TC50 values being in micromole. Compounds M28, M33, and M35 showed higher inhibitory activity against influenza virus H3N2 with their TC50 values being 96.4, 71.0 and 75.4 μM, respectively. Preliminary biological activity evaluation indicated that the anti-H3N2 and anti-HSV-1 activities improved obviously through the introduction of halogen into the structure of schizonepetin.

  9. Alum as a Catalyst for the Synthesis of Bispyrazole Derivatives

    Directory of Open Access Journals (Sweden)

    Mohammad Ali Zolfigol

    2016-01-01

    Full Text Available Compounds with pyrazolemoieties as nitrogen-containing heterocyclic systems have received attention owing to their diverse biological activities. Alum (KAl(SO42∙12H2O is an inexpensive, reusable and nontoxic catalyst used to synthesize 1H-pyrazole derivatives via the reaction of 3-methyl-1-phenyl-1H-pyrazol-5(4H-one and carbonyl compound under solvent-free conditions at 60 °C. The proposed method has been used for the preparation of 1H-pyrazole derivatives to yield green products for cleaning-in-place and to avoid toxic catalysts and hazardous solvents in accordance with the philosophy of sustainable chemistry.

  10. Synthesis of chitosan derivative with diethyldithiocarbamate and its antifungal activity.

    Science.gov (United States)

    Qin, Yukun; Xing, Ronge; Liu, Song; Li, Kecheng; Hu, Linfeng; Yu, Huahua; Chen, Xiaolin; Li, Pengcheng

    2014-04-01

    With an aim to discover novel chitosan derivatives with enhanced antifungal properties compared with chitosan. Diethyl dithiocarbamate chitosan (EtDTCCS) was investigated and its structure was well identified. The antifungal activity of EtDTCCS against Alternaria porri (A. porri), Gloeosporium theae sinensis Miyake (G. theae sinensis), and Stemphylium solani Weber (S. solani) was tested at 0.25, 0.5, and 1.0 mg/mL, respectively. Compared with plain chitosan, EtDTCCS shows better inhibitory effect with 93.2% inhibitory index on G. theae sinensis at 1.0 mg/mL, even stronger than for polyoxin (82.5%). It was inferred derivatives of this kind may find potential applications for the treatment of various crop-threatening diseases. Copyright © 2014 Elsevier B.V. All rights reserved.

  11. Synthesis of some 16,17-secoandrost-5-ene derivatives

    Directory of Open Access Journals (Sweden)

    Gaković Andrea R.

    2010-01-01

    Full Text Available Starting from 3β-acetoxy-17-oxo-16,17-secoandrost-5-ene-16-nitrile (1, 3β-acetoxy-16,17-secoandrost-5-ene-16-nitrile (4 was synthesized by a three-stage procedure. First, the formyl group of compound 1 was reduced, to yield the alcohol 2. Compound 2 was further transformed to the mesyloxy derivative 3, whose reduction with NaBH3CN gave compound 4. Apart from compound 4 as the main reaction product, two additional products were obtained, for which the GC/MS analysis suggested that they are 8(14 and 14 derivatives of compound 4. Compound 4 was transformed into 3β-hydroxy-16,17-sesoandrost-5-ene-16-nitrile (7, the Oppenauer oxidation of which afforded 3-oxo-16,17-secoandrost-4-ene-16-nitrile (8.

  12. Synthesis and evaluation of antimalarial activity of curcumin derivatives

    International Nuclear Information System (INIS)

    Gomes, Patricia Ramos; Miguel, Fabio Balbino; Almeida, Mauro Vieira de; Couri, Mara Rubia Costa; Oliveira, Michael Eder de; Ferreira, Vanessa Viana; Guimaraes, Daniel Silqueira Martins; Lima, Aline Brito de; Barbosa, Camila de Souza; Oliveira, Mariana Amorim de; Almeida, Mauro Vieira de; Viana, Gustavo Henrique Ribeiro; Varotti, Fernando de Pilla

    2014-01-01

    ne of the main challenges in the development of new antimalarial drugs is to achieve a viable lead candidate with good pharmacokinetic properties. Curcumin has a broad range of biological activities, including antimalarial activity. Herein, we report the antimalarial activity of six curcumin derivatives (6-12) and an initial analysis of their pharmacokinetic properties. Five compounds have demonstrated potent activity against the P. falciparum in vitro (IC 50 values ranging from 1.7 to 15.2 μg mL -1 ), with moderate or low cytotoxicity against the HeLa cell line. The substitution of the carbonyl group in 6 by a 2,4-dinitrophenylhydrazone group (to afford 11) increases the Selective Index. These preliminary results indicate curcumin derivatives as potential antimalarial compounds. (author)

  13. Synthesis and characterization of cellulose derivatives obtained from bacterial cellulose

    International Nuclear Information System (INIS)

    Oliveira, Rafael L. de; Barud, Hernane; Ribeiro, Sidney J.L.; Messaddeq, Younes

    2011-01-01

    The chemical modification of cellulose leads to production of derivatives with different properties from those observed for the original cellulose, for example, increased solubility in more traditional solvents. In this work we synthesized four derivatives of cellulose: microcrystalline cellulose, cellulose acetate, methylcellulose and carboxymethylcellulose using bacterial cellulose as a source. These were characterized in terms of chemical and structural changes by examining the degree of substitution (DS), infrared spectroscopy (FTIR) and nuclear magnetic resonance spectroscopy - NMR 13 C. The molecular weight and degree of polymerization were evaluated by viscometry. The characterization of the morphology of materials and thermal properties were performed with the techniques of X-ray diffraction, electron microscopy images, differential scanning calorimetry (DSC) and thermogravimetric analysis. (author)

  14. Synthesis and proapoptotic activity of oleanolic acid derived amides.

    Science.gov (United States)

    Heller, Lucie; Knorrscheidt, Anja; Flemming, Franziska; Wiemann, Jana; Sommerwerk, Sven; Pavel, Ioana Z; Al-Harrasi, Ahmed; Csuk, René

    2016-10-01

    Thirty-one different 3-O-acetyl-OA derived amides have been prepared and screened for their cytotoxic activity. In the SRB assays nearly all the carboxamides displayed good cytotoxicity in the low μM range for several human tumor cell lines. Low EC50 values were obtained especially for the picolinylamides 14-16, for a N-[2-(dimethylamino)-ethyl] derivative 27 and a N-[2-(pyrrolinyl)-ethyl] carboxamide 28. These compounds were submitted to an extensive biological testing and proved compound 15 to act mainly by an arrest of the tumor cells in the S phase of the cell cycle. Cell death occurred by autophagy while compounds 27 and 28 triggered apoptosis. Copyright © 2016 Elsevier Inc. All rights reserved.

  15. Acyl Meldrum's acid derivatives: application in organic synthesis

    Science.gov (United States)

    Janikowska, K.; Rachoń, J.; Makowiec, S.

    2014-07-01

    This review is focused on an important class of Meldrum's acid derivatives commonly known as acyl Meldrum's acids. The preparation methods of these compounds are considered including the recently proposed and rather rarely used ones. The chemical properties of acyl Meldrum's acids are described in detail, including thermal stability and reactions with various nucleophiles. The possible mechanisms of these transformations are analyzed. The bibliography includes 134 references.

  16. Synthesis and Anticancer Activity of Novel Thiazole-5-Carboxamide Derivatives

    Directory of Open Access Journals (Sweden)

    Wen-Xi Cai

    2016-01-01

    Full Text Available A series of novel 2-phenyl-4-trifluoromethyl thiazole-5-carboxamide derivatives have been synthesized and evaluated for their anticancer activity against A-549, Bel7402, and HCT-8 cell lines. Among the tested compounds, highest activity (48% was achieved with the 4-chloro-2-methylphenyl amido substituted thiazole containing the 2-chlorophenyl group on the two position of the heterocyclic ring. Other structurally similar compounds displayed moderate activity. The key intermediates have been fully characterized.

  17. Synthesis and antibacterial studies of some novel isoxazoline derivatives

    Directory of Open Access Journals (Sweden)

    TEJASKUMAR SHAH

    2007-05-01

    Full Text Available A series of 3-[3-(2,4-dichloro-5-fluorophenyl-5-(2-furyl-4,5-dihydro-1H-pyrazol-1-yl]-5-(substituted phenyl/2-thienylisoxazolines (4a-j were prepared. The structures of the isoxazoline derivatives were confirmed on the bases of elemental analysis and spectral data. The compounds were screened for their in vitro antibacterial activity using gram-positive bacteria and gram-negative bacteria.

  18. Synthesis and characterization of new thiourea and urea derivatives ...

    Indian Academy of Sciences (India)

    Hasti Sudhamani et al. N. S/O. O. N. F. O. N. S. O. N ... All the required chemicals were purchased from Sigma. Aldrich and the ... of remaining compounds (8b-g) and urea derivatives. (9a-d). ..... Nicholas J H, John G J, Kendra L B, Paul G C, Harold. B H, Lisa L K ... Nadaradjane A Nicod L Guyon C Xicluna A Robert. J F and ...

  19. Synthesis and stability of strongly acidic benzamide derivatives

    DEFF Research Database (Denmark)

    Diness, Frederik; Bjerrum, Niels J.; Begtrup, Mikael

    2018-01-01

    Reactivity studies of strong organic acids based on the replacement of one or both of the oxygens in benzoic acids with the trifluoromethanesulfonamide group are reported. Novel derivatives of these types of acids were synthesized in good yields. The generated N-triflylbenzamides were further...... functionalized through cross-coupling and nucleophilic aromatic substitution reactions. All compounds were stable in dilute aqueous solutions. Studies of stability under acidic and basic conditions are also reported....

  20. Design and synthesis of an indol derivative as antibacterial agent against Staphylococcus aureus.

    Science.gov (United States)

    Lenin, Hau-Heredia; Lauro, Figueroa-Valverde; Marcela, Rosas-Nexticapa; Socorro, Herrera-Meza; Maria, López-Ramos; Francisco, Díaz-Cedillo; Elodia, García-Cervera; Eduardo, Pool-Gómez; Josefa, Paat-Estrella; Regina, Cauich-Carrillo; Saidy, Euan-Hau

    2017-10-01

    Several indole derivatives with antibacterial activity have been prepared using different protocols; however, some require special reagents and conditions. The aim of this study involved the synthesis of some indole derivatives using estrone and OTBS-estrone as chemical tools. The synthesis of the indole derivatives involves reactions such as follows: (1) synthesis of two indol derivatives ( 4 or 5 ) by reaction of estrone or OTBS-estrone with phenylhydrazine in medium acid; (2) reaction of 4 or 5 with 6-cloro-1-hexyne in medium basic to form two hexynyl-indol ( 7 or 8 ); (3) preparation of indol-propargylic alcohol derivatives ( 10 or 11 ) by reaction of benzaldehyde with 7 or 8 in medium basic; (4) synthesis of indol-aldehydes ( 12 or 13 ) via oxidation of 10 or 11 with DMSO; (5) synthesis of indeno-indol-carbaldehyde ( 15 or 16 ) via alkynylation/cyclization of 12 or 13 with hexyne in presence of copper(II); (6) preparation indeno-indol-carbaldehyde complex ( 19 or 20 ) via alkynylation/cyclization of 12 or 13 with 1-(hex-5-yn-1-yl)-2-phenyl-1 H -imidazole. The antibacterial effect exerted by the indol-steroid derivatives against Streptococcus pneumoniae and Staphylococcus aureus bacteria was evaluated using dilution method and the minimum inhibitory concentration (MIC). The results showed that only the compound 19 inhibit the growth bacterial of S. aureus . In conclusion, these data indicate that antibacterial activity of 19 can be due mainly to functional groups involved in the chemical structure in comparison with the compounds studied.

  1. Using Noble Gas Measurements to Derive Air-Sea Process Information and Predict Physical Gas Saturations

    Science.gov (United States)

    Hamme, Roberta C.; Emerson, Steven R.; Severinghaus, Jeffrey P.; Long, Matthew C.; Yashayaev, Igor

    2017-10-01

    Dissolved gas distributions are important because they influence oceanic habitats and Earth's climate, yet competing controls by biology and physics make gas distributions challenging to predict. Bubble-mediated gas exchange, temperature change, and varying atmospheric pressure all push gases away from equilibrium. Here we use new noble gas measurements from the Labrador Sea to demonstrate a technique to quantify physical processes. Our analysis shows that water-mass formation can be represented by a quasi steady state in which bubble fluxes and cooling push gases away from equilibrium balanced by diffusive gas exchange forcing gases toward equilibrium. We quantify the rates of these physical processes from our measurements, allowing direct comparison to gas exchange parameterizations, and predict the physically driven saturation of other gases. This technique produces predictions that reasonably match N2/Ar observations and demonstrates that physical processes should force SF6 to be ˜6% more supersaturated than CFC-11 and CFC-12, impacting ventilation age calculations.

  2. Synthesis, antioxidative and whitening effects of novel cysteine derivatives

    Energy Technology Data Exchange (ETDEWEB)

    Ha, Ji Hoon; Kim, Kyoung Mi; Jeong, Yoon Ju; Park, Young Min; Lee, Jae Young; Park, Soo Nam [Dept. of Fine Chemistry, Cosmetic R and D Center, Cosmetic Industry Coupled Collaboration Center, Seoul National University of Science and Technology, Seoul (Korea, Republic of); Park, Jino [Daebong LS. Ltd, Incheon (Korea, Republic of)

    2017-01-15

    Recently, development of biocompatibility functional cosmetic agents as antioxidant or whitening agent has increased. In this study, synthetic cysteine derivatives (DBLS-21, -24, and -33) were developed containing syringic acid and cysteine moieties (l-cysteine ethyl ester, N-acetyl cysteine methyl ester, and N-acetyl cysteine ethyl ester), and their antioxidative and whitening activities were evaluated. The cellular protective effect (τ{sub 50}) of DBLS-21 was 51.1 min at 50 μM on {sup 1}O{sub 2} -induced hemolysis of erythrocytes. This activity was slightly higher than that of α-tocopherol (43.6 min) as a lipophilic antioxidant. In the melanogenesis inhibitory effect, DBLS-21, -24, and -33 was 1.6-, 1.8-, and 2.5-fold higher than arbutin, respectively. In particular, DBLS-21 and -33 was 112.8- and 6.1-fold higher than arbutin, respectively (293.4 μM) on tyrosinase inhibition activity (IC{sub 50} ). But DBLS-24 had no tyrosinase inhibitory activity. These results suggest that cysteine derivatives possess potential for use as an antioxidant agent (DBLS-21) and whitening agents (all derivatives) in cosmetics.

  3. Synthesis, antioxidative and whitening effects of novel cysteine derivatives

    International Nuclear Information System (INIS)

    Ha, Ji Hoon; Kim, Kyoung Mi; Jeong, Yoon Ju; Park, Young Min; Lee, Jae Young; Park, Soo Nam; Park, Jino

    2017-01-01

    Recently, development of biocompatibility functional cosmetic agents as antioxidant or whitening agent has increased. In this study, synthetic cysteine derivatives (DBLS-21, -24, and -33) were developed containing syringic acid and cysteine moieties (l-cysteine ethyl ester, N-acetyl cysteine methyl ester, and N-acetyl cysteine ethyl ester), and their antioxidative and whitening activities were evaluated. The cellular protective effect (τ_5_0) of DBLS-21 was 51.1 min at 50 μM on "1O_2 -induced hemolysis of erythrocytes. This activity was slightly higher than that of α-tocopherol (43.6 min) as a lipophilic antioxidant. In the melanogenesis inhibitory effect, DBLS-21, -24, and -33 was 1.6-, 1.8-, and 2.5-fold higher than arbutin, respectively. In particular, DBLS-21 and -33 was 112.8- and 6.1-fold higher than arbutin, respectively (293.4 μM) on tyrosinase inhibition activity (IC_5_0 ). But DBLS-24 had no tyrosinase inhibitory activity. These results suggest that cysteine derivatives possess potential for use as an antioxidant agent (DBLS-21) and whitening agents (all derivatives) in cosmetics

  4. New algorithms derived from the synthesis method. Application to diffusion problems

    International Nuclear Information System (INIS)

    Rouzaud, Philippe.

    1976-05-01

    Two algorithms to compute the neutron distribution in a nuclear reactor are presented. These algorithms, the iterative synthesis method (MSI) and the synthesis method by deflation (MSD), are derived from the classical synthesis method (MSC). They retain the most important advantages of MSC (computing time and memory storage reduced with regard to finite difference methods) and avoid its drawbacks: choice of trial functions; choice of weighting functions; choice of the number of terms (for MSD only). Extensive numerical checks of the three methods (MSC, MSI, MSD) were carried out on two fast reactor configurations described in plane geometry (X,Y). Monoenergetic and multigroup theories were successively used. The use of MSI and MSD allows a significant reduction of the discrepancies between the finite difference method and the synthesis method for the reactivity values and the flux distribution [fr

  5. H3-THYMIDINE DERIVATIVE POOLS IN RELATION TO MACRONUCLEAR DNA SYNTHESIS IN TETRAHYMENA PYRIFORMIS

    Science.gov (United States)

    Stone, G. E.; Miller, O. L.; Prescott, D. M.

    1965-01-01

    The formation of a soluble H3-thymidine derivative pool has been examined in Tetrahymena pyriformis as a function of macronuclear DNA synthesis during the cell life cycle. An autoradiographic technique which allows the detection of water-soluble materials within a cell has shown that these cells do not take up and retain exogenous H3-thymidine during G1 or G2. Uptake of H3-thymidine is restricted to the S period of the cell cycle. Additional autoradiographic experiments show, however, that a soluble pool of H3-thymidine derivatives persists from the end of one DNA synthesis period to the beginning of the next synthesis period in the subsequent cell cycle. Since this persisting pool cannot be labeled with H3-thymidine, the pool does not turn over during non-S periods. PMID:19866660

  6. Ozone Synthesis Efficiency Upgrading in the Pulsed Point-to-Plane Gas Discharge

    International Nuclear Information System (INIS)

    Golota, V.I.; Zavada, L.M.; Kotyukov, O.V.; Polyakov, A.V.; Pugach, S.G.

    2006-01-01

    Results are reported from the studies into electrodynamic characteristics of the barrierless point-to-plane gas discharge as a HV pulse of positive polarity is applied to the point electrode. The efficiency of ozone synthesis has been determined as a function of the length and repetition frequency of the HV pulse. It has been demonstrated that the electrodynamic characteristics of the discharge and the efficiency of ozone synthesis in oxygen-containing gas mixtures essentially depend on the parameters of HV power supply. The HV switch HTS-300 (BEHLKE Electronic GmbH) was used for HV pulse shaping

  7. The direct conversion of synthesis gas to chemicals / Ernest du Toit

    OpenAIRE

    Du Toit, Ernest

    2002-01-01

    The catalytic conversion of synthesis gas, obtainable from the processing of coal, biomass or natural gas, to a complex hydrocarbon product stream can be achieved via the Fischer-Tropsch process. The Fischer-Tropsch synthesis process has evolved from being mainly a fuel producing process in the early 1950's to that of a solvent and speciality wax production process towards the end of the 1970's. From the early 1980's there has been a clear shift towards the production of commod...

  8. Synthesis and properties of highly branched Jatropha curcas L. oil derivatives

    NARCIS (Netherlands)

    Daniel, Louis; Ardiyanti, Agnes R.; Schuur, Boelo; Manurung, Robert; Broekhuis, Antonius A.; Heeres, Hero J.

    The synthesis and properties of a number of novel branched Jatropha curcas L. oil (JO) derivatives containing vicinal di-ester units in the fatty acid chains are reported. Both the length (acetyl vs. hexanoyl) and the stereochemistry of the vicinal di-ester units (cis vs. trans) were varied. The

  9. Synthesis of Alkyne and Alkene Ketal Derivatives of Pentacyclo[5.4 ...

    African Journals Online (AJOL)

    NICO

    2013-11-04

    phenyl-pentacyclo[5.4.0.02,6.03,10.05,9]undecane-8-11-one can be easily accomplished by using the alcohols of various alkynes and alkenes. Generally the synthesis of terminal alkyne and cyclic alkene ketal derivatives were ...

  10. Synthesis of acetylene alcohols of heterocyclic type and the acyl derivatives

    Directory of Open Access Journals (Sweden)

    Moldir Dyusebaeva

    2015-03-01

    Full Text Available A synthesis of potentially biologically active heterocyclic amino alcohols of acetylene (Piperidine and Morpholine under the conditions of Mannich reaction accomplished and received their acyl derivatives. Pharmacological activity (antibacterial and antispasmotic of synthesized compounds, also acute toxicological characteristics studied. The study showed that the combination of DMAE-4 has antispasmodic activity with low toxicity.

  11. Synthesis of novel derivatives of 5-hydroxymethylcytosine and 5-formylcytosine as tools for epigenetics

    Directory of Open Access Journals (Sweden)

    Anna Chentsova

    2014-01-01

    Full Text Available In this work we present for the first time the synthesis of novel 5-hydroxymethylcytosine (5hmC and 5-formylcytosine (5fC derivatives that can be used as tools in the emerging field of epigenetics for deciphering chemical biology of TET-mediated processes.

  12. Chemically Modified Starch; Allyl- and Epoxy-Starch Derivatives: Their Synthesis and Characterization

    NARCIS (Netherlands)

    Franssen, M.C.R.; Boeriu, C.

    2014-01-01

    Both native and modified starches, such as starch that is pregelatinized, extruded, acid-converted, cross-linked, and substituted, are widely used in industry. This chapter describes a mild two-step process for the synthesis of novel, highly reactive granular epoxy-starch derivatives. Via this

  13. Synthesis of 2-vinylic indoles and derivatives via a Pd-catalyzed tandem coupling reaction.

    Science.gov (United States)

    Fayol, Aude; Fang, Yuan-Qing; Lautens, Mark

    2006-09-14

    A novel one-step synthesis of valuable 2-vinylic indoles and their tricycle derivatives is described. This reaction, which utilizes a gem-dibromovinyl unit as a readily available starting material, occurs via an efficient Pd-catalyzed tandem Buchwald-Hartwig/Heck reaction.

  14. Multicomponent Reaction in Ionic Liquid: A Novel and Green Synthesis of 1, 4-Dihydropyridine Derivatives

    Institute of Scientific and Technical Information of China (English)

    Xin Ying ZHANG; Yan Zhen LI; Xue Sen FAN; Gui Rong QU; Xue Yuan HU; Jian Ji WANG

    2006-01-01

    An efficient and green method for the synthesis of 1, 4-dihydropyridine derivatives mediated in an ionic liquid, [bmim][BF4], through a four-component condensation process of aldehydes, 1, 3-dione, Meldrum's acid and ammonium acetate is disclosed in this paper.

  15. Synthesis and X-ray structure of the dysprosium(III) complex derived ...

    African Journals Online (AJOL)

    Synthesis and X-ray structure of the dysprosium(III) complex derived from the ligand 5-chloro-1 ... Bulletin of the Chemical Society of Ethiopia ... synthesized and its crystal structure determined by single X-ray diffraction at room temperature.

  16. Silica Sulfuric Acid: An Eco-Friendly and Reusable Catalyst for Synthesis of Benzimidazole Derivatives

    Directory of Open Access Journals (Sweden)

    Bahareh Sadeghi

    2013-01-01

    Full Text Available Silica sulfuric acid (SiO2-OSO3H as an eco-friendly, readily available, and reusable catalyst is applied to benzimidazole derivatives synthesis under reflux in ethanol. The procedure is very simple and the products are isolated with an easy workup in good-to-excellent yields.

  17. Natural gas adsorption on biomass derived activated carbons: A mini review

    Directory of Open Access Journals (Sweden)

    Hamza Usman D.

    2016-01-01

    Full Text Available Activated carbon materials are good candidates for natural gas storage due excellent textural properties that are easy to enhance and modify. Natural gas is much cleaner fuel than coal and other petroleum derivatives. Storage of natural gas on porous sorbents at lower pressure is safer and cheaper compared to compressed and liquefied natural gas. This article reviews some works conducted on natural gas storage on biomass based activated carbon materials. Methane storage capacities and deliveries of the various sorbents were given. The effect of factors such as surface area, pore characteristic, heat of adsorption, packing density on the natural gas storage capacity on the activated carbons are discussed. Challenges, improvements and future directions of natural gas storage on porous carbonaceous materials are highlighted.

  18. Synthesis, characterization and pharmacological evaluation of substituted phenoxy acetamide derivatives

    Directory of Open Access Journals (Sweden)

    Rani Priyanka

    2015-01-01

    Full Text Available A novel series of 2-(substituted phenoxy-N-(1,7,7-trimethylbicyclo[2.2.1]heptan-2-ylacetamide and N-(2-bromocyclohexyl-2-(substituted phenoxyacetamide derivatives having cyclohexyl nucleus as common in both types were synthesized and assessed for their anti-inflammatory activity by a carrageenan induced rat paw oedema method, analgesic activity by Eddy’s hot plate method and antipyretic activity by brewer’s yeast induced pyrexia method. All the novel derivatives have been synthesized by the reaction of camphor and similar ketone having cyclohexane nucleus (e.g. 2-bromocyclohexanone with ammonium carbonate and formic acid resulting in the formation of aromatic amines (1a-b. These amines on further chloroacetylation with chloroacetylchloride give compounds (2a-b. Compounds (2a-b are converted to 2-(substituted phenoxy-N-(1,7,7-trimethylbicyclo[2.2.1]heptan-2-yl acetamide and N-(2-bromocyclohexyl-2-(substituted phenoxyacetamide derivatives on treatment with substituted phenol. Among the series 3a-f, 3i, 3k, 3l compounds showed significant anti-inflammatory activity as compared to the standard drug diclofenac sodium and also compound 3a-f, 3h, 3j, 3k exhibit significant analgesic activity as compared to the standard drug. Compounds 3a-f and 3k showed antipyretic activity nearly to the standard drug indomethacin. Compounds 3a-f and 3k possess anti-inflammatory, analgesic and antipyretic activities near to the standard.

  19. Synthesis of novel ionic liquids from lignin-derived compounds

    Science.gov (United States)

    Socha, Aaron; Singh, Seema; Simmons, Blake A.; Bergeron, Maxime

    2017-09-19

    Methods and compositions are provided for synthesizing ionic liquids from lignin derived compounds comprising: contacting a starting material comprising lignin with a depolymerization agent to depolymerize the lignin and form a mixture of aldehyde containing compounds; contacting the mixture of aldehyde containing compounds with an amine under conditions suitable to convert the mixture of aldehyde containing compounds to a mixture of amine containing compounds; and contacting the mixture of amine containing compounds with an acid under conditions suitable to form an ammonium salt, thereby preparing the ionic liquid.

  20. Synthesis and Anticancer Activities of Glycyrrhetinic Acid Derivatives

    Directory of Open Access Journals (Sweden)

    Yang Li

    2016-02-01

    Full Text Available A total of forty novel glycyrrhetinic acid (GA derivatives were designed and synthesized. The cytotoxic activity of the novel compounds was tested against two human breast cancer cell lines (MCF-7, MDA-MB-231 in vitro by the MTT method. The evaluation results revealed that, in comparison with GA, compound 42 shows the most promising anticancer activity (IC50 1.88 ± 0.20 and 1.37 ± 0.18 µM for MCF-7 and MDA-MB-231, respectively and merits further exploration as a new anticancer agent.

  1. Synthesis and Analgesic Activity Evaluation of Some Agmatine Derivatives

    Directory of Open Access Journals (Sweden)

    Song Li

    2006-06-01

    Full Text Available A series of N,N’-disubstituted-2-nitroethene-1,1-diamine and N,N’-disubstituted- N’’-cyanoguanidine derivatives were prepared and evaluated for in vivo analgesic activity. The blood brain barrier (BBB VolSurf model was used to predict the BBB permeation profiles of our synthesized compounds. Some compounds show both remarkable analgesic activity and good BBB permeation profiles, and these compounds might be developed for treatment of opioid tolerance and dependence.

  2. Synthesis, antimicrobial and antioxidative activity of some new isatin derivatives

    Directory of Open Access Journals (Sweden)

    Šekularac Gavrilo M.

    2014-01-01

    Full Text Available The isatin derivatives, Schiff bases, were synthesized by the reaction of isatin and various substituted primary amines and characterized by several spectroscopic methods. Investigation of the antimicrobial activity of the synthesized compounds was performed by the agar dilution method, against different strains of bacteria and one fungi. The antioxidative activity of the synthesized compounds was also determined. Some of the compounds have shown the significant activity against the selected strains of microorganisms and the antioxidative activity. [Projekat Ministarstva nauke Republike Srbije, br. 172013 i III 46010

  3. Synthesis and Analgesic Properties of Lidocaine Derivatives with Substituted Aminobenzothiazoles.

    Science.gov (United States)

    Ahmadi, Abbas; Khalili, Mohsen; Mohammadinoude, Mohammad Kazem; Nahri-Niknafs, Babak

    2016-01-01

    Local anesthetics are the most widely consumed drugs in the practice of medicine which provide a loss of sensation in a certain body part without loss of consciousness or impairment of central control of essential functions. Lidocaine (I) is the most commonly local anaesthetic drug which is widely used in all species due to its fabulous diffusing and penetrating properties as well as prompt onset of surgical analgesia. In this study, new aminobenzothiazole (with many useful biological and pharmacological properties) analogues were synthesized by changing of amine moiety of I. Both acute and chronic pain properties of new compounds (II-VI) were studied by using the tail immersion and formalin tests on mice and the outcomes were compared with control and lidocaine groups. According to the results, aminobenzothiazole derivatives are better candidates than diethylamine group for replacement on amine moiety of I. Also, derivatives with electron-withdrawing groups on this amine (V and VI) could decrease pain better than electron-donating ones (II and III) (specially on position 6 of this amine, II and V) which may be of concern for blockade of specific sodium channels by these new compounds.

  4. Synthesis and Antidepressant Activity Profile of Some Novel Benzothiazole Derivatives

    Directory of Open Access Journals (Sweden)

    Ümide Demir Özkay

    2017-09-01

    Full Text Available Within the scope of our new antidepressant drug development efforts, in this study, we synthesized eight novel benzothiazole derivatives 3a–3h. The chemical structures of the synthesized compounds were elucidated by spectroscopic methods. Test compounds were administered orally at a dose of 40 mg/kg to mice 24, 5 and 1 h before performing tail suspension, modified forced swimming, and activity cage tests. The obtained results showed that compounds 3c, 3d, 3f–3h reduced the immobility time of mice as assessed in the tail suspension test. Moreover, in the modified forced swimming tests, the same compounds significantly decreased the immobility, but increased the swimming frequencies of mice, without any alteration in the climbing frequencies. These results, similar to the results induced by the reference drug fluoxetine (20 mg/kg, po, indicated the antidepressant-like activities of the compounds 3c, 3d, 3f–3h. Owing to the fact that test compounds did not induce any significant alteration in the total number of spontaneous locomotor activities, the antidepressant-like effects of these derivatives seemed to be specific. In order to predict ADME parameters of the synthesized compounds 3a–3h, some physicochemical parameters were calculated. The ADME prediction study revealed that all synthesized compounds may possess good pharmacokinetic profiles.

  5. Synthesis and antimicrobial activities of 9H-carbazole derivatives

    Directory of Open Access Journals (Sweden)

    Nadia Salih

    2016-09-01

    Full Text Available In this work 9H-carbazole was utilized as a precursor to prepare new heterocyclic derivatives. Treatment of carbazole 1 with ethyl acetoacetate gave ethyl 9H-carbazol-9-ylacetate 2. The acetate ester derivative 2 was transformed into the 2-(9H-carbazol-9-ylacetohydrazide 3 through treatment with hydrazine hydrate. Reaction of compound 3 with sodium nitrite/HCl afforded [(9H-carbazol-9-ylacetylamino]diazonium chloride 4. Compounds 3-[3-(9H-carbazol-9-ylacetyltriazanylidene]pentane-2,4-dione 5 and ethyl 2-[3-(9H-carbazol-9-ylacetyltriazanylidene]-3-oxobutnoate 6 were obtained by reaction of compound 4 with acetylacetone and ethyl acetoacetate, respectively. Treatment of compounds 5 and 6 with urea and phenylhydrazine afforded 5-[3-(9H-carbazol-9-ylacetyltriazanylidene]-4,6-dimethyl pyrimidin-2(5H-one 7 and 4-[3-(9H-carbazol-9-yl acetyltriazanylidene]-5-methyl-2-phenyl-2,4-dihydro-3H-pyrazol-3-one 8, respectively. The structures of the synthesized compounds were characterized by IR, 1H NMR, 13C NMR and elemental analysis. All synthesized products were tested and evaluated as antimicrobial agents.

  6. Synthesis and photophysical properties of indium(III) phthalocyanine derivatives

    Energy Technology Data Exchange (ETDEWEB)

    Özceşmeci, İbrahim, E-mail: ozcesmecii@itu.edu.tr [Department of Chemistry, Technical University of Istanbul, Maslak 34469, Istanbul (Turkey); Gelir, Ali [Department of Physics, Technical University of Istanbul, Maslak 34469, Istanbul (Turkey); Gül, Ahmet [Department of Chemistry, Technical University of Istanbul, Maslak 34469, Istanbul (Turkey)

    2014-03-15

    Three chloroindium(III) phthalocyanine derivatives bearing four aromatic (naphthalene or pyrene) or aliphatic (hexylthio) groups were prepared from corresponding phthalonitrile compounds. The indium(III) phthalocyanine derivatives were characterized with elemental analyses, mass, proton nuclear magnetic resonance ({sup 1}H NMR), Fourier transform infrared spectroscopy (FT-IR) and ultraviolet–visible spectroscopy (UV–vis) techniques. Quantum yields and the energy transfer from the substituents to phthalocyanine core were examined. No energy transfer was observed for 5. The energy transfer efficiency from pyrene units to indium phthalocyanine core was calculated as 0.27 for 6. Quantum yields of all samples were very small due to heavy atom effect of indium atom in the core. It was also observed that upon binding of pyrene and naphthalene units to indium phthalocyanine as substituents, the quantum yields of indium phthalocyanine parts of 5 and 6 decreased. -- Highlights: • Three chloroindium(III) phthalocyanines were prepared and characterized. • Aggregation properties of these compounds were investigated. • The energy transfer efficiency was examined. • Quantum yield of these systems were calculated.

  7. Synthesis and pharmacological activity evaluation of arctigenin monoester derivatives.

    Science.gov (United States)

    Chen, Qiulian; Yang, Limin; Han, Mei; Cai, Enbo; Zhao, Yan

    2016-12-01

    Arctigenin (ARG), a nature medicine with many pharmacological activities, was poorly soluble in water and placed restriction on practical usage. Six novel arctigenin monoester derivatives were obtained from the reflux reaction with arctigenin, carboxylic acids (crotonic acid, furoic acid, 2-naphthalene acid and indol-3-acetic acid), EDCI and DMAP in dichloromethane at 60°C for 4-6h and their properties on nitrite scavenging assay were investigated in vitro. Based on the results, the one of the most effective derivatives, arctigenin β-indolylacetate (ARG6), was selected to study anti-tumor activity in vivo at doses of 20 and 40mg/kg. The results showed that comparison with ARG group, ARG6 exhibited more anti-tumor activity in H22 tumor-bearing mice. Furthermore, ARG6 exhibited less damage to the liver, kidney, spleen and thymus when compared with those in positive group. Biochemical parameters of ALT, AST, BUN and Cre showed ARG6 had little toxicity to mice as well. ARG6 significantly improved serum cytokine levels of IL-2, IL-6, IFN-γ and TNF-α, and decreased VEGF compared with ARG. Moreover, H & E staining, TUNEL assay and immunohistochemical of tumor issues also indicated that ARG6 exhibited anti-tumor activity in vivo. In brief, the present study provide a method to improve ARG anti-tumor activity and provide a reference for new anti-tumor agent. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  8. Design, Synthesis and Fungicidal Activities of Some Novel Pyrazole Derivatives

    Directory of Open Access Journals (Sweden)

    Xue-Ru Liu

    2014-09-01

    Full Text Available In order to discover new compounds with good fungicidal activities, 32 pyrazole derivatives were designed and synthesized. The structures of the target compounds were confirmed by 1H-NMR, 13C-NMR, and high-resolution electrospray ionization mass spectrometry (HR-ESI-MS, and their fungicidal activities against Botrytis cinerea, Rhizoctonia solani Kuhn, Valsa mali Miyabe et Yamada, Thanatephorus cucumeris (Frank Donk, Fusarium oxysporum (S-chl f.sp. cucumerinum Owen, and Fusarium graminearum Schw were tested. The bioassay results indicated that most of the derivatives exhibited considerable antifungal activities, especially compound 26 containing a p-trifluoromethyl- phenyl moiety showed the highest activity, with EC50 values of 2.432, 2.182, 1.787, 1.638, 6.986, and 6.043 μg/mL against B. cinerea, R. solani, V. mali, T. cucumeris, F. oxysporum, and F. graminearum, respectively. Moreover, the activities of compounds such as compounds 27–32 were enhanced by introducing isothiocyanate and carboxamide moieties to the 5-position of the pyrazole ring.

  9. Synthesis, physicochemical and biological properties of ethynyl piperidol derivatives

    International Nuclear Information System (INIS)

    Khalikov, D.Kh.

    2012-01-01

    The book presents the results of studies on the reactivity of some derivatives of ethynyl-piperidol in reactions of homo-and copolymerization, the numerical values of the constants of the initiation reaction, growth and chain termination, the parameters of molecular weight, molecular weight distribution and flexibility of polymer chins, triple-radical copolymerization results of ethynyl-piperidol derivatives with hydrophilic monomers and polyfunctional cross-linked polymers and high swelling hydrogels, as well as developed by the author the radiation-chemical grafting technique termed monomers on the surface of cellulose in a continuous manner. The experimental data on ethynyl-piperidol polymers involves with various low-, medium-and high substrates from model solutions and in biological fluids are given. On the example of three iodide ion sorption, bilirubin and serum albumin showed that for the thermodynamically favorable process make a significant contribution to the free energy terms due to the hypothetical ion exchange, the change in resonates concentration and cooperative interaction. The role of hydrophobic interaction in realization of this process is reviled. The data obtained were formulated and validated a number of scientific statements in the chemistry of biomedical polymers. The results of the practical implementation of a number of developments in medical practice are demonstrated. The hydrogel homo-and sorbent, dressings, which have shown high efficacy in the treatment of diseases complicated by endogenous and bacterial endotoxemia in acute radiation and combined radiation-thermal lesions, as well as kidney and live failure. (author)

  10. Synthesis, spectroscopic characterization and pharmacological evaluation of oxazolone derivatives

    Directory of Open Access Journals (Sweden)

    Fareed Ghulam

    2013-01-01

    Full Text Available A series of 4-aryl methylidene-2-phenyl/methyl-5-(4H-oxazolone derivatives (2-7 have been synthesized using the reported method by condensation of aldehydes with N-benzoyl / N-acetyl glycine in the presence of zinc oxide as a catalyst and acetic anhydride at room temperature in ethanol. The compounds (2-6 are new derivatives. The structures of compounds were evaluated on the basis of 1H-NMR, 13C-NMR, EIMS, FT-IR and elemental analysis. All the compounds were screened for their antibacterial and urease inhibition activity. Antibacterial activity was tested by agar well diffusion method using Mueller Hinton Agar medium. Compound (2 showed excellent activity against S. aureus which has 16 mm (80% inhibition and above 24 mm (70% against S. typhi. The most active compound against E. coli was compound (6 having 20 mm (80% inhibition followed by compound (5 having above 18 mm (70% inhibition. Urease inhibition activity of all the compounds was determined by indophenol method. Compounds (3, 6 and (7 showed significant inhibition against Jacks bean urease.

  11. Enaminone in heterocyclic synthesis: synthesis of new pyrazolopyrazole, pyrazolothienooxazine and pyrazolothienopyridine derivatives

    International Nuclear Information System (INIS)

    Hafiz, I.S.; Rahim, M.A.M.A.

    2014-01-01

    The chemical reactivity of enaminone 2 toward some nucleophilic and electrophilic reagents was investigated. Enaminone 2 was used as a key precursor for the synthesis of many important heterocyclic compounds. The synthesized compounds were characterized by IR, 1H-NMR, MS spectral and elemental analysis. (author)

  12. Phosphorylated derivatives of anabasine: synthesis, constitution and complex forming properties

    International Nuclear Information System (INIS)

    Babaev, B.N.

    2004-01-01

    Full text: With the purpose of detection of new effective extra gents of metals from number of sulphur containing derivatives of acids of phosphorus with different functional groups, analysis of effect of the different factors on selectivity of allocation of metals, installation of optimum conditions of an extraction, the detections of effective extra gents of noble metals from industrial sewage waters, are synthesized phosphorylated derivatives of the anabasine - O-alkyl-O-(anaba-sinoisopropyl)- and O-alkyl-O-(anabasinobutyn-2-yl)phenyl phosphonates and O-(anabasinoisopropyl)- and O-(anabasinobutyn-2-yl)diphenyl phosphonates In an IR-spectrum about O-pentyl-O-[anabasinoisopropyl]phenylphosphonate There are absorption band of the following functional groups (ν, cm -1 ): (P-O-C 5 H 11 ) 990-1000, (P = 0) 1250, (P-C 6 H 5 )1450, (C-N in cycle) 1550. In a spectrum PMR O-(anabasinobutyn-2-yl)phenylphosphonate in the field of a weak field apart from signals of two phenylic radicals the signals of a b-displaced pyridine, reference for a molecule anabasine are observed: Hαa-8,46 p.m., H α '-8,41 p.m., H γ -7,60 p.m. And H β -7,15 p.m. A double triplet at 4,70 p.m. And triplet at 3,05 p.m. Belong to signals OCH 2 and N-CH 2 of groups, accordingly, separated by acetylene bond. The signals of piperidine cycle of anabasine have the following chemical shifts: H 2a -3,27 p.m., H 6e -2,78 p.m., H 6a -2,45 p.m., and remaining protons (6H, m, CH 2 ) are in resonance in the field of 1,1-1,9 p.m. The analysis of mass-spectrometer decay of the synthesized connections has shown, that the mass-spectrometer fragmentation M * about - O-alkyl-O- (anabasinoisopropyl) phenylphosphonates flows past in different directions and is characterized, as against about O-alkyl-O-(anabasinobutyn-2-yl)phenyl-phosphonates, large number of phosphor containing ions; the availability of the second phenylic radical in molecules anabasincontaining derivatives of a diphenyl phosphinic acid essentially

  13. Synthesis and evaluation of the antiplasmodial activity of tryptanthrin derivatives

    Directory of Open Access Journals (Sweden)

    Liliane Abodo Onambele

    2015-08-01

    Full Text Available Malaria remains one of the most deadly diseases threatening humankind and is still affecting a significant proportion of the world population, especially in Africa. Chemotherapy is a vital component of the fight against the disease and new antimalarial agents are urgently needed to curb the spread of malaria parasites that are resistant to existing drugs. The natural product tryptanthrin is known for its wide range of activities, including antiplasmodial activity, but its poor solubility has undermined its development as potent antimicrobial and antiprotozoan agent. The aim of this work was to synthesize analogues of tryptanthrin and to evaluate their antiplasmodial activity against the asexual and sexual blood stages of Plasmodium falciparum. Our results suggest that most tryptanthrin analogues retained their antiplasmodial activity against chloroquine-sensitive and chloroquine-resistant malaria parasites in the nanomolar range (30–100 nM. The antiplasmodial activity of the most active compound NT1 (IC50: 30 nM; SI: 155.9 was similar in both strains and close to that of chloroquine (IC50: 20 nM on the sensitive strain. The antiplasmodial activity was improved with derivatization, thus pointing out the necessity to explore tryptanthrin using medicinal chemistry approaches. Ten (10 of the tested derivatives met the criteria, allowing for advancement to animal testing, i.e., SI > 100 and IC50 < 100 nM. In addition to their activity on the asexual stages, tryptanthrin and two selected derivatives (NT1 and T8 prevented the maturation of gametocytes at their IC90 concentrations, indicating a transmission-blocking potential. Moreover, NT1 was able to impair gametogenesis by reducing the exflagellation of microgametes by 20% at IC90, while tryptanthrin and T8 had no influence on exflagellation. The results of this study confirm that tryptanthrin and its derivatives are potential antimalarial candidates with abilities to kill the

  14. Synthesis and characterization of a novel mucoadhesive derivative of xyloglucan.

    Science.gov (United States)

    Madgulkar, Ashwini R; Bhalekar, Mangesh R; Asgaonkar, Kalyani D; Dikpati, Amrita A

    2016-01-01

    A novel polymer in the form of a thiolated derivative of natural tamarind seed polysaccharide or xyloglucan was synthesized and its chacteristics as a mucoadhesive polymer were studied as a part of the study undertaken herein. The synthetic route followed involves a two-step reaction mechanism of firstly oxidizing xyloglucan and then further conjugating it with l-cysteine to form thiolated xyloglucan or thiomer via imine linkage. The thiomer thus formed was characterized using various analytical techniques as differential scanning calorimetry (DSC), X-ray diffraction analysis (XRD), and nuclear magnetic resonance (NMR). Ellman's method was used to determine the numbers of thiol groups/g of thiolated xyloglucan. Zeta potential measurements were carried out for thiolated xyloglucan. Viscosities of the formulated xyloglucan and thiolated xyloglucan gels were comparatively evaluated along with the evaluation of mucoadhesive properties of the gels using ex vivo bioadhesion study employing freshly excised sheep intestinal mucosa. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Synthesis and Herbicidal Activity of New Hydrazide and Hydrazonoyl Derivatives

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    František Šeršeň

    2015-08-01

    Full Text Available Three new hydrazide and five new hydrazonoyl derivatives were synthesized. The chemical structures of these compounds were confirmed by 1H-NMR, IR spectroscopy and elemental analysis. The prepared compounds were tested for their activity to inhibit photosynthetic electron transport in spinach chloroplasts and growth of the green algae Chlorella vulgaris. IC50 values of these compounds varied in wide range, from a strong to no inhibitory effect. EPR spectroscopy showed that the active compounds interfered with intermediates Z•/D•, which are localized on the donor side of photosystem II. Fluorescence spectroscopy suggested that the mechanism of inhibitory action of the prepared compounds possibly involves interactions with aromatic amino acids present in photosynthetic proteins.

  16. Lipophilic phytosterol derivatives: synthesis, thermal property and nanoemulsion behavior

    DEFF Research Database (Denmark)

    Panpipat, Worawan; Xu, Xuebing; Guo, Zheng

    Phytosterols and their esters have been reported as a cholesterol lowering agent in human. However, natural phytosterols have a low solubility in both water and fat resulting in a poor absorption in intestine. To improve the intestinal absorption and bioavailability of phytosterols, conversion...... of phytosterols into enzyme-liable lipophilic derivatives, such as fatty acid esters was one of the possible strategies. Differences in molecular structures of modified phytosterols may result in the differences in their thermal and micelling behaviors. Therefore, the objectives of this study were to improve...... the productive yield of a series of -sitosteryl fatty acid esters (C2-C18) and to investigate the thermal property and nano-emulsion behaviors of those compounds. This work reported a novel approach to synthesize phytosterol (-sitosterol as a model) fatty acid ester by employing Candida antarctica lipase...

  17. Synthesis and Biological Evaluation of Some Novel Dithiocarbamate Derivatives

    Directory of Open Access Journals (Sweden)

    Begüm Nurpelin Sağlık

    2014-01-01

    Full Text Available 18 novel dithiocarbamate derivatives were synthesized in order to investigate their inhibitory potency on acetylcholinesterase enzyme and antimicrobial activity. Structures of the synthesized compounds were elucidated by spectral data and elemental analyses. The synthesized compounds showed low enzyme inhibitory activity. However, they displayed good antimicrobial activity profile. Antibacterial activity of compounds 4a, 4e, and 4p (MIC = 25 μg/mL was equal to that of chloramphenicol against Klebsiella pneumoniae (ATCC 700603 and Escherichia coli (ATCC 35218. Most of the compounds exhibited notable antifungal activity against Candida albicans (ATCC 10231, Candida glabrata (ATCC 90030, Candida krusei (ATCC 6258, and Candida parapsilosis (ATCC 7330. Moreover, compound 4a, which carries piperidin-1-yl substituent and dimethylthiocarbamoyl side chain as variable group, showed twofold better anticandidal effect against all Candida species than reference drug ketoconazole.

  18. Synthesis, radioiodination and biological evaluation of a novel phthalimide derivative

    International Nuclear Information System (INIS)

    Motaleb, M.A.; Abdel-Ghaney, I.Y.; Shamsel-Din, H.A.; Abdel-Bary, H.M.

    2016-01-01

    Biologically active novel phthalimide derivative, N-(5-(2-hydroxyphenyl)-4,5-dihydro-1H-pyrazol-3-yl)phthalimide (HPZPHT), was synthesized in excellent yield and characterized by IR, mass and 1 H NMR spectroscopy. It was radiolabeled with iodine-131 by direct electrophilic substitution reaction and radiochemical yield was determined by using different chromatographic techniques (HPLRC, paper chromatography and paper electrophoresis). 131 I-HPZPHT has high radiolabeling yield (98.00 ± 2.00 %), stability, solid tumor uptake and T/NT ratio (5.17 ± 0.03 at 30 min. post-injection) compared with many new tracers which have been developed in recent years. This study encourages the possible use of this tracer as a potential imaging and/or therapeutic agent for cancer. (author)

  19. Synthesis and anti-depressant evaluation of novel pyrazolone derivatives

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    Vijay Kumar Merugumolu

    2016-06-01

    Full Text Available Diazotization of substituted anilines with NaNO2 and concentrated hydrochloric acid at 0ºC gave the diazonium chlorides. Coupling of substituted aryl diazonium chlorides with ethyl acetoacetate in methanol gave ethyl-2-aryl-hydrazono-3-oxobutyrates (2a-h. Reaction of (2a-h with naphthoic carbohydrazide (3 gave the title compounds pyrazolone derivatives (4a-h. The newly synthesized compounds were screened for their in vivo anti-depressant activity by tail suspension test and forced swimming test. Some of the tested compounds 4f, 4g showed very good activity when compared to the standard drug imipramine. The newly synthesized compounds were characterized by physical parameters and the structures were elucidated by spectral data.

  20. Synthesis and Antimicrobial Characterization of Half-Calycanthaceous Alkaloid Derivatives

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    Shaojun Zheng

    2016-09-01

    Full Text Available A total of 29 novel tetrahydropyrroloindol-based calycanthaceous alkaloid derivatives were synthesized from indole-3-acetonitrile in good yields. The synthesized compounds were evaluated against nine strains of bacteria and a wide range of plant pathogen fungi. Bioassay results revealed that majority of the compounds displayed similar or higher in vitro antimicrobial activities than the positive control. The biological activities also indicated that substituents at R4 and R5 significantly affect the activities. Notably, compound c4 was found to be most active among the tested calycanthaceous analogues and might be a novel potential leading compound for further development as an antifungal agent. The results could pave the way for further design and structural modification of calycanthaceous alkaloids as antimicrobial agents.

  1. Synthesis and antibacterial activity of some heterocyclic derivatives of sulfanilamide

    Directory of Open Access Journals (Sweden)

    B.B. Subudhi

    2012-12-01

    Full Text Available Considering the promising antimicrobial potential of carbonic anhydrase inhibitors and heterocyclic compounds some heterocyclic derivatives of sulfanilamide (2a-e were synthesized. The diazotisation of sulfanilamide followed by substitution with ethylacetoacetate and further condensation yielded compounds 2a-c. Schiff base of sulfanilamide with salicylaldehyde on reaction with thioglycollic acid and chloroacetyl chloride resulted in compound 2d-e. The susceptibility of Staphylococcus aureus, Enterococcus faecalis, Escherichia coli and Pseudomonas aeruginosa to the title compounds (300 μg/disc was investigated and compared to that of nitrofurantoin (300 μg/disc and ciprofloxacin (25 μg/disc. The title compounds showed good antimicrobial activity.DOI: http://dx.doi.org/10.4314/bcse.v26i3.15

  2. An efficient synthesis of tetramic acid derivatives with extended conjugation from L-Ascorbic Acid

    Directory of Open Access Journals (Sweden)

    Bisht Surendra S

    2006-12-01

    Full Text Available Abstract Background Tetramic acids with polyenyl substituents are an important class of compounds in medicinal chemistry. Both solid and solution phase syntheses of such molecules have been reported recently. Thiolactomycin, a clinical candidate for treatment of tuberculosis has led to further explorations in this class. We have recently developed an efficient synthesis of tetramic acids derivatives from L- ascorbic acid. In continuation of this work, we have synthesised dienyl tetramic acid derivatives. Results 5,6-O-Isopropylidene-ascorbic acid on reaction with DBU led to the formation of tetronolactonyl allyl alcohol, which on oxidation with pyridinium chlorochromate gave the respective tetranolactonyl allylic aldehydes. Wittig olefination followed by reaction of the resulting tetranolactonyl dienyl esters with different amines resulted in the respective 5-hydroxy lactams. Subsequent dehydration of the hydroxy lactams with p-toluene sulphonic acid afforded the dienyl tetramic acid derivatives. All reactions were performed at ambient temperature and the yields are good. Conclusion An efficient and practical method for the synthesis of dienyl tetramic acid derivatives from inexpensive and easily accessible ascorbic acid has been developed. The compounds bear structural similarities to the tetramic acid based polyenic antibiotics and thus this method offers a new and short route for the synthesis of tetramic acid derivatives of biological significance.

  3. Synthesis by plasma and characterization of compounds derived from polyacetylene

    International Nuclear Information System (INIS)

    Vasquez O, M.

    2004-01-01

    This work presents a study on, the synthesis by plasma and the characterization of an aliphatic conjugated polymer, polyacetylene-chlorinated (Pac), and two aromatic polymers, Poly pyrrole (P Py-Cl) and Poly thiophene (Pth-Cl) synthesized with chlorine and the electrical conductivity. The last two polymers were synthesized to compare the chlorine-polymer interaction in aliphatic and aromatic polymers synthesized by plasma and their repercussion on the electrical transport of charges in the material. The structure and morphology of the polymers were studied using scanning electron microscopy (Sem), energy dispersive spectroscopy (EDS), infrared spectroscopy (Ft-IR), conductivity analysis and X-Ray photon spectroscopy (XPS). The results showed that Pac is soluble in acetone and other organic solvents, which indicates a low proportion of crosslinking in the polymers. This point is important because the crosslinking reduces the electrical conductivity in the material. The Pac conductivity is in the range of 1 x 10 -12 to 6 x 10 -4 S/cm in the internal of 35- 90% of relative humidity. A possible mechanism for the transport of electrical charges in Pac is by means of the double and simple conjugated bonds in the polymers. Pth-Cl and P Py-Cl present electric conductivity in the interval of 9 x 10 -5 to 1 x 10 -2 S/cm and show a great dependence on the relative humidity. The chlorine addition in these polymers was through simultaneous polymerization with chloroform. This last compound can decompose if the energy of the plasma is relatively high, and the fragments can link to the polymer in a hybrid process of copolymerization. An important point of this work is that the polymer is soluble, a difference of the obtained via plasma as the poli aniline, P Py-CI and Pth-Cl both studied in this work. If took in account that the Pac is single the monomer and that P Py-Cl and Pth-CI is affected by the chlorine that modifies the conductivity of the material, then Pac presents an

  4. Microwave-assisted synthesis and antioxidant properties of hydrazinyl thiazolyl coumarin derivatives

    Directory of Open Access Journals (Sweden)

    Osman Hasnah

    2012-04-01

    Full Text Available Abstract Background Coumarin derivatives exhibit a wide range of biological properties including promising antioxidant activity. Furthermore, microwave-assisted organic synthesis has delivered rapid routes to N- and O-containing heterocycles, including coumarins and thiazoles. Combining these features, the use of microwave-assisted processes will provide rapid access to a targeted coumarin library bearing a hydrazino pharmacophore for evaluation of antioxidant properties Results Microwave irradiation promoted 3 of the 4 steps in a rapid, convergent synthesis of a small library of hydrazinyl thiazolyl coumarin derivatives, all of which exhibited significant antioxidant activity comparable to that of the natural antioxidant quercetin, as established by DPPH and ABTS radical assays Conclusions Microwave dielectric heating provides a rapid and expedient route to a series of hydrazinyl thiazolyl coumarins to investigate their radical scavenging properties. Given their favourable properties, in comparison with known antioxidants, these coumarin derivatives are promising leads for further development and optimization.

  5. Synthesis of Renewable meta-Xylylenediamine from Biomass-Derived Furfural.

    Science.gov (United States)

    Scodeller, Ivan; Mansouri, Samir; Morvan, Didier; Muller, Eric; de Oliveira Vigier, Karine; Wischert, Raphael; Jérôme, François

    2018-04-30

    We report the synthesis of biomass-derived functionalized aromatic chemicals from furfural, a building block nowadays available in large scale from low-cost biomass. The scientific strategy relies on a Diels-Alder/aromatization sequence. By controlling the rate of each step, it was possible to produce exclusively the meta aromatic isomer. In particular, through this route, we describe the synthesis of renewably sourced meta-xylylenediamine (MXD). Transposition of this work to other furfural-derived chemicals is also discussed and reveals that functionalized biomass-derived aromatics (benzaldehyde, benzylamine, etc.) can be potentially produced, according to this route. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Synthesis and characterization of porous silicon gas sensors

    Science.gov (United States)

    abbas, Roaa A.; Alwan, Alwan M.; Abdulhamied, Zainab T.

    2018-05-01

    In this work, photo-electrochemical etching process of n-type Silicon of resistivity(10 Ω.cm) and (100) orientation, using two illumination sources IR and violet wavelength in HF acid have been used to produce PSi gas detection device. The fabrication process was carried out at a fixed etching current density of 25mA/cm2 and at different etching time (5, 10, 15 and 20) min and (8, 16, 24, and 30) min. Two configurations of gas sensor configuration planer and sandwich have been made and investigated. The morphological properties have been studied using SEM,the FTIR measurement show that the (Si-Hx) and (Si-O-Si) absorption peak were increases with increasing etching time,and Photoluminescence properties of PSi layer show decrease in the peak of PL peak toward the violet shift. The gas detection process is made on the CO2 gas at different operating temperature and fixed gas concentration. In the planner structure, the gas sensing was measured through, the change in the resistance readout as a function to the exposure time, while for sandwich structure J-V characteristic have been made to determine the sensitivity.

  7. Hydantoin in heterocyclic synthesis: synthesis of new imidazopyridine imidazotriazole, pyrazolopurinone and imidazopyrazole derivatives

    International Nuclear Information System (INIS)

    Liu, M.; Li, X.

    2014-01-01

    A New series of imidazopyridine, imidazotriazole, pyrazolopurinone, pyranoimidazole, imidazopyridazine and imidazopyrazole derivatives were synthesized from the reaction of hydantion and its derivatives using a variety of electrophilic and nucleophilic reagents under mild conditions. The structures of the synthesized compounds were established via their elemental and spectral analyses. (author)

  8. Synthesis and Antimicrobial Activity of Sulfur Derivatives of Quinolinium Salts

    Directory of Open Access Journals (Sweden)

    Anna Empel

    2018-01-01

    Full Text Available A novel method for cleavage of the dithiine ring in 5,12-(dimethyl-thioqinantrenium bis-chloride 1 “via” reaction with sodium hydrosulfide leads to 1-methyl-3-mercaptoquinoline-4(1H-thione 2. Further transformation of thiol and thione functions of compound 2 leads to a series of sulfide and disulfide derivatives of quinolinium salts 4 and 6. 1-Methyl-4-chloro-3-benzylthioquinoline chloride 8 was obtained by N-alkylating 4-chloro-3-benzylthioquinoline using dimethyl sulfate. Antimicrobial activity of the obtained compounds was investigated using six Gram-positive and six Gram-negative bacterial strains, as well as Candida albicans yeast. Greater activity was demonstrated towards Gram-positive strains. MIC values for compounds and with benzylthio 4d and benzoylthio 4f substituents in 3-quinoline position were found to be in the 0.5–1 μg/mL range, at a level similar to that of ciprofloxacin (reference. Compounds 4d and 4f also demonstrated interesting antifungal properties (MIC = 1.

  9. Synthesis of New Cytotoxic Aminoanthraquinone Derivatives via Nucleophilic Substitution Reactions

    Directory of Open Access Journals (Sweden)

    Hasimah Alimon

    2013-07-01

    Full Text Available Aminoanthraquinones were successfully synthesized via two reaction steps. 1,4-Dihydroxyanthraquinone (1 was first subjected to methylation, reduction and acylation to give an excellent yield of anthracene-1,4-dione (3, 1,4-dimethoxyanthracene-9,10-dione (5 and 9,10-dioxo-9,10-dihydroanthracene-1,4-diyl diacetate (7. Treatment of 1, 3, 5 and 7 with BuNH2 in the presence of PhI(OAc2 as catalyst produced seven aminoanthraquinone derivatives 1a, b, 3a, and 5a–d. Amination of 3 and 5 afforded three new aminoanthraquinones, namely 2-(butylaminoanthracene-1,4-dione (3a, 2-(butylaminoanthracene-9,10-dione (5a and 2,3-(dibutylaminoanthracene-9,10-dione (5b. All newly synthesised aminoanthraquinones were examined for their cytotoxic activity against MCF-7 (estrogen receptor positive human breast and Hep-G2 (human hepatocellular liver carcinoma cancer cells using MTT assay. Aminoanthraquinones 3a, 5a and 5b exhibited strong cytotoxicity towards both cancer cell lines (IC50 1.1–13.0 µg/mL.

  10. Synthesis and reactions of triphenylphosphine-O-benzophenonimine and derivatives

    International Nuclear Information System (INIS)

    Elamin, Manahil Babiker

    1999-08-01

    O-Amino benzophenone and its para and meta isomers were prepared using Friedl-Craft benzoylation. Their azides were also prepared via their diazonium salts. The azide of o-amino benzophenone in its reduced form (o-benzylaniline) and its cyclic ketal were synthesised. All azides thus formed were reacted separately with triphenylphosphine to give the corresponding phosphinimines, the Wittig reagents nitrogen analog. The reactivity of the phosphorous bond. (P=N) in the different phosphoranes were studied by two types of reactions: (1) the Wittig type of reaction using benzaldehyde and its into derivatives with each of the above prepared phosphinimines. While triphenylphosphine-m-benzophenonimine (ii) and the triphenylphosphine benzophenonimine ethylene acetal (v) and it's reduced form triphenylphosphine-o-benzophenonimine (iv) react giving the corresponding schiffis bases. However, the ortho (i) and the para (iii) isomers failed to react. This lack of reactivity is presumably due to their great stability which came about through the extensive resonance that reduced the nucleophilicity of the nitrogen nucleophiles. (2) The phophinimines each was irradiated using Hanovia medium pressure UV lamp. Also the ortho and para isomers were not affected while others reacted giving the corresponding azo-compound and triphenylphosphine. they were separated and detected by chromatography.(Author)

  11. Synthesis and cytotoxicity evaluation of thiosemicarbazones and their thiazole derivatives

    Directory of Open Access Journals (Sweden)

    Saulo Feheiberg Pinto Braga

    Full Text Available ABSTRACT The aims of this study were to synthesize a series of thiosemicarbazones and their thiazole derivatives, to investigate their cytotoxic activity against three human cancers and normal (Vero cells cell lines, and to evaluate the pro-apoptotic potential of the most active compounds. Materials and Methods: The thiosemicarbazones were obtained by reacting an aromatic aldehyde with thiosemicarbazide (yield 71-96%, which were subjected to a cyclization with α-bromoacetophenone to yield the required thiazole heterocycles (yield 63-100%. All the synthesized compounds were screened at 50 µM concentration against three cell lines representing HL60 (promyelocytic leukemia, Jurkat (acute lymphoblastic leukemia, and MCF-7 (breast cancer. The pro-apoptotic effect was measured by flow cytometry as the percentage of cells with hypodiploid DNA. Results: Three thiazole compounds showed activity against at least one tumor cell line (IC50 = 43-76 µM and low cytotoxicity against Vero cells (IC50 > 100 M. The most active compound of this series induced 91% and 51% DNA fragmentation in HL60 and MCF-7 cell lines, respectively, suggesting that this compound triggered apoptosis in these cells. Conclusion: Among the synthesized compounds, one in particular was found to exert antiproliferative and pro-apoptotic activity on tumor cells and can be considered promising as a lead molecule for the design of new analogues with improved activity.

  12. Docking, synthesis and antimalarial activity of novel 4-anilinoquinoline derivatives.

    Science.gov (United States)

    Vijayaraghavan, Shilpa; Mahajan, Supriya

    2017-04-15

    A series of 4-anilinoquinoline triazine derivatives were designed, synthesized and screened for in vivo antimalarial activity against a chloroquine-sensitive strain of Plasmodium berghei. The compounds were further subjected to in vitro antimalarial activity against chloroquine-resistant W2 strain of Plasmodium falciparum and β-haematin inhibition studies. All the compounds exhibited in vivo antimalarial activity better than that shown by the standard drug, chloroquine. Twelve out of fifteen compounds showed better inhibition than that of chloroquine against chloroquine-resistant W2 strain of Plasmodium falciparum. Ten compounds showed β-haematin inhibition, better than that of chloroquine, with IC 50 values in the range of 18-25µM. One compound, 3k, was found to be better than artemisinin against W2 strain of Plasmodium falciparum and also displayed the best β-haematin inhibitory activity, thereby becoming eligible to be explored as a potential lead for antimalarial chemotherapy. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Efficient Synthesis and Bioactivity of Novel Triazole Derivatives.

    Science.gov (United States)

    Hu, Boyang; Zhao, Hanqing; Chen, Zili; Xu, Chen; Zhao, Jianzhuang; Zhao, Wenting

    2018-03-21

    Triazole pesticides are organic nitrogen-containing heterocyclic compounds, which contain 1,2,3-triazole ring. In order to develop potential glucosamine-6-phosphate synthase (GlmS) inhibitor fungicides, forty compounds of triazole derivatives were synthesized in an efficient way, thirty nine of them were new compounds. The structures of all the compounds were confirmed by high resolution mass spectrometer (HRMS), ¹H-NMR and 13 C-NMR. The fungicidal activities results based on means of mycelium growth rate method indicated that some of the compounds exhibited good fungicidal activities against P. CapasiciLeonian , Sclerotinia sclerotiorum (Lib.) de Bary, Pyricularia oryzae Cav. and Fusarium oxysporum Schl. F.sp. vasinfectum (Atk.) Snyd. & Hans. at the concentration of 50 µg/mL, especially the inhibitory rates of compounds 1-d and 1-f were over 80%. At the same time, the preliminary studies based on the Elson-Morgan method indicated that the compounds exhibited some inhibitory activity toward glucosamine-6-phosphate synthase (GlmS). These compounds will be further studied as potential antifungal lead compounds. The structure-activity relationships (SAR) were discussed in terms of the effects of the substituents on both the benzene and the sugar ring.

  14. Efficient Synthesis and Bioactivity of Novel Triazole Derivatives

    Directory of Open Access Journals (Sweden)

    Boyang Hu

    2018-03-01

    Full Text Available Triazole pesticides are organic nitrogen-containing heterocyclic compounds, which contain 1,2,3-triazole ring. In order to develop potential glucosamine-6-phosphate synthase (GlmS inhibitor fungicides, forty compounds of triazole derivatives were synthesized in an efficient way, thirty nine of them were new compounds. The structures of all the compounds were confirmed by high resolution mass spectrometer (HRMS, 1H-NMR and 13C-NMR. The fungicidal activities results based on means of mycelium growth rate method indicated that some of the compounds exhibited good fungicidal activities against P. CapasiciLeonian, Sclerotinia sclerotiorum (Lib. de Bary, Pyricularia oryzae Cav. and Fusarium oxysporum Schl. F.sp. vasinfectum (Atk. Snyd. & Hans. at the concentration of 50 µg/mL, especially the inhibitory rates of compounds 1-d and 1-f were over 80%. At the same time, the preliminary studies based on the Elson-Morgan method indicated that the compounds exhibited some inhibitory activity toward glucosamine-6-phosphate synthase (GlmS. These compounds will be further studied as potential antifungal lead compounds. The structure-activity relationships (SAR were discussed in terms of the effects of the substituents on both the benzene and the sugar ring.

  15. Synthesis and characterization of nanosized lithium manganate and its derivatives

    Science.gov (United States)

    Iqbal, Muhammad Javed; Zahoor, Sabia

    Spinel lithium manganese oxide, LiMn 2O 4 and its derivatives are prepared by the sol-gel method. The lattice constant of the pure material is calculated as 8.23 Å. Different transition metal cations of chromium, iron, cobalt, nickel, copper and zinc (0.05 and 0.15 M) are doped in place of manganese in the LiMn 2O 4. X-ray powder diffraction data show that the spinel framework preserved its integrity upon doping. Formation of a single phase and the purity of the samples are confirmed by X-ray powder diffraction (XRD) and Fourier-transform infrared spectroscopy (FTIR). The crystallite size of the samples is calculated by use of the Scherrer formula and is found to be within a range of 43-66 nm. The electrical conductivity of the samples is determined over a temperature range of 200-300 K by means of four-point probe method. An increasing trend of conductivity with increase in temperature is noted for all the samples. The parent compound LiMn 2O 4 has a conductivity value of 3.47 × 10 -4 ohm -1 cm -1 at room temperature. This value increases on doping with the above-mentioned transition metal cations.

  16. Synthesis and characterization of nanosized lithium manganate and its derivatives

    Energy Technology Data Exchange (ETDEWEB)

    Iqbal, Muhammad Javed; Zahoor, Sabia [Department of Chemistry, Quaid-i-Azam University, Islamabad 45320 (Pakistan)

    2007-02-25

    Spinel lithium manganese oxide, LiMn{sub 2}O{sub 4} and its derivatives are prepared by the sol-gel method. The lattice constant of the pure material is calculated as 8.23 Aa. Different transition metal cations of chromium, iron, cobalt, nickel, copper and zinc (0.05 and 0.15 M) are doped in place of manganese in the LiMn{sub 2}O{sub 4}. X-ray powder diffraction data show that the spinel framework preserved its integrity upon doping. Formation of a single phase and the purity of the samples are confirmed by X-ray powder diffraction (XRD) and Fourier-transform infrared spectroscopy (FTIR). The crystallite size of the samples is calculated by use of the Scherrer formula and is found to be within a range of 43-66 nm. The electrical conductivity of the samples is determined over a temperature range of 200-300 K by means of four-point probe method. An increasing trend of conductivity with increase in temperature is noted for all the samples. The parent compound LiMn{sub 2}O{sub 4} has a conductivity value of 3.47 x 10{sup -4} ohm{sup -1} cm{sup -1} at room temperature. This value increases on doping with the above-mentioned transition metal cations. (author)

  17. Synthesis and Bioactivity of Pyrazole Acyl Thiourea Derivatives

    Directory of Open Access Journals (Sweden)

    Jian Wu

    2012-05-01

    Full Text Available Sixteen novel pyrazole acyl thiourea derivatives 6 were synthesized from monomethylhydrazine (phenylhydrazine and ethyl acetoacetate. The key 5-chloro-3-methyl-1-substituted-1H-pyrazole-4-carbonyl chloride intermediates 4 were first generated in four steps through cyclization, formylation, oxidation and acylation. Thess were then reacted with ammonium thiocyanate in the presence of PEG-400 to afford 5-chloro-3-methyl-1-substituted-1H-pyrazole-4-carbonyl isothiocyanates 5. Subsequent reaction with fluorinated aromatic amines resulted in the formation of the title compounds. The synthesized compound were unequivocally characterized by IR, 1H-NMR, 13C-NMR and elemental analysis and some of the synthesized compounds displayed good antifungal activities against Gibberella zeae, Fusarium oxysporum, Cytospora mandshurica and anti-TMV activity in preliminary antifungal activity tests.

  18. Novel 2-Thioxanthine and Dipyrimidopyridine Derivatives: Synthesis and Antimicrobial Activity

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    Samar El-kalyoubi

    2015-10-01

    Full Text Available Several fused imidazolopyrimidines were synthesized starting from 6-amino-1-methyl-2-thiouracil (1 followed by nitrosation, reduction and condensation with different aromatic aldehydes to give Schiff’s base. The dehydrocyclization of Schiff’s bases using iodine/DMF gave Compounds 5a–g. The methylation of 5a–g using a simple alkylating agent as dimethyl sulfate ((CH32SO4 gave either monoalkylated imidazolopyrimidine 6a–g at room temperature or dialkylated derivatives 7a–g on heating 6a–g with ((CH32SO4. On the other hand, treatment of 1 with different aromatic aldehydes in absolute ethanol in the presence of conc. hydrochloric acid at room temperature and/or reflux with acetic acid afforded bis-5,5́-diuracylmethylene 8a–e, which cyclized on heating with a mixture of acetic acid/HCl (1:1 to give 9a–e. Compounds 9a–e can be obtained directly by refluxing of Compound 1 with a mixture of acetic acid/HCl. The synthesized new compounds were screened for antimicrobial activity, and the MIC was measured.

  19. Synthesis and Pharmacochemistry of New Pleiotropic Pyrrolyl Derivatives

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    Markella Konstantinidou

    2015-09-01

    Full Text Available Within the framework of our attempts to synthesize pleiotropic anti-inflammatory agents, we have synthesized some chalcones and their corresponding 3,4-pyrrolyl derivatives. Chalcones constitute a class of compounds with high biological impact. They are known for a number of biological activities, including anti-inflammatory and free radical scavenging activities. They inhibit several enzymes implicated in the inflammatory process, such as lipoxygenase, cyclooxygenase (COX and lysozymes. The synthesized pyrroles have been studied for: (1 their in vitro inhibition of lipoxygenase; (2 their in vitro inhibition of COX; (3 their in vitro inhibition of lipid peroxidation; (4 their interaction with the stable, N-centered, free radical, 2,2-diphenyl-1-picrylhydrazyl (DPPH; (5 their inhibition on interleukin-6 (IL-6; (6 their anti-proteolytic activity; and (7 their in vivo anti-inflammatory activity using carrageenan-induced rat paw edema. Their physicochemical properties were determined to explain the biological results. Lipophilicity was experimentally determined. 2i and 2v were found to be promising multifunctional molecules with high antiproteolytic and anti-inflammatory activities in combination with anti-interleukin-6 activity.

  20. Synthesis of 2-phenylamino-thiazole derivatives as antimicrobial agents

    Directory of Open Access Journals (Sweden)

    Dominique Serge Ngono Bikobo

    2017-11-01

    Full Text Available A series of 10 new N-phenyl-4-(4-(thiazol-2-yl-phenyl-thiazol-2-amine derivatives (3a–j and 4 new 5-(2-(phenylamino-thiazol-4-yl-benzamide ethers (3′a–d were synthesized from 4-(2-phenylamino-thiazol-4-yl-benzothioamide and 2-hydroxy-5-(2-(phenylamino-thiazol-4-yl-benzamide with several α-halo-ketones, by the Hantzsch reaction. All compounds were characterized by elemental analysis and spectral data (MS, FT-IR and NMR. The final 14 substances were screened for antimicrobial activity, against two Gram-positive, one Gram-negative bacterial strains, and two fungal strains. Some of the synthesized molecules were more potent than the reference drugs, against the pathogenic strains used. The antibacterial activity of compounds was more pronounced against the Gram-positive strains. Compound 3e manifested the highest growth inhibitory effect against all pathogens tested (MIC of 31.25 μg/mL against the Gram-positive bacterial strains and 7.81 μg/mL against the Candida strains.

  1. Reaction scheme of partial oxidation of methane to synthesis gas over yttrium-stabilized zirconia

    NARCIS (Netherlands)

    Zhu, J.J.; van Ommen, J.G.; Lefferts, Leonardus

    2004-01-01

    The partial oxidation of methane to synthesis gas over yttrium-stabilized zirconia (YSZ) was studied with in situ FTIR and both steady-state and transient experiments. The four major products, CO, H2, CO2, and H2O, are primary products of CPOM over YSZ. Besides these major products and traces of

  2. Alternate fuels and chemicals from synthesis gas: Vinyl acetate monomer. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Richard D. Colberg; Nick A. Collins; Edwin F. Holcombe; Gerald C. Tustin; Joseph R. Zoeller

    1999-01-01

    There has been a long-standing desire on the part of industry and the U.S. Department of Energy to replace the existing ethylene-based vinyl acetate monomer (VAM) process with an entirely synthesis gas-based process. Although there are a large number of process options for the conversion of synthesis gas to VAM, Eastman Chemical Company undertook an analytical approach, based on known chemical and economic principles, to reduce the potential candidate processes to a select group of eight processes. The critical technologies that would be required for these routes were: (1) the esterification of acetaldehyde (AcH) with ketene to generate VAM, (2) the hydrogenation of ketene to acetaldehyde, (3) the hydrogenation of acetic acid to acetaldehyde, and (4) the reductive carbonylation of methanol to acetaldehyde. This report describes the selection process for the candidate processes, the successful development of the key technologies, and the economic assessments for the preferred routes. In addition, improvements in the conversion of acetic anhydride and acetaldehyde to VAM are discussed. The conclusion from this study is that, with the technology developed in this study, VAM may be produced from synthesis gas, but the cost of production is about 15% higher than the conventional oxidative acetoxylation of ethylene, primarily due to higher capital associated with the synthesis gas-based processes.

  3. Methanol synthesis in a countercurrent gas-solid-solid trickle flow reactor. An experimental study

    NARCIS (Netherlands)

    Kuczynski, M.; Oyevaar, M.H.; Pieters, R.T.; Westerterp, K.R.

    1987-01-01

    The synthesis of methanol from CO and H2 was executed in a gas-solid-solid trickle flow reactor. The reactor consisted of three tubular reactor sections with cooling sections in between. The catalyst was Cu on alumina, the adsorbent was a silica-alumina powder and the experimental range 498–523 K,

  4. Preliminary assessment of synthesis gas production via hybrid steam reforming of methane and glycerol

    NARCIS (Netherlands)

    Balegedde Ramachandran, P.; van Rossum, G.; Kersten, Sascha R.A.; van Swaaij, Willibrordus Petrus Maria

    2012-01-01

    In this article, hybrid steam reforming (HSR) of desulphurized methane, together with crude glycerol, in existing commercial steam reformers to produce synthesis gas is proposed. The proposed concept consists of a gasifier to produce vapors, gases, and char from crude glycerol, which is coupled with

  5. Environmental Transmission Electron Microscopy (ETEM) Studies of Single Iron Nanoparticle Carburization in Synthesis Gas

    DEFF Research Database (Denmark)

    Liu, Xi; Zhang, Chenghua; Li, Yongwang

    2017-01-01

    Structuralevolution of iron nanoparticles involving the formationand growth of iron carbide nuclei in the iron nanoparticle was directlyvisualized at the atomic level, using environmental transmission electronmicroscopy (TEM) under reactive conditions mimicking Fischer–Tropschsynthesis. Formation...... and electronenergy-loss spectra provides a detailed picture from initial activationto final degradation of iron under synthesis gas....

  6. Synthesis, characterization and gas sensing performance of SnO2 ...

    Indian Academy of Sciences (India)

    Synthesis, characterization and gas sensing performance of SnO2 thin films prepared by spray pyrolysis. GANESH E PATIL, D D KAJALE, D N CHAVAN†, N K PAWAR††, P T AHIRE, S D SHINDE#,. V B GAIKWAD# and G H JAIN. ∗. Materials Research Laboratory, Arts, Commerce and Science College, Nandgaon 423 106, ...

  7. Controlled synthesis of the tricontinuous mesoporous material IBN-9 and its carbon and platinum derivatives

    KAUST Repository

    Zhao, Yunfeng

    2011-08-23

    Controlled synthesis of mesoporous materials with ultracomplicated pore configurations is of great importance for both fundamental research of nanostructures and the development of novel applications. IBN-9, which is the only tricontinuous mesoporous silica with three sets of interpenetrating three-dimensional channel systems, appears to be an excellent model mesophase for such study. The extensive study of synthesis space diagrams proves mesophase transition among the cylindrical MCM-41, tricontinuous IBN-9 and bicontinuous MCM-48, and also allows a more precise control of phase-pure synthesis. On the other hand, rational design of structure-directing agents offers a possibility to extend the synthesis conditions of IBN-9, as well as tailor its pore size. Moreover, an unprecedented helical structure consisting of twisted 3-fold interwoven mesoporous channels is reported here for the first time. The unique tricontinuous mesostructure of IBN-9 has been well-replicated by other functional materials (e.g., carbon and platinum) via a "hard- templating" synthesis route. The obtained carbon material possesses large surface area (∼1900 m2/g), high pore volume (1.56 cm 3/g), and remarkable gas adsorption capability at both cryogenic temperatures and room temperature. The platinum material has an ordered mesostructure composed of highly oriented nanocrystals. © 2011 American Chemical Society.

  8. Lanthanide nitrates as Lewis acids in the one-pot synthesis of 1,2,4-oxadiazole derivatives

    Energy Technology Data Exchange (ETDEWEB)

    Vale, Juliana A.; Faustino, Wagner M., E-mail: julianadqf@yahoo.com.br [Departamento de Quimica, Universidade Federal da Paraiba, Joao Pessoa, PB (Brazil); Zampieri, Davila de S.; Moran, Paulo J.S.; Rodrigues, Jose A.R. [Instituto de Quimica, Universidade Estadual de Campinas, SP (Brazil); Sa, Gilberto F. de [Departamento de Quimica Fundamental, CCEN, Universidade Federal de Pernambuco, Recife, PE (Brazil)

    2012-08-15

    In this work we report the use of lanthanide nitrates [Ln(NO{sub 3}){sub 3}] acting as catalyst in direct one pot synthesis of 3-benzoyl- and 3-acetyl-1,2,4-oxadiazoles derivatives from ketones, nitriles and nitric acid. This is the first example of one-pot synthesis of benzoyl- and acetyl 1,2,4-oxadiazoles derivatives preparation using acetophenones derivates with electron-donator groups. (author)

  9. Some new techniques in tritium gas handling as applied to metal hydride synthesis

    International Nuclear Information System (INIS)

    Nasise, J.E.

    1988-01-01

    A state-of-the-art tritium Hydriding Synthesis System (HSS) was designed and built to replace the existing system within the Tritium Salt Facility (TSF) at the Los Alamos National Laboratory. This new hydriding system utilizes unique fast-cycling 7.9 mole uranium beds (47.5g of T at 100% loading) and novel gas circulating hydriding furnaces. Tritium system components discussed include fast-cycling uranium beds, circulating gas hydriding furnaces, valves, storage volumes, manifolds, gas transfer pumps, and graphic display and control consoles. Many of the tritium handling and processing techniques incorporated into this system are directly applicable to today's fusion fuel loops. 12 refs., 7 figs

  10. Ultrasonic experiment on hydrate formation of a synthesis gas

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Shicai; Fan, Shuanshi; Liang, Deqing; Zhang, Junshe; Feng, Ziping

    2005-07-01

    The effect of ultrasonic on the induction time and formation rate of natural gas hydrates was investigated in a stainless steel cell in this study. The results show that the induction time with ultrasonic was about 1/6 of that without ultrasonic and only about 1/10 if rehydration after decomposition in water-gas system. In sodium dodecyl sulfate (SDS) solution-gas system, the critical micellar concentration (CMC) was not identified with ultrasonic. The formation rate and storage capacity of hydrate increased with increasing SDS concentration at a range of 0 to 800ppm. However, the increase was insignificant as the SDS concentration increased from 600 to 800ppm, (Author)

  11. New Fokker-Planck derivation of heavy gas models for neutron thermalization

    International Nuclear Information System (INIS)

    Larsen, E.W.; Williams, M.M.R.

    1990-01-01

    This paper is concerned with the derivation of new generalized heavy gas models for the infinite medium neutron energy spectrum equation. Our approach is general and can be used to derive improved Fokker-Planck approximations for other types of kinetic equations. In this paper we obtain two distinct heavy gas models, together with estimates for the corresponding errors. The models are shown in a special case to reduce to modified heavy gas models proposed earlier by Corngold (1962). The error estimates show that both of the new models should be more accurate than Corngold's modified heavy gas model, and that the first of the two new models should generally be more accurate than the second. (author)

  12. Chemical equilibrium. [maximizing entropy of gas system to derive relations between thermodynamic variables

    Science.gov (United States)

    1976-01-01

    The entropy of a gas system with the number of particles subject to external control is maximized to derive relations between the thermodynamic variables that obtain at equilibrium. These relations are described in terms of the chemical potential, defined as equivalent partial derivatives of entropy, energy, enthalpy, free energy, or free enthalpy. At equilibrium, the change in total chemical potential must vanish. This fact is used to derive the equilibrium constants for chemical reactions in terms of the partition functions of the species involved in the reaction. Thus the equilibrium constants can be determined accurately, just as other thermodynamic properties, from a knowledge of the energy levels and degeneracies for the gas species involved. These equilibrium constants permit one to calculate the equilibrium concentrations or partial pressures of chemically reacting species that occur in gas mixtures at any given condition of pressure and temperature or volume and temperature.

  13. Clean and Green Synthesis of New Benzothiazole Derivatives via Electrochemical Oxidation of Catechol Derivatives

    Directory of Open Access Journals (Sweden)

    Mansour Arab Chamjangali

    2016-06-01

    Full Text Available Electrochemical oxidation of the catechols 1a and 1b is studied in the presence of 6-methyl-2-thouracil (3b and 6-propyl-2-thiouracil (3a as nucleophiles in a phosphate buffer (0.15 mol L−1, pH = 6.8/DMF (95:5 solution using cyclic voltammetry and controlled-potential coulometry. The results obtained indicate that the quinones derived from the catechols participate in 1,4-Michael-addition reactions with the nucleophiles to form the corresponding new benzothiazole compounds. In this work, we derive a variety of products with good yields using controlled potential at graphite electrodes in an undivided cell. This work is licensed under a Creative Commons Attribution 4.0 International License.

  14. Second derivative Langmuir probe diagnostics of gas discharge plasma at intermediate pressures (review article)

    International Nuclear Information System (INIS)

    Popov, Tsv K; Dimitrova, M; Dias, F M; Tsaneva, V N; Stelmashenko, N A; Blamire, M G; Barber, Z H

    2006-01-01

    The second-derivative Langmuir probe method for precise determination of the plasma potential, the electron energy distribution function (respectively the electron temperature,) and the electron density of gas discharge plasma at intermediate pressures (100-1000 Pa) is reviewed. Results of applying the procedure proposed to different kinds of gas discharges are presented. Factors affecting the accuracy of the plasma characteristics evaluated are discussed

  15. Copper-catalyzed aerobic oxidative C-H functionalization of substituted pyridines: synthesis of imidazopyridine derivatives.

    Science.gov (United States)

    Yu, Jipan; Jin, Yunhe; Zhang, Hao; Yang, Xiaobo; Fu, Hua

    2013-12-02

    A novel, efficient, and practical method for the synthesis of imidazopyridine derivatives has been developed through the copper-catalyzed aerobic oxidative C-H functionalization of substituted pyridines with N-(alkylidene)-4H-1,2,4-triazol-4-amines. The procedure occurs by cleavage of the N-N bond in the N-(alkylidene)-4H-1,2,4-triazol-4-amines and activation of an aryl C-H bond in the substituted pyridines. This is the first example of the preparation of imidazopyridine derivatives by using pyridines as the substrates by transition-metal-catalyzed C-H functionalization. This method should provide a novel and efficient strategy for the synthesis of other nitrogen heterocycles. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Magnetic nanoparticle supported phosphotungstic acid: An efficient catalyst for the synthesis of xanthene derivatives

    Science.gov (United States)

    Patel, Nipun; Katheriya, Deepak; Dadhania, Harsh; Dadhania, Abhishek

    2018-05-01

    Magnetic nanoparticle supported phosphotungstic acid (Fe3O4@SiO2-HPW) was applied as a highly efficient catalyst for the synthesis of 14H-dibenzoxanthene derivatives via condensation reaction of 2-naphthol and aryl aldehydes. The catalyst was found highly efficient for the synthesis of xanthene derivatives under solvent free condition. The catalyst showed high activity and stability during the reaction and provided excellent yield of the corresponding products in short reaction time. All the synthesized compounds were characterized through FT-IR, 1H-NMR and 13C-NMR spectroscopic techniques. Furthermore, the catalyst is magnetically recoverable and can be reused several times without significant loss of its catalytic activity.

  17. Discovery of Antibiotics-derived Polymers for Gene Delivery using Combinatorial Synthesis and Cheminformatics Modeling

    Science.gov (United States)

    Potta, Thrimoorthy; Zhen, Zhuo; Grandhi, Taraka Sai Pavan; Christensen, Matthew D.; Ramos, James; Breneman, Curt M.; Rege, Kaushal

    2014-01-01

    We describe the combinatorial synthesis and cheminformatics modeling of aminoglycoside antibiotics-derived polymers for transgene delivery and expression. Fifty-six polymers were synthesized by polymerizing aminoglycosides with diglycidyl ether cross-linkers. Parallel screening resulted in identification of several lead polymers that resulted in high transgene expression levels in cells. The role of polymer physicochemical properties in determining efficacy of transgene expression was investigated using Quantitative Structure-Activity Relationship (QSAR) cheminformatics models based on Support Vector Regression (SVR) and ‘building block’ polymer structures. The QSAR model exhibited high predictive ability, and investigation of descriptors in the model, using molecular visualization and correlation plots, indicated that physicochemical attributes related to both, aminoglycosides and diglycidyl ethers facilitated transgene expression. This work synergistically combines combinatorial synthesis and parallel screening with cheminformatics-based QSAR models for discovery and physicochemical elucidation of effective antibiotics-derived polymers for transgene delivery in medicine and biotechnology. PMID:24331709

  18. Energy and greenhouse gas profiles of polyhydroxybutyrates derived from corn grain: a life cycle perspective.

    Science.gov (United States)

    Kim, Seungdo; Dale, Bruce E

    2008-10-15

    Polyhydroxybutyrates (PHB) are well-known biopolymers derived from sugars orvegetable oils. Cradle-to-gate environmental performance of PHB derived from corn grain is evaluated through life cycle assessment (LCA), particularly nonrenewable energy consumption and greenhouse gas emissions. Site-specific process information on the corn wet milling and PHB fermentation and recovery processes was obtained from Telles. Most of energy used in the corn wet milling and PHB fermentation and recovery processes is generated in a cogeneration power plant in which corn stover, assumed to be representative of a variety of biomass sources that could be used, is burned to generate electricity and steam. County level agricultural information is used in estimating the environmental burdens associated with both corn grain and corn stover production. Results show that PHB derived from corn grain offers environmental advantages over petroleum-derived polymers in terms of nonrenewable energy consumption and greenhouse gas emissions. Furthermore, PHB provides greenhouse gas credits, and thus PHB use reduces greenhouse gas emissions compared to petroleum-derived polymers. Corn cultivation is one of the environmentally sensitive areas in the PHB production system. More sustainable practices in corn cultivation (e.g., using no-tillage and winter cover crops) could reduce the environmental impacts of PHB by up to 72%.

  19. Solvent-Free Synthesis of Quaternary Metal Sulfide Nanoparticles Derived from Thiourea

    KAUST Repository

    Bhunia, Manas Kumar

    2017-08-09

    The synthesis of metal sulfide (MS) materials with sizes in the sub-10 nm regime often requires capping agents with long hydrocarbon chains that affect their structures and properties. Herein, this study presents a molten-state synthesis method for a series of transition-MS nanoparticles using thiourea as a reactive precursor without capping agents. This study also reports the synthesis of MS with single metals (Fe, Co, Ni, Cu, and Zn) and quaternary CuGa2In3S8 using the same synthesis protocol. Thiourea first melts to form a molten-state condition to serve as the reaction medium at a relatively low temperature (<200 °C), followed by its thermal decomposition to induce a reaction with the metal precursor to form different MS. This synthesis protocol, owing to its dynamic characteristics, involves the formation of a variety of organic carbon nitride polymeric complexes around the MS particles. Dynamic nuclear polarization surface-enhanced nuclear magnetic resonance spectroscopy is effective to identify the polymeric compositions and structures as well as their interactions with the MS. These results provided thorough structural descriptions of the MS nanoparticles surrounded by the carbon nitride species derived from thiourea, which may find various applications, including photocatalytic water splitting.

  20. Synthesis of the derivatives of 6-amino-uracil labelled with C-14

    Czech Academy of Sciences Publication Activity Database

    Elbert, Tomáš; Hezký, Petr; Jansa, Petr

    2016-01-01

    Roč. 59, č. 14 (2016), s. 615-618 ISSN 0362-4803. [International Isotope Symposium on the Synthesis and Applications of Isotopes and Isotopically Labelled Compounds /12./. Princeton, 07.06.2015-11.06.2015] R&D Projects: GA MŠk LG13002 Institutional support: RVO:61388963 Keywords : 6-amino-uracil derivatives * specific activity assay using NMR * [C-14]cyanoacetic acid Subject RIV: CC - Organic Chemistry Impact factor: 1.745, year: 2016

  1. Synthesis of novel kavain-like derivatives and evaluation of their cytotoxic activity

    Energy Technology Data Exchange (ETDEWEB)

    Amaral, Patricia de A.; Agustini, Taciane; Eifler-Lima, Vera L. [Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre (Brazil). Faculdade de Farmacia. Lab. de Sintese Organica Medicinal; Petrignet, Julien; Cariou, Alexandre; Gree, Rene [Universite de Rennes 1, Rennes (France). Lab. de Chimie Therapeutique; Gouault, Nicolas; Lohezic-Ledevehat, Francoise; David, Michele [CNRS UMR, Universite de Rennes 1, Rennes (France). Lab. de Chimie et Photonique Moleculaires

    2009-07-01

    Palladium-catalyzed cross coupling reactions (Sonogashira-Hagihara, Suzuki-Miyaura, and Heck) coupling and nickel hydride-mediated tandem isomerization aldolisation have been used for the synthesis of three series of {delta}-valerolactones substituted in positions 3, 4, 5 and 6 of the lactone ring. The 26 kavaien-like derivatives were tested against three cell lines and five of them exhibited a weak cytotoxic activity. (author)

  2. Easy Access to Evans’ Oxazolidinones. Stereoselective Synthesis and Antibacterial Activity of a New 2-Oxazolidinone Derivative

    Directory of Open Access Journals (Sweden)

    Gaspar Diaz

    2014-06-01

    Full Text Available An interesting new approach was developed for the synthesis of Evans’ chiral auxiliaries with excellent yields. In turn, another new stereoselective and efficient strategy has also allowed for the preparation of a 2-oxazolidinone derivative in 34% overall yield from the Morita-Baylis-Hillman adduct. The antibacterial activity of this oxazolidinone was tested against Staphylococcus aureus strains isolated from animals with mastitis infections.

  3. Effect of structural promoters on Fe-based Fischer-Tropsch synthesis of biomass derived syngas

    Science.gov (United States)

    Pratibha Sharma; Thomas Elder; Leslie H. Groom; James J. Spivey

    2014-01-01

    Biomass gasification and subsequent conversion of this syngas to liquid hydrocarbons using Fischer–Tropsch (F–T) synthesis is a promising source of hydrocarbon fuels. However, biomass-derived syngas is different from syngas obtained from other sources such as steam reforming of methane. Specifically the H2/CO ratio is less than 1/1 and the CO

  4. Spin labeled amino acid nitrosourea derivatives--synthesis and antitumour activity.

    Science.gov (United States)

    Zheleva, A; Raikov, Z; Ilarionova, M; Todorov, D

    1995-01-01

    The synthesis of three spin labeled derivatives of N-[N'-(chloroethyl)-N'-nitrosocarbamoyl] amino acids is reported. The new nitrosoureas are obtained by condensation of the corresponding N-[N'-(2-chloroethyl)-N'-nitrosocarbamoyl] amino acid with 2,2,6,6-tetramethyl-1-oxyl-4-aminopiperidine using dicyclohexylcarbodiimide. Their chemical structures are confirmed by elemental analysis, IR, MS, and EPR spectroscopy. All newly synthesized compounds showed high antitumour activity against the lymphoid leukemia L1210 in BDF1 mice.

  5. Synthesis of D-fructose-derived spirocyclic 2-substituted-2-oxazoline ribosides

    Directory of Open Access Journals (Sweden)

    Madhuri Vangala

    2015-11-01

    Full Text Available The TMSOTf-mediated synthesis of β-configured spirocyclic 2-substituted-2-oxazoline ribosides was achieved using a “Ritter-like” reaction in toluene through nucleophilic addition of electron-rich nitriles to the oxacarbenium ion intermediate of 1,2;3,4-di-O-isopropylidene-β-D-psicofuranose derivatives with concomitant intramolecular trapping of the C2 hydroxymethyl group on the electrophilic nitrilium carbon. These carbohydrate-derived spirooxazolines are stable and were obtained in good yield with high stereoselectivity due to the conformational rigidity imparted by the 3,4-isopropylidene group.

  6. Multifaceted Strategy for the Synthesis of Diverse 2,2'-Bithiophene Derivatives

    Directory of Open Access Journals (Sweden)

    Stanisław Krompiec

    2015-03-01

    Full Text Available New catalytically or high pressure activated reactions and routes, including coupling, double bond migration in allylic systems, and various types of cycloaddition and dihydroamination have been used for the synthesis of novel bithiophene derivatives. Thanks to the abovementioned reactions and routes combined with non-catalytic ones, new acetylene, butadiyne, isoxazole, 1,2,3-triazole, pyrrole, benzene, and fluoranthene derivatives with one, two or six bithiophenyl moieties have been obtained. Basic sources of crucial substrates which include bithiophene motif for catalytic reactions were 2,2'-bithiophene, gaseous acetylene and 1,3-butadiyne.

  7. Synthesis and antimycobacterial activity of isoniazid derivatives from renewable fatty acids.

    Science.gov (United States)

    Rodrigues, Marieli O; Cantos, Jéssica B; D'Oca, Caroline R Montes; Soares, Karina L; Coelho, Tatiane S; Piovesan, Luciana A; Russowsky, Dennis; da Silva, Pedro A; D'Oca, Marcelo G Montes

    2013-11-15

    This work describes the synthesis of a series of fatty acid hydrazide derivatives of isoniazid (INH). The compounds were tested against Mycobacterium tuberculosis H37Rv (ATCC 27294) as well as INH-resistant (ATCC 35822 and 1896 HF) and rifampicin-resistant (ATCC 35338) M. tuberculosis strains. The fatty acid derivatives of INH showed high antimycobacterial potency against the studied strains, which is desirable for a pharmaceutical compound, suggesting that the increased lipophilicity of isoniazid plays an important role in its antimycobacterial activity. Copyright © 2013 Elsevier Ltd. All rights reserved.

  8. Synthesis of biotinyl derivatives of peptide hormones and other biological materials

    International Nuclear Information System (INIS)

    Finn, F.M.; Hofmann, K.H.

    1985-01-01

    Methods for the preparation of biotinylated ligands for the avidin-biotin system are described. Also described are procedures for modifying and labelling avidin and for assessing the rate of dissociation of biotin derivatives from avidin. The most widely used procedure for introducing biotin into other molecules involves acylation with N-hydroxysuccinimido-biotinate. Experimental details are given for the synthesis of dethiobiotin, iminobiotin, and biotinylated ligands in which a 6-aminohexanoic acid spacer is interposed between the biotin or biotin derivative and the insulin molecule. The syntheses of biotinylated corticotropins are presented only in principle

  9. Polycyclic Aromatic Compounds as Anticancer Agents: Synthesis and Biological Evaluation of Methoxy Dibenzofluorene Derivatives

    Directory of Open Access Journals (Sweden)

    Bimal Krishna Banik

    2014-08-01

    Full Text Available Synthesis of a new methoxy dibenzofluorene through alkylation, cyclodehydration and aromatization in a one-pot operation is achieved for the first time. Using this hydrocarbon, a few derivatives are prepared through aromatic nitration, catalytic hydrogenation, coupling reaction with a side chain and reduction. The benzylic position of this hydrocarbon with the side chain is oxidized and reduced. Some of these derivatives have demonstrated excellent antitumor activities in vitro. This study confirms antitumor activity depends on the structures of the molecules.

  10. Development and optimization of the synthesis of new thiazolidin-4-one derivatives of ibuprofen.

    Science.gov (United States)

    Vasincu, Ioana; Apotrosoaei, Maria; Panzariu, Andreea; Buron, F; Routier, S; Profire, Lenuta

    2014-01-01

    Ibuprofen, an important nonsteroidal anti-inflammatory agent, is one of the most prescribed drugs for the treatment of pain and inflammation from various rheumatic diseases, but some side effects can occur on long-term use. The method for synthesis optimization of new derivatives of Ibuprofen with thiazolidin-4-one moiety, with improved pharmacological and toxicological profile. To optimize the derivatization method of free carboxyl group of Ibuprofen (2-(4-isobutylphenyl)propionic acid) the reaction conditions were varied (reagent ratio, catalyst, reaction medium). The most favorable method was proved to be the reaction between ibuprofen hydrazone and mercaptoacetic acid, in excess, at 80-85 degrees C, for 6 h with 96% conversion rate. The synthesis of 2-phenyl-3-[2-(4-(isobutyl)phenyl)-2-methyl]acetamido-thiazolidin-4-one derivative was optimized in view of applying it as a general procedure for the synthesis of other derivatives with related structure. The chemical structure and molecular weight of the synthesized compound were confirmed by spectral methods (IR, 1H NMR, 13C NMR, HR-MS).

  11. Synthesis, Characterization, and Gas Sensing Applications of WO3 Nanobricks

    Science.gov (United States)

    Xiao, Jingkun; Song, Chengwen; Dong, Wei; Li, Chen; Yin, Yanyan; Zhang, Xiaoni; Song, Mingyan

    2015-08-01

    WO3 nanobricks are fabricated by a simple hydrothermal method. Morphology and structure of the WO3 nanobricks are characterized by scanning electron microscopy and x-ray diffraction. Gas sensing properties of the as-prepared WO3 sensor are systematically investigated by a static gas sensing system. The results show that the WO3 nanobricks with defect corners demonstrate good crystallinity, and the mean edge length and wall thickness are 1-1.5 and 400 nm, respectively. The WO3 sensor achieves its maximum sensitivity to 100 ppm ethanol at the optimal operating temperature of 300 °C. Ultra-fast response time (2-3 s) and fast recovery time (4-11 s) of the WO3 sensor toward 100 ppm ethanol are also observed at this optimal operating temperature. Moreover, the WO3 sensor exhibits high selectivity to other gases such as methanol, benzene, hexane, and dichloromethane, indicating its excellent potential application as a gas sensor for ethanol detection.

  12. Synthesis of novel (-)-epicatechin derivatives as potential endothelial GPER agonists: Evaluation of biological effects.

    Science.gov (United States)

    Sarmiento, Viviana; Ramirez-Sanchez, Israel; Moreno-Ulloa, Aldo; Romero-Perez, Diego; Chávez, Daniel; Ortiz, Miguel; Najera, Nayelli; Correa-Basurto, Jose; Villarreal, Francisco; Ceballos, Guillermo

    2018-02-15

    To potentially identify proteins that interact (i.e. bind) and may contribute to mediate (-)-epicatechin (Epi) responses in endothelial cells we implemented the following strategy: 1) synthesis of novel Epi derivatives amenable to affinity column use, 2) in silico molecular docking studies of the novel derivatives on G protein-coupled estrogen receptor (GPER), 3) biological assessment of the derivatives on NO production, 4) implementation of an immobilized Epi derivative affinity column and, 5) affinity column based isolation of Epi interacting proteins from endothelial cell protein extracts. For these purposes, the Epi phenol and C3 hydroxyl groups were chemically modified with propargyl or mesyl groups. Docking studies of the novel Epi derivatives on GPER conformers at 14 ns and 70 ns demostrated favorable thermodynamic interactions reaching the binding site. Cultures of bovine coronary artery endothelial cells (BCAEC) treated with Epi derivatives stimulated NO production via Ser1179 phosphorylation of eNOS, effects that were attenuated by the use of the GPER blocker, G15. Epi derivative affinity columns yielded multiple proteins from BCAEC. Proteins were electrophoretically separated and inmmunoblotting analysis revealed GPER as an Epi derivative binding protein. Altogether, these results validate the proposed strategy to potentially isolate and identify novel Epi receptors that may account for its biological activity. Copyright © 2018 Elsevier Ltd. All rights reserved.

  13. A review of recent advances in molecular simulation of graphene-derived membranes for gas separation

    Science.gov (United States)

    Fatemi, Seyyed Mahmood; Abbasi, Zeynab; Rajabzadeh, Halimeh; Hashemizadeh, Seyyed Ali; Deldar, Amir Noori

    2017-07-01

    To obtain an ideal membrane for gas separation the following three characteristics should be considered: the membrane should be as thin as possible, be mechanically robust, and have well-defined pore sizes. These features will maximize its solvent flux, preserve it from fracture, and guarantee its selectivity. These attractive properties of graphene-derived membranes introduce them as appropriate candidates for gas separation and gas molecular-sieving processes in nanoscale dimensions. The current effort has focused on two issues, including the review of the most newly progression on drilling holes in single graphene membranes for making ultrathin membranes for gas separation, and studying functionalized nanoporous sheet and graphene-derived membranes, including doped graphene, graphene oxide, fluorographene, and reduced graphene oxide from theoretical perspectives for making functional coatings for nano ultrafiltration for gas separation. We investigated the basic mechanism of separation by membranes derived from graphene and relevant possible applications. Functionalized nanoporous membranes as novel approach are characterized by low energy cost in realizing high throughput molecular-sieving separation.

  14. Tar removal from biomass derived fuel gas by pulsed corona discharges: chemical kinetic study II

    NARCIS (Netherlands)

    Nair, S.A.; Yan, K.; Pemen, A.J.M.; Heesch, van E.J.M.; Ptasinski, K.J.; Drinkenburg, A.A.H.

    2005-01-01

    Tar (heavy hydrocarbon or poly aromatic hydrocarbon (PAH)) removal from biomass derived fuel gas is one of the biggest obstacles in its utilization for power generation. We have investigated pulsed corona as a method for tar removal. Our previous experimental results indicate the energy consumption

  15. Synthesis of pyrido[1,2-a]benzimidazoles and other fused imidazole derivatives with a bridgehead nitrogen atom

    Science.gov (United States)

    Begunov, Roman S.; Ryzvanovich, Galina A.

    2013-01-01

    Main methods for the synthesis of fused imidazole derivatives with a bridgehead nitrogen atom are systematically considered and summarized. The reaction mechanisms that underlie the methods for the synthesis of pyrido[1,2-a]benzimidazoles and related compounds are described. Biological properties and mechanisms of the biological activity of fused azaheterocycles are discussed. The bibliography includes 152 references.

  16. Facile nanofibrillation of chitin derivatives by gas bubbling and ultrasonic treatments in water.

    Science.gov (United States)

    Tanaka, Kohei; Yamamoto, Kazuya; Kadokawa, Jun-ichi

    2014-10-29

    In this paper, we report that nanofiber network structures were constructed from chitin derivatives by gas bubbling and ultrasonic treatments in water. When chitin was first subjected to N2 gas bubbling with ultrasonication in water, the SEM images of the product showed nanofiber network morphology. However, nanofiber network was not re-constructed by the same N2 gas bubbling and ultrasonic treatments after agglomeration. We then have paid attention to an amidine group to provide the agglomeration-nanofibrillation behavior of chitin derivatives. An amidinated chitin was synthesized by the reaction of the amino groups in a partially deacetylated chitin with N,N-dimethylacetamide dimethyl acetal, which was subjected to CO2 gas bubbling and ultrasonic treatments in water to convert into an amidinium chitin by protonation. The SEM images of the product clearly showed nanofiber network morphology. We further examined re-nanofibrillation of the agglomerated material, which was obtained by mixing the nanofibrillated amidinium chitin with water, followed by drying under reduced pressure. Consequently, the material was re-nanofibrillated by N2 gas bubbling with ultrasonication in water owing to electrostatic repulsion between the amidinium groups. Furthermore, deprotonation of the amidinium chitin and re-protonation of the resulting amidinated chitin were conducted by alkaline treatment and CO2 gas bubbling-ultrasonic treatments, respectively. The material showed the agglomeration-nanofibrillation behavior during the processes. Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. Synthesis of N-methyl-N-formyltyramine, a new {beta}-phenethylamide derivative isolated from Cyathobasis fruticulosa (Bunge) aellen

    Energy Technology Data Exchange (ETDEWEB)

    Larghi, Enrique L.; Kaufman, Teodoro S. [Universidad Nacional de Rosario, Rosario (Argentina). Instituto de Quimica Organica de Sintesis (IQUIOS); Universidad Nacional de Rosario, Rosario (Argentina). Facultad de Ciencias Bioquimicas y Farmaceuticas; E-mail: tkaufman@fbioyf.unr.edu.ar

    2006-05-15

    The synthesis of N-methyl-N-formyltyramine, a novel {beta}-phenethylamide derivative isolated from Cyathobasis fructiculosa (Bunge) Aellen, is reported. The natural product was prepared in six steps and good overall yield from 4-hydroxybenzaldehyde. (author)

  18. Correction: Synthesis of pyrrolidine-3-carboxylic acid derivatives via asymmetric Michael addition reactions of carboxylate-substituted enones.

    Science.gov (United States)

    Yin, Feng; Garifullina, Ainash; Tanaka, Fujie

    2018-04-25

    Correction for 'Synthesis of pyrrolidine-3-carboxylic acid derivatives via asymmetric Michael addition reactions of carboxylate-substituted enones' by Feng Yin et al., Org. Biomol. Chem., 2017, 15, 6089-6092.

  19. Atmospheric-pressure dielectric barrier discharge with capillary injection for gas-phase nanoparticle synthesis

    International Nuclear Information System (INIS)

    Ghosh, Souvik; Liu, Tianqi; Bilici, Mihai; Cole, Jonathan; Huang, I-Min; Sankaran, R Mohan; Staack, David; Mariotti, Davide

    2015-01-01

    We present an atmospheric-pressure dielectric barrier discharge (DBD) reactor for gas-phase nanoparticle synthesis. Nickel nanoparticles are synthesized by homogenous nucleation from nickelocene vapor and characterized online by aerosol mobility measurements. The effects of residence time and precursor concentration on particle growth are studied. We find that narrower distributions of smaller particles are produced by decreasing the precursor concentration, in agreement with vapor nucleation theory, but larger particles and aggregates form at higher gas flow rates where the mean residence time should be reduced, suggesting a cooling effect that leads to enhanced particle nucleation. In comparison, incorporating a capillary gas injector to alter the velocity profile is found to significantly reduce particle size and agglomeration. These results suggest that capillary gas injection is a better approach to decreasing the mean residence time and narrowing the residence time distribution for nanoparticle growth by producing a sharp and narrow velocity profile. (paper)

  20. SnO2 Nanostructure as Pollutant Gas Sensors: Synthesis, Sensing Performances, and Mechanism

    Directory of Open Access Journals (Sweden)

    Brian Yuliarto

    2015-01-01

    Full Text Available A significant amount of pollutants is produced from factories and motor vehicles in the form of gas. Their negative impact on the environment is well known; therefore detection with effective gas sensors is important as part of pollution prevention efforts. Gas sensors use a metal oxide semiconductor, specifically SnO2 nanostructures. This semiconductor is interesting and worthy of further investigation because of its many uses, for example, as lithium battery electrode, energy storage, catalyst, and transistor, and has potential as a gas sensor. In addition, there has to be a discussion of the use of SnO2 as a pollutant gas sensor especially for waste products such as CO, CO2, SO2, and NOx. In this paper, the development of the fabrication of SnO2 nanostructures synthesis will be described as it relates to the performances as pollutant gas sensors. In addition, the functionalization of SnO2 as a gas sensor is extensively discussed with respect to the theory of gas adsorption, the surface features of SnO2, the band gap theory, and electron transfer.

  1. Boron-containing catalysts for dry reforming of methane to synthesis gas

    KAUST Repository

    Takanabe, Kazuhiro

    2018-01-04

    The present invention uses a cobalt catalyst for carbon dioxide reforming of lower alkanes to synthesis gas having a cobalt catalyst on an oxide support where the supported cobalt catalyst has been modified with a boron precursor. The boron-treated cobalt catalyst systems as described herein show significant increases in the conversion of CH4 and CO2 during the dry reforming of methane (DRM) reaction as compared to traditional catalysts. Described herein are supported catalysts and methods of using the catalysts for the dry reforming of methane to synthesis gas, with the supported catalysts in the present invention include a boron-treated cobalt catalyst disposed on an oxide support. Also described herein are processes for preparing the supported catalysts.

  2. Numerical investigation of high temperature synthesis gas premixed combustion via ANSYS Fluent

    Directory of Open Access Journals (Sweden)

    Pashchenko Dmitry

    2018-01-01

    Full Text Available A numerical model of the synthesis gas pre-mixed combustion is developed. The research was carried out via ANSYS Fluent software. Verification of the numerical results was carried out using experimental data. A visual comparison of the flame contours that obtained by the synthesis gas combustion for Re = 600; 800; 1000 was performed. A comparison of the wall temperature of the combustion chamber, obtained with the help of the developed model, with the results of a physical experiment was also presented. For all cases, good convergence of the results is observed. It is established that a change in the temperature of the syngas/air mixture at the inlet to the combustion chamber does not significantly affect the temperature of the combustion products due to the dissipation of the H2O and CO2 molecules. The obtained results are of practical importance for the design of heat engineering plants with thermochemical heat recovery.

  3. Reactions of synthesis gas on silica supported transition metal catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Niemelae, M. [VTT Chemical Technology, Espoo (Finland). Lab. of Industrial Chemistry

    1997-12-31

    The effect of catalyst precursor and composition on the activation of CO was investigated using CO hydrogenation as a test reaction. The interrelations of preparation, pretreatment, characteristics and activity were clarified. For Co/SiO{sub 2} catalyst, MgO promotion increased the CO adsorption capacity and the hydrogen uptake, although the extent of reduction for cobalt remained the same or decreased. The conversion per active metallic cobalt site consequently increased in conjunction with MgO promotion, while the effect on overall performance per 1 g of catalyst remained moderate. The precursor affected the performance of Co/SiO{sub 2} considerably. CO was more strongly adsorbed on catalysts of carbonyl origin than on those derived from cobalt nitrate, the activity thus being higher. Although the nitrate derived Co/SiO{sub 2} appeared both to retain its activity and to regain its adsorption capacity better than the catalysts of carbonyl origin, the performance of the latter was superior with time on stream. For tetranuclear cluster based Co-Ru and Co-Rh catalysts, rhodium or ruthenium was in contact with the support and cobalt was enriched on top. On Co-Ru/SiO{sub 2} ruthenium enhanced deactivation, and no benefits in activity or oxygenate selectivity were achieved relative to the monometallic catalysts of cluster origin. The Co-Rh/SiO{sub 2} catalysts were also less active than those derived from monometallic clusters, but they exhibited higher selectivities to oxygenated compounds due to the presence of active sites on the perimeter of the cobalt particles located on rhodium. The highest selectivity to oxygenates was achieved by changing the decomposition atmosphere of Rh{sub 4}(CO){sub 12}/SiO{sub 2} from hydrogen to carbon monoxide. The results also showed two types of active sites to be operative in the formation of oxygenates - one for ethanol and another for aldehydes. (orig.) 69 refs.

  4. Synthesis and Gas Phase Thermochemistry of Germanium-Containing Compounds

    Energy Technology Data Exchange (ETDEWEB)

    Classen, Nathan Robert [Iowa State Univ., Ames, IA (United States)

    2002-01-01

    The driving force behind much of the work in this dissertation was to gain further understanding of the unique olefin to carbene isomerization observed in the thermolysis of 1,1-dimethyl-2-methylenesilacyclobutane by finding new examples of it in other silicon and germanium compounds. This lead to the examination of a novel phenylmethylenesilacyclobut-2-ene, which did not undergo olefin to carbene rearrangement. A synthetic route to methylenegermacyclobutanes was developed, but the methylenegermacyclobutane system exhibited kinetic instability, making the study of the system difficult. In any case the germanium system decomposed through a complex mechanism which may not include olefin to carbene isomerization. However, this work lead to the study of the gas phase thermochemistry of a series of dialkylgermylene precursors in order to better understand the mechanism of the thermal decomposition of dialkylgermylenes. The resulting dialkylgermylenes were found to undergo a reversible intramolecular β C-H insertion mechanism.

  5. Oil-shale gasification for obtaining of gas for synthesis of aliphatic hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Strizhakova, Yu. [Samara State Univ. (Russian Federation); Avakyan, T.; Lapidus, A.L. [I.M. Gubkin Russian State Univ. of Oil and Gas, Moscow (Russian Federation)

    2011-07-01

    Nowadays, the problem of qualified usage of solid fossil fuels as raw materials for obtaining of motor fuels and chemical products is becoming increasingly important. Gasification with further processing of gaseous products is a one of possible ways of their use. Production of synthesis gas with H{sub 2}/CO ratio equal 2 is possible by gasification of oil-shale. This gas is converted into the mixture of hydrocarbons over cobalt catalyst at temperature from 160 to 210 C at atmospheric pressure. The hydrocarbons can be used as motor, including diesel, or reactive fuel. (orig.)

  6. Electricity generation from synthesis gas by microbial processes: CO fermentation and microbial fuel cell technology.

    Science.gov (United States)

    Kim, Daehee; Chang, In Seop

    2009-10-01

    A microbiological process was established to harvest electricity from the carbon monoxide (CO). A CO fermenter was enriched with CO as the sole carbon source. The DGGE/DNA sequencing results showed that Acetobacterium spp. were enriched from the anaerobic digester fluid. After the fermenter was operated under continuous mode, the products were then continuously fed to the microbial fuel cell (MFC) to generate electricity. Even though the conversion yield was quite low, this study proved that synthesis gas (syn-gas) can be converted to electricity with the aid of microbes that do not possess the drawbacks of metal catalysts of conventional methods.

  7. Fischer Indole Synthesis in the Gas Phase, the Solution Phase, and at the Electrospray Droplet Interface.

    Science.gov (United States)

    Bain, Ryan M; Ayrton, Stephen T; Cooks, R Graham

    2017-07-01

    Previous reports have shown that reactions occurring in the microdroplets formed during electrospray ionization can, under the right conditions, exhibit significantly greater rates than the corresponding bulk solution-phase reactions. The observed acceleration under electrospray ionization could result from a solution-phase, a gas-phase, or an interfacial reaction. This study shows that a gas-phase ion/molecule (or ion/ion) reaction is not responsible for the observed rate enhancement in the particular case of the Fischer indole synthesis. The results show that the accelerated reaction proceeds in the microdroplets, and evidence is provided that an interfacial process is involved. Graphical Abstract GRAPHICAL ABSTRACT TEXT HERE] -->.

  8. Optimization of a corn steep medium for production of ethanol from synthesis gas fermentation by Clostridium ragsdalei.

    Science.gov (United States)

    Saxena, Jyotisna; Tanner, Ralph S

    2012-04-01

    Fermentation of biomass derived synthesis gas to ethanol is a sustainable approach that can provide more usable energy and environmental benefits than food-based biofuels. The effects of various medium components on ethanol production by Clostridium ragsdalei utilizing syngas components (CO:CO(2)) were investigated, and corn steep liquor (CSL) was used as an inexpensive nutrient source for ethanol production by C. ragsdalei. Elimination of Mg(2+), NH(4) (+) and PO(4) (3-) decreased ethanol production from 38 to 3.7, 23 and 5.93 mM, respectively. Eliminating Na(+), Ca(2+), and K(+) or increasing Ca(2+), Mg(2+), K(+), NH(4) (+) and PO(4) (3-) concentrations had no effect on ethanol production. However, increased Na(+) concentration (171 mM) inhibited growth and ethanol production. Yeast extract (0.5 g l(-1)) and trace metals were necessary for growth of C. ragsdalei. CSL alone did not support growth and ethanol production. Nutrients limiting in CSL were trace metals, NH(4) (+) and reducing agent (Cys: cysteine sulfide). Supplementation of trace metals, NH(4) (+) and CyS to CSL (20 g l(-1), wet weight basis) yielded better growth and similar ethanol production as compared to control medium. Using 10 g l(-1), the nutritional limitation led to reduced ethanol production. Higher concentrations of CSL (50 and 100 g l(-1)) were inhibitory for cell growth and ethanol production. The CSL could replace yeast extract, vitamins and minerals (excluding NH(4) (+)). The optimized CSL medium produced 120 and 50 mM of ethanol and acetate, respectively. The CSL could provide as an inexpensive source of most of the nutrients required for the syngas fermentation, and thus could improve the economics of ethanol production from biomass derived synthesis gas by C. ragsdalei.

  9. Enzymatic Synthesis of Fatty Hydroxamic Acid Derivatives Based on Palm Kernel Oil

    Directory of Open Access Journals (Sweden)

    Sidik Silong

    2011-08-01

    Full Text Available Fatty hydroxamic acid derivatives were synthesized using Lipozyme TL IM catalyst at biphasic medium as the palm kernel oil was dissolved in hexane and hydroxylamine derivatives were dissolved in water: (1 N-methyl fatty hydroxamic acids (MFHAs; (2 N-isopropyl fatty hydroxamic acids (IPFHAs and (3 N-benzyl fatty hydroxamic acids (BFHAs were synthesized by reaction of palm kernel oil and N-methyl hydroxylamine (N-MHA, N-isopropyl hydroxylamine (N-IPHA and N-benzyl hydroxylamine (N-BHA, respectively. Finally, after separation the products were characterized by color testing, elemental analysis, FT-IR and 1H-NMR spectroscopy. For achieving the highest conversion percentage of product the optimum molar ratio of reactants was obtained by changing the ratio of reactants while other reaction parameters were kept constant. For synthesis of MFHAs the optimum mol ratio of N-MHA/palm kernel oil = 6/1 and the highest conversion was 77.8%, for synthesis of IPFHAs the optimum mol ratio of N-IPHA/palm kernel oil = 7/1 and the highest conversion was 65.4% and for synthesis of BFHAs the optimum mol ratio of N-BHA/palm kernel oil = 7/1 and the highest conversion was 61.7%.

  10. Synthesis and preliminary biological evaluations of (+)-isocampholenic acid-derived amides.

    Science.gov (United States)

    Grošelj, Uroš; Golobič, Amalija; Knez, Damijan; Hrast, Martina; Gobec, Stanislav; Ričko, Sebastijan; Svete, Jurij

    2016-08-01

    The synthesis of two novel (+)-isocampholenic acid-derived amines has been realized starting from commercially available (1S)-(+)-10-camphorsulfonic acid. The novel amines as well as (+)-isocampholenic acid have been used as building blocks in the construction of a library of amides using various aliphatic, aromatic, and amino acid-derived coupling partners using BPC and CDI as activating agents. Amide derivatives have been assayed against several enzymes that hold potential for the development of new drugs to battle bacterial infections and Alzheimer's disease. Compounds 20c and 20e showed promising selective sub-micromolar inhibition of human butyrylcholinesterase [Formula: see text] ([Formula: see text] values [Formula: see text] and [Formula: see text], respectively).

  11. TECHNICAL AND ECONOMICAL ASSESSMENT OF USING PEAT GAS SYNTHESIS IN POWER ENGINEERING

    OpenAIRE

    Карвацький, Антон Янович

    2016-01-01

    Nowadays more and more attention in the world is paid for technology of using low-calorie fuels. They are associated with the processes of pyrolysis, gasification, production of gas synthesis and diesel fuel.In general, gasification technology is developing very well. There are many examples of successful commercial and practical realization of such projects. Examples of such developments commercialization from using of gasification process for electricity and heat production can be used in s...

  12. Thioxopyrimidine in Heterocyclic Synthesis I: Synthesis of Some Novel 6-(Heteroatom-substituted-(thiopyrimidine Derivatives

    Directory of Open Access Journals (Sweden)

    Yuh-Wen Ho

    2013-01-01

    Full Text Available A series of novel N-cycloalkanes, morpholine, piperazines, pyrazole, pyrimidine, benzimidazolo[1,2-a]pyrimidine, 1,2,3,4-tetrazolo[1,5-a]pyrimidine, azopyrazolo[1,5- a]pyrimidine, pyrimido[4', 5':3,4]pyrazolo[1,5-a]pyrimidines and pyridine derivatives incorporating a 5-cyano-4-methyl-2-phenyl-(thiopyrimidine moiety were obtained by the intramolecular cyclization of 6-methylthio-pyrimidine, 6-(benzoylmethylthio- pyrimidine and 2-[(5-cyano-4-methyl-2-phenylpyrimidin-6-ylthio]-3-dimethyl- amino-1-phenyl-prop-2-en-1-one with appropriate amines and enaminone compounds, respectively. The structure of all new synthesized compounds was established from their spectral data, elemental analysis and the X-ray crystal analysis.

  13. Novel Fluorinated Indanone, Tetralone and Naphthone Derivatives: Synthesis and Unique Structural Features

    Directory of Open Access Journals (Sweden)

    Joseph C. Sloop

    2012-02-01

    Full Text Available Several fluorinated and trifluoromethylated indanone, tetralone and naphthone derivatives have been prepared via Claisen condensations and selective fluorinations in yields ranging from 22–60%. In addition, we report the synthesis of new, selectively fluorinated bindones in yields ranging from 72–92%. Of particular interest is the fluorination and trifluoroacetylation regiochemistry observed in these fluorinated products. We also note unusual transformations including a novel one pot, dual trifluoroacetylation, trifluoroacetylnaphthone synthesis via a deacetylation as well as an acetyl-trifluoroacetyl group exchange. Solid-state structural features exhibited by these compounds were investigated using crystallographic methods. Crystallographic results, supported by spectroscopic data, show that trifluoroacetylated ketones prefer a chelated cis-enol form whereas fluorinated bindone products exist primarily as the cross-conjugated triketo form.

  14. Chiral thiazoline and thiazole building blocks for the synthesis of peptide-derived natural products.

    Science.gov (United States)

    Just-Baringo, Xavier; Albericio, Fernando; Alvarez, Mercedes

    2014-01-01

    Thiazoline and thiazole heterocycles are privileged motifs found in numerous peptide-derived natural products of biological interest. During the last decades, the synthesis of optically pure building blocks has been addressed by numerous groups, which have developed a plethora of strategies to that end. Efficient and reliable methodologies that are compatible with the intricate and capricious architectures of natural products are a must to further develop their science. Structure confirmation, structure-activity relationship studies and industrial production are fields of paramount importance that require these robust methodologies in order to successfully bring natural products into the clinic. Today's chemist toolbox is assorted with many powerful methods for chiral thiazoline and thiazole synthesis. Ranging from biomimetic approaches to stereoselective alkylations, one is likely to find a suitable method for their needs.

  15. Synthesis and characterization of ester and amide derivatives of titanium(IV) carboxymethylphosphonate

    International Nuclear Information System (INIS)

    Melánová, Klára; Beneš, Ludvík; Trchová, Miroslava; Svoboda, Jan; Zima, Vítězslav

    2013-01-01

    A set of layered ester and amide derivatives of titanium(IV) carboxymethylphosphonate was prepared by solvothermal treatment of amorphous titanium(IV) carboxymethylphosphonate with corresponding 1-alkanols, 1,ω-alkanediols, 1-aminoalkanes, 1,ω-diaminoalkanes and 1,ω-amino alcohols and characterized by powder X-ray diffraction, IR spectroscopy and thermogravimetric analysis. Whereas alkyl chains with one functional group form bilayers tilted to the layers, 1,ω-diaminoalkanes and most of 1,ω-alkanediols form bridges connecting the adjacent layers. In the case of amino alcohols, the alkyl chains form bilayer and either hydroxyl or amino group is used for bonding. This simple method for the synthesis of ester and amide derivatives does not require preparation of acid chloride derivative as a precursor or pre-intercalation with alkylamines and can be used also for the preparation of ester and amide derivatives of titanium carboxyethylphosphonate and zirconium carboxymethylphosphonate. - Graphical abstract: Ester and amide derivatives of layered titanium carboxymethylphosphonate were prepared by solvothermal treatment of amorphous solid with alkanol or alkylamine. - Highlights: • Ester and amide derivatives of titanium carboxymethylphosphonate. • Solvothermal treatment of amorphous solid with alkanol or alkylamine. • Ester and amide formation confirmed by IR spectroscopy

  16. Synthesis and antibacterial characterization of sustainable nanosilver using naturally-derived macromolecules

    Energy Technology Data Exchange (ETDEWEB)

    Osonga, Francis J.; Kariuki, Victor M.; Yazgan, Idris; Jimenez, Apryl; Luther, David; Schulte, Jürgen; Sadik, Omowunmi A., E-mail: osadik@binghamton.edu

    2016-09-01

    Greener nanosynthesis utilizes fewer amounts of materials, water, and energy; while reducing or replacing the need for organic solvents. A novel approach is presented using naturally-derived flavonoids including Quercetin pentaphosphate (QPP), Quercetin sulfonic acid (QSA) and Apigenin Triphosphate (ATRP). These water soluble, phosphorylated flavonoids were utilized both as reducing agent and stabilizer. The synthesis was achieved at room temperature using water as a solvent and it requires no capping agents. The efficiency of the resulting silver nanoparticle synthesis was compared with naturally-occurring flavonoid such as Quercetin (QCR). Results show that QCR reduced Ag{sup +} faster followed by QPP, QSA and ATRP respectively. This is the first evidence of direct utilization of QCR for synthesis of silver nanoparticles (AgNPs) in water. The percentage conversion of Ag{sup +} to Ag{sup 0} was determined to be 96% after 35 min. The synthesized nanoparticles were characterized using Transmission electron microscopy (TEM), Energy dispersive absorption spectroscopy (EDS), UV–vis spectroscopy, High resolution TEM (HR-TEM) with selected area electron diffraction (SAED). The particle sizes ranged from 2 to 80 nm with an average size of 22 nm and in the case of ATRP, the nanoparticle shapes varied from spherical to hexagonal with dispersed particle size ranging from 2 to 30 nm. Crystallinity was confirmed by XRD and the SAED of (111), (200), and the fringes observed in HRTEM images. Results were in agreement with the UV resonance peaks of 369–440 nm. The particles also exhibit excellent antibacterial activity against Staphylococcus epidermidis, Escherichia coli and Citrobacter freundii in water. - Highlights: • Greener nanosilver prepared using flavonoid derivatives • Synthesized nanosilver exhibits exhibit antibacterial activity. • Approach suitable for industrial synthesis.

  17. Integration of Fermentation and Organic Synthesis: Studies of Roquefortine C and Biosynthetic Derivatives

    Science.gov (United States)

    Gober, Claire Marie

    Roquefortine C is one of the most ubiquitous indoline alkaloids of fungal origin. It has been isolated from over 30 different species of Penicillium fungi and has garnered attention in recent years for its role as a biosynthetic precursor to the triazaspirocyclic natural products glandicoline B, meleagrin, and oxaline. The triazaspirocyclic motif, which encompasses three nitrogen atoms attached to one quaternary carbon forming a spirocyclic scaffold, is a unique chemical moiety that has been shown to impart a wide array of biological activity, from anti-bacterial activity and antiproliferative activity against cancer cell lines to anti-biofouling against marine organisms. Despite the promise of these compounds in the pharmaceutical and materials industries, few syntheses of triazaspirocycles exist in the literature. The biosynthesis of roquefortine C-derived triazaspirocycles, however, provides inspiration for the synthesis of these compounds, namely through a nitrone-promoted transannular rearrangement. This type of internal rearrangement has never been carried out synthetically and would provide an efficient stereoselective synthesis of triazaspirocycles. This work encompasses efforts towards elucidating the biosynthetic pathway of roquefortine C-derived triazaspirocycles as well as synthetic efforts towards the construction of triazaspirocycles. Chapter 1 will discuss a large-scale fermentation procedure for the production of roquefortine C from Penicillium crustosum. Chapters 2 and 3 explore (through enzymatic and synthetic means, respectively) the formation of the key indoline nitrone moiety required for the proposed transannular rearrangement. Finally, chapter 4 will discuss synthetic efforts towards the synthesis of triazaspirocycles. This work has considerably enhanced our understanding of the roquefortine C biosynthetic pathway and the unique chemistry of this natural product, and our efforts towards the synthesis of triazaspirocycles will facilitate the

  18. GlidArc-assisted production of synthesis gas from various carbonaceous feedstocks

    International Nuclear Information System (INIS)

    Czernichowski, A.; Czernichowski, P.; Czernichowski, M.

    2003-01-01

    Pure Hydrogen or its mixture with Carbon Monoxide (called Synthesis Gas) will be massively extracted from various fossil or renewable feedstocks. Such matters contain contaminants (principally Sulphur) that make conventional catalytic reforming technologies very difficult to run without a prior deep cleaning of the feeds in order to avoid the reformer's catalyst poisoning. We propose a non-catalytic process in which almost any carbonaceous feed is converted into the Synthesis Gas in a presence of high-voltage discharges (called GlidArc) that assist the exothermic Partial Oxidation POX). The unique oxidant is air. This contribution presents some of our tests with natural gas, cyclohexane, heptane, toluene, various gasolines, and various diesel oils (including logistic ones). In two separate contributions to this Conference we present our more expanded studies on the GlidArc-assisted POX reforming of commercial propane and rapeseed oil (canola). Our reactors (1- or 2-Liter scale) work at atmospheric pressure and need less than 0.5 kW electric power (rather about 0.1 kW) to produce up to 9 m 3 (n)/h of Nitrogen-diluted SynGas containing up to 27% of H 2 and up to 23% of CO. Such assisting power represents roughly less than 5% (rather around 2%) with respect to the Lower Heating Value of produced Synthesis Gas (up to 11 kW). Recycling such relatively small portion of the power is an acceptable compromise. All tested feeds are totally reformed. No soot is observed at a sufficient O/C ratio. (author)

  19. Synthesis and enhanced neuroprotective activity of C60-based ebselen derivatives

    International Nuclear Information System (INIS)

    Liu, X.-F.; Guan, W.-C.; Ke, W.-S.

    2007-01-01

    A C 60 -based ebselen derivative 4 was synthesized through the cycloaddition of C 60 with the azide (3) containing the ebselen component. It was obtained in a four-step synthesis starting from 2-(chloroseleno)benzoyl chloride and 2-(2-aminoethoxy)ethanol in 53% yield (based on consumed C 60 ). Its structure was characterized by 1 H NMR, 13 C NMR, IR, UV, and FAB-MS. To verify that the C 60 -based ebselen derivative 4 had enhanced antioxidative and neuroprotective activity, the C 60 derivative 5 and the ebselen derivative 6 were selected to treat cortical neuronal cells using the same procedures as with the C 60 -based ebselen derivative 4. The cellular viability of different derivative treatment groups was estimated by LDH leakage assay and MTT assay. At the same final concentration (30 μmol/L), the results showed that the antioxidative and protective potencies of the C 60 -based ebselen derivative 4 (MTT (OD) 0.340 ± 0.035, LDH release (UL -1 ) 4.80 ± 0.16) against H 2 O 2 -mediated neuronal injury have an advantage over those of C 60 derivative 5 (MTT (OD) 0.297 ± 0.036, LDH release (UL -1 ) 5.37 ± 0.31) and ebselen derivative 6 (MTT (OD) 0.267 ± 0.027, LDH release (UL -1 ) 5.85 ± 0.26). Correspondingly, the GPX activity of 4 (1.62 U/μmol) was higher than that of 5 (0.77 U/μmol) and 6 (1.24 U/μmol). These findings demonstrate that the incorporation of two components with similar biological activity (C 60 component and ebselen component) may be a desirable way of obtaining a new and more biologically effective C 60 -based compound. (author)

  20. Synthesis of biomass derived carbon materials for environmental engineering and energy storage applications

    Science.gov (United States)

    Huggins, Mitchell Tyler

    Biomass derived carbon (BC) can serve as an environmentally and cost effective material for both remediation and energy production/storage applications. The use of locally derived biomass, such as unrefined wood waste, provides a renewable feedstock for carbon material production compared to conventional unrenewable resources like coal. Additionally, energy and capital cost can be reduced through the reduction in transport and processing steps and the use of spent material as a soil amendment. However, little work has been done to evaluate and compare biochar to conventional materials such as granular activated carbon or graphite in advanced applications of Environmental Engineering. In this work I evaluated the synthesis and compared the performance of biochar for different applications in wastewater treatment, nutrient recovery, and energy production and storage. This includes the use of biochar as an electrode and filter media in several bioelectrochemical systems (BES) treating synthetic and industrial wastewater. I also compared the treatment efficiency of granular biochar as a packed bed adsorbent for the primary treatment of high strength brewery wastewater. My studies conclude with the cultivation of fungal biomass to serve as a template for biochar synthesis, controlling the chemical and physical features of the feedstock and avoiding some of the limitations of waste derived materials.

  1. Novel Routes to Ethylene Glycol Synthesis via Acid-Catalyzed Carbonylation of Formaldehyde and Dimethoxymethane

    OpenAIRE

    Celik, Fuat Emin

    2010-01-01

    Carbon-carbon bond forming carbonylation reactions were investigated as candidates to replace ethene epoxidation as the major source of ethylene glycol production. This work was motivated by the potentially lower cost of carbon derived from synthesis gas as compared to ethylene. Synthesis gas can be produced from relatively abundant and cheap natural gas, coal, and biomass resources whereas ethylene is derived from increasingly scarce and expensive crude oil. From synthesis gas, a range of...

  2. Simulation-Optimization Framework for Synthesis and Design of Natural Gas Downstream Utilization Networks

    Directory of Open Access Journals (Sweden)

    Saad A. Al-Sobhi

    2018-02-01

    Full Text Available Many potential diversification and conversion options are available for utilization of natural gas resources, and several design configurations and technology choices exist for conversion of natural gas to value-added products. Therefore, a detailed mathematical model is desirable for selection of optimal configuration and operating mode among the various options available. In this study, we present a simulation-optimization framework for the optimal selection of economic and environmentally sustainable pathways for natural gas downstream utilization networks by optimizing process design and operational decisions. The main processes (e.g., LNG, GTL, and methanol production, along with different design alternatives in terms of flow-sheeting for each main processing unit (namely syngas preparation, liquefaction, N2 rejection, hydrogen, FT synthesis, methanol synthesis, FT upgrade, and methanol upgrade units, are used for superstructure development. These processes are simulated using ASPEN Plus V7.3 to determine the yields of different processing units under various operating modes. The model has been applied to maximize total profit of the natural gas utilization system with penalties for environmental impact, represented by CO2eq emission obtained using ASPEN Plus for each flowsheet configuration and operating mode options. The performance of the proposed modeling framework is demonstrated using a case study.

  3. Synthesis of Gibberellic Acid Derivatives and Their Effects on Plant Growth

    Directory of Open Access Journals (Sweden)

    Hao Tian

    2017-04-01

    Full Text Available A series of novel C-3-OH substituted gibberellin derivatives bearing an amide group were designed and synthesized from the natural product gibberellic acid (GA3. Their activities on the plant growth regulation of rice and Arabidopsis were evaluated in vivo. Among these compounds, 10d and 10f exhibited appreciable inhibitory activities on rice (48.6% at 100 μmol/L and Arabidopsis (41.4% at 100 μmol/L, respectively. These results provide new insights into the design and synthesis of potential plant growth regulators.

  4. Synthesis and evaluation of the plant growth regulator property of indolic compounds derived from safrole

    International Nuclear Information System (INIS)

    Marchi, Irineu; Rebelo, Ricardo Andrade; Rosa, Flavia A. Fernandes da; Maiochi, Riceli A.

    2007-01-01

    The present work describes the use of piperonal, a derivative of the secondary metabolite safrole, for the synthesis of new 5,6-methylenedioxy substituted indole carboxylic acids structurally related to the indol-3-yl-acetic acid (AIA, I). The route comprises six steps beginning with piperonal with an overall yield of 19%. Compound IX was tested towards its plant growth regulator properties in bioassays specific for auxine activity. The in vitro assays were performed in a germination chamber and were of two types: root growth in germinated seeds of Lactuca sativa, Cucumbis sativus and Raphanus sativus and peciole biotest using Phaseolus vulgaris. (author)

  5. Synthesis and spectroscopic characterization of a fluorescent pyrrole derivative containing electron acceptor and donor groups

    Science.gov (United States)

    Almeida, A. K. A.; Monteiro, M. P.; Dias, J. M. M.; Omena, L.; da Silva, A. J. C.; Tonholo, J.; Mortimer, R. J.; Navarro, M.; Jacinto, C.; Ribeiro, A. S.; de Oliveira, I. N.

    2014-07-01

    The synthesis and fluorescence characterization of a new pyrrole derivative (PyPDG) containing the electron donor-acceptor dansyl substituent is reported. The effects of temperature and solvent polarity on the steady-state fluorescence of this compound are investigated. Our results show that PyPDG exhibits desirable fluorescent properties which makes it a promising candidate to be used as the photoactive material in optical thermometry and thermography applications. Further, the electrochemical and emission properties of polymeric films obtained from the oxidation polymerization of PyPDG are also analyzed.

  6. Synthesis and Characterization of New Polyamides from 1,2-Bis hydrazine Derivatives

    International Nuclear Information System (INIS)

    Salaha, A.; Abdel-Bary, E.M.; Kandilea, N.G.

    2005-01-01

    Preparation of polyamides having different chemical structures allows obtaining new materials with different mechanical and physical properties. The difference in the chemical structure depends mainly on the starting reactants used in condensation polymerization of polyamides. In this paper the synthesis of new polyamides based on the condensation polymerization of 1,2- Bis(3-carboxyacryloyl or carboxybenzoyl) hydrazine derivatives and various diamines has been described. The polymers obtained were characterized using spectroscopic and X-ray analysis. Besides thermal stability and electrical conductivity have been evaluated and correlated with the chemical structure of the polyamides obtained

  7. Biological evaluation and simple method for the synthesis of tetrahydrobenzo[a]xanthenes-11-one derivatives

    Directory of Open Access Journals (Sweden)

    Ali Akbari

    2017-01-01

    Full Text Available A simple method for the synthesis of Tetrahydrobenzo[a]xanthenes-11-one derivatives in the presence of BF3.SiO2, and its antibacterial activity was assessed against Pseudomonas syringae, Xanthomonas citi and Pectobacterium carotovorum. The structure of the isolated compounds has been determined by means of 1H/13C NMR and FT-IR spectroscopy. The reactions were carried out in water at room temperature for 5 h. This method has some advantages such as good to excellent yield, mild reaction condition, ease of operation and workup, high product purity and green process.

  8. Swarm intelligence for multi-objective optimization of synthesis gas production

    Science.gov (United States)

    Ganesan, T.; Vasant, P.; Elamvazuthi, I.; Ku Shaari, Ku Zilati

    2012-11-01

    In the chemical industry, the production of methanol, ammonia, hydrogen and higher hydrocarbons require synthesis gas (or syn gas). The main three syn gas production methods are carbon dioxide reforming (CRM), steam reforming (SRM) and partial-oxidation of methane (POM). In this work, multi-objective (MO) optimization of the combined CRM and POM was carried out. The empirical model and the MO problem formulation for this combined process were obtained from previous works. The central objectives considered in this problem are methane conversion, carbon monoxide selectivity and the hydrogen to carbon monoxide ratio. The MO nature of the problem was tackled using the Normal Boundary Intersection (NBI) method. Two techniques (Gravitational Search Algorithm (GSA) and Particle Swarm Optimization (PSO)) were then applied in conjunction with the NBI method. The performance of the two algorithms and the quality of the solutions were gauged by using two performance metrics. Comparative studies and results analysis were then carried out on the optimization results.

  9. Modeling of a three-phase reactor for bitumen-derived gas oil hydrotreating

    International Nuclear Information System (INIS)

    Chacon, R.; Canale, A.; Bouza, A.; Sanchez, Y.

    2012-01-01

    A three-phase reactor model for describing the hydrotreating reactions of bitumen-derived gas oil was developed. The model incorporates the mass-transfer resistance at the gas-liquid and liquid-solid interfaces and a kinetic rate expression based on a Langmuir-Hinshelwood-type model. We derived three correlations for determining the solubility of hydrogen (H 2 ), hydrogen sulfide (H 2 S) and ammonia (NH 3 ) in hydrocarbon mixtures and the calculation of the catalyst effectiveness factor was included. Experimental data taken from the literature were used to determine the kinetic parameters (stoichiometric coefficients, reaction orders, reaction rate and adsorption constants for hydrodesulfuration (HDS) and hydrodenitrogenation (HDN)) and to validate the model under various operating conditions. Finally, we studied the effect of operating conditions such as pressure, temperature, LHSV, H 2 /feed ratio and the inhibiting effect of H 2 S on HDS and NH 3 on HDN. (author)

  10. Synthesis, characterization and biological behavior of some Schiff's and Mannich base derivatives of Lamotrigine

    Directory of Open Access Journals (Sweden)

    A.A. Kulkarni

    2017-02-01

    Full Text Available A series of various Schiff's and Mannich base derivatives (N1–2 & ND1–6 of Lamotrigine with isatin and substituted isatin were synthesized to get more potent anticonvulsant agents. The starting material for the synthesis of various new Schiff's and Mannich base derivatives was isatin (1H-indole- 2, 3-dione which in turn was prepared from substituted isonitrosoacetanilide using aniline. Lamotrigine reacts with isatin & substituted isatin gave Schiff's bases (N1–2 which on reaction with various secondary amines (dimethylamine, diethylamine, morpholine produced Mannich bases (ND1–6. The structures of newly synthesized compounds were characterized by using TLC, UV, FT-IR, 1HNMR and studied for their anticonvulsant activity. Anticonvulsant activity of all the derivatives was evaluated by MES method using phenobarbitone sodium & Lamotrigine as standard drugs and % reduction of time spent by animals in extension, flexion, clonus, and stupor phase were noted. Compounds ND-4 and ND-6 showed significant anticonvulsant activity when compared with that of standard drugs. The remaining all compounds show moderate activity. Biological activity data of the synthesized derivatives revealed that, the synthesized derivatives are good anticonvulsant agents as compared to Lamotrigine.

  11. Synthesis, characterization and biological activity of C6-Schiff bases derivatives of chitosan.

    Science.gov (United States)

    Xu, Ruibo; Aotegen, Bayaer; Zhong, Zhimei

    2017-12-01

    C 6 -Schiff bases derivatives of chitosan were synthesized for the first time. C 2 -amino groups and C 3 -hydroxy groups were firstly protected by CuSO 4 ·5H 2 O, and the C 6 -hydroxy was then transformed into aldehyde, which then reacted with anilines through nucleophilic addition to introduce the CN group at C 6 -position in chitosan chain. Finally, C 6 -Schiff bases derivatives of chitosan were got by the deprotection of C 2 -NH 2 with cation exchange resin. The structures and properties of the new synthesized products were characterized by Fourier transform infrared spectroscopy, 13 C NMR, SEM image, and elemental analysis. The antibacterial activities of derivatives were tested in the experiment, and the results showed that the prepared chitosan derivatives had significantly improved antibacterial activity toward Staphylococcus aureus and Escherichia coli. The Cytotoxicity test showed that the prepared chitosan derivatives had low Cytotoxicity, compared with chitosan and C 2 -benzaldehyde Schiff bases of chitosan. This paper allowed a new method for the synthesis of Schiff bases of chitosan, which was enlightening. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. Synthesis of ellagic acid and its 4,4'-di-Ο-alky derivatives from gallic acid

    OpenAIRE

    Alam, Ashraful; 高口, 豊; 坪井, 貞夫

    2005-01-01

    Synthesis of ellagic acid and its 4,4'-di-Ο-alkyl derivatives from gallic acid is described. Ellagic acid is prepared by oxidative coupling of gallic acid with ο-chloranil. Functionalized methyl bormogallate underwent Ullmann coupling to give the biphenyl that upon lactonization resulted in the ellagic acid and its alkoxy derivatives.

  13. Synthesis of Renewable Lubricant Alkanes from Biomass-Derived Platform Chemicals.

    Science.gov (United States)

    Gu, Mengyuan; Xia, Qineng; Liu, Xiaohui; Guo, Yong; Wang, Yanqin

    2017-10-23

    The catalytic synthesis of liquid alkanes from renewable biomass has received tremendous attention in recent years. However, bio-based platform chemicals have not to date been exploited for the synthesis of highly branched lubricant alkanes, which are currently produced by hydrocracking and hydroisomerization of long-chain n-paraffins. A selective catalytic synthetic route has been developed for the production of highly branched C 23 alkanes as lubricant base oil components from biomass-derived furfural and acetone through a sequential four-step process, including aldol condensation of furfural with acetone to produce a C 13 double adduct, selective hydrogenation of the adduct to a C 13 ketone, followed by a second condensation of the C 13 ketone with furfural to generate a C 23 aldol adduct, and finally hydrodeoxygenation to give highly branched C 23 alkanes in 50.6 % overall yield from furfural. This work opens a general strategy for the synthesis of high-quality lubricant alkanes from renewable biomass. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Synthesis of acetylcholine from choline derived from phosphatidylcholine in a human neuronal cell line

    International Nuclear Information System (INIS)

    Blusztajn, J.K.; Liscovitch, M.; Richardson, U.I.

    1987-01-01

    Cholinergic neurons are unique among cells since they alone utilize choline not only as a component of major membrane phospholipids, such as phosphatidylcholine (Ptd-Cho), but also as a precursor of their neurotransmitter acetylcholine (AcCho). It has been hypothesized that choline-phospholipids might serve as a storage pool of choline for AcCho synthesis. The selective vulnerability of cholinergic neurons in certain neurodegenerative diseases (e.g., Alzheimer disease, motor neuron disorders) might result from the abnormally accelerated liberation of choline (to be used a precursor of AcCho) from membrane phospholipids, resulting in altered membrane composition and function and compromised neuronal viability. However, the proposed metabolic link between membrane turnover and AcCho synthesis has been difficult to demonstrate because of the heterogeneity of the preparations used. Here the authors used a population of purely cholinergic cells (human neuroblastomas, LA-N-2), incubated in the presence of [methyl- 3 H]methionine to selectively label PtdCho synthesized by methylation of phosphatidylethanolamine, the only pathway of de novo choline synthesis. Three peaks of radioactive material that cochromatographed with authentic AcCho, choline, and phosphocholine were observed when the water-soluble metabolites of the [ 3 H]PtdCho were purified by high-performance liquid chromatography. The results demonstrate that AcCho can be synthesized from choline derived from the degradation of endogenous PtdCho formed de novo by methylation of phosphatidylethanolamine

  15. SYNTHESIS OF AZO COMPOUNDS DERIVATIVE FROM EUGENOL AND ITS APPLICATION AS A TITRATION INDICATOR

    Directory of Open Access Journals (Sweden)

    Bambang Purwono

    2010-06-01

    Full Text Available The synthesis of azo compounds from eugenol has been carried out by diazotation reaction. The diazonium salt was produced by reaction of aniline and sodium nitrite in acid condition at 0-5 °C temperature to yield benzenediazonium chloride salt. The salt was then reacted with eugenol to produce the azo derivatives. The azo product was analyzed by IR, 1H-NMR, dan GC-MS spectrometer. The results showed that the reaction of benzenediazonium chloride with eugenol gave 4-allyl-2-methoxy-6-hydroxyazobenzene in 34.27% yield for 30 minutes reaction. The derivative of azo compound was dissolved in ethanol and then the color changing was observed in range of pH 9.8-11.1 from yellow to red. Application for titration indicator for acetic acid titrated with sodium hydroxide showed error less than 3.20% compared with phenol phtaline indicator.   Keywords: Eugenol, Azo compound, titration indicator

  16. The effect of purine phosphonomethoxyalkyl derivatives on DNA synthesis in Cho Chinese hamster cells

    Energy Technology Data Exchange (ETDEWEB)

    Stetina, R [Institute of Experimental Medicine, Laboratory of Developmental Toxicology, Academy of Sciences of Czech Republic, 51783 Olesnice v Orlickych horach (Czech Republic); Votruba, I; Holy, A; Merta, A [Institute of Organic Chemistry and Biochemistry, Academy of Sciences of Czech Republic (Czech Republic)

    1994-12-31

    The inhibition of incorporation of {sup 3}H-thymidine and the changes of the rate of nascent DNA chain elongation were investigated in Cho Chinese hamster cells treated with (S)-(3-hydroxy-2-phosphonomethoxypropyl) (HPMP) and N-(2-phosphonomethoxyethyl) (PME) derivatives of adenine (A), guanine (G) and 2,6-diaminopurine (DAP). No direct correlation was observed in PME and HPMP derivatives between cytotoxicity, inhibition of {sup 3}H-thymidine incorporation and inhibition of nascent DNA chain elongation. The highest cytotoxicity and inhibition of DNA synthesis were caused by PMEG. The limited extent of inhibition of DNA elongation was encountered in the case of HPMPG and HPMPA. With PMEA, weak inhibition of elongation of DNA was observed only after a prolonged exposure (6 h). None of the investigated drugs induced DNA breaks. (author) 4 figs., 23 refs.

  17. Design, Synthesis and Evaluation of Ribose-modified Anilinopyrimidine Derivatives as EGFR Tyrosine Kinase Inhibitors

    Science.gov (United States)

    Hu, Xiuqin; Wang, Disha; Tong, Yi; Tong, Linjiang; Wang, Xia; Zhu, Lili; Xie, Hua; Li, Shiliang; Yang, You; Xu, Yufang

    2017-11-01

    The synthesis of a series of ribose-modified anilinopyrimidine derivatives was efficiently achieved by utilizing DBU or tBuOLi-promoted coupling of ribosyl alcohols with 2,4,5-trichloropyrimidine as key step. Preliminary biological evaluation of this type of compounds as new EGFR tyrosine kinase inhibitors for combating EGFR L858R/T790M mutant associated with drug resistance in the treatment of non-small cell lung cancer revealed that 3-N-acryloyl-5-O-anilinopyrimidine ribose derivative 1a possessed potent and specific inhibitory activity against EGFR L858R/T790M over WT EGFR. Based upon molecular docking studies of the binding mode between compound 1a and EGFR, the distance between the Michael receptor and the pyrimidine scaffold is considered as an important factor for the inhibitory potency and future design of selective EGFR tyrosine kinase inhibitors against EGFR L858R/T790M mutants.

  18. Synthesis of refractory organic matter in the ionized gas phase of the solar nebula.

    Science.gov (United States)

    Kuga, Maïa; Marty, Bernard; Marrocchi, Yves; Tissandier, Laurent

    2015-06-09

    In the nascent solar system, primitive organic matter was a major contributor of volatile elements to planetary bodies, and could have played a key role in the development of the biosphere. However, the origin of primitive organics is poorly understood. Most scenarios advocate cold synthesis in the interstellar medium or in the outer solar system. Here, we report the synthesis of solid organics under ionizing conditions in a plasma setup from gas mixtures (H2(O)-CO-N2-noble gases) reminiscent of the protosolar nebula composition. Ionization of the gas phase was achieved at temperatures up to 1,000 K. Synthesized solid compounds share chemical and structural features with chondritic organics, and noble gases trapped during the experiments reproduce the elemental and isotopic fractionations observed in primitive organics. These results strongly suggest that both the formation of chondritic refractory organics and the trapping of noble gases took place simultaneously in the ionized areas of the protoplanetary disk, via photon- and/or electron-driven reactions and processing. Thus, synthesis of primitive organics might not have required a cold environment and could have occurred anywhere the disk is ionized, including in its warm regions. This scenario also supports N2 photodissociation as the cause of the large nitrogen isotopic range in the solar system.

  19. Synthesis and electrochemistry of tri- and tetranuclear polypyridine derivations of ruthenium

    International Nuclear Information System (INIS)

    Francis, A.M.A.

    1990-01-01

    The synthesis of clusters of ruthenium is the focus of this work. The electrochemistry of metal cluster derivatives of ruthenium, iron and osmium are reviewed. The ability of these compounds to undergo more than one electron transfer reaction and to act as electron reservoirs is evident. The synthesis and characterisation of a range of polypyridine derivatives of [Ru 3 (CO) 12 ]; [Ru 3 (CO) 10 (napy)]; [Ru 3 (CO) 10 (bipy)]; [Ru 4 H 4 (CO) 12 ]; [Ru 4 H 4 (CO) 8 (bipy) 2 ] and [Ru 4 H 4 (CO) 10 (bipy)] were dealt with. The crystal structures of [Ru 3 (CO) 10 (napy)] and [Ru 4 H 4 (CO) 10 (bipy)] were also determined. The six compounds were fully investigated and a mechanism for their electrochemical reduction was postulated based on their observed experimental data, and that of the relevant compounds. The techniques used are also described and a brief introduction to the actual theory and practise of these techniques is discussed. 132 refs., 33 figs., 22 tabs

  20. Keratinocyte-derived laminin-332 protein promotes melanin synthesis via regulation of tyrosine uptake.

    Science.gov (United States)

    Chung, Heesung; Jung, Hyejung; Lee, Jung-Hyun; Oh, Hye Yun; Kim, Ok Bin; Han, Inn-Oc; Oh, Eok-Soo

    2014-08-01

    Melanocytes, which produce the pigment melanin, are known to be closely regulated by neighboring keratinocytes. However, how keratinocytes regulate melanin production is unclear. Here we report that melanin production in melanoma cells (B16F10 and MNT-1) was increased markedly on a keratinocyte-derived extracellular matrix compared with a melanoma cell-derived extracellular matrix. siRNA-mediated reduction of keratinocyte-derived laminin-332 expression decreased melanin synthesis in melanoma cells, and laminin-332, but not fibronectin, enhanced melanin content and α-melanocyte-stimulating hormone-regulated melanin production in melanoma cells. Similar effects were observed in human melanocytes. Interestingly, however, laminin-332 did not affect the expression or activity of tyrosinase. Instead, laminin-332 promoted the uptake of extracellular tyrosine and, subsequently, increased intracellular levels of tyrosine in both melanocytes and melanoma cells. Taken together, these data strongly suggest that keratinocyte-derived laminin-332 contributes to melanin production by regulating tyrosine uptake. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.

  1. Synthesis of some pyridine and pyrimidine derivatives via Michael-Addition

    International Nuclear Information System (INIS)

    El-Baih, Fatma E.M.; Al-Rasheed, Hessa H.; Al-Hazimi, Hassan M.

    2006-01-01

    Synthesis of pyridine and pyrimidine analogues 4 and 6-9 were achieved by Michael-addition of compounds containing either active methylene groups like, malononitrile , ethyl cyanoacetate and 1-tetralone or compounds containing active hydrogen atoms like, guanidine in the presence of an oxidizing agent and thiourea to 2-arylmethylidine-1-tetralone and 2-arylmethylidine-6-methoxy-1-tetralone (2) (enones). Addition of malononitrile in piperidine at room temperature to 2-amino-3-cyno-naphtho [1, 2-malonoitrile in sodium alkoxide or sodium hydroxide to 2 gave 4. Cyclization of 3a with acetic anhydride in the presence of conc. H2sO4 gave the naphtha-pyrano[2, 3-d]pyrimidin-8-one (5). Condensation of the pyrimidine thione derivatives 9 with chloroacetic acid gave the 3-oxobenzo[h]thiazoladino[2, 3-b]quinazoline derivatives (10), which were reacted through their active methylene groups with aromatic aldehydes to give the arylidine derivatives 11. These compounds were also prepared in one step by reacting 9 with chloroacetic acid and aromatic aldehydes. Condensation of 9 with 3-bromopropanoic acid gave 4-oxo-benzo[h]1, 3-thiazino[2, 3-b]quinazoline derivatives (12). The structures of the prepared compounds were mainly confirmed on the basis of spectroscopic methods. (author)

  2. All-gas-phase synthesis of UiO-66 through modulated atomic layer deposition

    Science.gov (United States)

    Lausund, Kristian Blindheim; Nilsen, Ola

    2016-11-01

    Thin films of stable metal-organic frameworks (MOFs) such as UiO-66 have enormous application potential, for instance in microelectronics. However, all-gas-phase deposition techniques are currently not available for such MOFs. We here report on thin-film deposition of the thermally and chemically stable UiO-66 in an all-gas-phase process by the aid of atomic layer deposition (ALD). Sequential reactions of ZrCl4 and 1,4-benzenedicarboxylic acid produce amorphous organic-inorganic hybrid films that are subsequently crystallized to the UiO-66 structure by treatment in acetic acid vapour. We also introduce a new approach to control the stoichiometry between metal clusters and organic linkers by modulation of the ALD growth with additional acetic acid pulses. An all-gas-phase synthesis technique for UiO-66 could enable implementations in microelectronics that are not compatible with solvothermal synthesis. Since this technique is ALD-based, it could also give enhanced thickness control and the possibility to coat irregular substrates with high aspect ratios.

  3. Synthesis of densely functionalized enantiopure indolizidines by ring-closing metathesis (RCM of hydroxylamines from carbohydrate-derived nitrones

    Directory of Open Access Journals (Sweden)

    Goti Andrea

    2007-12-01

    Full Text Available Abstract Background Indolizidine alkaloids widely occur in nature and display interesting biological activity. This is the reason for which their total synthesis as well as the synthesis of non-natural analogues still attracts the attention of many research groups. To establish new straightforward accesses to these molecules is therefore highly desirable. Results The ring closing metathesis (RCM of enantiopure hydroxylamines bearing suitable unsaturated groups cleanly afforded piperidine derivatives in good yields. Further cyclization and deprotection of the hydroxy groups gave novel highly functionalized indolizidines. The synthesis of a pyrroloazepine analogue is also described. Conclusion We have developed a new straightforward methodology for the synthesis of densely functionalized indolizidines and pyrroloazepine analogues in 6 steps and 30–60% overall yields from enantiopure hydroxylamines obtained straightforwardly from carbohydrate-derived nitrones.

  4. Process for the manufacture of a gas largely free of inert gases for synthesis. Verfahren zur Herstellung eines weitgehend inertfreien Gases zur Synthese

    Energy Technology Data Exchange (ETDEWEB)

    Eisenlohr, K H; Gaensslen, H; Kriebel, M; Tanz, H

    1983-11-10

    In a process for producing a gas largely free of inert gases for the synthesis of alcohols, particularly methanol, and of hydrocarbons from coal or heavy hydrocarbons by gasification under pressure with oxygen and steam, the crude gas is cooled, the impurities are removed by washing with methanol and the methanol is removed from the cold pure gas by molecular sieves. The pure gas is then cooled further by evaporation and methane is distilled from the liquid part while simultaneously obtaining the synthetic gas consisting of hydrogen and carbon monoxide which is largely free of methane. The methane is wholly or partly compressed and then split into carbon monoxide and hydrogen using steam and oxygen. The split gas is fed back and mixed with the synthesis gas or the partly cleaned crude gas. The synthesis gas heated to the ambient temperature, freed of impurities and free of methane is compressed to the required synthesis pressure.

  5. C60-based ebselen derivative: synthesis by bingel cyclopropanation and enhanced antioxidative and neuroprotective activity

    International Nuclear Information System (INIS)

    Xufeng Liu; Wenchao Guan; Wengshan Ke

    2007-01-01

    C 60 -based ebselen derivative 3 was synthesized through Bingel cyclopropanation of C 60 with the ebselen malonate 2. Compound 3 was obtained in 42% yield (based on consumed C 60 ) in a three-step synthesis starting from 2-(chloroseleno)benzoyl chloride and 2-(2aminoethoxy)ethanol. Its structure was confirmed by 1H NMR, 13 C NMR, IR, UV and FAB-MS spectroscopy analyses. In order to verify the enhanced antioxidative and neuroprotective activity of 3, a C 60 derivative (4), an ebselen derivative (2), and their mixture (4 plus 2 in equimolar ratio) were employed to treat cortical neuronal cells, following the same procedure used with 3 and at the same final concentration (30 μmol L -1 ). Cell viabilities of the four treated groups were estimated by LDH (lactic dehydrogenase) leakage and MTT (3-(4, 5-dimethylthiazole-2yl)-2,5-diphenyl-tetrazolium bromide) assays. Results showed that the antioxidative and protective activities of C 60 -based ebselen derivative 3 against H 2 O 2 -mediated neuronal injury (MTT(OD) 0.364 ± 0.028; LDH release (UL -1 ) 4.66 ± 0.28) were significantly higher than those of C 6 )0 derivative 4 (MTT(OD) 0.324 ± 0.025; LDH release (UL -1 ) 5.39 ± 0.17), ebselen derivative 2 (MTT(OD) 0.294 ± 0.021; LDH release (UL -1 ) 5.71 ± 0.27), and the mixture of 4 and 2 (MTT(OD) 0.310 ± 0.018; LDH release (UL -1 ) 5.54 ±0.39). These findings demonstrated that the combination of two molecular units with similar biological activities (C 60 and ebselen) may be a desirable way of obtaining new and more biologically effective C 60 -based compounds. (author)

  6. SYNTHESIS AND PHYSICAL-CHEMICAL PROPERTIES OF WATER-SOLUBLE 3-BENZYLXANTHINE DERIVATIVES

    Directory of Open Access Journals (Sweden)

    K. V. Аleksandrova

    2015-04-01

    Full Text Available Introduction Nowadays, research of novel biological active compounds with low toxicity, are carried out among different classes of organic compounds of natural and synthetic genesis. One of the main ways of these studies is search of water-soluble compounds – convenient objects for pharmacological researches. In recent years researchers paid attention to xanthine derivatives, because of their high variativity of possible chemical modification and ability to form different salts with wide spectrum of biological action. Thus, among water-soluble xanthine derivatives were found compounds with pronounced antioxidant, diuretic and analeptic properties. Primary methods of obtaining water-soluble xanthine derivatives are direct interaction of bases with xanthine molecule or insertion basic or acidic residues in positions 7 or 8 of xanthine bicycle. According from the above, search of biologically active compounds among water-soluble substituted xanthines is prospective and actual. The aim of the study was development of synthetic ways of obtaining novel water-soluble derivatives of 3-benzyl-8-methylxanthine and studying their physical and chemical properties. Material and methods Melting points of obtained compounds were determined by capillary method on PTP (M device. ІR-spectra of synthesized compounds were recorded on the Bruker Alpha device (company «Bruker» – Germany on 4000-400 sm-1 with using console ATR (direct insertion of compound. 1Н NMR-spectra were recorded on the Varian Mercury VX-200 device (company «Varian» – USA solvent – (DMSO-d6, internal standart – ТМС. Elemental analysis was made on Elementar Vario L cube device. Chromatoraphic studies were made on the plates Sorbfil-AFV-UV (company «Sobrpolimer» –Russia. Systhems for chromatography: «acetone-propanol-2» in ratio 2:3, «propanol-2-benzene» in ratio 10:1 and exersized in UV-light in wave 200-300 nm. Results and discussion We developed methodic of synthesis

  7. Co-pyrolysis of coal with hydrogen-rich gases. 1. Coal pyrolysis under coke-oven gas and synthesis gas

    Energy Technology Data Exchange (ETDEWEB)

    Liao, H.; Li, B.; Zhang, B. [Chinese Academy of Sciences, Taiyuan (China). State Key Lab. of Coal Conversion

    1998-06-01

    To improve the economics of the hydropyrolysis process, it has been suggested that cheaper hydrogen-rich gases (such as coke oven gas, synthesis gas) could be used instead of pure hydrogen. Pyrolysis of Chinese Xianfeng lignite was carried out with coke oven gas (COG) and synthesis gas (SG) as reactive gases at 0.1-5 MPa and at a final temperature up to 650{degree}C with a heating rate of 5-25{degree}C min{sup -1} in a 10 g fixed-bed reactor. The results indicate that it is possible to use COG and SG instead of pure hydrogen in hydropyrolysis, but that the experimental conditions must be adjusted to optimize the yields of the valuable chemicals. 14 refs., 3 figs., 6 tabs.

  8. Synthesis and enhanced neuroprotective activity of C60-based ebselen derivatives

    Energy Technology Data Exchange (ETDEWEB)

    Liu, X.-F. [Huazhong Univ. of Science and Technology, Dept. of Chemistry, Wuhan (China); Hubei Univ., Ministry of Education Key Lab. for the Synthesis and Application of Organic Functional Molecules, Wuhan (China); Guan, W.-C. [Huazhong Univ. of Science and Technology, Dept. of Chemistry, Wuhan (China)], E-mail: wcguan04@yahoo.com.cn; Ke, W.-S. [Hubei Univ., College of Life Science, Wuhan (China)

    2007-03-15

    A C{sub 60}-based ebselen derivative 4 was synthesized through the cycloaddition of C{sub 60} with the azide (3) containing the ebselen component. It was obtained in a four-step synthesis starting from 2-(chloroseleno)benzoyl chloride and 2-(2-aminoethoxy)ethanol in 53% yield (based on consumed C{sub 60}). Its structure was characterized by {sup 1}H NMR, {sup 13}C NMR, IR, UV, and FAB-MS. To verify that the C{sub 60}-based ebselen derivative 4 had enhanced antioxidative and neuroprotective activity, the C{sub 60} derivative 5 and the ebselen derivative 6 were selected to treat cortical neuronal cells using the same procedures as with the C{sub 60}-based ebselen derivative 4. The cellular viability of different derivative treatment groups was estimated by LDH leakage assay and MTT assay. At the same final concentration (30 {mu}mol/L), the results showed that the antioxidative and protective potencies of the C{sub 60}-based ebselen derivative 4 (MTT (OD) 0.340 {+-} 0.035, LDH release (UL{sup -1}) 4.80 {+-} 0.16) against H{sub 2}O{sub 2}-mediated neuronal injury have an advantage over those of C{sub 60} derivative 5 (MTT (OD) 0.297 {+-} 0.036, LDH release (UL{sup -1}) 5.37 {+-} 0.31) and ebselen derivative 6 (MTT (OD) 0.267 {+-} 0.027, LDH release (UL{sup -1}) 5.85 {+-} 0.26). Correspondingly, the GPX activity of 4 (1.62 U/{mu}mol) was higher than that of 5 (0.77 U/{mu}mol) and 6 (1.24 U/{mu}mol). These findings demonstrate that the incorporation of two components with similar biological activity (C{sub 60} component and ebselen component) may be a desirable way of obtaining a new and more biologically effective C{sub 60}-based compound. (author)

  9. Rice leaf hydrophobicity and gas films are conferred by a wax synthesis gene (LGF1) and contribute to flood tolerance

    DEFF Research Database (Denmark)

    Kurokawa, Yusuke; Nagai, Keisuke; Hung, Phung Danh

    2018-01-01

    Floods impede gas (O2and CO2) exchange between plants and the environment. A mechanism to enhance plant gas exchange under water comprises gas films on hydrophobic leaves, but the genetic regulation of this mechanism is unknown. We used a rice mutant (dripping wet leaf 7, drp7) which does...... not retain gas films on leaves, and its wild-type (Kinmaze), in gene discovery for this trait. Gene complementation was tested in transgenic lines. Functional properties of leaves as related to gas film retention and underwater photosynthesis were evaluated. Leaf Gas Film 1 (LGF1) was identified as the gene...... determining leaf gas films. LGF1 regulates C30 primary alcohol synthesis, which is necessary for abundant epicuticular wax platelets, leaf hydrophobicity and gas films on submerged leaves. This trait enhanced underwater photosynthesis 8.2-fold and contributes to submergence tolerance. Gene function...

  10. Synthesis of Netilmicin and Apramycin Derivatives for the Treatment of Multidrug-Resistant Infectious Diseases

    Science.gov (United States)

    Sonousi, Amr

    The ever-growing bacterial resistance to existing antibiotics is alarming to humanity. Many researchers decided to revisit aminoglycosides with renewed emphasis on chemical modification as they have long been used as highly potent antibiotics for treating severe bacterial infections. The bactericidal effect of aminoglycosides is mainly due to protein synthesis inhibition by binding to the A-site of the bacterial ribosomes. However, the high potency and the broad spectrum of aminoglycosides has been outweighed by their side effects, especially ototoxicity, and by the resistance of pathogens. The goal of this research was the modification of existing aminoglycosides to develop derivatives which are less toxic and that evade resistance. The chapters in the thesis discuss the chemical synthesis as well as the biological evaluation of the newly synthesized analogs. This study has focused on the modification of aminoglycosides netilmicin and apramycin. Chapter one introduces the MDR bacterial infection problem and its influence. Chapter one also introduces the aminoglycosides elaborating their history, classifications, and their mechanism of action. The resistance mechanisms against aminoglycosides and their adverse effects, as well as the ways to prevent them are briefly explained. Chapter two discusses modifications of netilmicin at the 4'-position conducted with a view to reducing the ototoxicity but not the antibiotic activity, as was previously done in the 4,5-series with paromomycin. The antibacterial activity and antiribosomal activity of the six netilmicin derivatives synthesized were determined. The 4'-position is more sensitive to modification in 4,6-series than in the 4,5-series to the extent that such modifications are ineffective. Chapter two also highlights the use of phenyl triazenes as selective protecting groups for secondary amines in the presence of primary amines. Several polyamine substrates were selectively protected as phenyl triazenes, and primary

  11. Synthesis of Fe Nanoparticles Functionalized with Oleic Acid Synthesized by Inert Gas Condensation

    Directory of Open Access Journals (Sweden)

    L. G. Silva

    2014-01-01

    Full Text Available In this work, we study the synthesis of monodispersed Fe nanoparticles (Fe-NPs in situ functionalized with oleic acid. The nanoparticles were self-assembled by inert gas condensation (IGC technique by using magnetron-sputtering process. Structural characterization of Fe-NPs was performed by transmission electron microscopy (TEM. Particle size control was carried out through the following parameters: (i condensation zone length, (ii magnetron power, and (iii gas flow (Ar and He. Typically the nanoparticles generated by IGC showed diameters which ranged from ~0.7 to 20 nm. Mass spectroscopy of Fe-NPs in the deposition system allowed the study of in situ nanoparticle formation, through a quadrupole mass filter (QMF that one can use together with a mass filter. When the deposition system works without quadrupole mass filter, the particle diameter distribution is around +/−20%. When the quadrupole is in line, then the distribution can be reduced to around +/−2%.

  12. Synthesis of l-cysteine derivatives containing stable sulfur isotopes and application of this synthesis to reactive sulfur metabolome.

    Science.gov (United States)

    Ono, Katsuhiko; Jung, Minkyung; Zhang, Tianli; Tsutsuki, Hiroyasu; Sezaki, Hiroshi; Ihara, Hideshi; Wei, Fan-Yan; Tomizawa, Kazuhito; Akaike, Takaaki; Sawa, Tomohiro

    2017-05-01

    Cysteine persulfide is an L-cysteine derivative having one additional sulfur atom bound to a cysteinyl thiol group, and it serves as a reactive sulfur species that regulates redox homeostasis in cells. Here, we describe a rapid and efficient method of synthesis of L-cysteine derivatives containing isotopic sulfur atoms and application of this method to a reactive sulfur metabolome. We used bacterial cysteine syntheses to incorporate isotopic sulfur atoms into the sulfhydryl moiety of L-cysteine. We cloned three cysteine synthases-CysE, CysK, and CysM-from the Gram-negative bacterium Salmonella enterica serovar Typhimurium LT2, and we generated their recombinant enzymes. We synthesized 34 S-labeled L-cysteine from O-acetyl-L-serine and 34 S-labeled sodium sulfide as substrates for the CysK or CysM reactions. Isotopic labeling of L-cysteine at both sulfur ( 34 S) and nitrogen ( 15 N) atoms was also achieved by performing enzyme reactions with 15 N-labeled L-serine, acetyl-CoA, and 34 S-labeled sodium sulfide in the presence of CysE and CysK. The present enzyme systems can be applied to syntheses of a series of L-cysteine derivatives including L-cystine, L-cystine persulfide, S-sulfo-L-cysteine, L-cysteine sulfonate, and L-selenocystine. We also prepared 34 S-labeled N-acetyl-L-cysteine (NAC) by incubating 34 S-labeled L-cysteine with acetyl coenzyme A in test tubes. Tandem mass spectrometric identification of low-molecular-weight thiols after monobromobimane derivatization revealed the endogenous occurrence of NAC in the cultured mammalian cells such as HeLa cells and J774.1 cells. Furthermore, we successfully demonstrated, by using 34 S-labeled NAC, metabolic conversion of NAC to glutathione and its persulfide, via intermediate formation of L-cysteine, in the cells. The approach using isotopic sulfur labeling combined with mass spectrometry may thus contribute to greater understanding of reactive sulfur metabolome and redox biology. Copyright © 2017 Elsevier Inc

  13. 4'-Methyl derivatives of 5-MOP and 5-MOA: synthesis, photoreactivity, and photobiological activity.

    Science.gov (United States)

    Gia, O; Anselmo, A; Conconi, M T; Antonello, C; Uriarte, E; Caffieri, S

    1996-10-25

    The synthesis and photobiological activity of four new 4'-methyl derivatives of 5-MOP (5-methoxypsoralen) and 5-MOA (5-methoxyangelicin), i.e., 4,4'-dimethyl-5-methoxypsoralen, 3,4'-dimethyl-5-methoxypsoralen, 4,4'-dimethyl-5-methoxyangelicin, and 3,4'-dimethyl-5-methoxyangelicin, are described. All these compounds photobind efficiently to DNA. The DNA-photobinding process was investigated using various nucleic acid structures such as double-helix DNA, bacterial DNA, and synthetic polydeoxyribonucleotides. Photoreaction experiments showed that, unlike 8-MOP (8-methoxypsoralen) and 5-MOP, both angular derivatives bind thymine and cytosine with the same efficiency. The principal nucleoside-psoralen monoadducts were isolated and characterized after enzymatic digestion or acid hydrolysis. Biological activity studies revealed a good correlation with the extent of covalent photoaddition. Moreover, the two angular derivatives and the 4,4'-dimethyl-5-methoxypsoralen were unable to induce skin erythema, in striking contrast with the reference drugs, 8-MOP and 5-MOP; only the 3,4'-dimethyl-5-methoxypsoralen caused erythema, although to a substantially lower extent than that induced by the two parent compounds.

  14. Synthesis, Immunosuppressive Properties, and Mechanism of Action of a New Isoxazole Derivative

    Directory of Open Access Journals (Sweden)

    Marcin Mączyński

    2018-06-01

    Full Text Available This work describes the synthesis of a new series of isoxazole derivatives, their immunosuppressive properties, and the mechanism of action of a representative compound. A new series of N′-substituted derivatives of 5-amino-N,3-dimethyl-1,2-oxazole-4-carbohydrazide (MM1–MM10 was synthesized in reaction of 5-amino-N,3-dimethyl-1,2-oxazole-4-carbohydrazide with relevant carbonyl compounds. The isoxazole derivatives were tested in several in vitro models using human cells. The compounds inhibited phytohemagglutinin A (PHA-induced proliferation of peripheral blood mononuclear cells (PBMCs to various degrees. The toxicity of the compounds with regard to a reference A549 cell line was also differential. 5-amino-N′-(2,4-dihydroxyphenylmethylidene-N,3-dimethyl-1,2-oxazole-4-carbohydrazide (MM3 compound was selected for further investigation because of its lack of toxicity and because it had the strongest antiproliferative activity. The compound was shown to inhibit lipopolysaccharide (LPS-induced tumor necrosis factor (TNF α production in human whole blood cell cultures. In the model of Jurkat cells, MM3 elicited strong increases in the expression of caspases, Fas, and NF-κB1, indicating that a proapoptotic action may account for its immunosuppressive action in the studied models.

  15. Semi-synthesis and NMR spectral assignments of flavonoid and chalcone derivatives.

    Science.gov (United States)

    Kumar, Rohitesh; Lu, Yuting; Elliott, Alysha G; Kavanagh, Angela M; Cooper, Matthew A; Davis, Rohan A

    2016-11-01

    Previous investigations of the aerial parts of the Australian plant Eremophila microtheca and Syzygium tierneyanum resulted in the isolation of the antimicrobial flavonoid jaceosidin (4) and 2',6'-dihydroxy-4'-methoxy-3',5'-dimethyl chalcone (7), respectively. In this current study, compounds 4 and 7 were derivatized by acetylation, pivaloylation, and methylation reactions. The final products, 5,7,4'-triacetoxy jaceosidin (10), 5,7,4'-tripivaloyloxy jaceosidin (11), 5,7,4'-trimethoxy jaceosidin (12), 2',6'-diacetoxy-4'-methoxy-3',5'-dimethyl chalcone (13), 2'-hydroxy-4'-methoxy-6'-pivaloyloxy-3',5'-dimethyl chalcone (14), and 2'-hydroxy-4',6'-dimethoxy-3',5'-dimethyl chalcone (15) were all fully characterized by NMR and MS. Derivatives 10 and 13 have been previously reported but were only partially characterized. This is the first reported synthesis of 11 and 14. The natural products and their derivatives were evaluated for their antibacterial and antifungal properties, and the natural product, jaceosidin (4) and the acetylated derivative, 5,7,4'-triacetoxy jaceosidin (10), showed modest antibacterial activity (32-128 µg/ml) against Staphylococcus aureus strains. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  16. Methodologies for predicting the part-load performance of aero-derivative gas turbines

    DEFF Research Database (Denmark)

    Haglind, Fredrik; Elmegaard, Brian

    2009-01-01

    Prediction of the part-load performance of gas turbines is advantageous in various applications. Sometimes reasonable part-load performance is sufficient, while in other cases complete agreement with the performance of an existing machine is desirable. This paper is aimed at providing some guidance...... on methodologies for predicting part-load performance of aero-derivative gas turbines. Two different design models – one simple and one more complex – are created. Subsequently, for each of these models, the part-load performance is predicted using component maps and turbine constants, respectively. Comparisons...... with manufacturer data are made. With respect to the design models, the simple model, featuring a compressor, combustor and turbines, results in equally good performance prediction in terms of thermal efficiency and exhaust temperature as does a more complex model. As for part-load predictions, the results suggest...

  17. Green synthesis of novel quinoline based imidazole derivatives and evaluation of their antimicrobial activity

    Directory of Open Access Journals (Sweden)

    N.C. Desai

    2014-12-01

    Full Text Available We have described the conventional and microwave method for the synthesis of N-(4-((2-chloroquinolin-3-ylmethylene-5-oxo-2-phenyl-4,5-dihydro-1H-imidazol-1-yl(arylamides 3a–l. It is observed that the solvent-free microwave thermolysis is a convenient, rapid, high-yielding, and environmental friendly protocol for the synthesis of quinoline based imidazole derivatives when compared with conventional reaction in a solution phase. Antimicrobial activity of the newly synthesized compounds is screened in vitro on the following microbial cultures: Escherichia coli (MTCC 443, Pseudomonas aeruginosa (MTCC 1688, Staphylococcus aureus (MTCC 96, Streptococcus pyogenes (MTCC 442, Candida albicans (MTCC 227, Aspergillus niger (MTCC 282, Aspergillus clavatus (MTCC 1323. All the synthesized bio-active molecules are tested for their in vitro antimicrobial activity by bioassay namely serial broth dilution. Among these compounds 3c, 3d, 3f, 3h and 3j show significant potency against different microbial strains. All the compounds have been characterized by IR, 1H NMR, 13C NMR and mass spectral data. On the basis of statistical analysis, it is observed that these compounds give significant co-relation.

  18. Synthesis of carbon-11 labeled celecoxib derivatives as new candidate PET radioligands for imaging of inflammation

    International Nuclear Information System (INIS)

    Gao Mingzhang; Wang Min; Miller, Kathy D.; Hutchins, Gary D.; Zheng Qihuang

    2009-01-01

    Cyclooxygenase (prostaglandin endoperoxide synthase or COX) enzyme represents a particularly attractive target in inflammation processes for the development of both therapeutic agents and imaging agents. This study was designed to develop new radioligands for imaging of inflammation using the biomedical imaging technique positron emission tomography (PET). Carbon-11 labeled celecoxib derivatives, [ 11 C]methyl 2-(4-(5-p-tolyl-3-(trifluoromethyl)-1H-pyrazol-1-yl)phenylsulfonamidooxy) acetate ([ 11 C]6e), [ 11 C]methyl 2-methyl-2-(4-(5-p-tolyl-3-(trifluoromethyl)-1H-pyrazol-1-yl) phenylsulfonamidooxy)propanoate ([ 11 C]6f), [ 11 C]methyl 2-(4-(5-(4-methoxyphenyl)-3-(trifluoromethyl)-1H-pyrazol-1-yl) phenylsulfonamidooxy)acetate ([ 11 C]6g), and [ 11 C]methyl 2-methyl-2-(4-(5-(4-methoxyphenyl)-3-(trifluoromethyl)-1H-pyrazol-1-yl) phenylsulfonamidooxy)propanoate ([ 11 C]6h), were prepared by O-[ 11 C]methylation of their corresponding precursors using [ 11 C]CH 3 OTf under basic condition and isolated by a simplified solid-phase extraction (SPE) method in 50-60% radiochemical yields based on [ 11 C]CO 2 and decay corrected to end of bombardment (EOB). The overall synthesis time from EOB was 15-20 min, the radiochemical purity was >99%, and the specific activity at end of synthesis (EOS) was 111-185 GBq/μmol.

  19. New Sorafenib Derivatives: Synthesis, Antiproliferative Activity Against Tumour Cell Lines and Antimetabolic Evaluation

    Directory of Open Access Journals (Sweden)

    Branka Zorc

    2012-01-01

    Full Text Available Sorafenib is a relatively new cytostatic drug approved for the treatment of renal cell and hepatocellular carcinoma. In this report we describe the synthesis of sorafenib derivatives 4a–e which differ from sorafenib in their amide part. A 4-step synthetic pathway includes preparation of 4-chloropyridine-2-carbonyl chloride hydrochloride (1, 4-chloro-pyridine-2-carboxamides 2a–e, 4-(4-aminophenoxy-pyridine-2-carboxamides 3a–e and the target compounds 4-[4-[[4-chloro-3-(trifluoromethylphenyl]carbamoylamino]-phenoxy]-pyridine-2-carboxamides 4a–e. All compounds were fully chemically characterized and evaluated for their cytostatic activity against a panel of carcinoma, lymphoma and leukemia tumour cell lines. In addition, their antimetabolic potential was investigated as well. The most prominent antiproliferative activity was obtained for compounds 4a–e (IC50 = 1-4.3 μmol·L−1. Their potency was comparable to the potency of sorafenib, or even better. The compounds inhibited DNA, RNA and protein synthesis to a similar extent and did not discriminate between tumour cell lines and primary fibroblasts in terms of their anti-proliferative activity.

  20. Microwave-assisted Synthesis of Benzimidazole Derivatives from Citronellal in Kaffir Lime (Citrus hystrix DC.) Oil

    Science.gov (United States)

    Sapri Ramadhan, Dwi; Warsito; Dhiaul Iftitah, Elvina

    2018-01-01

    Benzimidazoles are an important group of heterocyclic aromatic organic compound in the field of medicinal chemistry. It plays a very important role in pharmacological activity such as, analgesic, antiinflammatory, antibacterial, anti ungal, anti iral, antithelmenthic, anti convulsant, antihypertensive, and antiulcer. The synthesis of benzimidazole derivative under microwave irradiation of citronellal as raw material which is extracted from Citrus hystrix DC. (kaffir lime) leaves. The reaction using methanol and dichloromethane as solvent with variation of reaction time at 30, 40, 50, 60, and 70 minutes and mole ratio of citronellal to 1,2-phenylenediamine, 1:1, 1:1.5, and 1:2, respectively. Synthesis products was characterized by FT-IR and GC-MS. The optimum reaction time was obtained at 60 minutes in the present of dichloromethane and 1:2 mole ratio of citronellal to 1,2-phenylenediamine. The yield of the product is 42.19%. Structure of the synthesized compound were assigned on spectrum bands for C=N str at 1661 cm-1, C-N str at 1271 cm-1, C=C str of benzene ring at 1622 and 1456 cm-1 and C=C str of alkene at 1379 cm-1. GC-MS analysis showed single peak with retention time of 15.339 minute and m/z 242.

  1. GlidArc-assisted production of synthesis gas from LPG (Propane)

    International Nuclear Information System (INIS)

    Czernichowski, A.; Czernichowski, P.; Czernichowski, M.

    2003-01-01

    Small and medium size reformers that run on widely available Liquefied Petroleum Gas (LPG, containing mostly the propane) can provide Synthesis Gas (or Hydrogen extracted from it) to some Fuel Cell powered cars, boats, homes, farms etc. reducing therefore costs of the pure Hydrogen distribution. We contribute to such idea realization through our simply, plasma-assisted reformer avoiding a need of poison resistant catalysts or prior LPG desulfurizer. In fact, any level of sulphur in LPG is accepted for our non-catalytic reformer based on high-voltage discharges (called GlidArc). The discharges catalytically assist the exothermic partial oxidation process. Electric power assistance is less than 2% of the Lower Heating Value (LHV) of produced SynGas. Recycling such a small portion of the energy is therefore an acceptable compromise. The unique oxidant source is air. This contribution presents our expanded tests with commercial LPG in a 1-L reactor working at atmospheric pressure. At a 0.1 kW electric power assistance we produce a Nitrogen-diluted SynGas containing up to 45% of H 2 +CO at the output flow rate corresponding up to 2.7 m 3 (n)/h of pure H 2 +CO mixture that is equivalent to LHV output power of 8.6 kW. The LPG is totally reformed at more than 70% energetic efficiency and at the total absence of soot. (author)

  2. Synthesis and application of graphene–silver nanowires composite for ammonia gas sensing

    International Nuclear Information System (INIS)

    Tran, Quang Trung; Huynh, Tran My Hoa; Tong, Duc Tai; Tran, Van Tam; Nguyen, Nang Dinh

    2013-01-01

    Graphene, consisting of a single carbon layer in a two-dimensional (2D) lattice, has been a promising material for application to nanoelectrical devices in recent years. In this study we report the development of a useful ammonia (NH 3 ) gas sensor based on graphene–silver nanowires ‘composite’ with planar electrode structure. The basic strategy involves three steps: (i) preparation of graphene oxide (GO) by modified Hummers method; (ii) synthesis of silver nanowires by polyol method; and (iii) preparation of graphene and silver nanowires on two electrodes using spin and spray-coating of precursor solutions, respectively. Exposure of this sensor to NH 3 induces a reversible resistance change at room temperature that is as large as ΔR/R 0 ∼ 28% and this sensitivity is eight times larger than the sensitivity of the ‘intrinsic’ graphene based NH 3 gas sensor (ΔR/R 0 ∼ 3,5%). Their responses and the recovery times go down to ∼200 and ∼60 s, respectively. Because graphene synthesized by chemical methods has many defects and small sheets, it cannot be perfectly used for gas sensor or for nanoelectrical devices. The silver nanowires are applied to play the role of small bridges connecting many graphene islands together to improve electrical properties of graphene/silver nanowires composite and result in higher NH 3 gas sensitivity. (paper)

  3. Synthetic transformations of isoquinoline alkaloids. Synthesis of dihydrothebaine-hydroquinone derivatives

    International Nuclear Information System (INIS)

    Bauman, V.T.; Shul'ts, Eh. Eh.; Shakirov, M.M.; Tolstikov, G.A.

    2007-01-01

    Synthesis of new 6,14-endo-ethenodihydrothebaine-hydroquinone derivatives is carried through the introduction of iodine in molecule of the compound by means of iodine chloride or iodine in the presence of cerium-ammonium nitrate. 1-Iodine-5,14-endo-etheno-7,8-(1-acetoxy-4-hydroxybenzo)dihydrothebaine (yield 57%), 1-iodine-6,14-endo-etheno-7,8-(1,4-hydroquinono)dihydrothebaine (yield 13%) and 1-iodine-5'-chlorine-6,14-endo-etheno-7,8-(1,4-hydroquinono)dihydrothebaine (yield 11%) are separated as products of the reaction. Structure, molecular mass and element composition of iodination products were established on the basis of analysis of NMR spectra and mass spectroscopy, course of the reaction was controlled by TLC method [ru

  4. Hybrid Compounds Strategy in the Synthesis of Oleanolic Acid Skeleton-NSAID Derivatives

    Directory of Open Access Journals (Sweden)

    Anna Pawełczyk

    2016-04-01

    Full Text Available The current study focuses on the synthesis of several hybrid individuals combining a natural oleanolic acid skeleton and synthetic nonsteroidal anti-inflammatory drug moieties (NSAIDs. It studied structural modifications of the oleanolic acid structure by use of the direct reactivity of hydroxyl or hydroxyimino groups at position C-3 of the triterpenoid skeleton with the carboxylic function of anti-inflammatory drugs leading to new perspective compounds with high potential pharmacological activities. Novel ester- and iminoester-type derivatives of oleanolic unit with the different NSAIDs, such as ibuprofen, aspirin, naproxen, and ketoprofen, were obtained and characterized. Moreover, preliminary research of compounds obtaining structure stability under acidic conditions was examined and the PASS method of prediction of activity spectra for substances was used to estimate the potential biological activity of these compounds.

  5. Synthesis and in vivo antimalarial activity of novel naphthoquine derivatives with linear/cyclic structured pendants.

    Science.gov (United States)

    Tang, Ling; Bei, Zhuchun; Song, Yabin; Xu, Likun; Wang, Hong; Zhang, Dongna; Dou, Yuanyuan; Lv, Kai; Wang, Hongquan

    2017-07-01

    Naphthoquine (NQ) was discovered by our institute as an antimalarial candidate in 1980s, and currently employed as an artemisinin-based combination therapy partner drug. Resistance to NQ was found in mouse model in laboratory, and might emerge in future as widely used. We herein report the design and synthesis of NQ derivatives by replacing t-butyl moiety with linear/cyclic structured pendants. All the target compounds 6a-l and intermediates 5a-h were tested for their in vivo antimalarial activity against Plasmodium berghei K173 strain in mice. Compounds 6a and 6j were found to have a comparable or slightly more potent activity (the 50% effective dose [ED 50 ], which is required to decrease parasitemia by 50%: 0.38-0.43 mg/kg) than NQ (ED 50 : 0.48 mg/kg). The newly designed compounds 6a and 6j might be promising antimalarial candidates for further research.

  6. Studies on the Synthesis of Etodolac Derivatives as Potential Anti-inflammatory Agents

    Energy Technology Data Exchange (ETDEWEB)

    Cho, H.; Chung, Y.S. [Department of Chemistry, Chungbuk Natiojal University (Korea); Jang, H.D. [Department of Chemical Engineering, Seoul National Polytechnic University (Korea); Ryu, S.R. [Department of Chemical Engineering, Dae Bul University (Korea)

    1999-02-01

    For the synthesis of new anti-inflammatory agents as indol derivatives, we have synthesized a-benzoyl-1-ethyl-1,3,4,9-tetrahydro-8-ethyl-9-(N-benzoyl)pyrano[3,4-b]indole-= 1-acetic acid methyl ester. It was a new method for a-substituted etodolac carboxylic acid. The synthetic process was composed of four steps, and 7-ethylindole and oxalyl chloride were used as starting materials. The third step, cyclization was carried out by addition of borontrifluoride diethyl etherate in 66% yield. The step of reduction and cyclization were simplified successfully. The final product, a-benzoyl-1-ethyl-1,3,4,9-tetrahydropyrano[3,4-b]indole-1-acetate (etodollic acid methyl ester) and benzoyl chloride. 14 refs., 3 figs.

  7. Synthesis and Structural Characterization of 1- and 2-Substituted Indazoles: Ester and Carboxylic Acid Derivatives

    Directory of Open Access Journals (Sweden)

    Isabel Bento

    2006-11-01

    Full Text Available A series of indazoles substituted at the N-1 and N-2 positions with ester-containing side chains -(CH2nCO2R of different lengths (n = 0-6, 9, 10 are described.Nucleophilic substitution reactions on halo esters (X(CH2nCO2R by 1H-indazole inalkaline solution lead to mixtures of N-1 and N-2 isomers, in which the N-1 isomerpredominates. Basic hydrolysis of the ester derivatives allowed the synthesis of thecorresponding indazole carboxylic acids. All compounds were fully characterised bymultinuclear NMR and IR spectroscopies, MS spectrometry and elemental analysis; theNMR spectroscopic data were used for structural assignment of the N-1 and N-2 isomers.The molecular structure of indazol-2-yl-acetic acid (5b was determined by X-raydiffraction, which shows a supramolecular architecture involving O2-H...N1intermolecular hydrogen bonds.

  8. Silica-Supported Polyphosphoric Acid in the Synthesis of 4-Substituted Tetrahydroisoquinoline Derivatives

    Directory of Open Access Journals (Sweden)

    Iliyan Ivanov

    2013-02-01

    Full Text Available We report herein an application of an α-amidoalkylation reaction, as an alternative efficient synthesis of 4-aryl- and 4-methyl-1,2,3,4-tetrahydroisoquinoline derivatives. The amides required for this purpose would result from reaction of aminoacetaldehyde dimethylacetal with different substituted benzenes in polyphosphoric acid, followed by acylation of the obtained amines with different acid chlorides or sulfochlorides. We compared the cyclisation step using conventional (milieu of acetic-trifluoracetic acid = 4:1 and solid supported reagents (SiO2/PPA, as recovered, regenerated and reused without loss of its activity catalyst. We found that in comparison to conventional methods, the yields of the reaction are greater and the reaction time is shorter.

  9. Analytical Solution for Fractional Derivative Gas-Flow Equation in Porous Media

    KAUST Repository

    El-Amin, Mohamed; Radwan, Ahmed G.; Sun, Shuyu

    2017-01-01

    In this paper, we introduce an analytical solution of the fractional derivative gas transport equation using the power-series technique. We present a new universal transform, namely, generalized Boltzmann change of variable which depends on the fractional order, time and space. This universal transform is employed to transfer the partial differential equation into an ordinary differential equation. Moreover, the convergence of the solution has been investigated and found that solutions are unconditionally converged. Results are introduced and discussed for the universal variable and other physical parameters such as porosity and permeability of the reservoir; time and space.

  10. Analytical Solution for Fractional Derivative Gas-Flow Equation in Porous Media

    KAUST Repository

    El-Amin, Mohamed

    2017-07-06

    In this paper, we introduce an analytical solution of the fractional derivative gas transport equation using the power-series technique. We present a new universal transform, namely, generalized Boltzmann change of variable which depends on the fractional order, time and space. This universal transform is employed to transfer the partial differential equation into an ordinary differential equation. Moreover, the convergence of the solution has been investigated and found that solutions are unconditionally converged. Results are introduced and discussed for the universal variable and other physical parameters such as porosity and permeability of the reservoir; time and space.

  11. Synthesis of the Galactosyl Derivative of Gluconic Acid With the Transglycosylation Activity of β-Galactosidase

    Directory of Open Access Journals (Sweden)

    Aleksandra Wojciechowska

    2017-01-01

    Full Text Available Bionic acids are bioactive compounds demonstrating numerous interesting properties. They are widely produced by chemical or enzymatic oxidation of disaccharides. This paper focuses on the galactosyl derivative of gluconic acid as a result of a new method of bionic acid synthesis which utilises the transglycosylation properties of β-galactosidase and introduces lactose as a substrate. Products obtained in such a process are characterised by different structures (and, potentially, properties than those resulting from traditional oxidation of disaccharides. The aim of this study is to determine the effect of selected parameters (concentration and ratio of substrates, dose of the enzyme, time, pH, presence of salts on the course of the reaction carried out with the enzymatic preparation Lactozym, containing β-galactosidase from Kluyveromyces lactis. Research has shown that increased dry matter content in the baseline solution (up to 50 %, by mass per volume and an addition of NaCl contribute to higher yield. On the other hand, reduced content of the derivative is a result of increased pH from 7.0 to 9.0 and an addition of magnesium and manganese salts. Moreover, exceeding the β-galactosidase dose over approx. 35 000 U per 100 g of lactose also leads to reduced yield of the process. The most favourable molar ratio of sodium gluconate to lactose is 2.225:0.675. Depending on the conditions of the synthesis, the product concentration ranged between 17.3 and 118.3 g/L of the reaction mixture, which corresponded to the mass fraction of 6.64–23.7 % of dry matter. The data obtained as a result of the present study may be useful for designing an industrial process.

  12. Synthesis, antifungal activity, and QSAR studies of 1,6-dihydropyrimidine derivatives

    Directory of Open Access Journals (Sweden)

    Chirag Rami

    2013-01-01

    Full Text Available Introduction: A practical synthesis of pyrimidinone would be very helpful for chemists because pyrimidinone is found in many bioactive natural products and exhibits a wide range of biological properties. The biological significance of pyrimidine derivatives has led us to the synthesis of substituted pyrimidine. Materials and Methods: With the aim of developing potential antimicrobials, new series of 5-cyano-6-oxo-1,6-dihydro-pyrimidine derivatives namely 2-(5-cyano-6-oxo-4-substituted (aryl-1,6-dihydropyrimidin-2-ylthio-N-substituted (phenyl acetamide (C1-C41 were synthesized and characterized by Fourier transform infrared spectroscopy (FTIR, mass analysis, and proton nuclear magnetic resonance ( 1 H NMR. All the compounds were screened for their antifungal activity against Candida albicans (MTCC, 227. Results and Discussion: Quantitative structure activity relationship (QSAR studies of a series of 1,6-dihydro-pyrimidine were carried out to study various structural requirements for fungal inhibition. Various lipophilic, electronic, geometric, and spatial descriptors were correlated with antifungal activity using genetic function approximation. Developed models were found predictive as indicated by their square of predictive regression values (r 2pred and their internal and external cross-validation. Study reveals that CHI_3_C, Molecular_SurfaceArea, and Jurs_DPSA_1 contributed significantly to the activity along with some electronic, geometric, and quantum mechanical descriptors. Conclusion: A careful analysis of the antifungal activity data of synthesized compounds revealed that electron withdrawing substitution on N-phenyl acetamide ring of 1,6-dihydropyrimidine moiety possess good activity.

  13. Synthesis of trideuterated O-alkyl platelet activating factor and lyso derivatives

    International Nuclear Information System (INIS)

    Prakash, C.; Saleh, S.; Taber, D.F.; Blair, I.A.

    1989-01-01

    Racemic heavy isotope analogs of 1-O-alkyl-sn-glycero-3-phosphocholine (lysoPAF) and 1-O-alkyl-2-O-acetyl-sn-glycero-3-phosphocholine (PAF) were prepared for use as internal standards to facilitate quantitative studies based on mass spectrometry. Starting from pentadecane-1,15-diol and rac-glycerol-1,2-acetonide, a convergent synthesis of 1-O-[16'-2H3]hexadecyl and 1-O-[18'-2H3]octadecyl rac-glycero-3-phosphocholine and their acetyl derivatives is described. Three deuterium atoms were introduced at the terminal position of the 1-O-alkyl group by displacement of the p-toluensulfonyl group from 1-O-alkyl-15'-p-toluensulfonate and 1-O-alkyl-17'-p-toluensulfonate with [2H3]-methylmagnesium iodide. The 1-O-alkyl-17'-p-toluensulfonate was obtained by reaction of the 1-O-alkyl-15'-p-toluensulfonate with allylmagnesium bromide, followed by reductive ozonolysis and treatment with p-toluene-sulfonyl chloride. The hydroxyl group at C-2 was protected by a benzyl group and removed at a late stage in the synthesis. This provided the corresponding lyso-derivatives or allowed preparation of racemic PAF by subsequent acetylation of the free hydroxy group. The phosphocholine moiety was introduced at glycerol C-3 by reaction with bromoethyldichlorophosphate and trimethylamine. The synthetic compounds were analyzed by FAB/MS and GC/NICIMS. They were shown to contain less than 0.6% protium impurity

  14. Preliminary study of synthesis gas production from water electrolysis, using the ELECTROFUEL® concept

    International Nuclear Information System (INIS)

    Guerra, L.; Gomes, J.; Puna, J.; Rodrigues, J.

    2015-01-01

    This paper describes preliminary work on the generation of synthesis gas from water electrolysis using graphite electrodes without the separation of the generated gases. This is an innovative process, that has no similar work been done earlier. Preliminary tests allowed to establish correlations between the applied current to the electrolyser and flow rate and composition of the generated syngas, as well as a characterisation of generated carbon nanoparticles. The obtained syngas can further be used to produce synthetic liquid fuels, for example, methane, methanol or DME (dimethyl ether) in a catalytic reactor, in further stages of a present ongoing project, using the ELECTROFUEL ® concept. The main competitive advantage of this project lies in the built-in of an innovative technology product, from RE (renewable energy) power in remote locations, for example, islands, villages in mountains as an alternative for energy storage for mobility constraints. - Highlights: • Generation of synthesis gas from water electrolysis without separation of gases. • Obtained syngas: 7.7% CO; 10.3% O 2 and 2.0% CO 2 . • Syngas can further be used to produce synthetic liquid fuels

  15. Single-step gas phase synthesis of stable iron aluminide nanoparticles with soft magnetic properties

    Energy Technology Data Exchange (ETDEWEB)

    Vernieres, Jerome, E-mail: Jerome.vernieres@oist.jp; Benelmekki, Maria; Kim, Jeong-Hwan; Grammatikopoulos, Panagiotis; Diaz, Rosa E. [Nanoparticles by Design Unit, Okinawa Institute of Science and Technology (OIST) Graduate University, 1919-1 Tancha, Onna Son, Okinawa 904-0495 (Japan); Bobo, Jean-François [Centre d’Elaboration de Materiaux et d’Etudes Structurales (CEMES), 29 rue Jeanne Marvig, 31055 Toulouse Cedex 4 (France); Sowwan, Mukhles, E-mail: Mukhles@oist.jp [Nanoparticles by Design Unit, Okinawa Institute of Science and Technology (OIST) Graduate University, 1919-1 Tancha, Onna Son, Okinawa 904-0495 (Japan); Nanotechnology Research Laboratory, Al-Quds University, P.O. Box 51000, East Jerusalem, Palestine (Country Unknown)

    2014-11-01

    Soft magnetic alloys at the nanoscale level have long generated a vivid interest as candidate materials for technological and biomedical purposes. Consequently, controlling the structure of bimetallic nanoparticles in order to optimize their magnetic properties, such as high magnetization and low coercivity, can significantly boost their potential for related applications. However, traditional synthesis methods stumble upon the long standing challenge of developing true nanoalloys with effective control over morphology and stability against oxidation. Herein, we report on a single-step approach to the gas phase synthesis of soft magnetic bimetallic iron aluminide nanoparticles, using a versatile co-sputter inert gas condensation technique. This method allowed for precise morphological control of the particles; they consisted of an alloy iron aluminide crystalline core (DO{sub 3} phase) and an alumina shell, which reduced inter-particle interactions and also prevented further oxidation and segregation of the bimetallic core. Remarkably, the as-deposited alloy nanoparticles show interesting soft magnetic properties, in that they combine a high saturation magnetization (170 emu/g) and low coercivity (less than 20 Oe) at room temperature. Additional functionality is tenable by modifying the surface of the particles with a polymer, to ensure their good colloidal dispersion in aqueous environments.

  16. Synthesis, physical-chemical and biological properties of 7-benzyl-3-methyl-8-thioxanthine derivatives

    Directory of Open Access Journals (Sweden)

    D. H. Ivanchenko

    2017-12-01

    Full Text Available Introduction . Interest to the problem of creating new effective antimicrobial agents among xanthine derivatives does not decrease. Primarily, this is due to the increasing of microbial resistance to conventional antimicrobial agents and the emergence of their new strains. In recent years interest to the therapeutic use of antioxidants in the treatment of diseases associated with oxidative stress has increased. The aim of this work is to elaborate simple laboratory methods of 7-benzyl-3-methyl-8-thioxanthine derivatives synthesis, unspecified in scientific papers earlier, and to study their physical, chemical and biological properties. Materials and methods. The melting point has been determined with the help of an open capillary method with PTP-M device. Elemental analysis has been performed with the help of the instrument Elementar Vario L cube, NMR-spectra have been taken on a spectrometer Bruker SF-400 (operating frequency of 400 MHz, solvent DMSO, internal standard – TMS. Study of antimicrobial and antifungal activity of synthesized compounds has been performed by two-fold serial dilution method. Standard test strains have been used for the study: Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 25923, Pseudomonas aeruginosa ATCC 27853, Candida albicans ATCC 885-653. Dimethylsulfoxide was used as the solvent of the compounds. Results. Under short-time heating up of the initial 7-benzyl-3-methyl-8-thioxanthine with alkyl, alkenyl, benzyl halides or heteroalkylchlorides in a water-propanol-2 mixture in the presence of an equimolar amount of sodium hydroxide leads to the formation of 8-S-substituted of 7-benzyl-3-methylxanthines. Structure of synthesized compounds was definitely proved by NMR-spectroscopy. We conducted primary screening research of antimicrobial activity of 7-benzyl-3-methyl-8-thioxanthine derivatives, which revealed moderate and weak activity in concentrations 50-100 mcg/ml. Most of the obtained compounds showed a

  17. Synthesis of New Imidazolidin-2,4-dione and 2-Thioxoimidazolidin-4-ones via C-Phenylglycine Derivatives

    Directory of Open Access Journals (Sweden)

    José Alixandre de Sousa Luis

    2009-12-01

    Full Text Available Hydantoins and their derivatives constitute a group of pharmaceutical compounds with anticonvulsant and antiarrhythmic properties, and are also used against diabetes. N-3 and C-5 substituted imidazolidines are examples of such products. As such, we have developed a synthesis of 2,4-dione and 2-thioxo-4-one imidazolidinic derivatives by reaction of amino acids with C-phenylglycine, phenyl isocyanate and phenyl isothiocyanate. Four amino-derivatives IG(1-4 and eight imidazolidinic derivatives, IM(1-8, were obtained in yields of 70–74%. The mass, infrared, 1H and 13C-NMR spectra of representative products are discussed.

  18. Synthesis and solar-cell applications of novel furanyl-substituted anthracene derivatives

    Science.gov (United States)

    Kivrak, Arif; Er, Ömer Faruk; Kivrak, Hilal; Topal, Yasemin; Kuş, Mahmut; Çamlısoy, Yesim

    2017-11-01

    At present, novel furanyl-substituted anthracene derivatives; namely 9,10-di(furan-2-yl)anthracene (DFA), 5,5‧-(anthracene-9,10-diyl)bis(furan-2-carbaldehyde) (DAFA) and 2,2‧-((5,5‧-(anthracene-9,10-diyl)bis(furan-5,2-diyl))bis(methanylylidene))dimalononitrile (DCNFA) were designed and synthesized successfully by employing Stille Cross-Coupling, Vilsmeier-Haack and Knoevenagel condensation reactions, respectively. This methodology provides a practical new route for the synthesis of furanyl-substituted anthracene derivatives bearing strong electron-withdrawing groups. The electrochemical and electro-optical properties of these novel furanyl-substituted anthracene derivatives were also examined with strong acceptor-π-donor-π-acceptor interactions. Furthermore, Highest occupied molecular orbital (HOMO), Lowest Unoccupied molecular orbital (LUMO), and band gap (Eg) values were investigated by using spectroscopic methods. Electrochemical and electro-optical properties were calculated and compared to DFA, DAFA and DCNFA. Eg was found as 2.85, 2.71, and 2.33 eV, respectively. Consequently, Organic Solar Cells (OSC) were fabricated to investigate their solar cell performances. The strong electron withdrawing groups did not increase the solar cell performance of furanyl-anthracenes. Surprisingly, DFA was found to exhibit the best OSCs performance (Efficiency = 3.36). As a result, one could note that these novel furanyl-substituted anthracene derivatives are good candidate for the applications of the OSCs. Our results might help in the development of new materials with important electrochemical functions by giving the advantage of designing and further derivatization of new generation small organic molecules for photovoltaic device applications.

  19. Power to Fuels: Dynamic Modeling of a Slurry Bubble Column Reactor in Lab-Scale for Fischer Tropsch Synthesis under Variable Load of Synthesis Gas

    Directory of Open Access Journals (Sweden)

    Siavash Seyednejadian

    2018-03-01

    Full Text Available This research developed a comprehensive computer model for a lab-scale Slurry Bubble Column Reactor (SBCR (0.1 m Dt and 2.5 m height for Fischer–Tropsch (FT synthesis under flexible operation of synthesis gas load flow rates. The variable loads of synthesis gas are set at 3.5, 5, 7.5 m3/h based on laboratory adjustments at three different operating temperatures (483, 493 and 503 K. A set of Partial Differential Equations (PDEs in the form of mass transfer and chemical reaction are successfully coupled to predict the behavior of all the FT components in two phases (gas and liquid over the reactor bed. In the gas phase, a single-bubble-class-diameter (SBCD is adopted and the reduction of superficial gas velocity through the reactor length is incorporated into the model by the overall mass balance. Anderson Schulz Flory distribution is employed for reaction kinetics. The modeling results are in good agreement with experimental data. The results of dynamic modeling show that the steady state condition is attained within 10 min from start-up. Furthermore, they show that step-wise syngas flow rate does not have a detrimental influence on FT product selectivity and the dynamic modeling of the slurry reactor responds quite well to the load change conditions.

  20. Olefin cross metathesis based de novo synthesis of a partially protected L-amicetose and a fully protected L-cinerulose derivative

    Directory of Open Access Journals (Sweden)

    Bernd Schmidt

    2014-05-01

    Full Text Available Cross metathesis of a lactate derived allylic alcohol and acrolein is the entry point to a de novo synthesis of 4-benzoate protected L-amicetose and a cinerulose derivative protected at C5 and C1.

  1. Catalytic and Noncatalytic Conversion of Methane to Olefins and Synthesis Gas in an AC Parallel Plate Discharge Reactor

    Directory of Open Access Journals (Sweden)

    Mohammad Ali Khodagholi

    2013-01-01

    Full Text Available Direct conversion of methane to ethylene, acetylene, and synthesis gas at ambient pressure and temperature in a parallel plate discharge reactor was investigated. The experiments were carried out using a quartz reactor of outer diameter of 9 millimeter and a driving force of ac current of 50 Hz. The input power to the reactor to establish a stable gas discharge varied from 9.6 to maximum 15.3 watts (w. The effects of ZSM5, Fe–ZSM5, and Ni–ZSM5 catalysts combined with corona discharge for conversion of methane to more valued products have been addressed. It was found that in presence or absence of a catalyst in gas discharge reactor, the rate of methane and oxygen conversion increased upon higher input power supplied to the reactor. The effect of Fe–ZSM5 catalyst combined with gas discharge plasma yields C2 hydrocarbons up to 21.9%, which is the highest productions of C2 hydrocarbons in this work. The effect of combined Ni–ZSM5 and gas discharge plasma was mainly production of synthesis gas. The advantage of introducing ZSM5 to the plasma zone was increase in synthesis gas and acetylene production. The highest energy efficiency was 0.22 mmol/kJ, which belongs to lower rate of energy injection to the reactor.

  2. Efficient sonochemical synthesis of alkyl 4-aryl-6-chloro-5-formyl-2-methyl-1,4-dihydropyridine-3-carboxylate derivatives.

    Science.gov (United States)

    Ruiz, Enrique; Rodríguez, Hortensia; Coro, Julieta; Niebla, Vladimir; Rodríguez, Alfredo; Martínez-Alvarez, Roberto; de Armas, Hector Novoa; Suárez, Margarita; Martín, Nazario

    2012-03-01

    A facile, efficient and environment-friendly protocol for the synthesis of 6-chloro-5-formyl-1,4-dihydropyridine derivatives has been developed by the convenient ultrasound-mediated reaction of 2(1H)pyridone derivatives with the Vilsmeier-Haack reagent. This method provides several advantages over current reaction methodologies including a simpler work-up procedure, shorter reaction times and higher yields. Copyright © 2011. Published by Elsevier B.V.

  3. Modeling of a three-phase reactor for bitumen-derived gas oil hydrotreating

    Energy Technology Data Exchange (ETDEWEB)

    Chacon, R.; Canale, A.; Bouza, A. [Departamento de Termodinamica y Fenomenos de Transporte. Universidad Simon Bolivar, Caracas (Venezuela, Bolivarian Republic of); Sanchez, Y. [Departamento de Procesos y Sistemas. Universidad Simon Bolivar (Venezuela, Bolivarian Republic of)

    2012-01-15

    A three-phase reactor model for describing the hydrotreating reactions of bitumen-derived gas oil was developed. The model incorporates the mass-transfer resistance at the gas-liquid and liquid-solid interfaces and a kinetic rate expression based on a Langmuir-Hinshelwood-type model. We derived three correlations for determining the solubility of hydrogen (H{sub 2}), hydrogen sulfide (H{sub 2}S) and ammonia (NH{sub 3}) in hydrocarbon mixtures and the calculation of the catalyst effectiveness factor was included. Experimental data taken from the literature were used to determine the kinetic parameters (stoichiometric coefficients, reaction orders, reaction rate and adsorption constants for hydrodesulfuration (HDS) and hydrodenitrogenation (HDN)) and to validate the model under various operating conditions. Finally, we studied the effect of operating conditions such as pressure, temperature, LHSV, H{sub 2}/feed ratio and the inhibiting effect of H{sub 2}S on HDS and NH{sub 3} on HDN. (author)

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

    Directory of Open Access Journals (Sweden)

    Zhen-Yu Yang

    2018-06-01

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

  5. Synthesis, characterization and serum albumin binding studies of vitamin K3 derivatives.

    Science.gov (United States)

    Suganthi, Murugesan; Elango, Kuppanagounder P

    2017-01-01

    Synthesis, characterization and bovine serum albumin (BSA) binding properties of three derivatives of vitamin K3 have been described. Results of UV-Vis and fluorescence spectra indicate complexation between BSA and the ligands with conformational changes in protein, which is strongly supported by synchronous and three dimensional fluorescence studies. Addition of the ligands quenches the fluorescence of BSA which is accompanied by reduction in quantum yield (Ф) from 0.1010 to 0.0775-0.0986 range. Thermodynamic investigations reveal that hydrophobic interaction is the major binding force in the spontaneous binding of these ligands with BSA. The binding constants obtained depend on the substituent present in the quinone ring, which correlates linearly with the Taft's field substituent constant (σ F ). The results show that compound with strong electron withdrawing nitro-group forms relatively stronger complex with BSA than amino and thioglycolate substituted ones. Circular dichroism studies show that the α-helical content of the protein, upon complexation with the ligands, decreases in the case of amino and nitro substituted vitamin K3 while increases in thioglycolate substituted compound. Molecular docking studies indicated that the vitamin K3 derivatives are surrounded by hydrophobic residues of the BSA molecule, which is in good agreement with the results of fluorescence spectral and thermodynamic studies. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Synthesis and Application of Phenyl Nitrone Derivatives as Acidic and Microbial Corrosion Inhibitors

    Directory of Open Access Journals (Sweden)

    Shijun Chen

    2015-01-01

    Full Text Available Nitrone has drawn great attention due to its wide applications as a 1,3-dipole in heterocyclic compounds synthesis and the bioactivities. With the special structure, nitrone can also be used as ligand in inorganic chemistry. Based on the current research, the nitrones are anticipated to be effective inhibitors against acidic and microbial corrosion. The aim of this work is to investigate the inhibitory action of nitrones. In this work, a series of phenyl nitrone derivatives (PN was synthesized and used as acidic and microbial corrosion inhibitors. The results indicate that several compounds show moderate to high inhibition efficiency (IE in 3% HCl. Accompanied with HMTA or BOZ, the IEs greatly increase, and the highest efficiency of 98.5% was obtained by using PN4 + BOZ. Investigation of the antibacterial activity against oilfield microorganism shows that the nitrone derivatives can inhibit SRB, IB, and TGB with moderate to high efficiency under 1,000 mg/L, which makes them potential to be used as bifunctional oilfield chemicals.

  7. Synthesis and Electrochemical Study of a TCAA Derivative – A potential bipolar redox-active material

    International Nuclear Information System (INIS)

    Hagemann, Tino; Winsberg, Jan; Wild, Andreas; Schubert, Ulrich S.

    2017-01-01

    The 2,3,7,8-tetracyano-1,4,5,6,9,10-hexazaanthracene (TCAA) derivatives represent an interesting substance class for future research on organic electronic devices, such as solar cells, organic batteries or redox-flow batteries (RFBs). Because of their multivalent redox behavior they are potentially “bipolar”, usable both as cathode and anode activ charge-storage materials. Furthermore, they show a strong absorption and fluorescence behavior both in solution and solid state, rendering them a promising emitter for electroluminescence devices, like lamps or displays. In order to evaluate a TCAA for electrochemical applications the derivative 2,3,7,8-tetracyano-5,10-diphenyl-5,10-dihydrodipyrazino[2,3-b:2′,3′-e] pyrazine (2) was synthesized in two straightforward synthesis steps. The electrochemical behavior of 2 was initially determined by density functional theory (DFT) calculation and afterwards investigated via rotating disc electrode (RDE), UV–vis–NIR spectroelectrochemical as well as cyclic voltammetry (CV) measurements. It features a quasi-reversible oxidation and re-reduction at E ½ = 1.42 V vs. Fc + /Fc with a peak split of 96 mV and a quasi-reversible reduction and re-oxidation at E ½ = −1.49 V vs. Fc + /Fc with a peak split of 174 mV, which lead to a theoretical potential difference of 2.91 V.

  8. Synthesis, cytotoxicity and molecular modelling studies of new phenylcinnamide derivatives as potent inhibitors of cholinesterases.

    Science.gov (United States)

    Saeed, Aamer; Mahesar, Parvez Ali; Zaib, Sumera; Khan, Muhammad Siraj; Matin, Abdul; Shahid, Mohammad; Iqbal, Jamshed

    2014-05-06

    The present study reports the synthesis of cinnamide derivatives and their biological activity as inhibitors of both cholinesterases and anticancer agents. Controlled inhibition of brain acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) may slow neurodegeneration in Alzheimer's diseases (AD). The anticholinesterase activity of phenylcinnamide derivatives was determined against Electric Eel acetylcholinesterase (EeAChE) and horse serum butyrylcholinesterase (hBChE) and some of the compounds appeared as moderately potent inhibitors of EeAChE and hBChE. The compound 3-(2-(Benzyloxy)phenyl)-N-(3,4,5-trimethoxyphenyl)acrylamide (3i) showed maximum activity against EeAChE with an IC50 0.29 ± 0.21 μM whereas 3-(2-chloro-6-nitrophenyl)-N-(3,4,5-trimethoxyphenyl)acrylamide (3k) was proved to be the most potent inhibitor of hBChE having IC50 1.18 ± 1.31 μM. To better understand the enzyme-inhibitor interaction of the most active compounds toward cholinesterases, molecular modelling studies were carried out on high-resolution crystallographic structures. The anticancer effects of synthesized compounds were also evaluated against cancer cell line (lung carcinoma). The compounds may be useful leads for the design of a new class of anticancer drugs for the treatment of cancer and cholinesterase inhibitors for Alzheimer's disease (AD). Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  9. Synthesis and Antimicrobial Activities of Some New 1,2,4-Triazole Derivatives

    Directory of Open Access Journals (Sweden)

    Hakan Bektaş

    2010-04-01

    Full Text Available Some novel 4,5-disubstituted-2,4-dihydro-3H-1,2,4-triazol-3-one (3, 6, 8, 9 derivatives and or 3-(4-methylphenyl[1,2,4]triazolo[3,4-b][1,3]benzoxazole (5 were synthesized from the reaction of various ester ethoxycarbonylhydrazones (1a-e with several primary amines. The synthesis of 4-amino-5-(4-chlorophenyl-2-[(5-mercapto-1,3,4-oxadiazol-2-ylmethyl]-2,4-dihydro-3H-1,2,4-triazol-3-one (13 was performed starting from 4-Amino-5-(4-chlorophenyl-2,4-dihydro-3H-1,2,4-triazol-3-one (2 by four steps; then 13 was converted to the corresponding Schiff base (14 by using 4-methoxybenzaldehyde. Finally, two Mannich base derivatives of 14 were obtained by using morpholine or methyl piperazine as amine component. All newly synthesized compounds were screened for their antimicrobial activities and some of which were found to possess good or moderate activities against the test microorganisms.

  10. Synthesis and biological evaluation of novel 5-hydroxylaminoisoxazole derivatives as lipoxygenase inhibitors and metabolism enhancing agents.

    Science.gov (United States)

    Averina, Elena B; Vasilenko, Dmitry A; Gracheva, Yulia A; Grishin, Yuri K; Radchenko, Eugene V; Burmistrov, Vladimir V; Butov, Gennady M; Neganova, Margarita E; Serkova, Tatyana P; Redkozubova, Olga M; Shevtsova, Elena F; Milaeva, Elena R; Kuznetsova, Tamara S; Zefirov, Nikolay S

    2016-02-15

    A versatile synthesis of novel 5-hydroxylaminoisoxazoles bearing adamantane moieties has been accomplished using the heterocyclization reactions of readily available unsaturated esters by the treatment with tetranitromethane in the presence of triethylamine and subsequent reduction of resulting 5-nitroisoxazoles by SnCl2 with the participation of THF. A number of obtained isoxazole derivatives were evaluated for their antioxidative activity, inhibition of lipoxygenases and impact on the rat liver mitochondria. The majority of tested compounds demonstrated moderate antiradical activity in DPPH test (up to EC50 16μM). The same compounds strongly inhibited soybean lipoxygenase (up to IC50 0.4μM) and Fe(2+)- and Fe(3+)-induced lipid peroxidation (LP) of rat brain cortex homogenate (up to IC50 0.3μM). All tested isoxazole derivatives promoted the phosphorylating respiratory activity simultaneously with maximal stimulated respiratory activity of mitochondria and do not reveal any toxicity towards the primary culture of rat cortex neurons. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. 5-Alkylresorcinol Derivatives from the Bryozoan Schizomavella mamillata: Isolation, Synthesis, and Antioxidant Activity

    Directory of Open Access Journals (Sweden)

    María J. Ortega

    2017-11-01

    Full Text Available The chemical study of the bryozoan Schizomavella mamillata has led to the isolation of six new 5-alkylresorcinol derivatives, schizols A–F (1–6, whose structures were established by spectrocospic means. Schizol A (1 exhibits a (E-6-phenylnon-5-enyl moiety linked to the C-5 of a resorcinol ring, while in schizol B (2 the substituent at C-5 contains an unusual 1,2-dihydrocyclobutabenzene moiety. Schizols C (3 and D (4 have been characterized as the 1-sulfate derivatives of 1 and 2, respectively, and schizols E (5 and F (6 are the corresponding 1,3-disulfates. Schizol A (1 has been synthetized from 3,5-dimethoxybenzaldehyde through a sequence involving a Wittig reaction for the construction of the C-1′,C-2′ bond and a Julia–Kocienski olefination for the synthesis of the C-5′,C-6′ double bond. In the ABTS (2,2′-azinobis(3-ethylbenzothiazoline-6-sulphonic acid antioxidant assay, the natural compounds schizol A (1 and schizol B (2 showed higher radical scavenging activity than the Trolox standard.

  12. Partial catalytic oxidation of CH{sub 4} to synthesis gas for power generation - Final report

    Energy Technology Data Exchange (ETDEWEB)

    Mantzaras, I.; Schneider, A.

    2006-03-15

    The partial oxidation of methane to synthesis gas over rhodium catalysts has been investigated experimentally and numerically in the pressure range of 4 to 10 bar. The methane/oxidizer feed has been diluted with large amounts of H{sub 2}O and CO{sub 2} (up to 70% vol.) in order to simulate new power generation cycles with large exhaust gas recycle. Experiments were carried out in an optically accessible channel-flow reactor that facilitated laser-based in situ measurements, and also in a subscale gas-turbine catalytic reactor. Full-elliptic steady and transient two-dimensional numerical codes were used, which included elementary hetero-/homogeneous chemical reaction schemes. The following are the key conclusions: a) Heterogeneous (catalytic) and homogeneous (gas-phase) schemes have been validated for the partial catalytic oxidation of methane with large exhaust gas recycle. b) The impact of added H{sub 2}O and CO{sub 2} has been elucidated. The added H{sub 2}O increased the methane conversion and hydrogen selectivity, while it decreased the CO selectivity. The chemical impact of CO{sub 2} (dry reforming) was minimal. c) The numerical model reproduced the measured catalytic ignition times. It was further shown that the chemical impact of H{sub 2}O and CO{sub 2} on the catalytic ignition delay times was minimal. d) The noble metal dispersion increased with different support materials, in the order Rh/{alpha}-Al{sub 2}O{sub 3}, Rh/ZrO{sub 2}, and Rh/Ce-ZrO{sub 2}. An evident relationship was established between the noble metal dispersion and the catalytic behavior. (authors)

  13. Synthesis of a hierarchically structured zeolite-templated carbon starting from fly ash-derived zeolite X

    CSIR Research Space (South Africa)

    Musyoka, Nicholas M

    2014-05-01

    Full Text Available A hierarchically structured zeolite derived from coal fly ash was used as a hard templating agent for the synthesis of a templated carbonaceous material. The samples were characterized using XRD, SEM, TEM, TGA, EDS and BET. The resulting carbon had...

  14. Visible light-photocatalysed carbazole synthesis via a formal (4+2) cycloaddition of indole-derived bromides and alkynes.

    Science.gov (United States)

    Yuan, Zhi-Guang; Wang, Qiang; Zheng, Ang; Zhang, Kai; Lu, Liang-Qiu; Tang, Zilong; Xiao, Wen-Jing

    2016-04-14

    We successfully developed an unprecedented route to carbazole synthesis through a visible light-photocatalysed formal (4+2) cycloaddition of indole-derived bromides and alkynes. This novel protocol features extremely mild conditions, a broad substrate scope and high reaction efficiency.

  15. Synthesis of pyrimidinic nucleotides and nucleosides labelled with carbon 14, through tri-methylsilylated and lithiated derivatives

    International Nuclear Information System (INIS)

    Godbillon, Jacques

    1972-01-01

    After a presentation of the trimethysilylation, lithiation, and methylation processes, this research thesis reports the synthesis of methyl carbon 14 - 5 - uridine, of ethyl carbon 14 - 5 - desoxy - 2' - uridine, and of thymidine monophosphate - 5' (methyl carbon 14) by using silylated and lithiated derivatives. The author also reports preliminary studies of biological studies of the trimethylsilyl-5-uridine and of the iodine-6-thymine

  16. Three Component Synthesis of Substituted 4H-[1,3]Dioxin Derivatives Under Solvent-Free Conditions

    Directory of Open Access Journals (Sweden)

    Mohammad Reza Hosseini-Tabatabaei

    2012-01-01

    Full Text Available Reaction between aryl aldehydes, acetylacetone and alkyl isocyanides in solvent-free conditions provided a simple and efficient one-pot route for the synthesis of 1-(2-alkylamino-6-methyl-4-aryl-4H-[1,3]dioxin-5-ylethanone derivatives in excellent yields.

  17. A new practical approach towards the synthesis of unsymmetric and symmetric 1,10-phenanthroline derivatives at room temperature.

    Science.gov (United States)

    Cheng, Yongfeng; Han, Xuesong; Ouyang, Huangche; Rao, Yu

    2012-03-18

    An efficient method towards synthesis of 1,10-phenanthrolines is described. Through Lewis acid-catalyzed annulation reaction between 3-ethoxycyclobutanones and 8-aminoquinolines, a variety of unsymmetric and symmetric 1,10-phenanthroline derivatives were readily prepared with high regioselectivity at room temperature.

  18. Effects of calcination and activation conditions on ordered mesoporous carbon supported iron catalysts for production of lower olefins from synthesis gas

    NARCIS (Netherlands)

    Oschatz, M; van Deelen, T W; Weber, J L; Lamme, W S; Wang, G; Goderis, B; Verkinderen, O; Dugulan, A I; de Jong, K P

    2016-01-01

    Lower C2–C4 olefins are important commodity chemicals usually produced by steam cracking of naphtha or fluid catalytic cracking of vacuum gas oil. The Fischer–Tropsch synthesis of lower olefins (FTO) with iron-based catalysts uses synthesis gas as an alternative feedstock. Nanostructured carbon

  19. Hydrothermal synthesis of h-MoO3 microrods and their gas sensing properties to ethanol

    International Nuclear Information System (INIS)

    Liu, Yueli; Yang, Shuang; Lu, Yu; Podval’naya, Natal’ya V.; Chen, Wen; Zakharova, Galina S.

    2015-01-01

    Highlights: • A simple hydrothermal acid-free method for the synthesis of h-MoO 3 microrods with the hexagonal cross-section is reported. • The h-MoO 3 phase is transformed to α-MoO 3 at 439 °C. • The h-MoO 3 microrods were employed to fabricate gas sensors to detect ethanol. • Sensor showed highest response with a sensitivity of 8.24–500 ppm C 2 H 5 OH at operating temperature of 332 °C. - Abstract: Hexagonal molybdenum trioxide (h-MoO 3 ) microrods were successfully synthesized via a novel and facile hydrothermal route from peroxomolybdate solution with the presence of NH 4 Cl as the mineralizer. A variety of the techniques including X-ray diffraction (XRD), scanning electron microscopy (SEM), differential scanning calorimetry combined with the thermal gravimetric analysis (DSC–TG) were used to characterize the product. The gas sensing test indicates that h-MoO 3 microrods have a good response to 5–500 ppm ethanol in the range of 273–380 °C, and the optimum operating temperature is 332 °C with a high sensitivity of 8.24 to 500 ppm ethanol. Moreover, it also has a good selectivity toward ethanol gas if compared with other gases, such as ammonia, methanol and toluene. The sensing mechanism of h-MoO 3 microrods to ethanol was also discussed.

  20. Synthesis of 2-phenyl- and 2,3-diphenyl-quinolin-4-carboxylic acid derivatives

    International Nuclear Information System (INIS)

    Elhadi, S. A.

    2004-09-01

    Quinolin derivatives are a group of compounds known to possess a wide range of biological activities. The chemistry of quinolines together with their corresponding aldehydes were dealt with in chapter one of this study. Special emphasis was given to the chemistry of benzaldehyde. Twenty five 2-phenyl- and 2,3-diphenyl-quinolin-4-carboxylic acid derivatives together with their corresponding intermediates were prepared in this work. Basically, the synthetic design of these compounds arise from the appropriate disconnections of the target 2-phenyl and 2,3-diphenyl-quinolin-4-carboxylic acids. The retro synthesis analysis of these compounds reveals pyruvic acid, aromatic amine and benzaldehyde or phenyl pyruvic acid, aromatic amine and benzaldehyde as possible logical precursors for 2-phenyl-and 2,3-diphenyl- quinoline-4-carboxylic acids respectively. The purity and identities of the synthesized compounds were elucidated through chromatographic and spectroscopic techniques. The compounds were heavily subjected to spectroscopic analysis (UV, IR, GC/MS, 1 H-and 13 C- NMR). The appropriate disconnections and the mechanisms of the corresponding reactions were given and discussed in chapter three. The spectral data were interpreted and correlated with the target structures. The prepared 2-phenyl- and 2,3-diphenyl-quinoline-4-carboxylic acid derivatives were screened for their antibacterial activity. The compounds were tested against the standard bacterial organisms B. subtilis, S. aureus, E. coli and P. vulgaris. Some of these compounds were devoid of antibacterial activity against S. aureus and P. vulgaris, while others showed moderate activity. All of the tested compounds showed an activity against B. subtilis and E. coli. 2,3-diphenyl -6-sulphanilamide-quinolin-4-carboxylic acid showed the highest activity against the four standard tested organisms.(Author)

  1. Synthesis of 2-phenyl- and 2,3-diphenyl-quinolin-4-carboxylic acid derivatives

    Energy Technology Data Exchange (ETDEWEB)

    Elhadi, S A [Department of Chemistry, Faculty of Education, University of Khartoum, Khartoum (Sudan)

    2004-09-01

    Quinolin derivatives are a group of compounds known to possess a wide range of biological activities. The chemistry of quinolines together with their corresponding aldehydes were dealt with in chapter one of this study. Special emphasis was given to the chemistry of benzaldehyde. Twenty five 2-phenyl- and 2,3-diphenyl-quinolin-4-carboxylic acid derivatives together with their corresponding intermediates were prepared in this work. Basically, the synthetic design of these compounds arise from the appropriate disconnections of the target 2-phenyl and 2,3-diphenyl-quinolin-4-carboxylic acids. The retro synthesis analysis of these compounds reveals pyruvic acid, aromatic amine and benzaldehyde or phenyl pyruvic acid, aromatic amine and benzaldehyde as possible logical precursors for 2-phenyl-and 2,3-diphenyl- quinoline-4-carboxylic acids respectively. The purity and identities of the synthesized compounds were elucidated through chromatographic and spectroscopic techniques. The compounds were heavily subjected to spectroscopic analysis (UV, IR, GC/MS, {sup 1}H-and {sup 13}C- NMR). The appropriate disconnections and the mechanisms of the corresponding reactions were given and discussed in chapter three. The spectral data were interpreted and correlated with the target structures. The prepared 2-phenyl- and 2,3-diphenyl-quinoline-4-carboxylic acid derivatives were screened for their antibacterial activity. The compounds were tested against the standard bacterial organisms B. subtilis, S. aureus, E. coli and P. vulgaris. Some of these compounds were devoid of antibacterial activity against S. aureus and P. vulgaris, while others showed moderate activity. All of the tested compounds showed an activity against B. subtilis and E. coli. 2,3-diphenyl -6-sulphanilamide-quinolin-4-carboxylic acid showed the highest activity against the four standard tested organisms.(Author)

  2. Evaluation of the LMFBR cover gas source term and synthesis of the associated R and D

    International Nuclear Information System (INIS)

    Balard, F.; Carluec, B.

    1996-01-01

    K, Germany), sodium aerosols formation in the cover gas (UK, Japan, France), fuel degassing (Mignanelli synthesis, UK). (author)

  3. Solvent-Free Synthesis of Quaternary Metal Sulfide Nanoparticles Derived from Thiourea

    KAUST Repository

    Bhunia, Manas Kumar; Abou-Hamad, Edy; Anjum, Dalaver H.; Gurinov, Andrei; Takanabe, Kazuhiro

    2017-01-01

    The synthesis of metal sulfide (MS) materials with sizes in the sub-10 nm regime often requires capping agents with long hydrocarbon chains that affect their structures and properties. Herein, this study presents a molten-state synthesis method

  4. Synthesis of new oxovanadium (IV) complexes of potential insulinmimetic activity with coumarin-3-carboxylic acid ligands and substituted derivatives

    International Nuclear Information System (INIS)

    Salas Fernandez, Paloma; Alvino de la Sota, Nora; Galli Rigo-Righi, Carla

    2013-01-01

    This work comprises the design and synthesis of four new oxovanadium (IV) complexes, a metal which possesses insulin-mimetic action. Coumarin-3-carboxylic acid and three of its 6 -and 6,8- derivatives were used as ligands. Coumarins are of interest due to their well-known biological properties and pharmacological applications; these include the insulino-sensibilizing effect of certain alcoxy-hydroxy-derivatives which might lead to the eventual existence of a synergetic effect with the active metal center. The synthesis of the vanadyl complexes was preceded by the synthesis of the coumarin-3-carboxylic acid and its 6-bromo- derivative, as well as the syntheses of three derivatives not previously reported: 6-bromo-8-metoxi-, 6-bromo-8-nitro-, and 6-bromo-8-hydroxy-, which were prepared by a Knoevenagel condensation reaction. The complexes, on their part, were prepared by a metathesis reaction between VOSO 4 and the corresponding ligands, on the basis of methods reported for other vanadyl complexes and under strict pH control. The coumarin-3-carboxylic ligands and the derivatives were characterized by 1 H-NMR-, FTIR- and UV-Vis-spectroscopy. In the case of the complexes, their paramagnetic character did not allow for NMR characterization, being thus identified by FT-IR-spectroscopy and by the quantitative determination of their vanadium contents. (author)

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

    Science.gov (United States)

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

    2018-01-01

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

  6. Synthesis of new 3-(2-aminothiazol-4-yl-4-hydroxy-2H-chromen-2-one derivatives

    Directory of Open Access Journals (Sweden)

    S. SUKDOLAK

    2006-06-01

    Full Text Available Aminothiazole derivatives of 4-hydroxy-2H-chromen-2-one were prepared by the Hantzsch reaction1 using 3-(2-bromoacetyl-4-hydroxy-2H-chromen-2-one and thiourea derivatives. Starting compound for this synthesis 3-(2-bromoacetyl-4-hydroxy- 2H-chromen-2-one (1 was prepared previously.2 Also, for this synthesis we used thiourea derivatives (2a–j as compounds which possess groups with biological activity. Reactions are carried out in refluxing ethanol for a period of 30 – 45 min. Final products (3a–j are obtained in a high yield. Chemical structure of the obtained compounds was confirmed by elemental and structural analysis (IR and 1H NMR spectroscopy.

  7. A relative permeability model to derive fractional-flow functions of water-alternating-gas and surfactant-alternating-gas foam core-floods

    International Nuclear Information System (INIS)

    Al-Mossawy, Mohammed Idrees; Demiral, Birol; Raja, D M Anwar

    2013-01-01

    Foam is used in enhanced oil recovery to improve the sweep efficiency by controlling the gas mobility. The surfactant-alternating-gas (SAG) foam process is used as an alternative to the water-alternating-gas (WAG) injection. In the WAG technique, the high mobility and the low density of the gas lead the gas to flow in channels through the high permeability zones of the reservoir and to rise to the top of the reservoir by gravity segregation. As a result, the sweep efficiency decreases and there will be more residual oil in the reservoir. The foam can trap the gas in liquid films and reduces the gas mobility. The fractional-flow method describes the physics of immiscible displacements in porous media. Finding the water fractional flow theoretically or experimentally as a function of the water saturation represents the heart of this method. The relative permeability function is the conventional way to derive the fractional-flow function. This study presents an improved relative permeability model to derive the fractional-flow functions for WAG and SAG foam core-floods. The SAG flow regimes are characterized into weak foam, strong foam without a shock front and strong foam with a shock front. (paper)

  8. Facile synthesis of improved room temperature gas sensing properties of TiO2 nanostructures: Effect of acid treatment

    CSIR Research Space (South Africa)

    Tshabalala, Zamaswazi P

    2016-03-01

    Full Text Available and Actuators B: Chemical Facile synthesis of improved room temperature gas sensing properties of TiO2 nanostructures: Effect of acid treatment Z.P. Tshabalalaa,b, D.E. Motaunga,∗, G.H. Mhlongoa,∗, O.M. Ntwaeaborwab,∗ a DST/CSIR, National Centre...

  9. Ambient temperature aqueous synthesis of ultrasmall copper doped ceria nanocrystals for the water gas shift and carbon monoxide oxidation reactions

    Energy Technology Data Exchange (ETDEWEB)

    Curran, Christopher D. [Department of Chemical and Biomolecular Engineering; Lehigh University; Bethlehem; USA; Lu, Li [Department of Materials Science and Engineering; Lehigh University; Bethlehem; USA; Kiely, Christopher J. [Department of Chemical and Biomolecular Engineering; Lehigh University; Bethlehem; USA; Department of Materials Science and Engineering; McIntosh, Steven [Department of Chemical and Biomolecular Engineering; Lehigh University; Bethlehem; USA

    2018-01-01

    Ultra-small CuxCe1-xO2-δnanocrystals were prepared through a room temperature, aqueous synthesis method, achieving high copper doping and low water gas shift activation energy.

  10. Effect of surface composition of yttrium-stabilized zirconia on partial oxidation of methane to synthesis gas.

    NARCIS (Netherlands)

    Zhu, J.J.; van Ommen, J.G.; Knoester, A.; Lefferts, Leonardus

    2005-01-01

    Catalytic partial oxidation of methane to synthesis gas (CPOM) over yttrium-stabilized zirconia (YSZ) was studied within a wide temperature window (500¿1100 °C). The catalysts were characterized by X-ray fluorescence (XRF) and low-energy ion scattering (LEIS). The influence of calcination

  11. The performance of a thermophilic microbial fuel cell fed with synthesis gas.

    Science.gov (United States)

    Hussain, A; Mehta, P; Raghavan, V; Wang, H; Guiot, S R; Tartakovsky, B

    2012-08-10

    This study demonstrated electricity generation in a thermophilic microbial fuel cell (MFC) operated on synthesis gas (syngas) as the sole electron donor. At 50°C, a volumetric power output of 30-35 mWL(R)(-1) and a syngas conversion efficiency of 87-98% was achieved. The observed pathway of syngas conversion to electricity primarily consisted of a two-step process, where the carbon monoxide and hydrogen were first converted to acetate, which was then consumed by the anodophilic bacteria to produce electricity. A denaturing gradient gel electrophoresis (DGGE) analysis of the 16S rDNA revealed the presence of Geobacter species, Acetobacter, methanogens and several uncultured bacteria and archaea in the anodic chamber. Crown Copyright © 2012. Published by Elsevier Inc. All rights reserved.

  12. Synthesis and integration of one-dimensional nanostructures for chemical gas sensing applications

    Science.gov (United States)

    Parthangal, Prahalad Madhavan

    The need for improved measurement technology for the detection and monitoring of gases has increased tremendously for maintenance of domestic and industrial health and safety, environmental surveys, national security, food-processing, medical diagnostics and various other industrial applications. Among the several varieties of gas sensors available in the market, solid-state sensors are the most popular owing to their excellent sensitivity, ruggedness, versatility and low cost. Semiconducting metal oxides such as tin oxide (SnO2), zinc oxide (ZnO), and tungsten oxide (WO3) are routinely employed as active materials in these sensors. Since their performance is directly linked to the exposed surface area of the sensing material, one-dimensional nanostructures possessing very high surface to volume ratios are attractive candidates for designing the next generation of sensors. Such nano-sensors also enable miniaturization thereby reducing power consumption. The key to achieve success in one-dimensional nanotechnologies lies in assembly. While synthesis techniques and capabilities continue to expand rapidly, progress in controlled assembly has been sluggish due to numerous technical challenges. In this doctoral thesis work, synthesis and characterization of various one-dimensional nanostructures including nanotubes of SnO2, and nanowires of WO3 and ZnO, as well as their direct integration into miniature sensor platforms called microhotplates have been demonstrated. The key highlights of this research include devising elegant strategies for growing metal oxide nanotubes using carbon nanotubes as templates, substantially reducing process temperatures to enable growth of WO3 nanowires on microhotplates, and successfully fabricating a ZnO nanowire array based sensor using a hybrid nanowire-nanoparticle assembly approach. In every process, the gas-sensing properties of one-dimensional nanostructures were observed to be far superior in comparison with thin films of the same

  13. Comparison of Conventional and Microwave-assisted Synthesis of Benzimidazole Derivative from Citronellal in Kaffir lime oil (Citrus hystrix DC.)

    Science.gov (United States)

    Warsito, W.; Noorhamdani, A. S.; Suratmo; Dwi Sapri, R.; Alkaroma, D.; Azhar, A. Z.

    2018-04-01

    Simple method has been used for the synthesis of benzimidazole derivative from citronellal in kaffir lime oil under microwave irradiation. These compounds were synthesized also by conventional heating for comparison. In addtion, microwave-assited synthesis was also compared between using to dichloromethane and methanol solvents with variation of reaction time for 30 to 70 minutes and 4 to 12 h for conventional heating. The 2-citronellyl benzimidazole compound synthesized were characterised by FT-IR, GC-MS, 1H and 13C NMR spectroscopy. Comparison between conventional and microwave-assisted synthesis was done by comparing between correlation of reaction time and percentage yield. The time optimum of microwave-assisted and conventional synthesis using dichloromethane solvent respectively at 60 minutes (yield 19.23%) and 8 hours (yield 11.54%). In addition, microwave-assited synthesis increasing 157.81 times compared by conventional heating. While using methanol solvent tends to increase linearly however the percentage of yield only 0.77 times of synthesis using dichloromethane solvent.

  14. Gas-phase laser synthesis of aggregation-free, size-controlled hydroxyapatite nanoparticles

    International Nuclear Information System (INIS)

    Bapat, Parimal V.; Kraft, Rebecca; Camata, Renato P.

    2012-01-01

    Nanophase hydroxyapatite (HA) is finding applications in many areas of biomedical research, including bone tissue engineering, drug delivery, and intracellular imaging. Details in chemical composition, crystal phase makeup, size, and shape of HA nanoparticles play important roles in achieving the favorable biological responses required in these applications. Most of the nanophase HA synthesis techniques involve solution-based methods that exhibit substantial aggregation of particles upon precipitation. Typically these methods also have limited control over the particle size and crystal phase composition. In this study, we describe the gas-phase synthesis of aggregation-free, size-controlled HA nanoparticles with mean size in the 20–70 nm range using laser ablation followed by aerosol electrical mobility classification. Nanoparticle deposits with adjustable number concentration were obtained on solid substrates. Particles were characterized by transmission electron microscopy, atomic force microscopy, and X-ray diffraction. Samples are well represented by log-normal size distributions with geometric standard deviation σ g ≈ 1.2. The most suitable conditions for HA nanoparticle formation at a laser fluence of 5 J/cm 2 were found to be a temperature of 800 °C and a partial pressure of water of 160 mbar.

  15. Controlled gas-liquid interfacial plasmas for synthesis of nano-bio-carbon conjugate materials

    Science.gov (United States)

    Kaneko, Toshiro; Hatakeyama, Rikizo

    2018-01-01

    Plasmas generated in contact with a liquid have been recognized to be a novel reactive field in nano-bio-carbon conjugate creation because several new chemical reactions have been yielded at the gas-liquid interface, which were induced by the physical dynamics of non-equilibrium plasmas. One is the ion irradiation to a liquid, which caused the spatially selective dissociation of the liquid and the generation of additive reducing and oxidizing agents, resulting in the spatially controlled synthesis of nanostructures. The other is the electron irradiation to a liquid, which directly enhanced the reduction action at the plasma-liquid interface, resulting in temporally controlled nanomaterial synthesis. Using this novel reaction field, gold nanoparticles with controlled interparticle distance were synthesized using carbon nanotubes as a template. Furthermore, nanoparticle-biomolecule conjugates and nanocarbon-biomolecule conjugates were successfully synthesized by an aqueous-solution contact plasma and an electrolyte plasma, respectively, which were rapid and low-damage processes suitable for nano-bio-carbon conjugate materials.

  16. Niobium carbide synthesis by solid-gas reaction using a rotating cylinder reactor

    International Nuclear Information System (INIS)

    Fontes, F.A.O.; Gomes, K.K.P.; Oliveira, S.A.; Souza, C.P.; Sousa, J.F.; Rio Grande do Norte Univ., Natal, RN

    2004-01-01

    A rotating cylinder reactor was designed for the synthesis of niobium carbide powders at 1173 K. Niobium carbide, NbC, was prepared by carbothermal reduction starting from commercial niobium pentoxide powders. The reactor was heated using a custom-made, two-part, hinged, electric furnace with programmable temperature control. The design and operational details of the reactor are presented. The longitudinal temperature gradient inside the reactor was determined. Total reaction time was monitored by a gas chromatograph equipped with an FID detector for determination of methane concentrations. The results show that time of reaction depended on rotation speed. NbC was also prepared in a static-bed alumina reactor using the same conditions as in the previous case. The niobium carbide powders were characterized by X-ray diffraction and compared with commercially available products. Morphological, particle size distribution and surface area analyses were obtained using SEM, LDPS and BET, respectively. Therefore, the present study offers a significant technological contribution to the synthesis of NbC powders in a rotating cylinder reactor. (author)

  17. Hydrogen enrichment and separation from synthesis gas by the use of a membrane reactor

    International Nuclear Information System (INIS)

    Sanchez, J.M.; Barreiro, M.M.; Marono, M.

    2011-01-01

    One of the objectives of the CHRISGAS project was to study innovative gas separation and gas upgrading systems that have not been developed sufficiently yet to be tested at a demonstration scale within the time frame of the project, but which show some attractive merits and features for further development. In this framework CIEMAT studied, at bench scale, hydrogen enrichment and separation from syngas by the use of membranes and membrane catalytic reactors. In this paper results about hydrogen separation from synthesis gas by means of selective membranes are presented. Studies dealt with the evaluation of permeation and selectivity to hydrogen of prepared and pre-commercial Pd-based membranes. Whereas prepared membranes turned out to be non-selective, due to discontinuities of the palladium layer, studies conducted with the pre-commercial membrane showed that by means of a membrane reactor it is possible to completely separate hydrogen from the other gas components and produce pure hydrogen as a permeate stream, even in the case of complex reaction system (H 2 /CO/CO 2 /H 2 O) under WGS conditions gas mixtures. The advantages of using a water-gas shift membrane reactor (MR) over a traditional fixed bed reactor (TR) have also been studied. The experimental device included the pre-commercial Pd-based membrane and a commercial high temperature Fe-Cr-based, WGS catalyst, which was packed in the annulus between the membrane and the reactor outer shell. Results show that in the MR concept, removal of H 2 from the reaction side has a positive effect on WGS reaction, reaching higher CO conversion than in a traditional packed bed reactor at a given temperature. On increasing pressure on the reaction side permeation is enhanced and hence carbon monoxide conversion increases. -- Highlights: → H 2 enrichment and separation using a bench-scale membrane reactor MR is studied. → Permeation and selectivity to H 2 of Pd-based membranes was determined. → Complete separation

  18. Synthesis and optical properties of enantiomeric cinchonidine/cinchonine-terpyridine derivatives and their metal complexes

    International Nuclear Information System (INIS)

    Wang, Hui-Ting; Wu, Wen-Jie; Liu, Jiang; Chen, Meng; Qian, Dong-Jin; Zhang, Li; Liu, Minghua

    2016-01-01

    We report here the synthesis and spectroscopic properties of two enantiomeric chiral tridentate ligands (TPyCCD and TPyCCN) composed of terpyridine (TPy) and cinchonidine (CCD) or cinchonine (CCN) substituent, as well as their metal complexes with Zn 2+ , Fe 2+ , Eu 3+ , and Tb 3+ ions. For the pure ligands, the fluorescent emission intensity increased as their concentrations increased in the dilute solutions, but they decreased when the concentrations were greater than 6.9×10 −6 mol/l due to concentration quenching. No significant influence on ligand luminescence was observed for the Zn 2+ /Fe 2+ –TPyCCD and –TPyCCN metal complexes. Their lanthanide (Eu 3+ and Tb 3+ ) complexes displayed both ligand and lanthanide ion emissions, suggesting that the excited energy of both ligands could be transferred to the central Eu 3+ and Tb 3+ ions. Mirror-image circular dichroism spectra were recorded, with several signals centered at about 230, 250–270, 296, and 320 nm; the first ones corresponded to the chiral CCD and CCN substituents, while the latter ones corresponded to the TPy substituent and the metal–TPy (M-TPy) coordination units. It is suggested that the chirality of TPy and the metal complexes was induced by the coexisting chiral CCD and CCN substituents. In addition, due to formation of the metal complexes, the relative intensity of the chiral signals of M–TPy coordination units was enhanced at about 320 nm. - Highlights: • Cinchona alkaloid-terpyridine derivatives and metal complexes were prepared. • Cinchona alkaloid-terpyridine derivatives gave off luminescence at 362 nm. • Ligand excited energy could efficiently transferred to lanthanide ions. • Chirality of terpyridine and metal complexes was induced.

  19. Synthesis and Characterization of Quaternary Metal Chalcogenide Aerogels for Gas Separation and Volatile Hydrocarbon Adsorption

    KAUST Repository

    Edhaim, Fatimah A.

    2017-11-01

    In this dissertation, the metathesis route of metal chalcogenide aerogel synthesis was expanded by conducting systematic studies between polysulfide building blocks and the 1st-row transition metal linkers. Resulting materials were screened as sorbents for selective gas separation and volatile organic compounds adsorption. They showed preferential adsorption of polarizable gases (CO2) and organic compounds (toluene). Ion exchange and heavy metal remediation properties have also been demonstrated. The effect of the presence of different counter-ion within chalcogel frameworks on the adsorption capacity of the chalcogels was studied on AFe3Zn3S17 (A= K, Na, and Rb) chalcogels. The highest adsorption capacity toward hydrocarbons and gases was observed on Rb based chalcogels. Adopting a new building block [BiTe3]3- with the 1st-row transition metal ions results in the formation of three high BET surface area chalcogels, KCrBiTe3, KZnBiTe3, and KFeBiTe3. The resulting chalcogels showed preferential adsorption of toluene vapor, and remarkable selectivity of CO2, indicating the potential future use of chalcogels in adsorption-based gas or hydrocarbon separation processes. The synthesis and characterization of the rare earth chalcogels NaYSnS4, NaGdSnS4, and NaTbSnS4 are also reported. Rare earth metal ions react with the thiostannate clusters in formamide solution forming extended polymeric networks by gelation. Obtained chalcogels have high BET surface areas, and showed notable adsorption capacity toward CO2 and toluene vapor. These chalcogels have also been engaged in the absorption of different organic molecules. The results reveal the ability of the chalcogels to distinguish among organic molecules on their electronic structures; hence, they could be used as sensors. Furthermore, the synthesis of metal chalcogenide aerogels Co0.5Sb0.33MoS4 and Co0.5Y0.33MoS4 by the sol-gel method is reported. In this system, the building blocks [MoS4]2- chelated with Co2+ and (Sb3

  20. Natural gas conversion new route using halogen derivatives; Nova rota de conversao de gas natural utilizando derivados halogenados

    Energy Technology Data Exchange (ETDEWEB)

    Noronha, Leandro A.; Mota, Claudio J.A. [Universidade Federal, Rio de Janeiro, RJ (Brazil). Centro de Tecnologia]. E-mail: noronha@iq.ufrj.br; Sousa Aguiar, E. Falabella [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil). Centro de Pesquisas

    2003-07-01

    Natural gas will have important position in the next decades. Nowadays, there is high demand for petrochemicals products, such as ethene and propene. With the nafta price variation, the development of alternative routes from natural gas will be stimulate, as occur in Rio de Janeiro. Between the main technologies for the natural gas use, arise the gas to liquids (GTL) routes for the conversion to hydrocarbons. Therefore, will be studied the transformation of methyl chloride to light olefins (ethene and propene) and other hydrocarbons in zeolitic catalysts. All of these reactions will be simulate occurring in the zeolitic surface, using a cluster that represents very much the catalyst structure. (author)

  1. Novel vanillin derivatives: Synthesis, anti-oxidant, DNA and cellular protection properties.

    Science.gov (United States)

    Scipioni, Matteo; Kay, Graeme; Megson, Ian; Kong Thoo Lin, Paul

    2018-01-01

    Antioxidants have been the subject of intense research interest mainly due to their beneficial properties associated with human health and wellbeing. Phenolic molecules, such as naturally occurring Resveratrol and Vanillin, are well known for their anti-oxidant properties, providing a starting point for the development of new antioxidants. Here we report, for the first time, the synthesis of a number of new vanillin through the reductive amination reaction between vanillin and a selection of amines. All the compounds synthesised, exhibited strong antioxidant properties in DPPH, FRAP and ORAC assays, with compounds 1b and 2c being the most active. The latter also demonstrated the ability to protect plasmid DNA from oxidative damage in the presence of the radical initiator AAPH. At cellular level, neuroblastoma SH-SY5Y cells were protected from oxidative damage (H 2 O 2 , 400 μM) with both 1b and 2c. The presence of a tertiary amino group, along with the number of vanillin moieties in the molecule contribute for the antioxidant activity. Furthermore, the delocalization of the electron pair of the nitrogen and the presence of an electron donating substituent to enhance the antioxidant properties of this new class of compounds. In our opinion, vanillin derivatives 1b and 2c described in this work can provide a viable platform for the development of antioxidant based therapeutics. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  2. Synthesis and characterization of eggshell-derived hydroxyapatite via mechanochemical method: A comparative study

    Science.gov (United States)

    Hamidi, A. A.; Salimi, M. N.; Yusoff, A. H. M.

    2017-04-01

    The focus of bone graft properties has developed through generations, from the ability to withstand mechanical stress to the ability to integrate with the biological structure. In recent years, the use of hydroxyapatite (HA) as bone graft material in orthopedic and dental applications has been increasing. HA is a natural occuring mineral with excellent bioactivity but relatively poor mechanical properties. It constitutes 96% portion of enamel in teeth and 67% portion of bone. HA can be extracted from animal bones or fabricated from synthetic or biologic sources. In this study, eggshells were used as raw material to synthesize eggshell-derived HA (EHA) via mechanochemical method. The synthesis of EHA involved CaO, which was obtained from the calcination of eggshells, and reaction with dicalcium hydrogen phosphate dihydrous (DCPD) or phosphoric acid (H3PO4). The effects of rotational speed and heat treatment temperature on EHA's characteristics were investigated. The characterization studies were carried out by using the Fourier Transform Infrared Spectroscopy (FTIR), X-Ray Diffraction (XRD) analysis and Scanning Electron Microscopy (SEM). HA powder was successfully synthesized with crystallite and particle sizes in the range of 8-47 nm and 250-550 nm respectively. It was observed from this study that the increase of milling rotational speed had increased the phase purity of EHA samples. Furthermore, the higher heating temperature of HA samples resulted in higher degree of crystallinity of HA and the appearance of β-tricalcium phosphate (β-TCP) as secondary phase.

  3. Dual Role of a Ricinoleic Acid Derivative in the Aqueous Synthesis of Silver Nanoparticles

    Directory of Open Access Journals (Sweden)

    Isadora Dantas Costa

    2017-01-01

    Full Text Available We show that sodium 9,10-epoxy-12-hydroxytetradecanoate (SEAR, an epoxidized derivative of ricinoleic acid, simultaneously functioned as reducing and stabilizing agents in the synthesis of silver nanoparticles in alkaline aqueous medium. The advantage of using SEAR is its biodegradability and nontoxicity, which are important characteristics for mitigation of environmental impact upon discharge of nanoparticles into terrestrial and aquatic ecosystems. The SEAR concentration was found to impact considerably the size distribution of silver nanoparticles (AgNPs. A concentration below the SEAR critical micelle concentration (CMC generated 23 nm sized AgNPs with 10 nm standard deviation, while 50 nm sized AgNPs (σ=21 nm were obtained at a concentration above the SEAR CMC. FTIR analysis revealed that the carboxylate that constitutes the SEAR hydrophilic head binds directly to the AgNPs surface promoting stabilization in solution. Finally, AgNPs turned into Ag2S upon contact with wastewater samples from Wastewater Treatment Plant at Federal University of Rio Grande do Norte (UFRN, Brazil, which is an interesting result, since Ag2S is more environmentally friendly than pure AgNPs.

  4. Synthesis, structural characterization and quantum chemical studies of silicon-containing benzoic acid derivatives

    Science.gov (United States)

    Zaltariov, Mirela-Fernanda; Cojocaru, Corneliu; Shova, Sergiu; Sacarescu, Liviu; Cazacu, Maria

    2016-09-01

    The present paper is concerned with the synthesis and molecular structure investigation of two new benzoic acid derivatives having trimethylsilyl tails, 4-((trimethylsilyl)methoxy) and 4-(3-(trimethylsilyl)propoxy)benzoic acids. The structures of the novel compounds have been confirmed by X-ray crystallography, Fourier-transform infrared spectroscopy (FTIR) and nuclear magnetic resonance (1H and 13C NMR). The theoretical studies of molecules were conducted by using the quantum chemical methods, such as Density Functional Theory (DFT B3LYP/6-31 + G**), Hartree-Fock (HF/6-31 + G**) and semiempirical computations (PM3, PM6 and PM7). The optimized molecular geometries have been found to be in good agreement with experimental structures resulted from the X-ray diffraction. The maximum electronic absorption bands observed at 272-287 nm (UV-vis spectra) have been assigned to π → π* transitions, which were in reasonable agreement with the time dependent density functional theory (TD-DFT) calculations. The computed vibrational frequencies by DFT method were assigned and compared with the experimental FTIR spectra. The mapped electrostatic potentials revealed the reactive sites, which corroborated the observation of the dimer supramolecular structures formed in the crystals by hydrogen-bonding. The energies of frontier molecular orbitals (HOMO and LUMO), energy gap, dipole moment and molecular descriptors for the new compounds were calculated and discussed.

  5. New anthrarobin acyl derivatives as butyrylcholinesterase inhibitors: synthesis, in vitro and in silico studies

    Directory of Open Access Journals (Sweden)

    Mehreen Lateef

    2017-07-01

    Full Text Available To treat Alzheimer's disease (AD, the available candidates are effective only against mild AD or have side effects. So, a study was planned to synthesis new candidates that may have good potential to treat AD. A series of new anthrarobin acyl derivatives (2–8 were synthesized by the reaction of anthrarobin (1 and acetic anhydride/acyl chlorides. The product were characterized by 1H NMR and EI-MS, and evaluated for butyrylcholinesterase (BuChE inhibition activity. Compounds 5 and 4 showed notable BuChE inhibitory potential with IC50 5.3 ± 1.23 and 17.2 ± 0.47 μM, respectively when compared with the standard eserine (IC50 7.8 ± 0.27 μM, compound 5 showed potent BuChE inhibition potential than the standard eserine. The active compounds 5 and 4 have acyl groups at 2-OH and 10-OH positions which may be responsible for inhibitory potential as this orientation is absent in other products. In silico studies of 5 and 4 products revealed the high inhibitory potential due to stable binding of ligand with the BuChE active sites with docking energy score −18.8779 kcal/mol and −23.1159 kcal/mol, respectively. Subsequently, compound 5 that have potent BuChE inhibitory activity could be the potential candidate for drug development for Alzheimer’s disease.

  6. One-Pot Multicomponent Synthesis of Thiourea Derivatives in Cyclotriphosphazenes Moieties

    Directory of Open Access Journals (Sweden)

    Zainab Ngaini

    2017-01-01

    Full Text Available In this study, hexasubstituted thiourea was carried out via reaction of isothiocyanato cyclophosphazene intermediates with a series of aromatics amines and amino acids in a one-pot reaction system. The reaction was not as straightforward as typical thiourea synthesis. Six unexpected thiourea derivatives 3a–f were formed in the presence of cyclotriphosphazene moieties in good yields (53–82%. The structures of 3a–f were characterized by elemental analysis and FTIR, 1H, 13C, and 31P NMR spectroscopies. The occurrence of reverse thioureas formation in a one-pot reaction system is discussed. The possible binding interaction of the synthesised thiourea 3a-b in comparison to the predicted phenyl thiourea 5a-b and the targeted 4a with enzyme enoyl ACP reductase (FabI is also discussed. Molecular docking of the targeted hexasubstituted thiourea 4a is able to give higher binding affinity of −7.5 kcal/mol compared to 5a-b (−5.9 kcal/mol and −6.3 kcal/mol and thiourea 3a-b (−4.5 kcal/mol and −4.7 Kcal/mol.

  7. Design, Synthesis, and Biological Evaluation of Vanillin Hydroxamic Acid Derivatives as Novel Peptide Deformylase Inhibitors.

    Science.gov (United States)

    Gao, Jian; Qiu, Shengzhi; Liang, Li; Hao, Zhixiang; Zhou, Qianqian; Wang, Fanfan; Mou, Jie; Lin, Qisi

    2018-01-01

    Infectious disease is increasingly hampering human health, which challenge the discovery of new antibacterial target. Peptide deformylase (PDF), a metalloenzyme responsible for catalyzing the removal of the N-formyl group from nascent proteins, was considered as an important target in antibacterial drug discovery. Reported here are the design, synthesis and biological evaluation of vanillin hydroxamic acid derivatives. Analysis of the structure-activity relationships lead to the discovery of compound 8, which exhibits promising antibacterial activity against Escherichia coli, Staphylococcus aureus, Aspergillus oryzae, and Aspergillus foetidus with the MIC value of 0.32 µg/ml, 0.32 µg/ml, 0.16 µg/ml and 0.16 µg/ml, respectively. Furthermore, molecular docking study was applied to elucidate binding interaction between compound 8 and PDF, which indicate that compound 8 not only shares the same binding pocket with actinonin, but also has a similar binding pattern. In silico pharmacokinetic and toxicity prediction studies also suggested that compound 8 has a relatively high drug score of 0.80, and has no risk of toxicity. Compound 8 might represent a promising scaffold for the further development of novel antibacterial drugs. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  8. In Silico Screening and Designing Synthesis of Cinchona Alkaloids Derivatives as Potential Anticancer

    Directory of Open Access Journals (Sweden)

    Muhammad Hanafi

    2017-06-01

    Full Text Available P-glycoprotein (P-gp resistance in cancer cells decreases intracellular accumulation of various anticancer drugs. This multidrug resistance (MDR protein can be modulated by a number of non-cytotoxic drugs. We have screened 30 chincona alkaloids derivatives as a potent P-gp inhibitor agent in silico. Hereby, we report the highest potential inhibitions of P-gp is Cinchonidine isobutanoate through molecular docking approach. with affinity energy -8.6 kcal/mol and inhibition constant, Ki is 4.89 x 10-7 M. Cinchonidine isobutanoate is also known has molecular weight below 500, Log P value 3.5, which is indicated violation free of Lipinski`s rule of five. Thus, Cinchonidine isobutanoate is the most potent compound as anticancer compare to other Cinchona alkaloids. Ultimately, we design Cinchonidine isobutanoate for further lead synthesis by using DBSA, act as a combined Brønsted acid-surfactant-catalyst (BASC to obtain high concentration of organic product by forming micellar aggregates which is very powerful catalytic application in water environment.

  9. Synthesis of naturally-derived macromolecules through simplified electrochemically mediated ATRP

    Directory of Open Access Journals (Sweden)

    Paweł Chmielarz

    2017-11-01

    Full Text Available The flavonoid-based macroinitiator was received for the first time by the transesterification reaction of quercetin with 2-bromoisobutyryl bromide. In accordance with the “grafting from” strategy, a naturally-occurring star-like polymer with a polar 3,3',4',5,6-pentahydroxyflavone core and hydrophobic poly(tert-butyl acrylate (PtBA side arms was synthesized via a simplified electrochemically mediated ATRP (seATRP, utilizing only 78 ppm by weight (wt of a catalytic CuII complex. To demonstrate the possibility of temporal control, seATRP was carried out utilizing a multiple-step potential electrolysis. The rate of the polymerizations was well-controlled by applying optimal potential values during preparative electrolysis to prevent the possibility of intermolecular coupling of the growing polymer arms. This appears to be the first report using on-demand seATRP for the synthesis of QC-(PtBA-Br5 pseudo-star polymers. The naturally-derived macromolecules showed narrow MWDs (Đ = 1.08–1.11. 1H NMR spectral results confirm the formation of quercetin-based polymers. These new flavonoid-based polymer materials may find applications as antifouling coatings and drug delivery systems.

  10. Synthesis, Characterization and Antimicrobial Evaluation of some Thiazole-Derived Carbamates, Semicarbazones, Amides and Carboxamide

    International Nuclear Information System (INIS)

    Balawi, N.A.A.; ALShaikh, M.A.A.; Alafeefy, A.M.; Khan, K.M.

    2016-01-01

    This study comprises the synthesis and characterization of twenty thiazole-derived carbamates (3a-e), N-substituted amides (8a-h) and carboxamide (10) from 2-aminothiazoles (1a, b) via nucleophilic substitution reactions with activated carbonyl compounds including, chloroformates (2a-d), acid chlorides (7a-e) and glutaric anhydride (9), respectively. Sequential hydrazinolysis of carbamate (3e) and condensation with a variety of aldehydes and ketones (5a d) afforded the corresponding semicarbazones (6a-d). Some selected synthesized compounds were subjected to in vitro antimicrobial evaluation against common pathogens including, Gram+ve bacteria Bacillus subtilis (NRRL B-543) and Staphylococcus aureus, Gram-ve bacteria Escherichia coli (NRRLB-21), yeasts-Candida albicans (NRRLY-477) and Saccharomyces cercvisiae (NRRL Y-567) and fungs Asperigillus niger (NRRL 599). Screening results revealed that most of the tested compounds possess good antimicrobial activity compared to standard drugs. The highest inhibitory effects against Gram-ve Escherichia coli, Gram+ve Staphylococcus aureus, yeast Candida albicans and fungus Aspergillus niger was displayed by amide (8g) bearing the thiophene moiety. (author)

  11. Prebiotic Synthesis of Autocatalytic Products From Formaldehyde-Derived Sugars as the Carbon and Energy Source

    Science.gov (United States)

    Weber, Arthur L.

    2003-01-01

    Our research objective is to understand and model the chemical processes on the primitive Earth that generated the first autocatalytic molecules and microstructures involved in the origin of life. Our approach involves: (a) investigation of a model origin-of-life process named the Sugar Model that is based on the reaction of formaldehyde- derived sugars (trioses and tetroses) with ammonia, and (b) elucidation of the constraints imposed on the chemistry of the origin of life by the fixed energies and rates of C,H,O-organic reactions under mild aqueous conditions. Recently, we demonstrated that under mild aqueous conditions the Sugar Model process yields autocatalytic products, and generates organic micropherules (2-20 micron dia.) that exhibit budding, size uniformity, and chain formation. We also discovered that the sugar substrates of the Sugar Model are capable of reducing nitrite to ammonia under mild aqueous conditions. In addition studies done in collaboration with Sandra Pizzarrello (Arizona State University) revealed that chiral amino acids (including meteoritic isovaline) catalyze both the synthesis and specific handedness of chiral sugars. Our systematic survey of the energies and rates of reactions of C,H,O-organic substrates under mild aqueous conditions revealed several general principles (rules) that govern the direction and rate of organic reactions. These reactivity principles constrain the structure of chemical pathways used in the origin of life, and in modern and primitive metabolism.

  12. Design, synthesis, α-glucosidase inhibitory activity, molecular docking and QSAR studies of benzimidazole derivatives

    Science.gov (United States)

    Dinparast, Leila; Valizadeh, Hassan; Bahadori, Mir Babak; Soltani, Somaieh; Asghari, Behvar; Rashidi, Mohammad-Reza

    2016-06-01

    In this study the green, one-pot, solvent-free and selective synthesis of benzimidazole derivatives is reported. The reactions were catalyzed by ZnO/MgO containing ZnO nanoparticles as a highly effective, non-toxic and environmentally friendly catalyst. The structure of synthesized benzimidazoles was characterized using spectroscopic technics (FT-IR, 1HNMR, 13CNMR). Synthesized compounds were evaluated for their α-glucosidase inhibitory potential. Compounds 3c, 3e, 3l and 4n were potent inhibitors with IC50 values ranging from 60.7 to 168.4 μM. In silico studies were performed to explore the binding modes and interactions between enzyme and synthesized benzimidazoles. Developed linear QSAR model based on density and molecular weight could predict bioactivity of newly synthesized compounds well. Molecular docking studies revealed the availability of some hydrophobic interactions. In addition, the bioactivity of most potent compounds had good correlation with estimated free energy of binding (ΔGbinding) which was calculated according to docked best conformations.

  13. Synthesis of Galactosyl Mannitol Derivative Using β-Galactosidase from Kluyveromyces lactis

    Directory of Open Access Journals (Sweden)

    Klewicki Robert

    2017-03-01

    Full Text Available The purpose of the study was to identify the influence of reactive mixture concentration (23–48 g/100 mL, pH (6.5–9.0, presence of NaCl (0.05–0.25 mol/L and enzyme dose (2850–28,500 LAU/100 g of lactose on the synthesis of galactosyl mannitol derivative using β-galactosidase from Kluyveromyces lactis. The use of the enzyme dose ranging from 2850 to 11,400 LAU/100 g lactose allowed obtaining gal-mannitol at the level of 21.8% total saccharides; higher doses intensified product decomposition. An increase in the concentration of the reactive mixture had a positive impact on the quantity of gal-mannitol obtained every single time, i.e. 4.39 g were obtained from 100 mL of a 23 g/100 mL solution and over 10 g were obtained from a 48 g/100 mL solution. A relatively low increase in product quantity (by ca. 5% occurred after the pH was increased from 6.5 to 9.0. The use of NaCl rendered better results. An increase in the maximum content of gal-mannitol in the total sugar by 12.8% was observed at the concentration of 0.25 mol/L.

  14. Quantum Chemical and Experimental Studies on the Mechanism of Alkylation of β-Dicarbonyl Compounds. The Synthesis of Five and Six Membered Heterocyclic Spiro Derivatives

    Directory of Open Access Journals (Sweden)

    Ali Hüseyinli

    2004-11-01

    Full Text Available The alkylation of β-dicarbonyl compounds in a K2CO3/DMSO system wasfound to afford O- and C-alkylated derivatives, depending on the type of the β-dicarbonylcompound involved. The alkyl derivatives obtained were used in the synthesis of some newspiro barbituric acid derivatives. Quantum chemical calculations were carried out toelucidate the reaction mechanisms for some typical synthesis.

  15. Novel polymer derived ceramic-high temperature heat flux sensor for gas turbine environment

    International Nuclear Information System (INIS)

    Nagaiah, N R; Kapat, J S; An, L; Chow, L

    2006-01-01

    This paper attempts to prove the feasibility of a novel High Temperature Heat Flux (HTHF) sensor for gas turbine environment. Based on the latest improvement in a new type of Polymer-Derived Ceramic (PDC) material, the authors present the design and development of a HTHF sensor based on PDC material, and show that such a sensor is indeed feasible. The PDC-HTHF sensor is fabricated using newly developed polymer derived SiCN, whose conductivity is controlled by proper composition and treatment condition. Direct measurements and characterization of the relevant material properties are presented. Electrical conductivity can be varied from 0 (insulator) to 100 (ohm.cm) -1 ; in addition a value of 4000 ppm/ 0 C (at 600 K) is obtained for temperature coefficient of resistance. This novel sensor is found to perform quite satisfactorily at about 1400 0 C for long term as compared to conventional heat flux sensors available commercially. This type of PDC-HTHF sensor can be used in harsh environments due to its high temperature resistance and resistance to oxidation. This paper also discusses lithography as a microfabrication technique to manufacture the proposed PDC-HTHF sensor. In our current design, the sensor dimensions are 2.5mm in diameter and 250 μm thickness

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

    International Nuclear Information System (INIS)

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

    2007-01-01

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

  17. Economic evaluation of the solar thermal co-production of zinc, synthesis gas, and hydrogen

    Energy Technology Data Exchange (ETDEWEB)

    Steinfeld, A [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Spiewak, I [EC Joint Research Centre (Spain)

    1999-08-01

    The use of concentrated solar energy for co-producing Zn and synthesis gas from Zn O and natural gas upgrades the calorific value of the initial reactants by 39% and, when compared to the traditional carbothermic reduction of Zn O, has the potential of reducing CO{sub 2} emissions by up to 78%. An economic assessment for an industrial thermochemical plant, 30 to 51 MW solar input, indicates that the cost of solar production of zinc ranges between 89-133 $/t (excluding the cost of Zn O feed and credit for pollution abatement), and thus might be competitive with conventional fossil-fuel-based processes at current fuel prices. The cost of solar H{sub 2}, produced by splitting water with zinc, is estimated to be in the range 0.10-0.14 $/kWh, and it is a favorable long term prospect once the cost of energy will account for the environmental externalities from fossil fuel burning such as the costs for CO{sub 2} mitigation and pollution abatement. (author) 1 fig., 2 tabs., 5 refs.

  18. CdSe Nanoparticles with Clean Surfaces: Gas Phase Synthesis and Optical Properties

    Directory of Open Access Journals (Sweden)

    Zhang Hongwei

    2015-01-01

    Full Text Available CdSe nanoparticles (NPs were generated in gas phase with a magnetron plasma gas aggregation cluster beam source. Coagulation-free CdSe nanocrystals with very clean particle surface and interface, as well as a fairly uniform spatial distribution were obtained. The deposited NPs have a good dispersity with a mean diameter of about 4.8nm. A strong photoluminescence band corresponding to the near- band-edge transition of the CdSe NPs was observed. The CdSe NP films show a significant photoconductance induced by laser irradiation. With an applied bias voltage of 10V, the photo- induced current can be as high as 0.4mA under 0.01mW/mm2 405nm laser illumination. Our approach offers an alternative method for CdSe NP synthesis, which has the advantages such as high purity, good process and product control, as well as mass production, as compared to the existing methods.

  19. Synthesis and gas-sensing characteristics of α-Fe2O3 hollow balls

    Directory of Open Access Journals (Sweden)

    Chu Manh Hung

    2016-03-01

    Full Text Available The synthesis of porous metal-oxide semiconductors for gas-sensing application is attracting increased interest. In this study, α-Fe2O3 hollow balls were synthesized using an inexpensive, scalable, and template-free hydrothermal method. The gas-sensing characteristics of the semiconductors were systematically investigated. Material characterization by XRD, SEM, HRTEM, and EDS reveals that single-phase α-Fe2O3 hollow balls with an average diameter of 1.5 μm were obtained. The hollow balls were formed by self assembly of α-Fe2O3 nanoparticles with an average diameter of 100 nm. The hollow structure and nanopores between the nanoparticles resulted in the significantly high response of the α-Fe2O3 hollow balls to ethanol at working temperatures ranging from 250 °C to 450 °C. The sensor also showed good selectivity over other gases, such as CO and NH3 promising significant application.

  20. Synthesis, characterization and liquefied petroleum gas (LPG) sensing properties of WO3 nano-particles

    Science.gov (United States)

    Singh, Subhash; Majumder, S. B.

    2018-05-01

    Metal oxide sensors, such as ZnO, SnO2, and WO3 etc. have been utilized for several decades for low-costd etection of combustible and toxic gases. In the present work tungsten oxide (WO3) nanoparticles have been prepared by using an economic wet chemical synthesis route. To understand the phase formation behavior of the synthesized powders, X-ray diffraction analysis has been performed. The microstructure evolution of the synthesized powders was characterized by field-emission scanning electron microscopy (FESEM), and transmission electron microscopy (TEM). The calcined phase pure WO3 nanoparticles are investigated in terms of LPG gas sensing properties. The gas sensing measurements has been done in two different mode of operation (namely static and dynamic measurements). The degree of oxygen deficiency in the WO3 sensor also affected the sensor properties and the optimum oxygen content of WO3 was necessary to get high sensitivity for LPG. The WO3 sensor shows the excellent sensor properties for LPG at the operating temperature of 250°C.

  1. Direct synthesis of iso-butane from synthesis gas or CO2 over CuZnZrAl/Pd-β hybrid catalyst

    Directory of Open Access Journals (Sweden)

    Congming Li

    2017-12-01

    Full Text Available The effect of various factors on the catalytic performance of iso-butane formation over CuZnZrAl/Pd-β hybrid catalyst via synthesis gas or CO2 hydrogenation has been deeply investigated in this work. It was interesting to note that the iso-butane/n-butane ratio value was much higher than that of thermodynamic equilibrium (about 1/1, whose value was directly related to the reaction condition using this hybrid catalyst. In order to further clearly clarify this finding, various experimental reaction factors were selected to investigate the formation of iso-butane. The results revealed that increasing temperature, H2/COx, CO2/COx, and/or Pd loading possessed an inhibiting effect on the iso-butane yield. High selectivity of iso-butane could be achieved by increasing the reaction pressure, W/F and the weight ratio of CuZnZrAl methanol catalyst to Pd-β catalyst. It is also noted that the addition of water seriously suppressed the reaction activity, resulting in the low ratio of iso-butane/n-butane. A possible reaction route was elucidated based on the latest results. This might shed light on the development of a high efficient catalyst for iso-butane production from synthesis gas or CO2 hydrogenation. Keywords: Iso-butane, Synthesis gas, CO2, CuZnZrAl/Pd-β hybrid catalyst

  2. Synthesis of new annulated pyrano[2,3-d]pyrimidine derivatives using organo catalyst (DABCO in aqueous media

    Directory of Open Access Journals (Sweden)

    Ajmal R. Bhat

    2017-01-01

    Full Text Available A selective method for the synthesis of annulated pyrano[2,3-d]pyrimidines has been developed. It was shown that base catalysis is more efficient in this reaction, rather than acid catalysis as it is believed that 1,4-diazabicyclo[2.2.2]octane (DABCO is N-type base catalyst used for the synthesis of pyrano[2,3-d]pyramidine derivatives via one-pot three component condensation reactions of various aromatic aldehydes, active methylene compounds and barbituric acid in aqueous ethanol carried at normal temperature. The potential application of DABCO in organic synthesis increasing rapidly because of its reaction simplicity, less pollution, and minimum reaction time, high yields of the biological active products, uses less toxic solvents and low cost chemicals.

  3. Synthesis Gas Purification Purification des gaz de synthèse

    Directory of Open Access Journals (Sweden)

    Chiche D.

    2013-10-01

    Full Text Available Fischer-Tropsch (FT based B-XTL processes are attractive alternatives for future energy production. These processes aim at converting lignocellulosic biomass possibly in co-processing with petcoke, coal, or vacuum residues into synthetic biofuels. A gasification step converts the feed into a synthesis gas (CO and H2 mixture , which undergoes the Fischer-Tropsch reaction after H2/CO ratio adjustment and CO2 removal. However synthesis gas also contains various impurities that must be removed in order to prevent Fischer-Tropsch catalyst poisoning. Due to the large feedstocks variety that can be processed, significant variations of the composition of the synthesis gas are expected. Especially, this affects the nature of the impurities that are present (element, speciation, as well as their relative contents. Moreover, due to high FT catalyst sensitivity, severe syngas specifications regarding its purity are required. For these reasons, synthesis gas purification constitutes a major challenge for the development of B-XTL processes. In this article, we focus on these major hurdles that have to be overcome. The different kinds of syngas impurities are presented. The influence of the nature of feedstocks, gasification technology and operating conditions on the type and content of impurities is discussed. Highlight is given on the fate of sulfur compounds, nitrogen compounds, halides, transition and heavy metals. Main synthesis gas purification technologies (based on adsorption, absorption, catalytic reactions, etc. are finally described, as well as the related challenges. Les procédés de synthèse de biocarburants par voie Fischer-Tropsch (FT, voies B-XTL, représentent des alternatives prometteuses pour la production d’énergie. Ces procédés permettent la conversion en carburants de synthèse de biomasse lignocellulosique, éventuellement mise en oeuvre en mélange avec des charges fossiles telles que petcoke, charbons ou résidus sous vide. Pour

  4. Flash pyrolysis at high temperature of ligno-cellulosic biomass and its components - production of synthesis gas

    International Nuclear Information System (INIS)

    Couhert, C.

    2007-11-01

    Pyrolysis is the first stage of any thermal treatment of biomass and governs the formation of synthesis gas for the production of electricity, hydrogen or liquid fuels. The objective of this work is to establish a link between the composition of a biomass and its pyrolysis gas. We study experimental flash pyrolysis and fix the conditions in which quantities of gas are maximal, while aiming at a regime without heat and mass transfer limitations (particles about 100 μm): temperature of 950 C and residence time of about 2 s. Then we try to predict gas yields of any biomass according to its composition, applicable in this situation where thermodynamic equilibrium is not reached. We show that an additivity law does not allow correlating gas yields of a biomass with fractions of cellulose, hemi-cellulose and lignin contained in this biomass. Several explanations are suggested and examined: difference of pyrolytic behaviour of the same compound according to the biomass from which it is extracted, interactions between compounds and influence of mineral matter. With the aim of industrial application, we study pyrolysis of millimetric and centimetric size particles, and make a numerical simulation of the reactions of pyrolysis gases reforming. This simulation shows that the choice of biomass affects the quantities of synthesis gas obtained. (author)

  5. Synthesis and characterization of mixed ligand Cu(II) complexes of salicylic acid derivatives with 2-aminobenzotiyazol derivatives

    OpenAIRE

    İlkimen, Halil; Yenikaya, Cengiz

    2018-01-01

    In thisstudy, mixed ligand transitionmetal complexes of Cu(II)have been prepared between salicylic acid derivatives [salicylic acid (H2sal) or acetylsalicylic acid (Hasal)] and 2-aminobenzothiazole derivatives[2-aminobenzothiazole (abt) or 2-amino-6-chlorobenzothiazole (Clabt) or2-amino-6-methylbenzothiazole (Meabt)]. The structures of amorphous metalcomplexes have been proposed by evaluating the data obtained from elementalanalysis, ICP-OES, FT-IR, UV-Vis, thermal analysis, magnetic suscepti...

  6. Ultrasound-Promoted One-Pot, Four-Component Synthesis of Pyridin-2(1H-One Derivatives

    Directory of Open Access Journals (Sweden)

    Jinming Yang

    2013-11-01

    Full Text Available An efficient one-pot synthesis of 1,6-diamino-2-oxo-1,2,3,4-tetrahydro- pyridine-3,5-dicarbonitrile derivatives by four-component piperidine-catalyzed reactions of a ketone, malononitrile, ethyl cyanoacetate and hydrazine hydrate under ultrasound irradiation is described. This method provides several advantages such as shorter reaction times, excellent yields, and a simple workup procedure.

  7. Analysis of naphthenic acid mixtures as pentafluorobenzyl derivatives by gas chromatography-electron impact mass spectrometry.

    Science.gov (United States)

    Gutierrez-Villagomez, Juan Manuel; Vázquez-Martínez, Juan; Ramírez-Chávez, Enrique; Molina-Torres, Jorge; Trudeau, Vance L

    2017-01-01

    In this study, we report for the first time the efficiency of pentafluorobenzyl bromide (PFBBr) for naphthenic acid (NA) mixtures derivatization, and the comparison in the optimal conditions to the most common NAs derivatization reagents, BF 3 /MeOH and N-(t-butyldimethylsilyl)-N-methyltrifluoroacetamide (MTBSTFA). Naphthenic acids are carboxylic acid mixtures of petrochemical origin. These compounds are important for the oil industry because of their corrosive properties, which can damage oil distillation infrastructure. Moreover, NAs are commercially used in a wide range of products such as paint and ink driers, wood and fabric preservatives, fuel additives, emulsifiers, and surfactants. Naphthenic acids have also been found in sediments after major oils spills in the United States and South Korea. Furthermore, the toxicity of the oil sands process-affected water (OSPW), product of the oil sands extraction activities in Canada's oil sands, has largely been attributed to NAs. One of the main challenges for the chromatographic analysis of these mixtures is the resolution of the components. The derivatization optimization was achieved using surface response analysis with molar ratio and time as factors for derivatization signal yield. After gas chromatography-electron impact mass spectrometry (GC/EIMS) analysis of a mixture of NA standards, it was found that the signal produced by PFB-derivatives was 2.3 and 1.4 times higher than the signal produced by methylated and MTBS-derivatives, respectively. The pentafluorobenzyl derivatives have a characteristic fragment ion at 181m/z that is diagnostic for the differentiation of carboxylic and non-carboxylic acid components within mixtures. In the analysis of a Sigma and a Merichem derivatized oil extract NA mixtures, it was found that some peaks lack the characteristic fragment ion; therefore they are not carboxylic acids. Open column chromatography was used to obtain a hexane and a methanol fraction of the Sigma and

  8. Synthesis and Gas Transport Properties of Hyperbranched Polyimide–Silica Hybrid/Composite Membranes

    Directory of Open Access Journals (Sweden)

    Masako Miki

    2013-12-01

    Full Text Available Hyperbranched polyimide–silica hybrids (HBPI–silica HBDs and hyperbranched polyimide–silica composites (HBPI–silica CPTs were prepared, and their general and gas transport properties were investigated to clarify the effect of silica sources and preparation methods. HBPI–silica HBDs and HBPI–silica CPTs were synthesized by two-step polymerization of A2 + B3 monomer system via polyamic acid as precursor, followed by hybridizing or blending silica sources. Silica components were incorporated by the sol-gel reaction with tetramethoxysilane (TMOS or the addition of colloidal silica. In HBPI-silica HBDs, the aggregation of silica components is controlled because of the high affinity of HBPI and silica caused by the formation of covalent bonds between HBPI and silica. Consequently, HBPI-silica HBDs had good film formability, transparency, and mechanical properties compared with HBPI-silica CPTs. HBPI-silica HBD and CPT membranes prepared via the sol-gel reaction with TMOS showed specific gas permeabilities and permselectivities for CO2/CH4 separation, that is, both CO2 permeability and CO2/CH4 selectivity increased with increasing silica content. This result suggests that gas transport can occur through a molecular sieving effect of the porous silica network derived from the sol-gel reaction and/or through the narrow interfacial region between the silica networks and the organic matrix.

  9. Synthesis of New 3-(2-Chloroquinolin-3-yl)-5-Phenylisoxazole Derivatives via Click-Chemistry Approach

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez-Galleguillos, Carlos; Saavedra, Luis A.; Gutierrez, Margarita [Laboratorio de Sintesis Organica, Instituto de Quimica de Recursos Naturales, Universidad de Talca (Chile)

    2014-02-15

    Herein, we report the synthesis of new substituted 3-(2-chloroquinolin-3-yl)-5-phenylisoxazole (3a-j) by click chemistry in good to moderate yields. This approach is based on the regioselective copper(I)-catalyzed cycloaddition between different nitrile oxides derived from 2-chloroquinoline- 3-carbaldehyde (2a-j) and phenylacetylene. Finally these derivatives were screened for their antibacterial evaluation in vitro against three Gram-negative clinical bacteria: Escherichia coli, Pseudomonas aeruginosa and Acinetobacter baumannii using standard methods. (author)

  10. Efficient synthesis of sulfonamide derivatives on solid supports catalyzed using solvent-free and microwave-assisted methods

    Energy Technology Data Exchange (ETDEWEB)

    Camargo-Ordonez, Argelia; Moreno-Reyes, Christian; Olazaran-Santibanez, Fabian; Martinez-Hernandez, Sheila; Bocanegra-Garcia, Virgilio; Rivera, Gildardo [Universidad Autonoma de Tamaulipas, Reynosa (Mexico). Dep. de Farmacia y Quimica Medicinal

    2011-07-01

    In this work we report the synthesis of sulfonamide derivatives using a conventional procedure and with solid supports, such as silica gel, florisil, alumina, 4A molecular sieves, montmorillonite KSF, and montmorillonite K10 using solvent-free and microwave-assisted methods. Our results show that solid supports have a catalytic activity in the formation of sulfonamide derivatives. We found that florisil, montmorillonite KSF, and K10 could be used as inexpensive alternative catalysts that are easily separated from the reaction media. Additionally, solvent-free and microwave-assisted methods were more efficient in reducing reaction time and in increasing yield. (author)

  11. Efficient synthesis of sulfonamide derivatives on solid supports catalyzed using solvent-free and microwave-assisted methods

    International Nuclear Information System (INIS)

    Camargo-Ordonez, Argelia; Moreno-Reyes, Christian; Olazaran-Santibanez, Fabian; Martinez-Hernandez, Sheila; Bocanegra-Garcia, Virgilio; Rivera, Gildardo

    2011-01-01

    In this work we report the synthesis of sulfonamide derivatives using a conventional procedure and with solid supports, such as silica gel, florisil, alumina, 4A molecular sieves, montmorillonite KSF, and montmorillonite K10 using solvent-free and microwave-assisted methods. Our results show that solid supports have a catalytic activity in the formation of sulfonamide derivatives. We found that florisil, montmorillonite KSF, and K10 could be used as inexpensive alternative catalysts that are easily separated from the reaction media. Additionally, solvent-free and microwave-assisted methods were more efficient in reducing reaction time and in increasing yield. (author)

  12. Synthesis of New 3-(2-Chloroquinolin-3-yl)-5-Phenylisoxazole Derivatives via Click-Chemistry Approach

    International Nuclear Information System (INIS)

    Fernández-Galleguillos, Carlos; Saavedra, Luis A.; Gutierrez, Margarita

    2014-01-01

    Herein, we report the synthesis of new substituted 3-(2-chloroquinolin-3-yl)-5-phenylisoxazole (3a-j) by click chemistry in good to moderate yields. This approach is based on the regioselective copper(I)-catalyzed cycloaddition between different nitrile oxides derived from 2-chloroquinoline- 3-carbaldehyde (2a-j) and phenylacetylene. Finally these derivatives were screened for their antibacterial evaluation in vitro against three Gram-negative clinical bacteria: Escherichia coli, Pseudomonas aeruginosa and Acinetobacter baumannii using standard methods. (author)

  13. Ultrasound mediated, iodine catalyzed green synthesis of novel 2-amino-3-cyano-4H-pyran derivatives.

    Science.gov (United States)

    Tabassum, Sumaiya; Govindaraju, Santhosh; Khan, Riyaz-ur-Rahaman; Pasha, Mohamed Afzal

    2015-05-01

    An efficient synthesis of a novel series of twelve substituted 2-amino-3-cyano-4H-pyran derivatives was achieved by a one-pot three-component cyclocondensation reaction of heteroaryl aldehydes, malononitrile and active methylene compounds catalyzed by iodine in aqueous medium under ultrasound irradiation. In comparison with conventional methods, our protocol is convenient and offers several advantages, such as shorter reaction time, higher yields, milder conditions and environmental friendliness. We have herein successfully demonstrated the synergistic outcome of multi-component reaction (MCR) and sonication to offer a facile route for the design of these derivatives. Copyright © 2014 Elsevier B.V. All rights reserved.

  14. One-pot green synthesis of zinc oxide nano rice and its application as sonocatalyst for degradation of organic dye and synthesis of 2-benzimidazole derivatives

    Science.gov (United States)

    Paul, Bappi; Vadivel, Sethumathavan; Dhar, Siddhartha Sankar; Debbarma, Shyama; Kumaravel, M.

    2017-05-01

    In this paper, we report novel and green approach for one-pot biosynthesis of zinc oxide (ZnO) nanoparticles (NPs). Highly stable and hexagonal phase ZnO nanoparticles were synthesized using seeds extract from the tender pods of Parkia roxburghii and characterized by XRD, FT-IR, EDX, TEM, and N2 adsorption-desorption (BET) studies. The present method of synthesis of ZnO NPs is very efficient and cost effective. The powder XRD pattern furnished evidence for the formation of hexagonal close packing structure of ZnO NPs having average crystallite size 25.6 nm. The TEM image reveals rice shapes ZnO NPs are with an average diameter of 40-60 nm. The as-synthesized ZnO NPs has proved to be an excellent sonocatalysts for degradation of organic dye and synthesis of 2-benzimidazole derivatives.

  15. Stereoselective synthesis, X-ray analysis, computational studies and biological evaluation of new thiazole derivatives as potential anticancer agents.

    Science.gov (United States)

    Mabkhot, Yahia N; Alharbi, Mohammed M; Al-Showiman, Salim S; Ghabbour, Hazem A; Kheder, Nabila A; Soliman, Saied M; Frey, Wolfgang

    2018-05-11

    The synthesis of new thiazole derivatives is very important because of their diverse biological activities. Also , many drugs containing thiazole ring in their skeletons are available in the market such as Abafungin, Acotiamide, Alagebrium, Amiphenazole, Brecanavir, Carumonam, Cefepime, and Cefmatilen. Ethyl cyanoacetate reacted with phenylisothiocyanate, chloroacetone, in two different basic mediums to afford the thiazole derivative 6, which reacted with dimethylformamide- dimethyl acetal in the presence of DMF to afford the unexpected thiazole derivative 11. The structures of the thiazoles 6 and 11 were optimized using B3LYP/6-31G(d,p) method. The experimentally and theoretically geometric parameters agreed very well. Also, the natural charges at the different atomic sites were predicted. HOMO and LUMO demands were discussed. The anticancer activity of the prepared compounds was evaluated and showed moderate activity. Synthesis of novel thiazole derivatives was done. The structure was established using X-ray and spectral analysis. Optimized molecular structures at the B3LYP/6-31G(d,p) level were investigated. Thiazole derivative 11 has more electropositive S-atom than thiazole 6. The HOMO-LUMO energy gap is lower in the former compared to the latter. The synthesized compounds showed moderate anticancer activity.

  16. cGAS Senses Human Cytomegalovirus and Induces Type I Interferon Responses in Human Monocyte-Derived Cells.

    Directory of Open Access Journals (Sweden)

    Jennifer Paijo

    2016-04-01

    Full Text Available Human cytomegalovirus (HCMV infections of healthy individuals are mostly unnoticed and result in viral latency. However, HCMV can also cause devastating disease, e.g., upon reactivation in immunocompromised patients. Yet, little is known about human immune cell sensing of DNA-encoded HCMV. Recent studies indicated that during viral infection the cyclic GMP/AMP synthase (cGAS senses cytosolic DNA and catalyzes formation of the cyclic di-nucleotide cGAMP, which triggers stimulator of interferon genes (STING and thus induces antiviral type I interferon (IFN-I responses. We found that plasmacytoid dendritic cells (pDC as well as monocyte-derived DC and macrophages constitutively expressed cGAS and STING. HCMV infection further induced cGAS, whereas STING expression was only moderately affected. Although pDC expressed particularly high levels of cGAS, and the cGAS/STING axis was functional down-stream of STING, as indicated by IFN-I induction upon synthetic cGAMP treatment, pDC were not susceptible to HCMV infection and mounted IFN-I responses in a TLR9-dependent manner. Conversely, HCMV infected monocyte-derived cells synthesized abundant cGAMP levels that preceded IFN-I production and that correlated with the extent of infection. CRISPR/Cas9- or siRNA-mediated cGAS ablation in monocytic THP-1 cells and primary monocyte-derived cells, respectively, impeded induction of IFN-I responses following HCMV infection. Thus, cGAS is a key sensor of HCMV for IFN-I induction in primary human monocyte-derived DC and macrophages.

  17. The comparison of physical properties derived from gas and dust in a massive star-forming region

    Energy Technology Data Exchange (ETDEWEB)

    Battersby, Cara; Bally, John; Ginsburg, Adam; Darling, Jeremy [Center for Astrophysics and Space Astronomy, University of Colorado, UCB 389, Boulder, CO 80309 (United States); Dunham, Miranda [Department of Astronomy, Yale University, New Haven, CT 06520 (United States); Longmore, Steve [Astrophysics Research Institute, Liverpool John Moores University, Twelve Quays House, Egerton Wharf, Birkenhead CH41 1LD (United Kingdom)

    2014-05-10

    We explore the relationship between gas and dust in a massive star-forming region by comparing the physical properties derived from each. We compare the temperatures and column densities in a massive star-forming Infrared Dark Cloud (G32.02+0.05), which shows a range of evolutionary states, from quiescent to active. The gas properties were derived using radiative transfer modeling of the (1,1), (2,2), and (4,4) transitions of NH{sub 3} on the Karl G. Jansky Very Large Array, while the dust temperatures and column densities were calculated using cirrus-subtracted, modified blackbody fits to Herschel data. We compare the derived column densities to calculate an NH{sub 3} abundance, χ{sub NH{sub 3}} = 4.6 × 10{sup –8}. In the coldest star-forming region, we find that the measured dust temperatures are lower than the measured gas temperatures (mean and standard deviations T {sub dust,} {sub avg} ∼ 11.6 ± 0.2 K versus T {sub gas,} {sub avg} ∼ 15.2 ± 1.5 K), which may indicate that the gas and dust are not well-coupled in the youngest regions (∼0.5 Myr) or that these observations probe a regime where the dust and/or gas temperature measurements are unreliable. Finally, we calculate millimeter fluxes based on the temperatures and column densities derived from NH{sub 3}, which suggest that millimeter dust continuum observations of massive star-forming regions, such as the Bolocam Galactic Plane Survey or ATLASGAL, can probe hot cores, cold cores, and the dense gas lanes from which they form, and are generally not dominated by the hottest core.

  18. The comparison of physical properties derived from gas and dust in a massive star-forming region

    International Nuclear Information System (INIS)

    Battersby, Cara; Bally, John; Ginsburg, Adam; Darling, Jeremy; Dunham, Miranda; Longmore, Steve

    2014-01-01

    We explore the relationship between gas and dust in a massive star-forming region by comparing the physical properties derived from each. We compare the temperatures and column densities in a massive star-forming Infrared Dark Cloud (G32.02+0.05), which shows a range of evolutionary states, from quiescent to active. The gas properties were derived using radiative transfer modeling of the (1,1), (2,2), and (4,4) transitions of NH 3 on the Karl G. Jansky Very Large Array, while the dust temperatures and column densities were calculated using cirrus-subtracted, modified blackbody fits to Herschel data. We compare the derived column densities to calculate an NH 3 abundance, χ NH 3 = 4.6 × 10 –8 . In the coldest star-forming region, we find that the measured dust temperatures are lower than the measured gas temperatures (mean and standard deviations T dust, avg ∼ 11.6 ± 0.2 K versus T gas, avg ∼ 15.2 ± 1.5 K), which may indicate that the gas and dust are not well-coupled in the youngest regions (∼0.5 Myr) or that these observations probe a regime where the dust and/or gas temperature measurements are unreliable. Finally, we calculate millimeter fluxes based on the temperatures and column densities derived from NH 3 , which suggest that millimeter dust continuum observations of massive star-forming regions, such as the Bolocam Galactic Plane Survey or ATLASGAL, can probe hot cores, cold cores, and the dense gas lanes from which they form, and are generally not dominated by the hottest core.

  19. Synthesis and secretion of platelet-derived growth factor by human breast cancer cell lines

    International Nuclear Information System (INIS)

    Bronzert, D.A.; Pantazis, P.; Antoniades, H.N.; Kasid, A.; Davidson, N.; Dickson, R.B.; Lippman, M.E.

    1987-01-01

    The authors report that human breast cancer cells secrete a growth factor that is biologically and immunologically similar to platelet-derived growth factor (PDGF). Serum-free medium conditioned by estrogen-independent MDA-MB-231 or estrogen-dependent MCF-7 cells contains a mitogenic or competence activity that is capable of inducing incorporation of [ 3 H] thymidine into quiescent Swiss 3T3 cells in the presence of platelet-poor plasma. Like authentic PDGF, the PDGF-like activity produced by breast cancer cells is stable after acid and heat treatment (95 0 C) and inhibited by reducing agents. The mitogenic activity comigrates with a material of ≅30 kDa on NaDodSO 4 /polyacrylamide gels. Immunoprecipitation with PDGF antiserum of proteins from metabolically labeled cell lysates and conditioned medium followed by analysis on nonreducing NaDodSO 4 /polyacrylamide gels identified proteins of 30 and 34 kDa. Upon reduction, the 30- and 34-kDa bands were converted to 15- and 16-kDa bands suggesting that the immunoprecipitated proteins were made up of two disulfide-linked polypeptides similar to PDGF. Hybridization studies with cDNA probes for the A chain PDGF and the B chain of PDGF/SIS identified transcripts for both PDGF chains in the MCF-7 and MDA-MB-231 cells. The data summarized above provide conclusive evidence for the synthesis and hormonally regulated secretion of a PDGF-like mitogen by breast carcinoma cells. Production of a PDGF-like growth factor by breast cancer cell lines may be important in mediating paracrine stimulation of tumor growth

  20. Synthesis, antifungal activity and docking study of 2-amino-4H-benzochromene-3-carbonitrile derivatives

    Science.gov (United States)

    Mirjalili, BiBi Fatemeh; Zamani, Leila; Zomorodian, Kamiar; Khabnadideh, Soghra; Haghighijoo, Zahra; Malakotikhah, Zahra; Ayatollahi Mousavi, Seyyed Amin; Khojasteh, Shaghayegh

    2016-07-01

    Pathogenic fungi are associated with diseases ranging from simple dermatosis to life-threatening infections, particularly in immunocompromised patients. During the past two decades, resistance to established antifungal drugs has increased dramatically and has made it crucial to identify novel antimicrobial compounds. Here, we selected 12 new compounds of 2-amino-4H-benzochromene-3-carbonitrile drivetives (C1-C12) for synthesis by using nano-TiCl4.SiO2 as efficient and green catalyst, then nine of synthetic compounds were evaluated against different species of fungi, positive gram and negative gram of bacteria. Standard and clinical strains of antibiotics sensitive and resistant fungi and bacteria were cultured in appropriate media. Biological activity of the 2-amino-4H-benzochromene-3-carbonitrile derivatives against fungi and bacteries were estimated by the broth micro-dilution method as recommended by clinical and laboratory standard institute (CLSI). In addition minimal fangicidal and bactericial concenteration of the compounds were also determined. Considering our results showed that compound 2-amino-4-(4-methyl benzoate)-4H-benzo[f]chromen-3-carbonitrile (C9) had the most antifungal activity against Aspergillus clavatus, Candida glabarata, Candida dubliniensis, Candida albicans and Candida tropicalis at concentrations ranging from 8 to ≤128 μg/mL. Also compounds 2-amino-4-(3,4-dimethoxyphenyl)-4H-benzo[f]chromen-3-carbonitrile (C4) and 2-amino-4-(4-isopropylphenyl)-4H-benzo[f]chromen-3-carbonitrile (C3) had significant inhibitory activities against Epidermophyton floccosum following 2-amino-4-(4-methylbenzoate)-4H-benzo[f]chromen-3-carbonitrile (C9), respectively. Docking simulation was performed to insert compounds C3, C4 and C9 in to CYP51 active site to determine the probable binding model.

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

    Science.gov (United States)

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

    2017-01-01

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

  2. Synthesis and Investigation Absorption Features of Some Novel Hetarylazo Dyes Derived from Calix[4]resorcinarene

    Directory of Open Access Journals (Sweden)

    İzzet Şener

    2013-12-01

    Full Text Available In this study, several derivatives of amines were diazotized and coupled with 3-aminocrotonitrile to give 2-arylhydrazon-3-ketiminocrotononitrile. The synthesized components were then refluxed with hydrazine hydrate in ethanol to give a series of dyes 5-amino-4-arylazo-3-ethyl-1'H-Pyrazole. The synthesized dyes were diazotised and coupled with resorcinarene, which was obtained from condensation of between resorcinol and acetaldehyde, to give a new synthesis of azo dyes based on resorcinarene. The structures of synthesized dyes based on resorcinarene were characterized by spectral methods. The effect of varying solvents, acid and base upon the absorption spectra of resultant dyes has been investigated. Key words: Resorcinarene, Azo Dyes, Absorption Spectra, Solvent Effect, Acid-Base Effect Rezorsinaren Bazlı Azo Boyarmaddelerin Sentezi ve Absorpsiyon Özelliklerinin İncelenmesi Özet: Bu çalışmada, çeşitli amin türevleri diazolanmış ve 3-aminokrotonitril ile kenetlenerek 2-arilhidrazon-3-ketiminokrotononitril bileşikleri elde edilmiştir. Elde edilen bileşikler, hidrazinhidrat ile etanol içerisinde reflaks edilerek bir seri 5-amino-4-arilazo-3-metil-1'H-pirazol boyaları elde edilmiştir. Elde edilen boyalar diazonlarak rezorsinol ve asetaldehit arasındaki kondenzasyondan elde edilen rezorsinaren bileşiği ile kenetlenmiş ve rezorsinaren bazlı azo boyarmaddeler sentezlenmiştir. Sentezlenen rezorsinaren bazlı azoboyarmaddelerin yapıları spektrofotometrik yöntemler kullanılarak incelendi. Sentezlenen boyarmaddelerin görünür bölge absorpsiyon spektrumları üzerine değişik çözücü, asit ve baz etkileri incelendi. Anahtar kelimeler: Rezorsiaren, Azo Boyarmadde, Absorpsiyon Spektrumu, Çözücü Etkisi, Asit-Baz Etkisi

  3. Synthesis of samarium complexes with the derivative binder of Schiff Quinolinic base. Characterization and photophysical study

    International Nuclear Information System (INIS)

    Lucas H, J.

    2016-01-01

    In this work we determined the metal: binder stoichiometry of the species formed during the UV/Vis spectrophotometric titration of the derivative binder of Schiff quinolinic base, L1 with the samarium nitrate pentahydrate in methanol. Statistical analysis of the data allowed proposing the metal: binder stoichiometry for the synthesis of the complexes which was one mole of samarium salt by 2.5 moles of binder and thus favor the formation of complexes with 1M: 1L and 1M: 2L stoichiometries. They were synthesized in aqueous-organic medium (water-ethanol), isolated and purified two complexes with stoichiometry 1 Sm: 1 L1, complex 1 and 1 Sm: 2 L1, complex 2. The overall yield of the reaction was 76%. The characterization of the formed complexes was performed by visible ultraviolet spectrometry (UV/Vis), nuclear magnetic resonance, X-ray photoelectron spectroscopy (XP S), thermal gravimetric analysis with differential scanning calorimetry (TGA/DSC), and radial distribution function. These complexes were studied by fluorescence and emission phosphorescence at variable temperature. Spectroscopic techniques used in both solution and solid demonstrated the formation and stability of these complexes. In addition XP S indicated that in both complexes the samarium retains its oxidation state 3+. Luminescence studies indicated that there is intra-binding charge transfer which decreases the transfer of light energy from the binder to the samarium. Based on the experimental results, L1 binder molecules and complexes 1 and 2 were modeled that demonstrated the proposed Nc for each complex, as well as allowed to visualize the structural arrangement of the molecules, complexes and binder. (Author)

  4. Synthesis, characterization and nano-structuration of poly-thiophene derivatives for organic photovoltaic solar cells

    International Nuclear Information System (INIS)

    Berson, S.

    2007-10-01

    This work is devoted to the synthesis of poly-thiophene derivatives with low bandgap and preserving high oxidation potential. Disubstituted thiophenes and 'Donor-Acceptor' bi-thiophenes were synthesized and then polymerized. The side chains of these polymers, donor or acceptor, were modified in order to tune the properties of material as well from the optical point of view as electrochemical. These polymers were also tested in blend with PCBM in bulk-heterojunction photovoltaic cells. Voc delivered by the devices showed a linear dependence according to the potential of oxidation of the polymers. Copolymers containing cyano-thiophene and alkyl- or alkoxy-thiophene showed values of 0.8 V. However, in spite of power conversion efficiency of 1 %, these performances remain lower than the one obtained with the P3HT. Optimizations in terms of morphology are certainly necessary. Indeed, the morphology of the active layer plays a key role in obtaining high power conversion efficiency. An original technique of nano-structuration of the polymer on a nano-metric scale was developed during this work, leading to the development of fibrillar P3HT. These nano-structures, presenting an important degree of order, are formed spontaneously in solution. Their rate compared to amorphous material is perfectly controllable and adjustable in solution and in solid state. Measurements of mobilities show a strong improvement of the transport of load within these fibrillar layers compared to a traditional film of P3HT obtained without annealing. Power conversion efficiencies of 3.6% on glass and 3.3 % on plastic were reached without annealing. (author)

  5. Synthesis, characterization and nano-structuration of poly-thiophene derivatives for organic photovoltaic solar cells

    International Nuclear Information System (INIS)

    Berson, S.

    2007-10-01

    This work is devoted to the synthesis of poly-thiophene derivatives with low bandgap and preserving high oxidation potential. Di-substituted thiophenes and 'Donor-Acceptor' bi-thiophenes were synthesized and then polymerized. The side chains of these polymers, donor or acceptor, were modified in order to tune the properties of material as well from the optical point of view as electrochemical. These polymers were also tested in blend with PCBM in bulk-heterojunction photovoltaic cells. Voc delivered by the devices showed a linear dependence according to the potential of oxidation of the polymers. Copolymers containing cyano-thiophene and alkyl- or alkoxy-thiophene showed values of 0.8 V. However, in spite of power conversion efficiency of 1 %, these performances remain lower than the one obtained with the P3HT. Optimizations in terms of morphology are certainly necessary. Indeed, the morphology of the active layer plays a key role in obtaining high power conversion efficiency. An original technique of nano-structuration of the polymer on a nano-metric scale was developed during this work, leading to the development of fibrillary P3HT. These nano-structures, presenting an important degree of order, are formed spontaneously in solution. Their rate compared to amorphous material is perfectly controllable and adjustable in solution and in solid state. Measurements of mobilities show a strong improvement of the transport of load within these fibrillary layers compared to a traditional film of P3HT obtained without annealing. Power conversion efficiencies of 3.6 % on glass and 3.3 % on plastic were reached without annealing. (author)

  6. New aminoporphyrins bearing urea derivative substituents: synthesis, characterization, antibacterial and antifungal activity

    Directory of Open Access Journals (Sweden)

    Gholamreza Karimipour

    2015-06-01

    Full Text Available This work studied the synthesis of 5,10,15-tris(4-aminophenyl-20-(N,N-dialkyl/diaryl-N-phenylurea porphyrins (P1-P4 with alkyl or aryl groups of Ph, iPr, Et and Me, respectively and also the preparation of their manganese (III and cobalt (II complexes (MnP and CoP. The P1-P4 ligands were characterized by different spectroscopic techniques (1H NMR, FTIR, UV-Vis and elemental analysis, and metalated with Mn and Co acetate salts. The antibacterial and antifungal activities of these compounds in vitro were investigated by agar-disc diffusion method against Escherichia coli (-, Pseudomonas aeruginosa (-, Staphylococcus aureus(+, Bacillus subtilis (+ and Aspergillus oryzae and Candida albicans. Results showed that antibacterial and antifungal activity of the test samples increased with increase of their concentrations and the highest activity was obtained when the concentration of porphyrin compounds was 100 µg/mL. The activity for the porphyrin ligands depended on the nature of the urea derivative substituents and increased in the order P1 > P2 > P3 >P4, which was consistent with the order of their liposolubility. MnP and CoP complexes exhibited much higher antibacterial and antifungal activity than P1-P4ligands. Further, the growth inhibitory effects of these compounds was generally in the order CoP complexes > MnP complexes > P1-P4 ligands. Among these porphyrin compounds, CoP1displayed the highest antibacterial and antifungal activity, especially with a concentration of 100 µg/mL, against all the four tested bacteria and two fungi, and therefore it could be potential to be used as drug.

  7. Synthesis, structure combined with conformational analysis, biological activities and docking studies of bis benzylidene cyclohexanone derivatives

    Directory of Open Access Journals (Sweden)

    Gehad Lotfy

    2017-07-01

    Full Text Available We report the synthesis and biological evaluation of bis benzylidne cyclohexanone derivatives 2,6-di(4-fluorobenzylidenecyclohexanone 3a and (2E,6E‐2,6‐bis({[4‐(trifluoromethylphenyl]methylidene}cyclohexanone 3b. Compound 3b crystallized in the monoclinic space group P21/n with unit cell parameters a = 29.3527(12 Å, b = 8.3147(3 Å, c = 32.7452(14 Å, β = 112.437(2°, and V = 7386.8(5 Å3, Z = 16, and Rint = 0.072 at T = 100 K. The asymmetric unit contains four independent molecules, each of which has slight differences in the bond lengths and angles. One non-classical C11D–H11F⋯F3A hydrogen bond connects the molecules. Density functional theory was used to optimize the structures and calculate the natural charges, dipole moments, frontier molecular orbitals, and NMR and UV–Vis spectroscopic properties, which are discussed and compared with the experimental data. The synthetic derivatives were evaluated for α-glucosidase inhibitory activity, and we found that compound 3a (IC50 = 96.3 ± 0.51 μM is a potent α-glucosidase inhibitor, showing superior activity to the standard drug acarbose (IC50 = 841 ± 1.73 μM. Compound 3b (IC50 = 7.92 ± 1.3 μg/mL was found to be a potent antileishmanial compound, especially compared to the antileishmanial drugs pentamidine (IC50 = 5.09 ± 0.04 μM and amphotericine B (IC50 = 0.29 ± 0.05 μg/mL. In addition, 3a and 3b have cytotoxic effects against PC3 (prostate cancer, HeLa (cervical cancer, and MCF-3 (breast cancer cell lines. Docking study for compounds activity was performed with Openeye software in order to understanding their pose of interaction in the target receptors.

  8. Practical experiences with the synthesis of [11C]CH3I through gas phase iodination reaction using a TRACERlabFXC synthesis module

    International Nuclear Information System (INIS)

    Kniess, Torsten; Rode, Katrin; Wuest, Frank

    2008-01-01

    The results of [ 11 C]CH 3 I synthesis through hydrogen gas reduction of [ 11 C]CO 2 on different nickel catalysts (HARSHAW-nickel, SHIMALITE-nickel, nickel on silica/alumina, nickel nanosize 99.99%) followed by gas phase iodination using a TRACERlab FX C synthesis unit are reported. Further reaction parameters such as furnace temperatures, flow rate of hydrogen gas and reduction time were optimized. It was found that reduction of [ 11 C]CO 2 proceeded in 28-83% yield depending on the nickel catalyst and temperature. The gas phase iodination (methane conversion) gave 31-62% of [ 11 C]CH 3 I depending on temperature and amount of iodine in the iodine furnace. [ 11 C]CH 3 I was used for heteroatom methylation reactions exemplified by a piperazine and a phenol (1 and 3). The specific activity of the 11 C-labelled products 2 and 4 was determined after HPLC purification and solid-phase extraction. Compounds 2 and 4 were obtained in 8-14% radiochemical yield (decay-corrected, based upon trapped [ 11 C]CH 4 ) within 30 min. The specific activity was determined to be in the range of 20-30 GBq/μmol at the end-of-synthesis. Nickel catalyst nanosize was found to be superior compared with other Ni catalysts tested. The relatively low specific activity may be mainly due to carbon contaminations originating from the long copper tubing (500 m) between the cyclotron and the radiochemistry facility

  9. One-step synthesis of dimethyl ether from the gas mixture containing CO2 with high space velocity

    International Nuclear Information System (INIS)

    Chen, Wei-Hsin; Lin, Bo-Jhih; Lee, How-Ming; Huang, Men-Han

    2012-01-01

    Highlights: ► A bifunctional catalyst for DME synthesis is prepared using a coprecipitation method. ► The DME synthesis from syngas at a high space velocity of is investigated. ► The reaction is dominated by chemical kinetics at lower reaction temperatures. ► Thermodynamic equilibrium governs the reaction at higher temperatures. ► 0.2 g of ZSM5 is sufficient to be blended with 1 g of the catalyst for DME synthesis. -- Abstract: Dimethyl ether (DME) has been considered as a potential hydrogen carrier used in fuel cells; it can also be consumed as a diesel substitute or chemicals. To develop the technique of DME synthesis, a bifunctional Cu–ZnO–Al 2 O 3 /ZSM5 catalyst is prepared using a coprecipitation method. The reaction characteristics of DME synthesis from syngas at a high space velocity of 15,000 mL (g cat h) −1 are investigated and the effects of reaction temperature, pressure, CO 2 concentration and ZSM5 amount on the synthesis are taken into account. The results suggest that an increase in CO 2 concentration in the feed gas substantially decreases the DME formation. The optimum reaction temperature always occurs at 225 °C, regardless of what the pressure is. It is thus recognized that the DME synthesis is governed by two different mechanisms when the reaction temperature varies. At lower reaction temperatures ( 225 °C). For the CO 2 content of 5 vol.% and the pressure of 40 atm, the maximum DME yield is 1.89 g (g cat h) −1 . It is also found that 0.2 g of ZSM5 is sufficient to be blended with 1 g of the catalyst for DME synthesis.

  10. Transformation of heavy gas oils derived from oil sands to petrochemical feedstock

    Energy Technology Data Exchange (ETDEWEB)

    Du Plessis, D.; Laureshen, C. [Alberta Energy Research Inst., Edmonton, AB (Canada)

    2006-07-01

    Alberta's petrochemical industry is primarily based on ethane. However, ethane could potentially impede future growth of Alberta's petrochemical industry because of increasing cost and diminishing supplies. Alternately, the rapidly growing oil sands production could provide abundant new feedstocks. Different integration schemes and technologies were evaluated in this study. Research on converting bitumen-derived heavy gas oil into petrochemical feedstock has resulted in the development of two novel technologies and process integration schemes, notably the NOVA heavy oil laboratory catalyst (NHC) process and the aromatic ring cleavage (ARORINCLE) process. This paper described progress to date on these two projects. The paper presented the experimental results for each scheme. For the ARORINCLE process, results were discussed in terms of the effect of process parameters on the hydrogenation step; effect of process parameters on the ring cleavage step; and integrating the upgrading and petrochemical complex. Early laboratory stage results of these two technologies were found to be encouraging. The authors recommended that work should progress to larger scale demonstration of the NHC and ARORINCLE technologies., 13 refs., 2 tabs., 5 figs.

  11. Organic titanates: a model for activating rapid room-temperature synthesis of shape-controlled CsPbBr3 nanocrystals and their derivatives.

    Science.gov (United States)

    Fang, Shaofan; Li, Guangshe; Li, Huixia; Lu, Yantong; Li, Liping

    2018-04-12

    The application of lead halide perovskite nanocrystals is challenged by the lack of strategies in rapid room-temperature synthesis with controlled morphologies. Here, we report on an initial study of adopting organic titanates as a model activator that promotes rapid room-temperature synthesis of shape-controlled, highly luminescent CsPbBr3 nanocrystals and their derivatives.

  12. Thermodynamic-Controlled Gas Phase Process for the Synthesis of Nickel Nanoparticles of Adjustable Size and Morphology

    International Nuclear Information System (INIS)

    Kauffeldt, Elena; Kauffeldt, Thomas

    2006-01-01

    Gas phase processes are a successful route for the synthesis of nano materials. Nickel particles are used in applications ranging from catalysis to nano electronics and energy storage. The application field defines the required particle size, morphology, crystallinity and purity. Nickel tetracarbonyl is the most promising precursor for the synthesis of high purity nickel particles. Due to the toxicity of this precursor and to obtain an optimal process control we developed a two-step flow type process. Nickel carbonyl and nickel particles are synthesized in a sequence of reactions. The particles are formed in a hot wall reactor at temperatures below 400 deg. C in different gas compositions. Varying the process conditions enables the adjustment of the particle size in a range from 3 to 140 nm. The controllable crystalline habits are polycrystalline, single crystals or multiple twinned particles (MTP). Spectroscopic investigations show an excellent purity. We report about the process and first investigations of the properties of the synthesized nickel nanomaterial

  13. Catalysis for Mixed Alcohol Synthesis from Biomass Derived Syngas: Cooperative Research and Development Final Report, CRADA Number CRD-08-292

    Energy Technology Data Exchange (ETDEWEB)

    Hensley, J.

    2013-04-01

    The Dow Chemical Company (Dow) developed and tested catalysts for production of mixed alcohols from synthesis gas (syngas), under research and development (R&D) projects that were discontinued a number of years ago. Dow possesses detailed laboratory notebooks, catalyst samples, and technical expertise related to this past work. The National Renewable Energy Laboratory (NREL) is conducting R&D in support of the United States Department of Energy (DOE) to develop methods for economically producing ethanol from gasified biomass. NREL is currently conducting biomass gasification research at an existing 1/2 ton/day thermochemical test platform. Both Dow and NREL believe that the ability to economically produce ethanol from biomass-derived syngas can be enhanced through collaborative testing, refinement, and development of Dow's mixed-alcohol catalysts at NREL's and/or Dow's bench- and pilot-scale facilities. Dow and NREL further agree that collaboration on improvements in catalysts as well as gasifier operating conditions (e.g., time, temperature, upstream gas treatment) will be necessary to achieve technical and economic goals for production of ethanol and other alcohols.

  14. Activity and selectivity regulation of synthesis gas reaction over supported ruthenium catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Fujimoto, K; Nobusawa, T; Fukushima, T; Tominaga, H

    1985-01-01

    The catalytic activities of supported ruthenium for synthesis-gas conversion to hydrocarbons was found to be in the following order: TiOS > Nb2O3 > ZrO2 > SiO2 > Ta2O5 > Al2O3 > V2O5 > MoO3 > WO3 > MnO2 > ZnO. Turnover frequencies of the supported ruthenium increased with decrease in dispersion of the metal particles for every carrier material. Even the activities per unit weight of metals were higher for low-dispersion ruthenium of Al2O3, TiO2, and ZrO2. The chain-growth probability of a hydrocarbon product, which is characterized by the Schulz-Flory distribution, increased markedly with decrease in the metal dispersion irrespective of the carrier material. The catalytic activity of ruthenium particles with a dispersed ruthenium increased almost linearly with an increase in reaction pressure (up to at least 2.0 MPa). 23 references, 10 figures, 3 tables.

  15. Selective conversion of synthesis gas into C2-oxygenated products using mixed-metal homogeneous catalysts

    International Nuclear Information System (INIS)

    Whyman, R.

    1986-01-01

    A feature which is a key to any wider utilization of chemistry based on synthesis gas is an understanding of, and more particularly, an ability to control, those factors which determine the selectivity of the C 1 to C 2 transformation during the hydrogenation of carbon monoxide. With the exception of the rhodium-catalyzed conversion of carbon monoxide and hydrogen into ethylene glycol and methanol, in which molar ethylene glycol/methanol selectivities of ca 2/1 may be achieved, other catalyst systems containing metals such as cobalt or ruthenium exhibit only poor selectivities to ethylene glycol. The initial studies in this area were based on the reasoning that, since the reduction of carbon monoxide to C 2 products is a complex, multi-step process, the use of appropriate combinations of metals could generate synergistic effects which might prove more effective (in terms of both catalytic activity and selectivity) than simply the sum of the individual metal components. In particular, the concept of the combination of a good hydrogenation catalyst with a good carbonylation, or ''CO insertion'', catalyst seemed particularly germane. As a result of this approach the authors discovered an unprecedented example of the effect of catalyst promoters, particularly in the enhancement of C 2 /C 1 selectivity, and one which has led to the development of composite mixed-metal homogeneous catalyst systems for the conversion of CO/H 2 into C 2 -oxygenate esters

  16. Hydrothermal synthesis of highly nitrogen-doped few-layer graphene via solid–gas reaction

    International Nuclear Information System (INIS)

    Liang, Xianqing; Zhong, Jun; Shi, Yalin; Guo, Jin; Huang, Guolong; Hong, Caihao; Zhao, Yidong

    2015-01-01

    Highlights: • A novel approach to synthesis of N-doped few-layer graphene has been developed. • The high doping levels of N in products are achieved. • XPS and XANES results reveal a thermal transformation of N bonding configurations. • The developed method is cost-effective and eco-friendly. - Abstract: Nitrogen-doped (N-doped) graphene sheets with high doping concentration were facilely synthesized through solid–gas reaction of graphene oxide (GO) with ammonia vapor in a self-designed hydrothermal system. The morphology, surface chemistry and electronic structure of N-doped graphene sheets were investigated by TEM, AFM, XRD, XPS, XANES and Raman characterizations. Upon hydrothermal treatment, up to 13.22 at% of nitrogen could be introduced into the crumpled few-layer graphene sheets. Both XPS and XANES analysis reveal that the reaction between oxygen functional groups in GO and ammonia vapor produces amide and amine species in hydrothermally treated GO (HTGO). Subsequent thermal annealing of the resultant HTGO introduces a gradual transformation of nitrogen bonding configurations in graphene sheets from amine N to pyridinic and graphitic N with the increase of annealing temperature. This study provides a simple but cost-effective and eco-friendly method to prepare N-doped graphene materials in large-scale for potential applications

  17. Combined synthesis and in situ coating of nanoparticles in the gas phase

    International Nuclear Information System (INIS)

    Laehde, Anna; Raula, Janne; Kauppinen, Esko I.

    2008-01-01

    Combined gas phase synthesis and coating of sodium chloride (NaCl) and lactose nanoparticles has been developed using an aerosol flow reactor. Nano-sized core particles were produced by the droplet-to-particle method and coated in situ by the physical vapour deposition of L-leucine vapour. The saturation of L-leucine in the reactor determined the resulting particle size and size distribution. In general, particle size increased with the addition of L-leucine and notable narrowing of the core particle size distribution was observed. In addition, homogeneous nucleation of the vapour, i.e. formation of pure L-leucine particles, was observed depending on the saturation conditions of L-leucine as well as the core particle characteristics. The effects of core particle properties, i.e. size and solid-state characteristics, on the coating process were studied by comparing the results for coated NaCl and lactose particles. During deposition, L-leucine formed a uniform coating on the surface of the core particles. The coating stabilised the nanoparticles and prevented the sintering of particles during storage.

  18. A Fifteen Year Record of Global Natural Gas Flaring Derived from Satellite Data

    International Nuclear Information System (INIS)

    Elvidge, Ch. D.; Erwin, E. H.; Ziskin, D.; Baugh, K. E.; Tuttle, B. T.; Ghosh, T.; Tuttle, B. T.; Ghosh, T.; Pack, D. W.; Zhizhin, M.

    2009-01-01

    We have produced annual estimates of national and global gas flaring and gas flaring efficiency from 1994 through 2008 using low light imaging data acquired by the Defense Meteorological Satellite Program (DMSP). Gas flaring is a widely used practice for the disposal of associated gas in oil production and processing facilities where there is insufficient infrastructure for utilization of the gas (primarily methane). Improved utilization of the gas is key to reducing global carbon emissions to the atmosphere. The DMSP estimates of flared gas volume are based on a calibration developed with a pooled set of reported national gas flaring volumes and data from individual flares. Flaring efficiency was calculated as the volume of flared gas per barrel of crude oil produced. Global gas flaring has remained largely stable over the past fifteen years, in the range of 140 to 170 billion cubic meters (BCM). Global flaring efficiency was in the seven to eight cubic meters per barrel from 1994 to 2005 and declined to 5.6 m 3 per barrel by 2008. The 2008 gas flaring estimate of 139 BCM represents 21% of the natural gas consumption of the USA with a potential retail market value of 68 billions USD. The 2008 flaring added more than 278 million metric tons of carbon dioxide equivalent (CO 2e ) into the atmosphere. The DMSP estimated gas flaring volumes indicate that global gas flaring has declined by 19% since 2005, led by gas flaring reductions in Russia and Nigeria, the two countries with the highest gas flaring levels. The flaring efficiency of both Russia and Nigeria improved from 2005 to 2008, suggesting that the reductions in gas flaring are likely the result of either improved utilization of the gas, reinjection, or direct venting of gas into the atmosphere, although the effect of uncertainties in the satellite data cannot be ruled out. It is anticipated that the capability to estimate gas flaring volumes based on satellite data will spur improved utilization of gas that

  19. Minimal variance hedging of natural gas derivatives in exponential Lévy models: Theory and empirical performance

    International Nuclear Information System (INIS)

    Ewald, Christian-Oliver; Nawar, Roy; Siu, Tak Kuen

    2013-01-01

    We consider the problem of hedging European options written on natural gas futures, in a market where prices of traded assets exhibit jumps, by trading in the underlying asset. We provide a general expression for the hedging strategy which minimizes the variance of the terminal hedging error, in terms of stochastic integral representations of the payoffs of the options involved. This formula is then applied to compute hedge ratios for common options in various models with jumps, leading to easily computable expressions. As a benchmark we take the standard Black–Scholes and Merton delta hedges. We show that in natural gas option markets minimal variance hedging with underlying consistently outperform the benchmarks by quite a margin. - Highlights: ► We derive hedging strategies for European type options written on natural gas futures. ► These are tested empirically using Henry Hub natural gas futures and options data. ► We find that our hedges systematically outperform classical benchmarks

  20. Deuterium concentration deterioration in feed synthesis gas from ammonia plant to heavy water plant (Preprint No. ED-5)

    International Nuclear Information System (INIS)

    Sah, A.K.

    1989-04-01

    Heavy Water Plant (Thal) is designed for 110 T/ Year capacity (55 T/Year each stream), with inlet deuterium concentration of feed synthesis gas at 115 ppm and depleted to 15 ppm. During first start up of plant the inlet concentration to feed synthesis gas was about 97 ppm. At that time the rich condensate recirculation was not there. To make the effective recirculation of deuterium rich condensate and minimum posssible losses some modifications were carried out in ammonia plant. Major ones are: (i)Demineralised (DM) water export for heavy water plant and urea plant which was having deuterium rich DM water connection was connected with DM water of urea plant which is not rich in deuterium, (ii)Sample cooler pump suction was connected with raw water, (iii)Ammonia plant line No.II condensate stripper was rectified during annual shut down to avoid excessive steam venting from its top and other draining, and (iv)Stripper condensate directly connected to make up water bypassing open settler to avoid evaporation and diffusion losses. With these modifications the deuterium concentration in feed synthesis gas improved to about 105 ppm. To improve it to 115 ppm, further modifications are suggested. (author). 5 figs