Sample records for polymeric coal structures

  1. Through the looking glass: Unraveling the network structure of coal

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gregory, D. M.; Stec, D. F.; Botto, R. E.

    1999-12-23

    Since the original idea by Sanada and Honda of treating coal as a three-dimensional cross-linked network, coal structure has been probed by monitoring ingress of solvents using traditional volumetric or gravimetric methods. However, using these techniques has allowed only an indirect observation of the swelling process. More recently, the authors have developed magnetic resonance microscopy (MRM) approaches for studying solvent ingress in polymeric systems, about which fundamental aspects of the swelling process can be deduced directly and quantitatively. The aim of their work is to utilize solvent transport and network response parameters obtained from these methods to assess fundamental propertiesmore » of the system under investigation. Polymer and coal samples have been studied to date. Numerous swelling parameters measured by magnetic resonance microscopy are found to correlate with cross-link density of the polymer network under investigation. Use of these parameters to assess the three-dimensional network structure of coal is discussed.« less

  2. Effect of Ni-Co Ternary Molten Salt Catalysts on Coal Catalytic Pyrolysis Process

    NASA Astrophysics Data System (ADS)

    Cui, Xin; Qi, Cong; Li, Liang; Li, Yimin; Li, Song

    2017-08-01

    In order to facilitate efficient and clean utilization of coal, a series of Ni-Co ternary molten salt crystals are explored and the catalytic pyrolysis mechanism of Datong coal is investigated. The reaction mechanisms of coal are achieved by thermal gravimetric analyzer (TGA), and a reactive kinetic model is constructed. The microcosmic structure and macerals are observed by scanning electron microscope (SEM). The catalytic effects of ternary molten salt crystals at different stages of pyrolysis are analyzed. The experimental results show that Ni-Co ternary molten salt catalysts have the capability to bring down activation energy required by pyrolytic reactions at its initial phase. Also, the catalysts exert a preferable catalytic action on macromolecular structure decomposition and free radical polycondensation reactions. Furthermore, the high-temperature condensation polymerization is driven to decompose further with a faster reaction rate by the additions of Ni-Co ternary molten salt crystal catalysts. According to pyrolysis kinetic research, the addition of catalysts can effectively decrease the activation energy needed in each phase of pyrolysis reaction.

  3. Free-radical concentrations and other properties of pile-irradiated coals

    USGS Publications Warehouse

    Friedel, R.A.; Breger, I.A.

    1959-01-01

    Five coals reacted quite differently when they were exposed to pile-irradiation. Little or no change was found in free-radical content for the three coals of lowest carbon content, whereas the two coals of highest carbon content were found to have a considerable increase in free-radical content. The infrared spectra and the apparent hardness of the irradiated coals of higher carbon content indicate that polymerization occurred. Radiation of these coals in chemical reagents may promote reactivity.

  4. 49 CFR 176.903 - Stowage of cotton or vegetable fibers with coal.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 2 2013-10-01 2013-10-01 false Stowage of cotton or vegetable fibers with coal... CARRIAGE BY VESSEL Subpart O-Detailed Requirements for Cotton and Vegetable Fibers, Motor Vehicles, Polymeric Beads, and Plastic Molding Compounds § 176.903 Stowage of cotton or vegetable fibers with coal...

  5. 49 CFR 176.903 - Stowage of cotton or vegetable fibers with coal.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 2 2014-10-01 2014-10-01 false Stowage of cotton or vegetable fibers with coal... CARRIAGE BY VESSEL Subpart O-Detailed Requirements for Cotton and Vegetable Fibers, Motor Vehicles, Polymeric Beads, and Plastic Molding Compounds § 176.903 Stowage of cotton or vegetable fibers with coal...

  6. Supercritical solvent coal extraction

    NASA Technical Reports Server (NTRS)

    Compton, L. E. (Inventor)

    1984-01-01

    Yields of soluble organic extract are increased up to about 50% by the supercritical extraction of particulate coal at a temperature below the polymerization temperature for coal extract fragments (450 C.) and a pressure from 500 psig to 5,000 psig by the conjoint use of a solvent mixture containing a low volatility, high critical temperature coal dissolution catalyst such as phenanthrene and a high volatility, low critical temperature solvent such as toluene.

  7. ELECTROKINETIC DENSIFICATION OF COAL FINES IN WASTE PONDS

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    E. James Davis

    1999-12-18

    The objective of this research was to demonstrate that electrokinetics can be used to remove colloidal coal and mineral particles from coal-washing ponds and lakes without the addition of chemical additives such as salts and polymeric flocculants. The specific objectives were: Design and develop a scaleable electrophoresis apparatus to clarify suspensions of colloidal coal and clay particles; Demonstrate the separation process using polluted waste water from the coal-washing facilities at the coal-fired power plants in Centralia, WA; Develop a mathematical model of the process to predict the rate of clarification and the suspension electrical properties needed for scale up.

  8. Investigation of electrophysical properties of allotropic modifications of carbon in the range of temperatures 140-400 K

    NASA Astrophysics Data System (ADS)

    Goshev, A. A.; Eseev, M. K.; Volkov, A. S.; Lyah, N. L.

    2017-09-01

    The paper presents the results of the investigation of allotropic modifications of carbon (coal, graphite, fullerenes, CNTs. Dependences of conductivity on the field frequency in the temperature range 140-400 K are presented. The characteristic features associated with the structure and types of hybridization are revealed. Calculation of the activation energy of carriers was performed. As well article presents experimental study of electrical properties of polymeric composites, reinforced different types of allotropic modifications of carbon (CNTs, graphite, fullerenes, coal) in alternating electrical field in frequency band from 0.01 Hz to 10 MHz. The threshold of percolation of polymer composites with various types of additives and their influence for conduction properties was estimated.

  9. Chemistry Division: Annual progress report for period ending March 31, 1987

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1987-08-01

    This report is divided into the following sections: coal chemistry; aqueous chemistry at high temperatures and pressures; geochemistry of crustal processes to high temperatures and pressures; chemistry of advanced inorganic materials; structure and dynamics of advanced polymeric materials; chemistry of transuranium elements and compounds; separations chemistry; reactions and catalysis in molten salts; surface science related to heterogeneous catalysis; electron spectroscopy; chemistry related to nuclear waste disposal; computational modeling of security document printing; and special topics. (DLC)

  10. Micro-structural characterization of the hydration products of bauxite-calcination-method red mud-coal gangue based cementitious materials.

    PubMed

    Liu, Xiaoming; Zhang, Na; Yao, Yuan; Sun, Henghu; Feng, Huan

    2013-11-15

    In this research, the micro-structural characterization of the hydration products of red mud-coal gangue based cementitious materials has been investigated through SEM-EDS, (27)Al MAS NMR and (29)Si MAS NMR techniques, in which the used red mud was derived from the bauxite calcination method. The results show that the red mud-coal gangue based cementitious materials mainly form fibrous C-A-S-H gel, needle-shaped/rod-like AFt in the early hydration period. With increasing of the hydration period, densification of the pastes were promoted resulting in the development of strength. EDS analysis shows that with the Ca/Si of red mud-coal gangue based cementitious materials increases, the average Ca/Si and Ca/(Si+Al) atomic ratio of C-A-S-H gel increases, while the average Al/Si atomic ratio of C-A-S-H gel decreases. MAS NMR analysis reveals that Al in the hydration products of red mud-coal gangue based cementitious materials exists in the forms of Al(IV) and Al(VI), but mainly in the form of Al(VI). Increasing the Ca/Si ratio of raw material promotes the conversion of [AlO4] to [AlO6] and inhibits the combination between [AlO4] and [SiO4] to form C-A-S-H gel. Meanwhile, the polymerization degree of [SiO4] in the hydration products declines. Published by Elsevier B.V.

  11. Chemistry Division annual progress report for period ending April 30, 1993

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Poutsma, M.L.; Ferris, L.M.; Mesmer, R.E.

    1993-08-01

    The Chemistry Division conducts basic and applied chemical research on projects important to DOE`s missions in sciences, energy technologies, advanced materials, and waste management/environmental restoration; it also conducts complementary research for other sponsors. The research are arranged according to: coal chemistry, aqueous chemistry at high temperatures and pressures, geochemistry, chemistry of advanced inorganic materials, structure and dynamics of advanced polymeric materials, chemistry of transuranium elements and compounds, chemical and structural principles in solvent extraction, surface science related to heterogeneous catalysis, photolytic transformations of hazardous organics, DNA sequencing and mapping, and special topics.

  12. Solids precipitation and polymerization of asphaltenes in coal-derived liquids

    DOEpatents

    Kydd, Paul H.

    1984-01-01

    The precipitation and removal of particulate solids from coal-derived liquids by adding a process-derived anti-solvent liquid fraction and continuing the precipitation process at a temperature above the melting point of the mixed liquids for sufficient time to allow the asphaltenes to polymerize and solids to settle at atmospheric pressure conditions. The resulting clarified light hydrocarbon overflow liquid contains less than about 0.02 W % ash and is suitable as turbine fuel or as boiler fuel for burning without particulate emission control equipment. An underflow liquid fraction containing less than about 0.1 W % solids along with low sulfur and nitrogen concentrations is suitable as a boiler fuel with emission control equipment.

  13. Cleavage and crosslinking of polymeric coal structures during pyrolysis. Final report

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    McMillen, D.F.; Malhotra, R.

    1992-02-01

    The ultimate objective of this project was to develop a better understanding of volatiles production to help optimize the yield and character of condensable coproducts during coal pyrolysis or mild gasification. The specific objectives were to (1) Develop pyrolysis procedures that minimize secondary reactions; and (2) Develop coal pretreatments that current knowledge suggests will prorate bond scission or prevent retrograde reactions. Our approach was to study the pyrolysis of coals and tar-loaded coals by using several techniques that span a range of heating rates and pressures. Slow-heating pyrolyses were performed at low pressures in the inlet of a field ionizationmore » mass spectrometer and at atmospheric pressures in a thermogravimetric analyzer. Moderately rapid-heating pyrolyses were performed in a vacuum TGA apparatus and in sealed silica ampules heated in a molten-salt bath. The fastest heating rates were achieved with laser pyrolysis at about 30,000 X/s. The high tar yield seen in this work where the entire volume of the coal particle becomes hot and fluid at very nearly the same time, taken together with the evident non-vapor transport of the tar under these conditions, emphasizes the importance of better understanding the development of fluidity during coal heating. This specifically includes the profound effects--long-recognized but poorly understood that mild oxidation has in suppressing coal fluidity. It also includes the more recently recognized fact that heating in the presence of an inert gas produced substantially greater fluidity than does heating in the presence of combustion gases, even if the conditions are very fuel rich and all the oxygen itself has already been consumed when the coal particles are encountered.« less

  14. Cleavage and crosslinking of polymeric coal structures during pyrolysis

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    McMillen, D.F.; Malhotra, R.

    1992-02-01

    The ultimate objective of this project was to develop a better understanding of volatiles production to help optimize the yield and character of condensable coproducts during coal pyrolysis or mild gasification. The specific objectives were to (1) Develop pyrolysis procedures that minimize secondary reactions; and (2) Develop coal pretreatments that current knowledge suggests will prorate bond scission or prevent retrograde reactions. Our approach was to study the pyrolysis of coals and tar-loaded coals by using several techniques that span a range of heating rates and pressures. Slow-heating pyrolyses were performed at low pressures in the inlet of a field ionizationmore » mass spectrometer and at atmospheric pressures in a thermogravimetric analyzer. Moderately rapid-heating pyrolyses were performed in a vacuum TGA apparatus and in sealed silica ampules heated in a molten-salt bath. The fastest heating rates were achieved with laser pyrolysis at about 30,000 X/s. The high tar yield seen in this work where the entire volume of the coal particle becomes hot and fluid at very nearly the same time, taken together with the evident non-vapor transport of the tar under these conditions, emphasizes the importance of better understanding the development of fluidity during coal heating. This specifically includes the profound effects--long-recognized but poorly understood that mild oxidation has in suppressing coal fluidity. It also includes the more recently recognized fact that heating in the presence of an inert gas produced substantially greater fluidity than does heating in the presence of combustion gases, even if the conditions are very fuel rich and all the oxygen itself has already been consumed when the coal particles are encountered.« less

  15. Reverse micelle synthesis of nanoscale metal containing catalysts

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Darab, J.G.; Fulton, J.L.; Linehan, J.C.

    1993-03-01

    The need for morphological control during the synthesis of catalyst precursor powders is generally accepted to be important. In the liquefaction of coal, for example, iron-bearing catalyst precursor particles containing individual crystallites with diameters in the 1-100 nanometer range are believed to achieve good dispersion through out the coal-solvent slurry during liquefaction 2 runs and to undergo chemical transformations to catalytically active iron sulfide phases. The production of the nanoscale powders described here employs the confining spherical microdomains comprising the aqueous phase of a modified reverse micelle (MRM) microemulsion system as nanoscale reaction vessels in which polymerization, electrochemical reduction andmore » precipitation of solvated salts can occur. The goal is to take advantage of the confining nature of micelles to kinetically hinder transformation processes which readily occur in bulk aqueous solution in order to control the morphology and phase of the resulting powder. We have prepared a variety of metal, alloy, and metal- and mixed metal-oxide nanoscale powders from appropriate MRM systems. Examples of nanoscale powders produced include Co, Mo-Co, Ni{sub 3}Fe, Ni, and various oxides and oxyhydroxides of iron. Here, we discuss the preparation and characterization of nickel metal (with a nickel oxide surface layer) and iron oxyhydroxide MRM nanoscale powders. We have used extended x-ray absorption fine structure (EXAFS) spectroscopy to study the chemical polymerization process in situ, x-ray diffraction (XRD), scanning and transmission electron microcroscopies (SEM and TEM), elemental analysis and structural modelling to characterize the nanoscale powders produced. The catalytic activity of these powders is currently being studied.« less

  16. Reverse micelle synthesis of nanoscale metal containing catalysts. [Nickel metal (with a nickel oxide surface layer) and iron oxyhydroxide nanoscale powders

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Darab, J.G.; Fulton, J.L.; Linehan, J.C.

    1993-03-01

    The need for morphological control during the synthesis of catalyst precursor powders is generally accepted to be important. In the liquefaction of coal, for example, iron-bearing catalyst precursor particles containing individual crystallites with diameters in the 1-100 nanometer range are believed to achieve good dispersion through out the coal-solvent slurry during liquefaction 2 runs and to undergo chemical transformations to catalytically active iron sulfide phases. The production of the nanoscale powders described here employs the confining spherical microdomains comprising the aqueous phase of a modified reverse micelle (MRM) microemulsion system as nanoscale reaction vessels in which polymerization, electrochemical reduction andmore » precipitation of solvated salts can occur. The goal is to take advantage of the confining nature of micelles to kinetically hinder transformation processes which readily occur in bulk aqueous solution in order to control the morphology and phase of the resulting powder. We have prepared a variety of metal, alloy, and metal- and mixed metal-oxide nanoscale powders from appropriate MRM systems. Examples of nanoscale powders produced include Co, Mo-Co, Ni[sub 3]Fe, Ni, and various oxides and oxyhydroxides of iron. Here, we discuss the preparation and characterization of nickel metal (with a nickel oxide surface layer) and iron oxyhydroxide MRM nanoscale powders. We have used extended x-ray absorption fine structure (EXAFS) spectroscopy to study the chemical polymerization process in situ, x-ray diffraction (XRD), scanning and transmission electron microcroscopies (SEM and TEM), elemental analysis and structural modelling to characterize the nanoscale powders produced. The catalytic activity of these powders is currently being studied.« less

  17. Biodegradation of coal-related model compounds. [C. versicolor

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Campbell, J.A.; Stewart, D.L.; McCulloch, M.

    1988-01-01

    The details of the specific reactions of lignin biodegradation, and the biochemistry involved, have been primarily based on the use of low molecular weight compounds representing specific substructures rather than the complex, polymeric lignin material. The authors have studied the reactions of model compounds having coal-related functionalities (ester linkages, ether linkages, PAH) with the intact organisms, cell-free filtrate, and cell-free enzyme of C. versicolor to better understand the process of biosolubilization. Many of the degradation products have been identified by gas chromatography/mass spectrometry (GC/MS). Results are discussed.

  18. Experimental study on the relationship between the mineral production capability and the physiochemical properties in the coproduction of Q phase-3CaO·3Al2O3·CaSO4 cement clinker.

    PubMed

    He, Chao; Tian, Chaochao; Li, Gang; Mei, Yahe; Zhang, Quanguo; Jiao, Youzhou

    2018-01-01

    A coproduction tests of quaternary (Q) phase(6CaO·4Al2O3·MgO·SiO2) -3CaO·3Al2O3·CaSO4 cement clinker and an experimental study on the relationship between the mineral production capability and the physiochemical properties are conducted in a two-stage multiphase reaction test bed with Changguang coal. X-ray diffractometer (XRD) analyses are performed on the coproduction clinker samples. The results demonstrate that, with the reduction in particle sizes of the coal powder and the additives and expanded screening level differences between them, both the proportion of Q phase and the mass of 3CaO·3Al2O3·CaSO4 in the clinker increase accordingly. When mixed coal powder particles are prepared through reducing particle sizes and expanding screening level differences between coal powder and additives, the additives CaO and MgO are more likely to be enclosed by coal powder to form globular polymerized particles. In addition, this preparation aids in polymerization and promotes even distribution of CaO, MgO and coal minerals, thus facilitating clinker mineral formation reactions of inorganic substances in the mixed coal powder. Target minerals, such as 2CaO·SiO2 and Q phase, are found in both industrial high-calcium limestone and low-calcium limestone coproduction clinker samples. A diffraction peak of free CaO is also evident in both samples. Compared with a coproduction clinker sample of high-calcium limestone, that of low-calcium limestone exhibits higher diffraction peaks for 2CaO·SiO2 and Q phase. With the current state of the art, it is not yet the optimum choice to substitute CaCO3 for CaO in Q-phase cement clinker coproduction. Before the technology matures and gains practical application, further study on the form and the mixing process of calcium-based additives for cement clinker coproduction will be required.

  19. Experimental study on the relationship between the mineral production capability and the physiochemical properties in the coproduction of Q phase-3CaO·3Al2O3·CaSO4 cement clinker

    PubMed Central

    Tian, Chaochao; Li, Gang; Mei, Yahe; Zhang, Quanguo; Jiao, Youzhou

    2018-01-01

    A coproduction tests of quaternary (Q) phase(6CaO·4Al2O3·MgO·SiO2) -3CaO·3Al2O3·CaSO4 cement clinker and an experimental study on the relationship between the mineral production capability and the physiochemical properties are conducted in a two-stage multiphase reaction test bed with Changguang coal. X-ray diffractometer (XRD) analyses are performed on the coproduction clinker samples. The results demonstrate that, with the reduction in particle sizes of the coal powder and the additives and expanded screening level differences between them, both the proportion of Q phase and the mass of 3CaO·3Al2O3·CaSO4 in the clinker increase accordingly. When mixed coal powder particles are prepared through reducing particle sizes and expanding screening level differences between coal powder and additives, the additives CaO and MgO are more likely to be enclosed by coal powder to form globular polymerized particles. In addition, this preparation aids in polymerization and promotes even distribution of CaO, MgO and coal minerals, thus facilitating clinker mineral formation reactions of inorganic substances in the mixed coal powder. Target minerals, such as 2CaO·SiO2 and Q phase, are found in both industrial high-calcium limestone and low-calcium limestone coproduction clinker samples. A diffraction peak of free CaO is also evident in both samples. Compared with a coproduction clinker sample of high-calcium limestone, that of low-calcium limestone exhibits higher diffraction peaks for 2CaO·SiO2 and Q phase. With the current state of the art, it is not yet the optimum choice to substitute CaCO3 for CaO in Q-phase cement clinker coproduction. Before the technology matures and gains practical application, further study on the form and the mixing process of calcium-based additives for cement clinker coproduction will be required. PMID:29634732

  20. Polymeric, Metallic, and Other Glasses in Introductory Chemistry

    ERIC Educational Resources Information Center

    Hawkes, Stephen J.

    2008-01-01

    Non-ceramic glasses are not adequately discussed in introductory chemistry. Such glasses include polycarbonate, which many corrective lenses are made of, amber, enamel, gelatin, hard candy, coal, refrigerated glycerol, and metallic glasses that have been marketed in recent decades. What is usually discussed in elementary texts is siliceous glass,…

  1. Classification of Structural Coal-Controlling Styles and Analysis on Structural Coal-Controlling Actions

    NASA Astrophysics Data System (ADS)

    Zhan, Wen-feng

    2017-11-01

    Tectonism was the primary geologic factors for controlling the formation, deformation, and occurrence of coal measures. As the core of a new round of prediction and evaluation on the coalfield resource potential, the effect of coal-controlling structure was further strengthened and deepened in related researches. By systematically combing the tectonic coal-controlling effect and structure, this study determined the geodynamical classification basis for coal-controlling structures. According to the systematic analysis and summary on the related research results, the coal-controlling structure was categorized into extensional structure, compressive structure, shearing and rotational structure, inverted structure, as well as the sliding structure, syndepositional structure with coalfield structure characteristics. In accordance with the structure combination and distribution characteristics, the six major classes were further classified into 32 subclasses. Moreover, corresponding mode maps were drawn to discuss the basic characteristics and effect of the coal-controlling structures.

  2. Low temperature pyrolysis of coal or oil shale in the presence of calcium compounds

    DOEpatents

    Khan, M. Rashid

    1988-01-01

    A coal pyrolysis technique or process is described in which particulate coal is pyrolyzed in the presence of about 5 to 21 wt. % of a calcium compound selected from calcium oxide, calcined (hydrate) dolomite, or calcined calcium hydrate to produce a high quality hydrocarbon liquid and a combustible product gas which are characterized by low sulfur content. The pyrolysis is achieved by heating the coal-calcium compound mixture at a relatively slow rate at a temperature of about 450.degree. to 700.degree. C. over a duration of about 10 to 60 minutes in a fixed or moving bed reactor. The gas exhibits an increased yield in hydrogen and C.sub.1 -C.sub.8 hydrocarbons and a reduction in H.sub.2 S over gas obtainable by pyrolyzing cola without the calcium compound. The liquid product obtained is of a sufficient quality to permit its use directly as a fuel and has a reduced sulfur and oxygen content which inhibits polymerization during storage.

  3. 30 CFR 817.84 - Coal mine waste: Impounding structures.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 3 2014-07-01 2014-07-01 false Coal mine waste: Impounding structures. 817.84... ACTIVITIES § 817.84 Coal mine waste: Impounding structures. New and existing impounding structures constructed of coal mine waste or intended to impound coal mine waste shall meet the requirements of § 817.81...

  4. 30 CFR 816.84 - Coal mine waste: Impounding structures.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Coal mine waste: Impounding structures. 816.84... ACTIVITIES § 816.84 Coal mine waste: Impounding structures. New and existing impounding structures constructed of coal mine waste or intended to impound coal mine waste shall meet the requirements of § 816.81...

  5. 30 CFR 816.84 - Coal mine waste: Impounding structures.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 3 2011-07-01 2011-07-01 false Coal mine waste: Impounding structures. 816.84... ACTIVITIES § 816.84 Coal mine waste: Impounding structures. New and existing impounding structures constructed of coal mine waste or intended to impound coal mine waste shall meet the requirements of § 816.81...

  6. 30 CFR 817.84 - Coal mine waste: Impounding structures.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Coal mine waste: Impounding structures. 817.84... ACTIVITIES § 817.84 Coal mine waste: Impounding structures. New and existing impounding structures constructed of coal mine waste or intended to impound coal mine waste shall meet the requirements of § 817.81...

  7. 30 CFR 816.84 - Coal mine waste: Impounding structures.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 3 2012-07-01 2012-07-01 false Coal mine waste: Impounding structures. 816.84... ACTIVITIES § 816.84 Coal mine waste: Impounding structures. New and existing impounding structures constructed of coal mine waste or intended to impound coal mine waste shall meet the requirements of § 816.81...

  8. 30 CFR 817.84 - Coal mine waste: Impounding structures.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 3 2011-07-01 2011-07-01 false Coal mine waste: Impounding structures. 817.84... ACTIVITIES § 817.84 Coal mine waste: Impounding structures. New and existing impounding structures constructed of coal mine waste or intended to impound coal mine waste shall meet the requirements of § 817.81...

  9. 30 CFR 817.84 - Coal mine waste: Impounding structures.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 3 2013-07-01 2013-07-01 false Coal mine waste: Impounding structures. 817.84... ACTIVITIES § 817.84 Coal mine waste: Impounding structures. New and existing impounding structures constructed of coal mine waste or intended to impound coal mine waste shall meet the requirements of § 817.81...

  10. 30 CFR 816.84 - Coal mine waste: Impounding structures.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 3 2014-07-01 2014-07-01 false Coal mine waste: Impounding structures. 816.84... ACTIVITIES § 816.84 Coal mine waste: Impounding structures. New and existing impounding structures constructed of coal mine waste or intended to impound coal mine waste shall meet the requirements of § 816.81...

  11. 30 CFR 817.84 - Coal mine waste: Impounding structures.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 3 2012-07-01 2012-07-01 false Coal mine waste: Impounding structures. 817.84... ACTIVITIES § 817.84 Coal mine waste: Impounding structures. New and existing impounding structures constructed of coal mine waste or intended to impound coal mine waste shall meet the requirements of § 817.81...

  12. 30 CFR 816.84 - Coal mine waste: Impounding structures.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 3 2013-07-01 2013-07-01 false Coal mine waste: Impounding structures. 816.84... ACTIVITIES § 816.84 Coal mine waste: Impounding structures. New and existing impounding structures constructed of coal mine waste or intended to impound coal mine waste shall meet the requirements of § 816.81...

  13. Fast and Selective Preconcentration of Europium from Wastewater and Coal Soil by Graphene Oxide/Silane@Fe3O4 Dendritic Nanostructure.

    PubMed

    Patra, Santanu; Roy, Ekta; Madhuri, Rashmi; Sharma, Prashant K

    2015-05-19

    In this study, nanocomposite of graphene oxide and silane modified magnetic nanoparticles (silane@Fe3O4) were synthesized in a form of dendritic structure. For this, silane@Fe3O4 nanoparticle gets sandwiched between two layers of graphene oxide by chemical synthesis route. The synthesized dendritic structure was used as a monomer for synthesis of europium ion imprinted polymer. The synthesis of imprinted polymer was contemplated onto the surface of the vinyl group modified silica fiber by activated generated free radical atom-transfer radical polymerization, that is, AGET-ATRP technique. The synthesized dendritic monomer was characterized by XRD, FT-IR, VSM, FE-SEM, and TEM analyses. The imprinted polymer modified silica fiber was first validated in the aqueous and blood samples for successful extraction and detection of europium ion with limit of detection = 0.050 pg mL(-1) (signal/noise = 3). The imprinted polymer modified silica fiber was also used for preconcentration and separation of europium metal ion from various soil samples of coal mine areas. However, the same silica fiber was also used for wastewater treatment and shows 100% performance for europium removal. The findings herein suggested that dendritic nanocomposite could be potentially used as a highly effective material for the enrichment and preconcentration of europium or other trivalent lanthanides/actinides in nuclear waste management.

  14. Structurally Altered Hard Coal in the Areas of Tectonic Disturbances - An Initial Attempt at Classification

    NASA Astrophysics Data System (ADS)

    Godyń, Katarzyna

    2016-09-01

    As regards the exploitation of hard coal seams, the near-fault zones and faults themselves are considered to be particularly dangerous areas, which is due to a high probability of the occurrence of gasogeodynamic phenomena. Tectonic dislocations running across a seam have a destructive impact on coal. Degradation of the coal structure, particularly visible in the microscale, is reflected in the coal's strength or gas properties. Such "structurally altered" coal is characterized by the presence of numerous fracturings, crushed areas, or dislocations of some of its fragments, and sometimes even the total destruction of the original structure. The present paper provides a detailed analysis and description of near-fault coal obtained from selected seams of the Upper Silesian Coal Basin, completed due to the application of optical methods. Both the type and the degree of changes in the structure of such coal were identified. On this basis, the author attempted to systematize the nomenclature used in relation to selected Upper Silesian hard coal seams, which, in turn, resulted in a proposed classification of the "altered structures" of the near-fault coal.

  15. Applications of molecular modeling in coal research

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Carlson, G.A.; Faulon, J.L.

    Over the past several years, molecular modeling has been applied to study various characteristics of coal molecular structures. Powerful workstations coupled with molecular force-field-based software packages have been used to study coal and coal-related molecules. Early work involved determination of the minimum-energy three-dimensional conformations of various published coal structures (Given, Wiser, Solomon and Shinn), and the dominant role of van der Waals and hydrogen bonding forces in defining the energy-minimized structures. These studies have been extended to explore various physical properties of coal structures, including density, microporosity, surface area, and fractal dimension. Other studies have related structural characteristics to cross-linkmore » density and have explored small molecule interactions with coal. Finally, recent studies using a structural elucidation (molecular builder) technique have constructed statistically diverse coal structures based on quantitative and qualitative data on coal and its decomposition products. This technique is also being applied to study coalification processes based on postulated coalification chemistry.« less

  16. Deashing of coal liquids with ceramic membrane microfiltration and diafiltration

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bishop, B.; Goldsmith, R.

    1995-12-31

    Removal of mineral matter from liquid hydrocarbons derived from the direct liquefaction of coal is required for product acceptability. Current methods include critical solvent deashing (Rose{sup {reg_sign}} process from Kerr-McGee) and filtration (U.S. Filter leaf filter as used by British Coal). These methods produce ash reject streams containing up to 15% of the liquid hydrocarbon product. Consequently, CeraMem proposed the use of low cost, ceramic crossflow membranes for the filtration of coal liquids bottoms to remove mineral matter and subsequent diafiltration (analogous to cake washing in dead-ended filtration) for the removal of coal liquid from the solids stream. The usemore » of these ceramic crossflow membranes overcomes the limitations of traditional polymeric crossflow membranes by having the ability to operate at elevated temperature and to withstand prolonged exposure to hydrocarbon and solvent media. In addition, CeraMem`s membrane filters are significantly less expensive than competitive ceramic membranes due to their unique construction. With these ceramic membrane filters, it may be possible to reduce the product losses associated with traditional deashing processes at an economically attractive cost. The performance of these ceramic membrane microfilters is discussed.« less

  17. CAMD studies of coal structure and coal liquefaction

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Faulon, J.L.; Carlson, G.A.

    The macromolecular structure of coal is essential to understand the mechanisms occurring during coal liquefaction. Many attempts to model coal structure can be found in the literature. More specifically for high volatile bituminous coal, the subject of interest the most commonly quoted models are the models of Given, Wiser, Solomon, and Shinn. In past work, the authors`s have used computer-aided molecular design (CAMD) to develop three-dimensional representations for the above coal models. The three-dimensional structures were energy minimized using molecular mechanics and molecular dynamics. True density and micopore volume were evaluated for each model. With the exception of Given`s model,more » the computed density values were found to be in agreement with the corresponding experimental results. The above coal models were constructed by a trial and error technique consisting of a manual fitting of the-analytical data. It is obvious that for each model the amount of data is small compared to the actual complexity of coal, and for all of the models more than one structure can be built. Hence, the process by which one structure is chosen instead of another is not clear. In fact, all the authors agree that the structure they derived was only intended to represent an {open_quotes}average{close_quotes} coal model rather than a unique correct structure. The purpose of this program is further develop CAMD techniques to increase the understanding of coal structure and its relationship to coal liquefaction.« less

  18. Coal: Its Structure and Some of Its Uses.

    ERIC Educational Resources Information Center

    Phillips, P. S.

    1981-01-01

    Describes the formation, chemical structure, and several uses of coal. The history of coal usage, production processes, coal tar products, and production of petroleum and other hydrocarbons from coal are also described. (DS)

  19. Breaking the limits of structural and mechanical imaging of the heterogeneous structure of coal macerals

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Collins, L.; Tselev, A.; Jesse, S.

    The correlation between local mechanical (elasto-plastic) and structural (composition) properties of coal presents significant fundamental and practical interest for coal processing and the development of rheological models of coal to coke transformations and for advancing novel approaches. Here, we explore the relationship between the local structural, chemical composition and mechanical properties of coal using a combination of confocal micro-Raman imaging and band excitation atomic force acoustic microscopy (BE-AFAM) for a bituminous coal. This allows high resolution imaging (10s of nm) of mechanical properties of the heterogeneous (banded) architecture of coal and correlating them to the optical gap, average crystallite size,more » the bond-bending disorder of sp2 aromatic double bonds and the defect density. This methodology hence allows the structural and mechanical properties of coal components (lithotypes, microlithotypes, and macerals) to be understood, and related to local chemical structure, potentially allowing for knowledge-based modelling and optimization of coal utilization processes.« less

  20. [Macromolecular aromatic network characteristics of Chinese power coal analyzed by synchronous fluorescence and X-ray diffraction].

    PubMed

    Ye, Cui-Ping; Feng, Jie; Li, Wen-Ying

    2012-07-01

    Coal structure, especially the macromolecular aromatic skeleton structure, has a strong influence on coke reactivity and coal gasification, so it is the key to grasp the macromolecular aromatic skeleton coal structure for getting the reasonable high efficiency utilization of coal. However, it is difficult to acquire their information due to the complex compositions and structure of coal. It has been found that the macromolecular aromatic network coal structure would be most isolated if small molecular of coal was first extracted. Then the macromolecular aromatic skeleton coal structure would be clearly analyzed by instruments, such as X-ray diffraction (XRD), fluorescence spectroscopy with synchronous mode (Syn-F), Gel permeation chromatography (GPC) etc. Based on the previous results, according to the stepwise fractional liquid extraction, two Chinese typical power coals, PS and HDG, were extracted by silica gel as stationary phase and acetonitrile, tetrahydrofuran (THF), pyridine and 1-methyl-2-pyrollidinone (NMP) as a solvent group for sequential elution. GPC, Syn-F and XRD were applied to investigate molecular mass distribution, condensed aromatic structure and crystal characteristics. The results showed that the size of aromatic layers (La) is small (3-3.95 nm) and the stacking heights (Lc) are 0.8-1.2 nm. The molecular mass distribution of the macromolecular aromatic network structure is between 400 and 1 130 amu, with condensed aromatic numbers of 3-7 in the structure units.

  1. Composition and structure of calcium aluminosilicate microspheres

    NASA Astrophysics Data System (ADS)

    Sharonova, O. M.; Oreshkina, N. A.; Zhizhaev, A. M.

    2017-06-01

    The composition was studied of calcium aluminosilicate microspheres of three morphological types in high-calcium fly ash from combustion of brown coal from the Kansk-Achinsk basin in slag-tap boilers at temperatures from 1400 to 1500°C and sampled in the first field of electrostatic precipitators at the Krasnoyarsk Cogeneration Power Station no. 2 (TETs-2). Gross compositions and the composition of local areas were determined using a scanning electron microscopy technique and an energy-dispersive analysis with full mapping of globules. With a high content of basic oxides O ox (68 to 79 wt %) and a low content of acid oxides K ox (21 to 31 wt %), type 1 microspheres are formed. They consist of heterogeneous areas having a porous structure and crystalline components in which the content of CaO, SiO2, or Al2O3 differs by two to three times and the content of MgO differs by seven times. With a lower content of O ox (55 to 63 wt %) and an elevated content of K ox (37 to 45 wt %), type 2 microspheres are formed. They are more homogeneous in the composition and structure and consist of similar crystalline components. Having a close content of O ox (46 to 53 wt %) and K ox (47 to 54 wt %), type 3 microspheres, which are a dense matter consisting of amorphous substance with submicron- and nanostructure of crystalline components, are formed. The basic precursor in formation of high-calcium aluminosilicate microspheres is calcium from the organomineral matter of coals with various contribution of Mg, Fe, S, or Na from the coal organic matter and Al, Fe, S, or Si in the form of single mineral inclusions in a coal particle. On the basis of the available data, the effect was analyzed of the composition of a CaO-MgO-Al2O3-SiO2-FeO system on the melting and viscous properties of the matter in microspheres and formation of globules of different morphology. The results of this analysis will help to find a correlation with properties of microspheres in their use as functional microaggregates in cement or polymeric composite materials, or in the production of ceramic membranes or zeolite sorbents.

  2. Optimizing and Characterizing Geopolymers from Ternary Blend of Philippine Coal Fly Ash, Coal Bottom Ash and Rice Hull Ash.

    PubMed

    Kalaw, Martin Ernesto; Culaba, Alvin; Hinode, Hirofumi; Kurniawan, Winarto; Gallardo, Susan; Promentilla, Michael Angelo

    2016-07-15

    Geopolymers are inorganic polymers formed from the alkaline activation of amorphous alumino-silicate materials resulting in a three-dimensional polymeric network. As a class of materials, it is seen to have the potential of replacing ordinary Portland cement (OPC), which for more than a hundred years has been the binder of choice for structural and building applications. Geopolymers have emerged as a sustainable option vis-à-vis OPC for three reasons: (1) their technical properties are comparable if not better; (2) they can be produced from industrial wastes; and (3) within reasonable constraints, their production requires less energy and emits significantly less CO₂. In the Philippines, the use of coal ash, as the alumina- and silica- rich geopolymer precursor, is being considered as one of the options for sustainable management of coal ash generation from coal-fired power plants. However, most geopolymer mixes (and the prevalent blended OPC) use only coal fly ash. The coal bottom ash, having very few applications, remains relegated to dumpsites. Rice hull ash, from biomass-fired plants, is another silica-rich geopolymer precursor material from another significantly produced waste in the country with only minimal utilization. In this study, geopolymer samples were formed from the mixture of coal ash, using both coal fly ash (CFA) and coal bottom ash (CBA), and rice hull ash (RHA). The raw materials used for the geopolymerization process were characterized using X-ray fluorescence spectroscopy (XRF) for elemental and X-ray diffraction (XRD) for mineralogical composition. The raw materials' thermal stability and loss on ignition (LOI) were determined using thermogravimetric analysis (TGA) and reactivity via dissolution tests and inductively-coupled plasma mass spectrometry (ICP) analysis. The mechanical, thermal and microstructural properties of the geopolymers formed were analyzed using compression tests, Fourier transform infra-red spectroscopy (FTIR), scanning electron microscopy (SEM) and thermogravimetric analysis (TGA). Using a Scheffé-based mixture design, targeting applications with low thermal conductivity, light weight and moderate strength and allowing for a maximum of five percent by mass of rice hull ash in consideration of the waste utilization of all three components, it has been determined that an 85-10-5 by weight ratio of CFA-CBA-RHA activated with 80-20 by mass ratio of 12 M NaOH and sodium silicate (55% H₂O, modulus = 3) produced geopolymers with a compressive strength of 18.5 MPa, a volumetric weight of 1660 kg/m³ and a thermal conductivity of 0.457 W/m-°C at 28-day curing when pre-cured at 80 °C for 24 h. For this study, the estimates of embodied energy and CO₂ were all below 1.7 MJ/kg and 0.12 kg CO₂/kg, respectively.

  3. Characterization of Coal Porosity for Naturally Tectonically Stressed Coals in Huaibei Coal Field, China

    PubMed Central

    Li, Xiaoshi; Hou, Quanlin; Li, Zhuo; Wei, Mingming

    2014-01-01

    The enrichment of coalbed methane (CBM) and the outburst of gas in a coal mine are closely related to the nanopore structure of coal. The evolutionary characteristics of 12 coal nanopore structures under different natural deformational mechanisms (brittle and ductile deformation) are studied using a scanning electron microscope (SEM) and low-temperature nitrogen adsorption. The results indicate that there are mainly submicropores (2~5 nm) and supermicropores (<2 nm) in ductile deformed coal and mesopores (10~100 nm) and micropores (5~10 nm) in brittle deformed coal. The cumulative pore volume (V) and surface area (S) in brittle deformed coal are smaller than those in ductile deformed coal which indicates more adsorption space for gas. The coal with the smaller pores exhibits a large surface area, and coal with the larger pores exhibits a large volume for a given pore volume. We also found that the relationship between S and V turns from a positive correlation to a negative correlation when S > 4 m2/g, with pore sizes <5 nm in ductile deformed coal. The nanopore structure (<100 nm) and its distribution could be affected by macromolecular structure in two ways. Interconversion will occur among the different size nanopores especially in ductile deformed coal. PMID:25126601

  4. Geotechnical approaches to coal ash content control in mining of complex structure deposits

    NASA Astrophysics Data System (ADS)

    Batugin, SA; Gavrilov, VL; Khoyutanov, EA

    2017-02-01

    Coal deposits having complex structure and nonuniform quality coal reserves require improved processes of production quality control. The paper proposes a method to present coal ash content as components of natural and technological dilution. It is chosen to carry out studies on the western site of Elginsk coal deposit, composed of four coal beds of complex structure. The reported estimates of coal ash content in the beds with respect to five components point at the need to account for such data in confirmation exploration, mine planning and actual mining. Basic means of analysis and control of overall ash content and its components are discussed.

  5. Coal as an abundant source of graphene quantum dots

    NASA Astrophysics Data System (ADS)

    Ye, Ruquan; Xiang, Changsheng; Lin, Jian; Peng, Zhiwei; Huang, Kewei; Yan, Zheng; Cook, Nathan P.; Samuel, Errol L. G.; Hwang, Chih-Chau; Ruan, Gedeng; Ceriotti, Gabriel; Raji, Abdul-Rahman O.; Martí, Angel A.; Tour, James M.

    2013-12-01

    Coal is the most abundant and readily combustible energy resource being used worldwide. However, its structural characteristic creates a perception that coal is only useful for producing energy via burning. Here we report a facile approach to synthesize tunable graphene quantum dots from various types of coal, and establish that the unique coal structure has an advantage over pure sp2-carbon allotropes for producing quantum dots. The crystalline carbon within the coal structure is easier to oxidatively displace than when pure sp2-carbon structures are used, resulting in nanometre-sized graphene quantum dots with amorphous carbon addends on the edges. The synthesized graphene quantum dots, produced in up to 20% isolated yield from coal, are soluble and fluorescent in aqueous solution, providing promise for applications in areas such as bioimaging, biomedicine, photovoltaics and optoelectronics, in addition to being inexpensive additives for structural composites.

  6. Coal as an abundant source of graphene quantum dots.

    PubMed

    Ye, Ruquan; Xiang, Changsheng; Lin, Jian; Peng, Zhiwei; Huang, Kewei; Yan, Zheng; Cook, Nathan P; Samuel, Errol L G; Hwang, Chih-Chau; Ruan, Gedeng; Ceriotti, Gabriel; Raji, Abdul-Rahman O; Martí, Angel A; Tour, James M

    2013-01-01

    Coal is the most abundant and readily combustible energy resource being used worldwide. However, its structural characteristic creates a perception that coal is only useful for producing energy via burning. Here we report a facile approach to synthesize tunable graphene quantum dots from various types of coal, and establish that the unique coal structure has an advantage over pure sp2-carbon allotropes for producing quantum dots. The crystalline carbon within the coal structure is easier to oxidatively displace than when pure sp2-carbon structures are used, resulting in nanometre-sized graphene quantum dots with amorphous carbon addends on the edges. The synthesized graphene quantum dots, produced in up to 20% isolated yield from coal, are soluble and fluorescent in aqueous solution, providing promise for applications in areas such as bioimaging, biomedicine, photovoltaics and optoelectronics, in addition to being inexpensive additives for structural composites.

  7. The adaption of coal quality to furnace structure

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zhang, Z.; Shun, X.

    1996-12-31

    This paper gives the research result of coal quality adaption to furnace structure. The designing of a furnace is based on the coal quality that the furnace would fire. If the coal fired in the furnace differs from the design coal, there would be a lot of problems such as flame stability, coal burn-out rate and slagging problem for the furnace during its operation. In order to know the adaptional range of coal quality for an existing furnace the authors had chosen three different furnaces and 18 kinds of coals in their research work. To understand the coal combustion characteristicsmore » they introduce different indexes to show different processes of coal combustion. These indexes include Fz index which demonstrates the coal combustion based on its utility analyzed result, flame stability index, combustion characteristic index and char burn-out index which are based on the analyzed result of thermogravimetric characteristic. As a furnace is built up and set into operation its flame stability, burn-out rate and ash deposition are definite. If a furnace`s fuel changes its structure characteristics and operation condition will change. A relation between coal quality to furnace structure is based on a lot of regressional analysis results of existing furnaces and their fuels. Based on this relation the adaption of coal quality for a furnace are defined and the kinds of coal furnace fired are optimized to its design fuel.« less

  8. Influence of Geological Structure on Coal and Gas Outburst Occurrences in Turkish Underground Coal Mines

    NASA Astrophysics Data System (ADS)

    Esen, Olgun; Özer, Samet Can; Fişne, Abdullah

    2015-04-01

    Coal and gas outbursts are sudden and violent releases of gas and in company with coal that result from a complex function of geology, stress regime with gas pressure and gas content of the coal seam. The phenomena is referred to as instantaneous outbursts and have occurred in virtually all the major coal producing countries and have been the cause of major disasters in the world mining industry. All structures from faults to joints and cleats may supply gas or lead to it draining away. Most geological structures influence the way in which gas can drain within coal seams. From among all the geological factors two groups can be distinguished: parameters characterising directly the occurrence and geometry of the coal seams; parameters characterising the tectonic disturbances of the coal seams and neighbouring rocks. Also dykes may act as gas barriers. When the production of the coal seam is advanced in mine working areas, these barriers are failed mostly in the weak and mylonitized zones. Geology also plays a very important role in the outburst process. Coal seams of complex geological structure including faults, folds, and fractured rocks are liable to outbursts if coal seams and neighbouring rocks have high gas content level. The purpose of the study is to enlighten the coal industry in Turkey to improving mine safety in underground coal production and decrease of coal and gas outburst events due to increasing depth of mining process. In Turkey; the years between 1969 and 2013, the number of 90 coal and gas outbursts took place in Zonguldak Hard Coal Basin in both Kozlu and Karadon Collieries. In this study the liability to coal and gas outburst of the coal seams are investigated by measuring the strength of coal and the rock pressure. The correlation between these measurements and the event locations shows that the geological structures resulted in 52 events out of 90 events; 19 events close to the fault zones, 25 events thorough the fault zones and 8 events in the zones where sudden changes of inclination and/or thickness of the coal seam.

  9. Effects of low-temperature catalytic pretreatments on coal structure and reactivity in liquefaction. Final technical report, Volume 1 - effects of solvents, catalysts and temperature conditions on conversion and structural changes of low-rank coals

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Huang, Lili; Schobert, Harold H.; Song, Chunshan

    1998-01-01

    The main objectives of this project were to study the effects of low-temperature pretreatments on coal structure and their impacts on subsequent liquefaction. The effects of pretreatment temperatures, catalyst type, coal rank, and influence of solvent were examined. Specific objectives were to identify the basic changes in coal structure induced by catalytic and thermal pretreatments, and to determine the reactivity of the catalytically and thermally treated coals for liquefaction. In the original project management plan it was indicated that six coals would be used for the study. These were to include two each of bituminous, subbituminous, and lignite rank. Formore » convenience in executing the experimental work, two parallel efforts were conducted. The first involved the two lignites and one subbituminous coal; and the second, the two bituminous coals and the remaining subbituminous coal. This Volume presents the results of the first portion of the work, studies on two lignites and one subbituminous coal. The remaining work accomplished under this project will be described and discussed in Volume 2 of this report. The objective of this portion of the project was to determine and compare the effects of solvents, catalysts and reaction conditions on coal liquefaction. Specifically, the improvements of reaction conversion, product distribution, as well as the structural changes in the coals and coal-derived products were examined. This study targeted at promoting hydrogenation of the coal-derived radicals, generated during thermal cleavage of chemical bonds, by using a good hydrogen donor-solvent and an effective catalyst. Attempts were also made in efforts to match the formation and hydrogenation of the free radicals and thus to prevent retrogressive reaction.« less

  10. Controlled short residence time coal liquefaction process

    DOEpatents

    Anderson, Raymond P.; Schmalzer, David K.; Wright, Charles H.

    1982-05-04

    Normally solid dissolved coal product and a distillate liquid product are produced by continuously passing a feed slurry comprising raw feed coal and a recycle solvent oil and/or slurry together with hydrogen to a preheating-reaction zone (26, alone, or 26 together with 42), the hydrogen pressure in the preheating-reaction zone being at least 1500 psig (105 kg/cm.sup.2), reacting the slurry in the preheating-reaction zone (26, or 26 with 42) at a temperature in the range of between about 455.degree. and about 500.degree. C. to dissolve the coal to form normally liquid coal and normally solid dissolved coal. A total slurry residence time is maintained in the reaction zone ranging from a finite value from about 0 to about 0.2 hour, and reaction effluent is continuously and directly contacted with a quenching fluid (40, 68) to substantially immediately reduce the temperature of the reaction effluent to below 425.degree. C. to substantially inhibit polymerization so that the yield of insoluble organic matter comprises less than 9 weight percent of said feed coal on a moisture-free basis. The reaction is performed under conditions of temperature, hydrogen pressure and residence time such that the quantity of distillate liquid boiling within the range C.sub.5 -455.degree. C. is an amount at least equal to that obtainable by performing the process under the same conditions except for a longer total slurry residence time, e.g., 0.3 hour. Solvent boiling range liquid is separated from the reaction effluent and recycled as process solvent.

  11. Macromolecular structure of coals. 6. Mass spectroscopic analysis of coal-derived liquids

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hooker, D.T.; Lucht, L.M.; Peppas, N.A.

    1986-02-01

    The macromolecular structure of coal networks was analyzed by depolymerizing coal samples using the Sternberg reductive alkylation and the Miyake alkylation techniques. Electron impact mass spectra showed peaks of greater abundance of 125-132, 252-260, 383-391, and 511-520 m/z ratios. Based on analysis of the patterns of the spectra, the cluster size of the cross-linked structure of bituminous coals was determined as 126-130. Various chemical species were identified.

  12. Comparison of H2S adsorption by two hydrogel composite (HBC) derived by Empty Fruit Bunch (EFB) biochar and Coal Fly Ash (CFA)

    NASA Astrophysics Data System (ADS)

    Meri, N. H.; Alias, A. B.; Talib, N.; Rashid, Z. A.; Ghani, W. A. W. A. K.

    2018-03-01

    This study are covered the adsorption performance of two adsorbent Empty Fruit Bunch Hydrogel Biochar Composite (EFB-HBC) and Coal Fly Ash Hydrogel Composite (CFA-HC) on hydrogen sulphide. The EFB biochar were produce by pyrolysed and heated from room temperature to 550˚C at 10˚C/min under the Nitrogen flow. Meanwhile, coal fly ash collected from a power plant located in Selangor, Malaysia. Both of the materials is a waste from different industries and became the precursor to our adsorbents. EFB biochar and coal fly ash has been synthesized to become hydrogel by polymerization process with acrylamide (AAm) as monomer, N,N’-methylene bisacry lamide (MBA) as cross linker and ammonium persulfate (APS) as initiator. In addition, because of the speciality of hydrogel itself, which is has high ability in storing water, the effect of H2O wetness on EFB-HBC and CFA-HC were investigate in adsorption of H2S. EFB-HBC gave a longest breakthrough time and highest adsorption capacity compared with CFA-HC in both condition (dry/wet). The result also indicated that, the increased the bed height, increased the adsorption capacity.

  13. Resource Management Technology: Los Alamos Technical Capabilities for Emergency Management,

    DTIC Science & Technology

    1983-07-18

    synthetic fuels from coal (analogous to the Fischer-Tropsch process), olefin polymerization, and flue - gas desulfurization . In order to successfully...world. It has been a major research effort here for decades. Also, in the area of desulfurization of flue gases, Los Alamos scientists have been...Tectonic and Geochemical Controls on Copper-Molybdenum Porphyry Mineralization in the Southwestern United States (M. J. Aldrich and A. W. Laughlin) 1.0.6

  14. Unlocking the Structure and Dynamics of Thin Polymeric Films

    DTIC Science & Technology

    2016-11-13

    AFRL-AFOSR-JP-TR-2016-0092 Unlocking the Structure and Dynamics of Thin Polymeric Films Andrew Whittaker THE UNIVERSITY OF QUEENSLAND Final Report 11...Final 3. DATES COVERED (From - To)  15 Jun 2015 to 16 Jun 2016 4. TITLE AND SUBTITLE Unlocking the Structure and Dynamics of Thin Polymeric Films 5a...the interfacial structure that are inherent in thin films affects how polymers behave. A number of technically relevant polymeric systems were

  15. Oxidation of lignin and cellulose, humification and coalification

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Volborth, A.

    1976-06-09

    Oxygen plays an important role in the first stages of the decomposition of organic substances derived from plant material. The decomposition and reformation of such organic matter as cellulose and lignin leads, through-humification and a sequence of metamorphic processes, to the formation of coal. Initially, oxidation reactions cause the formation of dark-colored humic acids, later under more anaerobic conditions, pressure and higher temperatures, polymerization occurs as the sediment becomes buried. Under these conditions phenolic compounds are more stable, also during the processes of decomposition phenolic substances are more resistant to microorganisms, and thus seem to accumulate. The humification process maymore » be considered as the first step in coalification. It starts by rapid decomposition of the cellulose and by enzymatic degradation of the lignin of the rotting plant substance to form C/sub 6/-C/sub 3/ or C/sub 6/-C/sub 1/ compounds. These lose methoxyl groups and carboxyl groups and can form hydroquinones which may polymerize and combine, forming humic acids. Degradation may proceed also to aliphatic compounds. Most of the reactions seem to lead to benzoquinones which dimerize and polymerize further, causing an increase in aromatization with age, and under more anaerobic conditions later during coalification. When conditions become anaerobic, melanoidin and glucosamin compounds form and nitrogen fixation occurs. This explains the presence of about 1 to 3.5 percent nitrogen in humic acid concentrates, lignin, lignite, subbituminous and bituminous coal. The fixation of nitrogen also results in further reduction of carbon in humic substance during the later stages of humification. Further coalification of buried humified strata of decomposed organic material causes reduction as the methoxyl and oxygen group content decreases, and CO and CO/sub 2/ gases and H/sub 2/O evolve and gradual dehydration occurs.« less

  16. [The spectrum studies of structure characteristics in magma contact metamorphic coal].

    PubMed

    Wu, Dun; Sun, Ruo-Yu; Liu, Gui-Jian; Yuan, Zi-Jiao

    2013-10-01

    The structural parameters evolution of coal due to the influence of intrusions of hot magma was investigated and analyzed. X-ray diffraction and laser confocal microscope Raman spectroscopy were used to test and analyze 4 coal samples undergoing varying contact-metamorphism by igneous magmas in borehole No. 13-4 of Zhuji coal mine, Huainan coalfield. The result showed that coal XRD spectrum showed higher background intensity, with the 26 degrees and 42 degrees nearby apparent graphite diffraction peak. Two significant vibration peaks of coal Raman spectra were observed in the 1 000-2 000 cm(-1) frequency range: broad "D" peak at 1 328-1 369 cm(-1) and sharp "G" peak at 1 564-1 599 cm(-1). With the influence of magma intrusion, the relationship between coal structural parameters and coal ranks was excellent.

  17. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Nabeel, A.; Khan, M.A.; Husain, S.

    Coal is the most abundant source of energy. However, there is a need to develop cleaner, and more efficient, economical, and convenient coal conversion technologies. It is important to understand the organic chemical structure of coal for achieving real breakthroughs in the development of such coal conversion technologies. A novel computer-assisted modeling technique based on the analysis of {sup 13}C NMR and gel permeation chromatography has been applied to predict the average molecular structure of the acetylated product of a depolymerized bituminous Indian coal. The proposed molecular structure may be of practical use in understanding the mechanism of coal conversionsmore » during the processes of liquefaction, gasification, combustion, and carbonization.« less

  18. Royal Society, Discussion on New Coal Chemistry, London, England, May 21, 22, 1980, Proceedings

    NASA Astrophysics Data System (ADS)

    1981-03-01

    A discussion of new coal chemistry is presented. The chemical and physical structure of coal is examined in the first section, including structural studies of coal extracts, metal and metal complexes in coal and coal microporosity. The second section presents new advances in applied coal technology. The development of liquid fuels and chemicals from coal is given especial emphasis, with papers on the Sasol Synthol process, the Shell-Koppers gasification process, liquefaction and gasification in Germany, the Solvent Refined Coal process, the Exxon Donor Solvent liquefaction process and the Mobil Methanol-to-Gasoline process. Finally, some developments that will be part of the future of coal chemistry in the year 2000 are examined in the third section, including coal-based chemical complexes and the use of coal as an alternative source to oil for chemical feedstocks.

  19. Optimizing and Characterizing Geopolymers from Ternary Blend of Philippine Coal Fly Ash, Coal Bottom Ash and Rice Hull Ash

    PubMed Central

    Kalaw, Martin Ernesto; Culaba, Alvin; Hinode, Hirofumi; Kurniawan, Winarto; Gallardo, Susan; Promentilla, Michael Angelo

    2016-01-01

    Geopolymers are inorganic polymers formed from the alkaline activation of amorphous alumino-silicate materials resulting in a three-dimensional polymeric network. As a class of materials, it is seen to have the potential of replacing ordinary Portland cement (OPC), which for more than a hundred years has been the binder of choice for structural and building applications. Geopolymers have emerged as a sustainable option vis-à-vis OPC for three reasons: (1) their technical properties are comparable if not better; (2) they can be produced from industrial wastes; and (3) within reasonable constraints, their production requires less energy and emits significantly less CO2. In the Philippines, the use of coal ash, as the alumina- and silica- rich geopolymer precursor, is being considered as one of the options for sustainable management of coal ash generation from coal-fired power plants. However, most geopolymer mixes (and the prevalent blended OPC) use only coal fly ash. The coal bottom ash, having very few applications, remains relegated to dumpsites. Rice hull ash, from biomass-fired plants, is another silica-rich geopolymer precursor material from another significantly produced waste in the country with only minimal utilization. In this study, geopolymer samples were formed from the mixture of coal ash, using both coal fly ash (CFA) and coal bottom ash (CBA), and rice hull ash (RHA). The raw materials used for the geopolymerization process were characterized using X-ray fluorescence spectroscopy (XRF) for elemental and X-ray diffraction (XRD) for mineralogical composition. The raw materials’ thermal stability and loss on ignition (LOI) were determined using thermogravimetric analysis (TGA) and reactivity via dissolution tests and inductively-coupled plasma mass spectrometry (ICP) analysis. The mechanical, thermal and microstructural properties of the geopolymers formed were analyzed using compression tests, Fourier transform infra-red spectroscopy (FTIR), scanning electron microscopy (SEM) and thermogravimetric analysis (TGA). Using a Scheffé-based mixture design, targeting applications with low thermal conductivity, light weight and moderate strength and allowing for a maximum of five percent by mass of rice hull ash in consideration of the waste utilization of all three components, it has been determined that an 85-10-5 by weight ratio of CFA-CBA-RHA activated with 80-20 by mass ratio of 12 M NaOH and sodium silicate (55% H2O, modulus = 3) produced geopolymers with a compressive strength of 18.5 MPa, a volumetric weight of 1660 kg/m3 and a thermal conductivity of 0.457 W/m-°C at 28-day curing when pre-cured at 80 °C for 24 h. For this study, the estimates of embodied energy and CO2 were all below 1.7 MJ/kg and 0.12 kg CO2/kg, respectively. PMID:28773702

  20. Concept of a self-associated multimer structure of coal

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gagarin, S.G.; Krichko, A.A.

    1984-01-01

    The paper examines the role of donor-acceptor reaction in the binding of the individual components forming the structure of the organic coal mass, and analyses the manifestations of this reaction during liquefaction. The authors put forward the concept of self-associated polymers in the coal structure, in accordance with which the organic coal mass has spatial and energetic distribution of the donor and acceptor sectors of structure. It is the specific reaction between these which produces the necessary stability to the polymer system under normal conditions. The authors propose a mechanism for the action of solvents and various additives in themore » liquefaction of coal.« less

  1. [Roles of additives and surface control in slurry atomization

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tsai, S.C.

    1992-06-01

    As reported in the quarterly report of March of 1992, the relative viscosity of a Newtonian Coal Water Slurry (CWS) in the presence of an anionic polymeric dispersant is an order of magnitude higher than the prediction of the well established Krieger-Dougherty Equation which describes the relative viscosity of a non-aggregated Newtonian suspension as a function of particle volume fraction. Note that the anionic dispersant is used in such a quantity that the resulting interparticle electrostatic repulsion counter-balances the interparticle van der Waals attraction. Investigation continues to determine the mechanisms of such excess energy dissipation under shear. New experimental resultsmore » are presented in this report to verify the role of the anionic polymeric dispersant in such excess energy dissipation of CWS.« less

  2. [Roles of additives and surface control in slurry atomization]. Quarterly report

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tsai, S.C.

    1992-06-01

    As reported in the quarterly report of March of 1992, the relative viscosity of a Newtonian Coal Water Slurry (CWS) in the presence of an anionic polymeric dispersant is an order of magnitude higher than the prediction of the well established Krieger-Dougherty Equation which describes the relative viscosity of a non-aggregated Newtonian suspension as a function of particle volume fraction. Note that the anionic dispersant is used in such a quantity that the resulting interparticle electrostatic repulsion counter-balances the interparticle van der Waals attraction. Investigation continues to determine the mechanisms of such excess energy dissipation under shear. New experimental resultsmore » are presented in this report to verify the role of the anionic polymeric dispersant in such excess energy dissipation of CWS.« less

  3. Short residence time coal liquefaction process including catalytic hydrogenation

    DOEpatents

    Anderson, R.P.; Schmalzer, D.K.; Wright, C.H.

    1982-05-18

    Normally solid dissolved coal product and a distillate liquid product are produced by continuously passing a feed slurry comprising raw feed coal and a recycle solvent oil and/or slurry together with hydrogen to a preheating-reaction zone, the hydrogen pressure in the preheating-reaction zone being at least 1,500 psig (105 kg/cm[sup 2]), reacting the slurry in the preheating-reaction zone at a temperature in the range of between about 455 and about 500 C to dissolve the coal to form normally liquid coal and normally solid dissolved coal. A total slurry residence time is maintained in the reaction zone ranging from a finite value from about 0 to about 0.2 hour, and reaction effluent is continuously and directly contacted with a quenching fluid to substantially immediately reduce the temperature of the reaction effluent to below 425 C to substantially inhibit polymerization so that the yield of insoluble organic matter comprises less than 9 weight percent of said feed coal on a moisture-free basis. The reaction is performed under conditions of temperature, hydrogen pressure and residence time such that the quantity of distillate liquid boiling within the range C[sub 5]-454 C is an amount at least equal to that obtainable by performing the process under the same condition except for a longer total slurry residence time, e.g., 0.3 hour. Solvent boiling range liquid is separated from the reaction effluent and recycled as process solvent. The amount of solvent boiling range liquid is sufficient to provide at least 80 weight percent of that required to maintain the process in overall solvent balance. 6 figs.

  4. Short residence time coal liquefaction process including catalytic hydrogenation

    DOEpatents

    Anderson, Raymond P.; Schmalzer, David K.; Wright, Charles H.

    1982-05-18

    Normally solid dissolved coal product and a distillate liquid product are produced by continuously passing a feed slurry comprising raw feed coal and a recycle solvent oil and/or slurry together with hydrogen to a preheating-reaction zone (26, alone, or 26 together with 42), the hydrogen pressure in the preheating-reaction zone being at least 1500 psig (105 kg/cm.sup.2), reacting the slurry in the preheating-reaction zone (26, or 26 with 42) at a temperature in the range of between about 455.degree. and about 500.degree. C. to dissolve the coal to form normally liquid coal and normally solid dissolved coal. A total slurry residence time is maintained in the reaction zone ranging from a finite value from about 0 to about 0.2 hour, and reaction effluent is continuously and directly contacted with a quenching fluid (40, 68) to substantially immediately reduce the temperature of the reaction effluent to below 425.degree. C. to substantially inhibit polymerization so that the yield of insoluble organic matter comprises less than 9 weight percent of said feed coal on a moisture-free basis. The reaction is performed under conditions of temperature, hydrogen pressure and residence time such that the quantity of distillate liquid boiling within the range C.sub.5 -454.degree. C. is an amount at least equal to that obtainable by performing the process under the same condition except for a longer total slurry residence time, e.g., 0.3 hour. Solvent boiling range liquid is separated from the reaction effluent (83) and recycled as process solvent (16). The amount of solvent boiling range liquid is sufficient to provide at least 80 weight percent of that required to maintain the process in overall solvent balance.

  5. Identification of plant megafossils in Pennsylvanian-age coal

    USGS Publications Warehouse

    Winston, R.B.

    1989-01-01

    Criteria are provided for identification of certain Pennsylvanian-age plant megafossils directly from coal based on their characteristic anatomical structures as documented from etched polished coal surfaces in comparison with other modes of preservation. Lepidophloios hallii periderm, Diaphorodendron periderm, an Alethopteris pinnule, and a Cordaites leaf were studied in material in continuity with adjacent permineralized peat (carbonate coal-ballas). Calamites wood in attachment to a pitch cast and a Psaronius stem in coal in attachment to a fusinitized Psaronius inner root mantle were studied. Sigillaria was identified in coal by comparison to its structure in permineralized peat. Other plant tissues with characteristic structures were found but could not be attributed to specific plants. ?? 1989.

  6. Structural elucidation, molecular representation and solvent interactions of vitrinite-rich and inertinite-rich South African coals

    NASA Astrophysics Data System (ADS)

    van Niekerk, Daniel

    The structural differences and similarities of two Permian-aged South African coals, vitrinite-rich Waterberg and inertinite-rich Highveld coals (similar rank, carbon content and Permian age), were evaluated. With South African coals the opportunity presented itself to study not only Permian-aged Gondwana vitrinite but also inertinite. It was expected that these coals would differ from Northern hemisphere Carboniferous coals. It was concluded from various structural data that both coals, although different in maceral composition and depositional basins, are similar in their base structural composition. The main differences were that the inertinite-rich Highveld coal was more ordered, more aromatic, and had less hydrogen than the vitrinite-rich Waterberg coal. Analytical data were used to construct large-scale advanced molecular representations for vitrinite-rich Waterberg and inertinite-rich Highveld coals. The three-dimensional models were structurally diverse with a molecular weight range of 78 to 1900 amu. The vitrinite-rich coal model consisted of 18,572 atoms and 191 individual molecules and the inertinite-rich coal model consisted of 14,242 atoms and 158 individual molecules. This largescale modeling effort was enabled by the development of various PERL scripts to automate various visualization and analytical aspects. Coal swelling studies were conducted using the traditional pack-bed swelling method and a new novel single-particle stop-motion videography swelling method with NMP and CS2/NMP solvents. The pack-bed swelling showed that vitrinite-rich coal had a greater swelling extent and that swelling extent for both coals was greater in CS2/NMP binary solvent than for NMP. Single-particle swelling experiments showed that both coals, for both solvents, exhibit overshoot-type and climbing-type swelling behaviors. Inertinite-coal had a faster swelling rate, in both solvents, than the vitrinite-rich coal. The single-particle swelling data was used to calculate the kinetic parameters and it was found that the swelling was governed by relaxation of the coal structure (super-Case II swelling). X-ray computed tomography was conducted confirming anisotropic swelling. The petrographic transitions (maceral-group composition and reflectance) with solvent swelling and extraction were quantified. No changes in the maceral compositions were found, but changes in some coal particles were observed. Random reflectance analysis showed that, for both vitrinite and inertinite, there is a decrease in reflectance values with solvent treatment. Vitrinite reflectograms showed a shift from the dominant reflecting V-types to lower V-types. The inertinite reflectograms exhibited an increase in number of I-types (broadening of reflectrograms). Molecular simulation and visualization approaches to solvent swelling and extraction were performed on the proposed molecular models of vitrinite-rich and inertinite-rich coals. A theoretical extraction yield was determined using solubility parameters and showed agreement with experimental extraction yield trends. Statistical Associating Fluid Theory (SAFT) modeling was explored to test whether this method could predict swelling extent. The predicted swelling trends of SAFT were comparable to that of the experimental swelling results. SAFT was found to be a promising tool for solvent-coal interaction predictions. Partially solvent swollen structures were constructed by the addition of solvent molecules to the original coal molecules using a amorphous building approach. This method showed that coal-coal non-bonding interaction changed with the introduction of solvent. A disruption in the van der Waals interaction energies and a change in hydrogen bond distributions were observed in the swollen coal models and quantified. It was concluded that small changes in coal structure translates to significant changes in solvent interaction behavior. These changes were successfully visualized and simulated using atomistic molecular representations.

  7. Subtle structural influences on coal thickness and distribution: Examples from the Lower Broas-Stockton coal (Middle Pennsylvanian), Eastern Kentucky Coal Field, USA

    USGS Publications Warehouse

    Greb, S.F.; Eble, C.F.; Hower, J.C.

    2005-01-01

    The Lower Broas-Stockton coal is a heavily mined coal of the Central Appalachian Basin. Coal thickness, distribution, composition, and stratigraphic position were compared with basement structure, gas and oil field trends, and sequence strat- igraphic and paleoclimate interpretations to better understand the geology of the Stockton coal bed in eastern Kentucky. The thickest coal occurs south of the Warfield structural trend and east of the Paint Creek Uplift, two basement-related structures. Along the Warfield trend, coal beds in the underlying Peach Orchard coal zone locally merge with the Stockton coal to form a seam more than 3 m thick. Other areas of thick coal occur in elongate trends. Two pairs of elongate, conjugate trends in Stockton coal thickness are interpreted as regional paleofractures that influenced paleotopography and groundwater during peat accumulation. Compositional group analyses indicate that the Stockton peat infilled depressions in the paleotopography as a topogenous to soligenous mire codominated by tree ferns and lycopsid trees. Flooding from adjacent paleochannels is indicated by partings and seam splits along the margins of the mineable coal body. One or more increments of low-vitrinite coal, dominated by tree ferns and shrubby, Densosporites-producing lycopsids occur at all sample sites. Similar assemblages have been previously used to identify ombrogenous, domed mire origins for Early and Middle Pennsylvanian coals in which ash yields were less than 10%. It is difficult, however, to reconcile ombrogenous conditions with the partings in the Stockton coal in this area. Low-ash, low-vitrinite increments may have been formed in topogenous to soligenous mires with periodic drying or water-table fluctuations, rather than widespread doming. This is consistent with interpretations of increasingly seasonal paleoclimates in the late Middle and Late Pennsylvanian and fracture-influenced groundwater conditions. ??2005 Geological Society of America.

  8. Release behavior and formation mechanism of polycyclic aromatic hydrocarbons during coal pyrolysis.

    PubMed

    Gao, Meiqi; Wang, Yulong; Dong, Jie; Li, Fan; Xie, Kechang

    2016-09-01

    Polycyclic aromatic hydrocarbons (PAHs) are major environmental pollutants. They have attracted considerable attention due to their severe potential carcinogenic, mutagenic and genotoxic effects on human health. In this study, five different rank coals from China were pyrolyzed using pyro-probe CDS 5250 and the release behavior of 16 PAHs under different pyrolysis conditions were studied by Gas Chromatography-Mass Spectrometer (GC-MS). The structural characteristics of the five coals were determined by Cross-Polarization/Magic Angle Spinning Carbon-13 Nuclear Magnetic Resonance (CP/MAS (13)C NMR) spectroscopy, and then the factors influencing the formation of PAHs during coal pyrolysis were discussed together with the coal structural data. It was shown that the amount of PAHs generated during coal pyrolysis was largely related to coal rank and followed the order of medium metamorphic coal > low metamorphic coal > high metamorphic coal. The amount of total PAHs varied as the temperature was increased from 400 °C to 1200 °C, which showed a trend of first increasing and then decreasing, with the maximum value at 800 °C. Moreover, the species of PAHs released varied with pyrolysis temperatures. When the temperature was lower than 800 °C, the small ring PAHs were the most abundant, while the proportion of heavy rings increased at higher temperature. The results indicate that the formation of PAHs during coal pyrolysis depends on the structure of the coal. The species and amounts of PAHs generated during coal pyrolysis are closely related to the contents of protonated aromatic carbons and bridging ring junction aromatic carbons present in the coal structure. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. The effect of coal bed dewatering and partial oxidation on biogenic methane potential

    USGS Publications Warehouse

    Jones, Elizabeth J.P.; Harris, Steve H.; Barnhart, Elliott P.; Orem, William H.; Clark, Arthur C.; Corum, Margo D.; Kirshtein, Julie D.; Varonka, Matthew S.; Voytek, Mary A.

    2013-01-01

    Coal formation dewatering at a site in the Powder River Basin was associated with enhanced potential for secondary biogenic methane determined by using a bioassay. We hypothesized that dewatering can stimulate microbial activity and increase the bioavailability of coal. We analyzed one dewatered and two water-saturated coals to examine possible ways in which dewatering influences coal bed natural gas biogenesis by looking at differences with respect to the native coal microbial community, coal-methane organic intermediates, and residual coal oxidation potential. Microbial biomass did not increase in response to dewatering. Small Subunit rRNA sequences retrieved from all coals sampled represented members from genera known to be aerobic, anaerobic and facultatively anaerobic. A Bray Curtis similarity analysis indicated that the microbial communities in water-saturated coals were more similar to each other than to the dewatered coal, suggesting an effect of dewatering. There was a higher incidence of long chain and volatile fatty acid intermediates in incubations of the dewatered coal compared to the water-saturated coals, and this could either be due to differences in microbial enzymatic activities or to chemical oxidation of the coal associated with O2 exposure. Dilute H2O2 treatment of two fractions of structural coal (kerogen and bitumen + kerogen) was used as a proxy for chemical oxidation by O2. The dewatered coal had a low residual oxidation potential compared to the water-saturated coals. Oxidation with 5% H2O2 did increase the bioavailability of structural coal, and the increase in residual oxidation potential in the water saturated coals was approximately equivalent to the higher methanogenic potential measured in the dewatered coal. Evidence from this study supports the idea that coal bed dewatering could stimulate biogenic methanogenesis through partial oxidation of the structural organics in coal once anaerobic conditions are restored.

  10. Anomalous Hall conductivity and electronic structures of Si-substituted Mn2CoAl epitaxial films

    NASA Astrophysics Data System (ADS)

    Arima, K.; Kuroda, F.; Yamada, S.; Fukushima, T.; Oguchi, T.; Hamaya, K.

    2018-02-01

    We study anomalous Hall conductivity (σAHC) and electronic band structures of Si-substituted Mn2CoAl (Mn2CoAl1 -xSix ). First-principles calculations reveal that the electronic band structure is like a spin-gapless system even after substituting a quaternary element of Si for Al up to x =0.2 in Mn2CoAl1 -xSix . This means that the Si substitution enables the Fermi-level shift without largely changing the electronic structures in Mn2CoAl . By using molecular beam epitaxy techniques, Mn2CoAl1 -xSix epitaxial films can be grown, leading to the systematic control of x (0 ⩽x ⩽0.3 ). In addition to the electrical conductivity, the values of σAHC for the Mn2CoAl1 -xSix films are similar to those in Mn2CoAl films shown in previous reports. We note that a very small σAHC of ˜1.1 S/cm is obtained for x = 0.225, and the sign of σAHC is changed from positive to negative at around x = 0.25. We discuss the origin of the sign reversal of σAHC as a consequence of the Fermi-level shift in Mn2CoAl . Considering the presence of the structural disorder in the Mn2CoAl1 -xSix films, we can conclude that the small value and sign reversal of σAHC are not related to the characteristics of spin-gapless semiconductors.

  11. An investigation of the role of water on retrograde/condensation reactions and enhanced liquefaction yields. Quarterly progress report, January 1, 1994--March 31, 1994

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Miknis, F.P.; Netzel, D.A.

    The results of coal swelling measurements using 1,4-dioxane as the swelling reagent for premoisturized coals (raw) and coal dried thermally, chemically, and with microwave radiation are presented. An increase in the swelling ratio relative to raw coal indicates a decrease in the amount of cross-linking in the coal. Conversely, a decrease in the ratio indicates an increase in cross-linking. The extent of cross-linking (as measured by 1,4-dioxane) for Texas, Black Thunder, and Eagle Butte Coals are about the same. Illinois {number_sign}6 coal appears to have less cross-linking relative to the other three coals. These results are expected on the basismore » of coal rank. The increase in cross linking is most pronounced for coals dried thermally and with microwave radiation. A decrease in the swelling ratios for all four coals suggests that cross-linking had occurred possibly due to partial devolatilization process. However, low temperature, chemical dehydration of the coals causes only a small or no change in the internal structure for Texas and Illinois {number_sign}6 coals whereas a significant decrease in the cross-linking structure for the Black Thunder and Eagle Butte coals is observed. It is possible that the solvent (CH{sub 3}OH) and products resulting from the chemical dehydrating (acetone and methanol) occupy the surface sites that water had before the reaction and thus preventing cross-linking to occur. These reagents can also promote swelling of coals and may account for some of the decrease in the cross-linking of the coal structure observed for the chemically dried coals.« less

  12. Porous Structure Design of Polymeric Membranes for Gas Separation

    DOE PAGES

    Zhang, Jinshui; Schott, Jennifer Ann; Mahurin, Shannon Mark; ...

    2017-04-04

    High-performance polymeric membranes for gas separation are of interest for molecular-level separations in industrial-scale chemical, energy and environmental processes. To overcome the inherent trade-off relationship between permeability and selectivity, the creation of permanent microporosity in polymeric matrices is highly desirable because the porous structures can provide a high fractional free volume to facilitate gas transport through the dense layer. In this feature article, recent developments in the formation of porous polymeric membranes and potential strategies for pore structure design are reviewed.

  13. Evaluation of multiple-scale 3D characterization for coal physical structure with DCM method and synchrotron X-ray CT.

    PubMed

    Wang, Haipeng; Yang, Yushuang; Yang, Jianli; Nie, Yihang; Jia, Jing; Wang, Yudan

    2015-01-01

    Multiscale nondestructive characterization of coal microscopic physical structure can provide important information for coal conversion and coal-bed methane extraction. In this study, the physical structure of a coal sample was investigated by synchrotron-based multiple-energy X-ray CT at three beam energies and two different spatial resolutions. A data-constrained modeling (DCM) approach was used to quantitatively characterize the multiscale compositional distributions at the two resolutions. The volume fractions of each voxel for four different composition groups were obtained at the two resolutions. Between the two resolutions, the difference for DCM computed volume fractions of coal matrix and pores is less than 0.3%, and the difference for mineral composition groups is less than 0.17%. This demonstrates that the DCM approach can account for compositions beyond the X-ray CT imaging resolution with adequate accuracy. By using DCM, it is possible to characterize a relatively large coal sample at a relatively low spatial resolution with minimal loss of the effect due to subpixel fine length scale structures.

  14. Structural characterization of graphene layers in various Indian coals by X-Ray Diffraction technique

    NASA Astrophysics Data System (ADS)

    Manoj, B.; Kunjomana, A. G.

    2015-02-01

    The results of the structural investigation of three Indian coals showed that, the structural parameters like fa & Lc increased where as interlayer spacing d002 decreased with increase in carbon content, aromaticity and coal rank. These structural parameters change just opposite with increase in volatile matter content. Considering the 'turbostratic' structure for coals, the minimum separation between aromatic lamellae was found to vary between 3.34 to 3.61 A° for these coals. As the aromaticity increased, the interlayer spacing decreased an indication of more graphitization of the sample. Volatile matter and carbon content had a strong influence on the aromaticity, interlayer spacing and stacking height on the sample. The average number of carbon atoms per aromatic lamellae and number of layers in the lamellae was found to be 16-21 and 7-8 for all the samples.

  15. Acrylic esters in radiation polymerization

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Fomina, N.V.; Khoromskaya, V.A.; Shiryaeva, G.V.

    1988-03-01

    The radiation behavior of (meth)acrylic esters of varying structure was studied. It was shown that in radiation polymerization, in contrast to thermal polymerization, the structure of the ester part can significantly affect the reaction rate and capacity for polymerization in the presence of oxygen. The experimental data are explained from the point of view of consideration of nonvalence effects of the substitutent on the reactivity of the double bond.

  16. Structural basis of reverse nucleotide polymerization

    PubMed Central

    Nakamura, Akiyoshi; Nemoto, Taiki; Heinemann, Ilka U.; Yamashita, Keitaro; Sonoda, Tomoyo; Komoda, Keisuke; Tanaka, Isao; Söll, Dieter; Yao, Min

    2013-01-01

    Nucleotide polymerization proceeds in the forward (5′-3′) direction. This tenet of the central dogma of molecular biology is found in diverse processes including transcription, reverse transcription, DNA replication, and even in lagging strand synthesis where reverse polymerization (3′-5′) would present a “simpler” solution. Interestingly, reverse (3′-5′) nucleotide addition is catalyzed by the tRNA maturation enzyme tRNAHis guanylyltransferase, a structural homolog of canonical forward polymerases. We present a Candida albicans tRNAHis guanylyltransferase-tRNAHis complex structure that reveals the structural basis of reverse polymerization. The directionality of nucleotide polymerization is determined by the orientation of approach of the nucleotide substrate. The tRNA substrate enters the enzyme’s active site from the opposite direction (180° flip) compared with similar nucleotide substrates of canonical 5′-3′ polymerases, and the finger domains are on opposing sides of the core palm domain. Structural, biochemical, and phylogenetic data indicate that reverse polymerization appeared early in evolution and resembles a mirror image of the forward process. PMID:24324136

  17. Structural degradation of Thar lignite using MW1 fungal isolate: optimization studies

    USGS Publications Warehouse

    Haider, Rizwan; Ghauri, Muhammad A.; Jones, Elizabeth J.; Orem, William H.; SanFilipo, John R.

    2015-01-01

    Biological degradation of low-rank coals, particularly degradation mediated by fungi, can play an important role in helping us to utilize neglected lignite resources for both fuel and non-fuel applications. Fungal degradation of low-rank coals has already been investigated for the extraction of soil-conditioning agents and the substrates, which could be subjected to subsequent processing for the generation of alternative fuel options, like methane. However, to achieve an efficient degradation process, the fungal isolates must originate from an appropriate coal environment and the degradation process must be optimized. With this in mind, a representative sample from the Thar coalfield (the largest lignite resource of Pakistan) was treated with a fungal strain, MW1, which was previously isolated from a drilled core coal sample. The treatment caused the liberation of organic fractions from the structural matrix of coal. Fungal degradation was optimized, and it showed significant release of organics, with 0.1% glucose concentration and 1% coal loading ratio after an incubation time of 7 days. Analytical investigations revealed the release of complex organic moieties, pertaining to polyaromatic hydrocarbons, and it also helped in predicting structural units present within structure of coal. Such isolates, with enhanced degradation capabilities, can definitely help in exploiting the chemical-feedstock-status of coal.

  18. Fabrication and Optimal Design of Biodegradable Polymeric Stents for Aneurysms Treatments

    PubMed Central

    Han, Xue; Wu, Xia; Kelly, Michael; Chen, Xiongbiao

    2017-01-01

    An aneurysm is a balloon-like bulge in the wall of blood vessels, occurring in major arteries of the heart and brain. Biodegradable polymeric stent-assisted coiling is expected to be the ideal treatment of wide-neck complex aneurysms. This paper presents the development of methods to fabricate and optimally design biodegradable polymeric stents for aneurysms treatment. Firstly, a dispensing-based rapid prototyping (DBRP) system was developed to fabricate coil and zigzag structures of biodegradable polymeric stents. Then, compression testing was carried out to characterize the radial deformation of the stents fabricated with the coil or zigzag structure. The results illustrated the stent with a zigzag structure has a stronger radial stiffness than the one with a coil structure. On this basis, the stent with a zigzag structure was chosen for the development of a finite element model for simulating the real compression tests. The result showed the finite element model of biodegradable polymeric stents is acceptable within a range of radial deformation around 20%. Furthermore, the optimization of the zigzag structure was performed with ANSYS DesignXplorer, and the results indicated that the total deformation could be decreased by 35.7% by optimizing the structure parameters, which would represent a significant advance of the radial stiffness of biodegradable polymeric stents. PMID:28264515

  19. Use of overburden rocks from open-pit coal mines and waste coals of Western Siberia for ceramic brick production with a defect-free structure

    NASA Astrophysics Data System (ADS)

    Stolboushkin, A. Yu; Ivanov, A. I.; Storozhenko, G. I.; Syromyasov, V. A.; Akst, D. V.

    2017-09-01

    The rational technology for the production of ceramic bricks with a defect-free structure from coal mining and processing wastes was developed. The results of comparison of physical and mechanical properties and the structure of ceramic bricks manufactured from overburden rocks and waste coal with traditional for semi-dry pressing mass preparation and according to the developed method are given. It was established that a homogeneous, defect-free brick texture obtained from overburden rocks of open-pit mines and waste coal improves the quality of ceramic wall materials produced by the method of compression molding by more than 1.5 times compared to the brick with a traditional mass preparation.

  20. A Course in Fundamentals of Coal Utilization and Conversion Processes.

    ERIC Educational Resources Information Center

    Radovic, Ljubisa R.

    1985-01-01

    Describes the content, objectives, and requirements for a one-semester (30 20-hour sessions) graduate engineering course at the University of Concepcion, Chile. Major course topics include: structure and properties of coal; coal pyrolysis and carbonization; coal liquefaction; coal combustion and gasification; and economic and environmental…

  1. New maps of Federal coal ( USA).

    USGS Publications Warehouse

    Wayland, R.G.

    1981-01-01

    Compilation and analysis of publicly available data on Federal coal are resulting in voluminous map sets showing coal isopachs, structure contours, and overburden isopachs on each known minable coal bed. As of spring 1981, there are available from the US Geological Survey Open-File Services Section in Denver map sets at 1:24 000 scale or microfiche sets covering approximately 470 of the ultimately 1400 quadrangles in the program. A typical map set has a short text and about 20 plates, including a data sheet; a Federal mineral ownership map; and correlation charts. For each coal bed, there are isopachs, structure contours, stripping limits, and mining ratios extending as far as the data will permit, regardless of coal ownership. Reserve base tonnages and relative development potentials are calculated, but only for unleased Federal coal areas. -from Author

  2. Sulfur compounds in coal

    NASA Technical Reports Server (NTRS)

    Attar, A.; Corcoran, W. H.

    1977-01-01

    The literature on the chemical structure of the organic sulfur compounds (or functional groups) in coal is reviewed. Four methods were applied in the literature to study the sulfur compounds in coal: direct spectrometric and chemical analysis, depolymerization in drastic conditions, depolymerization in mild conditions, and studies on simulated coal. The data suggest that most of the organic sulfur in coal is in the form of thiophenic structures and aromatic and aliphatic sulfides. The relative abundance of the sulfur groups in bituminous coal is estimated as 50:30:20%, respectively. The ratio changes during processing and during the chemical analysis. The main effects are the transformation during processing of sulfides to the more stable thiophenic compounds and the elimination of hydrogen sulfide.

  3. Low-rank coal oil agglomeration

    DOEpatents

    Knudson, Curtis L.; Timpe, Ronald C.

    1991-01-01

    A low-rank coal oil agglomeration process. High mineral content, a high ash content subbituminous coals are effectively agglomerated with a bridging oil which is partially water soluble and capable of entering the pore structure, and usually coal derived.

  4. Low-rank coal oil agglomeration

    DOEpatents

    Knudson, C.L.; Timpe, R.C.

    1991-07-16

    A low-rank coal oil agglomeration process is described. High mineral content, a high ash content subbituminous coals are effectively agglomerated with a bridging oil which is partially water soluble and capable of entering the pore structure, and is usually coal-derived.

  5. Large-scale filament formation inhibits the activity of CTP synthetase

    PubMed Central

    Barry, Rachael M; Bitbol, Anne-Florence; Lorestani, Alexander; Charles, Emeric J; Habrian, Chris H; Hansen, Jesse M; Li, Hsin-Jung; Baldwin, Enoch P; Wingreen, Ned S; Kollman, Justin M; Gitai, Zemer

    2014-01-01

    CTP Synthetase (CtpS) is a universally conserved and essential metabolic enzyme. While many enzymes form small oligomers, CtpS forms large-scale filamentous structures of unknown function in prokaryotes and eukaryotes. By simultaneously monitoring CtpS polymerization and enzymatic activity, we show that polymerization inhibits activity, and CtpS's product, CTP, induces assembly. To understand how assembly inhibits activity, we used electron microscopy to define the structure of CtpS polymers. This structure suggests that polymerization sterically hinders a conformational change necessary for CtpS activity. Structure-guided mutagenesis and mathematical modeling further indicate that coupling activity to polymerization promotes cooperative catalytic regulation. This previously uncharacterized regulatory mechanism is important for cellular function since a mutant that disrupts CtpS polymerization disrupts E. coli growth and metabolic regulation without reducing CTP levels. We propose that regulation by large-scale polymerization enables ultrasensitive control of enzymatic activity while storing an enzyme subpopulation in a conformationally restricted form that is readily activatable. DOI: http://dx.doi.org/10.7554/eLife.03638.001 PMID:25030911

  6. Peat in modern swamps mimics coal origins 300 M years ago

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Given, P.H.; Ryan, N.J.; Rhoads, C.A.

    1985-07-01

    Peat swamps can provide excellent models of ancient coal-forming processes. Peats of differing salinity and vegetational cover exhibit different trends of chemistry with depth, which have been studied in order to clarify ideas of coal origins. Thus changes with depth of phenolic structures determined by pyrolysis/gas chromatography/mass spectrometry reflect changes in plant source and partial microbial degradation of lignin, which will be reflected in the structure of coals that may form later. 12 refs., 3 figs.

  7. 30 CFR 800.17 - Bonding requirements for underground coal mines and long-term coal-related surface facilities and...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Bonding requirements for underground coal mines and long-term coal-related surface facilities and structures. 800.17 Section 800.17 Mineral Resources... REQUIREMENTS FOR SURFACE COAL MINING AND RECLAMATION OPERATIONS BOND AND INSURANCE REQUIREMENTS FOR SURFACE...

  8. 30 CFR 800.17 - Bonding requirements for underground coal mines and long-term coal-related surface facilities and...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 3 2012-07-01 2012-07-01 false Bonding requirements for underground coal mines and long-term coal-related surface facilities and structures. 800.17 Section 800.17 Mineral Resources... REQUIREMENTS FOR SURFACE COAL MINING AND RECLAMATION OPERATIONS BOND AND INSURANCE REQUIREMENTS FOR SURFACE...

  9. 30 CFR 800.17 - Bonding requirements for underground coal mines and long-term coal-related surface facilities and...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 3 2013-07-01 2013-07-01 false Bonding requirements for underground coal mines and long-term coal-related surface facilities and structures. 800.17 Section 800.17 Mineral Resources... REQUIREMENTS FOR SURFACE COAL MINING AND RECLAMATION OPERATIONS BOND AND INSURANCE REQUIREMENTS FOR SURFACE...

  10. 30 CFR 800.17 - Bonding requirements for underground coal mines and long-term coal-related surface facilities and...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 3 2014-07-01 2014-07-01 false Bonding requirements for underground coal mines and long-term coal-related surface facilities and structures. 800.17 Section 800.17 Mineral Resources... REQUIREMENTS FOR SURFACE COAL MINING AND RECLAMATION OPERATIONS BOND AND INSURANCE REQUIREMENTS FOR SURFACE...

  11. 30 CFR 800.17 - Bonding requirements for underground coal mines and long-term coal-related surface facilities and...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 3 2011-07-01 2011-07-01 false Bonding requirements for underground coal mines and long-term coal-related surface facilities and structures. 800.17 Section 800.17 Mineral Resources... REQUIREMENTS FOR SURFACE COAL MINING AND RECLAMATION OPERATIONS BOND AND INSURANCE REQUIREMENTS FOR SURFACE...

  12. 78 FR 14115 - Notice of Invitation To Participate; Coal Exploration License Application WYW181224, WY

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-04

    ... amended by the Federal Coal Leasing Amendments Act of 1976, and to Bureau of Land Management (BLM... structural and quality information of the coal. The BLM regulations at 43 CFR 3410 require the publication of an invitation to participate in the coal exploration in the Federal Register. The Federal coal...

  13. 76 FR 31626 - Notice of Invitation To Participate; Coal Exploration License Application WYW180006, WY

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-01

    ... amended by the Federal Coal Leasing Amendments Act of 1976, and to Bureau of Land Management (BLM... structural and quality information about the coal. The BLM regulations at 43 CFR 3410 require the publication of an invitation to participate in the coal exploration in the Federal Register. The Federal coal...

  14. Material and structural characterization of alkali activated low-calcium brown coal fly ash.

    PubMed

    Skvára, Frantisek; Kopecký, Lubomír; Smilauer, Vít; Bittnar, Zdenek

    2009-09-15

    The waste low-calcium Czech brown coal fly ash represents a considerable environmental burden due to the quantities produced and the potentially high content of leachable heavy metals. The heterogeneous microstucture of the geopolymer M(n) [-(Si-O)(z)-Al-O](n).wH(2)O, that forms during the alkaline activation, was examined by means of microcalorimetry, XRD, TGA, DSC, MIP, FTIR, NMR MAS ((29)Si, (27)Al, (23)Na), ESEM, EDS, and EBSD. The leaching of heavy metals and the evolution of compressive strength were also monitored. The analysis of raw fly ash identified a number of different morphologies, unequal distribution of elements, Fe-rich rim, high internal porosity, and minor crystalline phases of mullite and quartz. Microcalorimetry revealed exothermic reactions with dependence on the activator alkalinity. The activation energy of the geopolymerization process was determined as 86.2kJ/mol. The X-ray diffraction analysis revealed no additional crystalline phases associated with geopolymer formation. Over several weeks, the (29)Si NMR spectrum testified a high degree of polymerization and Al penetration into the SiO(4) tetrahedra. The (23)Na NMR MAS spectrum hypothesized that sodium is bound in the form of Na(H(2)O)(n) rather than Na(+), thus causing efflorescence in a moisture-gradient environment. As and Cr(6+) are weakly bonded in the geopolymer matrix, while excellent immobilization of Zn(2+), Cu(2+), Cd(2+), and Cr(3+) are reported.

  15. Effects of water saturation on P-wave propagation in fractured coals: An experimental perspective

    NASA Astrophysics Data System (ADS)

    Liu, Jie; Liu, Dameng; Cai, Yidong; Gan, Quan; Yao, Yanbin

    2017-09-01

    Internal structure of coalbed methane (CBM) reservoirs can be evaluated through ultrasonic measurements. The compressional wave that propagates in a fractured coal reservoir may indicate the internal coal structure and fluid characteristics. The P-wave propagation was proposed to study the relations between petrophysical parameters (including water saturation, fractures, porosity and permeability) of coals and the P-wave velocity (Vp), using a KON-NM-4A ultrasonic velocity meter. In this study, the relations between Vps and water saturations were established: Type I is mainly controlled by capillary of developed seepage pores. The controlling factors on Type II and Type III are internal homogeneity of pores/fractures and developed micro-fractures, respectively. Micro-fractures density linearly correlates with the Vp due to the fracture volume and dispersion of P-wave; and micro-fractures of types C and D have a priority in Vp. For dry coals, no clear relation exists between porosity, permeability and the Vp. However, as for water-saturated coals, the correlation coefficients of porosity, permeability and Vp are slightly improved. The Vp of saturated coals could be predicted with the equation of Vp-saturated = 1.4952Vp-dry-26.742 m/s. The relation between petrophysical parameters of coals and Vp under various water saturations can be used to evaluate the internal structure in fractured coals. Therefore, these relations have significant implications for coalbed methane (CBM) exploration.

  16. Porous polymer networks and ion-exchange media and metal-polymer composites made therefrom

    DOEpatents

    Kanatzidis, Mercouri G; Katsoulidis, Alexandros

    2015-03-10

    Porous polymeric networks and composite materials comprising metal nanoparticles distributed in the polymeric networks are provided. Also provided are methods for using the polymeric networks and the composite materials in liquid- and vapor-phase waste remediation applications. The porous polymeric networks, are highly porous, three-dimensional structures characterized by high surface areas. The polymeric networks comprise polymers polymerized from aldehydes and phenolic molecules.

  17. Porous polymer networks and ion-exchange media and metal-polymer composites made therefrom

    DOEpatents

    Kanatzidis, Mercouri G.; Katsoulidis, Alexandros

    2016-10-18

    Porous polymeric networks and composite materials comprising metal nanoparticles distributed in the polymeric networks are provided. Also provided are methods for using the polymeric networks and the composite materials in liquid- and vapor-phase waste remediation applications. The porous polymeric networks, are highly porous, three-dimensional structures characterized by high surface areas. The polymeric networks comprise polymers polymerized from aldehydes and phenolic molecules.

  18. [Identification of the cumulative eco-environment effect of coal-electricity integration based on interpretative structural model].

    PubMed

    Han, Lin Wei; Fu, Xiao; Yan, Yan; Wang, Chen Xing; Wu, Gang

    2017-05-18

    In order to determine the cumulative eco-environmental effect of coal-electricity integration, we selected 29 eco-environmental factors including different development and construction activities of coal-electricity integration, soil, water, atmospheric conditions, biology, landscape, and ecology. Literature survey, expert questionnaire and interview were conducted to analyze the interactive relationships between different factors. The structure and correlations between the eco-environmental factors influenced by coal-electricity integration activities were analyzed using interpretive structural modeling (ISM) and the cumulative eco-environment effect of development and construction activities was determined. A research and evaluation framework for the cumulative eco-environmental effect was introduced in addition to specific evaluation and management needs. The results of this study would provide a theoretical and technical basis for planning and management of coal-electricity integration development activities.

  19. Research on the Composition and Distribution of Organic Sulfur in Coal.

    PubMed

    Zhang, Lanjun; Li, Zenghua; Yang, Yongliang; Zhou, Yinbo; Li, Jinhu; Si, Leilei; Kong, Biao

    2016-05-13

    The structure and distribution of organic sulfur in coals of different rank and different sulfur content were studied by combining mild organic solvent extraction with XPS technology. The XPS results have shown that the distribution of organic sulfur in coal is related to the degree of metamorphism of coal. Namely, thiophenic sulfur content is reduced with decreasing metamorphic degree; sulfonic acid content rises with decreasing metamorphic degree; the contents of sulfate sulfur, sulfoxide and sulfone are rarely related with metamorphic degree. The solvent extraction and GC/MS test results have also shown that the composition and structure of free and soluble organic sulfur small molecules in coal is closely related to the metamorphic degree of coal. The free organic sulfur small molecules in coal of low metamorphic degree are mainly composed of aliphatic sulfides, while those in coal of medium and high metamorphic degree are mainly composed of thiophenes. Besides, the degree of aromatization of organic sulfur small molecules rises with increasing degree of coalification.

  20. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chunshan Song; Hatcher, P.G.; Saini, A.K.

    It has been indicated by DOE COLIRN panel that low-temperature catalytic pretreatment is a promising approach to the development of an improved liquefaction process. This work is a fundamental study on effects of pretreatments on coal structure and reactivity in liquefaction. The main objectives of this project are to study the coal structural changes induced by low-temperature catalytic and thermal pretreatments by using spectroscopic techniques; and to clarify the pretreatment-induced changes in reactivity or convertibility of coals. As the second volume of the final report, here we summarize our work on spectroscopic characterization of four raw coals including two subbituminousmore » coals and two bituminous coals, tetrahydrofuran (THF)-extracted but unreacted coals, the coals (THF-insoluble parts) that have been thermally pretreated. in the absence of any solvents and in the presence of either a hydrogen-donor solvent or a non-donor solvent, and the coals (THF-insoluble parts) that have been catalytically pretreated in the presence of a dispersed Mo sulfide catalyst in the absence of any solvents and in the presence of either a hydrogen-donor solvent or a non-donor solvent.« less

  1. Characteristics of Pyrolytic Topping in Fluidized Bed for Different Volatile Coals

    NASA Astrophysics Data System (ADS)

    Xiong, R.; Dong, L.; Xu, G. W.

    Coal is generally combusted or gasified directly to destroy completely the chemical structures, such as aromatic rings containing in volatile coals including bituminite and lignite. Coal topping refers to a process that extracts chemicals with aromatic rings from such volatile coals in advance of combustion or gasification and thereby takes advantage of the value of coal as a kind of chemical structure resource. CFB boiler is the coal utilization facility that can be easily retrofitted to implement coal topping. A critical issue for performing coal topping is the choice of the pyrolytic reactor that can be different types. The present study concerns fluidized bed reactor that has rarely been tested for use in coal topping. Two different types of coals, one being Xiaolongtan (XLT) lignite and the other Shanxi (SX) bituminous, were tested to clarify the yield and composition of pyrolysis liquid and gas under conditions simulating actual operations. The results showed that XLT lignite coals had the maximum tar yield in 823-873K and SX bituminite realized its highest tar yield in 873-923K. Overall, lignite produced lower tar yield than bituminous coal. The pyrolysis gas from lignite coals contained more CO and CO2 and less CH4, H2 and C2+C3 (C2H4, C2H6, C3H6, C3H8) components comparing to that from bituminous coal. TG-FTIR analysis of tars demonstrated that for different coals there are different amounts of typical chemical species. Using coal ash of CFB boiler, instead of quartz sand, as the fluidized particles decreased the yields of both tar and gas for all the tested coals. Besides, pyrolysis in a reaction atmosphere simulating the pyrolysis gas (instead of N2) resulted also in higher production of pyrolysis liquid.

  2. Investigation on the Activity Activation and Cementitious Property of Coal Gangue with High Iron and Silica Contents

    NASA Astrophysics Data System (ADS)

    Wu, Hong; Li, Yu; Teng, Min; Yang, Yu

    2017-11-01

    The activity of coal gangue by thermal activation and composite activation technologies was investigated. The crystal composition, framework structure and morphology change were analyzed by XRD, FT-IR and SEM, respectively. The cementitious property of coal gangue was measured by strength test. The results showed that thermal activation decomposed kaolinite in coal gangue, and formed the metastable structure with a porous state, multiple internal broken bonds and large specific surface areas. Based on thermal activation, the added lime provided the alkaline environment, then this reduced the bond energy of reactant particles and the degree of crystallinity of quartz in coal gangue. The two activation methods could effectively improve the cementitious property of coal gangue based unburned bricks, and that the composite activation technology was superior performance.

  3. Pyrolysis g.c.-m.s. of a series of degraded woods and coalified logs that increase in rank from peat to subbituminous coal

    USGS Publications Warehouse

    Hatcher, P.G.; Lerch, H. E.; Kotra, R.K.; Verheyen, T.V.

    1988-01-01

    Xylem tissue from degraded wood and coalified logs or stems was examined by pyrolysis g.c.-m.s. to improve understanding of the coalification process. The pyrolysis data, when combined with solid-state 13C n.m.r. data for the same samples, show several stages of evolution during coalification. The first stage, microbial degradation in peat, involves the selective degradation of cellulosic components and preservation of lignin-like components. As coalification increases, the lignin structural units undergo a series of defunctionalization reactions. The first of these involve loss of methoxyl groups, with replacement by phenolic hydroxyls such that catechol-like structures are produced. As the xylem tissue is converted to subbituminous coal, the persistence of phenols and methylated phenols in pyrolysis g.c.-m.s. data of subbituminous coal suggests that the catechol-like structures are being converted to phenol-like structures. The ability to discern detailed changes in the chemical structural composition of a genetically and histologically related series of samples provides an ideal method for developing models of coal structure, especially that of low-rank coal. ?? 1988.

  4. Comprehensive Fractal Description of Porosity of Coal of Different Ranks

    PubMed Central

    Ren, Jiangang; Zhang, Guocheng; Song, Zhimin; Liu, Gaofeng; Li, Bing

    2014-01-01

    We selected, as the objects of our research, lignite from the Beizao Mine, gas coal from the Caiyuan Mine, coking coal from the Xiqu Mine, and anthracite from the Guhanshan Mine. We used the mercury intrusion method and the low-temperature liquid nitrogen adsorption method to analyze the structure and shape of the coal pores and calculated the fractal dimensions of different aperture segments in the coal. The experimental results show that the fractal dimension of the aperture segment of lignite, gas coal, and coking coal with an aperture of greater than or equal to 10 nm, as well as the fractal dimension of the aperture segment of anthracite with an aperture of greater than or equal to 100 nm, can be calculated using the mercury intrusion method; the fractal dimension of the coal pore, with an aperture range between 2.03 nm and 361.14 nm, can be calculated using the liquid nitrogen adsorption method, of which the fractal dimensions bounded by apertures of 10 nm and 100 nm are different. Based on these findings, we defined and calculated the comprehensive fractal dimensions of the coal pores and achieved the unity of fractal dimensions for full apertures of coal pores, thereby facilitating, overall characterization for the heterogeneity of the coal pore structure. PMID:24955407

  5. Effect of temperature on the permeability of gas adsorbed coal under triaxial stress conditions

    NASA Astrophysics Data System (ADS)

    Li, Xiangchen; Yan, Xiaopeng; Kang, Yili

    2018-04-01

    The combined effects of gas sorption, stress and temperature play a significant role in the changing behavior of gas permeability in coal seams. The effect of temperature on nitrogen and methane permeability of naturally fractured coal is investigated. Coal permeability, P-wave velocity and axial strain were simultaneously measured under two effective stresses and six different temperatures. The results showed that the behavior of nitrogen and methane permeability presented nonmonotonic changes with increasing temperature. The variation in the P-wave velocity and axial strain showed a good correspondence with coal permeability. A higher effective stress limited the bigger deformation and caused the small change in permeability. Methane adsorption and desorption significantly influence the mechanical properties of coal and play an important role in the variations in coal permeability. The result of coal permeability during a complete stress-strain process showed that the variation in permeability is determined by the evolution of the internal structure. The increase in the temperature of the gas saturated coal causes the complex interaction between matrix swelling, matrix shrinkage and micro-fracture generation, which leads to the complex changes in coal structure and permeability. These results are helpful to understand the gas transport mechanism for exploiting coal methane by heat injection.

  6. Exploring the formation and electronic structure properties of the g-C3N4 nanoribbon with density functional theory

    NASA Astrophysics Data System (ADS)

    Wu, Hong-Zhang; Zhong, Qing-Hua; Bandaru, Sateesh; Liu, Jin; Lau, Woon Ming; Li, Li-Li; Wang, Zhenling

    2018-04-01

    The optical properties and condensation degree (structure) of polymeric g-C3N4 depend strongly on the process temperature. For polymeric g-C3N4, its structure and condensation degree depend on the structure of molecular strand(s). Here, the formation and electronic structure properties of the g-C3N4 nanoribbon are investigated by studying the polymerization and crystallinity of molecular strand(s) employing first-principle density functional theory. The calculations show that the width of the molecular strand has a significant effect on the electronic structure of polymerized and crystallized g-C3N4 nanoribbons, a conclusion which would be indirect evidence that the electronic structure depends on the structure of g-C3N4. The edge shape also has a distinct effect on the electronic structure of the crystallized g-C3N4 nanoribbon. Furthermore, the conductive band minimum and valence band maximum of the polymeric g-C3N4 nanoribbon show a strong localization, which is in good agreement with the quasi-monomer characters. In addition, molecular strands prefer to grow along the planar direction on graphene. These results provide new insight on the properties of the g-C3N4 nanoribbon and the relationship between the structure and properties of g-C3N4.

  7. Exploring the formation and electronic structure properties of the g-C3N4 nanoribbon with density functional theory.

    PubMed

    Wu, Hong-Zhang; Zhong, Qing-Hua; Bandaru, Sateesh; Liu, Jin; Lau, Woon Ming; Li, Li-Li; Wang, Zhenling

    2018-04-18

    The optical properties and condensation degree (structure) of polymeric g-C 3 N 4 depend strongly on the process temperature. For polymeric g-C 3 N 4 , its structure and condensation degree depend on the structure of molecular strand(s). Here, the formation and electronic structure properties of the g-C 3 N 4 nanoribbon are investigated by studying the polymerization and crystallinity of molecular strand(s) employing first-principle density functional theory. The calculations show that the width of the molecular strand has a significant effect on the electronic structure of polymerized and crystallized g-C 3 N 4 nanoribbons, a conclusion which would be indirect evidence that the electronic structure depends on the structure of g-C 3 N 4 . The edge shape also has a distinct effect on the electronic structure of the crystallized g-C 3 N 4 nanoribbon. Furthermore, the conductive band minimum and valence band maximum of the polymeric g-C 3 N 4 nanoribbon show a strong localization, which is in good agreement with the quasi-monomer characters. In addition, molecular strands prefer to grow along the planar direction on graphene. These results provide new insight on the properties of the g-C 3 N 4 nanoribbon and the relationship between the structure and properties of g-C 3 N 4 .

  8. Coalbed gas potential in the Pittsburgh-Huntington synclinorium, northern West Virginia

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Patchen, D.G.; Schwietering, J.F.; Repine, T.E.

    1991-03-01

    The West Virginia Geological and Economic Survey (WVGES) received a subcontract from the Texas Bureau of Economic Geology to conduct a geologic evaluation of critical production parameters for coalbed methane resources in the northern Appalachian coal basin. The study area is a northeast-southwest-trending ellipse that coincides with the axis of the Pittsburgh-Huntington Synclinorium in north central West Virginia and southwestern Pennsylvania. Coalbed gas resources there have been estimated to be 61 bcf in previous work funded by the Gas Research institute. Data used in that study were mainly core descriptions and drillers' logs from coal exploration cores. The current researchmore » will integrate data from the WVGES' coal, oil and gas, and ground water databases to more carefully determine the number and thicknesses of coals below the Pittsburgh, and their hydrologic setting. Main objectives are to determine: the number of coals present; the geographic and stratigraphic positions of the thickest coals; locations of depocenters with stacked coals; the pressure regime of the area and geologic factors contributing to it; ground-water circulation patterns; and the presence of any potentiometric anomalies. Local and regional stratigraphic and structural cross sections and lithofacies and coal occurrence maps will be made for the coal-bearing interval below the Pittsburgh coal to show the distribution, structural attitude, and depositional systems. Regional and local control of structural elements, including fractures, on gas producibility from coalbeds will be determined. Gas and water production data will be collected from two small areas of current production and mapped and compared to maps of geologic parameters. The goal is to measure the effect on production of geologic parameters in these coalbed gas fields, and determine the locations of other 'sweet spots' in these coal beds.« less

  9. Polymerization in the gas phase, in clusters, and on nanoparticle surfaces.

    PubMed

    El-Shall, M Samy

    2008-07-01

    Gas phase and cluster experiments provide unique opportunities to quantitatively study the effects of initiators, solvents, chain transfer agents, and inhibitors on the mechanisms of polymerization. Furthermore, a number of important phenomena, unique structures, and novel properties may exist during gas-phase and cluster polymerization. In this regime, the structure of the growing polymer may change dramatically and the rate coefficient may vary significantly upon the addition of a single molecule of the monomer. These changes would be reflected in the properties of the oligomers deposited from the gas phase. At low pressures, cationic and radical cationic polymerizations may proceed in the gas phase through elimination reactions. In the same systems at high pressure, however, the ionic intermediates may be stabilized, and addition without elimination may occur. In isolated van der Waals clusters of monomer molecules, sequential polymerization with several condensation steps can occur on a time scale of a few microseconds following the ionization of the gas-phase cluster. The cluster reactions, which bridge gas-phase and condensed-phase chemistry, allow examination of the effects of controlled states of aggregation. This Account describes several examples of gas-phase and cluster polymerization studies where the most significant results can be summarized as follows: (1) The carbocation polymerization of isobutene shows slower rates with increasing polymerization steps resulting from entropy barriers, which could explain the need for low temperatures for the efficient propagation of high molecular weight polymers. (2) Radical cation polymerization of propene can be initiated by partial charge transfer from an ionized aromatic molecule such as benzene coupled with covalent condensation of the associated propene molecules. This novel mechanism leads exclusively to the formation of propene oligomer ions and avoids other competitive products. (3) Structural information on the oligomers formed by gas-phase polymerization can be obtained using the mass-selected ion mobility technique where the measured collision cross-sections of the selected oligomer ions and collision-induced dissociation can provide fairly accurate structural identifications. The identification of the structures of the dimers and trimers formed in the gas-phase thermal polymerization of styrene confirms that the polymerization proceeds according to the Mayo mechanism. Similarly, the ion mobility technique has been utilized to confirm the formation of benzene cations by intracluster polymerization following the ionization of acetylene clusters. Finally, it has been shown that polymerization of styrene vapor on the surface of activated nanoparticles can lead to the incorporation of a variety of metal and metal oxide nanoparticles within polystyrene films. The ability to probe the reactivity and structure of the small growing oligomers in the gas phase can provide fundamental insight into mechanisms of polymerization that are difficult to obtain from condensed-phase studies. These experiments are also important for understanding the growth mechanisms of complex organics in flames, combustion processes, interstellar clouds, and solar nebula where gas-phase reactions, cluster polymerization, and surface catalysis on dust nanoparticles represent the major synthetic pathways. This research can lead to the discovery of novel initiation mechanisms and reaction pathways with applications in the synthesis of oligomers and nanocomposites with unique and improved properties.

  10. Nanoscale High Energetic Materials: A Polymeric Nitrogen Chain N8 Confined inside a Carbon Nanotube

    NASA Astrophysics Data System (ADS)

    Abou-Rachid, Hakima; Hu, Anguang; Timoshevskii, Vladimir; Song, Yanfeng; Lussier, Louis-Simon

    2008-05-01

    We present a theoretical study of a new hybrid material, nanostructured polymeric nitrogen, where a polymeric nitrogen chain is encapsulated in a carbon nanotube. The electronic and structural properties of the new system are studied by means of ab initio electronic structure and molecular dynamics calculations. Finite temperature simulations demonstrate the stability of this nitrogen phase at ambient pressure and room temperature using carbon nanotube confinement. This nanostructured confinement may open a new path towards stabilizing polynitrogen or polymeric nitrogen at ambient conditions.

  11. Click polymerization for the synthesis of reduction-responsive polymeric prodrug

    NASA Astrophysics Data System (ADS)

    Zhang, Xiaojin; Wang, Hongquan; Dai, Yu

    2018-05-01

    Click polymerization is a powerful polymerization technique for the construction of new macromolecules with well-defined structures and multifaceted functionalities. Here, we synthesize reduction-responsive polymeric prodrug PEG- b-(PSS- g-MTX)- b-PEG containing disulfide bonds and pendant methotrexate (MTX) via two-step click polymerization followed by conjugating MTX to pendant hydroxyl. MTX content in polymeric prodrug is 13.5%. Polymeric prodrug is able to form polymeric micelles by self-assembly in aqueous solution. Polymeric micelles are spherical nanoparticles with tens of nanometers in size. Of note, polymeric micelles are reduction-responsive due to disulfide bonds in the backbone of PEG- b-(PSS- g-MTX)- b-PEG and could release pendant drugs in the presence of the reducing agents such as dl-dithiothreitol (DTT).

  12. Use of Molecular Modeling to Determine the Interaction and Competition of Gases within Coal for Carbon Dioxide Sequestration

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jeffrey D. Evanseck; Jeffry D. Madura

    A 3-dimensional coal structural model for the Argonne Premium Coal Pocahontas No. 3 has been generated. The model was constructed based on the wealth of structural information available in the literature with the enhancement that the structural diversity within the structure was represented implicitly (for the first time) based on image analysis of HRTEM in combination with LDMS data. The complex and large structural model (>10,000 carbon atoms) will serve as a basis for examining the interaction of gases within this low volatile bituminous coal. Simulations are of interest to permit reasonable simulations of the host-guest interactions with regard tomore » carbon dioxide sequestration within coal and methane displacement from coal. The molecular structure will also prove useful in examining other coal related behavior such as solvent swelling, liquefaction and other properties. Molecular models of CO{sub 2} have been evaluated with water to analyze which classical molecular force-field parameters are the most reasonable to predict the interactions of CO{sub 2} with water. The comparison of the molecular force field models was for a single CO{sub 2}-H{sub 2}O complex and was compared against first principles quantum mechanical calculations. The interaction energies and the electrostatic interaction distances were used as criteria in the comparison. The ab initio calculations included Hartree-Fock, B3LYP, and Moeller-Plesset 2nd, 3rd, and 4th order perturbation theories with basis sets up to the aug-cc-pvtz basis set. The Steele model was the best literature model, when compared to the ab initio data, however, our new CO{sub 2} model reproduces the QM data significantly better than the Steele force-field model.« less

  13. Preliminary thermal-maturity map of the Cameo and Fairfield or equivalent coal zone in the Piceance Creek Basin, Colorado

    USGS Publications Warehouse

    Nuccio, Vito F.; Johnson, Ronald C.

    1983-01-01

    This map was prepared in cooperation with the U.S. Department of Energy's Western Gas Sands Project and was constructed to show the thermal maturity of the Upper Cretaceous Mesaverde Formation (or Group) in the Piceance Creek Basin. The ability of a source rock to generate oil and gas is directly related to its kerogen content and thermal maturity; hence, thermal maturity is commonly used as an exploration tool. This publication consists of two parts: a coal rank map for the basinwide Cameo and Fairfield or equivalent coal zone and three cross sections showing the variation in a coal rank for the entire Mesaverde. Structure contours on the map show the top of the Rollins Sandstone Member of the Mesaverde Formation and its equivalent the Trout Creek Sandstone Member of the Iles Formation of the Mesaverde Group, which immediately underlie the Cameo and Fairfield zone. The structure contours show the fairly strong correlation between structure and coal rank in the basin, suggesting that maximum overburden was the key factor in determining the coal ranks. Even in the southern part of the basin where extensive plutonism occurred during the Oligocene, coal ranks still generally follow structure; indicating that the plutons had little affect on the coals. On the cross sections both the top of the Rollins and Trout Creek, and the top of the Mesaverde Formation/Group are shown. A complete analysis of the entire Mesaverde in the basin would require more information than is presently available.

  14. Bio-inspired method to obtain multifunctional dynamic nanocomposites

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kushner, Aaron M.; Guan, Zhibin; Williams, Gregory

    A method for a polymeric or nanocomposite material. The method includes assembling a multiphase hard-soft structure, where the structure includes a hard micro- or nano-phase, and a soft micro- or nano-phase that includes a polymeric scaffold. In the method, the polymeric scaffold includes dynamically interacting motifs and has a glass transition temperature (T.sub.g) lower than the intended operating temperature of the material.

  15. Mechanical and thermal control of cleating and shearing in coal: examples from the Alabama coalbed methane field, USA

    USGS Publications Warehouse

    Pashin, Jack; Carroll, R.E.; Hatch, Joseph R.; Goldhaber, Martin B.

    1999-01-01

    Natural fractures provide most of the interconnected macroporosity in coal. Therefore, understanding the characteristics of these fractures and the associated mechanisms of formation is essential for effective coalbed methane exploration and field management. Natural fractures in coal can be divided into two general types: cleat and shear structures. Cleat has been studied for more than a century, yet the mechanisms of cleat formation remain poorly understood (see reviews by Close, 1993; Laubach et al.,1998). An important aspect of cleating is that systematic fracturing of coal is takes place in concert with devolatization and concomitant shrinkage of the coal matrix during thermal maturation (Ammosov and Eremin, 1960). Coal, furthermore, is a mechanically weak rock type that is subject to bedding-plane shear between more competent beds like shale, sandstone, and limestone. Yet, the significance of shear structures in coal has only begun to attract scientific interest (Hathaway and Gayer, 1996; Pashin, 1998).

  16. Macromolecular structural changes in bituminous coals during extraction and solubilization. Annual technical progress report, September 1, 1980-August 31, 1981

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Peppas, N.A.; Hill-Lievense, M.E.; Hooker, D.T. II

    1981-01-01

    Seven coal samples ranging from a lignite with 69.95% carbon to an anthracite with 94.17% carbon on a dry mineral matter-free (dmmf) basis were extracted with pyridine at its reflux temperature for two weeks. The coal matrices obtained were subjected to two degradation techniques, the Sternberg reductive alkylation technique and the Miyake alkylation technique. Gel permeation chromatographic analysis of pyridine-extracted liquids of the alkylated coal showed average molecular weights smaller than those of the original coal extracts. Electron impact mass spectrometry was used to obtain the mass spectra of these alkylated coal samples. Based on investigation of the recurring patternmore » of the peaks of the mass spectra of these products it was concluded that a cluster size of 126 to 130 is characteristic of the crosslinked structure of the coal studied. In addition, several chemical compounds in the range of m/e 78-191 were identified.« less

  17. Supramolecular "Step Polymerization" of Preassembled Micelles: A Study of "Polymerization" Kinetics.

    PubMed

    Yang, Chaoying; Ma, Xiaodong; Lin, Jiaping; Wang, Liquan; Lu, Yingqing; Zhang, Liangshun; Cai, Chunhua; Gao, Liang

    2018-03-01

    In nature, sophisticated functional materials are created through hierarchical self-assembly of nanoscale motifs, which has inspired the fabrication of man-made materials with complex architectures for a variety of applications. Herein, a kinetic study on the self-assembly of spindle-like micelles preassembled from polypeptide graft copolymers is reported. The addition of dimethylformamide and, subsequently, a selective solvent (water) can generate a "reactive point" at both ends of the spindles as a result of the existence of structural defects, which induces the "polymerization" of the spindles into nanowires. Experimental results combined with dissipative particle dynamics simulations show that the polymerization of the micellar subunits follows a step-growth polymerization mechanism with a second-order reaction characteristic. The assembly rate of the micelles is dependent on the subunit concentration and on the activity of the reactive points. The present work reveals a law governing the self-assembly kinetics of micelles with structural defects and opens the door for the construction of hierarchical structures with a controllable size through supramolecular step polymerization. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Photo-responsive polymeric micelles.

    PubMed

    Huang, Yu; Dong, Ruijiao; Zhu, Xinyuan; Yan, Deyue

    2014-09-07

    Photo-responsive polymeric micelles have received increasing attention in both academic and industrial fields due to their efficient photo-sensitive nature and unique nanostructure. In view of the photo-reaction mechanism, photo-responsive polymeric micelles can be divided into five major types: (1) photoisomerization polymeric micelles, (2) photo-induced rearrangement polymeric micelles, (3) photocleavage polymeric micelles, (4) photo-induced crosslinkable polymeric micelles, and (5) photo-induced energy conversion polymeric micelles. This review highlights the recent advances of photo-responsive polymeric micelles, including the design, synthesis and applications in various biomedical fields. Especially, the influence of different photo-reaction mechanisms on the morphology, structure and properties of the polymeric micelles is emphasized. Finally, the possible future directions and perspectives in this emerging area are briefly discussed.

  19. Structural Characterization of β-Agostic Bonds in Pd-Catalyzed Polymerization

    DOE PAGES

    Xu, Hongwei; Hu, Chunhua Tony; Wang, Xiaoping; ...

    2017-10-23

    β-agostic Pd complexes are critical intermediates in catalytic reactions, such as olefin polymerization and Heck reactions. Pd β-agostic complexes, however, have eluded structural characterization, due to the fact that these highly unstable molecules are difficult to isolate. In this paper, we report the single-crystal X-ray and neutron diffraction characterization of β-agostic (α-diimine)Pd–ethyl intermediates in polymerization. Short C α–C β distances and acute Pd–C α–C β bond angles combined serve as unambiguous evidence for the β-agostic interaction. Finally, characterization of the agostic structure and the kinetic barrier for β-H elimination offer important insight into the fundamental understanding of agostic bonds andmore » the mechanism of polymerization.« less

  20. Structural Characterization of β-Agostic Bonds in Pd-Catalyzed Polymerization

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Xu, Hongwei; Hu, Chunhua Tony; Wang, Xiaoping

    β-agostic Pd complexes are critical intermediates in catalytic reactions, such as olefin polymerization and Heck reactions. Pd β-agostic complexes, however, have eluded structural characterization, due to the fact that these highly unstable molecules are difficult to isolate. In this paper, we report the single-crystal X-ray and neutron diffraction characterization of β-agostic (α-diimine)Pd–ethyl intermediates in polymerization. Short C α–C β distances and acute Pd–C α–C β bond angles combined serve as unambiguous evidence for the β-agostic interaction. Finally, characterization of the agostic structure and the kinetic barrier for β-H elimination offer important insight into the fundamental understanding of agostic bonds andmore » the mechanism of polymerization.« less

  1. Role of oxygen functional groups for structure and dynamics of interfacial water on low rank coal surface: a molecular dynamics simulation

    NASA Astrophysics Data System (ADS)

    You, Xiaofang; Wei, Hengbin; Zhu, Xianchang; Lyu, Xianjun; Li, Lin

    2018-07-01

    Molecular dynamics simulations were employed to study the effects of oxygen functional groups for structure and dynamics properties of interfacial water molecules on the subbituminous coal surface. Because of complex composition and structure, the graphite surface modified by hydroxyl, carboxyl and carbonyl groups was used to represent the surface model of subbituminous coal according to XPS results, and the composing proportion for hydroxyl, carbonyl and carboxyl is 25:3:5. The hydration energy with -386.28 kJ/mol means that the adsorption process between water and coal surface is spontaneous. Density profiles for oxygen atoms and hydrogen atoms indicate that the coal surface properties affect the structural and dynamic characteristics of the interfacial water molecules. The interfacial water exhibits much more ordering than bulk water. The results of radial distribution functions, mean square displacement and local self-diffusion coefficient for water molecule related to three oxygen moieties confirmed that the water molecules prefer to absorb with carboxylic groups, and adsorption of water molecules at the hydroxyl and carbonyl is similar.

  2. Polymeric Janus Nanoparticles: Recent Advances in Synthetic Strategies, Materials Properties, and Applications.

    PubMed

    Fan, Xiaoshan; Yang, Jing; Loh, Xian Jun; Li, Zibiao

    2018-06-13

    Polymeric Janus nanoparticles with two sides of incompatible chemistry have received increasing attention due to their tunable asymmetric structure and unique material characteristics. Recently, with the rapid progress in controlled polymerization combined with novel fabrication techniques, a large array of functional polymeric Janus particles are diversified with sophisticated architecture and applications. In this review, the most recently developed strategies for controlled synthesis of polymeric Janus nanoparticles with well-defined size and complex superstructures are summarized. In addition, the pros and cons of each approach in mediating the anisotropic shapes of polymeric Janus particles as well as their asymmetric spatial distribution of chemical compositions and functionalities are discussed and compared. Finally, these newly developed structural nanoparticles with specific shapes and surface functions orientated applications in different domains are also discussed, followed by the perspectives and challenges faced in the further advancement of polymeric Janus nanoparticles as high performance materials. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Recent advances of basic materials to obtain electrospun polymeric nanofibers for medical applications

    NASA Astrophysics Data System (ADS)

    Manea, L. R.; Hristian, L.; Leon, A. L.; Popa, A.

    2016-08-01

    The most important applications of electrospun polymeric nanofibers are by far those from biomedical field. From the biological point of view, almost all the human tissues and organs consist of nanofibroas structures. The examples include the bone, dentine, cartilage, tendons and skin. All these are characterized through different fibrous structures, hierarchically organized at nanometer scale. Electrospinning represents one of the nanotechnologies that permit to obtain such structures for cell cultures, besides other technologies, such as selfassembling and phase separation technologies. The basic materials used to produce electrospun nanofibers can be natural or synthetic, having polymeric, ceramic or composite nature. These materials are selected depending of the nature and structure of the tissue meant to be regenerated, namely: for the regeneration of smooth tissues regeneration one needs to process through electrospinning polymeric basic materials, while in order to obtain the supports for the regeneration of hard tissues one must mainly use ceramic materials or composite structures that permit imbedding the bioactive substances in distinctive zones of the matrix. This work presents recent studies concerning basic materials used to obtain electrospun polymeric nanofibers, and real possibilities to produce and implement these nanofibers in medical bioengineering applications.

  4. Direct evidence for the gas phase thermal polymerization of styrene. Determination of the initiation mechanism and structures of the early oligomers by ion mobility.

    PubMed

    Alsharaeh, Edreese H; Ibrahim, Yehia M; El-Shall, M Samy

    2005-05-04

    We present here direct evidence for the thermal self-initiated polymerization of styrene in the gas phase and establish that the initiation process proceeds via essentially the same mechanism (the Mayo mechanism) as in condensed phase polymerization. Furthermore, we provide structural identifications of the dimers and trimers formed in the gas phase.

  5. Two-photon polymerization of a three dimensional structure using beams with orbital angular momentum

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zhang, Shi-Jie; Li, Yan, E-mail: li@pku.edu.cn; Liu, Zhao-Pei

    The focus of a beam with orbital angular momentum exhibits internal structure instead of an elliptical intensity distribution of a Gaussian beam, and the superposition of Gauss-Laguerre beams realized by two-dimensional phase modulation can generate a complex three-dimensional (3D) focus. By taking advantage of the flexibility of this 3D focus tailoring, we have fabricated a 3D microstructure with high resolution by two-photon polymerization with a single exposure. Furthermore, we have polymerized an array of double-helix structures that demonstrates optical chirality.

  6. Tubulin polymerization-stimulating activity of Ganoderma triterpenoids.

    PubMed

    Kohno, Toshitaka; Hai-Bang, Tran; Zhu, Qinchang; Amen, Yhiya; Sakamoto, Seiichi; Tanaka, Hiroyuki; Morimoto, Satoshi; Shimizu, Kuniyoshi

    2017-04-01

    Tubulin polymerization is an important target for anticancer therapies. Even though the potential of Ganoderma triterpenoids against various cancer targets had been well documented, studies on their tubulin polymerization-stimulating activity are scarce. This study was conducted to evaluate the effect of Ganoderma triterpenoids on tubulin polymerization. A total of twenty-four compounds were investigated using an in vitro tubulin polymerization assay. Results showed that most of the studied triterpenoids exhibited microtuble-stabilizing activity to different degrees. Among the investigated compounds, ganoderic acid T-Q, ganoderiol F, ganoderic acid S, ganodermanontriol and ganoderic acid TR were found to have the highest activities. A structure-activity relationship (SAR) analysis was performed. Extensive investigation of the SAR suggests the favorable structural features for the tubulin polymerization-stimulating activity of lanostane triterpenes. These findings would be helpful for further studies on the potential mechanisms of the anticancer activity of Ganoderma triterpenoids and give some indications on the design of tubulin-targeting anticancer agents.

  7. Structural characterization/correlation of calorimetric properties of coal fluids: Final report, September 1, 1985--August 31, 1988

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Starling, K.E.; Mallinson, R.G.; Li, M.H.

    The objective of this research is to examine the relationship between the calorimetric properties of coal fluids and their molecular functional group composition. Coal fluid samples which have had their calorimetric properties measured are characterized using proton NMR, IR, and elemental analysis. These characterizations are then used in a chemical structural model to determine the composition of the coal fluid in terms of the important molecular functional groups. These functional groups are particularly important in determining the intramolecular based properties of a fluid, such as ideal gas heat capacities. Correlational frameworks for ideal gas heat capacities are then examined withinmore » an existing equation of state methodology to determine an optimal correlation. The optimal correlation for obtaining the characterization/chemical structure information and the sensitivity of the correlation to the characterization and structural model is examined. 8 refs.« less

  8. Structural characterization/correlation of calorimetric properties of coal fluids: Second annual report, September 1, 1986-August 31, 1987

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Starling, K.E.; Mallinson, R.G.; Li, M.H.

    The objective of this research is to examine the relationship between the calorimetric properties of coal fluids and their molecular functional group composition. Coal fluid samples which have had their calorimetric properties measured are characterized using proton NMR, ir, and elemental analysis. These characterizations are then used in a chemical structural model to determine the composition of the coal fluid in terms of the important molecular functional groups. These functional groups are particularly important in determining the intramolecular based properties of a fluid, such as ideal gas heat capacities. Correlational frameworks for ideal gas heat capacities are then examined withinmore » an existing equation of state methodology to determine an optimal correlation. The optimal correlation for obtaining the characterization/chemical structure information and the sensitivity of the correlation to the characterization and structural model is examined.« less

  9. Structural characterization/correlation of calorimetric properties of coal fluids. First annual report, September 1, 1985-August 31, 1986

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Starling, K.E.; Mallinson, R.G.; Li, M.H.

    The objective of this research is to examine the relationship between the calorimetric properties of coal liquids and their molecular functional group composition. Coal liquid samples which have had their calorimetric properties measured are characterized using proton NMR, ir and elemental analysis. These characterizations are then used in a chemical structural model to determine the composition of the coal liquid in terms of the important molecular functional groups. These functional groups are particularly important in determining the intramolecular based properties of a fluid, such as ideal gas heat capacities. Correlational frameworks for heat capacities will then be examined within anmore » existing equation of state methodology to determine an optimal correlation. Also, the optimal recipe for obtaining the characterization/chemical structure information and the sensitivity of the correlation to the characterization and structural model will be examined and determined. 7 refs.« less

  10. DNA-Templated Polymerization of Side-Chain-Functionalized Peptide Nucleic Acid Aldehydes

    PubMed Central

    Kleiner, Ralph E.; Brudno, Yevgeny; Birnbaum, Michael E.; Liu, David R.

    2009-01-01

    The DNA-templated polymerization of synthetic building blocks provides a potential route to the laboratory evolution of sequence-defined polymers with structures and properties not necessarily limited to those of natural biopolymers. We previously reported the efficient and sequence-specific DNA-templated polymerization of peptide nucleic acid (PNA) aldehydes. Here, we report the enzyme-free, DNA-templated polymerization of side-chain-functionalized PNA tetramer and pentamer aldehydes. We observed that the polymerization of tetramer and pentamer PNA building blocks with a single lysine-based side chain at various positions in the building block could proceed efficiently and sequence-specifically. In addition, DNA-templated polymerization also proceeded efficiently and in a sequence-specific manner with pentamer PNA aldehydes containing two or three lysine side chains in a single building block to generate more densely functionalized polymers. To further our understanding of side-chain compatibility and expand the capabilities of this system, we also examined the polymerization efficiencies of 20 pentamer building blocks each containing one of five different side-chain groups and four different side-chain regio- and stereochemistries. Polymerization reactions were efficient for all five different side-chain groups and for three of the four combinations of side-chain regio- and stereochemistries. Differences in the efficiency and initial rate of polymerization correlate with the apparent melting temperature of each building block, which is dependent on side-chain regio- and stereochemistry, but relatively insensitive to side-chain structure among the substrates tested. Our findings represent a significant step towards the evolution of sequence-defined synthetic polymers and also demonstrate that enzyme-free nucleic acid-templated polymerization can occur efficiently using substrates with a wide range of side-chain structures, functionalization positions within each building block, and functionalization densities. PMID:18341334

  11. Mapping Polymerization and Allostery of Hemoglobin S Using Point Mutations

    PubMed Central

    Weinkam, Patrick; Sali, Andrej

    2014-01-01

    Hemoglobin is a complex system that undergoes conformational changes in response to oxygen, allosteric effectors, mutations, and environmental changes. Here, we study allostery and polymerization of hemoglobin and its variants by application of two previously described methods: (i) AllosMod for simulating allostery dynamics given two allosterically related input structures and (ii) a machine-learning method for dynamics- and structure-based prediction of the mutation impact on allostery (Weinkam et al. J. Mol. Biol. 2013), now applicable to systems with multiple coupled binding sites such as hemoglobin. First, we predict the relative stabilities of substates and microstates of hemoglobin, which are determined primarily by entropy within our model. Next, we predict the impact of 866 annotated mutations on hemoglobin’s oxygen binding equilibrium. We then discuss a subset of 30 mutations that occur in the presence of the sickle cell mutation and whose effects on polymerization have been measured. Seven of these HbS mutations occur in three predicted druggable binding pockets that might be exploited to directly inhibit polymerization; one of these binding pockets is not apparent in the crystal structure but only in structures generated by AllosMod. For the 30 mutations, we predict that mutation-induced conformational changes within a single tetramer tend not to significantly impact polymerization; instead, these mutations more likely impact polymerization by directly perturbing a polymerization interface. Finally, our analysis of allostery allows us to hypothesize why hemoglobin evolved to have multiple subunits and a persistent low frequency sickle cell mutation. PMID:23957820

  12. Spin-mapping of Coal Structures with ESE and ENDOR

    DOE R&D Accomplishments Database

    Belford, R. L.; Clarkson, R. B.

    1989-12-01

    The broad goals of this project are to determine by nondestructive magnetic resonance methods chemical and physical structural characteristics of organic parts of native and treated coals. In this project period, we have begun to explore a technique which promises to enable us to follow to course of coal cleaning processes with microscopic spatial resolution. For the past five years, our laboratory has worked on extensions of the EPR technique as applied to coal to address these analytical problems. In this report we (1) describe the world's first nuclear magnetic resonance imaging results from an Illinois {number sign}6 coal and (2) transmit a manuscript describing how organic sulfur affect the very-high-frequency EPR spectra of coals. Magnetic resonance imaging (MRI) is a non-destructive technique that has found wide medical application as a means of visualizing the interior of human bodies. We have used MRI techniques to study the diffusion of an organic solvent (DMSO) into the pores of Illinois {number sign}6 coal. Proton MRI images reveal that this solvent at room temperature does not penetrate approximately 30% of the coal volume. Regions of the coal that exclude solvent could be related to inertinite and mineral components. A multi-technique imaging program is contemplated.

  13. Effects of HMW-GS Ax1 or Dx2 absence on the glutenin polymerization and gluten micro structure of wheat (Triticum aestivum L.).

    PubMed

    Gao, Xin; Liu, Tianhong; Ding, Mengyun; Wang, Jun; Li, Chunlian; Wang, Zhonghua; Li, Xuejun

    2018-02-01

    Wheat (Triticum aestivum L.) dough strength and extensibility are mainly determined by the polymerization of glutenin. The number of high-molecular-weight glutenin subunits (HMW-GS) differs in various wheat varieties due to the silencing of some genes. The effects of Ax1 or Dx2 subunit absence on glutenin polymerization, dough mixing properties and gluten micro structure were investigated with two groups of near-isogenic lines. The results showed that Ax1 or Dx2 absence decreased the accumulation rate of glutenin polymers and thus delayed the rapid increase period for glutenin polymerization by at least ten days, which led to lower percentage of polymeric protein in mature grain. Ax1 or Dx2 absence significantly decreased the dough development time and dough stability, but increased the uniformity of micro structure. Lacunarity, derived from quantitative analysis of gluten network, is suggested as a new indicator for wheat quality. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. All-Water-Jet Coal Excavator

    NASA Technical Reports Server (NTRS)

    Gangal, M. D.

    1985-01-01

    Version of jaw miner operates without mechanical cutting and crushing. Forward-pointing jets of water dislodge and break up coal. Rearward-pointing jets further break up coal and force particles into slurry chamber. Oscillatingjet mechanism itself stays within "jaw" structure and protected from wear and tear associated with coal handling. All-jet machine generates even less dust than anger, therefore poses lesser explosion or health hazard.

  15. 76 FR 53483 - Notice of Invitation To Participate; Coal Exploration License Application NMNM 126245, New Mexico

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-26

    ..., as amended by the Federal Coal Leasing Amendments Act of 1976, and to Bureau of Land Management (BLM... program is to gain structural and quality information about the coal. The BLM regulations at 43 CFR 3410 require the publication of an invitation to participate in the coal exploration in the Federal Register...

  16. The methods of receiving coal water suspension and its use as the modifying additive in concrete

    NASA Astrophysics Data System (ADS)

    Buyantuyev, S. L.; Urkhanova, L. A.; Lkhasaranov, S. A.; Stebenkova, Y. Y.; Khmelev, A. B.; Kondratenko, A. S.

    2017-01-01

    Results of research of the coal water suspension (CWS) from a cake received in the electrodigit ways in the fluid environment and gas are given in article and also the possibilities of its use as the modifying additive in concrete are considered. Use of a coal cake is perspective as it is a withdrawal of the coal and concentrating enterprises and has extremely low cost. Methods of receiving CWS and possibility of formation of carbon nanomaterials (CNM) are given in their structure. Research and the analysis of a microstructure of a surface of exemplars before electrodigit processing, their element structure, dependence of durability of a cement stone on a look and quantity of an additive of CWS is conducted. For modification of cement the carbon nanomaterials received from the following exemplars of water coal suspensions were used: foams from a cake from a scrubber of the plasma modular reactor, coal water suspension from a cake from electrodigit installation. The product which can find further application for a power engineering as fuel for combustion, and also in structural materials science, in particular, as the modifying additive in concrete allows to receive these methods.

  17. Coal mining activities change plant community structure due to air pollution and soil degradation.

    PubMed

    Pandey, Bhanu; Agrawal, Madhoolika; Singh, Siddharth

    2014-10-01

    The aim of this study was to investigate the effects of coal mining activities on the community structures of woody and herbaceous plants. The response of individual plants of community to defilement caused by coal mining was also assessed. Air monitoring, soil physico-chemical and phytosociological analyses were carried around Jharia coalfield (JCF) and Raniganj coalfield. The importance value index of sensitive species minified and those of tolerant species enhanced with increasing pollution load and altered soil quality around coal mining areas. Although the species richness of woody and herbaceous plants decreased with higher pollution load, a large number of species acclimatized to the stress caused by the coal mining activities. Woody plant community at JCF was more affected by coal mining than herbaceous community. Canonical correspondence analysis revealed that structure of herbaceous community was mainly driven by soil total organic carbon, soil nitrogen, whereas woody layer community was influenced by sulphur dioxide in ambient air, soil sulphate and soil phosphorus. The changes in species diversity observed at mining areas indicated an increase in the proportion of resistant herbs and grasses showing a tendency towards a definite selection strategy of ecosystem in response to air pollution and altered soil characteristics.

  18. Relationship between Maceral of Coal and Coal-bed Methane adsorption ability in Sihe Coalmine of Qinshui Basin, China

    NASA Astrophysics Data System (ADS)

    Wang, M. S.; Zou, G. G.; Zhu, R. B.

    2018-05-01

    Maceral components and its content of coal were divided based on the microscopic characteristics of coal. The Langmuir volume and the Langmuir pressure were tested, and the Langmuir volume represents the adsorption capacity of coal. The formation of coal bed methane is affected by the partition of the maceral components in coal. Therefore, the relationship between maceral composition and coal bed methane adsorption capacity of coal was analyzed. The results show that the maceral components of coal are dominated by vitrinite and inertinite in the study area, and the content of inertinite is below 32%. The vitrinite group has a negative linear correlation with the Langmuir volume, and the inertia composition has a positive linear correlation with it. The cellular structures in the inertinite are the main site of coal bed methane enrichment. The microstructure of coal affects the coalbed methane content and the stage of hydrocarbon generation in coal. This indicates that the microstructure of coal is one of the important factors influencing the adsorption capacity of coal seam.

  19. TRANSITION METAL CATALYSIS IN CONTROLLED RADICAL POLYMERIZATION: ATOM TRANSFER RADICAL POLYMERIZATION. (R826735)

    EPA Science Inventory

    Novel and diversified macromolecular structures, which include polymers with designed topologies (top), compostions (middle), and functionalities (bottom), can be prepared by atom transfer radical polymerization processes. These polymers can be synthesized from a large variety of...

  20. Interaction and the structures of coal

    NASA Astrophysics Data System (ADS)

    Opaprakasit, Pakorn

    The origin of a decrease in the amount of soluble material from coal upon a reflux treatment has been investigated in an attempt to obtain insight into the nature of the interaction in the macromolecular network structure of coal. This decrease in the extractable material is a result of an increase in the amount of physical cross-links associated with secondary interactions. The alternate possibility of covalent cross-link formation by ether linkage was found to be unlikely because the coal hydroxyl content remains unchanged upon heat treatment. The functional groups responsible for forming these physical cross-links and their contents vary from coal to coal with coal rank. Carboxylate/cation complexes, similar to those found in ionomers, dominate in low rank coal. In high rank coal, the clusters involving pi-cation interactions were observed. Both mechanisms seem to play a role in mid rank coals. These physical cross-links are responsible for a lowering of the extraction yield of coal, but are disrupted by a treatment with acid solution, resulting in an increase in the extraction yield. As a consequence, the cross-links in coal structure should be classified into two types; a "permanent" covalent cross-link, which break under extreme conditions such as chemical reaction and pyrolysis, and "reversible" cross-links, largely associated with ionomer-like structure and pi-cation interactions. The interaction between a "magic" solvent of N-methylpyrollidone and carbon disulfide (NMP/CS2) and its role in the unusual extractability enhancement of Upper Freeport coal has also been investigated. The results strongly suggest that NMP/CS2 mixed solvents form complexes with cations. These mixed solvents are capable of forming a solid complex with cations from NaOH and some simple salts, such as NaCl and LiCl. Given that Upper Freeport coal contains a large amount of mineral matter, it is not surprising that these types of complexes could be formed in the present of the mixed solvents, which in turn enhances the coal extraction yield. Finally, the evidence for the presence of a glass transition temperature in coal was examined. The results from Differential Scanning Calorimetry showed that no transition similar to the Tg can be observed in bulk coal or its low-molecular weight fraction, pyridine soluble extracted material, at a temperature near 110°C. In contrast, an irreversible transition that is due to water evaporation has been found. Thermomechanical measurements, which are very sensitive to the presence of a Tg in synthetic polymers, also provided no evidence for a Tg below temperatures where chemical reactions occur. Additionally, the results from Thermomechanical Analysis showed an expansion in size when the coal was heated to 300°C, which is associated with a "caking" process. The degree of expansion during this "caking" process is about five times greater in the direction perpendicular to the bedding plane than the parallel, indicating an accommodation of anisotropic strain relaxation, which was generated in the direction perpendicular to the bedding plane during the coalification process.

  1. New method to access hyperbranched polymers with uniform structure via one-pot polymerization of inimer in microemulsion.

    PubMed

    Min, Ke; Gao, Haifeng

    2012-09-26

    A facile approach is presented for successful synthesis of hyperbranched polymers with high molecular weight and uniform structure by a one-pot polymerization of an inimer in a microemulsion. The segregated space in the microemulsion confined the inimer polymerization and particularly the polymer-polymer reaction within discrete nanoparticles. At the end of polymerization, each nanoparticle contained one hyperbranched polymer that had thousands of inimer units and low polydispersity. The hyperbranched polymers were used as multifunctional macroinitiators for synthesis of "hyper-star" polymers. When a degradable inimer was applied, the hyper-stars showed fast degradation into linear polymer chains with low molecular weight.

  2. Changes in pore structure of coal caused by coal-to-gas bioconversion

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zhang, Rui; Liu, Shimin; Bahadur, Jitendra

    Microbial enhanced coalbed methane (ME-CBM) recovery is critically examined as a viable technology for natural gas recovery from coalbed methane (CBM) reservoirs. Since the majority of gas-in-place (GIP) is stored as an adsorbed phase in fine pores of coal matrix, the nano-pore structure directly influences gas storage and transport properties. Only limited studies have quantified the alteration of the nano-pore structure due to ME-CBM treatment. This study examines the evolution of the pore structure using a combination of small angle X-ray scattering (SAXS), low-pressure N 2 and CO 2 adsorption (LPGA) and high-pressure methane adsorption methods. The results show thatmore » the surface fractal dimension decreases for the two bioconverted coals compared to the untreated coal. After bio-treatment, the mesopore surface area and pore volume decrease with the average pore diameter increases, while the micropore surface area increases with pore volume decreases. Both inaccessible meso-/micropore size distributions decrease after bioconversion, while the accessible micropore size distribution increases, making a portion of closed micropore network accessible. In addition, the methane adsorption capacities increase after bio-treatment, which is confirmed by the increase of micropore surface area. A conceptual physical model of methanogenesis is proposed based on the evolution of the pore structure.« less

  3. Changes in pore structure of coal caused by coal-to-gas bioconversion

    DOE PAGES

    Zhang, Rui; Liu, Shimin; Bahadur, Jitendra; ...

    2017-06-19

    Microbial enhanced coalbed methane (ME-CBM) recovery is critically examined as a viable technology for natural gas recovery from coalbed methane (CBM) reservoirs. Since the majority of gas-in-place (GIP) is stored as an adsorbed phase in fine pores of coal matrix, the nano-pore structure directly influences gas storage and transport properties. Only limited studies have quantified the alteration of the nano-pore structure due to ME-CBM treatment. This study examines the evolution of the pore structure using a combination of small angle X-ray scattering (SAXS), low-pressure N 2 and CO 2 adsorption (LPGA) and high-pressure methane adsorption methods. The results show thatmore » the surface fractal dimension decreases for the two bioconverted coals compared to the untreated coal. After bio-treatment, the mesopore surface area and pore volume decrease with the average pore diameter increases, while the micropore surface area increases with pore volume decreases. Both inaccessible meso-/micropore size distributions decrease after bioconversion, while the accessible micropore size distribution increases, making a portion of closed micropore network accessible. In addition, the methane adsorption capacities increase after bio-treatment, which is confirmed by the increase of micropore surface area. A conceptual physical model of methanogenesis is proposed based on the evolution of the pore structure.« less

  4. Studies of coupled chemical and catalytic coal conversion methods

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Stock, L.M.

    1988-01-01

    Liquefaction of coal by depolymerization in an organic solvent has been studied for several years. The liquefied coal extract which results from such a process is far more suitable for conversion into liquid fuel by hydrogenolysis than is the untreated coal. Investigations on the chemical structure and the reactive sites of coal can help to select useful reactions for the production of liquids from coal. Sternberg et al. demonstrated that the reductive alkylation method transforms bituminous coal into an enormously soluble substance, irrespective of the mild reaction conditions. The effectiveness of newly introduced alkyl groups for the disruption of intermolecularmore » hydrogen bonds and pi-pi interactions between the aromatic sheets in coal macromolecules has been recognized. It has been reported by Ignasiak et al. that a C-alkylabon reaction using sodium or potassium amide in liquid ammonia can be used to introduce alkyl groups at acidic carbon sites. A method has been developed recently in this laboratory for the solubilization of high rank coals. In the previous reports it was shown that n-butyl lithium and potassium t-butoxide in refluxing heptane produced coal anions which could be alkylated with different alkyl halides. Such alkylated coals were soluble up to 92% in solvents like pyridine. Though the solubilization of coal depended very much on the length of the alkyl group, it also depended very much on the nature of the base used. Strong bases like n-butyl lithium (pKa=42) can cause proton abstraction from aromatic structures, if the more acidic benzylic protons are absent. The utility of this procedure, initially developed and used by Miyake and Stock, has now been tested with the high oxygen containing, low rank Illinois No. 6 and Wyodak coals.« less

  5. Studies of coupled chemical and catalytic coal conversion methods. Fifth quarterly report, October--December 1988

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Stock, L.M.

    1988-12-31

    Liquefaction of coal by depolymerization in an organic solvent has been studied for several years. The liquefied coal extract which results from such a process is far more suitable for conversion into liquid fuel by hydrogenolysis than is the untreated coal. Investigations on the chemical structure and the reactive sites of coal can help to select useful reactions for the production of liquids from coal. Sternberg et al. demonstrated that the reductive alkylation method transforms bituminous coal into an enormously soluble substance, irrespective of the mild reaction conditions. The effectiveness of newly introduced alkyl groups for the disruption of intermolecularmore » hydrogen bonds and pi-pi interactions between the aromatic sheets in coal macromolecules has been recognized. It has been reported by Ignasiak et al. that a C-alkylabon reaction using sodium or potassium amide in liquid ammonia can be used to introduce alkyl groups at acidic carbon sites. A method has been developed recently in this laboratory for the solubilization of high rank coals. In the previous reports it was shown that n-butyl lithium and potassium t-butoxide in refluxing heptane produced coal anions which could be alkylated with different alkyl halides. Such alkylated coals were soluble up to 92% in solvents like pyridine. Though the solubilization of coal depended very much on the length of the alkyl group, it also depended very much on the nature of the base used. Strong bases like n-butyl lithium (pKa=42) can cause proton abstraction from aromatic structures, if the more acidic benzylic protons are absent. The utility of this procedure, initially developed and used by Miyake and Stock, has now been tested with the high oxygen containing, low rank Illinois No. 6 and Wyodak coals.« less

  6. Research on a new type of additive for CWS from low temperature pyrolysis tar

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wu Guoguang; Wang Zuna

    1997-12-31

    In this paper, coal tar from flash pyrolysis of Ping Zhuang lignite with solid heat carrier was used as raw material, which was directly synthesized a new type of additive for coal water slurry (CWS) in the laboratory. The wetting heat between the lignite and distilled water and solution of additive has been determined. It is evident that the wetting heat between the lignite and distilled water is very high, up to 44.56 J/g, which is harmful to preparing CWS. The wetting heat between the lignite and a solution of additive is reduced, which is related to its characteristics suchmore » as surface properties, oxygen functional groups and structure. The effect of coal properties on preparing CWS has also been analyzed systematically. It is suggested that the concentration of CWS is regularly changed with oxygen content of coal based on moisture and ash content. It is emphasized that when the influence of macerals on slurriability of coal is observed, inherent properties of each maceral such as pore structure, porosity, oxygen functional groups, grindability must be tightly combined to evaluate comprehensively. The structural characteristics of the additive matches well the molecular structure and surface properties of the coal. It is seen by synthetic experiments that suitable a degree of sulphonating and condensation are beneficial to preparing CWS. The rheology and stability of CWS have also been investigated. The result indicates that the stability of CWS using the new type of additive is improved, and the production cost of the additive synthesized from low temperature pyrolysis coal tar can be reduced.« less

  7. Formation and retention of methane in coal

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hucka, V.J.; Bodily, D.M.; Huang, H.

    1992-05-15

    The formation and retention of methane in coalbeds was studied for ten Utah coal samples, one Colorado coal sample and eight coal samples from the Argonne Premium Coal Sample Bank.Methane gas content of the Utah and Colorado coals varied from zero to 9 cm{sup 3}/g. The Utah coals were all high volatile bituminous coals. The Colorado coal was a gassy medium volatile bituminous coal. The Argonne coals cover a range or rank from lignite to low volatile bituminous coal and were used to determine the effect of rank in laboratory studies. The methane content of six selected Utah coal seamsmore » and the Colorado coal seam was measured in situ using a special sample collection device and a bubble desorbometer. Coal samples were collected at each measurement site for laboratory analysis. The cleat and joint system was evaluated for the coal and surrounding rocks and geological conditions were noted. Permeability measurements were performed on selected samples and all samples were analyzed for proximate and ultimate analysis, petrographic analysis, {sup 13}C NMR dipolar-dephasing spectroscopy, and density analysis. The observed methane adsorption behavior was correlated with the chemical structure and physical properties of the coals.« less

  8. Formation and retention of methane in coal. Final report

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hucka, V.J.; Bodily, D.M.; Huang, H.

    1992-05-15

    The formation and retention of methane in coalbeds was studied for ten Utah coal samples, one Colorado coal sample and eight coal samples from the Argonne Premium Coal Sample Bank.Methane gas content of the Utah and Colorado coals varied from zero to 9 cm{sup 3}/g. The Utah coals were all high volatile bituminous coals. The Colorado coal was a gassy medium volatile bituminous coal. The Argonne coals cover a range or rank from lignite to low volatile bituminous coal and were used to determine the effect of rank in laboratory studies. The methane content of six selected Utah coal seamsmore » and the Colorado coal seam was measured in situ using a special sample collection device and a bubble desorbometer. Coal samples were collected at each measurement site for laboratory analysis. The cleat and joint system was evaluated for the coal and surrounding rocks and geological conditions were noted. Permeability measurements were performed on selected samples and all samples were analyzed for proximate and ultimate analysis, petrographic analysis, {sup 13}C NMR dipolar-dephasing spectroscopy, and density analysis. The observed methane adsorption behavior was correlated with the chemical structure and physical properties of the coals.« less

  9. Economic and Technological Role of Kuzbass Industry in the Implementation of National Energy Strategy of Russian Federation

    NASA Astrophysics Data System (ADS)

    Zhironkin, S. A.; Khoreshok, A. A.; Tyulenev, M. A.; Barysheva, G. A.; Hellmer, M. C.

    2016-08-01

    This article describes the problems and prospects of development of coal mining in Kuzbass - the center of coal production in Siberia and Russia, in the framework of the major initiatives of the National Energy Strategy for the period until 2035. The structural character of the regional coal industry problems, caused by decline in investment activity, high level of fixed assets depreciation, slow development of deep coal processing and technological reduction of coal mining is shown.

  10. Potentiometric-surface map of the Wyodak-Anderson Coal Bed, Powder River Structural Basin, Wyoming, 1973-84

    USGS Publications Warehouse

    Daddow, Pamela B.

    1986-01-01

    Previous water level maps of shallow aquifers in the Powder River structural basin in Wyoming were based on water levels from wells completed in different stratigraphic intervals within thick sequences of sedimentary rocks. A potentiometric surface using water levels from a single aquifer had never been mapped throughout the basin. The sandstone aquifers in the Fort Union Formation of Paleocene age and the Wasatch Formation of Eocene age are discontinuous and lenticular, and do not extend even short distances. Coal aquifers are more continuous and the Wyodak-Anderson coal bed, in the Fort Union Formation, has been mapped in much of the Powder River structural basin in Wyoming. Water level altitudes in the Wyodak-Anderson coal bed and other stratigraphically equivalent coal beds were mapped to determine if they represent a continuous potentiometric surface in the Powder River structural basin. The potentiometric surface, except in the vicinity of the Wyodak mine east of Gillette, represents a premining condition as it was based on water level measurements made during 1973-84 that were not significantly affected by mining. The map was prepared in cooperation with the U.S. Bureau of Land Management. (Lantz-PTT)

  11. Raman spectral characteristics of magmatic-contact metamorphic coals from Huainan Coalfield, China

    NASA Astrophysics Data System (ADS)

    Chen, Shancheng; Wu, Dun; Liu, Guijian; Sun, Ruoyu

    2017-01-01

    Normal burial metamorphism of coal superimposed by magmatic-contact metamorphism makes the characteristics of the Raman spectrum of coal changed. Nine coal samples were chosen at a coal transect perpendicular to the intrusive dike, at the No. 3 coal seam, Zhuji Coal Mine, Huainan Coalfield, China, with different distances from dike-coal boundary (DCB). Geochemical (proximate and ultimate) analysis and mean random vitrinite reflectance (R0, %) indicate that there is a significant relationship between the values of volatile matter and R0 in metamorphosed coals. Raman spectra show that the graphite band (G band) becomes the major band but the disordered band (D band) disappears progressively, with the increase of metamorphic temperature in coals, showing that the structural organization in high-rank contact-metamorphosed coals is close to that of well-crystallized graphite. Evident relationships are observed between the calculated Raman spectral parameters and the peak metamorphic temperature, suggesting some spectral parameters have the potentials to be used as geothermometers for contact-metamorphic coals.

  12. Applications of acoustics in the measurement of coal slab thickness

    NASA Technical Reports Server (NTRS)

    Hadden, W. J., Jr.; Mills, J. M.; Pierce, A. D.

    1980-01-01

    The determination of the possibility of employing acoustic waves at ultrasonic frequencies for measurements of thicknesses of slabs of coal backed by shale is investigated. Fundamental information concerning the acoustical properties of coal, and the relationship between these properties and the structural and compositional parameters used to characterize coal samples was also sought. The testing device, which utilizes two matched transducers, is described.

  13. Research regarding biodegradable properties of food polymeric products under microorganism activity

    NASA Astrophysics Data System (ADS)

    Opran, Constantin; Lazar, Veronica; Fierascu, Radu Claudiu; Ditu, Lia Mara

    2018-02-01

    Aim of this research is the structural analysis by comparison of the biodegradable properties of two polymeric products made by non-biodegradable polymeric material (polypropylene TIPPLEN H949 A) and biodegradable polymeric material (ECOVIO IS 1335), under microorganism activity in order to give the best solution for the manufacture of food packaging biodegradable products. It presents the results of experimental determinations on comparative analysis of tensile strength for the two types of polymers. The sample weight variations after fungal biodegradation activity revealed that, after 3 months, there are no significant changes in polymeric substratum for non-biodegradable polymeric. The microscopically analysis showed that the fungal filaments did not strongly adhered on the non-biodegradable polymeric material, instead, both filamentous fungi strains adhered and covered the surface of the biodegradable sample with germinated filamentous conidia. The spectral analysis of polymer composition revealed that non-biodegradable polymer polypropylene spectra are identical for control and for samples that were exposed to fungal activity, suggesting that this type of sample was not degraded by the fungi strains. Instead, for biodegradable polymer sample, it was observed significant structural changes across multiple absorption bands, suggesting enzyme activity manifested mainly by Aspergillus niger strain. Structural analysis of interdisciplinary research results, lead, to achieving optimal injection molded technology emphasizing technological parameters, in order to obtain food packaging biodegradable products.

  14. 30 CFR 77.1434 - Retirement criteria.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS, SURFACE COAL MINES AND SURFACE WORK AREAS OF UNDERGROUND COAL MINES Personnel... corrosion; (e) Distortion of the rope structure; (f) Heat damage from any source; (g) Diameter reduction due...

  15. Coal systems analysis

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Warwick, P.D.

    This collection of papers provides an introduction to the concept of coal systems analysis and contains examples of how coal systems analysis can be used to understand, characterize, and evaluate coal and coal gas resources. Chapter are: Coal systems analysis: A new approach to the understanding of coal formation, coal quality and environmental considerations, and coal as a source rock for hydrocarbons by Peter D. Warwick. Appalachian coal assessment: Defining the coal systems of the Appalachian Basin by Robert C. Milici. Subtle structural influences on coal thickness and distribution: Examples from the Lower Broas-Stockton coal (Middle Pennsylvanian), Eastern Kentucky Coalmore » Field, USA by Stephen F. Greb, Cortland F. Eble, and J.C. Hower. Palynology in coal systems analysis The key to floras, climate, and stratigraphy of coal-forming environments by Douglas J. Nichols. A comparison of late Paleocene and late Eocene lignite depositional systems using palynology, upper Wilcox and upper Jackson Groups, east-central Texas by Jennifer M.K. O'Keefe, Recep H. Sancay, Anne L. Raymond, and Thomas E. Yancey. New insights on the hydrocarbon system of the Fruitland Formation coal beds, northern San Juan Basin, Colorado and New Mexico, USA by W.C. Riese, William L. Pelzmann, and Glen T. Snyder.« less

  16. Bioprocessing of lignite coals using reductive microorganisms

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Crawford, D.L.

    In order to convert lignite coals into liquid fuels, gases or chemical feedstock, the macromolecular structure of the coal must be broken down into low molecular weight fractions prior to further modification. Our research focused on this aspect of coal bioprocessing. We isolated, characterized and studied the lignite coal-depolymerizing organisms Streptomyces viridosporus T7A, Pseudomonas sp. DLC-62, unidentified bacterial strain DLC-BB2 and Gram-positive Bacillus megaterium strain DLC-21. In this research we showed that these bacteria are able to solubilize and depolymerize lignite coals using a combination of biological mechanisms including the excretion of coal solublizing basic chemical metabolites and extracellular coalmore » depolymerizing enzymes.« less

  17. Biosolubilization of coal by Candida in glucose limited cultures

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mitter, J.; Guillory, L.; Bose, N.K.

    1990-01-01

    Coal biodegradation is attracting the attention of many workers because of its significance for efficient bioconversion of coal into useful chemicals. The authors work is based upon the beneficiation of a fungus (candida) on subbituminous coal. Candida was grown on both solid and liquid sabouraud medium and the coal solubilizing activity was studied at varying glucose concentration and temperature. Lower glucose concentration and higher temperature enhanced coal solubilizing activity by this fungus. Preliminary work has begun on analyzing organic extractions (alumina chromatography) of the liquid produced after microbial solubilization, including elemental analysis, solubility, molecular weights and chemical structure. This preliminarymore » work suggests that the candida could metabolize naturally occurring coal as substrate.« less

  18. Biological solubilization of low-rank coal

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Cohen, M.S.

    1991-07-01

    Low-ranked coals have been solubilized using cell-free extracts derived from liquid cultures of the white-rot fungus Trametes versicolor. The coal solubilizing agent (CSA) has been separated from the broth components and purified by several analytical techniques including rotary evaporation, reverse osmosis, and solvent extraction. The recrystallized CSA retains coal solubilizing activity. Results from polarography, FTIR, and x-ray crystallography confirm that the purified CSA crystals responsible for coal-solubilization are ammonium oxalate monohydrate. The mechanism of solubilization has been deduced to involve removal of divalent cations (particularly iron FE(III)) from low-rank coals. This is followed by dissolution of the macromolecular coal structure.more » 38 figs., 9 tabs.« less

  19. Tension modulates actin filament polymerization mediated by formin and profilin

    PubMed Central

    Courtemanche, Naomi; Lee, Ja Yil; Pollard, Thomas D.; Greene, Eric C.

    2013-01-01

    Formins promote processive elongation of actin filaments for cytokinetic contractile rings and other cellular structures. In vivo, these structures are exposed to tension, but the effect of tension on these processes was unknown. Here we used single-molecule imaging to investigate the effects of tension on actin polymerization mediated by yeast formin Bni1p. Small forces on the filaments dramatically slowed formin-mediated polymerization in the absence of profilin, but resulted in faster polymerization in the presence of profilin. We propose that force shifts the conformational equilibrium of the end of a filament associated with formin homology 2 domains toward the closed state that precludes polymerization, but that profilin–actin associated with formin homology 1 domains reverses this effect. Thus, physical forces strongly influence actin assembly by formin Bni1p. PMID:23716666

  20. An insight into polymerization-induced self-assembly by dissipative particle dynamics simulation.

    PubMed

    Huang, Feng; Lv, Yisheng; Wang, Liquan; Xu, Pengxiang; Lin, Jiaping; Lin, Shaoliang

    2016-08-14

    Polymerization-induced self-assembly is a one-pot route to produce concentrated dispersions of block copolymer nano-objects. Herein, dissipative particle dynamics simulations with a reaction model were employed to investigate the behaviors of polymerization-induced self-assembly. The polymerization kinetics in the polymerization-induced self-assembly were analyzed by comparing with solution polymerization. It was found that the polymerization rate enhances in the initial stage and decreases in the later stage. In addition, the effects of polymerization rate, length of macromolecular initiators, and concentration on the aggregate morphologies and formation pathway were studied. The polymerization rate and the length of the macromolecular initiators are found to have a marked influence on the pathway of the aggregate formations and the final structures. Morphology diagrams were mapped correspondingly. A comparison between simulation results and experimental findings is also made and an agreement is shown. This work can enrich our knowledge about polymerization-induced self-assembly.

  1. Coalbed methane accumulation and dissipation patterns: A Case study of the Junggar Basin, NW China

    NASA Astrophysics Data System (ADS)

    Li, Xin; Fu, Xuehai; Yang, Xuesong; Ge, Yanyan; Quan, Fangkai

    2018-07-01

    The Junggar Basin is a potential replacement area of coalbed methane (CBM) development in China. To improve the efficiency of CBM exploration, we investigated CBM accumulation and dissipation patterns of coal profiles located in the northwestern, southern, eastern, and central Junggar Basin based on the following criteria: burial depth, hydrogeological zone, CBM origin, CBM phase, and CBM migration type. We identified four types of CBM accumulation patterns: (1) a self-sourcing CBM pattern containing adsorbed gas of biogenic origin from shallow-depth coal within a weak runoff zone; (2) an endogenic migration pattern containing adsorbed gas of thermogenic origin from the medium and deep coals within a stagnant zone; (3) an exogenic migration pattern containing adsorbed gas of thermogenic origin from deep coal within a stagnant zone; and (4) an exogenic migration pattern containing adsorbed and free gas of thermogenic origin from ultra-deep coal within a stagnant zone. We also identified two types of CBM dissipation patterns: (1) shallow-depth coal within a runoff zone with mixed origin CBM; and (2) shallow and medium-deep coal seams with mixed origin CBM. CBM migration in low-rank coals was more substantial than that adsorbed in high-rank coal. CBM in shallow coal could easily escape, in the absence of closed structures or hydrogeological seals. CBM reservoirs occurred in deep coal where oversaturated gas may accumulate. Future exploration should focus on gas-water sealing structures in shallow coalbeds. CBM that occurred in adsorbed and free phases and other unconventional natural gas dominated by free gas in the coal stratum should be co-explored and co-developed.

  2. 82. CANAL WEST OF LOCK 12 EAST NEAR BOONTON. STORAGE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    82. CANAL WEST OF LOCK 12 EAST NEAR BOONTON. STORAGE BUILDING AND CHUTE ON LEFT SIDE OF CANAL MAY BE A COAL FACILITY. COAL WOULD BE UNLOADED FROM THE BOAT AND PASSED UP THE CHUTE INTO THE COAL STORAGE BIN. COAL COULD THEN BE LOADED INTO WAGONS FROM THE BOTTOM OF THE BIN ON THE OPPOSITE SIDE OF THE STRUCTURE WHEN NECESSARY. - Morris Canal, Phillipsburg, Warren County, NJ

  3. A bacterial hydrogen-dependent CO2 reductase forms filamentous structures.

    PubMed

    Schuchmann, Kai; Vonck, Janet; Müller, Volker

    2016-04-01

    Interconversion of CO2 and formic acid is an important reaction in bacteria. A novel enzyme complex that directly utilizes molecular hydrogen as electron donor for the reversible reduction of CO2 has recently been identified in the Wood-Ljungdahl pathway of an acetogenic bacterium. This pathway is utilized for carbon fixation as well as energy conservation. Here we describe the further characterization of the quaternary structure of this enzyme complex and the unexpected behavior of this enzyme in polymerizing into filamentous structures. Polymerization of metabolic enzymes into similar structures has been observed only in rare cases but the increasing number of examples point towards a more general characteristic of enzyme functioning. Polymerization of the purified enzyme into ordered filaments of more than 0.1 μm in length was only dependent on the presence of divalent cations. Polymerization was a reversible process and connected to the enzymatic activity of the oxygen-sensitive enzyme with the filamentous form being the most active state. © 2016 Federation of European Biochemical Societies.

  4. Kinetics and mechanism of catalytic hydroprocessing of components of coal-derived liquids. Sixteenth quarterly report, February 16, 1983-May 15, 1983.

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gates, B. C.; Olson, H. H.; Schuit, G. C.A.

    1983-08-22

    A new method of structural analysis is applied to a group of hydroliquefied coal samples. The method uses elemental analysis and NMR data to estimate the concentrations of functional groups in the samples. The samples include oil and asphaltene fractions obtained in a series of hydroliquefaction experiments, and a set of 9 fractions separated from a coal-derived oil. The structural characterization of these samples demonstrates that estimates of functional group concentrations can be used to provide detailed structural profiles of complex mixtures and to obtain limited information about reaction pathways. 11 references, 1 figure, 7 tables.

  5. Mineralization Of PAHs In Coal-Tar Impacted Aquifer Sediments And Associated Microbial Community Structure Investigated With FISH

    EPA Science Inventory

    The microbial community structure and mineralization of polycyclic aromatic hydrocarbons (PAHs) in a coal-tar contaminated aquifer were investigated spatially using fluorescence in situ hybridization (FISH) and in laboratory-scale incubations of the aquifer sediments. DAPI-detect...

  6. Research of Energy Substitution Strategy of China

    NASA Astrophysics Data System (ADS)

    Zhang, Lifeng; kai, Chen

    For a long time, China's energy endowment structure determines the production structure and consumption structure of energy are coal-based.This situation is difficult to change for quite a long time. With the rapid economic growth, industrialization and urbanization, the demand for energy, especially for oil, natural gas will continue to increase. But the oil and gas supply can not meet the needs of rapid growth. The most direct way is to import, and imports will be charged by the international energy situation, and will affect energy and economic security. In view of our country abundant coal resources, we can consider to use coal substituting oil and natural gas to reduce dependence on foreign energy, to strengthen energy and economic security. Therefore, using translog production function, the text forecasts substitution elasticity and the marginal substitution rate between the capital, coal, oil and natural gas, and puts forward substitution program.

  7. Visual detection of gas shows from coal core and cuttings using liquid leak detector

    USGS Publications Warehouse

    Barker, C.E.

    2006-01-01

    Portions of core or cutting samples that have active gas shows can be identified by applying a liquid leak detector to the core surface. Although these gas shows can be caused by manmade changes to the coals' internal structure and surface of the core during the coring process, in many cases, the marked gas shows overlie changes in maceral composition, subtle fractures or coal, coal structure and so forth that seemingly are places where natural primary permeability is higher and gas shows would be favored. Given the limited time available for core description before a core is closed in a canister, using the liquid leak detector method to mark gas shows enhances core description by providing a photographic record of places of apparently increased gas flow likely related to enhanced coal permeability that cannot be easily detected otherwise.

  8. Visualization and identification of the structures formed during early stages of fibrin polymerization

    PubMed Central

    Chernysh, Irina N.; Nagaswami, Chandrasekaran

    2011-01-01

    We determined the sequence of events and identified and quantitatively characterized the mobility of moving structures present during the early stages of fibrin-clot formation from the beginning of polymerization to the gel point. Three complementary techniques were used in parallel: spinning-disk confocal microscopy, transmission electron microscopy, and turbidity measurements. At the beginning of polymerization the major structures were monomers, whereas at the middle of the lag period there were monomers, oligomers, protofibrils (defined as structures that consisted of more than 8 monomers), and fibers. At the end of the lag period, there were primarily monomers and fibers, giving way to mainly fibers at the gel point. Diffusion rates were calculated from 2 different results, one based on sizes and another on the velocity of the observed structures, with similar results in the range of 3.8-0.1 μm2/s. At the gel point, the diffusion coefficients corresponded to very large, slow-moving structures and individual protofibrils. The smallest moving structures visible by confocal microscopy during fibrin polymerization were identified as protofibrils with a length of approximately 0.5 μm. The sequence of early events of clotting and the structures present are important for understanding hemostasis and thrombosis. PMID:21248064

  9. A multi-instrumental geochemical study of anomalous uranium enrichment in coal.

    PubMed

    Havelcová, Martina; Machovič, Vladimír; Mizera, Jiří; Sýkorová, Ivana; Borecká, Lenka; Kopecký, Lubomír

    2014-11-01

    Contents of uranium in coals from Odeř in the northernmost part of the Sokolov Basin, Czech Republic, in the vicinity of the well known St. Joachimsthal uranium ore deposits, reach extremely high values. In the present work, coal samples with contents of uranium ranging from 0.02 to 6 wt.% were studied. The study employing a whole complex of analytical techniques has been aimed at identification of changes in the structure of coal organic matter, which are associated with the high contents of uranium in coal. The study includes proximate and ultimate analyses, multielement analysis by instrumental neutron and photon activation analyses, micropetrographic analysis by optical microscopy, ESEM/EDX analysis of mineral matter, infrared and Raman spectroscopies, solvent extraction followed by gas chromatography with mass spectroscopy (GC/MS), and analytical pyrolysis (Py-GC/MS). The study has confirmed previously proposed explanation of uraniferous mineralization in sedimentary carboniferous substances by the mechanism of reduction and fixation of soluble U(VI) (uranyl, UO2(2+)) species (e.g., humic, carbonate/hydroxo/phosphate complexes) by sedimentary organic matter under diagenetic or hydrothermal conditions, and formation of insoluble U(IV) species as phosphate minerals and uraninite. The process is accompanied with alteration and destruction of the coal organic matter. The changes in the structure of coal organic matter involve dehydrogenation and oxidation mainly in the aliphatic, aromatic and hydroxyl structures, and an increase in aromaticity, content of ether bonds, and the degree of coalification. Copyright © 2014 Elsevier Ltd. All rights reserved.

  10. Influence of the microwave irradiation dewatering on the combustion characteristics of Chinese brown coals

    NASA Astrophysics Data System (ADS)

    Ge, Lichao; Feng, Hongcui; Xu, Chang; Zhang, Yanwei; Wang, Zhihua

    2018-02-01

    This study investigates the influence of microwave irradiation on coal composition, pore structure, coal rank, and combustion characteristics of typical brown coals in China. Results show that the upgrading process significantly decreased the inherent moisture, and increased calorific value and fixed carbon content. After upgrading, pore distribution extended to micropore region, oxygen functional groups were reduced and destroyed, and the apparent aromaticity increased suggesting an improvement in the coal rank. Based on thermogravimetric analysis, the combustion processes of upgraded coals were delayed toward the high temperature region, and the temperatures of ignition, peak and burnout increased. Based on the average combustion rate and comprehensive combustion parameter, the upgraded coals performed better compared with raw brown coals and a high rank coal. In ignition and burnout segments, the activation energy increased but exhibited a decrease in the combustion stage.

  11. Supramolecular 1-D polymerization of DNA origami through a dynamic process at the 2-dimensionally confined air-water interface.

    PubMed

    Yonamine, Yusuke; Cervantes-Salguero, Keitel; Minami, Kosuke; Kawamata, Ibuki; Nakanishi, Waka; Hill, Jonathan P; Murata, Satoshi; Ariga, Katsuhiko

    2016-05-14

    In this study, a Langmuir-Blodgett (LB) system has been utilized for the regulation of polymerization of a DNA origami structure at the air-water interface as a two-dimensionally confined medium, which enables dynamic condensation of DNA origami units through variation of the film area at the macroscopic level (ca. 10-100 cm(2)). DNA origami sheets were conjugated with a cationic lipid (dioctadecyldimethylammonium bromide, 2C18N(+)) by electrostatic interaction and the corresponding LB-film was prepared. By applying dynamic pressure variation through compression-expansion processes, the lipid-modified DNA origami sheets underwent anisotropic polymerization forming a one-dimensionally assembled belt-shaped structure of a high aspect ratio although the thickness of the polymerized DNA origami was maintained at the unimolecular level. This approach opens up a new field of mechanical induction of the self-assembly of DNA origami structures.

  12. Rapid Engineering of Three-Dimensional, Multicellular Tissues With Polymeric Scaffolds

    NASA Technical Reports Server (NTRS)

    Gonda, Steve R.; Jordan, Jacqueline; Fraga, Denise N.

    2007-01-01

    A process has been developed for the rapid tissue engineering of multicellular-tissue-equivalent assemblies by the controlled enzymatic degradation of polymeric beads in a low-fluid-shear bioreactor. In this process, the porous polymeric beads serve as temporary scaffolds to support the assemblies of cells in a tissuelike 3D configuration during the critical initial growth phases of attachment of anchorage-dependent cells, aggregation of the cells, and formation of a 3D extracellular matrix. Once the cells are assembled into a 3D array and enmeshed in a structural supportive 3D extracellular matrix (ECM), the polymeric scaffolds can be degraded in the low-fluid-shear environment of the NASA-designed bioreactor. The natural 3D tissuelike assembly, devoid of any artificial support structure, is maintained in the low-shear bioreactor environment by the newly formed natural cellular/ECM. The elimination of the artificial scaffold allows normal tissue structure and function.

  13. Bioprocessing of lignite coals using reductive microorganisms. Final technical report, September 30, 1988--March 29, 1992

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Crawford, D.L.

    In order to convert lignite coals into liquid fuels, gases or chemical feedstock, the macromolecular structure of the coal must be broken down into low molecular weight fractions prior to further modification. Our research focused on this aspect of coal bioprocessing. We isolated, characterized and studied the lignite coal-depolymerizing organisms Streptomyces viridosporus T7A, Pseudomonas sp. DLC-62, unidentified bacterial strain DLC-BB2 and Gram-positive Bacillus megaterium strain DLC-21. In this research we showed that these bacteria are able to solubilize and depolymerize lignite coals using a combination of biological mechanisms including the excretion of coal solublizing basic chemical metabolites and extracellular coalmore » depolymerizing enzymes.« less

  14. Ground state structure of high-energy-density polymeric carbon monoxide

    NASA Astrophysics Data System (ADS)

    Xia, Kang; Sun, Jian; Pickard, Chris J.; Klug, Dennis D.; Needs, Richard J.

    2017-04-01

    Crystal structure prediction methods and first-principles calculations have been used to explore low-energy structures of carbon monoxide (CO). Contrary to the standard wisdom, the most stable structure of CO at ambient pressure was found to be a polymeric structure of P n a 21 symmetry rather than a molecular solid. This phase is formed from six-membered (four carbon + two oxygen) rings connected by C=C double bonds with two double-bonded oxygen atoms attached to each ring. Interestingly, the polymeric P n a 21 phase of CO has a much higher energy density than trinitrotoluene (TNT). On compression to about 7 GPa, P n a 21 is found to transform into another chainlike phase of C c symmetry which has similar ring units to P n a 21 . On compression to 12 GPa, it is energetically favorable for CO to polymerize into a purely single bonded C m c a phase, which is stable over a wide pressure range and transforms into the previously known C m c m phase at around 100 GPa. Thermodynamic stability of these structures was verified using calculations with different density functionals, including hybrid and van der Waals corrected functionals.

  15. The effects of pore structure on the behavior of water in lignite coal and activated carbon.

    PubMed

    Nwaka, Daniel; Tahmasebi, Arash; Tian, Lu; Yu, Jianglong

    2016-09-01

    The effects of physical structure (pore structure) on behavior of water in lignite coal and activated carbon (AC) samples were investigated by using Differential Scanning Calorimetry (DSC) and low-temperature X-ray diffraction (XRD) techniques. AC samples with different pore structures were prepared at 800°C in steam and the results were compared with that of parent lignite coal. The DSC results confirmed the presence of two types of freezable water that freeze at -8°C (free water) and -42°C (freezable bound water). A shift in peak position of free water (FW) towards lower temperature was observed in AC samples compared to the lignite coal with decreasing water loading. The amount of free water (FW) increased with increasing gasification conversion. The amounts of free and freezable bound water (FBW) in AC samples were calculated and correlated to pore volume and average pore size. The amount of FW in AC samples is well correlated to the pore volume and average pore size of the samples, while an opposite trend was observed for FBW. The low-temperature XRD analysis confirmed the existence of non-freezable water (NFW) in coal and AC with the boundary between the freezable and non-freezable water (NFW) determined. Copyright © 2016 Elsevier Inc. All rights reserved.

  16. 30 CFR 780.12 - Operation plan: Existing structures.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... each existing structure proposed to be used in connection with or to facilitate the surface coal mining... which describe its current condition; (3) Approximate dates on which construction of the existing... proposed to be modified or reconstructed for use in connection with or to facilitate the surface coal...

  17. 30 CFR 784.12 - Operation plan: Existing structures.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... each existing structure proposed to be used in connection with or to facilitate the surface coal mining... which describe its current condition; (3) Approximate dates on which construction of the existing... proposed to be modified or reconstructed for use in connection with or to facilitate the surface coal...

  18. XAFS SPECTROSCOPY ANALYSIS OF SELECTED HAP ELEMENTS IN FINE PM DERIVED FROM COAL COMBUSTION

    EPA Science Inventory

    X-ray absorption fine structure (XAFS) spectroscopy has been used to investigate the valence states and molecular structures of sulfur (S), chromium (Cr), arsenic (As), and zinc (Zn) in fine particulate matter (PM) separated from coal flyash produced in a realistic combustion sys...

  19. 30 CFR 77.403 - Mobile equipment; falling object protective structures (FOPS).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Mobile equipment; falling object protective... AREAS OF UNDERGROUND COAL MINES Safeguards for Mechanical Equipment § 77.403 Mobile equipment; falling... underground coal mines shall be provided with substantial falling object protective structures (FOPS). FOPS...

  20. 30 CFR 77.403 - Mobile equipment; falling object protective structures (FOPS).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Mobile equipment; falling object protective... AREAS OF UNDERGROUND COAL MINES Safeguards for Mechanical Equipment § 77.403 Mobile equipment; falling... underground coal mines shall be provided with substantial falling object protective structures (FOPS). FOPS...

  1. 30 CFR 77.403 - Mobile equipment; falling object protective structures (FOPS).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Mobile equipment; falling object protective... AREAS OF UNDERGROUND COAL MINES Safeguards for Mechanical Equipment § 77.403 Mobile equipment; falling... underground coal mines shall be provided with substantial falling object protective structures (FOPS). FOPS...

  2. Effects of polymerization and nucleotide identity on the conformational dynamics of the bacterial actin homolog MreB

    PubMed Central

    Colavin, Alexandre; Hsin, Jen; Huang, Kerwyn Casey

    2014-01-01

    The assembly of protein filaments drives many cellular processes, from nucleoid segregation, growth, and division in single cells to muscle contraction in animals. In eukaryotes, shape and motility are regulated through cycles of polymerization and depolymerization of actin cytoskeletal networks. In bacteria, the actin homolog MreB forms filaments that coordinate the cell-wall synthesis machinery to regulate rod-shaped growth and contribute to cellular stiffness through unknown mechanisms. Like actin, MreB is an ATPase and requires ATP to polymerize, and polymerization promotes nucleotide hydrolysis. However, it is unclear whether other similarities exist between MreB and actin because the two proteins share low sequence identity and have distinct cellular roles. Here, we use all-atom molecular dynamics simulations to reveal surprising parallels between MreB and actin structural dynamics. We observe that MreB exhibits actin-like polymerization-dependent structural changes, wherein polymerization induces flattening of MreB subunits, which restructures the nucleotide-binding pocket to favor hydrolysis. MreB filaments exhibited nucleotide-dependent intersubunit bending, with hydrolyzed polymers favoring a straighter conformation. We use steered simulations to demonstrate a coupling between intersubunit bending and the degree of flattening of each subunit, suggesting cooperative bending along a filament. Taken together, our results provide molecular-scale insight into the diversity of structural states of MreB and the relationships among polymerization, hydrolysis, and filament properties, which may be applicable to other members of the broad actin family. PMID:24550504

  3. Effects of polymerization and nucleotide identity on the conformational dynamics of the bacterial actin homolog MreB.

    PubMed

    Colavin, Alexandre; Hsin, Jen; Huang, Kerwyn Casey

    2014-03-04

    The assembly of protein filaments drives many cellular processes, from nucleoid segregation, growth, and division in single cells to muscle contraction in animals. In eukaryotes, shape and motility are regulated through cycles of polymerization and depolymerization of actin cytoskeletal networks. In bacteria, the actin homolog MreB forms filaments that coordinate the cell-wall synthesis machinery to regulate rod-shaped growth and contribute to cellular stiffness through unknown mechanisms. Like actin, MreB is an ATPase and requires ATP to polymerize, and polymerization promotes nucleotide hydrolysis. However, it is unclear whether other similarities exist between MreB and actin because the two proteins share low sequence identity and have distinct cellular roles. Here, we use all-atom molecular dynamics simulations to reveal surprising parallels between MreB and actin structural dynamics. We observe that MreB exhibits actin-like polymerization-dependent structural changes, wherein polymerization induces flattening of MreB subunits, which restructures the nucleotide-binding pocket to favor hydrolysis. MreB filaments exhibited nucleotide-dependent intersubunit bending, with hydrolyzed polymers favoring a straighter conformation. We use steered simulations to demonstrate a coupling between intersubunit bending and the degree of flattening of each subunit, suggesting cooperative bending along a filament. Taken together, our results provide molecular-scale insight into the diversity of structural states of MreB and the relationships among polymerization, hydrolysis, and filament properties, which may be applicable to other members of the broad actin family.

  4. Cohering Behavior of Coal Ash with Pellet Scrap Powder and Relationship Between Coal Ash and Kiln Ringing

    NASA Astrophysics Data System (ADS)

    Yang, Yong-bin; Zhang, Yan; Zhong, Qiang; Jiang, Tao; Li, Qian; Xu, Bin

    The occurrence of different ringing behaviors in oxidized pellet kiln for two kinds of coal (A and B) with similar properties, is difficult to explain based on the relationship between kiln ringing and coal properties. In this paper, the interaction of coal ash with pellet scrap powder was considered by studying the cohering behavior of powders consisting of them. The results showed that the cohering briquette strength of pellet scrap powder increased considerably when mixed with a small amount of coal ash; a maximum could be reached when the mass percent ratio of coal ash was 1.5%; the strength of powder mixed with coal B ash was always higher in same firing system. This obviously illustrated that coal B caused a more serious ringing problem. The relevant mechanism was that the stronger reactivity of coal B ash made cohering briquette have a more perfect crystallization and a more compact structure.

  5. 30 CFR 77.403-1 - Mobile equipment; rollover protective structures (ROPS).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... WORK AREAS OF UNDERGROUND COAL MINES Safeguards for Mechanical Equipment § 77.403-1 Mobile equipment... surface coal mines or the surface work areas of underground coal mines shall be provided with rollover... complying with paragraph (d) (1) (iii) (A) of this section. Stresses shall not exceed the ultimate strength...

  6. 30 CFR 77.403-1 - Mobile equipment; rollover protective structures (ROPS).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... WORK AREAS OF UNDERGROUND COAL MINES Safeguards for Mechanical Equipment § 77.403-1 Mobile equipment... surface coal mines or the surface work areas of underground coal mines shall be provided with rollover... complying with paragraph (d) (1) (iii) (A) of this section. Stresses shall not exceed the ultimate strength...

  7. 49 CFR 1242.27 - Coal marine terminals, ore marine terminals, TOFC/COFC terminals, other marine terminals, motor...

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 9 2014-10-01 2014-10-01 false Coal marine terminals, ore marine terminals, TOFC/COFC terminals, other marine terminals, motor vehicle loading and distribution facilities, and... Structures § 1242.27 Coal marine terminals, ore marine terminals, TOFC/COFC terminals, other marine terminals...

  8. 49 CFR 1242.27 - Coal marine terminals, ore marine terminals, TOFC/COFC terminals, other marine terminals, motor...

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 9 2013-10-01 2013-10-01 false Coal marine terminals, ore marine terminals, TOFC/COFC terminals, other marine terminals, motor vehicle loading and distribution facilities, and... Structures § 1242.27 Coal marine terminals, ore marine terminals, TOFC/COFC terminals, other marine terminals...

  9. 49 CFR 1242.27 - Coal marine terminals, ore marine terminals, TOFC/COFC terminals, other marine terminals, motor...

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 9 2012-10-01 2012-10-01 false Coal marine terminals, ore marine terminals, TOFC/COFC terminals, other marine terminals, motor vehicle loading and distribution facilities, and... Structures § 1242.27 Coal marine terminals, ore marine terminals, TOFC/COFC terminals, other marine terminals...

  10. 49 CFR 1242.27 - Coal marine terminals, ore marine terminals, TOFC/COFC terminals, other marine terminals, motor...

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 9 2011-10-01 2011-10-01 false Coal marine terminals, ore marine terminals, TOFC/COFC terminals, other marine terminals, motor vehicle loading and distribution facilities, and... Structures § 1242.27 Coal marine terminals, ore marine terminals, TOFC/COFC terminals, other marine terminals...

  11. 49 CFR 1242.27 - Coal marine terminals, ore marine terminals, TOFC/COFC terminals, other marine terminals, motor...

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 9 2010-10-01 2010-10-01 false Coal marine terminals, ore marine terminals, TOFC/COFC terminals, other marine terminals, motor vehicle loading and distribution facilities, and... Structures § 1242.27 Coal marine terminals, ore marine terminals, TOFC/COFC terminals, other marine terminals...

  12. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hur, Tae-Bong; Fazio, James; Romanov, Vyacheslav

    Due to increasing atmospheric CO2 concentrations causing the global energy and environmental crises, geological sequestration of carbon dioxide is now being actively considered as an attractive option to mitigate greenhouse gas emissions. One of the important strategies is to use deep unminable coal seams, for those generally contain significant quantities of coal bed methane that can be recovered by CO2 injection through enhanced coal bed natural gas production, as a method to safely store CO2. It has been well known that the adsorbing CO2 molecules introduce structural deformation, such as distortion, shrinkage, or swelling, of the adsorbent of coal organicmore » matrix. The accurate investigations of CO2 sorption capacity as well as of adsorption behavior need to be performed under the conditions that coals deform. The U.S. Department of Energy-National Energy Technology Laboratory and Regional University Alliance are conducting carbon dioxide sorption isotherm experiments by using manometric analysis method for estimation of CO2 sorption capacity of various coal samples and are constructing a gravimetric apparatus which has a visual window cell. The gravimetric apparatus improves the accuracy of carbon dioxide sorption capacity and provides feasibility for the observation of structural deformation of coal sample while carbon dioxide molecules interact with coal organic matrix. The CO2 sorption isotherm measurements have been conducted for moist and dried samples of the Central Appalachian Basin (Russell County, VA) coal seam, received from the SECARB partnership, at the temperature of 55 C.« less

  13. High temperature alkali corrosion of ceramics in coal gas: Final report

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Pickrell, G.R.; Sun, T.; Brown, J.J. Jr.

    1994-12-31

    There are several ceramic materials which are currently being considered for use as structural elements in coal combustion and coal conversion systems because of their thermal and mechanical properties. These include alumina (refractories, membranes, heat engines); silicon carbide and silicon nitride (turbine engines, internal combustion engines, heat exchangers, particulate filters); zirconia (internal combustion engines, turbine engines, refractories); and mullite and cordierite (particulate filters, refractories, heat exchangers). High temperature alkali corrosion has been known to cause premature failure of ceramic components used in advanced high temperature coal combustion systems such as coal gasification and clean-up, coal fired gas turbines, and highmore » efficiency heat engines. The objective of this research is to systematically evaluate the alkali corrosion resistance of the most commonly used structural ceramics including silicon carbide, silicon nitride, cordierite, mullite, alumina, aluminum titanate, and zirconia. The study consists of identification of the alkali reaction products and determination of the kinetics of the alkali reactions as a function of temperature and time. 145 refs., 29 figs., 12 tabs.« less

  14. Coal liquefaction process streams characterization and evaluation: Analysis of Black Thunder coal and liquefaction products from HRI Bench Unit Run CC-15

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Pugmire, R.J.; Solum, M.S.

    This study was designed to apply {sup 13}C-nuclear magnetic resonance (NMR) spectrometry to the analysis of direct coal liquefaction process-stream materials. {sup 13}C-NMR was shown to have a high potential for application to direct coal liquefaction-derived samples in Phase II of this program. In this Phase III project, {sup 13}C-NMR was applied to a set of samples derived from the HRI Inc. bench-scale liquefaction Run CC-15. The samples include the feed coal, net products and intermediate streams from three operating periods of the run. High-resolution {sup 13}C-NMR data were obtained for the liquid samples and solid-state CP/MAS {sup 13}C-NMR datamore » were obtained for the coal and filter-cake samples. The {sup 1}C-NMR technique is used to derive a set of twelve carbon structural parameters for each sample (CONSOL Table A). Average molecular structural descriptors can then be derived from these parameters (CONSOL Table B).« less

  15. Co-gasification of coal and biomass: Synergy, characterization and reactivity of the residual char.

    PubMed

    Hu, Junhao; Shao, Jingai; Yang, Haiping; Lin, Guiying; Chen, Yingquan; Wang, Xianhua; Zhang, Wennan; Chen, Hanping

    2017-11-01

    The synergy effect between coal and biomass in their co-gasification was studied in a vertical fixed bed reactor, and the physic-chemical structural characteristics and gasification reactivity of the residual char obtained from co-gasification were also investigated. The results shows that, conversion of the residual char and tar into gas is enhanced due to the synergy effect between coal and biomass. The physical structure of residual char shows more pore on coal char when more biomass is added in the co-gasification. The migration of inorganic elements between coal and biomass was found, the formation and competitive role of K 2 SiO 3 , KAlSiO 4 , and Ca 3 Al 2 (SiO 4 ) 3 is a mechanism behind the synergy. The graphization degree is enhanced but size of graphite crystallite in the residual char decreases with biomass blending ratio increasing. TGA results strongly suggest the big difference in the reactivity of chars derived from coal and biomass in spite of influence from co-gasification. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Enhanced linearly polarized lasing emission from nanoimprinted surface-emitting distributed feedback laser based on polymeric liquid crystals

    NASA Astrophysics Data System (ADS)

    Jeong, Soon Moon; Ha, Na Young; Chee, Mu Guen; Araoka, Fumito; Ishikawa, Ken; Takezoe, Hideo; Nishimura, Suzushi; Suzaki, Goro

    2008-12-01

    The authors have demonstrated the enhancement of linearly polarized lasing emission intensity using a structure made by a simple fabrication process. The enhanced lasing is achieved using a nanoimprinted distributed feedback structure together with spin-coated polymeric liquid crystals. The backward linearly TE-polarized lasing emission is transformed to left-handed circularly polarized light (L-CPL) by employing a dye-doped polymeric nematic liquid crystal (PNLC) film as a (-1/4)λ[=(3/4)λ] plate. The L-CPL is effectively reflected by a L-polymeric cholesteric liquid crystal film as a reflector and transformed back to TE-polarized light by the PNLC film; as a result one-directional emission intensity is enhanced.

  17. Investigation of Intrinsic and External Factors Contributing to the Occurrence of Coal Bumps in the Mining Area of Western Beijing, China

    NASA Astrophysics Data System (ADS)

    Wang, Hongwei; Jiang, Yaodong; Xue, Sheng; Pang, Xufeng; Lin, Zhinan; Deng, Daixin

    2017-04-01

    An investigation has been made to relate the occurrence of coal bumps to specific geological and mining conditions to the mining area of western Beijing. This investigation demonstrates that the high frequency of coal bumps in this area is due to four localized conditions, namely intrinsic coal properties, the presence of overturned strata and thrust faults, high in situ stress and the extraction of coal from island mining faces. Laboratory tests of coal samples indicated that the coals have a short duration of dynamic fracture, high bursting energy and high elastic strain energy, indicating that the coal is intrinsically prone to the occurrence of coal bumps. This investigation has also revealed that there are overturned strata and well-developed large- and medium-scale thrust faults in this area, and the presence of these structures results in plastic flow, severe discontinuities, rapid changes in overburden thickness and dipping of the coal seams. Well-developed secondary fold structures are also present in the axes and limbs of the primary folds. The instability of thrust faults, in combination with large-scale intrusion of igneous rocks, is closely associated with sudden roof breaking and induces sharp variations in electromagnetic radiation (EMR) and micro-seismic signals, which could be used to help predict coal bumps. In situ stress tests in the mining area demonstrate that the maximum and minimum principal stresses are nearly horizontal and that the intermediate principal stress is approximately vertical. The in situ stress level in the area is higher than the average in the Beijing area, North China and mainland China. In addition to the presence of overturned strata and thrust faults and high in situ stress levels, another external factor contributing to the frequency of coal bumps is coal extraction from island mining faces in this area. Island mining faces experience intermittent mining-induced abutment stress when a fault exists at one side of the island mining face due to reactivation of the fault, and this stress redistribution increases the likelihood of coal bumps during coal extraction from island mining faces.

  18. Fungal biodegradation of hard coal by a newly reported isolate, Neosartorya fischeri.

    PubMed

    Igbinigie, Eric E; Aktins, Simon; van Breugel, Yvonne; van Dyke, Susan; Davies-Coleman, Michael T; Rose, Peter D

    2008-11-01

    Cynodon dactylon (Bermuda grass) has been observed to grow sporadically on the surface of coal dumps in the Witbank coal mining area of South Africa. Root zone investigation indicated that a number of fungal species may be actively involved in the biodegradation of hard coal, thus enabling the survival of the plant, through mutualistic interaction, in this extreme environment. In an extensive screening program of over two thousand samples, the Deuteromycete, Neosartorya fischeri, was isolated and identified. The biodegradation of coal by N. fischeri was tested in flask studies and in a perfusion fixed-bed bioreactor used to simulate the coal dump environment. The performance of N. fischeri was compared to Phanaerochaete chrysosporium and Trametes (Polyporus) versicolor, previously described in coal biodegradation studies. Fourier transform infrared spectrometry and pyrolysis gas chromatography mass spectrometry of the biodegradation product indicated oxidation of the coal surface and nitration of the condensed aromatic structures of the coal macromolecule as possible reaction mechanisms in N. fischeri coal biodegradation. This is a first report of N. fischeri-mediated coal biodegradation and, in addition to possible applications in coal biotechnology, the findings may enable development of sustainable technologies in coal mine rehabilitation.

  19. Functionalized ormosil scaffolds processed by direct laser polymerization for application in tissue engineering

    NASA Astrophysics Data System (ADS)

    Matei, A.; Schou, J.; Canulescu, S.; Zamfirescu, M.; Albu, C.; Mitu, B.; Buruiana, E. C.; Buruiana, T.; Mustaciosu, C.; Petcu, I.; Dinescu, M.

    2013-08-01

    Synthesized N,N'-(methacryloyloxyethyl triehtoxy silyl propyl carbamoyl-oxyhexyl)-urea hybrid methacrylate was polymerized by direct laser polymerization using femtosecond laser pulses with the aim of using it for subsequent applications in tissue engineering. The as-obtained scaffolds were modified either by low pressure argon plasma treatment or by covering the structures with two different proteins (lysozyme, fibrinogen). For improved adhesion, the proteins were deposited by matrix assisted pulsed laser evaporation technique. The functionalized structures were tested in mouse fibroblasts culture and the cells morphology, proliferation, and attachment were analyzed.

  20. Knowledge modeling of coal mining equipments based on ontology

    NASA Astrophysics Data System (ADS)

    Zhang, Baolong; Wang, Xiangqian; Li, Huizong; Jiang, Miaomiao

    2017-06-01

    The problems of information redundancy and sharing are universe in coal mining equipment management. In order to improve the using efficiency of knowledge of coal mining equipments, this paper proposed a new method of knowledge modeling based on ontology. On the basis of analyzing the structures and internal relations of coal mining equipment knowledge, taking OWL as ontology construct language, the ontology model of coal mining equipment knowledge is built with the help of Protégé 4.3 software tools. The knowledge description method will lay the foundation for the high effective knowledge management and sharing, which is very significant for improving the production management level of coal mining enterprises.

  1. Benthic invertebrate communities and their responses to selected environmental factors in the Kanawha River basin, West Virginia, Virginia, and North Carolina

    USGS Publications Warehouse

    Chambers, Douglas B.; Messinger, Terence

    2001-01-01

    The effects of selected environmental factors on the composition and structure of benthic invertebrate communities in the Kanawha River Basin of West Virginia, Virginia and North Carolina were investigated in 1997 and 1998. Environmental factors investigated include physiography, land-use pattern, streamwater chemistry, streambed- sediment chemistry, and habitat characteristics. Land-use patterns investigated include coal mining, agriculture, and low intensity rural-residential patterns, at four main stem and seven tributary sites throughout the basin. Of the 37 sites sampled, basin size and physiography most strongly affected benthic invertebrate-community structure. Land-use practices also affected invertebrate community structure in these basins. The basins that differed most from the minimally affected reference condition were those basins in which coal mining was the dominant nonforest land use, as determined by comparing invertebrate- community metric values among sites. Basins in which agriculture was important were more similar to the reference condition. The effect of coal mining upon benthic invertebrate communities was further studied at 29 sites and the relations among invertebrate communities and the selected environmental factors of land use, streamwater chemistry, streambed- sediment chemistry, and habitat characteristics analyzed. Division of coal-mining synoptic-survey sites based on invertebrate-community composition resulted in two groups?one with more than an average production of 9,000 tons of coal per square mile per year since 1980, and one with lesser or no recent coal production. The group with significant recent coal production showed higher levels of community impairment than the group with little or no recent coal production. Median particle size of streambed sediment, and specific conductance and sulfate concentration of streamwater were most strongly correlated with effects on invertebrate communities. These characteristics were related to mining intensity, as measured by thousands of tons of coal produced per square mile of drainage area.

  2. Effects of Prepolymerized Particle Size and Polymerization Kinetics on Volumetric Shrinkage of Dental Modeling Resins

    PubMed Central

    Ha, Jung-Yun; Chun, Ju-Na; Son, Jun Sik; Kim, Kyo-Han

    2014-01-01

    Dental modeling resins have been developed for use in areas where highly precise resin structures are needed. The manufacturers claim that these polymethyl methacrylate/methyl methacrylate (PMMA/MMA) resins show little or no shrinkage after polymerization. This study examined the polymerization shrinkage of five dental modeling resins as well as one temporary PMMA/MMA resin (control). The morphology and the particle size of the prepolymerized PMMA powders were investigated by scanning electron microscopy and laser diffraction particle size analysis, respectively. Linear polymerization shrinkage strains of the resins were monitored for 20 minutes using a custom-made linometer, and the final values (at 20 minutes) were converted into volumetric shrinkages. The final volumetric shrinkage values for the modeling resins were statistically similar (P > 0.05) or significantly larger (P < 0.05) than that of the control resin and were related to the polymerization kinetics (P < 0.05) rather than the PMMA bead size (P = 0.335). Therefore, the optimal control of the polymerization kinetics seems to be more important for producing high-precision resin structures rather than the use of dental modeling resins. PMID:24779020

  3. Crowding-out effect of coal industry investment in coal mining area: taking Shanxi province in China as a case.

    PubMed

    Li, Li; Lei, Yalin; Xu, Qun; Wu, Sanmang; Yan, Dan; Chen, Jiabin

    2017-10-01

    The rapid development of coal industry in Shanxi province in China has important effects on its economic development. A large amount of money has been invested into the coal industry and other related industries during the recent years. However, research on the investment effect of Shanxi's coal industry was rare. In order to analyze the investment effect of coal industry, based on the crowding-out effect model, cointegration test, and the data available in Shanxi Statistical Yearbooks, this paper calculates the effect between coal industry investment and other 17 industry investment. The results show that the investment of coal industry produces crowding-out effect on food industry, building materials industry, and machinery industry. Increasing 1% of the coal industry investment can reduce 0.25% of the food industry investment, or 0.6% of building materials industry investment, or 0.52% of the machinery industry investment, which implies that Shanxi province should adjust coal industrial structure, promote the balance development of coal industry and other industries, so as to promote its economic growth.

  4. Morphology and systematics of cordaites of Pennsylvanian coal swamps of Euramerica

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Costanza, S.H.

    1984-01-01

    Cordaites are extinct coniferophytic shrubs and trees of the Late Paleozoic. They were most prominent in tropical coal swamps existing from the Westphalian A-B boundary of Western Europe to the middle Desmoinesian (Westphalian D) of midcontinental United States. Structurally preserved coal-ball cordaites from Pennsylvanian Euramerican coals were analyzed for whole plant understanding, morphological variation, and indications of ecological tolerances. Organ assemblages for individual species were established from coals where coal balls contain single cordaitean seed species. Cordaitean organ assemblages were stratigraphically compiled, compared, and cross-correlated. Cordaitean assemblage comparisons of most known coals with coal balls confirm organ assemblages established formore » Pennsylvanioxylon, and indicate that Mesoxylon bore Mitrospermum ovules. Mesoxylon and Pennsylvanioxylon are the only coal-swamp Pennsylvanian cordaitean genera recognized herein. They are consistently different in stem xylem development, leaf and branch trace formation, in amount of cortical sclerenchyma and associated organs. Morphology of coal-swamp cordaites, especially cortical aerenchyma in Pennsylvanioxylon, indicates semi-aquatic ecological adaptation. Coal-swamp cordaitean lineages may demonstrate both gradualistic and punctuational evolutionary changes.« less

  5. Risk Evaluation of Railway Coal Transportation Network Based on Multi Level Grey Evaluation Model

    NASA Astrophysics Data System (ADS)

    Niu, Wei; Wang, Xifu

    2018-01-01

    The railway transport mode is currently the most important way of coal transportation, and now China’s railway coal transportation network has become increasingly perfect, but there is still insufficient capacity, some lines close to saturation and other issues. In this paper, the theory and method of risk assessment, analytic hierarchy process and multi-level gray evaluation model are applied to the risk evaluation of coal railway transportation network in China. Based on the example analysis of Shanxi railway coal transportation network, to improve the internal structure and the competitiveness of the market.

  6. Coaxial Lithography

    NASA Astrophysics Data System (ADS)

    Ozel, Tuncay

    The optical and electrical properties of heterogeneous nanowires are profoundly related to their composition and nanoscale architecture. However, the intrinsic constraints of conventional synthetic and lithographic techniques have limited the types of multi-compositional nanowires that can be realized and studied in the laboratory. This thesis focuses on bridging templated electrochemical synthesis and lithography for expanding current synthetic capabilities with respect to materials generality and the ability to tailor two-dimensional growth in the formation of core-shell structures for the rational design and preparation of nanowires with very complex architectures that cannot be made by any other techniques. Chapter 1 introduces plasmonics, templated electrochemical synthesis, and on-wire lithography concepts and their significances within chemistry and materials science. Chapter 2 details a powerful technique for the deposition of metals and semiconductors with nanometer resolution in segment and gap lengths using on-wire lithography, which serves as a new platform to explore plasmon-exciton interactions in the form of long-range optical nanoscale rulers. Chapter 3 highlights an approach for the electrochemical synthesis of solution dispersible core-shell polymeric and inorganic semiconductor nanowires with metallic leads. A photodetector based on a single core-shell semiconductor nanowire is presented to demonstrate the functionality of the nanowires produced using this approach. Chapter 4 describes a new materials general technique, termed coaxial lithography (COAL), bridging templated electrochemical synthesis and lithography for generating coaxial nanowires in a parallel fashion with sub-10 nanometer resolution in both axial and radial dimensions. Combinations of coaxial nanowires composed of metals, metal oxides, metal chalcogenides, conjugated polymers, and a core/shell semiconductor nanowire with an embedded plasmonic nanoring are presented to demonstrate the possibilities afforded by COAL. Chapter 5 addresses the use of COAL for the synthesis of solution dispersible metal nanorings and nanotubes with exceptional architectural tailorability of inner diameter, outer diameter, and length leading to precise spectral control over the resulting plasmonic fields ranging from visible to the near-IR. Chapter 6 is an outlook on templated electrochemical synthesis using coaxial lithography and highlights a few promising applications from nanoparticle assembly to light-matter interactions.

  7. New insights into enhanced anaerobic degradation of coal gasification wastewater (CGW) with the assistance of graphene.

    PubMed

    Zhu, Hao; Han, Yuxing; Ma, Wencheng; Han, Hongjun; Ma, Weiwei; Xu, Chunyan

    2018-08-01

    The up-flow anaerobic sludge blanket (UASB) system with graphene assisted was developed for coal gasification wastewater (CGW) treatment. Short-term results showed that optimal graphene addition (0.5 g/L) resulted in a more significant enhancement of methane production and chemical oxygen demand (COD) removal compared with that of the optimal activated carbon addition (10.0 g/L). Long-term results demonstrated that COD removal efficiency and methane production rate with graphene assisted achieved 64.7% and 180.5 mL/d, respectively. In addition, graphene could promote microbes accumulation and enzymes activity, resulting in higher extracellular polymeric substances (EPS) and coenzyme F 420 concentrations. X-ray Diffraction (XRD) analysis indicated that chemical of graphene changed insignificantly during the experiment. Meanwhile, with graphene assisted, cells were attached together to form microbial aggregates to facilitate sludge granulation process. Furthermore, the enriched Geobacter and Pseudomonas might perform direct interspecies electron transfer (DIET) with Methanosaeta via biological electrical connection, enhancing the anaerobic degradation of CGW. Copyright © 2018 Elsevier Ltd. All rights reserved.

  8. Ion Transport via Structural Relaxations in Polymerized Ionic Liquids

    NASA Astrophysics Data System (ADS)

    Ganesan, Venkat; Mogurampelly, Santosh

    We study the mechanisms underlying ion transport in poly(1-butyl-3-vinylimidazolium-hexafluorophosphate) polymer electrolytes. We consider polymer electrolytes of varying polymerized ionic liquid to ionic liquid (polyIL:IL) ratios and use atomistic molecular dynamics (MD) simulations to probe the dynamical and structural characteristics of the electrolyte. Our results reveal that anion diffusion along polymer backbone occurs primarily viathe formation and breaking of ion-pairs involving threepolymerized cationic monomers of twodifferent polymer chains. Moreover, we observe that the ionic diffusivities exhibit a direct correlation with the structural relaxation times of the ion-pairs and hydrogen bonds (H-bonds). These results provide new insights into the mechanisms underlying ion transport in polymerized ionic liquid electrolytes.

  9. Design and fabrication of advanced materials from Illinois coal wastes. Quarterly report, 1 March 1995--31 May 1995

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Malhotra, V.M.; Wright, M.A.

    1995-12-31

    The main goal of this project is to develop a bench-scale procedure to design and fabricate advanced brake and structural composite materials from Illinois coal combustion residues. Scanning electron microscopy (SEM), differential scanning calorimetry (DSC), differential thermal analysis (DTA), and transmission-Fourier transform infrared (FTIR) were conducted on PCC fly ash (Baldwin), FBC fly ash (ADM unit1-6), FBC fly ash (S.I. coal), FBC spent bed ash (ADM unit1-6), bottom ash, and scrubber sludge (CWLP) residues to characterize their geometrical shapes, mineral phases, and thermal stability. Our spectroscopic results indicate that the scrubber sludge is mainly composed of a gypsum-like phase whosemore » lattice structure is different from the lattice structure of conventional gypsum, and sludge does not contain hannebachite (CaSO{sub 3}0.5H{sub 2}O) phase. In the second and third quarters the focus of research has been on developing protocols for the formation of advanced brake composites and structural composites. Our attempts to fabricate brake frictional shoes, in the form of 1.25 inch disks, from PCC fly ash, FBC spent bed ash, scrubber sludge, coal char, iron particles, and coal tar were successful. Based on the experience gained and microscopic analyses, we have now upscaled our procedures to fabricate 2.5 inch diameter disks from coal combustion residues. The SEM and Young`s modulus analyses of brake composites fabricated at 400 psi < Pressure < 2200 psi suggest pressure has a strong influence on the particle packing and the filling of interstices in our composites.« less

  10. 30 CFR 778.22 - Facilities or structures used in common.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... INTERIOR SURFACE COAL MINING AND RECLAMATION OPERATIONS PERMITS AND COAL EXPLORATION SYSTEMS UNDER REGULATORY PROGRAMS PERMIT APPLICATIONS-MINIMUM REQUIREMENTS FOR LEGAL, FINANCIAL, COMPLIANCE, AND RELATED...

  11. Lipase-catalyzed ring-opening polymerization of lactones to polyesters and its mechanistic aspects.

    PubMed

    Namekawa, S; Suda, S; Uyama, H; Kobayashi, S

    1999-01-01

    Lipase catalysis induced a ring-opening polymerization of lactones with different ring-sizes. Small-size (four-membered) and medium-size lactones (six- and seven-membered) as well as macrolides (12-, 13-, 16-, and 17-membered) were subjected to lipase-catalyzed polymerization. The polymerization behaviors depended primarily on the lipase origin and the monomer structure. The macrolides showing much lower anionic polymerizability were enzymatically polymerized faster than epsilon-caprolactone. The granular immobilized lipase derived from Candida antartica showed extremely efficient catalysis in the polymerization of epsilon-caprolactone. Single-step terminal functionalization of the polyester was achieved by initiator and terminator methods. The enzymatic polymerizability of lactones was quantitatively evaluated by Michaelis-Menten kinetics.

  12. Energy and Resource-Saving Sources of Energy in Small Power Engineering of Siberia

    NASA Astrophysics Data System (ADS)

    Baranova, Marina

    2017-11-01

    The sustainable development of distant areas of Siberia is associated with the structures of energy demand and supply, the implementation and promotion of the process of environmentally safe restructuring of the energy supply system. It has been established that suspension coal fuels derived from brown coal, coal mining, coal processing wastes can be used as fuel. The results of experimental and industrial boilers on suspension water coal fuel are presented. The designs of vortex combustion chambers of various powers are developed and tested. The possibility of using coal-enrichment wastes and substandard coals for the production of manure-coal fuel briquettes was studied. It is shown that the strength and thermal power characteristics of briquettes depend on the moisture content and degree of metamorphism of the raw materials. The most effective percentage of the solid phase and manure, as a binder, was determined.

  13. Stress reduction in phase-separated, cross-linked networks: influence of phase structure and kinetics of reaction

    PubMed Central

    Szczepanski, Caroline R.; Stansbury, Jeffrey W.

    2014-01-01

    A mechanism for polymerization shrinkage and stress reduction was developed for heterogeneous networks formed via ambient, photo-initiated polymerization-induced phase separation (PIPS). The material system used consists of a bulk homopolymer matrix of triethylene glycol dimethacrylate (TEGDMA) modified with one of three non-reactive, linear prepolymers (poly-methyl, ethyl and butyl methacrylate). At higher prepolymer loading levels (10–20 wt%) an enhanced reduction in both shrinkage and polymerization stress is observed. The onset of gelation in these materials is delayed to a higher degree of methacrylate conversion (~15–25%), providing more time for phase structure evolution by thermodynamically driven monomer diffusion between immiscible phases prior to network macro-gelation. The resulting phase structure was probed by introducing a fluorescently tagged prepolymer into the matrix. The phase structure evolves from a dispersion of prepolymer at low loading levels to a fully co-continuous heterogeneous network at higher loadings. The bulk modulus in phase separated networks is equivalent or greater than that of poly(TEGDMA), despite a reduced polymerization rate and cross-link density in the prepolymer-rich domains. PMID:25418999

  14. Coal gasification systems engineering and analysis. Appendix H: Work breakdown structure

    NASA Technical Reports Server (NTRS)

    1980-01-01

    A work breakdown structure (WBS) is presented which encompasses the multiple facets (hardware, software, services, and other tasks) of the coal gasification program. The WBS is shown to provide the basis for the following: management and control; cost estimating; budgeting and reporting; scheduling activities; organizational structuring; specification tree generation; weight allocation and control; procurement and contracting activities; and serves as a tool for program evaluation.

  15. Poly-amido-saccharides: Synthesis via Anionic Polymerization of a β-Lactam Sugar Monomer

    PubMed Central

    Dane, Eric L.; Grinstaff, Mark W.

    2013-01-01

    Chiral poly-amido-saccharides (PASs) with a defined molecular weight and narrow polydispersity are synthesized using an anionic ring-opening polymerization of a β-lactam sugar monomer. The PASs have a previously unreported main chain structure that is composed of pyranose rings linked through the 1- and 2-positions by an amide bond with α-stereochemistry. The monomer is synthesized in one-step from benzyl-protected d-glucal and polymerized using mild reaction conditions to give degrees of polymerization ranging from 25 to >150 in high yield. Computational modeling reveals how the monomer’s structure and steric bulk affect the thermodynamics and kinetics of polymerization. Protected and deprotected polymers and model compounds are characterized using a variety of methods (NMR, GPC, IR, DLS, etc.). Reductive debenzylation provides the deprotected, hydrophilic polymers in high yield. Based on circular dichroism, the deprotected polymers possess a regular secondary structure in aqueous solution, which agrees favorably with the prediction of a helical structure using molecular modeling. Furthermore, we provide evidence suggesting that the polymers bind the lectin concanavalin A at the same site as natural carbohydrates, showing the potential of these polymers to mimic natural polysaccharides. PASs offer the advantages associated with synthetic polymers, such as greater control over structure and derivitization, and less batch-to-batch variation. At the same time, they preserve many of the structural features of natural polysaccharides, such as a stereochemically regular, rigid pyranose backbone, that make natural carbohydrate polymers important materials both for their unique properties and useful applications. PMID:22937875

  16. Fungal colonization and enzyme-mediated metabolism of waste coal by Neosartorya fischeri strain ECCN 84.

    PubMed

    Sekhohola, Lerato Mary; Isaacs, Michelle Louise; Cowan, Ashton Keith

    2014-01-01

    Colonization and oxidative metabolism of South African low-rank discard coal by the fungal strain ECCN 84 previously isolated from a coal environment and identified as Neosartorya fischeri was investigated. Results show that waste coal supported fungal growth. Colonization of waste coal particles by N. fischeri ECCN 84 was associated with the formation of compact spherical pellets or sclerotia-like structures. Dissection of the pellets from liquid cultures revealed a nucleus of "engulfed" coal which when analyzed by energy dispersive X-ray spectroscopy showed a time-dependent decline in weight percentage of elemental carbon and an increase in elemental oxygen. Proliferation of peroxisomes in hyphae attached to coal particles and increased extracellular laccase activity occurred after addition of waste coal to cultures of N. fischeri ECCN 84. These results support a role for oxidative enzyme action in the biodegradation of coal and suggest that extracellular laccase is a key component in this process.

  17. Interfacially polymerized layers for oxygen enrichment: a method to overcome Robeson's upper-bound limit.

    PubMed

    Tsai, Ching-Wei; Tsai, Chieh; Ruaan, Ruoh-Chyu; Hu, Chien-Chieh; Lee, Kueir-Rarn

    2013-06-26

    Interfacial polymerization of four aqueous phase monomers, diethylenetriamine (DETA), m-phenylenediamine (mPD), melamine (Mela), and piperazine (PIP), and two organic phase monomers, trimethyl chloride (TMC) and cyanuric chloride (CC), produce a thin-film composite membrane of polymerized polyamide layer capable of O2/N2 separation. To achieve maximum efficiency in gas permeance and O2/N2 permselectivity, the concentrations of monomers, time of interfacial polymerization, number of reactive groups in monomers, and the structure of monomers need to be optimized. By controlling the aqueous/organic monomer ratio between 1.9 and 2.7, we were able to obtain a uniformly interfacial polymerized layer. To achieve a highly cross-linked layer, three reactive groups in both the aqueous and organic phase monomers are required; however, if the monomers were arranged in a planar structure, the likelihood of structural defects also increased. On the contrary, linear polymers are less likely to result in structural defects, and can also produce polymer layers with moderate O2/N2 selectivity. To minimize structural defects while maximizing O2/N2 selectivity, the planar monomer, TMC, containing 3 reactive groups, was reacted with the semirigid monomer, PIP, containing 2 reactive groups to produce a membrane with an adequate gas permeance of 7.72 × 10(-6) cm(3) (STP) s(-1) cm(-2) cm Hg(-1) and a high O2/N2 selectivity of 10.43, allowing us to exceed the upper-bound limit of conventional thin-film composite membranes.

  18. A Combined Micro-CT Imaging/Microfluidic Approach for Understating Methane Recovery in Coal Seam Gas Reservoirs

    NASA Astrophysics Data System (ADS)

    Mostaghimi, P.; Armstrong, R. T.; Gerami, A.; Lamei Ramandi, H.; Ebrahimi Warkiani, M.

    2015-12-01

    Coal seam methane is a form of natural gas stored in coal beds and is one of the most important unconventional resources of energy. The flow and transport in coal beds occur in a well-developed system of natural fractures that are also known as cleats. We use micro-Computed Tomography (CT) imaging at both dry and wet conditions to resolve the cleats below the resolution of the image. Scanning Electron Microscopy (SEM) is used for calibration of micro-CT data. Using soft lithography technique, the cleat system is duplicated on a silicon mould. We fabricate a microfluidic chip using Polydimethylsiloxane (PDMS) to study both imbibition and drainage in generated coal structures for understating gas and water transport in coal seam reservoirs. First, we use simple patterns observed on coal images to analyse the effects of wettability, cleat size and distribution on flow behaviour. Then, we study transport in a coal by injecting both distilled water and decane with a rate of 1 microliter/ min into the fabricated cleat structure (Figure 1), initially saturated with air. We repeat the experiment for different contact angles by plasma treating the microfluidic chip, and results show significant effects of wettability on the displacement efficiency. The breakthrough time in the imbibition setup is significantly longer than in the drainage. Using rapid video capturing, and high resolution microscopy, we measure the saturation of displacing fluid with respect to time. By measuring gas and liquid recovery in the outlet at different saturation, we predict relative permeability of coal. This work has important applications for optimising gas recovery and our results can serve as a benchmark in the verification of multiphase numerical models used in coal seam gas industry.

  19. Engineering and Design: Composite Materials for Civil Engineering Structures

    DTIC Science & Technology

    1997-03-31

    the effects of acidic, salt, and fresh waters . Acidic, salt, and fresh waters are corrosive to ferrous metals. In Corps of Engineers structures, high...what is commonly called a toughened epoxy. (5) Polymeric resins will absorb moisture. Since many applications are in contact with water (at least...ultraviolet radiation. Some coatings can reduce the amount of moisture absorption by the structure. All polymeric resins will absorb water to some

  20. Functional, photochemically active, and chemically asymmetric membranes by interfacial polymerization of derivatized multifunctional prepolymers

    DOEpatents

    Lonsdale, H.K.; Wamser, C.C.

    1990-04-17

    The preparation of a novel class of thin film membranes by interfacial polymerization is disclosed, said membranes incorporating as part of their polymeric structure the functionality of monomeric or oligomeric precursors. Specific embodiments include porphyrin and phthalocyanine derivatives that are photochemically or electrochemically active, as well as chemically asymmetric membranes.

  1. Functional, photochemically active, and chemically asymmetric membranes by interfacial polymerization of derivatized multifunctional prepolymers

    DOEpatents

    Lonsdale, Harold K.; Wamser, Carl C.

    1990-01-01

    The preparation of a novel class of thin film membranes by interfacial polymerization is disclosed, said membranes incorporating as part of their polymeric structure the functionality of monomeric or oligomeric precursors. Specific embodiments include porphyrin and phthalocyanine derivatives that are photochemically or electrochemically active, as well as chemically asymmetric membranes.

  2. Functional, photochemically active, and chemically asymmetric membranes by interfacial polymerization of derivatized multifunctional prepolymers

    DOEpatents

    Lonsdale, Harold K.; Wamser, Carl C.

    1988-01-01

    The preparation of a novel class of thin film membranes by interfacial polymerization is disclosed, said membanes incorporating as part of their polymeric structure the functionality of monomeric or oligomeric precursors. Specific embodiments include porphyrin and phthalocyanime derivatives that are photochemically or electrochemically active, as well as chemically asymmetric membranes.

  3. The impact of the structural features of the rock mass on seismicity in Polish coal mines

    NASA Astrophysics Data System (ADS)

    Patyńska, Renata

    2017-11-01

    The article presents seismic activity induced in the coal mines of the Upper Silesian Coal Basin (GZW) in relation to the locations of the occurrence of rockbursts. The comparison of these measurements with the structural features of the rock mass of coal mines indicates the possibility of estimating the so-called Unitary Energy Expenditure (UEE) in a specific time. The obtained values of UEE were compared with the distribution of seismic activity in GZW mines. The level of seismic activity in the analysed period changed and depended on the intensity of mining works and diverse mining and geological conditions. Five regions, where tremors occurred (Bytom Trough, Main Saddle, Main Trough, Kazimierz Trough, and Jejkowice and Chwałowice Trough) which belong to various structural units of the Upper Silesia were analyzed. It was found out that rock bursts were recorded only in three regions: Main Saddle, Bytom Trough, and Jejkowice and Chwałowice Trough.

  4. Metastable Polymeric Nitrogen: The Ultimate Green High-Energy-Density Material

    NASA Astrophysics Data System (ADS)

    Ciezak, Jennifer

    2007-06-01

    High-energy-high-density materials offering increased stability, vulnerability, and environmental safety are being aggressively pursued to meet the requirements of the DoD Joint Visions and Future Force. Nearly two decades ago, it was proposed that polymeric nitrogen would exceed all of these requirements and possess nearly five times the energy of any conventional energetic material in use today. The present study details an investigation into nitrogen polymerization using a novel high-pressure approach utilizing sodium azide as the starting material. Due to the weaker bonding structure of the anionic azide chains in comparison to a N-N triple bond, one expects that the azide chains will create single-covalently bonded polymeric networks more easily than diatomic nitrogen. A polymeric form of sodium azide was synthesized at high pressures, but the material was not metastable at ambient conditions, which precluded performance testing. Quantum chemical calculations have indicated stabilization of the polymeric structure at ambient conditions may be possible with the addition of hydrogen. Vibrational spectroscopic characterization suggests that a meta-stable polymeric form of nitrogen has been synthesized under high-pressure using sodium azide/hydrogen as the starting materials. This material remains stable at ambient conditions upwards of two weeks depending on the storage conditions.

  5. Chlorine in coal and its relationship with boiler corrosion. Technical report, 1 March--31 May 1994

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chou, M.I.M.; Lytle, J.M.; Ruch, R.R.

    1994-09-01

    Limited literature and use history data have suggested that some high-chlorine Illinois coals do not cause boiler corrosion while extensive data developed by the British correlate corrosion with chlorine content and other parameters related to the coal and boiler. The differences in corrosivity in coals may be due to the coal properties, to blending of coals, or to the boiler parameters in which they were burned. The goals of this study focus on coal properties. In this quarter, both destructive temperature-programmed Thermogravimetry with Fourier transform infrared (TGA-FTIR) and non-destructive X-ray absorption near-edge structure (XANES) techniques were used to examine themore » forms and the evolution characteristics of chlorine in coals. The TGA-FTIR results indicate that under oxidation condition, both British and Illinois coals release hydrogen chloride gas. Illinois coals release the gas at high temperature with maximum evolution temperature ranged between 210 and 280 C. The XANES results indicate that chlorine in coal exists in ionic forms including a solid salt form. The solid NaCl salt form, however, is observed only in some of the British coals and none of the Illinois coals. These results combined with TGA-FTIR results suggest that the chlorine ions in Illinois coals are different from the chlorine ions in British coals.« less

  6. Polymeric peptide pigments with sequence-encoded properties

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lampel, Ayala; McPhee, Scott A.; Park, Hang-Ah

    Melanins are a family of heterogeneous polymeric pigments that provide ultraviolet (UV) light protection, structural support, coloration, and free radical scavenging. Formed by oxidative oligomerization of catecholic small molecules, the physical properties of melanins are influenced by covalent and noncovalent disorder. We report the use of tyrosine-containing tripeptides as tunable precursors for polymeric pigments. In these structures, phenols are presented in a (supra-)molecular context dictated by the positions of the amino acids in the peptide sequence. Oxidative polymerization can be tuned in a sequence-dependent manner, resulting in peptide sequence–encoded properties such as UV absorbance, morphology, coloration, and electrochemical properties overmore » a considerable range. Short peptides have low barriers to application and can be easily scaled, suggesting near-term applications in cosmetics and biomedicine.« less

  7. Covalently bonded networks through surface-confined polymerization

    NASA Astrophysics Data System (ADS)

    El Garah, Mohamed; MacLeod, Jennifer M.; Rosei, Federico

    2013-07-01

    The prospect of synthesizing ordered, covalently bonded structures directly on a surface has recently attracted considerable attention due to its fundamental interest and for potential applications in electronics and photonics. This prospective article focuses on efforts to synthesize and characterize epitaxial one- and two-dimensional (1D and 2D, respectively) polymeric networks on single crystal surfaces. Recent studies, mostly performed using scanning tunneling microscopy (STM), demonstrate the ability to induce polymerization based on Ullmann coupling, thermal dehalogenation and dehydration reactions. The 2D polymer networks synthesized to date have exhibited structural limitations and have been shown to form only small domains on the surface. We discuss different approaches to control 1D and 2D polymerization, with particular emphasis on the surface phenomena that are critical to the formation of larger ordered domains.

  8. Polymeric hydrogels for novel contact lens-based ophthalmic drug delivery systems: a review.

    PubMed

    Xinming, Li; Yingde, Cui; Lloyd, Andrew W; Mikhalovsky, Sergey V; Sandeman, Susan R; Howel, Carol A; Liewen, Liao

    2008-04-01

    Only about 5% of drugs administrated by eye drops are bioavailable, and currently eye drops account for more than 90% of all ophthalmic formulations. The bioavailability of ophthalmic drugs can be improved by a soft contact lens-based ophthalmic drug delivery system. Several polymeric hydrogels have been investigated for soft contact lens-based ophthalmic drug delivery systems: (i) polymeric hydrogels for conventional contact lens to absorb and release ophthalmic drugs; (ii) polymeric hydrogels for piggyback contact lens combining with a drug plate or drug solution; (iii) surface-modified polymeric hydrogels to immobilize drugs on the surface of contact lenses; (iv) polymeric hydrogels for inclusion of drugs in a colloidal structure dispersed in the lens; (v) ion ligand-containing polymeric hydrogels; (vi) molecularly imprinted polymeric hydrogels which provide the contact lens with a high affinity and selectivity for a given drug. Polymeric hydrogels for these contact lens-based ophthalmic drug delivery systems, their advantages and drawbacks are critically analyzed in this review.

  9. Self-assembly of block copolymers on topographically patterned polymeric substrates

    DOEpatents

    Russell, Thomas P.; Park, Soojin; Lee, Dong Hyun; Xu, Ting

    2016-05-10

    Highly-ordered block copolymer films are prepared by a method that includes forming a polymeric replica of a topographically patterned crystalline surface, forming a block copolymer film on the topographically patterned surface of the polymeric replica, and annealing the block copolymer film. The resulting structures can be used in a variety of different applications, including the fabrication of high density data storage media. The ability to use flexible polymers to form the polymeric replica facilitates industrial-scale processes utilizing the highly-ordered block copolymer films.

  10. Pyrolysis kinetics of coking coal mixed with biomass under non-isothermal and isothermal conditions.

    PubMed

    Jeong, Ha Myung; Seo, Myung Won; Jeong, Sang Mun; Na, Byung Ki; Yoon, Sang Jun; Lee, Jae Goo; Lee, Woon Jae

    2014-03-01

    To investigate the kinetic characteristics of coking coal mixed with biomass during pyrolysis, thermogravimetric (TG) and thermo-balance reactor (TBR) analyses were conducted under non-isothermal and isothermal condition. Yellow poplar as a biomass (B) was mixed with weak coking coal (WC) and hard coking coal (HC), respectively. The calculated activation energies of WC/B blends were higher than those of HC/B blends under non-isothermal and isothermal conditions. The coal/biomass blends show increased reactivity and decreased activation energy with increasing biomass blend ratio, regardless of the coking properties of the coal. The different char structures of the WC/B and HC/B blends were analyzed by BET and SEM. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. Modes of occurrence of mercury and other trace elements in coals from the warrior field, Black Warrior Basin, Northwestern Alabama

    USGS Publications Warehouse

    Diehl, S.F.; Goldhaber, M.B.; Hatch, J.R.

    2004-01-01

    The mineralogic residence and abundance of trace metals is an important environmental issue. Data from the USGS coal quality database show that potentially toxic elements, including Hg, As, Mo, Se, Cu, and Tl are enriched in a subset of coal samples in the Black Warrior Basin of Alabama, USA. Although the coal as-mined typically is low in these elements, localized enrichments occur in high-pyrite coals and near faults. Microscopic analyses demonstrate that the residence of these elements is dominantly in a late-stage pyrite associated with structurally disrupted coal. Further, our data suggest addition of Hg to the coal matrix as well. The source of these trace elements was hydrothermal fluids driven into the Black Warrior Basin by Alleghanian age tectonism. ?? 2004 Published by Elsevier B.V.

  12. Structural and functional characteristics of natural and constructed channels draining a reclaimed mountaintop removal and valley fill coal mine

    EPA Science Inventory

    Mountaintop removal and valley fill (MTR/VF) coal mining has altered the landscape of the Central Appalachian region in the United States. The goals of this study were to 1) compare the structure and function of natural and constructed stream channels in forested and MTR/VF catch...

  13. Cyclic terpenoids of contemporary resinous plant detritus and of fossil woods, ambers and coals

    USGS Publications Warehouse

    Simoneit, B.R.T.; Grimalt, J.O.; Wang, T.-G.; Cox, R.E.; Hatcher, P.G.; Nissenbaum, A.

    1986-01-01

    Cyclic terpenoids present in the solvent extractable material of fossil woods, ambers and brown coals have been analyzed. The sample series chosen consisted of wood remains preserved in Holocene to Jurassic sediments and a set of of ambers from the Philippines (copalite), Israel, Canada and Dominican Republic. The brown coals selected were from the Fortuna Garsdorf Mine and Miocene formations on Fiji. The fossil wood extracts contained dominant diterpenoid or sesquiterpenoid skeletons, and aromatized species were present at high concentrations, with a major amount of two-ring aromatic compounds. Tricyclic diterpenoids were the predominant compounds in the ambers. Aromatized derivatives were the major components, consisting of one or two aromatic ring species with the abietane and occasionally pimarane skeletons. The saturated structures were comprised primarily of the abietane and pimarane skeletons having from three to five carbon (C1, C2, etc.) substituents. Kaurane and phyllocladane isomers were present in only minor amounts. Bicyclic sesquiterpenoids as saturated and partial or fully aromatized forms were also common in these samples, but only traces of sesterterpenoids and triterpenoid derivatives were found. The brown coal extracts were composed of major amounts of one- and two-ring aromatized terpenoids, with a greater proportion of triterpenoid derivatives than in the case of the woods and ambers. This was especially noticeable for the German coal, where the triterpenoids were predominant. Open C-ring aromatized structures were also present in this coal. Steroid compounds were not detectable, but some hopanes were found as minor components in the German brown coal. An overview of the skeletal structure classes identified in each sample, as well as the general mass spectrometric characteristics of the unknown compounds are included in the present paper. It can be concluded from these structural distributions that aromatization is the main process for the transformation of terrestrial cyclic terpenoids during diagenesis, constituting a general pathway for all terpenoids. ?? 1986 Pergamon Journals Ltd.

  14. Imidazoline and imidazolidine nitroxides as controlling agents in nitroxide-mediated pseudoliving radical polymerization

    NASA Astrophysics Data System (ADS)

    Edeleva, M. V.; Marque, S. R. A.; Bagryanskaya, E. G.

    2018-04-01

    Controlled, or pseudoliving, radical polymerization provides unique opportunities for the synthesis of structurally diverse polymers with a narrow molecular-weight distribution. These reactions occur under relatively mild conditions with broad tolerance to functional groups in the monomers. The nitroxide-mediated pseudoliving radical polymerization is of particular interest for the synthesis of polymers for biomedical applications. This review briefly describes one of the mechanisms of controlled radical polymerization. The studies dealing with the use of imidazoline and imidazolidine nitroxides as controlling agents for nitroxide-mediated pseudoliving radical polymerization of various monomers are summarized and analyzed. The publications addressing the key steps of the controlled radical polymerization in the presence of imidazoline and imidazolidine nitroxides and new approaches to nitroxide-mediated polymerization based on protonation of both nitroxides and monomers are considered. The bibliography includes 154 references.

  15. Relationship between enhanced dewaterability and structural properties of hydrothermal sludge after hydrothermal treatment of excess sludge.

    PubMed

    Wang, Liping; Li, Aimin; Chang, Yuzhi

    2017-04-01

    Hydrothermal treatment is an effective method to enhance the deep dewaterability of excess sludge with low energy consumption. In this study, an insight into the relationship between enhanced dewaterability and structural properties of the produced hydrothermal sludge was presented, aiming at better understanding the effect of hydrothermal process on excess sludge dewatering performance. The results indicated that hydrothermal effect induced the transformation of surface water to interstitial and free water by lowering the binding strength between adjacent water and solid particles and that free water became the main form for moisture existence in hydrothermal sludge as temperature was higher than 180 °C. Increase in temperature of hydrothermal treatment generated a significant size reduction of sludge flocs but treated sludge with a higher rigidity, which not only strengthened the network of hydrothermal sludge but also destroyed the binding of EPS with water. Hydrothermal process caused crevice and pore structures of excess sludge to disappear gradually, which was a main driving force of water removal as temperature was below 150 °C. With the temperature of hydrothermal treatment exceeding 180 °C, the morphology of hydrothermal sludge became rough which linked closely to the solid precipitation of condensation polymerization, and further became smooth at higher temperature (210 °C) due to the coal-like structures with higher aromaticities, indicating that hydrothermal reaction pathways began to play a main role in enhanced dewaterability. Hydrothermal treatment led to more alkyl and aromatic carbon, but lower O-alkyl, carboxyl and carbonyl carbon. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Particle-filled microporous materials

    DOEpatents

    McAllister, Jerome W.; Kinzer, Kevin E.; Mrozinski, James S.; Johnson, Eric J.; Dyrud, James F.

    1990-01-01

    A microporous particulate-filled thermoplastic polymeric article is provided. The article can be in the form of a film, a fiber, or a tube. The article has a thermoplastic polymeric structure having a plurality of interconnected passageways to provide a network of communicating pores. The microporous structure contains discrete submicron or low micron-sized particulate filler, the particulate filler being substantially non-agglomerated.

  17. Particle-filled microporous materials

    DOEpatents

    McAllister, Jerome W.; Kinzer, Kevin E.; Mrozinski, James S.; Johnson, Eric J.

    1992-07-14

    A microporous particulate-filled thermoplastic polymeric article is provided. The article can be in the form of a film, a fiber, or a tube. The article has a thermoplastic polymeric structure having a plurality of interconnected passageways to provide a network of communicating pores. The microporous structure contains discrete submicron or low micron-sized particulate filler, the particulate filler being substantially non-agglomerated.

  18. Atomic-resolution structure of the CAP-Gly domain of dynactin on polymeric microtubules determined by magic angle spinning NMR spectroscopy.

    PubMed

    Yan, Si; Guo, Changmiao; Hou, Guangjin; Zhang, Huilan; Lu, Xingyu; Williams, John Charles; Polenova, Tatyana

    2015-11-24

    Microtubules and their associated proteins perform a broad array of essential physiological functions, including mitosis, polarization and differentiation, cell migration, and vesicle and organelle transport. As such, they have been extensively studied at multiple levels of resolution (e.g., from structural biology to cell biology). Despite these efforts, there remain significant gaps in our knowledge concerning how microtubule-binding proteins bind to microtubules, how dynamics connect different conformational states, and how these interactions and dynamics affect cellular processes. Structures of microtubule-associated proteins assembled on polymeric microtubules are not known at atomic resolution. Here, we report a structure of the cytoskeleton-associated protein glycine-rich (CAP-Gly) domain of dynactin motor on polymeric microtubules, solved by magic angle spinning NMR spectroscopy. We present the intermolecular interface of CAP-Gly with microtubules, derived by recording direct dipolar contacts between CAP-Gly and tubulin using double rotational echo double resonance (dREDOR)-filtered experiments. Our results indicate that the structure adopted by CAP-Gly varies, particularly around its loop regions, permitting its interaction with multiple binding partners and with the microtubules. To our knowledge, this study reports the first atomic-resolution structure of a microtubule-associated protein on polymeric microtubules. Our approach lays the foundation for atomic-resolution structural analysis of other microtubule-associated motors.

  19. Molecular accessibility in solvent swelled coal

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kispert, L.D.

    1991-08-01

    Research continued on the determination of pore size and number distribution changes after swelling the coal samples with various solvents. A paper has just been submitted to the journal Fuel on the Low temperature Swelling of Argonne Premium Coal samples using solvents of varying polarity. The variation in the shape of the pore was followed as a function of temperature and swelling solvent polarity. This change in pore structure was attributed to break-up of the hydrogen bonding network in coal by polar solvents. The modification in pore shape from spherical to cylindrical was attributed to anisotropy in hydrogen bond densities.more » A copy of this paper has been attached to this report. Wojciech Sady has determine the structural changes in the pores that occur when APCS coal is dehydrated prior to swelling with polar solvents. These changes are different from those that occur in the absence of prior dehydration. He has also completed a study on the variation in the hydrogen bonding character of the pore wall as the coals are swelled with various polar solvents. A statistical analysis of the data is currently underway to determine important trends in his data. 9 refs.« less

  20. Roles of N-glycans in the polymerization-dependent aggregation of mutant Ig-μ chains in the early secretory pathway.

    PubMed

    Giannone, Chiara; Fagioli, Claudio; Valetti, Caterina; Sitia, Roberto; Anelli, Tiziana

    2017-02-03

    The polymeric structure of secretory IgM allows efficient antigen binding and complement fixation. The available structural models place the N-glycans bound to asparagines 402 and 563 of Ig-μ chains within a densely packed core of native IgM. These glycans are found in the high mannose state also in secreted IgM, suggesting that polymerization hinders them to Golgi processing enzymes. Their absence alters polymerization. Here we investigate their role following the fate of aggregation-prone mutant μ chains lacking the Cμ1 domain (μ∆). Our data reveal that μ∆ lacking 563 glycans (μ∆5) form larger intracellular aggregates than μ∆ and are not secreted. Like μ∆, they sequester ERGIC-53, a lectin previously shown to promote polymerization. In contrast, μ∆ lacking 402 glycans (μ∆4) remain detergent soluble and accumulate in the ER, as does a double mutant devoid of both (μ∆4-5). These results suggest that the two C-terminal Ig-μ glycans shape the polymerization-dependent aggregation by engaging lectins and acting as spacers in the alignment of individual IgM subunits in native polymers.

  1. Roles of N-glycans in the polymerization-dependent aggregation of mutant Ig-μ chains in the early secretory pathway

    PubMed Central

    Giannone, Chiara; Fagioli, Claudio; Valetti, Caterina; Sitia, Roberto; Anelli, Tiziana

    2017-01-01

    The polymeric structure of secretory IgM allows efficient antigen binding and complement fixation. The available structural models place the N-glycans bound to asparagines 402 and 563 of Ig-μ chains within a densely packed core of native IgM. These glycans are found in the high mannose state also in secreted IgM, suggesting that polymerization hinders them to Golgi processing enzymes. Their absence alters polymerization. Here we investigate their role following the fate of aggregation-prone mutant μ chains lacking the Cμ1 domain (μ∆). Our data reveal that μ∆ lacking 563 glycans (μ∆5) form larger intracellular aggregates than μ∆ and are not secreted. Like μ∆, they sequester ERGIC-53, a lectin previously shown to promote polymerization. In contrast, μ∆ lacking 402 glycans (μ∆4) remain detergent soluble and accumulate in the ER, as does a double mutant devoid of both (μ∆4–5). These results suggest that the two C-terminal Ig-μ glycans shape the polymerization-dependent aggregation by engaging lectins and acting as spacers in the alignment of individual IgM subunits in native polymers. PMID:28157181

  2. Geological and geochemical characteristics of high arsenic coals from endemic arsenosis areas in southwestern Guizhou Province, China

    USGS Publications Warehouse

    Ding, Z.; Zheng, B.; Long, J.; Belkin, H.E.; Finkelman, R.B.; Chen, C.; Zhou, D.; Zhou, Y.

    2001-01-01

    Southwest Guizhou Province is one of the most important areas of disseminated, sediment-hosted-type Au deposits in China and is an important area of coal production. The chemistry of most of the coals in SW Guizhou is similar to those in other parts of China. Their As content is near the Chinese coal average, but some local, small coal mines contain high As coals. The highest As content is up to 3.5 wt.% in the coal. The use of high As coals has caused in excess of 3000 cases of As poisoning in several villages. The high As coals are in the Longtan formation, which is an alternating marine facies and terrestrial facies. The coals are distributed on both sides of faults that parallel the regional anticlinal axis. The As content of coal is higher closer to the fault plane. The As content of coal changes greatly in different coal beds and different locations of the same bed. Geological structures such as anticlines, faults and sedimentary strata control the distribution of high As coals. Small Au deposits as well as Sb, Hg, and Th mineralization, are found near the high As coals. Although some As-bearing minerals such as pyrite, arsenopyrite, realgar (?), As-bearing sulfate, As-bearing clays, and phosphate are found in the high As coals, their contents cannot account for the abundance of As in some coals. Analysis of the coal indicates that As mainly exists in the form of As5+ and As3+, perhaps, combined with organic compounds. The occurrence of such exceptionally high As contents in coal and the fact that the As is dominantly organically associated are unique observations. ?? 201 Elsevier Science Ltd.

  3. Rosebud SynCoal Partnership, SynCoal{reg_sign} demonstration technology update

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sheldon, R.W.

    1997-12-31

    An Advanced Coal Conversion Process (ACCP) technology being demonstrated in eastern Montana (USA) at the heart of one of the world`s largest coal deposits is providing evidence that the molecular structure of low-rank coals can be altered successfully to produce a unique product for a variety of utility and industrial applications. The product is called SynCoal{reg_sign} and the process has been developed by the Rosebud SynCoal Partnership (RSCP) through the US Department of Energy`s multi-million dollar Clean Coal Technology Program. The ACCP demonstration process uses low-pressure, superheated gases to process coal in vibrating fluidized beds. Two vibratory fluidized processing stagesmore » are used to heat and convert the coal. This is followed by a water spray quench and a vibratory fluidized stage to cool the coal. Pneumatic separators remove the solid impurities from the dried coal. There are three major steps to the SynCoal{reg_sign} process: (1) thermal treatment of the coal in an inert atmosphere, (2) inert gas cooling of the hot coal, and (3) removal of ash minerals. When operated continuously, the demonstration plant produces over 1,000 tons per day (up to 300,000 tons per year) of SynCoal{reg_sign} with a 2% moisture content, approximately 11,800b Btu/lb and less than 1.0 pound of SO{sub 2} per million Btu. This product is obtained from Rosebud Mine sub-bituminous coal which starts with 25% moisture, 8,600 Btu/lb and approximately 1.6 pounds of SO{sub 2} per million Btu.« less

  4. Ground Penetrating Radar, a Method for Exploration and Monitoring of Coal Fires in China

    NASA Astrophysics Data System (ADS)

    Gundelach, Volker

    2010-05-01

    Due to the climate change it is a global task to fight against gas emission of coal fires. In China exists many burning coal seams which should be extinguished. A Chinese-German initiative tries to find new technologies and solutions to control these fires. Most of the fires are close to the surface in arid areas. In that case GPR is a possible geophysical method to get detailed information about the structure of the soil. Mining activities and the burning coal are leaving voids which collapse or still exist as dangerous areas. With GPR it is possible to detect voids and clefts. Crevices are potential paths for oxygen transport from the surface to the fire. The knowledge of these structures would help to extinguish the fire. The heat of the burning coal changes the permittivity and the conductivity of the rock. This affects the radar signal and makes it possible to separate burning zones from intact zones. Monitoring of the burning zones helps to find optimal solutions for fire extinguishing strategies. Several field campaigns were made in China. One campaign was in the province Xinjiang with a 50 MHz system from Mala on a steep dipping coal seam. Other campaigns were in the Inner Mongolia with 40 MHz to 200 MHz antennae from GSSI on shallow dipping coal seams. The experiences from these measurements will be shown. The surveys were collected in rough terrain. The data from the unshielded antennae contained a lot of effects coming through the air. The limits of detecting crevices with GPR will be demonstrated. Some parts of the measurements over burning coal were influenced by strong anomalies of the magnetization. Modeling of the radar signal helps at the interpretation. Parts of the interpretation from the surveys can be validated by the outcrop of the investigated structures. A spatial visualization of the results is the basis for discussions.

  5. Deformation Failure Characteristics of Coal Body and Mining Induced Stress Evolution Law

    PubMed Central

    Wen, Zhijie; Wen, Jinhao; Shi, Yongkui; Jia, Chuanyang

    2014-01-01

    The results of the interaction between coal failure and mining pressure field evolution during mining are presented. Not only the mechanical model of stope and its relative structure division, but also the failure and behavior characteristic of coal body under different mining stages are built and demonstrated. Namely, the breaking arch and stress arch which influence the mining area are quantified calculated. A systematic method of stress field distribution is worked out. All this indicates that the pore distribution of coal body with different compressed volume has fractal character; it appears to be the linear relationship between propagation range of internal stress field and compressed volume of coal body and nonlinear relationship between the range of outburst coal mass and the number of pores which is influenced by mining pressure. The results provide theory reference for the research on the range of mining-induced stress and broken coal wall. PMID:24967438

  6. Adaptive optimization as a design and management methodology for coal-mining enterprise in uncertain and volatile market environment - the conceptual framework

    NASA Astrophysics Data System (ADS)

    Mikhalchenko, V. V.; Rubanik, Yu T.

    2016-10-01

    The work is devoted to the problem of cost-effective adaptation of coal mines to the volatile and uncertain market conditions. Conceptually it can be achieved through alignment of the dynamic characteristics of the coal mining system and power spectrum of market demand for coal product. In practical terms, this ensures the viability and competitiveness of coal mines. Transformation of dynamic characteristics is to be done by changing the structure of production system as well as corporate, logistics and management processes. The proposed methods and algorithms of control are aimed at the development of the theoretical foundations of adaptive optimization as basic methodology for coal mine enterprise management in conditions of high variability and uncertainty of economic and natural environment. Implementation of the proposed methodology requires a revision of the basic principles of open coal mining enterprises design.

  7. Research on Improving Low Rank Coal Caking Ability by Moderate Hydrogenation

    NASA Astrophysics Data System (ADS)

    Huang, Peng

    2017-12-01

    The hydrogenation test of low metamorphic coal was carried out by using a continuous hydrogen reactor at the temperature of (350-400)°C and the initial hydrogen pressure of 3 ~ 6Mpa. The purpose of the experiment was to increase the caking property, and the heating time was controlled from 30 to 50min. The test results show that the mild hydrogenation test, no adhesion of low metamorphic coal can be transformed into a product having adhesion, oxygen elements in coal have good removal, the calorific value of the product has been improved significantly and coal particles during pyrolysis, swelling, catalyst, hydrogenation, structural changes and the combined effects of particles a new component formed between financial and is a major cause of coal caking enhancement and lithofacies change, coal blending test showed that the product can be used effectively in the coking industry.

  8. Development of Methods of Characterizing Coal in Its Plastic State

    NASA Technical Reports Server (NTRS)

    Lloyd, W. G.

    1978-01-01

    Coal in its plastic state (typically 400-460 C) was examined by the isothermal Gieseler plastometry of seven selected coals of widely varying plastic properties. Kinetic models were proposed for the isothermal plastometric curves. Plastic behavior was compared with a variety of laboratory analyses and characterizations of these coals, including classical coal analysis; mineral analysis; microstructural analysis (extractable fractions, surface area measurement, and petrographic analysis); and thermal analysis (thermogravimetric analysis, thermomechanical analysis, and differential scanning calorimetry). The phenomenon of a sharp, large, poorly reproducible exotherm in the differential scanning calorimetric analysis of coking coals was examined. Several coal extrudates show mineral distribution, organic maceral composition and overall calorific value to be little affected by 800 F extrusion. Volatile matter and plastic properties are moderately reduced, and the network structure (as gauged by extractables) appears to be slightly degraded in the extrusion process.

  9. Prevention of trace and major element leaching from coal combustion products by hydrothermally-treated coal ash

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Adnadjevic, B.; Popovic, A.; Mikasinovic, B.

    2009-07-01

    The most important structural components of coal ash obtained by coal combustion in 'Nikola Tesla A' power plant located near Belgrade (Serbia) are amorphous alumosilicate, alpha-quartz, and mullite. The phase composition of coal ash can be altered to obtain zeolite type NaA that crystallizes in a narrow crystallization field (SiO{sub 2}/Al{sub 2}O{sub 3}; Na{sub 2}O/SiO{sub 2}; H{sub 2}O/Na{sub 2}O ratios). Basic properties (crystallization degree, chemical composition, the energy of activation) of obtained zeolites were established. Coal ash extracts treated with obtained ion-exchange material showed that zeolites obtained from coal ash were able to reduce the amounts of iron, chromium, nickel,more » zinc, copper, lead, and manganese in ash extracts, thus proving its potential in preventing pollution from dump effluent waters.« less

  10. Geologic Map of Upper Cretaceous and Tertiary Strata and Coal Stratigraphy of the Paleocene Fort Union Formation, Rawlins-Little Snake River Area, South-Central Wyoming

    USGS Publications Warehouse

    Hettinger, R.D.; Honey, J.G.; Ellis, M.S.; Barclay, C.S.V.; East, J.A.

    2008-01-01

    This report provides a map and detailed descriptions of geologic formations for a 1,250 square mile region in the Rawlins-Little Snake River coal field in the eastern part of the Washakie and Great Divide Basins of south-central Wyoming. Mapping of geologic formations and coal beds was conducted at a scale of 1:24,000 and compiled at a scale of 1:100,000. Emphasis was placed on coal-bearing strata of the China Butte and Overland Members of the Paleocene Fort Union Formation. Surface stratigraphic sections were measured and described and well logs were examined to determine the lateral continuity of individual coal beds; the coal-bed stratigraphy is shown on correlation diagrams. A structure contour and overburden map constructed on the uppermost coal bed in the China Butte Member is also provided.

  11. Polymeric Biomaterials: Diverse Functions Enabled by Advances in Macromolecular Chemistry

    PubMed Central

    Liang, Yingkai; Li, Linqing; Scott, Rebecca A.; Kiick, Kristi L.

    2017-01-01

    Biomaterials have been extensively used to leverage beneficial outcomes in various therapeutic applications, such as providing spatial and temporal control over the release of therapeutic agents in drug delivery as well as engineering functional tissues and promoting the healing process in tissue engineering and regenerative medicine. This perspective presents important milestones in the development of polymeric biomaterials with defined structures and properties. Contemporary studies of biomaterial design have been reviewed with focus on constructing materials with controlled structure, dynamic functionality, and biological complexity. Examples of these polymeric biomaterials enabled by advanced synthetic methodologies, dynamic chemistry/assembly strategies, and modulated cell-material interactions have been highlighted. As the field of polymeric biomaterials continues to evolve with increased sophistication, current challenges and future directions for the design and translation of these materials are also summarized. PMID:29151616

  12. Thermodynamic Presynthetic Considerations for Ring-Opening Polymerization

    PubMed Central

    2016-01-01

    The need for polymers for high-end applications, coupled with the desire to mimic nature’s macromolecular machinery fuels the development of innovative synthetic strategies every year. The recently acquired macromolecular-synthetic tools increase the precision and enable the synthesis of polymers with high control and low dispersity. However, regardless of the specificity, the polymerization behavior is highly dependent on the monomeric structure. This is particularly true for the ring-opening polymerization of lactones, in which the ring size and degree of substitution highly influence the polymer formation properties. In other words, there are two important factors to contemplate when considering the particular polymerization behavior of a specific monomer: catalytic specificity and thermodynamic equilibrium behavior. This perspective focuses on the latter and undertakes a holistic approach among the different lactones with regard to the equilibrium thermodynamic polymerization behavior and its relation to polymer synthesis. This is summarized in a monomeric overview diagram that acts as a presynthetic directional cursor for synthesizing highly specific macromolecules; the means by which monomer equilibrium conversion relates to starting temperature, concentration, ring size, degree of substitution, and its implications for polymerization behavior are discussed. These discussions emphasize the importance of considering not only the catalytic system but also the monomer size and structure relations to thermodynamic equilibrium behavior. The thermodynamic equilibrium behavior relation with a monomer structure offers an additional layer of complexity to our molecular toolbox and, if it is harnessed accordingly, enables a powerful route to both monomer formation and intentional macromolecular design. PMID:26795940

  13. Thermodynamic Presynthetic Considerations for Ring-Opening Polymerization.

    PubMed

    Olsén, Peter; Odelius, Karin; Albertsson, Ann-Christine

    2016-03-14

    The need for polymers for high-end applications, coupled with the desire to mimic nature's macromolecular machinery fuels the development of innovative synthetic strategies every year. The recently acquired macromolecular-synthetic tools increase the precision and enable the synthesis of polymers with high control and low dispersity. However, regardless of the specificity, the polymerization behavior is highly dependent on the monomeric structure. This is particularly true for the ring-opening polymerization of lactones, in which the ring size and degree of substitution highly influence the polymer formation properties. In other words, there are two important factors to contemplate when considering the particular polymerization behavior of a specific monomer: catalytic specificity and thermodynamic equilibrium behavior. This perspective focuses on the latter and undertakes a holistic approach among the different lactones with regard to the equilibrium thermodynamic polymerization behavior and its relation to polymer synthesis. This is summarized in a monomeric overview diagram that acts as a presynthetic directional cursor for synthesizing highly specific macromolecules; the means by which monomer equilibrium conversion relates to starting temperature, concentration, ring size, degree of substitution, and its implications for polymerization behavior are discussed. These discussions emphasize the importance of considering not only the catalytic system but also the monomer size and structure relations to thermodynamic equilibrium behavior. The thermodynamic equilibrium behavior relation with a monomer structure offers an additional layer of complexity to our molecular toolbox and, if it is harnessed accordingly, enables a powerful route to both monomer formation and intentional macromolecular design.

  14. Advanced Thermally Stable Coal-Derived Jet Fuels Compositional Factors Affecting Thermal Degradation of Jet Fuels

    DTIC Science & Technology

    1992-12-01

    shown in Figure 4.2 and the peaks are identified and quantified in Table 4.2. Phenol and alkylphenols are the most readily visible 137 Cf) C-)" M0 oý...transformation of the catechol and alkylphenolic structures in subbituminous coal is a loss of aryl-( -containing structures and a condensation of the phenols

  15. Preliminary study on the mode of occurrence of arsenic in high arsenic coals from southwest Guizhou Province

    USGS Publications Warehouse

    Ding, Z.; Zheng, B.; Zhang, Jiahua; Belkin, H.E.; Finkelman, R.B.; Zhao, F.; Zhou, D.; Zhou, Y.; Chen, C.

    1999-01-01

    Coal samples from high arsenic coal areas have been analyzed by electron microprobe analyzer (EMPA), scanning electron microscopy with an energy dispersive X-ray analyzer (SEM-EDX), X-ray diffraction analysis (XRD), low temperature ashing (LTA), transmission electron microscopy (TEM), X-ray absorption fine structure (XAFS), instrument neutron activation analysis (INAA) and wet chemical analysis. Although some As-bearing minerals such as pyrite, arsenopyrite, realgar (?), As-bearing sulfate, and As-bearing clays are found in the high arsenic coals, their contents do not account for the abundance of arsenic in the some coals. Analysis of the coal indicates that arsenic exists mainly in the form of As5+ and As3+, combined with compounds in the organic matrix. The occurrence of such exceptionally high arsenic contents in coal and the fact that the arsenic is dominantly organically associated are unique observations. The modes of occurrence of arsenic in high As-coals are discussed.

  16. Technological and economic aspects of coal biodesulfurisation.

    PubMed

    Klein, J

    1998-01-01

    The sulfur found in coal is either part of the molecular coal structure (organically bound sulfur), is contained in minerals such as pyrite (FeS2), or occurs in minor quantities in the form of sulfate and elemental sulfur. When pyrite crystals are finely distributed within the coal matrix, mechanical cleaning can only remove part of the pyrite. It can, however, be removed by microbial action requiring only mild conditions. The process involves simple equipment, almost no chemicals, but relatively long reaction times, and treatment of iron sulfate containing process water. Different process configurations are possible, depending on the coal particle size. Coal with particle sizes of less than 0.5 mm is preferably desulfurised in slurry reactors, while lump coal (> 0.5 mm) should be treated in heaps. Investment and operating costs are estimated for different process configurations on an industrial scale. Concerning the organically bound sulfur in coal there is up to now no promising biochemical pathway for the degradation and/or desulfurisation of such compounds.

  17. Damage evolution analysis of coal samples under cyclic loading based on single-link cluster method

    NASA Astrophysics Data System (ADS)

    Zhang, Zhibo; Wang, Enyuan; Li, Nan; Li, Xuelong; Wang, Xiaoran; Li, Zhonghui

    2018-05-01

    In this paper, the acoustic emission (AE) response of coal samples under cyclic loading is measured. The results show that there is good positive relation between AE parameters and stress. The AE signal of coal samples under cyclic loading exhibits an obvious Kaiser Effect. The single-link cluster (SLC) method is applied to analyze the spatial evolution characteristics of AE events and the damage evolution process of coal samples. It is found that a subset scale of the SLC structure becomes smaller and smaller when the number of cyclic loading increases, and there is a negative linear relationship between the subset scale and the degree of damage. The spatial correlation length ξ of an SLC structure is calculated. The results show that ξ fluctuates around a certain value from the second cyclic loading process to the fifth cyclic loading process, but spatial correlation length ξ clearly increases in the sixth loading process. Based on the criterion of microcrack density, the coal sample failure process is the transformation from small-scale damage to large-scale damage, which is the reason for changes in the spatial correlation length. Through a systematic analysis, the SLC method is an effective method to research the damage evolution process of coal samples under cyclic loading, and will provide important reference values for studying coal bursts.

  18. Polymerization-Defective Fibrinogen Variant gammaD364A Binds Knob “A” Peptide Mimic

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bowley,S.; Merenbloom, B.; Heroux, A.

    2008-01-01

    Fibrin polymerization is supported in part by interactions called 'A:a'. Crystallographic studies revealed ?364Asp is part of hole 'a' that interacts with knob 'A' peptide mimic, GPRP. Biochemical studies have shown ?364Asp is critical to polymerization, as polymerization of variants ?D364A, ?D364H, and ?D364V is exceptionally impaired. To understand the molecular basis for the aberrant function, we solved the crystal structure of fragment D from ?D364A. Surprisingly, the structure (rfD-?D364A+GP) showed near normal 'A:a' interactions with GPRP bound to hole 'a' and no change in the overall structure of ?D364A. Of note, inspection of the structure showed negative electrostatic potentialmore » inside hole 'a' was diminished by this substitution. We examined GPRP binding to the ?364Asp variants in solution by plasmin protection assay. We found no protection of either ?D364H or ?D364V but partial protection of ?D364A, indicating the peptide does not bind to either ?D364H or ?D364V and binds more weakly than normal to ?D364A. We also examined protection by calcium and found all variants were indistinguishable from normal, suggesting the global structures of the variants are not markedly different from normal. Our data imply that ?364Asp per se is not required for knob 'A' binding to hole 'a'; rather, this residue's negative charge has a critical role in the electrostatic interactions that facilitate the important first step in fibrin polymerization.« less

  19. Highly tunable porous organic polymer (POP) supports for metallocene-based ethylene polymerization

    NASA Astrophysics Data System (ADS)

    Wang, Xiong; Li, Zhenyou; Han, Xiaoyu; Han, Zhengang; Bai, Yongxiao

    2017-10-01

    Porous organic Polymers (POPs) can not only exhibit high specific surface area and pore volume, but also tunable pore size distribution. Herein, copolymers of 2-hydroxyethylmethylacrylate (HEMA) and divinylbenzene (DVB) with specific pore structure were synthesized via a dispersion polymerization strategy, and then immobilized metallocene catalysts with well-defined pore structure were obtained on the produced POP supports. The nitrogen sorption and Gel permeation chromatography (GPC) results demonstrate that the pore structure of the immobilized metallocene catalyst is highly dependent on the pore structure of the POPs, and the pore structure of metallocene catalysts or the POPs has a significant influence on the molecular chain growth of the produced polyethylene. By tuning the distribution of the active species scattered in the micro- and the narrow meso-pore range (roughly ≤4 nm), the chain growth of the polyolefin can be tailored effectively during the polymerization process, although differential scanning calorimetry (DSC) and temperature rising elution fractionation (TREF) results show that the chemical composition distributions (CCDs) of produced PE from the POPs-supported metallocene catalysts are not determined by polymerization activity or molecule chain length, but mainly by the active site species scattered in the supported catalysts. Scanning electron micrograph (SEM) shows that the produced polyethylene has highly porous fabric which consists of nanofiber and spherical beads of micron dimension.

  20. Activated-Lignite-Based Super Large Granular Slow-Release Fertilizers Improve Apple Tree Growth: Synthesis, Characterizations, and Laboratory and Field Evaluations.

    PubMed

    Tang, Yafu; Wang, Xinying; Yang, Yuechao; Gao, Bin; Wan, Yongshan; Li, Yuncong C; Cheng, Dongdong

    2017-07-26

    In this work, lignite, a low-grade coal, was modified using the solid-phase activation method with the aid of a Pd/CeO 2 nanoparticle catalyst to improve its pore structure and nutrient absorption. Results indicate that the adsorption ability of the activated lignite to NO 3 - , NH 4 + , H 2 PO 4 - , and K + was significantly higher than that of raw lignite. The activated lignite was successfully combined with the polymeric slow-release fertilizer, which exhibits typical slow-release behavior, to prepare the super large granular activated lignite slow-release fertilizer (SAF). In addition to the slow-release ability, the SAF showed excellent water-retention capabilities. Soil column leaching experiments further confirmed the slow-release characteristics of the SAF with fertilizer nutrient loss greatly reduced in comparison to traditional and slow-release fertilizers. Furthermore, field tests of the SAF in an orchard showed that the novel SAF was better than other tested fertilizers in improve the growth of young apple trees. Findings from this study suggest that the newly developed SAF has great potential to be used in apple cultivation and production systems in the future.

  1. Plasma-initiated polymerization of chitosan-based CS-g-P(AM-DMDAAC) flocculant for the enhanced flocculation of low-algal-turbidity water.

    PubMed

    Sun, Yongjun; Zhu, Chengyu; Sun, Wenquan; Xu, Yanhua; Xiao, Xuefeng; Zheng, Huaili; Wu, Huifang; Liu, Cuiyun

    2017-05-15

    In this work, a highly efficient and environmentally friendly chitosan-based graft flocculant, namely, acrylamide- and dimethyl diallyl ammonium chloride-grafted chitosan [CS-g-P(AM-DMDAAC)], was prepared successfully through plasma initiation. FTIR results confirmed the successful polymerization of CS-g-P(AM-DMDAAC) and P(AM-DMDAAC). P(AM-DMDAAC) was the copolymer of acrylamide- and dimethyl diallyl ammonium chloride. SEM results revealed that a densely cross-linked network structure formed on the surface. XRD results verified that the ordered crystal structure of chitosan in CS-g-P(AM-DMDAAC) was changed into an amorphous structure after plasma-induced polymerization. The flocculation results of low-algal-turbidity water further showed the optimal flocculation efficiency of turbidity removal rate, COD removal rate, and Chl-a removal rate were 99.02%, 96.11%, and 92.20%, respectively. The flocculation efficiency of CS-g-P(AM-DMDAAC) were significantly higher than those obtained by cationic polyacrylamide (CPAM) and Polymeric aluminum and iron (PAFC). This work provided a valuable basis for the design of eco-friendly naturally modified polymeric flocculants to enhance the flocculation of low-algal-turbidity water. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Update on coal in Big Horn basin, Montana and Wyoming

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jones, R.W.

    1983-08-01

    The Big Horn Coal basin is located within the topographic and structural basin of the same name and is defined by the limits of the Upper Cretaceous Mesaverde Formation in northwestern Wyoming and the Eagle Sandstone in south-central Montana. The coal in this basin ranges in rank from high volatile C bituminous (based primarily on resistance to weathering) to subbituminous B coal. In general, the Mesaverde and Eagle coals are highest in heat content, averaging over 10,500 Btu/lb; the Fort Union coals in the Red Lodge-Bear Creek and Grass Creek fields average about 10,200 Btu/lb and are second highest inmore » heating value. The Meeteetse Formation contains coals that average 9,800 Btu/lb, the lowest heating values in the basin. An average heating value for all coal in the basin is slightly less than 10,000 But/lb. The average sulfur content of all coals in this basin is less than 1%, with a range of 0.4 to 2.2%. Coal mining in the Big Horn Coal basin began in the late 1880s in the Red Lodge field and has continued to the present. Almost 53 million tons of coal have been mined in the basin; nearly 78% of this production (41 million tons) is from bituminous Fort Union coal beds in the Red Lodge-Bear Creek and Bridger coal fields, Montana. Original in-place resources for the Big Horn Coal basin are given by rank of coal: 1,265.12 million tons of bituminous coal resources have been calculated for the Silvertip field, Wyoming, and the Red Lodge-Bear Creek and Bridger fields, Montana; 563.78 million tons of subbituminous resources have been calculated for the remaining Wyoming coal fields.« less

  3. Particle-filled microporous materials

    DOEpatents

    McAllister, J.W.; Kinzer, K.E.; Mrozinski, J.S.; Johnson, E.J.; Dyrud, J.F.

    1990-09-18

    A microporous particulate-filled thermoplastic polymeric article is provided. The article can be in the form of a film, a fiber, or a tube. The article has a thermoplastic polymeric structure having a plurality of interconnected passageways to provide a network of communicating pores. The microporous structure contains discrete submicron or low micron-sized particulate filler, the particulate filler being substantially non-agglomerated. 3 figs.

  4. Effect of Water Invasion on Outburst Predictive Index of Low Rank Coals in Dalong Mine

    PubMed Central

    Jiang, Jingyu; Cheng, Yuanping; Mou, Junhui; Jin, Kan; Cui, Jie

    2015-01-01

    To improve the coal permeability and outburst prevention, coal seam water injection and a series of outburst prevention measures were tested in outburst coal mines. These methods have become important technologies used for coal and gas outburst prevention and control by increasing the external moisture of coal or decreasing the stress of coal seam and changing the coal pore structure and gas desorption speed. In addition, techniques have had a significant impact on the gas extraction and outburst prevention indicators of coal seams. Globally, low rank coals reservoirs account for nearly half of hidden coal reserves and the most obvious feature of low rank coal is the high natural moisture content. Moisture will restrain the gas desorption and will affect the gas extraction and accuracy of the outburst prediction of coals. To study the influence of injected water on methane desorption dynamic characteristics and the outburst predictive index of coal, coal samples were collected from the Dalong Mine. The methane adsorption/desorption test was conducted on coal samples under conditions of different injected water contents. Selective analysis assessed the variations of the gas desorption quantities and the outburst prediction index (coal cutting desorption index). Adsorption tests indicated that the Langmuir volume of the Dalong coal sample is ~40.26 m3/t, indicating a strong gas adsorption ability. With the increase of injected water content, the gas desorption amount of the coal samples decreased under the same pressure and temperature. Higher moisture content lowered the accumulation desorption quantity after 120 minutes. The gas desorption volumes and moisture content conformed to a logarithmic relationship. After moisture correction, we obtained the long-flame coal outburst prediction (cutting desorption) index critical value. This value can provide a theoretical basis for outburst prediction and prevention of low rank coal mines and similar occurrence conditions of coal seams. PMID:26161959

  5. Barnacle cement: a polymerization model based on evolutionary concepts

    PubMed Central

    Dickinson, Gary H.; Vega, Irving E.; Wahl, Kathryn J.; Orihuela, Beatriz; Beyley, Veronica; Rodriguez, Eva N.; Everett, Richard K.; Bonaventura, Joseph; Rittschof, Daniel

    2009-01-01

    Summary Enzymes and biochemical mechanisms essential to survival are under extreme selective pressure and are highly conserved through evolutionary time. We applied this evolutionary concept to barnacle cement polymerization, a process critical to barnacle fitness that involves aggregation and cross-linking of proteins. The biochemical mechanisms of cement polymerization remain largely unknown. We hypothesized that this process is biochemically similar to blood clotting, a critical physiological response that is also based on aggregation and cross-linking of proteins. Like key elements of vertebrate and invertebrate blood clotting, barnacle cement polymerization was shown to involve proteolytic activation of enzymes and structural precursors, transglutaminase cross-linking and assembly of fibrous proteins. Proteolytic activation of structural proteins maximizes the potential for bonding interactions with other proteins and with the surface. Transglutaminase cross-linking reinforces cement integrity. Remarkably, epitopes and sequences homologous to bovine trypsin and human transglutaminase were identified in barnacle cement with tandem mass spectrometry and/or western blotting. Akin to blood clotting, the peptides generated during proteolytic activation functioned as signal molecules, linking a molecular level event (protein aggregation) to a behavioral response (barnacle larval settlement). Our results draw attention to a highly conserved protein polymerization mechanism and shed light on a long-standing biochemical puzzle. We suggest that barnacle cement polymerization is a specialized form of wound healing. The polymerization mechanism common between barnacle cement and blood may be a theme for many marine animal glues. PMID:19837892

  6. Intrinsic embedded sensors for polymeric mechatronics: flexure and force sensing.

    PubMed

    Jentoft, Leif P; Dollar, Aaron M; Wagner, Christopher R; Howe, Robert D

    2014-02-25

    While polymeric fabrication processes, including recent advances in additive manufacturing, have revolutionized manufacturing, little work has been done on effective sensing elements compatible with and embedded within polymeric structures. In this paper, we describe the development and evaluation of two important sensing modalities for embedding in polymeric mechatronic and robotic mechanisms: multi-axis flexure joint angle sensing utilizing IR phototransistors, and a small (12 mm), three-axis force sensing via embedded silicon strain gages with similar performance characteristics as an equally sized metal element based sensor.

  7. Melting line of polymeric nitrogen

    NASA Astrophysics Data System (ADS)

    Yakub, L. N.

    2013-05-01

    We made an attempt to predict location of the melting line of polymeric nitrogen using two equations for Helmholtz free energy: proposed earlier for cubic gauche-structure and developed recently for liquid polymerized nitrogen. The P-T relation, orthobaric densities and latent heat of melting were determined using a standard double tangent construction. The estimated melting temperature decreases with increasing pressure, alike the temperature of molecular-nonmolecular transition in solid. We discuss the possibility of a triple point (solid-molecular fluid-polymeric fluid) at ˜80 GPa and observed maximum of melting temperature of nitrogen.

  8. Intrinsic Embedded Sensors for Polymeric Mechatronics: Flexure and Force Sensing

    PubMed Central

    Jentoft, Leif P.; Dollar, Aaron M.; Wagner, Christopher R.; Howe, Robert D.

    2014-01-01

    While polymeric fabrication processes, including recent advances in additive manufacturing, have revolutionized manufacturing, little work has been done on effective sensing elements compatible with and embedded within polymeric structures. In this paper, we describe the development and evaluation of two important sensing modalities for embedding in polymeric mechatronic and robotic mechanisms: multi-axis flexure joint angle sensing utilizing IR phototransistors, and a small (12 mm), three-axis force sensing via embedded silicon strain gages with similar performance characteristics as an equally sized metal element based sensor. PMID:24573310

  9. Noncovalent assembly. A rational strategy for the realization of chain-growth supramolecular polymerization.

    PubMed

    Kang, Jiheong; Miyajima, Daigo; Mori, Tadashi; Inoue, Yoshihisa; Itoh, Yoshimitsu; Aida, Takuzo

    2015-02-06

    Over the past decade, major progress in supramolecular polymerization has had a substantial effect on the design of functional soft materials. However, despite recent advances, most studies are still based on a preconceived notion that supramolecular polymerization follows a step-growth mechanism, which precludes control over chain length, sequence, and stereochemical structure. Here we report the realization of chain-growth polymerization by designing metastable monomers with a shape-promoted intramolecular hydrogen-bonding network. The monomers are conformationally restricted from spontaneous polymerization at ambient temperatures but begin to polymerize with characteristics typical of a living mechanism upon mixing with tailored initiators. The chain growth occurs stereoselectively and therefore enables optical resolution of a racemic monomer. Copyright © 2015, American Association for the Advancement of Science.

  10. Large Scale Laser Two-Photon Polymerization Structuring for Fabrication of Artificial Polymeric Scaffolds for Regenerative Medicine

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Malinauskas, M.; Purlys, V.; Zukauskas, A.

    2010-11-10

    We present a femtosecond Laser Two-Photon Polymerization (LTPP) system of large scale three-dimensional structuring for applications in tissue engineering. The direct laser writing system enables fabrication of artificial polymeric scaffolds over a large area (up to cm in lateral size) with sub-micrometer resolution which could find practical applications in biomedicine and surgery. Yb:KGW femtosecond laser oscillator (Pharos, Light Conversion. Co. Ltd.) is used as an irradiation source (75 fs, 515 nm (frequency doubled), 80 MHz). The sample is mounted on wide range linear motor driven stages having 10 nm sample positioning resolution (XY--ALS130-100, Z--ALS130-50, Aerotech, Inc.). These stages guarantee anmore » overall travelling range of 100 mm into X and Y directions and 50 mm in Z direction and support the linear scanning speed up to 300 mm/s. By moving the sample three-dimensionally the position of laser focus in the photopolymer is changed and one is able to write complex 3D (three-dimensional) structures. An illumination system and CMOS camera enables online process monitoring. Control of all equipment is automated via custom made computer software ''3D-Poli'' specially designed for LTPP applications. Structures can be imported from computer aided design STereoLihography (stl) files or programmed directly. It can be used for rapid LTPP structuring in various photopolymers (SZ2080, AKRE19, PEG-DA-258) which are known to be suitable for bio-applications. Microstructured scaffolds can be produced on different substrates like glass, plastic and metal. In this paper, we present microfabricated polymeric scaffolds over a large area and growing of adult rabbit myogenic stem cells on them. Obtained results show the polymeric scaffolds to be applicable for cell growth practice. It exhibit potential to use it for artificial pericardium in the experimental model in the future.« less

  11. Large Scale Laser Two-Photon Polymerization Structuring for Fabrication of Artificial Polymeric Scaffolds for Regenerative Medicine

    NASA Astrophysics Data System (ADS)

    Malinauskas, M.; Purlys, V.; Žukauskas, A.; Rutkauskas, M.; Danilevičius, P.; Paipulas, D.; Bičkauskaitė, G.; Bukelskis, L.; Baltriukienė, D.; Širmenis, R.; Gaidukevičiutė, A.; Bukelskienė, V.; Gadonas, R.; Sirvydis, V.; Piskarskas, A.

    2010-11-01

    We present a femtosecond Laser Two-Photon Polymerization (LTPP) system of large scale three-dimensional structuring for applications in tissue engineering. The direct laser writing system enables fabrication of artificial polymeric scaffolds over a large area (up to cm in lateral size) with sub-micrometer resolution which could find practical applications in biomedicine and surgery. Yb:KGW femtosecond laser oscillator (Pharos, Light Conversion. Co. Ltd.) is used as an irradiation source (75 fs, 515 nm (frequency doubled), 80 MHz). The sample is mounted on wide range linear motor driven stages having 10 nm sample positioning resolution (XY—ALS130-100, Z—ALS130-50, Aerotech, Inc.). These stages guarantee an overall travelling range of 100 mm into X and Y directions and 50 mm in Z direction and support the linear scanning speed up to 300 mm/s. By moving the sample three-dimensionally the position of laser focus in the photopolymer is changed and one is able to write complex 3D (three-dimensional) structures. An illumination system and CMOS camera enables online process monitoring. Control of all equipment is automated via custom made computer software "3D-Poli" specially designed for LTPP applications. Structures can be imported from computer aided design STereoLihography (stl) files or programmed directly. It can be used for rapid LTPP structuring in various photopolymers (SZ2080, AKRE19, PEG-DA-258) which are known to be suitable for bio-applications. Microstructured scaffolds can be produced on different substrates like glass, plastic and metal. In this paper, we present microfabricated polymeric scaffolds over a large area and growing of adult rabbit myogenic stem cells on them. Obtained results show the polymeric scaffolds to be applicable for cell growth practice. It exhibit potential to use it for artificial pericardium in the experimental model in the future.

  12. Research on solvent-refined coal. Quarterly technical progress report, April 1, 1981-June 30, 1981

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1981-10-01

    This report describes progress on the Research on Solvent Refined Coal project by The Pittsburg and Midway Coal Mining Co.'s Merriam Laboratory during the second quarter of 1981. Alexander Mine coal was evaluated as a feedstock for major liquefaction facilities and had a yield structure similar to other reactive Pittsburgh seam coals at standard SRC II conditions. Two lots of coal from the Ireland Mine (Pittsburgh seam) were found to be of nearly the same composition and produced essentially the same yields. Two experiments in which coal-derived nonvolatile organic matter was processed without fresh coal feed indicate constant rates ofmore » conversion of SRC to oil and gas. Insoluble organic matter (IOM) remained unconverted. The naphtha and middle distillate products from the deep conversion contained less sulfur but more nitrogen than those from conventional SRC II processing. Encouraging results were obtained when a very small amount of iron oxide dispersed on alumina was added to Kaiparowits coal which cannot be processed at normal SRC II conditions without added catalyst. Subbituminous coals from the McKinley and Edna Mines were processed successfully with added pyrite but would not run when the added catalyst was removed.« less

  13. Geochemistry of autochthonous and hypautochthonous siderite-dolomite coal-balls (Foord Seam, Bolsovian, Upper Carboniferous), Nova Scotia, Canada

    USGS Publications Warehouse

    Zodrow, E.L.; Lyons, P.C.; Millay, M.A.

    1996-01-01

    The 11-13 m thick Foord Seam in the fault-bounded Stellarton Basin, Nova Scotia, is the thickest seam from the Euramerican floral province known to contain coal-balls. In addition to the first discovery of autochthonous coal-balls in the Foord Seam, Nova Scotia, its shale parting also contains hypautochthonous coal-balls with histologically preserved plant structures. The coal-ball discovery helps fill a stratigraphic gap in coal-ball occurrences in the upper Carboniferous (Bolsovian) of Euramerica. The autochthonous and hypautochthonous coal-balls have a similar mineralogical composition and are composed of siderite (81-100%), dolomite-ankerite (0-19%), minor quartz and illite, and trace amounts of 'calcite'. Similar is also their permineralizing mineralogy, which consists of dolomite-ankerite and siderite. Their low pyrite content and carbonate mineralogy, and nonmarine origin, differentiates the Foord Seam coal-balls from other Euramerican coal-ball occurrences. A preliminary geochemical model, which is based on oxygen and carbon isotopic data, indicates that siderite in both the autochthonous and hypautochthonous coal-balls is of very early diagenetic (nonmarine) origin from 13C-enriched bicarbonate derived from bacterial methanogenesis of organic matter.

  14. Post polymerization cure shape memory polymers

    DOEpatents

    Wilson, Thomas S.; Hearon, II, Michael Keith; Bearinger, Jane P.

    2017-01-10

    This invention relates to chemical polymer compositions, methods of synthesis, and fabrication methods for devices regarding polymers capable of displaying shape memory behavior (SMPs) and which can first be polymerized to a linear or branched polymeric structure, having thermoplastic properties, subsequently processed into a device through processes typical of polymer melts, solutions, and dispersions and then crossed linked to a shape memory thermoset polymer retaining the processed shape.

  15. Post polymerization cure shape memory polymers

    DOEpatents

    Wilson, Thomas S; Hearon, Michael Keith; Bearinger, Jane P

    2014-11-11

    This invention relates to chemical polymer compositions, methods of synthesis, and fabrication methods for devices regarding polymers capable of displaying shape memory behavior (SMPs) and which can first be polymerized to a linear or branched polymeric structure, having thermoplastic properties, subsequently processed into a device through processes typical of polymer melts, solutions, and dispersions and then crossed linked to a shape memory thermoset polymer retaining the processed shape.

  16. Elucidation of a side reaction occurring during nitroxide-mediated polymerization of cyclic ketene acetals by tandem mass spectrometric end-group analysis of aliphatic polyesters.

    PubMed

    Albergaria Pereira, Bruna de Fátima; Tardy, Antoine; Monnier, Valérie; Guillaneuf, Yohann; Gigmes, Didier; Charles, Laurence

    2015-12-15

    In order to prevent side reactions while developing new polymerization processes, their mechanism has to be understood and one first key insight is the structure of the end-groups in polymeric by-products. The synthetic method scrutinized here is the nitroxide-mediated polymerization (NMP) of a cyclic ketene acetal, a promising alternative process to the production of polyesters. Polymer end-group characterization was performed by mass spectrometry (MS), combining elemental composition information derived from accurate mass data in the MS mode with fragmentation features recorded in the MS/MS mode. Electrospray was used as the ionization method to ensure the integrity of original chain terminations and a quadrupole time-of-flight (QTOF) instrument was employed for high-resolution mass measurements in both MS and tandem mass spectrometry (MS/MS) modes. Occurrence of side reactions in the studied polymerization method, first evidenced by an unusual increase in dispersity with conversion, was confirmed in MS with the detection of two polymeric impurities in addition to the expected species. Fragmentation rules were first established for this new polyester family in order to derive useful structural information from MS/MS data. In addition to a usual NMP by-product, the initiating group of the second polymeric impurities revealed the degradation of the nitroxide moiety. Unambiguous MS/MS identification of end-groups in by-products sampled from the polymerization medium allowed an unusual side reaction to be identified during the NMP preparation of polyesters. On-going optimization of the polymerization method aims at preventing this undesired process. Copyright © 2015 John Wiley & Sons, Ltd.

  17. Minor element distribution in iron disulfides in coal: a geochemical review

    USGS Publications Warehouse

    Kolker, Allan

    2012-01-01

    Electron beam microanalysis of coal samples in U.S. Geological Survey (USGS) labs confirms that As is the most abundant minor constituent in Fe disulfides in coal and that Se, Ni, and other minor constituents are present less commonly and at lower concentrations than those for As. In nearly all cases, Hg occurs in Fe disulfides in coal at concentrations below detection by electron beam instruments. Its presence is shown by laser ablation ICP-MS, by selective leaching studies of bulk coal, and by correlation with Fe disulfide proxies such as total Fe and pyritic sulfur. Multiple generations of Fe disulfides are present in coal. These commonly show grain-to-grain and within-grain minor- or trace element compositional variation that is a function of the early diagenetic, coalification, and post-coalification history of the coal. Framboidal pyrite is almost always the earliest Fe disulfide generation, as shown by overgrowths of later Fe disulfides which may include pyrite or marcasite. Cleat- (or vein) pyrite (or marcasite) is typically the latest Fe disulfide generation, as shown by cross-cutting relations. Cleat pyrite forms by fluid migration within a coal basin and consequently may be enriched in elements such as As by deposition from compaction-driven fluids, metal enriched basinal brines or hydrothermal fluids. In some cases, framboidal pyrite shows preferential Ni enrichment with respect to co-occurring pyrite forms. This is consistent with bacterial complexing of metals in anoxic sediments and derivation of framboidal pyrite from greigite (Fe3S4), an Fe monosulfide precursor to framboidal pyrite having the thio-spinel structure which accommodates transition metals. Elements such as As, Se, and Sb substitute for S in the pyrite structure whereas metals, including transition metals, Hg and Pb, are thought to substitute for Fe. Understanding the distribution of minor and trace elements in Fe disulfides in coal has important implications for their availability to the environment through coal mining and use, as well as for potential reduction by coal preparation, and for delineating diagenetic compositional changes throughout and after coal formation.

  18. Cumulative potential hydrologic impacts of surface coal mining in the eastern Powder River structural basin, northeastern Wyoming

    USGS Publications Warehouse

    Martin, L.J.; Naftz, D.L.; Lowham, H.W.; Rankl, J.G.

    1988-01-01

    There are 16 existing and six proposed surface coal mines in the eastern Powder River structural basin of northeastern Wyoming. Coal mining companies predict water level declines of 5 ft or more in the Wasatch aquifer to extend form about 1,000 to about 2,000 ft beyond the mine pits. The predicted 5 ft water level decline in the Wyodak coal aquifer generally extends 4-8 mi beyond the lease areas. About 3,000 wells are in the area of potential cumulative water level declines resulting from all anticipated mining. Of these 3,000 wells, about 1,200 are outside the areas of anticipated mining: about 1,000 wells supply water for domestic or livestock uses, and about 200 wells supply water for municipal, industrial, irrigation, and miscellaneous uses. The 1,800 remaining wells are used by coal mining companies. Future surface coal mining probably will result in postmining groundwater of similar quality to that currently present in the study area. By use of geochemical modeling techniques, the results of a hypothetical reaction path exercise indicate the potential for marked improvements in postmining water quality because of chemical reactions as postmining groundwater with a large dissolved solids concentration (3,540 mg/L) moves into a coal aquifer with relatively small dissolved solids concentrations (910 mg/L). Results of the modeling exercise also indicate geochemical conditions that are most ideal for large decreases in dissolved solids concentrations in coal aquifers receiving recharge from a spoil aquifer. (Lantz-PTT)

  19. Distribution of trace elements in selected pulverized coals as a function of particle size and density

    USGS Publications Warehouse

    Senior, C.L.; Zeng, T.; Che, J.; Ames, M.R.; Sarofim, A.F.; Olmez, I.; Huggins, Frank E.; Shah, N.; Huffman, G.P.; Kolker, A.; Mroczkowski, S.; Palmer, C.; Finkelman, R.

    2000-01-01

    Trace elements in coal have diverse modes of occurrence that will greatly influence their behavior in many coal utilization processes. Mode of occurrence is important in determining the partitioning during coal cleaning by conventional processes, the susceptibility to oxidation upon exposure to air, as well as the changes in physical properties upon heating. In this study, three complementary methods were used to determine the concentrations and chemical states of trace elements in pulverized samples of four US coals: Pittsburgh, Illinois No. 6, Elkhorn and Hazard, and Wyodak coals. Neutron Activation Analysis (NAA) was used to measure the absolute concentration of elements in the parent coals and in the size- and density-fractionated samples. Chemical leaching and X-ray absorption fine structure (XAFS) spectroscopy were used to provide information on the form of occurrence of an element in the parent coals. The composition differences between size-segregated coal samples of different density mainly reflect the large density difference between minerals, especially pyrite, and the organic portion of the coal. The heavy density fractions are therefore enriched in pyrite and the elements associated with pyrite, as also shown by the leaching and XAFS methods. Nearly all the As is associated with pyrite in the three bituminous coals studied. The sub-bituminous coal has a very low content of pyrite and arsenic; in this coal arsenic appears to be primarily organically associated. Selenium is mainly associated with pyrite in the bituminous coal samples. In two bituminous coal samples, zinc is mostly in the form of ZnS or associated with pyrite, whereas it appears to be associated with other minerals in the other two coals. Zinc is also the only trace element studied that is significantly more concentrated in the smaller (45 to 63 ??m) coal particles.

  20. Graft Polymerization of Acrylic Acid on a Polytetrafluoroethylene Panel by an Inductively Coupled Plasma

    NASA Astrophysics Data System (ADS)

    Lan, Yan; You, Qingliang; Cheng, Cheng; Zhang, Suzhen; Ni, Guohua; Nagatsu, M.; Meng, Yuedong

    2011-02-01

    Surface modification on a polytetrafluoroethylene (PTFE) panel was performed with sequential nitrogen plasma treatments and surface-initiated polymerization. By introducing COO- groups to the surface of the PTFE panel through grafting polymerization of acrylic acid (AA), a transparent poly (acrylic acid) (PAA) membrane was achieved from acrylic acid solution. Grafting polymerization initiating from the active groups was achieved on the PTFE panel surface after the nitrogen plasma treatment. Utilizing the acrylic acid as monomers, with COO- groups as cross link sites to form reticulation structure, a transparent poly (acrylic acid) membrane with arborescent macromolecular structure was formed on the PTFE panel surface. Analysis methods, such as fourier transform infrared spectroscopy (FTIR), microscopy and X-ray photoelectron spectroscopy (XPS), were utilized to characterize the structures of the macromolecule membrane on the PTFE panel surface. A contact angle measurement was performed to characterize the modified PTFE panels. The surface hydrophilicities of modified PTFE panels were significantly enhanced after the plasma treatment. It was shown that the grafting rate is related to the treating time and the power of plasma.

  1. Thermal behaviour and microanalysis of coal subbituminus

    NASA Astrophysics Data System (ADS)

    Heriyanti; Prendika, W.; Ashyar, R.; Sutrisno

    2018-04-01

    Differential scanning calorimetry (DSC) and X-ray powder diffraction (XRD) is used to study the thermal behaviour of sub-bituminous coal. The DSC experiment was performed in air atmosphere up to 125 °C at a heating rate of 25 °C min1. The DSC curve showed that the distinct transitional stages in the coal samples studied. Thermal heating temperature intervals, peak and dissociation energy of the coal samples were also determined. The XRD analysis was used to evaluate the diffraction pattern and crystal structure of the compounds in the coal sample at various temperatures (25-350 °C). The XRD analysis of various temperatures obtained compounds from the coal sample, dominated by quartz (SiO2) and corundum (Al2O3). The increase in temperature of the thermal treatment showed a better crystal formation.

  2. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wei, Chan Yi, E-mail: vicchanyiwei@hotmail.com; Ongkudon, Clarence M., E-mail: clarence@ums.edu.my; Kansil, Tamar, E-mail: tamarkansil87@gmail.com

    Modern day synthesis protocols of methacrylate monolithic polymer adsorbent are based on existing polymerization blueprint without a thorough understanding of the dynamics of pore structure and formation. This has resulted in unproductiveness of polymer adsorbent consequently affecting purity and recovery of final product, productivity, retention time and cost effectiveness of the whole process. The problems magnified in monolith scaling-up where internal heat buildup resulting from external heating and high exothermic polymerization reaction was reflected in cracking of the adsorbent. We believe that through careful and precise control of the polymerization kinetics and parameters, it is possible to prepare macroporous methacrylatemore » monolithic adsorbents with controlled pore structures despite being carried out in an unstirred mould. This research involved the study of the effect of scaling-up on pore morphology of monolith, in other words, porous polymethacrylate adsorbents that were prepared via bulk free radical polymerization process by imaging the porous morphology of polymethacrylate with scanning electron microscope.« less

  3. Synthesis of nanostructured bio-related materials by hybridization of synthetic polymers with polysaccharides or saccharide residues.

    PubMed

    Kaneko, Yoshiro; Kadokawa, Jun-Ichi

    2006-01-01

    In the first part of this review, we describe the synthesis of nanostructured hybrid materials composed of polysaccharides and synthetic polymers. Amylose-synthetic polymer inclusion complexes were synthesized by amylose-forming polymerization using phosphorylase enzyme in the presence of synthetic polymers such as polyethers and polyesters. Alginate-polymethacrylate hybrid materials were prepared by free-radical polymerization of cationic methacrylate in the presence of sodium alginate. These methods allow the simultaneous control of the nanostructure with polymerization, giving well-defined hybrid materials. In the second part of this review, we describe the synthesis of novel glycopolymers with rigid structures. Polyaniline-based glycopolymers were synthesized by means of oxidative polymerization of N-glycosylaniline. Polysiloxane-based glycopolymers were prepared by means of introduction of sugar-lactone to the rodlike polysiloxane. These glycopolymers had regular higher-ordered structures due to their rigid polymer backbones, resulting in control of the three-dimensional array of sugar-residues.

  4. Influence of high-energy impact on the physical and technical characteristics of coal fuels

    NASA Astrophysics Data System (ADS)

    Mal'tsev, L. I.; Belogurova, T. P.; Kravchenko, I. V.

    2017-08-01

    Currently, in the world's large-scale coal-fired power industry, the combustion of pulverized coal is the most widely spread technology of combusting the coals. In recent years, the micropulverization technology for preparation and combustion of the coal has been developed in this field. As applied to the small-scale power industry, the method of combusting the coal in the form of a coal-water slurry has been explored for years. Fine coal powders are produced and used in the pulverized-coal gasification. Therefore, the coal preparation methods that involve high-dispersion disintegration of coals attract the greatest interest. The article deals with the problems of high-energy impact on the coal during the preparation of pulverized-coal fuels and coal-water slurries, in particular, during the milling of the coal in ball drum mills and the subsequent regrinding in disintegrators or the cavitation treatment of the coal-water slurries. The investigations were conducted using samples of anthracite and lignite from Belovskii open-pit mine (Kuznetsk Basin). It is shown that both the disintegration and the cavitation treatment are efficient methods for controlling the fuel characteristics. Both methods allow increasing the degree of dispersion of the coal. The content of the small-sized particles reground by cavitation considerably exceeds the similar figure obtained using the disintegrator. The specific surface area of the coal is increased by both cavitation and disintegration with the cavitation treatment producing a considerably greater effect. Being subjected to the cavitation treatment, most coal particles assume the form of a split characterized by the thermodynamically nonequilibrium state. Under external action, in particular, of temperature, the morphological structure of such pulverized materials changes faster and, consequently, the combustion of the treated coal should occur more efficiently. The obtained results are explained from the physical point of view.

  5. Low-Temperature (75 To 400°C) Oxidation Study Of Coal By Diffuse Reflectance Infrared Fourier Transform (DRIFT) Spectroscopy

    NASA Astrophysics Data System (ADS)

    Smyrl, Norman R.; Fuller, E. L.

    1989-12-01

    In situ low-temperature air oxidation studies of subbituminous coal have been performed at 77, 125, 200, 300, and 400°C by diffuse reflectance Fourier transform (DRIFT) spectroscopy. The oxidation reaction proceeds via oxygen insertion at aliphatic sites in the coal structure, which progressively produces aldo/keto groups, acid groups, and acid anhydride entities with the simultaneous consumption of hydrogen at these sites. The production of anhydrides occurs even at the lowest temperature (77?°C), but only above 200°C is there sufficient mobility of the acid functionalities for major quantities of the anhydride species to be formed. Above 400C, the anhydro groups predominate in the steady-state production of carbon dioxide and water vapor. In addition to the detailed information concerning the carbonyl species, the spectra of the oxidized coal reveal some new information regarding the aromatic C-H stretching bands, which can be studied in some detail unencumbered by interference from the aliphatic bands that have been removed in the oxidation process. Further details related to the aromatic bands are revealed by deuterium exchange of the remaining 0-H groups (primarily phenolic type 0-H) in the oxidized coal structure. This exchange removes these bands from overlap with the broad 0-H stretching band resulting from hydrogen bonding of the 0-H groups. The present study reveals further merits of in situ DRIFT analysis in extending the knowledge of coal structure and reactions. The study also indicates much potential for further work.

  6. Innovative cellular distance structures from polymeric and metallic threads

    NASA Astrophysics Data System (ADS)

    Wieczorek, F.; Trümper, W.; Cherif, C.

    2017-10-01

    Knitting allows a high individual adaptability of the geometry and properties of flat-knitted spacer fabrics. This offers advantages for the specific adjustment of the mechanical properties of innovative composites based on highly viscous matrix systems such as bone cement, elastomer or foam and cellular reinforcing structures made from e. g. polymeric monofilaments or metallic wires. The prerequisite is the availability of binding solutions for highly productive production of functional, cellular, self-stabilized spacer flat knitted fabrics as supporting and functionalized structures.

  7. Fabrication of submicron proteinaceous structures by direct laser writing

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Serien, Daniela; Takeuchi, Shoji, E-mail: takeuchi@iis.u-tokyo.ac.jp; ERATO Takeuchi Biohybrid Innovation Project, Japan Science and Technology Agency, 4-6-1 Komaba, Meguro-ku, 153-8505 Tokyo

    In this paper, we provide a characterization of truly free-standing proteinaceous structures with submicron feature sizes depending on the fabrication conditions by model-based analysis. Protein cross-linking of bovine serum albumin is performed by direct laser writing and two-photon excitation of flavin adenine dinucleotide. We analyze the obtainable fabrication resolution and required threshold energy for polymerization. The applied polymerization model allows prediction of fabrication conditions and resulting fabrication size, alleviating the application of proteinaceous structure fabrication.

  8. Injectable Ceramic Microcast Silicon Carbonitride (SiCN) Microelectromechanical System (MEMS) for Extreme Temperature Environments with Extension: Micro Packages for Nano-Devices

    DTIC Science & Technology

    2004-01-01

    pyrolyzed to produce the ceramic (SiCN) parts, or they may be retained in the polymeric state and used as high-temperature polymer /glass MEMS devices. Two...structure and the SU8 /wafer is weak due to the Teflon coating. (j) A free standing polymer structure results. The structure is then crosslinked and... polymer . Further efforts are necessary to identify the least damaging rinsing chemicals, that is, chemicals which would not contaminate polymerized

  9. Coal liquefaction in an inorganic-organic medium. [DOE patent application

    DOEpatents

    Vermeulen, T.; Grens, E.A. II; Holten, R.R.

    Improved process for liquefaction of coal by contacting pulverized coal in an inorganic-organic medium solvent system containing a ZnCl/sub 2/ catalyst, a polar solvent with the structure RX where X is one of the elements O, N, S, or P, and R is hydrogen or a lower hydrocarbon radical; the solvent system can contain a hydrogen donor solvent (and must when RX is water) which is immiscible in the ZnCl/sub 2/ and is a hydroaromatic hydrocarbon selected from tetralin, dihydrophenanthrene, dihydroanthracene or a hydrogenated coal derived hydroaromatic hydrocarbon distillate fraction.

  10. Ocular findings in coal miners diagnosed with pneumoconiosis.

    PubMed

    Ayar, Orhan; Orcun Akdemir, Mehmet; Erboy, Fatma; Yazgan, Serpil; Hayri Ugurbas, Suat

    2017-06-01

    Our study aimed at evaluating ocular findings and structural changes in coal mine workers who were chronically exposed to coal mine dust and diagnosed with pneumoconiosis. Ocular findings of 161 eyes of 81 patients diagnosed with pneumoconiosis who had previously worked or are currently working in coal mines were analyzed. Forty-six coal mine workers and sex matched healthy people (n = 20) participated in the study. Workers who had early changes of pneumoconiosis were included in Group 1 (n = 17), workers diagnosed with pneumoconiosis were included in Group 2 (n = 29), and healthy subjects were included in Group 3 (n = 20). Outcome measures were the difference in peripapillary retinal nerve fiber layer (RNFL) thickness, choroidal thickness (CT), central macular thickness (CMT) and tear function tests between the groups. RNFL thickness values in Group 1 and 2 were lower than in Group 3, the control group, in all quadrants except the temporal quadrant. However, there was no statistically significant difference in peripapillary RNFL thickness values in any quadrants among the three groups (p > 0.05). Central subfoveal choroidal thickness and CMT measurements were thinner in Group 1 and 2 than in the control group. However, this difference among groups was not statistically significant (p > 0.05). Mean schirmer's test result was 8.8 ± 1.6 mm in group 1, 7.1 ± 1.8 mm in Group 2 and 11.5 ± 3.6 mm in the control group. Mean tear break up time (BUT) test result was 7.1 ± 1.3 seconds (sec) in Group 1, 6.5 ± 1.8 sec in Group 2 and 10.4 ± 2.9 s in the control group. The Schirmer's test and BUT test results were both statistically significantly lower in coal mine workers (Group 1 and 2) compared to the control group. Group 1 and Group 2 did not show statistically significant difference in terms of Schirmer's test and BUT test results. The association between pneumoconiosis and coal mine dust contiguity is thought to be due to the effect of coal dust by producing chronic inflammation. In addition, there are several trace elements in coal dust which are toxic to vital tissues. In this study, ocular findings suggest that systemic levels of trace elements and chronic inflammation may not reach to a level that influences ocular structures. Nonetheless, tear functions seem to be affected in coal mine workers. This study suggests that the systemic effect of coal mine dust in ocular structures is not evident. However, direct contact with coal mine and fume leads to a decrease in tear function tests.

  11. Research on power source structure optimization for East China Power Grid

    NASA Astrophysics Data System (ADS)

    Xu, Lingjun; Sang, Da; Zhang, Jianping; Tang, Chunyi; Xu, Da

    2017-05-01

    The structure of east china power grid is not reasonable for the coal power takes a much higher proportion than hydropower, at present the coal power takes charge of most peak load regulation, and the pressure of peak load regulation cannot be ignored. The nuclear power, wind power, photovoltaic, other clean energy and hydropower, coal power and wind power from outside will be actively developed in future, which increases the pressure of peak load regulation. According to development of economic and social, Load status and load prediction, status quo and planning of power source and the characteristics of power source, the peak load regulation balance is carried out and put forward a reasonable plan of power source allocation. The ultimate aim is to optimize the power source structure and to provide reference for power source allocation in east china.

  12. The History of Current State of the Art of Propylene Polymerization Catalysts.

    ERIC Educational Resources Information Center

    Goodall, Brian L.

    1986-01-01

    Outlines the development of the modern catalysts for propylene polymerization, considering the historical background; structure of titanium chloride catalysts; first-generation catalysts; cocatalysts; second-generation catalysts; catalysts morphology; and third-generation (supported catalysts). (JN)

  13. Diversified management of coal enterprises in China: model selection, motivation and effect analysis

    NASA Astrophysics Data System (ADS)

    Lyu, Jingye; Lian, Xu; Li, Penglin

    2018-01-01

    In the context of promoting the new energy revolution and economic development of the new normal, the coal industry to excess production capacity is one of the important aspects of structural reform of the supply side. The purpose of diversification of coal enterprises in China is to seize historical opportunities, create new models of development and improve operational efficiency. In the research on diversification of coal enterprises, exploring the mode selection, motivation and effect from the aspects of the industry is conducive to the realization of the smooth replacement and the sustainable development of enterprises, to further enrich the strategic management of coal enterprises, to provide effective reference for the formulation of enterprise management decision-making and implementation of diversification strategy.

  14. On issue of increasing profitability of automated energy technology complexes for preparation and combustion of water-coal suspensions

    NASA Astrophysics Data System (ADS)

    Brylina, O. G.; Osintsev, K. V.; Prikhodko, YU S.; Savosteenko, N. V.

    2018-03-01

    The article considers the issues of energy technological complexes economy increase on the existing techniques of water-coal suspensions preparation and burning basis due to application of highly effective control systems of electric drives and neurocontrol. The automated control system structure for the main boiler components is given. The electric drive structure is disclosed by the example of pumps (for transfer of coal-water mash and / or suspension). A system for controlling and diagnosing a heat and power complex based on a multi-zone regulator is proposed. The possibility of using neural networks for implementing the control algorithms outlined in the article is considered.

  15. Regenerable mixed copper-iron-inert support oxygen carriers for solid fuel chemical looping combustion process

    DOEpatents

    Siriwardane, Ranjani V.; Tian, Hanjing

    2016-12-20

    The disclosure provides an oxygen carrier for a chemical looping cycle, such as the chemical looping combustion of solid carbonaceous fuels, such as coal, coke, coal and biomass char, and the like. The oxygen carrier is comprised of at least 24 weight % (wt %) CuO, at least 10 wt % Fe2O3, and an inert support, and is typically a calcine. The oxygen carrier exhibits a CuO crystalline structure and an absence of iron oxide crystalline structures under XRD crystallography, and provides an improved and sustained combustion reactivity in the temperature range of 600.degree. C.-1000.degree. C. particularly for solid fuels such as carbon and coal.

  16. Structural specificity of chloroquine-hematin binding related to inhibition of hematin polymerization and parasite growth.

    PubMed

    Vippagunta, S R; Dorn, A; Matile, H; Bhattacharjee, A K; Karle, J M; Ellis, W Y; Ridley, R G; Vennerstrom, J L

    1999-11-04

    Considerable data now support the hypothesis that chloroquine (CQ)-hematin binding in the parasite food vacuole leads to inhibition of hematin polymerization and parasite death by hematin poisoning. To better understand the structural specificity of CQ-hematin binding, 13 CQ analogues were chosen and their hematin binding affinity, inhibition of hematin polymerization, and inhibition of parasite growth were measured. As determined by isothermal titration calorimetry (ITC), the stoichiometry data and exothermic binding enthalpies indicated that, like CQ, these analogues bind to two or more hematin mu-oxo dimers in a cofacial pi-pi sandwich-type complex. Association constants (K(a)'s) ranged from 0.46 to 2.9 x 10(5) M(-1) compared to 4.0 x 10(5) M(-1) for CQ. Remarkably, we were not able to measure any significant interaction between hematin mu-oxo dimer and 11, the 6-chloro analogue of CQ. This result indicates that the 7-chloro substituent in CQ is a critical structural determinant in its binding affinity to hematin mu-oxo dimer. Molecular modeling experiments reinforce the view that the enthalpically favorable pi-pi interaction observed in the CQ-hematin mu-oxo dimer complex derives from a favorable alignment of the out-of-plane pi-electron density in CQ and hematin mu-oxo dimer at the points of intermolecular contact. For 4-aminoquinolines related to CQ, our data suggest that electron-withdrawing functional groups at the 7-position of the quinoline ring are required for activity against both hematin polymerization and parasite growth and that chlorine substitution at position 7 is optimal. Our results also confirm that the CQ diaminoalkyl side chain, especially the aliphatic tertiary nitrogen atom, is an important structural determinant in CQ drug resistance. For CQ analogues 1-13, the lack of correlation between K(a) and hematin polymerization IC(50) values suggests that other properties of the CQ-hematin mu-oxo dimer complex, rather than its association constant alone, play a role in the inhibition of hematin polymerization. However, there was a modest correlation between inhibition of hematin polymerization and inhibition of parasite growth when hematin polymerization IC(50) values were normalized for hematin mu-oxo dimer binding affinities, adding further evidence that antimalarial 4-aminoquinolines act by this mechanism.

  17. Effect of carbon entrapped in Co-Al double oxides on structural restacking and electrochemical performances

    NASA Astrophysics Data System (ADS)

    Su, Ling-Hao; Zhang, Xiao-Gang

    Co-Al layered double hydroxides (LDH) were synthesized from nitrates and sodium benzoate by direct coprecipitation, and heated at 600 °C for 3 h in argon gas flow to obtain Co-Al double oxides. The effect of carbon, created during the pyrolysis of benzoate and inserted in resulting double oxides, on structural reconstruction was investigated by X-ray diffraction, scanning electron microscope, Raman spectroscopy, and infrared spectroscopy techniques. It is horizontal arrangement rather than vertical dilayer orientation in the interlayer spacing that was adopted by benzoate. An abnormal phenomenon was found that when immersed in aqueous 6 M KOH solution in air, the double oxides restacked to Co-Al layered double hydroxides with more regular crystal than before. The reason is believed that carbon was confined in the matrix of resulting double oxides, which prevented further collapse of the layered structure. Cyclic voltammetries (CV) and constant current charge/discharge measurements reveal that the restacked Co-Al layered double hydroxide has good long-life capacitive performance with a capacitance up to 145 F g -1 even at a large current of 2 A g -1. In addition, two clear slopes in chronoampermetric test demonstrated two different diffusion coefficients, explaining the slope of about 118.4 mV in the plot of formal potential E f versus pOH.

  18. Combustion and gasification characteristics of chars from four commercially significant coals of different rank. Final report

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Nsakala, N.Y.; Patel, R.L.; Lao, T.C.

    1982-09-01

    The combustion and gasification kinetics of four size graded coal chars were investigated experimentally in Combustion Engineering's Drop Tube Furnace System (DTFS). The chars were prepared in the DTFS from commercially significant coals representing a wide range of rank; these included a Pittsburgh No. 8 Seam hvAb coal, an Illinois No. 6 Seam hvCb coal, a Wyoming Sub C, and a Texas Lignite A. Additionally, a number of standard ASTM and special bench scale tests were performed on the coals and chars to characterize their physicochemical properties. Results showed that the lower rank coal chars were more reactive than themore » higher rank coal chars and that combustion reactions of chars were much faster than the corresponding gasification reactions. Fuel properties, temperature, and reactant gas partial pressure had a significant influence on both combustion and gasification, and particle size had a mild but discernible influence on gasification. Fuel reactivities were closely related to pore structure. Computer simulation of the combustion and gasification performances of the subject samples in the DTFS supported the experimental findings.« less

  19. Progress of fossil fuel science

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Demirbas, M.F.

    2007-07-01

    Coal is the most abundant and widely distributed fossil fuel. More than 45% of the world's electricity is generated from coal, and it is the major fuel for generating electricity worldwide. The known coal reserves in the world are enough for more than 215 years of consumption, while the known oil reserves are only about 39 times of the world's consumption and the known natural gas reserves are about 63 times of the world's consumption level in 1998. In recent years, there have been effective scientific investigations on Turkish fossil fuels, which are considerable focused on coal resources. Coal ismore » a major fossil fuel source for Turkey. Turkish coal consumption has been stable over the past decade and currently accounts for about 24% of the country's total energy consumption. Lignite coal has had the biggest share in total fossil fuel production, at 43%, in Turkey. Turkish researchers may investigate ten broad pathways of coal species upgrading, such as desulfurization and oxydesulfurization, pyrolysis and hydropyrolysis, liquefaction and hydroliquefaction, extraction and supercritical fluid extraction, gasification, oxidation, briquetting, flotation, and structure identification.« less

  20. Mechanised spraying device a novel technology for spraying fire protective coating material in the benches of opencast coal mines for preventing spontaneous combustion

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    R.V.K. Singh; V.K. Singh

    2004-10-15

    Spontaneous combustion in coal mines plays a vital role in occurrences of fire. Fire in coal, particularly in opencast mines, not only causes irreparable loss of national wealth but damages the surface structure and pollutes the environment. The problem of spontaneous combustion/fire in opencast coal benches is acute. Presently over 75% of the total production of coal in Indian mines is being carried out by opencast mining. Accordingly a mechanised spraying device has been developed for spraying the fire protective coating material for preventing spontaneous combustion in coal benches of opencast mines jointly by Central Mining Research Institute, Dhanbad andmore » M/s Signum Fire Protection (India) Pvt. Ltd., Nagpur under Science & Technology (S&T) project funded by Ministry of Coal, Govt. of India. The objective of this paper is to describe in detail about the mechanised spraying device and its application for spraying fire protective coating material in the benches of opencast coal mines for preventing spontaneous combustion/fire.« less

  1. Effects of coal storage in air on physical and chemical properties of coal and on gas adsorption

    USGS Publications Warehouse

    Mastalerz, Maria; Solano-Acosta, W.; Schimmelmann, A.; Drobniak, A.

    2009-01-01

    This paper investigates changes in the high-volatile bituminous Lower Block Coal Member from Indiana owing to moisture availability and oxidation in air at ambient pressure and temperature over storage time. Specifically, it investigates changes in chemistry, in surface area, and pore structure, as well as changes in methane and carbon dioxide adsorption capacities. Our results document that the methane adsorption capacity increased by 40%, whereas CO2 adsorption capacity increased by 18% during a 13-month time period. These changes in adsorption are accompanied by changes in chemistry and surface area of the coal. The observed changes in adsorption capacity indicate that special care must be taken when collecting samples and preserving coals until adsorption characteristics are measured in the laboratory. High-pressure isotherms from partially dried coal samples would likely cause overestimation of gas adsorption capacities, lead to a miscalculation of coal-bed methane prospects, and provide deceptively optimistic prognoses for recovery of coal-bed methane or capture of anthropogenic CO2. ?? 2009 Elsevier B.V. All rights reserved.

  2. Dynamics and Regulation of RecA Polymerization and De-Polymerization on Double-Stranded DNA

    PubMed Central

    Muniyappa, Kalappa; Yan, Jie

    2013-01-01

    The RecA filament formed on double-stranded (ds) DNA is proposed to be a functional state analogous to that generated during the process of DNA strand exchange. RecA polymerization and de-polymerization on dsDNA is governed by multiple physiological factors. However, a comprehensive understanding of how these factors regulate the processes of polymerization and de-polymerization of RecA filament on dsDNA is still evolving. Here, we investigate the effects of temperature, pH, tensile force, and DNA ends (in particular ssDNA overhang) on the polymerization and de-polymerization dynamics of the E. coli RecA filament at a single-molecule level. Our results identified the optimal conditions that permitted spontaneous RecA nucleation and polymerization, as well as conditions that could maintain the stability of a preformed RecA filament. Further examination at a nano-meter spatial resolution, by stretching short DNA constructs, revealed a striking dynamic RecA polymerization and de-polymerization induced saw-tooth pattern in DNA extension fluctuation. In addition, we show that RecA does not polymerize on S-DNA, a recently identified novel base-paired elongated DNA structure that was previously proposed to be a possible binding substrate for RecA. Overall, our studies have helped to resolve several previous single-molecule studies that reported contradictory and inconsistent results on RecA nucleation, polymerization and stability. Furthermore, our findings also provide insights into the regulatory mechanisms of RecA filament formation and stability in vivo. PMID:23825559

  3. Structural features of a bituminous coal and their changes during low-temperature oxidation and loss of volatiles investigated by advanced solid-state NMR spectroscopy

    USGS Publications Warehouse

    Mao, J.-D.; Schimmelmann, A.; Mastalerz, Maria; Hatcher, P.G.; Li, Y.

    2010-01-01

    Quantitative and advanced 13C solid-state NMR techniques were employed to investigate (i) the chemical structure of a high volatile bituminous coal, as well as (ii) chemical structural changes of this coal after evacuation of adsorbed gases, (iii) during oxidative air exposure at room temperature, and (iv) after oxidative heating in air at 75 ??C. The solid-state NMR techniques employed in this study included quantitative direct polarization/magic angle spinning (DP/MAS) at a high spinning speed of 14 kHz, cross polarization/total sideband suppression (CP/TOSS), dipolar dephasing, CH, CH2, and CHn selection, 13C chemical shift anisotropy (CSA) filtering, two-dimensional (2D) 1H-13C heteronuclear correlation NMR (HETCOR), and 2D HETCOR with 1H spin diffusion. With spectral editing techniques, we identified methyl CCH 3, rigid and mobile methylene CCH2C, methine CCH, quaternary Cq, aromatic CH, aromatic carbons bonded to alkyls, small-sized condensed aromatic moieties, and aromatic C-O groups. With direct polarization combined with spectral-editing techniques, we quantified 11 different types of functional groups. 1H-13C 2D HETCOR NMR experiments indicated spatial proximity of aromatic and alkyl moieties in cross-linked structures. The proton spin diffusion experiments indicated that the magnetization was not equilibrated at a 1H spin diffusion time of 5 ms. Therefore, the heterogeneity in spatial distribution of different functional groups should be above 2 nm. Recoupled C-H long-range dipolar dephasing showed that the fraction of large charcoal-like clusters of polycondensed aromatic rings was relatively small. The exposure of this coal to atmospheric oxygen at room temperature for 6 months did not result in obvious chemical structural changes of the coal, whereas heating at 75 ??C in air for 10 days led to oxidation of coal and generated some COO groups. Evacuation removed most volatiles and caused a significant reduction in aliphatic signals in its DP/MAS spectrum. DP/MAS, but not CP/MAS, allowed us to detect the changes during low-temperature oxidation and loss of volatiles. These results demonstrate the applicability of advanced solid-state NMR techniques in chemical characterization of coal. ?? 2010 American Chemical Society.

  4. Polymersome nanoreactors for enzymatic ring-opening polymerization.

    PubMed

    Nallani, Madhavan; de Hoog, Hans-Peter M; Cornelissen, Jeroen J L M; Palmans, Anja R A; van Hest, Jan C M; Nolte, Roeland J M

    2007-12-01

    Polystyrene-polyisocyanopeptide (PS-PIAT) polymersomes containing CALB in two different locations, one in the aqueous inner compartment and one in the bilayer, were investigated for enzymatic ring-opening polymerization of lactones in water. It is shown that the monomers 8-octanolactone and dodecalactone yield oligomers with this polymersome system. It is also observed that the polymerization activity is dependent on the position of the enzyme in the polymersome. SEM investigations show that the polymersome structures were destabilized during the polymerization. Further investigations show that the vesicular morphology of the polymersomes was destabilized only in the case of polymer product formation.

  5. Estimation and modeling of coal pore accessibility using small angle neutron scattering

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zhang, Rui; Liu, Shimin; Bahadur, Jitendra

    Gas diffusion in coal is controlled by nano-structure of the pores. The interconnectivity of pores not only determines the dynamics of gas transport in the coal matrix but also influences the mechanical strength. In this study, small angle neutron scattering (SANS) was employed to quantify pore accessibility for two coal samples, one of sub-bituminous rank and the other of anthracite rank. Moreover, a theoretical pore accessibility model was proposed based on scattering intensities under both vacuum and zero average contrast (ZAC) conditions. Our results show that scattering intensity decreases with increasing gas pressure using deuterated methane (CD 4) at lowmore » Q values for both coals. Pores smaller than 40 nm in radius are less accessible for anthracite than sub-bituminous coal. On the contrary, when the pore radius is larger than 40 nm, the pore accessibility of anthracite becomes larger than that of sub-bituminous coal. Only 20% of pores are accessible to CD 4 for anthracite and 37% for sub-bituminous coal, where the pore radius is 16 nm. For these two coals, pore accessibility and pore radius follows a power-law relationship.« less

  6. Estimation and modeling of coal pore accessibility using small angle neutron scattering

    DOE PAGES

    Zhang, Rui; Liu, Shimin; Bahadur, Jitendra; ...

    2015-09-04

    Gas diffusion in coal is controlled by nano-structure of the pores. The interconnectivity of pores not only determines the dynamics of gas transport in the coal matrix but also influences the mechanical strength. In this study, small angle neutron scattering (SANS) was employed to quantify pore accessibility for two coal samples, one of sub-bituminous rank and the other of anthracite rank. Moreover, a theoretical pore accessibility model was proposed based on scattering intensities under both vacuum and zero average contrast (ZAC) conditions. Our results show that scattering intensity decreases with increasing gas pressure using deuterated methane (CD 4) at lowmore » Q values for both coals. Pores smaller than 40 nm in radius are less accessible for anthracite than sub-bituminous coal. On the contrary, when the pore radius is larger than 40 nm, the pore accessibility of anthracite becomes larger than that of sub-bituminous coal. Only 20% of pores are accessible to CD 4 for anthracite and 37% for sub-bituminous coal, where the pore radius is 16 nm. For these two coals, pore accessibility and pore radius follows a power-law relationship.« less

  7. Sulfur determination in coal using molecular absorption in graphite filter vaporizer.

    PubMed

    Jim, Gibson; Katskov, Dmitri; Tittarelli, Paolo

    2011-02-15

    The vaporization of sulfur containing samples in graphite vaporizers for atomic absorption spectrometry is accompanied by modification of sulfur by carbon and, respectively, appearance at high temperature of structured molecular absorption in 200-210 nm wavelength range. It has been proposed to employ the spectrum for direct determination of sulfur in coal; soundness of the suggestion is evaluated by analysis of coal slurry using low resolution CCD spectrometer with continuum light source coupled to platform or filter furnace vaporizers. For coal in platform furnace losses of the analyte at low temperature and strong spectral background from the coal matrix hinder the determination. Both negative effects are significantly reduced in filter furnace, in which sample vapor efficiently interacts with carbon when transferred through the heated graphite filter. The method is verified by analysis of coals with sulfur content within 0.13-1.5% (m/m) range. The use of coal certified reference material for sulfur analyte addition to coal slurry permitted determination with random error 5-12%. Absolute and relative detection limits for sulfur in coal are 0.16 μg and 0.02 mass%, respectively. Copyright © 2010 Elsevier B.V. All rights reserved.

  8. Interactions of coal gangue and pine sawdust during combustion of their blends studied using differential thermogravimetric analysis.

    PubMed

    Zhang, Yuanyuan; Zhang, Zhezi; Zhu, Mingming; Cheng, Fangqin; Zhang, Dongke

    2016-08-01

    The interactions between coal gangue and pine sawdust during the combustion process were studied using thermogravimetric analysis. The effect of the blending ratio, oxygen concentration and heating rate on the weight loss (TG) and differential thermogravimetric (TGA) profiles was examined. The TG and DTG curves of the blends were not additives of those of the individual materials, suggesting that interactions between coal gangue and pine sawdust had occurred during the combustion, especially in the temperature range of 400-600°C. Kinetic analysis confirmed that the combustion of coal gangue, pine sawdust and their blends was chemical reaction controlled. Further analysis revealed that the interactions between coal gangue and pine sawdust were primarily due to thermal effects rather than structural changes, with the thermal inertia of coal gangue dominating over the behaviour of the blends. The interactions decreased with decreasing the coal gangue ratio in the blend, oxygen concentration and heating rate. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Analytical modeling of mercury injection in high-rank coalbed methane reservoirs based on pores and microfractures: a case study of the upper carboniferous Taiyuan Formation in the Heshun block of the Qinshui Basin, central China

    NASA Astrophysics Data System (ADS)

    Gu, Yang; Ding, Wenlong; Yin, Shuai; Wang, Ruyue; Mei, Yonggui; Liu, Jianjun

    2017-03-01

    The coalbed gas reservoirs in the Qinshui Basin in central China are highly heterogeneous; thus, the reservoir characteristics are difficult to assess. Research on the pore structure of a reservoir can provide a basis for understanding the occurrence and seepage mechanisms of coal reservoirs, rock physics modeling and the formulation of rational development plans. Therefore, the pore structure characteristics of the coalbed gas reservoirs in the high rank bituminous coal in the No. 15 coal seam of the Carboniferous Taiyuan Group in the Heshun coalbed methane (CBM) blocks in the northeastern Qinshui Basin were analyzed based on pressure mercury and scanning electron microscopy data. The results showed that the effective porosity system of the coal reservoir was mainly composed of pores and microfractures and that the pore throat configuration of the coal reservoir was composed of pores and microthroats. A model was developed based on the porosity and microfractures of the high rank coal rock and the mercury injection and drainage curves. The mercury injection curve model and the coal permeability are well correlated and were more reliable for the analysis of coal and rock pore system connectivity than the mercury drainage curve model. Coal rocks with developed microfractures are highly permeable; the production levels are often high during the initial drainage stages, but they decrease rapidly. A significant portion of the natural gas remains in the strata and cannot be exploited; therefore, the ultimate recovery is rather low. Coal samples with underdeveloped microfractures have lower permeabilities. While the initial production levels are lower, the production cycle is longer, and the ultimate recovery is higher. Therefore, the initial production levels of coal reservoirs with poorly developed microfractures in some regions of China may be low. However, over the long term, due to their higher ultimate recoveries and longer production cycles, the total gas production levels will increase. This understanding can provide an important reference for developing appropriate CBM development plans.

  10. Conducting Polymeric Hydrogel Electrolyte Based on Carboxymethylcellulose and Polyacrylamide/Polyaniline for Supercapacitor Applications

    NASA Astrophysics Data System (ADS)

    Suganya, N.; Jaisankar, V.; Sivakumar, E. K. T.

    Conducting polymer hydrogels represent a unique class of materials that possess enormous application in flexible electronic devices. In the present work, conducting carboxymethylcellulose (CMC)-co-polyacrylamide (PAAm)/polyaniline was synthesized by a two-step interpenetrating network solution polymerization technique. The synthesized CMC-co-PAAm/polyaniline with interpenetrating network structure was prepared by in situ polymerization of aniline to enhance conductivity. The molecular structure and morphology of the copolymer hydrogels were characterized by Fourier transform infrared spectroscopy and scanning electron microscopy. The novel conducting polymer hydrogels show good electrical and electrochemical behavior, which makes them potentially useful in electronic devices such as supercapacitors, biosensors, bioelectronics, solar cells and memory devices.

  11. Responsive polymer-based colloids for drug delivery and bioconversion

    NASA Astrophysics Data System (ADS)

    Kudina, Olena

    Responsive polymer-based colloids (RPBC) are the colloidal structures containing responsive polymeric component which is able to adapt its physico-chemical properties to the environment by undergoing chemical and/or conformational changes. The goal of the dissertation is to develop and characterize several groups of RPBC with different morphological complexity and explore their potential in drug delivery and bioconversion. The role of RPBC morphology for these specific applications is discussed in details. Three groups of RPBC were fabricated: i. polymeric micelles; ii. mixed polymeric micelles; iii. hybrid polymer-inorganic particles. All fabricated RPBCs contain polymeric component in their structure. The dissertation investigates how the changes of the responsive polymeric component properties are reflected in morphologies of RPBC. The first group of RPBC, polymeric micelles, was formed by the self-assembly of amphiphilic invertible polymers (AIPs) synthesized in our group. AIPs self-assemble into invertible micellar assemblies (IMAs) in solvents of different polarity. In this work, IMAs ability to invert the structure as a response to the change in solvent polarity was demonstrated using 1H NMR spectroscopy and SANS. It was shown that the IMAs incorporate hydrophobic cargo either in the core or in the shell, depending on the chemical structure of cargo molecules. Following in vitro study demonstrates that loaded with drug (curcumin) IMAs are cytotoxic to osteosarcoma cells. Mixed polymeric micelles represent another, more complex, RPBC morphologies studied in the dissertation. Mixed micelles were fabricated from AIPs and amphiphilic oligomers synthesized from pyromellitic dianhydride, polyethylene glycol methyl ethers, and alkanols/cholesterol. The combination of selected AIP and oligomers based on cholesterol results in mixed micelles with an increased drug-loading capacity (from 10% w/w loaded curcumin in single component IMAs to 26%w/w in mixed micelles). Even more complex colloids are hybrid polymer-inorganic particles, the third RPBC group studied in dissertation. Material was designed as core--shell particles with superparamagnetic core engulfed by grafted polymer brushes. These particles were loaded with enzymes (cellulases), thus, are turned into enzymogels for cellulose bioconversion. The study demonstrates that such RPBCs can be used multiple times during hydrolysis and provide an about four-fold increase in glucose production in comparison to free enzymes.

  12. Rate of coal hydroliquefaction: correlation to coal structure. Final report

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Baldwin, R.M.; Voorhees, K.J.; Durfee, S.L.

    This report summarizes the research carried out on DOE grant No. FG22-83PC60784. The work was divided into two phases. The first phase consisted of a series of coal liquefaction rate measurements on seven different coals from the Exxon sample bank, followed by correlation with parent coal properties. The second phase involved characterization of the coals by pyrolysis/mass spectrometry and subsequent correlations of the Py/MS patterns with various liquefaction reactivity parameters. The hydroliquefaction reactivities for a suite of 7 bituminous and subbituminous coals were determined on a kinetic basis. These reactivities were correlated fairly successfully with the following parent coal properties:more » volatile matter, H/C and O/C ratios, vitrinite reflectance, and calorific value. The total surface areas of the coals were experimentally determined. Reactivity was shown to be independent of surface area. Following completion of the batch reactor experiments, the seven coals investigated were analyzed by pyrolysis/mass spectrometry. The pyrolysis spectra were then submitted to factor analysis in order to extract significant features of the coal for use in correlational efforts. These factors were then related to a variety of liquefaction reactivity definitions, including both rate and extent of liquefaction to solvent solubility classifications (oils, asphaltenes, preasphaltenes, etc.). In general, extent of reaction was found to correlate best with the Py/MS data. 37 refs., 25 figs., 11 tabs.« less

  13. Electrical condition monitoring method for polymers

    DOEpatents

    Watkins, Jr., Kenneth S.; Morris, Shelby J [Hampton, VA; Masakowski, Daniel D [Worcester, MA; Wong, Ching Ping [Duluth, GA; Luo, Shijian [Boise, ID

    2008-08-19

    An electrical condition monitoring method utilizes measurement of electrical resistivity of an age sensor made of a conductive matrix or composite disposed in a polymeric structure such as an electrical cable. The conductive matrix comprises a base polymer and conductive filler. The method includes communicating the resistivity to a measuring instrument and correlating resistivity of the conductive matrix of the polymeric structure with resistivity of an accelerated-aged conductive composite.

  14. The research of distributed interactive simulation based on HLA in coal mine industry inherent safety

    NASA Astrophysics Data System (ADS)

    Dou, Zhi-Wu

    2010-08-01

    To solve the inherent safety problem puzzling the coal mining industry, analyzing the characteristic and the application of distributed interactive simulation based on high level architecture (DIS/HLA), a new method is proposed for developing coal mining industry inherent safety distributed interactive simulation adopting HLA technology. Researching the function and structure of the system, a simple coal mining industry inherent safety is modeled with HLA, the FOM and SOM are developed, and the math models are suggested. The results of the instance research show that HLA plays an important role in developing distributed interactive simulation of complicated distributed system and the method is valid to solve the problem puzzling coal mining industry. To the coal mining industry, the conclusions show that the simulation system with HLA plays an important role to identify the source of hazard, to make the measure for accident, and to improve the level of management.

  15. Management of local economic and ecological system of coal processing company

    NASA Astrophysics Data System (ADS)

    Kiseleva, T. V.; Mikhailov, V. G.; Karasev, V. A.

    2016-10-01

    The management issues of local ecological and economic system of coal processing company - coal processing plant - are considered in the article. The objectives of the research are the identification and the analysis of local ecological and economic system (coal processing company) performance and the proposals for improving the mechanism to support the management decision aimed at improving its environmental safety. The data on the structure of run-of-mine coal processing products are shown. The analysis of main ecological and economic indicators of coal processing enterprises, characterizing the state of its environmental safety, is done. The main result of the study is the development of proposals to improve the efficiency of local enterprise ecological and economic system management, including technical, technological and business measures. The results of the study can be recommended to industrial enterprises to improve their ecological and economic efficiency.

  16. L-Lactide Ring-Opening Polymerization with Tris(acetylacetonate)Titanium(IV) for Renewable Material.

    PubMed

    Kim, Da Hee; Yoo, Ji Yun; Ko, Young Soo

    2016-05-01

    A new Ti-type of catalyst for L-lactide polymerization was synthesized by reaction of titanium(IV) isopropoxide (TTIP) with acetylacetone (AA). Moreover, PLA was prepared by the bulk ring-opening polymerization using synthesized Ti catalyst. Polymerization behaviors were examined depending on monomer/catalyst molar ratio, polymerization temperature and time. The structure of synthesized catalysts was verified with FT-IR and 1H NMR and the properties of poly(L-lactide) (PLLA) were examined by GPC, DSC and FT-IR. There existed about 30 minutes of induction time at the monomer/catalyst molar ratio of 300. The molecular weight (MW) increased as monomer/catalyst molar ratio increased. The MW increased almost linearly as polymerization progressed. Increasing polymerization temperature increased the molecular weight of PLLA as well as monomer/catalyst molar ratio. The melting point (T(m)) of polymers was in the range of 142 to 167 degrees C. Lower T(m) was expected to be resulted from relatively lower molecular weight.

  17. Assessment on the Benefits from Energy Structure Optimization and Coal-fired Emission Control in Beijing: 1998-2013

    NASA Astrophysics Data System (ADS)

    Zong, Y.; He, K.; Zhang, Q.; Hong, C.

    2016-12-01

    Coal has long been an important energy type of Beijing's energy consumption. Since 1998, to improve urban air quality, Beijing has vigorously promoted the structure optimization of energy consumption. Primary measures included the implementation of strict emission standards for coal-fired power plant boilers, subsidized replacement and after-treatment retrofit of coal-fired boilers, the mandatory application of low-sulfur coal, and the accelerated use of natural gas, imported electricity and other clean energy. This work attempts to assess the emission reduction benefits on measures of three sectors, including replacing with clean energy and application of end-of-pipe control technologies in power plants, comprehensive control on coal-fired boilers and residential heating renovation. This study employs the model of Multi-resolution Emission Inventory for China (MEIC) to quantify emission reductions from upfront measures. These control measures have effectively reduced local emissions of major air pollutants in Beijing. The total emissions of PM2.5, PM10, SO2 and NOX from power plants in Beijing are estimated to have reduced 14.5 kt, 23.7 kt, 45.0 kt and 7.6 kt from 1998 to 2013, representing reductions of 86%, 87%, 85% and 16%, respectively. Totally, 14.3 kt, 24.0 kt, 136 kt and 48.7kt of PM2.5, PM10, SO2 and NOX emissions have been mitigated due to the comprehensive control measures on coal-fired boilers from 1998 to 2013. Residential heating renovation projects by replacing coal with electricity in Beijing's conventional old house areas contribute to emission reductions of 630 t, 870 t, 2070 t and 790 t for PM2.5, PM10, SO2 and NOX, respectively.

  18. A combined interfacial and in-situ polymerization strategy to construct well-defined core-shell epoxy-containing SiO2-based microcapsules with high encapsulation loading, super thermal stability and nonpolar solvent tolerance

    NASA Astrophysics Data System (ADS)

    Jia; Wang; Tian; Li; Xu; Jiao; Cao; Wu

    2016-10-01

    SiO2-based microcapsules containing hydrophobic molecules exhibited potential applications such as extrinsic self-healing, drug delivery, due to outstanding thermal and chemical stability of SiO2. However, to construct SiO2-based microcapsules with both high encapsulation loading and long-term structural stability is still a troublesome issue, limiting their further utilization. We herein design a single-batch route, a combined interfacial and in-situ polymerization strategy, to fabricate epoxy-containing SiO2-based microcapsules with both high encapsulation loading and long-term structural stability. The final SiO2-based microcapsules preserve high encapsulation loading of 85.7 wt% by controlling exclusively hydrolysis and condensed polymerization at oil/water interface in the initial interfacial polymerization step. In the subsequent in-situ polymerization step, the initial SiO2-based microcapsules as seeds could efficiently harvest SiO2 precursors and primary SiO2 particles to finely tune the SiO2 wall thickness, thereby enhancing long-term structural stability of the final SiO2-based microcapsules including high thermal stability with almost no any weight loss until 250°C, and strong tolerance against nonpolar solvents such as CCl4 with almost unchanged core-shell structure and unchanged core weight after immersing into strong solvents for up to 5 days. These SiO2-based microcapsules are extremely suited for processing them into anticorrosive coating in the presence of nonpolar solvents for self-healing application.

  19. Silicone-containing aqueous polymer dispersions with hybrid particle structure.

    PubMed

    Kozakiewicz, Janusz; Ofat, Izabela; Trzaskowska, Joanna

    2015-09-01

    In this paper the synthesis, characterization and application of silicone-containing aqueous polymer dispersions (APD) with hybrid particle structure are reviewed based on available literature data. Advantages of synthesis of dispersions with hybrid particle structure over blending of individual dispersions are pointed out. Three main processes leading to silicone-containing hybrid APD are identified and described in detail: (1) emulsion polymerization of organic unsaturated monomers in aqueous dispersions of silicone polymers or copolymers, (2) emulsion copolymerization of unsaturated organic monomers with alkoxysilanes or polysiloxanes with unsaturated functionality and (3) emulsion polymerization of alkoxysilanes (in particular with unsaturated functionality) and/or cyclic siloxanes in organic polymer dispersions. The effect of various factors on the properties of such hybrid APD and films as well as on hybrid particles composition and morphology is presented. It is shown that core-shell morphology where silicones constitute either the core or the shell is predominant in hybrid particles. Main applications of silicone-containing hybrid APD and related hybrid particles are reviewed including (1) coatings which show specific surface properties such as enhanced water repellency or antisoiling or antigraffiti properties due to migration of silicone to the surface, and (2) impact modifiers for thermoplastics and thermosets. Other processes in which silicone-containing particles with hybrid structure can be obtained (miniemulsion polymerization, polymerization in non-aqueous media, hybridization of organic polymer and polysiloxane, emulsion polymerization of silicone monomers in silicone polymer dispersions and physical methods) are also discussed. Prospects for further developments in the area of silicone-containing hybrid APD and related hybrid particles are presented. Copyright © 2015. Published by Elsevier B.V.

  20. Design and fabrication of advanced materials from Illinois coal wastes. Quarterly report, 1 December 1994--28 February 1995

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Malhotra, V.M.; Wright, M.A.

    1995-12-31

    The main goal of this project is to develop a bench-scale procedure to design and fabricate advanced brake and structural composite materials from Illinois coal combustion residues. During the first two quarters of the project, the thrust of the work directed towards characterizing the various coal combustion residues and FGD residue, i.e., scrubber sludge. Scanning electron microscopy (SEM), differential scanning calorimetry (DSC), differential thermal analysis (DTA), and transmission-Fourier transform infrared (FTIR) were conducted on PCC fly ash (Baldwin), FBC fly ash (ADK unit l-6), FBC fly ash (S.I. coal), FBC spent bed ash (ADM, unit l-6), bottom ash, and scrubbermore » sludge (CWLP) residues to characterize their geometrical shapes, mineral phases, and thermal stability. Our spectroscopic results indicate that the scrubber sludge is mainly composed of a gypsum-like phase whose lattice structure is different from the lattice structure of conventional gypsum, and sludge does not contain hannebachite (CaSO{sub 3}.0.5H{sub 2}O) phase. Our attempts to fabricate brake frictional shoes, in the form of 1.25 inch disks, from PCC fly ash, FBC spent bed ash, scrubber sludge, coal char, iron particles, and coal tar were successful. Based on the experience gained and microscopic analyses, we have now upscaled our procedures to fabricate 2.5 inch diameter disk,- from coal combustion residues. This has been achieved. The SEM and Young`s modulus analyses of brake composites fabricated at 400 psi < Pressure < 2200 psi suggest pressure has a strong influence on the particle packing and the filling of interstices in our composites. Also, these results along with mechanical behavior of the fabricated disks lead us to believe that the combination of surface altered PCC fly ash and scrubber sludge particles, together ed ash particles are ideal for our composite materials.« less

  1. SOM neural network fault diagnosis method of polymerization kettle equipment optimized by improved PSO algorithm.

    PubMed

    Wang, Jie-sheng; Li, Shu-xia; Gao, Jie

    2014-01-01

    For meeting the real-time fault diagnosis and the optimization monitoring requirements of the polymerization kettle in the polyvinyl chloride resin (PVC) production process, a fault diagnosis strategy based on the self-organizing map (SOM) neural network is proposed. Firstly, a mapping between the polymerization process data and the fault pattern is established by analyzing the production technology of polymerization kettle equipment. The particle swarm optimization (PSO) algorithm with a new dynamical adjustment method of inertial weights is adopted to optimize the structural parameters of SOM neural network. The fault pattern classification of the polymerization kettle equipment is to realize the nonlinear mapping from symptom set to fault set according to the given symptom set. Finally, the simulation experiments of fault diagnosis are conducted by combining with the industrial on-site historical data of the polymerization kettle and the simulation results show that the proposed PSO-SOM fault diagnosis strategy is effective.

  2. Dual drug release from hydrogels covalently containing polymeric micelles that possess different drug release properties.

    PubMed

    Murata, Mari; Uchida, Yusuke; Takami, Taku; Ito, Tomoki; Anzai, Ryosuke; Sonotaki, Seiichi; Murakami, Yoshihiko

    2017-05-01

    In the present study, we designed hydrogels for dual drug release: the hydrogels that covalently contained the polymeric micelles that possess different drug release properties. The hydrogels that were formed from polymeric micelles possessing a tightly packed (i.e., well-entangled) inner core exhibited a higher storage modulus than the hydrogels that were formed from the polymeric micelles possessing a loosely packed structure. Furthermore, we conducted release experiments and fluorescent observations to evaluate the profiles depicting the release of two compounds, rhodamine B and auramine O, from either polymeric micelles or hydrogels. According to our results, (1) hydrogels that covalently contains polymeric micelles that possess different drug release properties successfully exhibit the independent release behaviors of the two compounds and (2) fluorescence microscopy can greatly facilitate efforts to evaluate drug release properties of materials. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Cooperative polymerization of α-helices induced by macromolecular architecture

    NASA Astrophysics Data System (ADS)

    Baumgartner, Ryan; Fu, Hailin; Song, Ziyuan; Lin, Yao; Cheng, Jianjun

    2017-07-01

    Catalysis observed in enzymatic processes and protein polymerizations often relies on the use of supramolecular interactions and the organization of functional elements in order to gain control over the spatial and temporal elements of fundamental cellular processes. Harnessing these cooperative interactions to catalyse reactions in synthetic systems, however, remains challenging due to the difficulty in creating structurally controlled macromolecules. Here, we report a polypeptide-based macromolecule with spatially organized α-helices that can catalyse its own formation. The system consists of a linear polymeric scaffold containing a high density of initiating groups from which polypeptides are grown, forming a brush polymer. The folding of polypeptide side chains into α-helices dramatically enhances the polymerization rate due to cooperative interactions of macrodipoles between neighbouring α-helices. The parameters that affect the rate are elucidated by a two-stage kinetic model using principles from nucleation-controlled protein polymerizations; the key difference being the irreversible nature of this polymerization.

  4. [Effects of biochar application on the abundance and structure of ammonia-oxidizer communities in coal-mining area.

    PubMed

    Liu, Yuan; Zhu, Ji Rong; Wu, Yu Chen; Shu, Liang Zuo

    2017-10-01

    As a new type of soil amendment, biochar can effectively improve soil fertility, structure and soil nitrogen transformation. We studied the effects of biochar application on soil properties, abundance and community structure of ammonia oxidizer in coal-mining area. The results showed that the biochar application significantly increased contents of soil NH4+-N, total nitrogen, available phosphorus and potassium. Compared with the control, no change in the abundance of ammonia-oxidizing archaea (AOA) was found under biochar treatment, but there was a significant increase in the abundance of ammonia-oxidizing bacteria (AOB). The analysis of T-RFLP profiles showed that biochar significantly increased the diversity indexes of AOA and AOB, and altered the community structure of both AOA and AOB. Improved soil nutrients as well as increased abundance and diversity of ammonia-oxidizing community to some extent indicated the potential of biochar application in reclamation of coal-mining area soil.

  5. Raising quality of maintenance and control of metallic structures in large-load technological machines

    NASA Astrophysics Data System (ADS)

    Drygin, M. Yu; Kuryshkin, N. P.

    2018-01-01

    Active growth of coal extraction and underinvestment of coal mining in Russia lead to the fact that technical state of more than 86% of technological machines at opencast coal mines is unacceptable. One of the most significant problems is unacceptable state of supporting metallic structures of excavators and mine dump trucks. The analysis has shown that defects in these metallic structures had been accumulated for a long time. Their removal by the existing method of repair welding was not effective - the flaws reappeared in 2-6 months of technological machines’ service. The authors detected the prime causes that did not allow to make a good repair welding joint. A new technology of repair welding had been tested and endorsed, and this allowed to reduce the number of welded joints’ flaws by 85% without additional raising welders’ qualification. As a result the number of flaws in metallic structures of the equipment had been reduced by 35 % as early as in the first year of using the new technology.

  6. Study on the characteristics of coal rock electromagnetic radiation (EMR) and the main influencing factors

    NASA Astrophysics Data System (ADS)

    Song, Xiaoyan; Li, Xuelong; Li, Zhonghui; Zhang, Zhibo; Cheng, Fuqi; Chen, Peng; Liu, Yongjie

    2018-01-01

    Coal rock would produce electromagnetic radiation (EMR) in the loading process, but study on the influence factors influence on the coal rock EMR characteristics in the mesoscopic level is not insufficient. In the paper, the EMR characteristics of coal and rock samples under uniaxial loading are studied. Several typical microcosmic mechanisms affecting the characteristics of EMR are discussed, such as strength, composition and microstructure of the samples. Results show that the macroscopic structure of the outburst coal is soft, the corresponding EMR signal increases slowly with the loading increase and the EMR peak is smaller. The rockburst coal has a strong brittleness, the EMR signal increases quickly and EMR peak appears while the coal breaks is larger than the outburst coal. The EMR characteristics of rock samples are similar to the rockburst coal, but the EMR peak is the largest. When the coal rock microstructure is complete, the coal rock block is larger and the brittleness is stronger, then the corresponding strength would be larger. And the free charge generated by thermal excitation, field emission and intergranular chemical bond breakage would also be more. In the meantime, the crack propagation rate becomes greater, therefore the EMR is more stronger. The piezoelectric effect is mainly caused by the linear elastic stage of the specimen deformation and rupture, which contributes less to the EMR signals. This study is of great theoretical and practical value for assessing the mechanical state of coal rock through EMR technology, and accurately monitoring and predicting the coal rock dynamic disasters.

  7. Dissolved Divalent Metal and pH Effects on Amino Acid Polymerization: A Thermodynamic Evaluation.

    PubMed

    Kitadai, Norio

    2017-03-01

    Polymerization of amino acids is a fundamentally important step for the chemical evolution of life. Nevertheless, its response to changing environmental conditions has not yet been well understood because of the lack of reliable quantitative information. For thermodynamics, detailed prediction over diverse combinations of temperature and pH has been made only for a few amino acid-peptide systems. This study used recently reported thermodynamic dataset for the polymerization of the simplest amino acid "glycine (Gly)" to its short peptides (di-glycine and tri-glycine) to examine chemical and structural characteristics of amino acids and peptides that control the temperature and pH dependence of polymerization. Results showed that the dependency is strongly controlled by the intramolecular distance between the amino and carboxyl groups in an amino acid structure, although the side-chain group role is minor. The polymerization behavior of Gly reported earlier in the literature is therefore expected to be a typical feature for those of α-amino acids. Equilibrium calculations were conducted to examine effects of dissolved metals as a function of pH on the monomer-polymer equilibria of Gly. Results showed that metals shift the equilibria toward the monomer side, particularly at neutral and alkaline pH. Metals that form weak interaction with Gly (e.g., Mg 2+ ) have no noticeable influence on the polymerization, although strong interaction engenders significant decrease of the equilibrium concentrations of Gly peptides. Considering chemical and structural characteristics of Gly and Gly peptides that control their interactions with metals, it can be expected that similar responses to the addition of metals are applicable in the polymerization of neutral α-amino acids. Neutral and alkaline aqueous environments with dissolved metals having high affinity with neutral α-amino acids (e.g., Cu 2+ ) are therefore not beneficial places for peptide bond formation on the primitive Earth.

  8. Characterization of Malaysian coals for carbon dioxide sequestration

    NASA Astrophysics Data System (ADS)

    Abunowara, M.; Bustam, M. A.; Sufian, S.; Eldemerdash, U.

    2016-06-01

    Coal samples from Mukah-Balingian and Merit-Pila coal mines were characterized with ultimate, approximate, petrographic analysis, FT-IR spectra patterns, FESEM images and BET measurements to obtain information on the chemical composition and chemical structure in the samples. Two coal samples were obtained from Merit-Pila coal mine namely sample1 (S1) and sample2 (S2). The other two coal samples were obtained from Mukah-Balingian coal mine namely sample3 (S3) and sample4 (S4), Sarawak, Malaysia. The results of ultimate analysis show that coal S1 has the highest carbon percentage by 54.47%, the highest hydrogen percentage by 10.56% and the lowest sulfur percentage by 0.19% and the coal S4 has the highest moisture content by 31.5%. The coal S1 has the highest fixed carbon percentage by 42.6%. The coal S4 has BET surface area by 2.39 m2/g and Langmuir surface area by 3.0684 m2/g respectively. Fourier-Transform Infrared (FT-IR) spectroscopy analysis of all coal samples shows a presence of oxygen containing functional groups which considered are as active sites on coal surface. The oxygen functional groups are mainly carboxyl (-COOH), hydroxyl (-OH), alkyl (-CH, -CH2, -CH3), aliphatic (C-O-C stretching associated with -OH), amino (-NH stretching vibrations), (-NH stretching vibrations), aromatic (C=C), vinylic (C=C) and clay minerals. In all FE-SEM images of coal samples matrix, it can be seen that there are luminous and as non luminous features which refer to the existence of various minerals types distributed in the coal organic matrix. The bright luminosity is due to the presence of sodium, potassium or aluminium. According to petrographic analysis, all coal sample samples are range in vitrinite reflectance from 0.38% to 56% (VRr) are sub-bituminous coals.

  9. Analysis 320 coal mine accidents using structural equation modeling with unsafe conditions of the rules and regulations as exogenous variables.

    PubMed

    Zhang, Yingyu; Shao, Wei; Zhang, Mengjia; Li, Hejun; Yin, Shijiu; Xu, Yingjun

    2016-07-01

    Mining has been historically considered as a naturally high-risk industry worldwide. Deaths caused by coal mine accidents are more than the sum of all other accidents in China. Statistics of 320 coal mine accidents in Shandong province show that all accidents contain indicators of "unsafe conditions of the rules and regulations" with a frequency of 1590, accounting for 74.3% of the total frequency of 2140. "Unsafe behaviors of the operator" is another important contributory factor, which mainly includes "operator error" and "venturing into dangerous places." A systems analysis approach was applied by using structural equation modeling (SEM) to examine the interactions between the contributory factors of coal mine accidents. The analysis of results leads to three conclusions. (i) "Unsafe conditions of the rules and regulations," affect the "unsafe behaviors of the operator," "unsafe conditions of the equipment," and "unsafe conditions of the environment." (ii) The three influencing factors of coal mine accidents (with the frequency of effect relation in descending order) are "lack of safety education and training," "rules and regulations of safety production responsibility," and "rules and regulations of supervision and inspection." (iii) The three influenced factors (with the frequency in descending order) of coal mine accidents are "venturing into dangerous places," "poor workplace environment," and "operator error." Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. Visualizing polynucleotide polymerase machines at work

    PubMed Central

    Steitz, Thomas A

    2006-01-01

    The structures of T7 RNA polymerase (T7 RNAP) captured in the initiation and elongation phases of transcription, that of φ29 DNA polymerase bound to a primer protein and those of the multisubunit RNAPs bound to initiating factors provide insights into how these proteins can initiate RNA synthesis and synthesize 6–10 nucleotides while remaining bound to the site of initiation. Structural insight into the translocation of the product transcript and the separation of the downstream duplex DNA is provided by the structures of the four states of nucleotide incorporation. Single molecule and biochemical studies show a distribution of primer terminus positions that is altered by the binding of NTP and PPi ligands. This article reviews the insights that imaging the structure of polynucleotide polymerases at different steps of the polymerization reaction has provided on the mechanisms of the polymerization reaction. Movies are shown that allow the direct visualization of the conformational changes that the polymerases undergo during the different steps of polymerization. PMID:16900098

  11. Effects of annealing temperature on structure and magnetic properties of CoAl0.2Fe1.8O4/SiO2 nanocomposites

    NASA Astrophysics Data System (ADS)

    Wang, L.; Li, J.; Liu, M.; Zhang, Y. M.; Lu, J. B.; Li, H. B.

    2012-12-01

    CoAl0.2Fe1.8O4/SiO2 nanocomposites were prepared by sol-gel method. The effects of annealing temperature on the structure and magnetic properties of the samples were studied by X-ray diffraction, transmission electron microscopy, vibrating sample magnetometer and Mössbauer spectroscopy. The results show that the CoAl0.2Fe1.8O4 in the samples exhibits a spinel structure after being annealed. As annealing temperature increases from 800 to 1200 °C, the average grain size of CoAl0.2Fe1.8O4 in the nanocomposites increases from 5 to 41 nm while the lattice constant decreases from 0.8397 to 0.8391 nm, the saturation magnetization increases from 21.96 to 41.53 emu/g. Coercivity reaches a maximum of 1082 Oe for the sample annealed at 1100 °C, and thereafter decreases with further increasing annealing temperature. Mössbauer spectra show that the isomer shift decreases, hyperfine field increases and the samples transfer from mixed state of superparamagnetic and magnetic order to the completely magnetic order with annealing temperature increasing from 800 to 1200 °C.

  12. Low-moment ferrimagnetic phase of the Heusler compound Cr2CoAl

    NASA Astrophysics Data System (ADS)

    Jamer, Michelle E.; Marshall, Luke G.; Sterbinsky, George E.; Lewis, Laura H.; Heiman, Don

    2015-11-01

    Synthesizing half-metallic fully compensated ferrimagnets that form in the inverse Heusler phase could lead to superior spintronic devices. These materials would have high spin polarization at room temperature with very little fringing magnetic fields. Previous theoretical studies indicated that Cr2CoAl should form in a stable inverse Heusler lattice due to its low activation energy. Here, stoichiometric Cr2CoAl samples were arc-melted and annealed at varying temperatures, followed by studies of their structural and magnetic properties. High-resolution synchrotron X-ray diffraction revealed a chemically ordered Heusler phase in addition to CoAl and Cr phases. Soft X-ray magnetic circular dichroism revealed that the Cr and Co magnetic moments are antiferromagnetically oriented leading to the observed low magnetic moment in Cr2CoAl.

  13. Influence of The Metamorphism Grade and Porosity of Hard Coal on Sorption and Desorption of Propane / Wpływ Stopnia Metamorfizmu I Porowatości Węgli Kamiennych Na Sorpcję I Desorpcję Propanu

    NASA Astrophysics Data System (ADS)

    Dudzińska, Agnieszka; Żyła, Mieczysław; Cygankiewicz, Janusz

    2013-09-01

    In this paper results of investigations of sorption of hard coal samples collected from the extracted coal seams of Polish coal mines are presented. As sorbate propane was used. Examinations were carried out in the temperature of 298 K by means of volumetric assessment with the use of apparatus ASAP 2010 of Micromeritics. On the basis of conducted examinations it has been found out that the amount of sorbed propane depend on a type of coal, its metamorphism grade, content of oxygen element, moisture and porosity of these coals. The greatest amounts of propane are sorbed by low carbonized, high-porosity coals of high content of oxygen and moisture. Sorption of relatively high amounts of propane by these coals (ca. 10 cm3/g) is a result of the influence of polar surface of coals with molecules of propane and good availability of internal microporous structure of these coals for molecules of examined sorbate. Medium and high carbonized coals sorb insignificant amounts of propane. These coals have compact structure and non-polar character of their surface, their internal porous structure is to a minor degree available for propane molecules in conditions of carried out research. Sorption of propane in this case, takes place mainly in surface pores and on the surface of coals. Moreover, measurements of desorption isotherms of propane showing irreversible character of sorption were made. Desorption isotherms do not come together with sorption isotherms forming open hysteresis loop. Amounts of non-desorbing propane remaining in the coal depend on the type of examined coal. W pracy przedstawiono wyniki badań sorpcji próbek węgli kamiennych pobranych z eksploatowanych pokładów węglowych polskich kopalń. Jako sorbat zastosowano propan. Badania przeprowadzono w temperaturze 298 K metodą objętościową z wykorzystaniem aparatu ASAP 2010 firmy Micromeritics. Na podstawie przeprowadzonych badań stwierdzono, że ilości sorbowanego propanu są zależne od rodzaju węgla, jego stopnia metamorfizmu, zawartości pierwiastka tlenu, wilgoci i porowatości tych węgli. Największe ilości propanu sorbują węgle niskouwęglone, wysokoporowate o dużej zawartości tlenu i wilgoci. Sorpcja stosunkowo dużych ilości propanu tych węgli (ok. 10 cm3/g) jest wynikiem oddziaływania polarnej powierzchni węgli z cząsteczkami propanu oraz dobrej dostępności wewnętrznej mikroporowatej struktury tych węgli dla cząsteczek badanego sorbatu. Węgle średnio i wysokouwęglone sorbują niewielkie ilości propanu. Węgle te mają zwartą budowę oraz niepolarny charakter powierzchni, ich wewnętrzna struktura porowata jest w niewielkim stopniu dostępna dla cząsteczek propanu w warunkach przeprowadzanych badań. Sorpcja propanu w tym przypadku zachodzi głównie w powierzchniowych porach i na powierzchni węgli. Przeprowadzono również pomiary izoterm desorpcji propanu wykazując nieodwracalny charakter sorpcji. Izotermy desorpcji nie zbiegają się z izotermami sorpcji tworząc otwartą pętlę histerezy. Pozostające w węglu ilości nie desorbującego się propanu są zależne od rodzaju badanego węgla.

  14. Solid-State Metalized Reduction of Magnesium-Rich Low-Nickel Oxide Ores Using Coal as the Reductant Based on Thermodynamic Analysis

    NASA Astrophysics Data System (ADS)

    Ma, Baozhong; Xing, Peng; Yang, Weijiao; Wang, Chengyan; Chen, Yongqiang; Wang, Hua

    2017-08-01

    The solid-state metalized reduction of magnesium-rich low-nickel oxide ore using coal as a reductant was studied based on thermodynamic analysis. The major constituent minerals of the ore were silicates and goethite. The former was the main nickel-bearing mineral, and the latter was the main iron-bearing mineral. Single factor tests were conducted to investigate the effects of reduction temperature, duration, and coal dosage on the beneficiation of nickel and iron such that optimal conditions were achieved. Considering the low recoveries of nickel and iron (Ni, 13.9 pct; Fe, 30.3 pct) under the obtained optimal conditions, an improved process, adding CaF2 before the reaction, was proposed to modify the solid-state metalized process. The results showed that the recoveries of nickel and iron reached to 96.5 and 73.4 pct, respectively, and that the grades of nickel and iron in the concentrate increased from 2.5 and 62.6 wt pct to 6.9 and 71.4 wt pct, respectively. Nickel and iron in the absence of CaF2 were metalized; nevertheless, the size of ferronickel particles was only 1 μm. Furthermore, alloys in the presence of CaF2 aggregated and exhibited bands with a length greater than 200 µm. These observations suggested that CaF2 could effectively reduce the surface tension of the newly generated alloy interface and promote the migration and polymerization of the alloy particles, which improves the beneficiation of nickel and iron by magnetic separation.

  15. Bactericidal Specificity and Resistance Profile of Poly(Quaternary Ammonium) Polymers and Protein-Poly(Quaternary Ammonium) Conjugates.

    PubMed

    Ji, Weihang; Koepsel, Richard R; Murata, Hironobu; Zadan, Sawyer; Campbell, Alan S; Russell, Alan J

    2017-08-14

    Antibacterial polymers are potentially powerful biocides that can destroy bacteria on contact. Debate in the literature has surrounded the mechanism of action of polymeric biocides and the propensity for bacteria to develop resistance to them. There has been particular interest in whether surfaces with covalently coupled polymeric biocides have the same mechanism of action and resistance profile as similar soluble polymeric biocides. We designed and synthesized a series of poly(quaternary ammonium) polymers, with tailorable molecular structures and architectures, to engineer their antibacterial specificity and their ability to delay the development of bacterial resistance. These linear poly(quaternary ammonium) homopolymers and block copolymers, generated using atom transfer radical polymerization, had structure-dependent antibacterial specificity toward Gram positive and negative bacterial species. When single block copolymers contained two polymer segments of differing antibacterial specificity, the polymer combined the specificities of its two components. Nanoparticulate human serum albumin-poly(quaternary ammonium) conjugates of these same polymers, synthesized via "grafting from" atom transfer radical polymerization, were strongly biocidal and also exhibited a marked decrease in the rate of bacterial resistance development relative to linear polymers. These protein-biocide conjugates mimicked the behavior of surface-presented polycationic biocides rather than their nonproteinaceous counterparts.

  16. Adhesive F-actin Waves: A Novel Integrin-Mediated Adhesion Complex Coupled to Ventral Actin Polymerization

    PubMed Central

    Case, Lindsay B.; Waterman, Clare M.

    2011-01-01

    At the leading lamellipodium of migrating cells, protrusion of an Arp2/3-nucleated actin network is coupled to formation of integrin-based adhesions, suggesting that Arp2/3-mediated actin polymerization and integrin-dependent adhesion may be mechanistically linked. Arp2/3 also mediates actin polymerization in structures distinct from the lamellipodium, in “ventral F-actin waves” that propagate as spots and wavefronts along the ventral plasma membrane. Here we show that integrins engage the extracellular matrix downstream of ventral F-actin waves in several mammalian cell lines as well as in primary mouse embryonic fibroblasts. These “adhesive F-actin waves” require a cycle of integrin engagement and disengagement to the extracellular matrix for their formation and propagation, and exhibit morphometry and a hierarchical assembly and disassembly mechanism distinct from other integrin-containing structures. After Arp2/3-mediated actin polymerization, zyxin and VASP are co-recruited to adhesive F-actin waves, followed by paxillin and vinculin, and finally talin and integrin. Adhesive F-actin waves thus represent a previously uncharacterized integrin-based adhesion complex associated with Arp2/3-mediated actin polymerization. PMID:22069459

  17. Simultaneous covalent and noncovalent hybrid polymerizations

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Yu, Z.; Tantakitti, F.; Yu, T.

    Covalent and supramolecular polymers are two distinct forms of soft matter, composed of long chains of covalently and noncovalently linked structural units, respectively. We report a hybrid system formed by simultaneous covalent and supramolecular polymerizations of monomers. The process yields cylindrical fibers of uniform diameter that contain covalent and supramolecular compartments, a morphology not observed when the two polymers are formed independently. The covalent polymer has a rigid aromatic imine backbone with helicoidal conformation, and its alkylated peptide side chains are structurally identical to the monomer molecules of supramolecular polymers. In the hybrid system, covalent chains grow to higher averagemore » molar mass relative to chains formed via the same polymerization in the absence of a supramolecular compartment. The supramolecular compartments can be reversibly removed and re-formed to reconstitute the hybrid structure, suggesting soft materials with novel delivery or repair functions.« less

  18. Visible-Light Initiated Free-Radical/Cationic Ring-Opening Hybrid Photopolymerization of Methacrylate/Epoxy: Polymerization Kinetics, Crosslinking Structure, and Dynamic Mechanical Properties.

    PubMed

    Ge, Xueping; Ye, Qiang; Song, Linyong; Misra, Anil; Spencer, Paulette

    2015-04-01

    The effects of polymerization kinetics and chemical miscibility on the crosslinking structure and mechanical properties of polymers cured by visible-light initiated free-radical/cationic ring-opening hybrid photopolymerization are determined. A three-component initiator system is used and the monomer system contains methacrylates and epoxides. The photopolymerization kinetics is monitored in situ by Fourier transform infrared-attenuated total reflectance. The crosslinking structure is studied by modulated differential scanning calorimetry and dynamic mechanical analysis. X-ray microcomputed tomography is used to evaluate microphase separation. The mechanical properties of polymers formed by hybrid formed by free-radical polymerization. These investigations mark the first time that the benefits of the chain transfer reaction between epoxy and hydroxyl groups of methacrylate, on the crosslinking network and microphase separation during hybrid visible-light initiated photopolymerization, have been determined.

  19. Quantitative structure-property relationship (QSPR) modeling of drug-loaded polymeric micelles via genetic function approximation.

    PubMed

    Wu, Wensheng; Zhang, Canyang; Lin, Wenjing; Chen, Quan; Guo, Xindong; Qian, Yu; Zhang, Lijuan

    2015-01-01

    Self-assembled nano-micelles of amphiphilic polymers represent a novel anticancer drug delivery system. However, their full clinical utilization remains challenging because the quantitative structure-property relationship (QSPR) between the polymer structure and the efficacy of micelles as a drug carrier is poorly understood. Here, we developed a series of QSPR models to account for the drug loading capacity of polymeric micelles using the genetic function approximation (GFA) algorithm. These models were further evaluated by internal and external validation and a Y-randomization test in terms of stability and generalization, yielding an optimization model that is applicable to an expanded materials regime. As confirmed by experimental data, the relationship between microstructure and drug loading capacity can be well-simulated, suggesting that our models are readily applicable to the quantitative evaluation of the drug-loading capacity of polymeric micelles. Our work may offer a pathway to the design of formulation experiments.

  20. Opening Furan for Tailoring Properties of Bio-based Poly(Furfuryl Alcohol) Thermoset.

    PubMed

    Falco, Guillaume; Guigo, Nathanael; Vincent, Luc; Sbirrazzuoli, Nicolas

    2018-06-11

    This work shows how furan ring-opening reactions were controlled by polymerization conditions to tune the cross-link density in bio-based poly(furfuryl alcohol) (PFA). The influence of water and isopropyl alcohol (IPA) on the polymerization of furfuryl alcohol, and particularly on furan ring-opening, was investigated by means of 13 C NMR and FT-IR spectroscopy. Results indicated that formation of open structures were favored in the presence of solvents, thus leading to modification of the thermo-mechanical properties compared to PFA cross-linked without solvent. Dynamic mechanical analyses showed that when slightly more open structures were present in PFA it resulted in an important decrease of the cross-link density. Despite lower glass-transition temperature and lower elastic modulus for PFA polymerized with solvent, the thermal stability remains very high (>350 °C) even with more open structures in PFA. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Quantitative Structure-Property Relationship (QSPR) Modeling of Drug-Loaded Polymeric Micelles via Genetic Function Approximation

    PubMed Central

    Lin, Wenjing; Chen, Quan; Guo, Xindong; Qian, Yu; Zhang, Lijuan

    2015-01-01

    Self-assembled nano-micelles of amphiphilic polymers represent a novel anticancer drug delivery system. However, their full clinical utilization remains challenging because the quantitative structure-property relationship (QSPR) between the polymer structure and the efficacy of micelles as a drug carrier is poorly understood. Here, we developed a series of QSPR models to account for the drug loading capacity of polymeric micelles using the genetic function approximation (GFA) algorithm. These models were further evaluated by internal and external validation and a Y-randomization test in terms of stability and generalization, yielding an optimization model that is applicable to an expanded materials regime. As confirmed by experimental data, the relationship between microstructure and drug loading capacity can be well-simulated, suggesting that our models are readily applicable to the quantitative evaluation of the drug-loading capacity of polymeric micelles. Our work may offer a pathway to the design of formulation experiments. PMID:25780923

  2. Polymeric dental composites based on remineralizing amorphous calcium phosphate fillers

    PubMed Central

    Skrtic, Drago; Antonucci, Joseph M.

    2017-01-01

    For over two decades we have systematically explored structure-composition-property relationships of amorphous calcium phosphate (ACP)-based polymeric dental composites. The appeal of these bioactive materials stems from their intrinsic ability to prevent demineralization and/or restore defective tooth structures via sustained release of remineralizing calcium and phosphate ions. Due to the compositional similarity of the ACP to biological tooth mineral, ACP-based composites should exhibit excellent biocompatibility. Research described in this article has already yielded remineralizing sealants and orthodontic adhesives as well as a prototype root canal sealer. Our work has also contributed to a better understanding on how polymer matrix structure and filler/matrix interactions affect the critical properties of these polymeric composites and their overall performance. The addition of antimicrobial compounds to the formulation of ACP composites could increase their medical and dental regenerative treatment applications, thereby benefiting an even greater number of patients. PMID:29599572

  3. Fibrin Clots Are Equilibrium Polymers That Can Be Remodeled Without Proteolytic Digestion

    NASA Astrophysics Data System (ADS)

    Chernysh, Irina N.; Nagaswami, Chandrasekaran; Purohit, Prashant K.; Weisel, John W.

    2012-11-01

    Fibrin polymerization is a necessary part of hemostasis but clots can obstruct blood vessels and cause heart attacks and strokes. The polymerization reactions are specific and controlled, involving strong knob-into-hole interactions to convert soluble fibrinogen into insoluble fibrin. It has long been assumed that clots and thrombi are stable structures until proteolytic digestion. On the contrary, using the technique of fluorescence recovery after photobleaching, we demonstrate here that there is turnover of fibrin in an uncrosslinked clot. A peptide representing the knobs involved in fibrin polymerization can compete for the holes and dissolve a preformed fibrin clot, or increase the fraction of soluble oligomers, with striking rearrangements in clot structure. These results imply that in vivo clots or thrombi are more dynamic structures than previously believed that may be remodeled as a result of local environmental conditions, may account for some embolization, and suggest a target for therapeutic intervention.

  4. Adjustment of automatic control systems of production facilities at coal processing plants using multivariant physico- mathematical models

    NASA Astrophysics Data System (ADS)

    Evtushenko, V. F.; Myshlyaev, L. P.; Makarov, G. V.; Ivushkin, K. A.; Burkova, E. V.

    2016-10-01

    The structure of multi-variant physical and mathematical models of control system is offered as well as its application for adjustment of automatic control system (ACS) of production facilities on the example of coal processing plant.

  5. Design, Synthesis, and Chemical Processing of Hierarchical Ceramic Structures for Aerospace Applications

    DTIC Science & Technology

    1993-03-30

    Massachusetts Institute of Technology, Cambridge, MA 02139I ABSTRACT polysilanes." Pyrolysis of these polymers usually The decomposition of polymeric SiC ...of soluble polymeric solids. Pyrolysis of these polymers in argon yielded The precursors were prepared by adding a TiC/A120 3 composite at 12501C...formation of soluble polymeric solids. Pyrolysis described an approach for synthesizing AI2O/ SiC of these polymers in argon yielded TiC/AI203

  6. Nanoscale Origin of the Dichotimous Viscosity-Pressure Behavior in Silicate Melts

    NASA Astrophysics Data System (ADS)

    Wang, Y.; Sakamaki, T.; Skiner, L.; Jing, Z.; Yu, T.; Kono, Y.; Park, C.; Shen, G.; Rivers, M. L.; Sutton, S. R.

    2013-12-01

    A defining characteristic of silicate melts is the degree of polymerization (tetrahedral connectivity), which dictates physical properties such as viscosity and density. While viscosity of depolymerized silicate melts increases with pressure consistent with free volume theory, isothermal viscosity of polymerized melts decreases with pressure up to ~3 - 5 GPa, above which it turns over to normal (positive) pressure dependence. We conducted high-pressure melt structure studies along the jadeite (Jd) - diopside (Di) join, using a Paris-Edinburgh Press at the HPCAT beamline 16-BM-B and measured Jd melt density using a DIA type apparatus based on x-ray absorption at GSECARS beamline 13-BM-D. Structures of polymerized (Jd and Jd50Di50) and depolymerized (Di) melts show distinct responses to pressure. For Jd melt, T-O, T-T bond lengths (where T denotes tetrahedrally coordinated Al and Si) and T-O-T angle all exhibit rapid, sometimes non-linear decrease with increasing pressure to ~3 GPa. For Di melt, these parameters vary linearly with pressure and change very little. Molecular dynamics calculations, constrained by the x-ray structural data, were employed to examine details of structural evolution in polymerized and depolymerized liquids. A structural model is developed to link structural evolution to changes in melt properties, such as density and viscosity, with pressure. We show that the pressure of the viscosity turnover corresponds to the tetrahedral packing limit, below which the structure is compressed through tightening of the inter-tetrahedral bond angle, resulting in continual breakup of tetrahedral connectivity and viscosity decrease. Above the turnover pressure, Si and Al coordination increases to allow further packing, with increasing viscosity. This structural response prescribes the distribution of melt viscosity and density with depth, and may be the main controlling factor for magma transport rates in terrestrial planetary interiors.

  7. Y2O3:Eu phosphor particles prepared by spray pyrolysis from a solution containing citric acid and polyethylene glycol

    NASA Astrophysics Data System (ADS)

    Roh, H. S.; Kang, Y. C.; Park, H. D.; Park, S. B.

    Y2O3:Eu phosphor particles were prepared by large-scale spray pyrolysis. The morphological control of Y2O3:Eu particles in spray pyrolysis was attempted by adding polymeric precursors to the spray solution. The effect of composition and amount of polymeric precursors on the morphology, crystallinity and photoluminescence characteristics of Y2O3:Eu particles was investigated. Particles prepared from a solution containing polyethylene glycol (PEG) with an average molecular weight of 200 had a hollow structure, while those prepared from solutions containing adequate amounts of citric acid (CA) and PEG had a spherical shape, filled morphology and clean surfaces after post-treatment at high temperature. Y2O3:Eu particles prepared from an aqueous solution with no polymeric precursors had a hollow structure and rough surfaces after post-treatment. The phosphor particles prepared from solutions with inadequate amounts of CA and/or PEG also had hollow and/or fragmented structures. The particles prepared from the solution containing 0.3 M CA and 0.3 M PEG had the highest photoluminescence emission intensity, which was 56% higher than that of the particles prepared from aqueous solution without polymeric precursors.

  8. Impregnation of β-tricalcium phosphate robocast scaffolds by in situ polymerization.

    PubMed

    Martínez-Vázquez, Francisco J; Perera, Fidel H; van der Meulen, Inge; Heise, Andreas; Pajares, Antonia; Miranda, Pedro

    2013-11-01

    Ring-opening polymerization of ε-caprolactone (ε-CL) and L-lactide (LLA) was performed to impregnate β-tricalcium phosphate (β-TCP) scaffolds fabricated by robocasting. Concentrated colloidal inks prepared from β-TCP commercial powders were used to fabricate porous structures consisting of a 3D mesh of interpenetrating rods. ε-CL and LLA were in situ polymerized within the ceramic structure by using a lipase and stannous octanoate, respectively, as catalysts. The results show that both the macropores inside the ceramic mesh and the micropores within the ceramic rods are full of polymer in either case. The mechanical properties of scaffolds impregnated by in situ polymerization (ISP) are significantly increased over those of the bare structures, exhibiting similar values than those obtained by other, more aggressive, impregnation methods such as melt-immersion (MI). ISP using enzymatic catalysts requires a reduced processing temperature which could facilitate the incorporation of growth factors and other drugs into the polymer composition, thus enhancing the bioactivity of the composite scaffold. The implications of these results for the optimization of the mechanical and biological performance of scaffolds for bone tissue engineering applications are discussed. Copyright © 2013 Wiley Periodicals, Inc.

  9. Well-Defined Macromolecules Using Horseradish Peroxidase as a RAFT Initiase.

    PubMed

    Danielson, Alex P; Bailey-Van Kuren, Dylan; Lucius, Melissa E; Makaroff, Katherine; Williams, Cameron; Page, Richard C; Berberich, Jason A; Konkolewicz, Dominik

    2016-02-01

    Enzymatic catalysis and control over macromolecular architectures from reversible addition-fragmentation chain transfer polymerization (RAFT) are combined to give a new method of making polymers. Horseradish peroxidase (HRP) is used to catalytically generate radicals using hydrogen peroxide and acetylacetone as a mediator. RAFT is used to control the polymer structure. HRP catalyzed RAFT polymerization gives acrylate and acrylamide polymers with relatively narrow molecular weight distributions. The polymerization is rapid, typically exceeding 90% monomer conversion in 30 min. Complex macromolecular architectures including a block copolymer and a protein-polymer conjugate are synthesized using HRP to catalytically initiate RAFT polymerization. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Silicoaluminates as “Support Activator” Systems in Olefin Polymerization Processes

    PubMed Central

    Tabernero, Vanessa; Camejo, Claudimar; Terreros, Pilar; Alba, María Dolores; Cuenca, Tomás

    2010-01-01

    In this work we report the polymerization behaviour of natural clays (montmorillonites, MMT) as activating supports. These materials have been modified by treatment with different aluminium compounds in order to obtain enriched aluminium clays and to modify the global Brönsted/Lewis acidity. As a consequence, the intrinsic structural properties of the starting materials have been changed. These changes were studied and these new materials used for ethylene polymerization using a zirconocene complex as catalyst. All the systems were shown to be active in ethylene polymerization. The catalyst activity and the dependence on acid strength and textural properties have been also studied. The behaviour of an artificial silica (SBA 15) modified with an aluminium compound to obtain a silicoaluminate has been studied, but no ethylene polymerization activity has been found yet.

  11. Symposium on Explosives and Pyrotechnics, 13th, Hilton Head Island, SC, Dec. 2-4, 1986, Proceedings

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1987-01-01

    The present conference on explosive and pyrotechnic technologies discusses the shock-sensitivity of RDX, the thermodynamic properties of RDX, TNT, nitroglycerine, and HMX energetic molecules, the dynamic resistivity of exploding conductors, the decomposition of azides, the critical shock-initiation energy of emulsion explosives, actuator valve optimization, pyrotechnic aerosolization from novel imbibed liquid matrices, tetrazole initiators, and polymeric binders for red phosphorus pellets. Also discussed are channel-effect studies, the dynamic desensitization of coal mine explosives, the electromagnetic and electrostatic protection of explosives, the reliability of fuze explosive trains, the hazardous properties of explosive chemicals, the emulsification of an explosive with a chemical foamingmore » agent, and low energy ignition of HMX using a foil bridge.« less

  12. Mode of occurrence of chromium in four US coals

    USGS Publications Warehouse

    Huggins, Frank E.; Shah, N.; Huffman, G.P.; Kolker, A.; Crowley, S.; Palmer, C.A.; Finkelman, R.B.

    2000-01-01

    The mode of occurrence of chromium in three US bituminous coals and one US subbituminous has been examined using both X-ray absorption fine structure (XAFS) spectroscopy and a selective leaching protocol supplemented by scanning electron microscopy (SEM) and electron microprobe measurements. A synthesis of results from both methods indicates that chromium occurs principally in two forms in the bituminous coals: the major occurrence of chromium is associated with the macerals and is not readily leached by any reagent, whereas a second, lesser occurrence, which is leachable in hydrofluoric acid (HF), is associated with the clay mineral, illite. The former occurrence is believed to be a small particle oxyhydroxide phase (CrO(OH)). One coal also contained a small fraction (<5%) of the chromium in the form of a chromian magnetite, and the leaching protocol indicated the possibility of a similar small fraction of chromium in sulfide form in all three coals. There was little agreement between the two techniques on the mode of occurrence of chromium in the subbituminous coal; however, only a limited number of subbituminous coals have been analyzed by either technique. The chromium in all four coals was trivalent as no evidence was found for the Cr6+ oxidation state in any coal.

  13. CO2 sequestration potential of Charqueadas coal field in Brazil

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Romanov, V; Santarosa, C; Crandall, D

    2013-02-01

    Although coal is not the primary source of energy in Brazil there is growing interest to evaluate the potential of coal from the south of the country for various activities. The I2B coal seamin the Charqueadas coal field has been considered a target for enhanced coal bed methane production and CO2 sequestration. A detailed experimental study of the samples from this seam was conducted at the NETL with assistance from the Pontif?cia Universidade Cat?lica Do Rio Grande Do Sul. Such properties as sorption capacity, internal structure of the samples, porosity and permeability were of primary interest in this characterization study.more » The samples used were low rank coals (high volatile bituminous and sub-bituminous) obtained from the I2B seam. It was observed that the temperature effect on adsorption capacity correlates negatively with as-received water and mineral content. Langmuir CO2 adsorption capacity of the coal samples ranged 0.61?2.09 mmol/g. The upper I2B seam appears to be overall more heterogeneous and less permeable than the lower I2B seam. The lower seam coal appears to have a large amount of micro-fractures that do not close even at 11 MPa of confining pressure.« less

  14. Acoustic emission and sorptive deformation induced in coals of various rank by the sorption-desorption of gas

    NASA Astrophysics Data System (ADS)

    Majewska, Zofia; Ziętek, Jerzy

    2007-09-01

    Simultaneous measurements of acoustic emission (AE) and expansion/contraction of coal samples subjected to gas sorption-desorption processes were conducted on high-and medium-rank coal. The aim of this study was to examine the influence of the coal rank and type of sorbate on measured AE and strain characteristics. The experimental equipment employed in this study consisted of a pressure vessel and associated pressurisation and monitoring units. The arrangement of pressure-vacuum valves permitted the coal sample to be pressurised and depressurised. Carbon-dioxide and methane were used as sorbats. Acoustic emission and strains were recorded continuously for a period of 50 hours during sorption and for at least 12 hours during the desorption process. Tests were conducted on cylindrical coal samples at 298 K. The experimental data were presented as plots of AE basic parameters versus time and in strain diagrams. These studies lead to the following conclusions: 1. There are significant differences in AE and strain characteristics for the two systems (coal-CO2 and coal-CH4); 2. There is a direct influence of rank and type of coal on its behaviour during the sorption-desorption of gas. An attempt has been made to interpret the results obtained on the grounds of the copolymer model of coal structure. More research is needed into this topic in order to get a quantitative description of the observed facts.

  15. Structural Basis of Actin Filament Nucleation by Tandem W Domains

    PubMed Central

    Chen, Xiaorui; Ni, Fengyun; Tian, Xia; Kondrashkina, Elena; Wang, Qinghua; Ma, Jianpeng

    2013-01-01

    SUMMARY Spontaneous nucleation of actin is very inefficient in cells. To overcome this barrier, cells have evolved a set of actin filament nucleators to promote rapid nucleation and polymerization in response to specific stimuli. However, the molecular mechanism of actin nucleation remains poorly understood. This is hindered largely by the fact that actin nucleus, once formed, rapidly polymerizes into filament, thus making it impossible to capture stable multisubunit actin nucleus. Here, we report an effective double-mutant strategy to stabilize actin nucleus by preventing further polymerization. Employing this strategy, we solved the crystal structure of AMPPNP-actin in complex with the first two tandem W domains of Cordon-bleu (Cobl), a potent actin filament nucleator. Further sequence comparison and functional studies suggest that the nucleation mechanism of Cobl is probably shared by the p53 cofactor JMY, but not Spire. Moreover, the double-mutant strategy opens the way for atomic mechanistic study of actin nucleation and polymerization. PMID:23727244

  16. Preparation and Structural Studies on Hybrid Core-Shell Nanoparticles Consisting of Silica Core and Conjugated Block Copolymer Shell Prepared by Surface-Initiated Polymerization

    NASA Astrophysics Data System (ADS)

    Chatterjee, Sourav; Karam, Tony; Rosu, Cornelia; Li, Xin; Do, Changwoo; Youm, Sang Gil; Haber, Louis; Russo, Paul; Nesterov, Evgueni

    Controlled Kumada catalyst-transfer polymerization occurring by chain-growth mechanism was developed for the synthesis of conjugated polymers and block copolymers from the surface of inorganic substrates such as silica nanoparticles. Although synthesis of conjugated polymers via Kumada polymerization became an established method for solution polymerization, carrying out the same reaction in heterogeneous conditions to form monodisperse polymer chains still remains a challenge. We developed and described a simple and efficient approach to the preparation of surface-immobilized layer of catalytic Ni(II) initiator, and demonstrated using it to prepare polymers and block copolymers on silica nanoparticle. The structure of the resulting hybrid nanostructures was thoroughly studied using small-angle neutron and X-ray scattering, thermal analysis, and optical spectroscopy. The photoexcitation energy transfer processes in the conjugated polymer shell were studied via steady-state and time resolved transient absorption spectroscopy. This study uncovered important details of the energy transfer, which will be discussed in this presentation.

  17. Cluster-mediated assembly enables step-growth copolymerization from binary nanoparticle mixtures with rationally designed architectures† †Electronic supplementary information (ESI) available. See DOI: 10.1039/c8sc00220g

    PubMed Central

    Zhang, Xianfeng; Lv, Longfei; Wu, Guanhong; Yang, Dong

    2018-01-01

    Directed co-assembly of binary nanoparticles (NPs) into one-dimensional copolymer-like chains is fascinating but challenging in the realm of material science. While many strategies have been developed to induce the polymerization of NPs, it remains a grand challenge to produce colloidal copolymers with widely tailored compositions and precisely controlled architectures. Herein we report a robust colloidal polymerization strategy, which enables the growth of sophisticated NP chains with elaborately designed structures. By quantifying NP assembly statistics and kinetics, we establish that the linear assembly of colloidal NPs, with the assistance of PbSO4 clusters, follows a step-growth polymerization mechanism, and on the basis of this, we design and fabricate NP chains structurally analogous to random, block, and alternating copolymers, respectively. Our studies offer mechanistic insights into cluster-mediated colloidal polymerization, paving the way toward the rational synthesis of colloidal copolymers with quantitatively predicted architectures and functionalities. PMID:29862003

  18. Investigation on the activation of coal gangue by a new compound method.

    PubMed

    Li, Chao; Wan, Jianhua; Sun, Henghu; Li, Longtu

    2010-07-15

    In order to comprehensively utilize coal gangue as the main raw material in cementitious materials, improving its cementitious activity is a question of fundamental importance. In this paper, we present a new compound mechanical-hydro-thermal activation (CMHTA) technology to investigate the activation effect of coal gangue, and the traditional mechanical-thermal activation (TMTA) technology was used as reference. The purpose of this study is to give a detailed comparison between these two methods with regard to the mineral composition, crystal structure and microstructure, by XRD, IR, MAS NMR, XPS and mechanical property analysis. The prepared coal gangue based blended cement, containing 52% of activated coal gangue C (by CMHTA technology), has a better mechanical property than activated coal gangue T (by TMTA technology) and raw coal gangue. The results show that both of the TMTA and CMHTA technologies can improve the cementitious activity of raw gangue greatly. Moreover, compared with TMTA, the mineral phases such as feldspar and muscovite in raw coal gangue were partially decomposed, and the crystallinity of quartz decreased, due to the effect of adding CaO and hydro-thermal process of CMHTA technology. 2010 Elsevier B.V. All rights reserved.

  19. Adsorption isotherms and kinetics of activated carbons produced from coals of different ranks.

    PubMed

    Purevsuren, B; Lin, Chin-Jung; Davaajav, Y; Ariunaa, A; Batbileg, S; Avid, B; Jargalmaa, S; Huang, Yu; Liou, Sofia Ya-Hsuan

    2015-01-01

    Activated carbons (ACs) from six coals, ranging from low-rank lignite brown coal to high-rank stone coal, were utilized as adsorbents to remove basic methylene blue (MB) from an aqueous solution. The surface properties of the obtained ACs were characterized via thermal analysis, N2 isothermal sorption, scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy and Boehm titration. As coal rank decreased, an increase in the heterogeneity of the pore structures and abundance of oxygen-containing functional groups increased MB coverage on its surface. The equilibrium data fitted well with the Langmuir model, and adsorption capacity of MB ranged from 51.8 to 344.8 mg g⁻¹. Good correlation coefficients were obtained using the intra-particle diffusion model, indicating that the adsorption of MB onto ACs is diffusion controlled. The values of the effective diffusion coefficient ranged from 0.61 × 10⁻¹⁰ to 7.1 × 10⁻¹⁰ m² s⁻¹, indicating that ACs from lower-rank coals have higher effective diffusivities. Among all the ACs obtained from selected coals, the AC from low-rank lignite brown coal was the most effective in removing MB from an aqueous solution.

  20. Competitiveness and potentials of UCG-CCS on the European energy market

    NASA Astrophysics Data System (ADS)

    Kempka, T.; Nakaten, N.; Schlüter, R.; Fernandez-Steeger, T.; Azzam, R.

    2009-04-01

    The world-wide coal reserves can satisfy the world's primary energy demand for several hundred years. However, deep coal deposits with seams of low thickness and structural complexity do currently not allow an economic exploitation of many deposits. Here, underground coal gasification (UCG) can offer an economical approach for coal extraction. The intended overall process relies on coal deposit exploitation using directed drillings located at the coal seam base and the subsequent in situ coal conversion into a synthesis gas. The resulting synthesis gas is used for electricity generation in a combined cycle plant at the surface. A reduction of the CO2 emissions resulting from the combined process is realized by subsequent CO2 capture and its injection into the previously gasified coal seams. The scope of the present study was the investigation of UCG-CCS competitiveness on the European energy market and the determination of the impacting factors. For that purpose, a modular model for calculation of UCG-CCS electricity generation costs was implemented and adapted to the most relevant process parameters. Furthermore, the range of energy supply coverage was estimated based on different German energy generation scenarios.

  1. Use of molecular modeling to determine the interaction and competition of gases within coal for carbon dioxide sequestration

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jeffrey D. Evanseck; Jeffry D. Madura; Jonathan P. Mathews

    2006-04-21

    Molecular modeling was employed to both visualize and probe our understanding of carbon dioxide sequestration within a bituminous coal. A large-scale (>20,000 atoms) 3D molecular representation of Pocahontas No. 3 coal was generated. This model was constructed based on a the review data of Stock and Muntean, oxidation and decarboxylation data for aromatic clustersize frequency of Stock and Obeng, and the combination of Laser Desorption Mass Spectrometry data with HRTEM, enabled the inclusion of a molecular weight distribution. The model contains 21,931 atoms, with a molecular mass of 174,873 amu, and an average molecular weight of 714 amu, with 201more » structural components. The structure was evaluated based on several characteristics to ensure a reasonable constitution (chemical and physical representation). The helium density of Pocahontas No. 3 coal is 1.34 g/cm{sup 3} (dmmf) and the model was 1.27 g/cm{sup 3}. The structure is microporous, with a pore volume comprising 34% of the volume as expected for a coal of this rank. The representation was used to visualize CO{sub 2}, and CH{sub 4} capacity, and the role of moisture in swelling and CO{sub 2}, and CH{sub 4} capacity reduction. Inclusion of 0.68% moisture by mass (ash-free) enabled the model to swell by 1.2% (volume). Inclusion of CO{sub 2} enabled volumetric swelling of 4%.« less

  2. Synthesis and structural studies of heterobimetallic alkoxide complexes supported by bis(phenolate) ligands: efficient catalysts for ring-opening polymerization of L-lactide.

    PubMed

    Chen, Hsuan-Ying; Liu, Mei-Yu; Sutar, Alekha Kumar; Lin, Chu-Chieh

    2010-01-18

    A series of heterobimetallic titanium(IV) complexes [LTi(O(i)Pr)(mu-O(i)Pr)(2)Li(THF)(2)], [LTi(O(i)Pr)(mu-O(i)Pr)(2)Na(THF)(2)], [LTi(mu-O(i)Pr)(2)Zn(O(i)Pr)(2)], and [LTi(mu-O(i)Pr)(2)Mg(O(i)Pr)(2)] (where L = bidentate bisphenol ligands) have been synthesized and characterized including a structural determination of [L(1)Ti(mu(2)-O(i)Pr)(2)(O(i)Pr)Li(THF)(2)] (1a). These complexes were investigated for their utility in the ring-opening polymerization (ROP) of l-lactide (LA). Polymerization activities have been shown to correlate with the electronic properties of the substituent within the bisphenol ligand. In contrast to monometallic titanium initiator 1e, all the heterobimetallic titanium initiators (Ti-Li, Ti-Na, Ti-Zn, and Ti-Mg) show enhanced catalytic activity toward ring-opening polymerization (ROP) of l-LA. In addition, the use of electron-donating methoxy or methylphenylsulfonyl functional ligands reveals the highest activity. The bisphenol bimetallic complexes give rise to controlled ring-opening polymerization, as shown by the linear relationship between the percentage conversion and the number-average molecular weight. The polymerization kinetics using 2c as an initiator were also studied, and the experimental results indicate that the reaction rate is first-order with respect to both monomer and catalyst concentration with a polymerization rate constant, k = 81.64 M(-1) min(-1).

  3. Fibronectin Deposition Participates in Extracellular Matrix Assembly and Vascular Morphogenesis

    PubMed Central

    Hielscher, Abigail; Ellis, Kim; Qiu, Connie; Porterfield, Josh; Gerecht, Sharon

    2016-01-01

    The extracellular matrix (ECM) has been demonstrated to facilitate angiogenesis. In particular, fibronectin has been documented to activate endothelial cells, resulting in their transition from a quiescent state to an active state in which the cells exhibit enhanced migration and proliferation. The goal of this study is to examine the role of polymerized fibronectin during vascular tubulogenesis using a 3 dimensional (3D) cell-derived de-cellularized matrix. A fibronectin-rich 3D de-cellularized ECM was used as a scaffold to study vascular morphogenesis of endothelial cells (ECs). Confocal analyses of several matrix proteins reveal high intra- and extra-cellular deposition of fibronectin in formed vascular structures. Using a small peptide inhibitor of fibronectin polymerization, we demonstrate that inhibition of fibronectin fibrillogenesis in ECs cultured atop de-cellularized ECM resulted in decreased vascular morphogenesis. Further, immunofluorescence and ultrastructural analyses reveal decreased expression of stromal matrix proteins in the absence of polymerized fibronectin with high co-localization of matrix proteins found in association with polymerized fibronectin. Evaluating vascular kinetics, live cell imaging showed that migration, migration velocity, and mean square displacement, are disrupted in structures grown in the absence of polymerized fibronectin. Additionally, vascular organization failed to occur in the absence of a polymerized fibronectin matrix. Consistent with these observations, we tested vascular morphogenesis following the disruption of EC adhesion to polymerized fibronectin, demonstrating that block of integrins α5β1 and αvβ3, abrogated vascular morphogenesis. Overall, fibronectin deposition in a 3D cell-derived de-cellularized ECM appears to be imperative for matrix assembly and vascular morphogenesis. PMID:26811931

  4. Similar simulation study on the characteristics of the electric potential response to coal mining

    NASA Astrophysics Data System (ADS)

    Niu, Yue; Li, Zhonghui; Kong, Biao; Wang, Enyuan; Lou, Quan; Qiu, Liming; Kong, Xiangguo; Wang, Jiali; Dong, Mingfu; Li, Baolin

    2018-02-01

    An electric potential (EP) can be generated during the failure process of coal and rock. In this article, a similar physical model of coal rock was built and the characteristics of the EP responding to the process of coal mining were studied. The results showed that, at the early mining stage, the structure of coal rock strata were stable in the simulation model, the support stress of overlying coal rock strata was low and the maximum subsidence was little, while the EP change was less. With the advancement of the working face, the support stress of the overlying coal rock strata in the mined-out area changed dramatically, the maximum subsidence increased constantly, the deformation and destruction were aggravated, and cracks expanded continuously. Meanwhile, the EP response was significant with fluctuation. When significant macro damage appeared in coal rock strata, the EP signal fluctuation was violent. The overlying coal rock strata were influenced by gravity and mining activity. During the mining process, the crack growth and the friction, together with slip between coal and rock particles, resulted in the response of EP. The change in EP was closely related to the damage state and stress distribution of the coal rock strata. EP monitoring has the advantages of accurate reflection and strong anti-interference in the field. Therefore, with further study, an EP monitoring method could be applied for monitoring and early warning of coal and rock dynamic disaster, and risk evaluation in the future. The strength of the EP and its fluctuation degree could serve as the key discrimination indexes.

  5. Structural Impairments of Hippocampus in Coal Mine Gas Explosion-Related Posttraumatic Stress Disorder

    PubMed Central

    Lang, Xu; Li, Huabing; Qin, Wen; Yu, Chunshui

    2014-01-01

    Investigations on hippocampal and amygdalar volume have revealed inconsistent results in patients with posttraumatic stress disorder (PTSD). Little is known about the structural covariance alterations between the hippocampus and amygdala in PTSD. In this study, we evaluated the alteration in the hippocampal and amygdalar volume and their structural covariance in the coal mine gas explosion related PTSD. High resolution T1-weighted magnetic resonance imaging (MRI) was performed on coal mine gas explosion related PTSD male patients (n = 14) and non-traumatized coalminers without PTSD (n = 25). The voxel-based morphometry (VBM) method was used to test the inter-group differences in hippocampal and amygdalar volume as well as the inter-group differences in structural covariance between the ipsilateral hippocampus and amygdala. PTSD patients exhibited decreased gray matter volume (GMV) in the bilateral hippocampi compared to controls (p<0.05, FDR corrected). GMV covariances between the ipsilateral hippocampus and amygdala were significantly reduced in PTSD patients compared with controls (p<0.05, FDR corrected). The coalminers with gas explosion related PTSD had decreased hippocampal volume and structural covariance with the ipsilateral amygdala, suggesting that the structural impairment of the hippocampus may implicate in the pathophysiology of PTSD. PMID:25000505

  6. Geoenvironmental impacts of using high carbon fly ash in structural fill applications : [research summary].

    DOT National Transportation Integrated Search

    2013-03-01

    Coal power plants generate approximately 50% of the electricity in the : United States. As a result, large amounts of coal combustion byproducts, : especially fly ash, are produced annually. Only 40% of the fly ash : (mainly C and F-type classificati...

  7. 30 CFR 75.1434 - Retirement criteria.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Hoisting and Mantrips Wire Ropes § 75.1434 Retirement... structure; (f) Heat damage from any source; (g) Diameter reduction due to wear that exceeds six percent of...

  8. 30 CFR 77.1100 - Fire protection; training and organization.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ....1100 Section 77.1100 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS, SURFACE COAL MINES AND SURFACE WORK AREAS OF... facilities and equipment shall be provided commensurate with the potential fire hazards at each structure...

  9. Organic geochemical studies of the transformation of gymnospermous xylem during peatification and coalification to subbituminous coal

    USGS Publications Warehouse

    Hatcher, P.G.; Lerch, H. E.; Verheyen, T.V.

    1990-01-01

    It is generally recognized that xylem from trees that are buried in peat swamps is transformed first to huminite macerals in brown coal and then to vitrinite macerals in bituminous coal by processes collectively known as coalification. In order to understand the chemical nature of coalification of xylem and the chemical structures that eventually evolve in coal, we examined a series of gymnospermous xylem samples coalified to varying degrees. The samples included modern fresh xylem, modern degraded xylem in peat, and xylem coalified to ranks of brown coal (lignite B), lignite A, and subbituminous coal. The organic geochemical methods used in this study included solid-state 13C nuclear magnetic resonance (NMR) and pyrolysis/gas chromatography/mass spectrometry. The NMR method provided average compositional information, and the pyrolysis provided detailed molecular information. Although the samples examined include different plants of different geologic ages, they all share a common feature in that they are gymnospermous and presumably have or had a similar kind of lignin. The data obtained in this study provide enough details to allow delineation of specific coalification pathway for the xylem is microbial degradation in peat (peatification), leading to selective removal of cellulosic components. These components constitute a large fraction of the total mass of xylem, usually greater than 50%. Although cellulosic components can survive degradation under certain conditions, their loss during microbial degradation is the rule rather than exception during peatification. As these components of xylem are degraded and lost, lignin, another major component of xylem, is selectively enriched because it is more resistant to microbial degradation than the cellulosic components. Thus, lignin survives peatification in a practically unaltered state and becomes the major precursor of coalified xylem. During its transformation to brown coal and lignite A, lignin in xylem is altered by two important processes. The first involves loss of methoxyl groups, primarily by demethylation (Fig. 1A). The end products of demethylation are catechol-like structures as shown below in Figure 1B. The second transformation process involves increased cross-linking of the aromatic rings. This cross-linking induces increased carbon substitution of the aromatic rings such that the lignin-derived structures become more highly condensed. During its conversion to coalified xylem in subbituminous coal, lignitic xylem, composed primarily of condensed catechol-like structures, is transformed to a macromolecular material primarily composed of phenol-like structures. The catechol-like structures of lignitic xylem loose a hydroxyl group, which is replaced by a hydrogen to form the phenol-like structure as shown in the example in Figure 1B. The pyrolysis data provided only a few clues as to the fate of the C3-side chain of lignin during coalification. However, the NMR data suggest that this side chain is altered, probably by loss of the hydroxyl groups that are attached in modern lignin. Interference in the NMR analysis by aliphatic components of wood, such as resins, precludes definitive determinations of the fate of the C3-side chain during coalification. ?? 1990.

  10. Superacid Catalyzed Coal Conversion Chemistry. Final Technical Report, September 1, 1983-September 1, 1986

    DOE R&D Accomplishments Database

    Olah, G. A.

    1986-01-01

    This research project involved the study of a raw comparatively mild coal conversion process. The goal of the project was to study model systems to understand the basic chemistry involved and to provide a possible effective pretreatment of coal which significantly improves liquefaction-depolymerization under mild conditions. The conversion process operates at relatively low temperatures (170 degrees C) and pressures and uses an easily recyclable, stable superacid catalysts (HF-BF{sub 3}). It consequently offers an attractive alternative to currently available processes. From the present studies it appears that the modification of coal structure by electrophilic alkylation and subsequent reaction of alkylated coal with HF-BF{sub 3}-H{sub 2} system under mild conditions considerably improves the extractability of coal in pyridine and cyclohexane. On the other hand, nitration of coal and its subsequent reaction with HF-BF{sub 3}H{sub 2} decreases the pyridine and cyclohexane extractability. Study of model compounds under conditions identical with the superacidic HF/BF{sub 3}/H{sub 2} system provided significant information about the basic chemistry of the involved cleavage-hydrogenation reactions.

  11. Ullmann-type coupling of brominated tetrathienoanthracene on copper and silver

    NASA Astrophysics Data System (ADS)

    Gutzler, Rico; Cardenas, Luis; Lipton-Duffin, Josh; El Garah, Mohamed; Dinca, Laurentiu E.; Szakacs, Csaba E.; Fu, Chaoying; Gallagher, Mark; Vondráček, Martin; Rybachuk, Maksym; Perepichka, Dmitrii F.; Rosei, Federico

    2014-02-01

    We report the synthesis of extended two-dimensional organic networks on Cu(111), Ag(111), Cu(110), and Ag(110) from thiophene-based molecules. A combination of scanning tunnelling microscopy and X-ray photoemission spectroscopy yields insight into the reaction pathways from single molecules towards the formation of two-dimensional organometallic and polymeric structures via Ullmann reaction dehalogenation and C-C coupling. The thermal stability of the molecular networks is probed by annealing at elevated temperatures of up to 500 °C. On Cu(111) only organometallic structures are formed, while on Ag(111) both organometallic and covalent polymeric networks were found to coexist. The ratio between organometallic and covalent bonds could be controlled by means of the annealing temperature. The thiophene moieties start degrading at 200 °C on the copper surface, whereas on silver the degradation process becomes significant only at 400 °C. Our work reveals how the interplay of a specific surface type and temperature steers the formation of organometallic and polymeric networks and describes how these factors influence the structural integrity of two-dimensional organic networks.We report the synthesis of extended two-dimensional organic networks on Cu(111), Ag(111), Cu(110), and Ag(110) from thiophene-based molecules. A combination of scanning tunnelling microscopy and X-ray photoemission spectroscopy yields insight into the reaction pathways from single molecules towards the formation of two-dimensional organometallic and polymeric structures via Ullmann reaction dehalogenation and C-C coupling. The thermal stability of the molecular networks is probed by annealing at elevated temperatures of up to 500 °C. On Cu(111) only organometallic structures are formed, while on Ag(111) both organometallic and covalent polymeric networks were found to coexist. The ratio between organometallic and covalent bonds could be controlled by means of the annealing temperature. The thiophene moieties start degrading at 200 °C on the copper surface, whereas on silver the degradation process becomes significant only at 400 °C. Our work reveals how the interplay of a specific surface type and temperature steers the formation of organometallic and polymeric networks and describes how these factors influence the structural integrity of two-dimensional organic networks. Electronic supplementary information (ESI) available: Additional STM data and DFT results. See DOI: 10.1039/c3nr05710k

  12. Impact of low-pressure glow-discharge-pulsed plasma polymerization on properties of polyaniline thin films

    NASA Astrophysics Data System (ADS)

    Jatratkar, Aviraj A.; Yadav, Jyotiprakash B.; Deshmukh, R. R.; Barshilia, Harish C.; Puri, Vijaya; Puri, R. K.

    2016-12-01

    This study reports on polyaniline thin films deposited on a glass substrate using a low-pressure glow-discharge-pulsed plasma polymerization method. The polyaniline thin film obtained by pulsed plasma polymerization has been successfully demonstrated as an optical waveguide with a transmission loss of 3.93 dB cm-1, and has the potential to be employed in integrated optics. An attempt has been made to investigate the effect of plasma OFF-time on the structural, optical as well as surface properties of polyaniline thin film. The plasma ON-time has been kept constant and the plasma OFF-time has been varied throughout the work. The plasma OFF-time strongly influenced the properties of the polyaniline thin film, and a nanostructured and compact surface was revealed in the morphological studies. The plasma OFF-time was found to enhance film thickness, roughness, refractive index and optical transmission loss, whereas it reduced the optical band gap of the polyaniline thin films. Retention in the aromatic structure was confirmed by FTIR results. Optical studies revealed a π-π* electronic transition at about 317 nm as well as the formation of a branched structure. As compared with continuous wave plasma, pulsed plasma polymerization shows better properties. Pulsed plasma polymerization reduced the roughness of the film from 1.2 nm to 0.42 nm and the optical transmission loss from 6.56 dB cm-1 to 3.39 dB cm-1.

  13. Fabricating small-scale, curved, polymeric structures with convex and concave menisci through interfacial free energy equilibrium.

    PubMed

    Cheng, Chao-Min; Matsuura, Koji; Wang, I-Jan; Kuroda, Yuka; LeDuc, Philip R; Naruse, Keiji

    2009-11-21

    Polymeric curved structures are widely used in imaging systems including optical fibers and microfluidic channels. Here, we demonstrate that small-scale, poly(dimethylsiloxane) (PDMS)-based, curved structures can be fabricated through controlling interfacial free energy equilibrium. Resultant structures have a smooth, symmetric, curved surface, and may be convex or concave in form based on surface tension balance. Their curvatures are controlled by surface characteristics (i.e., hydrophobicity and hydrophilicity) of the molds and semi-liquid PDMS. In addition, these structures are shown to be biocompatible for cell culture. Our system provides a simple, efficient and economical method for generating integrateable optical components without costly fabrication facilities.

  14. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gaczynska, Maria; Karpowicz, Przemyslaw; Stuart, Christine E.

    α 1-Proteinase inhibitor (antitrypsin) is a canonical example of the serpin family member that binds and inhibits serine proteases. The natural metastability of serpins is crucial to carry out structural rearrangements necessary for biological activity. However, the enhanced metastability of the mutant Z variant of antitrypsin, in addition to folding defect, may substantially contribute to its polymerization, a process leading to incurable serpinopathy. The metastability also impedes structural studies on the polymers. There are no crystal structures of Z monomer or any kind of polymers larger than engineered wild type (WT) trimer. Our understanding of polymerization mechanisms is based onmore » biochemical data using in vitro generated WT oligomers and molecular simulations. Here we applied atomic force microscopy (AFM) to compare topography of monomers, in vitro formed WT oligomers, and Z type polymers isolated from transgenic mouse liver. We found the AFM images of monomers closely resembled an antitrypsin outer shell modeled after the crystal structure. We confirmed that the Z variant demonstrated higher spontaneous propensity to dimerize than WT monomers. We also detected an unexpectedly broad range of different types of polymers with periodicity and topography depending on the applied method of polymerization. Short linear oligomers of unit arrangement similar to the Z polymers were especially abundant in heat-treated WT preparations. Long linear polymers were a prominent and unique component of liver extracts. However, the liver preparations contained also multiple types of oligomers of topographies undistinguishable from those found inWT samples polymerized with heat, low pH or guanidine hydrochloride treatments. In conclusion, we established that AFM is an excellent technique to assess morphological diversity of antitrypsin polymers, which is important for etiology of serpinopathies. These data also support previous, but controversial models of in vivo polymerization showing a surprising diversity of polymer topography. PLOS« less

  15. Antimicrobial Polymeric Materials with Quaternary Ammonium and Phosphonium Salts

    PubMed Central

    Xue, Yan; Xiao, Huining; Zhang, Yi

    2015-01-01

    Polymeric materials containing quaternary ammonium and/or phosphonium salts have been extensively studied and applied to a variety of antimicrobial-relevant areas. With various architectures, polymeric quaternary ammonium/phosphonium salts were prepared using different approaches, exhibiting different antimicrobial activities and potential applications. This review focuses on the state of the art of antimicrobial polymers with quaternary ammonium/phosphonium salts. In particular, it discusses the structure and synthesis method, mechanisms of antimicrobial action, and the comparison of antimicrobial performance between these two kinds of polymers. PMID:25667977

  16. Pervaporation separation of ethanol-water mixtures using polyethylenimine composite membranes

    DOEpatents

    Neidlinger, H.H.; Schissel, P.O.; Orth, R.A.

    1987-04-21

    Synthetic, organic, polymeric membranes were prepared from polyethylenimine for use with pervaporation apparatus in the separation of ethanol-water mixtures. The polymeric material was prepared in dilute aqueous solution and coated onto a polysulfone support film, from which excess polymeric material was subsequently removed. Cross-links were then generated by limited exposure to toluene-2,4-diisocyanate solution, after which the prepared membrane was heat-cured. The resulting membrane structures showed high selectivity in permeating ethanol or water over a wide range of feed concentrations.

  17. Pervaporation separation of ethanol-water mixtures using polyethylenimine composite membranes

    DOEpatents

    Neidlinger, Hermann H.; Schissel, Paul O.; Orth, Richard A.

    1987-01-01

    Synthetic, organic, polymeric membranes were prepared from polyethylenimine for use with pervaporation apparatus in the separation of ethanol-water mixtures. The polymeric material was prepared in dilute aqueous solution and coated onto a polysulfone support film, from which excess polymeric material was subsequently removed. Cross-links were then generated by limited exposure to toluene-2,4-diisocyanate solution, after which the prepared membrane was heat-cured. The resulting membrane structures showed high selectivity in permeating ethanol or water over a wide range of feed concentrations.

  18. Recent progress of atomic layer deposition on polymeric materials.

    PubMed

    Guo, Hong Chen; Ye, Enyi; Li, Zibiao; Han, Ming-Yong; Loh, Xian Jun

    2017-01-01

    As a very promising surface coating technology, atomic layer deposition (ALD) can be used to modify the surfaces of polymeric materials for improving their functions and expanding their application areas. Polymeric materials vary in surface functional groups (number and type), surface morphology and internal structure, and thus ALD deposition conditions that typically work on a normal solid surface, usually do not work on a polymeric material surface. To date, a large variety of research has been carried out to investigate ALD deposition on various polymeric materials. This paper aims to provide an in-depth review of ALD deposition on polymeric materials and its applications. Through this review, we will provide a better understanding of surface chemistry and reaction mechanism for controlled surface modification of polymeric materials by ALD. The integrated knowledge can aid in devising an improved way in the reaction between reactant precursors and polymer functional groups/polymer backbones, which will in turn open new opportunities in processing ALD materials for better inorganic/organic film integration and potential applications. Copyright © 2016 Elsevier B.V. All rights reserved.

  19. [Preparation and structural analysis of diatomite-supported SPFS flocculant].

    PubMed

    Zheng, Huai-li; Fang, Hui-li; Jiang, Shao-jie; Yang, Chun; Ma, Jiang-ya; Zhang, Zhao-qing

    2011-07-01

    In the presetn study, polymerized ferric sulphate (PFS) flocculant was prepared and tested. In the preparation of PFS flocculant, industrial by-product ferrous sulfate heptahydrate (FeSO4.7H2O) was reused as the main material. By composition with diatomite and drying up at certain temperature in vacuum drying oven, solid PFS flocculant was produced. Structural characteristics of the new flocculant product were examined through infrared spectroscopy and scanning electron microscopy (SEM), which showed that by compositing with diatomite, new group bridging emerged in the structure of PFS, which made the bond of groups stronger. In addition, part of the metalic contents in diatomite was polymerized with PFS, the product of which was polymerized ferric complex. Furthermore, the absorbing and agglomerating capacity of the diatomite carrier was significant. Considering the factors listed above, the new solid polymerized ferric sulphate (SPFS) flocculant was characterized with a larger molecule structure and enhanced absorbing, bridging and rolling sweep capacities. Through orthogonal experiment, optimum conditions of synthesis were as follows: the ratio of FeSO4.7H2O/diatomite in weight was 43/1, the reaction time is 1 h and the reaction temperature is 55 degrees C. By wastewater treatment experiment, it was found that the synthetic products showed good flocculation performance in the treatment of domestic sewage, the removal of COD was 80.00% and the removal of turbidity was 99.98%.

  20. Versatile Tandem Ring-Opening/Ring-Closing Metathesis Polymerization: Strategies for Successful Polymerization of Challenging Monomers and Their Mechanistic Studies.

    PubMed

    Park, Hyeon; Kang, Eun-Hye; Müller, Laura; Choi, Tae-Lim

    2016-02-24

    Tandem ring-opening/ring-closing metathesis (RO/RCM) results in extremely fast living polymerization; however, according to previous reports, only monomers containing certain combinations of cycloalkenes, terminal alkynes, and nitrogen linkers successfully underwent tandem polymerization. After examining the polymerization pathways, we proposed that the relatively slow intramolecular cyclization might lead to competing side reactions such as intermolecular cross metathesis reactions to form inactive propagating species. Thus, we developed two strategies to enhance tandem polymerization efficiency. First, we modified monomer structures to accelerate tandem RO/RCM cyclization by enhancing the Thorpe-Ingold effect. This strategy increased the polymerization rate and suppressed the chain transfer reaction to achieve controlled polymerization, even for challenging syntheses of dendronized polymers. Alternatively, reducing the reaction concentration facilitated tandem polymerization, suggesting that the slow tandem RO/RCM cyclization step was the main reason for the previous failure. To broaden the monomer scope, we used monomers containing internal alkynes and observed that two different polymer units with different ring sizes were produced as a result of nonselective α-addition and β-addition on the internal alkynes. Thorough experiments with various monomers with internal alkynes suggested that steric and electronic effects of the alkyne substituents influenced alkyne addition selectivity and the polymerization reactivity. Further polymerization kinetics studies revealed that the rate-determining step of monomers containing certain internal alkynes was the six-membered cyclization step via β-addition, whereas that for other monomers was the conventional intermolecular propagation step, as observed in other chain-growth polymerizations. This conclusion agrees well with all those polymerization results and thus validates our strategies.

  1. The Sohagpur Coalfield Project - A collaborative study of potential coking coal resources by the Geological Survey of India and the U.S. Geological Survey

    USGS Publications Warehouse

    Milici, Robert C.; Mukhopadhyay, Abhijit; Warwick, Peter D.; Adhikari, S.; Landis, Edwin R.; Mukhopadhyay, S.K.; Ghose, Ajoy K.; Bose, L.K.

    2003-01-01

    The Geological Survey of India (GSI), Coal Wing, and the U.S. Geological Survey (USGS), Energy Resources Team, conducted a collaborative study of the potential for coking coal resources within the Sohagpur coalfield, Madhya Pradesh, India from 1995 to 2001. The coalfield is located within an extensional basin that contains Permian- and Triassic-age strata of the Gondwana Supergroup (Figs. 1 and 2). The purposes of the study were to perform a synthesis of previous work and. an integrated analysis of the basin of deposition with particular emphasis on the regional stratigraphy and depositional environments of the coal-bearing strata, the geologic structure of the basin, and the geochemistry of the coal in order to understand the geologic controls on the distribution of coking coals within the basin. The results of this study have been published previously (Mukhopadhyay and others, 2001a, b), and this paper provides a general overview of our findings.

  2. Diverse Bacteria with Lignin Degrading Potentials Isolated from Two Ranks of Coal

    PubMed Central

    Wang, Lu; Nie, Yong; Tang, Yue-Qin; Song, Xin-Min; Cao, Kun; Sun, Li-Zhu; Wang, Zhi-Jian; Wu, Xiao-Lei

    2016-01-01

    Taking natural coal as a “seed bank” of bacterial strains able to degrade lignin that is with molecular structure similar to coal components, we isolated 393 and 483 bacterial strains from a meager lean coal sample from Hancheng coalbed and a brown coal sample from Bayannaoer coalbed, respectively, by using different media. Statistical analysis showed that isolates were significantly more site-specific than medium-specific. Of the 876 strains belonging to 27 genera in Actinobacteria, Firmicutes, and Proteobacteria, 612 were positive for lignin degradation function, including 218 strains belonging to 35 species in Hancheng and 394 strains belonging to 19 species in Zhongqi. Among them, the dominant lignin-degrading strains were Thauera (Hancheng), Arthrobacter (Zhongqi) and Rhizobium (both). The genes encoding the laccases- or laccase-like multicopper oxidases, key enzymes in lignin production and degradation, were detected in three genera including Massila for the first time, which was in high expression by real time PCR (qRT-PCR) detection, confirming coal as a good seed bank. PMID:27667989

  3. Effects of Sediment Containing Coal Ash from the Kingston Ash Release on Embryo-Larval Development in the Fathead Minnow, Pimephales promelas (Rafinesque, 1820)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Greeley Jr, Mark Stephen; Elmore, Logan R; McCracken, Kitty

    2014-01-01

    The largest environmental release of coal ash in U.S. history occurred in December 2008 with the failure of a retention structure at the Tennessee Valley Authority (TVA) Kingston Fossil Plant in East Tennessee. A byproduct of coal-burning power plants, coal ash is enriched in metals and metalloids such as selenium and arsenic with known toxicity to fish including embryonic and larval stages. The effects of contact exposure to sediments containing up to 78 % coal ash from the Kingston spill on the early development of fish embryos and larvae were examined in 7-day laboratory tests with the fathead minnow (Pimephalesmore » promelas). No significant effects were observed on hatching success, incidences of gross developmental abnormalities, or embryo-larval survival. Results suggest that direct exposures to sediment containing residual coal ash from the Kingston ash release may not present significant risks to fish eggs and larvae in waterways affected by the spill.« less

  4. Syntheses, structures and properties of polycarbosilanes formed directly by polymerization of Alkenylsilanes

    NASA Technical Reports Server (NTRS)

    Masnovi, John; Bu, Xin Y.; Beyene, Kassahun; Heimann, Paula; Kacik, Terrence; Andrist, A. Harry; Hurwitz, Frances I.

    1993-01-01

    Vinylsilane polymerizes to form predominantly a carbosilane polymer using dimethyltitanocene catalyst. This is in contrast to alkylsilanes, which afford polysilanes under the same conditions. The mechanism of polymerization of alkenylsilanes has been shown to be fundamentally different from that for the polymerization of alkylsilanes. The silyl substitute apparently activates a double bond to participate in a number of polymerization processes in this system, particularly hydrosilation. Isotopic labeling indicates the involvement of silametallocyclic intermediates, accompanied by extensive nuclear rearrangement. Polymers and copolymers derived from alkenylsilanes have relatively high char yields even for conditions which afford low molecular weight distributions. Formation of crystalline beta-SiC is optimum for a copolymer of an alkylsilane and an alkenylsilane having a silane/carbosilane backbone ratio of 85/15 and a C/Si ratio of 1.3/1.

  5. Geology and mineral resources of the Mud Springs Ranch Quadrangle, Sweetwater County, Wyoming

    USGS Publications Warehouse

    Roehler, Henry W.

    1979-01-01

    The Mud Springs Ranch quadrangle occupies an area of 56 mF (square miles) on the southeast flank of the Rock Springs uplift in southwestern Wyoming. The climate is arid and windy. The landscape is mostly poorly vegetated and consists of north-trending ridges and valleys that are dissected by dry drainages. Sedimentary rocks exposed in the quadrangle are 5,400 ft (feet) thick and are mostly gray sandstone, siltstone, and shale, gray and brown carbonaceous shale, and thin beds of coal. They compose the Blair, Rock Springs, Ericson, Almond, and Lewis Formations of Cretaceous age and the Fort Union Formation of Paleocene age. The structure is mostly homoclinal, having southeast dips of 5?-12? in the northern part of the quadrangle, but minor plunging folds and one small fault are present in the southern part of the quadrangle. Three coal beds in the Fort Union Formation and 15 coal beds in the Almond Formation exceed 2.5 ft in thickness, are under less than 3,000 ft of overburden, and are potentially minable. Geographic stratigraphic, and resource data are present for each bed of minable coal. The total minable coal resources are estimated to be about 283 million short tons. Nine coal and rock samples from outcrops were analyzed to determine their quality and chemical composition. Four dry oil and gas test wells have been drilled within the quadrangle area, but structurally controlled stratigraphic-trap prospects remain untested.

  6. Applications of polymeric micelles with tumor targeted in chemotherapy

    NASA Astrophysics Data System (ADS)

    Ding, Hui; Wang, Xiaojun; Zhang, Song; Liu, Xinli

    2012-11-01

    Polymeric micelles (PMs) have gained more progress as a carrier system with the quick development of biological and nanoparticle techniques. In particular, PMs with smart targeting can deliver anti-cancer drugs directly into tumor cells at a sustained rate. PMs with core-shell structure (with diameters of 10 100 nm) have been prepared by a variety of biodegradable and biocompatible polymers via a self-assembly process. The preparation of polymeric micelles with stimuli-responsive block copolymers or modification of target molecules on polymeric micelles' surface are able to significantly improve the efficiency of drug delivery. Polymeric micelles, which have been considered as a novel promising drug carrier for cancer therapeutics, are rapidly evolving and being introduced in an attempt to overcome several limitations of traditional chemotherapeutics, including water solubility, tumor-specific accumulation, anti-tumor efficacy, and non-specific toxicity. This review describes the preparation of polymeric micelles and the targeted modification which greatly enhance the effects of chemotherapeutic agents.

  7. An in situ occurrence of coal balls in the Amburgy coal bed, Pikeville Formation (Duckmantian), central Appalachian Basin, USA

    USGS Publications Warehouse

    Greb, S.F.; Eble, C.F.; Chesnut, D.R.; Phillips, T.L.; Hower, J.C.

    1999-01-01

    Carbonate concretions containing permineralized peat, commonly called coal balls, were encountered in the Amburgy coal, a generally low-ash (9.4%), but commonly high-sulfur (3.6%), Middle Pennsylvanian coal of the Eastern Kentucky Coal Field. These are the first coal balls from the Amburgy coal, and one of only a few reported occurrences from the central Appalachian Basin. The coal balls occur in the upper part of the coal, between two paleochannel cut-outs at the top of the Pikeville Formation, and immediately beneath a scour with a marine fossil lag at the base of the Kendrick Shale Member, Hyden Formation. The coal is thickest (1.3 m) in a narrow (<300 m), elongate depression between the bounding paleochannels, and thins toward the occurrence of coal balls. Total biovolume as measured from acetate peels of coal balls indicates cordaites or lycopsid (36.1% each) dominance. Vertical sampling through one coal-ball aggregate shows zoning from a lower cordaites-dominant (88.7%) assemblage, to a middle, degraded, sphenopsid-rich assemblage, to an upper lycopsid-dominant (88.6%) assemblage. Beneath the coal balls, palynologic and petrographic analyses indicate the basal and middle portions of the bed are dominated by arborescent lycopsid spores and cordaites pollen, and by vitrinite macerals. The top part of the bed, above the coal balls, contains increased intertinite macerals, increased percentages of small fern spores, and variable ash yield (5-21%). Thickening of the Amburgy coal along a structural low, in combination with basal high-ash yields, vitrinite-dominance, and heterogenous palynoflora, indicate paleotopographic control on initial peat accumulation. Abundant lycopsid spores in the basal and middle part of the coal reflect rheotrophic conditions consistent with accumulation in a paleotopographic depression. Apparent zonation preserved in one of the coal-ball masses may document plant successions in response to flooding. Similar percentages of cordaites and lycopods, respectively, in the zones above and below the degraded incursion interval reflect development of a mixed, successional pattern in response to the flooding. Coal-ball formation may have been facilitated by channeling along the Kendrick ravinement, within a paleotopographic depression, at the split margin of the Amburgy peat, either through direct transmittal of carbonates and marine waters into the peat, or through degassing of the peat beneath the scour.

  8. Relationship between Eu{sup 3+} reduction and glass polymeric structure in Al{sub 2}O{sub 3}-modified borate glasses under air atmosphere

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jiao, Qing; Yu, Xue; Xu, Xuhui

    2013-06-15

    The reduction of Eu{sup 3+} to Eu{sup 2+} is realized efficiently in Eu{sub 2}O{sub 3}-doped borate glasses prepared under air condition by melting-quenching method. Luminescent spectra show an increasing tendency of Eu{sup 2+} emission with increasing Al{sub 2}O{sub 3} concentration in B{sub 2}O{sub 3}–Na{sub 2}O glasses. It is interesting that significant enhancement appeared of Eu{sup 2+} luminescence in the Al{sub 2}O{sub 3}-rich sample comparing to the samples of Al{sub 2}O{sub 3} less than 6 mol%. FTIR and Raman scattering measurements indicated that some new vibration modes assigned to the low-polymerized structure groups decomposed from the slight Al{sub 2}O{sub 3} dopantmore » samples. These results demonstrated that the polymerization of the glass structure decreased with increasing incorporation of Al{sub 2}O{sub 3} into the borate glasses, linking to the efficiency of Eu{sup 3+} self-reduction in air at high temperature. - graphical abstract: A novel europium valence reduction phenomenon occurred in Al{sub 2}O{sub 3} modified borate glasses, FTIR and Raman measurements revealed that high polymeric groups were destroyed to low polymery structures with Al{sub 2}O{sub 3} addition. - Highlights: • The efficient reduction of Eu{sup 3+} to Eu{sup 2+} is observed in the B{sub 2}O{sub 3}–Na{sub 2}O glasses. • Eu{sup 2+} luminescence is significant enhanced in the Al{sub 2}O{sub 3}-rich glasses. • The introduction of Al{sub 2}O{sub 3} changed the network structure of the borate glasses. • High polymeric borate groups in the glass matrix may be destroyed to the lower ones.« less

  9. Novel organic LED structures based on a highly conductive polymeric photonic crystal electrode.

    PubMed

    Petti, Lucia; Rippa, Massimo; Capasso, Rossella; Nenna, Giuseppe; Del Mauro, Anna De Girolamo; Maglione, Maria Grazia; Minarini, Carla

    2013-08-09

    In this work we demonstrate the possibility to realize a novel unconventional ITO-free organic light emitting diode (OLED) utilizing a photonic polymeric electrode. Combining electron beam lithography and a plasma etching process to partially structure the highly conductive poly(3,4 ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) it is possible to realize an embedded photonic crystal (PC) structure. The realized PC-anode drastically reduces the light trapped in the OLED, demonstrating the possibility to eliminate further process stages and making it easier to use this technology even on rollable and flexible substrates.

  10. Novel organic LED structures based on a highly conductive polymeric photonic crystal electrode

    NASA Astrophysics Data System (ADS)

    Petti, Lucia; Rippa, Massimo; Capasso, Rossella; Nenna, Giuseppe; De Girolamo Del Mauro, Anna; Grazia Maglione, Maria; Minarini, Carla

    2013-08-01

    In this work we demonstrate the possibility to realize a novel unconventional ITO-free organic light emitting diode (OLED) utilizing a photonic polymeric electrode. Combining electron beam lithography and a plasma etching process to partially structure the highly conductive poly(3,4 ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) it is possible to realize an embedded photonic crystal (PC) structure. The realized PC-anode drastically reduces the light trapped in the OLED, demonstrating the possibility to eliminate further process stages and making it easier to use this technology even on rollable and flexible substrates.

  11. Band structure of cavity-type hypersonic phononic crystals fabricated by femtosecond laser-induced two-photon polymerization

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rakhymzhanov, A. M.; Utegulov, Z. N., E-mail: zhutegulov@nu.edu.kz, E-mail: fytas@mpip-mainz.mpg.de; Optics Laboratory, National Laboratory Astana, Nazarbayev University, Astana 10000

    2016-05-16

    The phononic band diagram of a periodic square structure fabricated by femtosecond laser pulse-induced two photon polymerization is recorded by Brillouin light scattering (BLS) at hypersonic (GHz) frequencies and computed by finite element method. The theoretical calculations along the two main symmetry directions quantitatively capture the band diagrams of the air- and liquid-filled structure and moreover represent the BLS intensities. The theory helps identify the observed modes, reveals the origin of the observed bandgaps at the Brillouin zone boundaries, and unravels direction dependent effective medium behavior.

  12. Unmanned aerial vehicles for the assessment and monitoring of environmental contamination: An example from coal ash spills.

    PubMed

    Messinger, Max; Silman, Miles

    2016-11-01

    Unmanned aerial vehicles (UAVs) offer new opportunities to monitor pollution and provide valuable information to support remediation. Their low-cost, ease of use, and rapid deployment capability make them ideal for environmental emergency response. Here we present a UAV-based study of the third largest coal ash spill in the United States. Coal ash from coal combustion is a toxic industrial waste material present worldwide. Typically stored in settling ponds in close proximity to waterways, coal ash poses significant risk to the environment and drinking water supplies from both chronic contamination of surface and ground water and catastrophic pond failure. We sought to provide an independent estimate of the volume of coal ash and contaminated water lost during the rupture of the primary coal ash pond at the Dan River Steam Station in Eden, NC, USA and to demonstrate the feasibility of using UAVs to rapidly respond to and measure the volume of spills from ponds or containers that are open to the air. Using structure-from-motion (SfM) imagery analysis techniques, we reconstructed the 3D structure of the pond bottom after the spill, used historical imagery to estimate the pre-spill waterline, and calculated the volume of material lost. We estimated a loss of 66,245 ± 5678 m 3 of ash and contaminated water. The technique used here allows rapid response to environmental emergencies and quantification of their impacts at low cost, and these capabilities will make UAVs a central tool in environmental planning, monitoring, and disaster response. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Heat and mass transfer at gas-phase ignition of grinded coal layer by several metal particles heated to a high temperature

    NASA Astrophysics Data System (ADS)

    Glushkov, D. O.; Kuznetsov, G. V.; Strizhak, P. A.

    2017-07-01

    Characteristics of gas-phase ignition of grinded brown coal (brand 2B, Shive-Ovoos deposit in Mongolia) layer by single and several metal particles heated to a high temperature (above 1000 K) have been investigated numerically. The developed mathematical model of the process takes into account the heating and thermal decomposition of coal at the expense of the heat supplied from local heat sources, release of volatiles, formation and heating of gas mixture and its ignition. The conditions of the joint effect of several hot particles on the main characteristic of the process-ignition delay time are determined. The relation of the ignition zone position in the vicinity of local heat sources and the intensity of combustible gas mixture warming has been elucidated. It has been found that when the distance between neighboring particles exceeds 1.5 hot particle size, an analysis of characteristics and regularities of coal ignition by several local heat sources can be carried out within the framework of the model of "single metal particle / grinded coal / air". Besides, it has been shown with the use of this model that the increase in the hot particle height leads, along with the ignition delay time reduction, to a reduction of the source initial temperatures required for solid fuel ignition. At an imperfect thermal contact at the interface hot particle / grinded coal due to the natural porosity of the solid fuel structure, the intensity of ignition reduces due to a less significant effect of radiation in the area of pores on the heat transfer conditions compared to heat transfer by conduction in the near-surface coal layer without regard to its heterogeneous structure.

  14. Characterizing coal beds in western Kentucky with the Al-La-Sc coherent triad

    USGS Publications Warehouse

    Chyi, L.L.; Medlin, J.H.

    1996-01-01

    Cyclic sedimentation and lateral facies changes make coal bed correlations inconclusive and difficult. This uncertainty can be further complicated if a coal basin has been structurally deformed. Coal macerals can be studied to indicate the nature and degree of coalification. Their use in coal bed correlation, however, is limited. Most of the trace elements and their ratios that have been studied show significant within-bed lateral and stratigraphic variations, and thus are not effective in correlating coal beds regionally. Geochemically coherent groups of elements, such as rare earth elements (REE) and platinum group elements (PGE), appear to be highly differentiated in coal-forming environments. Geochemical coherent elemental triads appear to be useful for coal bed identification or fingerprinting. The best triad which was demonstrated to be effective in coal bed characterization in western Kentucky, is that of Al, La and Sc. These three elements are highly correlated with one another and they can be determined accurately and simultaneously with instrumental neutron activation analysis (INAA). The elemental triad Al-La-Sc is used to identify and fingerprint three key coal beds in western Kentucky: the Springfield (western Kentucky No. 9), the Davis (western Kentucky No. 6), and the Mining City and Dawson Springs are both considered to be the No. 4 coal bed in western Kentucky). Four distinct groupings can be recognized by use of the Al-La-Sc triad. The Dawson Springs coals have the highest Al/(La + Sc) ratios, followed by the Springfield, the Davis and the Mining City. The Mining City coal bed generally has the highest La/Sc ratio. However, the Dawson Springs is not correlated with the Mining City using the triad analysis, even though they have reportedly similar stratigraphic positions in the western Kentucky coal basin. The Al-La-Sc triad appears to be effective in discriminating between the Springfield and the Davis coal beds throughout the entire Illinois Basin. Furthermore, the range of concentration variation of the AL-La-Sc triad suggests individual groupings of the No. 4 coal in western Kentucky. In addition to characterizing these coal beds, the Al-La-Sc triad may be used to confirm stratigraphic correlations.

  15. Installing heterobimetallic cobalt–aluminum single sites on a metal organic framework support

    DOE PAGES

    Thompson, Anthony B.; Pahls, Dale R.; Bernales, Varinia; ...

    2016-08-22

    Here, a heterobimetallic cobalt-aluminum complex was immobilized onto the metal organic framework NU-1000 using a simple solution-based deposition procedure. Characterization data are consistent with a maximum loading of a single Co-Al complex per Zr 6 node of NU-1000. Furthermore, the data support that the Co-Al bimetallic complex is evenly distributed throughout the NU-1000 particle, binds covalently to the Zr6 nodes, and occupies the NU-1000 apertures with the shortest internode distances (~8.5 Å). Heating the anchored Co-Al complex on NU-1000 at 300 °C for 1 h in air completely removes the organic ligand of the complex without affecting the structural integritymore » of the MOF support. We propose that a Co-Al oxide cluster is formed in place of the anchored complex in NU-1000 during heating. Collectively, the results suggest that well-defined heterobimetallic complexes can be effective precursors for installing two different metals simultaneously onto a MOF support. The CoAl-functionalized NU-1000 samples catalyze the oxidation of benzyl alcohol to benzaldehyde with tert-butyl hydroperoxide as a stoichiometric oxidant. Density functional theory calculations were performed to elucidate the detailed structures of the Co-Al active sites on the Zr 6-nodes, and a Co-mediated catalytic mechanism is proposed.« less

  16. Simulation Experiment and Acoustic Emission Study on Coal and Gas Outburst

    NASA Astrophysics Data System (ADS)

    Li, Hui; Feng, Zengchao; Zhao, Dong; Duan, Dong

    2017-08-01

    A coal and gas outburst is an extreme hazard in underground mining. The present paper conducts a laboratory simulation of a coal and gas outburst combined with acoustic emission analysis. The experiment uses a three-dimensional stress loading system and a PCI-2 acoustic emission monitoring system. Furthermore, the development of a coal and gas outburst is numerically studied. The results demonstrate that the deformation and failure of a coal sample containing methane under three-dimensional stress involves four stages: initial compression, elastic deformation, plastic deformation and failure. The development of internal microscale fractures within a coal sample containing methane is reflected by the distribution of acoustic emission events. We observed that the deformation and failure zone for a coal sample under three-dimensional stress has an ellipsoid shape. Primary acoustic emission events are generated at the weak structural surface that compresses with ease due to the external ellipsoid-shaped stress. The number of events gradually increases until an outburst occurs. A mathematical model of the internal gas pressure and bulk stress is established through an analysis of the internal gas pressure and bulk stress of a coal sample, and it is useful for reproducing experimental results. The occurrence of a coal and gas outburst depends not only on the in situ stress, gas pressure and physical and mechanical characteristics of the coal mass but also on the free weak surface of the outburst outlet of the coal mass. It is more difficult for an outburst to occur from a stronger free surface.

  17. The national coal-resources data system of the U.S. geological survey

    USGS Publications Warehouse

    Carter, M.D.

    1976-01-01

    The National Coal Resources Data System (NCRDS) was designed by the U.S. Geological Survey (USGS) to meet the increasing demands for rapid retrieval of information on coal location, quantity, quality, and accessibility. An interactive conversational query system devised by the USGS retrieves information from the data bank through a standard computer terminal. The system is being developed in two phases. Phase I, which currently is available on a limited basis, contains published areal resource and chemical data. The primary objective of this phase is to retrieve, calculate, and tabulate coal-resource data by area on a local, regional, or national scale. Factors available for retrieval include: state, county, quadrangle, township, coal field, coal bed, formation, geologic age, source and reliability of data, and coal-bed rank, thickness, overburden, and tonnage, or any combinations of variables. In addition, the chemical data items include individual values for proximate and ultimate analyses, BTU value, and several other physical and chemical tests. Information will be validated and deleted or updated as needed. Phase II is being developed to store, retrieve, and manipulate basic point source coal data (e.g., field observations, drill-hole logs), including geodetic location; bed thickness; depth of burial; moisture; ash; sulfur; major-, minor-, and trace-element content; heat value; and characteristics of overburden, roof rocks, and floor rocks. The computer system may be used to generate interactively structure-contour or isoline maps of the physical and chemical characteristics of a coal bed or to calculate coal resources. ?? 1976.

  18. Dense Carbon Monoxide to 160 GPa: Stepwise Polymerization to Two-Dimensional Layered Solid

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ryu, Young-Jay; Kim, Minseob; Lim, Jinhyuk

    Carbon monoxide (CO) is the first molecular system found to transform into a nonmolecular “polymeric” solid above 5.5 GPa, yet been studied beyond 10 GPa. Here, we show a series of pressure-induced phase transformations in CO to 160 GPa: from a molecular solid to a highly colored, low-density polymeric phase I to translucent, high-density phase II to transparent, layered phase III. The properties of these phases are consistent with those expected from recently predicted 1D P2 1/m, 3D I2 12 12 1, and 2D Cmcm structures, respectively. Thus, the present results advocate a stepwise polymerization of CO triple bonds tomore » ultimately a 2D singly bonded layer structure with an enhanced ionic character.« less

  19. Advanced power assessment for Czech lignite. Task 3.6, Volume 1

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sondreal, E.A.; Mann, M.D.; Weber, G.W.

    1995-12-01

    The US has invested heavily in research, development, and demonstration of efficient and environmentally acceptable technologies for the use of coal. The US has the opportunity to use its leadership position to market a range of advanced coal-based technologies internationally. For example, coal mining output in the Czech Republic has been decreasing. This decrease in demand can be attributed mainly to the changing structure of the Czech economy and to environmental constraints. The continued production of energy from indigenous brown coals is a major concern for the Czech Republic. The strong desire to continue to use this resource is amore » challenge. The Energy and Environmental Research Center undertook two major efforts recently. One effort involved an assessment of opportunities for commercialization of US coal technologies in the Czech Republic. This report is the result of that effort. The technology assessment focused on the utilization of Czech brown coals. These coals are high in ash and sulfur, and the information presented in this report focuses on the utilization of these brown coals in an economically and environmentally friendly manner. Sections 3--5 present options for utilizing the as-mined coal, while Sections 6 and 7 present options for upgrading and generating alternative uses for the lignite. Contents include Czech Republic national energy perspectives; powering; emissions control; advanced power generation systems; assessment of lignite-upgrading technologies; and alternative markets for lignite.« less

  20. The accessibility of etheno-nucleotides to collisional quenchers and the nucleotide cleft in G- and F-actin.

    PubMed Central

    Root, D. D.; Reisler, E.

    1992-01-01

    Recent publication of the atomic structure of G-actin (Kabsch, W., Mannherz, H. G., Suck, D., Pai, E. F., & Holmes, K. C., 1990, Nature 347, 37-44) raises questions about how the conformation of actin changes upon its polymerization. In this work, the effects of various quenchers of etheno-nucleotides bound to G- and F-actin were examined in order to assess polymerization-related changes in the nucleotide phosphate site. The Mg(2+)-induced polymerization of actin quenched the fluorescence of the etheno-nucleotides by approximately 20% simultaneously with the increase in light scattering by actin. A conformational change at the nucleotide binding site was also indicated by greater accessibility of F-actin than G-actin to positively, negatively, and neutrally charged collisional quenchers. The difference in accessibility between G- and F-actin was greatest for I-, indicating that the environment of the etheno group is more positively charged in the polymerized form of actin. Based on calculations of the change in electric potential of the environment of the etheno group, specific polymerization-related movements of charged residues in the atomic structure of G-actin are suggested. The binding of S-1 to epsilon-ATP-G-actin increased the accessibility of the etheno group to I- even over that in Mg(2+)-polymerized actin. The quenching of the etheno group by nitromethane was, however, unaffected by the binding of S-1 to actin. Thus, the binding of S-1 induces conformational changes in the cleft region of actin that are different from those caused by Mg2+ polymerization of actin.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1304380

  1. Single chain technology: Toward the controlled synthesis of polymer nanostructures

    NASA Astrophysics Data System (ADS)

    Lyon, Christopher

    A technique for fabricating advanced polymer nanostructures enjoying recent popularity is the collapse or folding of single polymer chains in highly dilute solution mediated by intramolecular cross-linking. We term the resultant structures single-chain nanoparticles (SCNP). This technique has proven particularly valuable in the synthesis of nanomaterials on the order of 5 -- 20 nm. Many different types of covalent and non-covalent chemistries have been used to this end. This dissertation investigates the use of so-called single-chain technology to synthesize nanoparticles using modular techniques that allow for easy incorporation of functionality or special structural or characteristic features. Specifically, the synthesis of linear polymers functionalized with pendant monomer units and the subsequent intramolecular polymerization of these monomer units is discussed. In chapter 2, the synthesis of SCNP using alternating radical polymerization is described. Polymers functionalized with pendant styrene and stilbene groups are synthesized via a modular post-polymerization Wittig reaction. These polymers were exposed to radical initiators in the presence (and absence) of maleic anhydride and other electron deficient monomers in order to form intramolecular cross-links. Chapter 3 discusses templated acyclic diene metathesis (ADMET) polymerization using single-chain technology, starting with the controlled ring-opening polymerization of a glycidyl ether functionalized with an ADMET monomer. This polymer was then exposed to Grubbs' catalyst to polymerize the ADMET monomer units. The ADMET polymer was hydrolytically cleaved from the template and separated. Upon characterization, it was found that the daughter ADMET polymer had a similar degree of polymerization, but did not retain the low dispersity of the template. Chapter 4 details the synthesis of aldehyde- and diol-functionalized polymers toward the synthesis of SCNP containing dynamic, acid-degradable acetal cross-links. SCNP fabrication with these materials is beyond the scope of this dissertation.

  2. Bioactive Polymeric Materials for Tissue Repair

    PubMed Central

    Bienek, Diane R.; Tutak, Wojtek; Skrtic, Drago

    2017-01-01

    Bioactive polymeric materials based on calcium phosphates have tremendous appeal for hard tissue repair because of their well-documented biocompatibility. Amorphous calcium phosphate (ACP)-based ones additionally protect against unwanted demineralization and actively support regeneration of hard tissue minerals. Our group has been investigating the structure/composition/property relationships of ACP polymeric composites for the last two decades. Here, we present ACP’s dispersion in a polymer matrix and the fine-tuning of the resin affects the physicochemical, mechanical, and biological properties of ACP polymeric composites. These studies illustrate how the filler/resin interface and monomer/polymer molecular structure affect the material’s critical properties, such as ion release and mechanical strength. We also present evidence of the remineralization efficacy of ACP composites when exposed to accelerated acidic challenges representative of oral environment conditions. The utility of ACP has recently been extended to include airbrushing as a platform technology for fabrication of nanofiber scaffolds. These studies, focused on assessing the feasibility of incorporating ACP into various polymer fibers, also included the release kinetics of bioactive calcium and phosphate ions from nanofibers and evaluate the biorelevance of the polymeric ACP fiber networks. We also discuss the potential for future integration of the existing ACP scaffolds into therapeutic delivery systems used in the precision medicine field. PMID:28134776

  3. Polymeric micelles for ocular drug delivery: From structural frameworks to recent preclinical studies.

    PubMed

    Mandal, Abhirup; Bisht, Rohit; Rupenthal, Ilva D; Mitra, Ashim K

    2017-02-28

    Effective intraocular drug delivery poses a major challenge due to the presence of various elimination mechanisms and physiological barriers that result in low ocular bioavailability after topical application. Over the past decades, polymeric micelles have emerged as one of the most promising drug delivery platforms for the management of ocular diseases affecting the anterior (dry eye syndrome) and posterior (age-related macular degeneration, diabetic retinopathy and glaucoma) segments of the eye. Promising preclinical efficacy results from both in-vitro and in-vivo animal studies have led to their steady progression through clinical trials. The mucoadhesive nature of these polymeric micelles results in enhanced contact with the ocular surface while their small size allows better tissue penetration. Most importantly, being highly water soluble, these polymeric micelles generate clear aqueous solutions which allows easy application in the form of eye drops without any vision interference. Enhanced stability, larger cargo capacity, non-toxicity, ease of surface modification and controlled drug release are additional advantages with polymeric micelles. Finally, simple and cost effective fabrication techniques render their industrial acceptance relatively high. This review summarizes structural frameworks, methods of preparation, physicochemical properties, patented inventions and recent advances of these micelles as effective carriers for ocular drug delivery highlighting their performance in preclinical studies. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. A flexible, robust and antifouling asymmetric membrane based on ultra-long ceramic/polymeric fibers for high-efficiency separation of oil/water emulsions.

    PubMed

    Wang, Kui; Yiming, Wubulikasimu; Saththasivam, Jayaprakash; Liu, Zhaoyang

    2017-07-06

    Polymeric and ceramic asymmetric membranes have dominated commercial membranes for water treatment. However, polymeric membranes are prone to becoming fouled, while ceramic membranes are mechanically fragile. Here, we report a novel concept to develop asymmetric membranes based on ultra-long ceramic/polymeric fibers, with the combined merits of good mechanical stability, excellent fouling resistance and high oil/water selectivity, in order to meet the stringent requirements for practical oil/water separation. The ultra-long dimensions of ceramic nanofibers/polymeric microfibers endow this novel membrane with mechanical flexibility and robustness, due to the integrated and intertwined structure. This membrane is capable of separating oil/water emulsions with high oil-separation efficiency (99.9%), thanks to its nanoporous selective layer made of ceramic nanofibers. Further, this membrane also displays superior antifouling properties due to its underwater superoleophobicity and ultra-low oil adhesion of the ceramic-based selective layer. This membrane exhibits high water permeation flux (6.8 × 10 4 L m -2 h -1 bar -1 ) at low operation pressures, which is attributed to its 3-dimensional (3D) interconnected fiber-based structure throughout the membrane. In addition, the facile fabrication process and inexpensive materials required for this membrane suggest its significant potential for industrial applications.

  5. Nanodusty plasma chemistry: a mechanistic and variational transition state theory study of the initial steps of silyl anion-silane and silylene anion-silane polymerization reactions.

    PubMed

    Bao, Junwei Lucas; Seal, Prasenjit; Truhlar, Donald G

    2015-06-28

    The growth of nanodusty particles, which is critical in plasma chemistry, physics, and engineering. The aim of the present work is to understand the detailed reaction mechanisms of early steps in this growth. The polymerization of neutral silane with the silylene or silyl anion, which eliminates molecular hydrogen with the formation of their higher homologues, governs the silicon hydride clustering in nanodusty plasma chemistry. The detailed mechanisms of these important polymerization reactions in terms of elementary reactions have not been proposed yet. In the present work, we investigated the initial steps of these polymerization reactions, i.e., the SiH4 + Si2H4(-)/Si2H5(-) reactions, and we propose a three-step mechanism, which is also applicable to the following polymerization steps. CM5 charges of all the silicon-containing species were computed in order to analyze the character of the species in the proposed reaction mechanisms. We also calculated thermal rate constant of each step using multi-structural canonical variational transition state theory (MS-CVT) with the small-curvature tunneling (SCT) approximation, based on the minimum energy path computed using M08-HX/MG3S electronic structure method.

  6. Research of a possibility of receiving sorbents for a sewage disposal from a wastage of coal preparation factory

    NASA Astrophysics Data System (ADS)

    Buyantuev, S. L.; Kondratenko, A. S.; Shishulkin, S. Y.; Stebenkova, Y. Y.; Khmelev, A. B.

    2017-05-01

    The paper presents the results of the studies of the structure and porosity of the coal cake processed by electric arc plasma. The main limiting factor in processing of coal cakes sorbents is their high water content. As a result of coal washing, the main share of water introduced into the cake falls on hard-hydrate and colloidal components. This makes impossible application of traditional processes of manufacturing from a cake of coal sorbents. Using the electric arc intensifies the processes of thermal activation of coal cakes associated with thermal shock, destruction and vapor-gas reactions occurring at the surfaces of the particles at an exposure temperature of up to 3000 °C, which increases the title product outlet (sorbent) and thereby reduces manufacturing costs and improves environmental performance. The investigation of the thermal activation zone is carried out in the plasma reactor chamber by thermal imaging method followed by mapping-and 3D-modeling of temperature fields. the most important physical and chemical properties of the sorbents from coal cake activated by plasma was studied. The obtained results showed the possibility of coal cake thermal activation by electric arc plasma to change its material composition, the appearance of porosity and associated sorption capacity applied for wastewater treatment.

  7. Pyrolytic carbon membranes containing silica: morphological approach on gas transport behavior

    NASA Astrophysics Data System (ADS)

    Park, Ho Bum; Lee, Sun Yong; Lee, Young Moo

    2005-04-01

    Pyrolytic carbon membrane containing silica (C-SiO 2) is a new-class material for gas separation, and in the present work we will deal with it in view of the morphological changes arising from the difference in the molecular structure of the polymeric precursors. The silica embedded carbon membranes were fabricated by a predetermined pyrolysis step using imide-siloxane copolymers (PISs) that was synthesized from benzophenone tetracarboxylic dianhydrides (BTDA), 4,4'-oxydianiline (ODA), and amine-terminated polydimethylsiloxane (PDMS). To induce different morphologies at the same chemical composition, the copolymers were prepared using one-step (preferentially a random segmented copolymer) sand two-step polymerization (a block segmented copolymer) methods. The polymeric precursors and their pyrolytic C-SiO 2 membranes were analyzed using thermal analysis, atomic force microscopy, and transmission electron microscopy, etc. It was found that the C-SiO 2 membrane derived from the random PIS copolymer showed a micro-structure containing small well-dispersed silica domains, whereas the C-SiO 2 membrane from the block PIS copolymer exhibited a micro-structure containing large silica domains in the continuous carbon matrix. Eventually, the gas transport through these C-SiO 2 membranes was significantly affected by the morphological changes of the polymeric precursors.

  8. Arabidopsis peroxidase-catalyzed copolymerization of coniferyl and sinapyl alcohols: kinetics of an endwise process.

    PubMed

    Demont-Caulet, Nathalie; Lapierre, Catherine; Jouanin, Lise; Baumberger, Stéphanie; Méchin, Valérie

    2010-10-01

    In order to determine the mechanism of the earlier copolymerization steps of two main lignin precursors, sinapyl (S) alcohol and coniferyl (G) alcohol, microscale in vitro oxidations were carried out with a PRX34 Arabidopsis thaliana peroxidase in the presence of H(2)O(2). This plant peroxidase was found to have an in vitro polymerization activity similar to the commonly used horseradish peroxidase. The selected polymerization conditions lead to a bulk polymerization mechanism when G alcohol was the only phenolic substrate available. In the same conditions, the presence of S alcohol at a 50/50 S/G molar ratio turned this bulk mechanism into an endwise one. A kinetics monitoring (size-exclusion chromatography and liquid chromatography-mass spectrometry) of the different species formed during the first 24h oxidation of the S/G mixture allowed sequencing the bondings responsible for oligomerization. Whereas G homodimers and GS heterodimers exhibit low reactivity, the SS pinoresinol structure act as a nucleating site of the polymerization through an endwise process. This study is particularly relevant to understand the impact of S units on lignin structure in plants and to identify the key step at which this structure is programmed. Copyright © 2010 Elsevier Ltd. All rights reserved.

  9. Occurrence and Speciation of Polymeric Chromium(III), Monomeric Chromium(III) and Chromium(VI) in Environmental Samples

    PubMed Central

    HU, LIGANG; CAI, YONG; JIANG, GUIBIN

    2016-01-01

    Laboratory experiments suggest that polymeric Cr(III) could exist in aqueous solution for a relative long period of time. However, the occurrence of polymeric Cr(III) has not been reported in environmental media due partially to the lack of method for speciating polymeric Cr. We observed an unknown Cr species during the course of study on speciation of Cr in the leachates of chromated-copper-arsenate (CCA)-treated wood. Efforts were made to identify structure of the unknown Cr species. Considering the forms of Cr existed in the CCA-treated woods, we mainly focused our efforts to determine if the unknown species were polymeric Cr(III), complex of Cr/As or complex of Cr with dissolved organic matter (DOM). In order to evaluate whether polymeric Cr(III) largely exist in wood leachates, high performance liquid chromatography coupled with inductively coupled mass spectrometry (HPLC-ICPMS was used) for simultaneous speciation of monomeric Cr(III), polymeric Cr(III), and Cr(VI). In addition to wood leachates where polymeric Cr (III) ranged from 39.1 to 67.4 %, occurrence of the unknown Cr species in other environmental matrices, including surface waters, tap and waste waters, was also investigated. It was found that polymeric Cr(III) could exist in environmental samples containing μg/L level of Cr, at a level up to 60% of total Cr, suggesting that polymeric Cr(III) could significantly exist in natural environments. Failure in quantifying polymeric Cr(III) would lead to the underestimation of total Cr and bias in Cr speciation. The environmental implication of the presence of polymeric Cr(III) species in the environment deserves further study. PMID:27156211

  10. Rational Use of Land Resource During the Implementation of Transportless System of Coal Strata Surface Mining

    NASA Astrophysics Data System (ADS)

    Gvozdkova, T.; Tyulenev, M.; Zhironkin, S.; Trifonov, V. A.; Osipov, Yu M.

    2017-01-01

    Surface mining and open pits engineering affect the environment in a very negative way. Among other pollutions that open pits make during mineral deposits exploiting, particular problem is the landscape changing. Along with converting the land into pits, surface mining is connected with pilling dumps that occupy large ground. The article describes an analysis of transportless methods of several coal seams strata surface mining, applied for open pits of South Kuzbass coal enterprises (Western Siberia, Russia). To improve land-use management of open pit mining enterprises, the characteristics of transportless technological schemes for several coal seams strata surface mining are highlighted and observed. These characteristics help to systematize transportless open mining technologies using common criteria that characterize structure of the bottom part of a strata and internal dumping schemes. The schemes of transportless systems of coal strata surface mining implemented in South Kuzbass are given.

  11. Structural analysis of geochemical samples by solid-state nuclear magnetic resonance spectrometry. Role of paramagnetic material

    USGS Publications Warehouse

    Vassallo, A.M.; Wilson, M.A.; Collin, P.J.; Oades, J.M.; Waters, A.G.; Malcolm, R.L.

    1987-01-01

    An examination of coals, coal tars, a fulvic acid, and soil fractions by solid-state 13C NMR spectrometry has demonstrated widely differing behavior regarding quantitative representation in the spectrum. Spin counting experiments on coal tars and the fulvic acid show that almost all the sample carbon is observed in both solution and solid-state NMR spectra. Similar experiments on two coals (a lignite and a bituminous coal) show that most (70-97%) of the carbon is observed; however, when the lignite is ion exchanged with 3% (w/w) Fe3+, the fraction of carbon observed drops to below 10%. In additional experiments signal intensity from soil samples is enhanced by a simple dithionite treatment. This is illustrated by 13C, 27Al, and 29Si solid-state NMR experiments on soil fractions. ?? 1987 American Chemical Society.

  12. Study on CO2 gasification reactivity and physical characteristics of biomass, petroleum coke and coal chars.

    PubMed

    Huo, Wei; Zhou, Zhijie; Chen, Xueli; Dai, Zhenghua; Yu, Guangsuo

    2014-05-01

    Gasification reactivities of six different carbonaceous material chars with CO2 were determined by a Thermogravimetric Analyzer (TGA). Gasification reactivities of biomass chars are higher than those of coke and coal chars. In addition, physical structures and chemical components of these chars were systematically tested. It is found that the crystalline structure is an important factor to evaluate gasification reactivities of different chars and the crystalline structures of biomass chars are less order than those of coke and coal chars. Moreover, initial gasification rates of these chars were measured at high temperatures and with relatively large particle sizes. The method of calculating the effectiveness factor η was used to quantify the effect of pore diffusion on gasification. The results show that differences in pore diffusion effects among gasification with various chars are prominent and can be attributed to different intrinsic gasification reactivities and physical characteristics of different chars. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. High temperature deformation of NiAl and CoAl

    NASA Technical Reports Server (NTRS)

    Nix, W. D.

    1982-01-01

    The high temperature mechanical properties of the aluminides are reviewed with respect to their potential as high temperature structural materials. It is shown that NiAl and CoAl are substantially stronger than the pure metals Ni and Co at high temperatures and approach the strength of some superalloys, particularly when those superalloys are tested in "weak" directions. The factors that limit and control the high temperature strengths of NiAl and CoAl are examined to provide a basis for the development of intermetallic alloys of this type.

  14. 30 CFR 77.1109 - Quantity and location of firefighting equipment.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    .... 77.1109 Section 77.1109 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS, SURFACE COAL MINES AND SURFACE WORK AREAS OF... paragraph (b) for each 2,500 square feet of floor space in a wooden or other flammable structure, or for...

  15. 30 CFR 77.1109 - Quantity and location of firefighting equipment.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    .... 77.1109 Section 77.1109 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS, SURFACE COAL MINES AND SURFACE WORK AREAS OF... paragraph (b) for each 2,500 square feet of floor space in a wooden or other flammable structure, or for...

  16. Structural and Functional Characteristics of Natural and Constructed Channels Draining a Reclaimed Mountaintop Removal and Valley Fill Coal Mine

    EPA Science Inventory

    Mountaintop removal and valley fill (MTR/VF) coal mining has altered the landscape of the Central Appalachian region in the USA. Among the changes are large-scale topographic recontouring, burial of headwater streams, and degradation of downstream water quality. The goals of our ...

  17. Integration of thermal digital 3D model and a MASW (Multichannel Analysis of Surface Wave) as a means of improving monitoring of spoil tip stability

    NASA Astrophysics Data System (ADS)

    Lewińska, Paulina; Matuła, Rafał; Dyczko, Artur

    2018-01-01

    Spoil tips are anthropogenic terrain structures built of leftover (coal) mining materials. They consist mostly of slate and sandstone or mudstone but also include coal and highly explosive coal dust. Coal soil tip fires cause an irreversible degradation to the environment. Government organizations notice the potential problem of spoil tip hazard and are looking for ways of fast monitoring of their temperature and inside structure. In order to test new monitoring methods an experimental was performed in the area of spoil tip of Lubelski Węgiel "Bogdanka" S.A. A survey consisted of creating a 3D discreet thermal model. This was done in order to look for potential fire areas. MASW (Multichannel analysis of surface wave) was done in order to find potential voids within the body of a tip. Existing data was digitalized and a 3D model of object's outside and inside was produced. This article provides results of this survey and informs about advantages of such an approach.

  18. Synthesis, characterization, and morphology study of poly(acrylamide-co-acrylic acid)-grafted-poly(styrene-co-methyl methacrylate) "raspberry"-shape like structure microgels by pre-emulsified semi-batch emulsion polymerization.

    PubMed

    Ramli, Ros Azlinawati; Hashim, Shahrir; Laftah, Waham Ashaier

    2013-02-01

    A novel microgels were polymerized using styrene (St), methyl methacrylate (MMA), acrylamide (AAm), and acrylic acid (AAc) monomers in the presence of N,N'-methylenebisacrylamide (MBA) cross-linker. Pre-emulsified monomer was first prepared followed by polymerizing monomers using semi-batch emulsion polymerization. Fourier Transform Infrared Spectroscopy (FTIR) and (1)H Nuclear Magnetic Resonance (NMR) were used to determine the chemical structure and to indentify the related functional group. Grafting and cross-linking of poly(acrylamide-co-acrilic acid)-grafted-poly(styrene-co-methyl methacrylate) [poly(AAm-co-AAc)-g-poly(St-co-MMA)] microgels are approved by the disappearance of band at 1300 cm(-1), 1200 cm(-1) and 1163 cm(-1) of FTIR spectrum and the appearance of CH peaks at 5.5-5.7 ppm in (1)H NMR spectrum. Scanning Electron Microscope (SEM) images indicated that poly(St-co-MMA) particle was lobed morphology coated by cross-linked poly(AAm-co-AAc) shell. Furthermore, SEM results revealed that poly(AAm-co-AAc)-g-poly(St-co-MMA) is composite particle that consist of "raspberry"-shape like structure core. Internal structures of the microgels showed homogeneous network of pores, an extensive interconnection among pores, thicker pore walls, and open network structures. Water absorbency test indicated that the sample with particle size 0.43 μm had lower equilibrium water content, % than the sample with particle size 7.39 μm. Copyright © 2012 Elsevier Inc. All rights reserved.

  19. Quantitative measurement of the near-field enhancement of nanostructures by two-photon polymerization.

    PubMed

    Geldhauser, Tobias; Kolloch, Andreas; Murazawa, Naoki; Ueno, Kosei; Boneberg, Johannes; Leiderer, Paul; Scheer, Elke; Misawa, Hiroaki

    2012-06-19

    The quantitative determination of the strength of the near-field enhancement in and around nanostructures is essential for optimizing and using these structures for applications. We combine the gaussian intensity distribution of a laser profile and two-photon-polymerization of SU-8 to a suitable tool for the quantitative experimental measurement of the near-field enhancement of a nanostructure. Our results give a feedback to the results obtained by finite-difference time-domain (FDTD) simulations. The structures under investigation are gold nanotriangles on a glass substrate with 85 nm side length and a thickness of 40 nm. We compare the threshold fluence for polymerization for areas of the gaussian intensity profile with and without the near-field enhancement of the nanostructures. The experimentally obtained value of the near-field intensity enhancement is 600 ± 140, independent of the laser power, irradiation time, and spot size. The FDTD simulation shows a pointlike maximum of 2600 at the tip. In a more extended area with an approximate size close to the smallest polymerized structure of 25 nm in diameter, we find a value between 800 and 600. Using our novel approach, we determine the threshold fluence for polymerization of the commercially available photopolymerizable resin SU-8 by a femtosecond laser working at a wavelength of 795 nm and a repetition rate of 82 MHz to be 0.25 J/cm(2) almost independent of the irradiation time and the laser power used. This finding is important for future applications of the method because it enables one to use varying laser systems.

  20. Method for making field-structured memory materials

    DOEpatents

    Martin, James E.; Anderson, Robert A.; Tigges, Chris P.

    2002-01-01

    A method of forming a dual-level memory material using field structured materials. The field structured materials are formed from a dispersion of ferromagnetic particles in a polymerizable liquid medium, such as a urethane acrylate-based photopolymer, which are applied as a film to a support and then exposed in selected portions of the film to an applied magnetic or electric field. The field can be applied either uniaxially or biaxially at field strengths up to 150 G or higher to form the field structured materials. After polymerizing the field-structure materials, a magnetic field can be applied to selected portions of the polymerized field-structured material to yield a dual-level memory material on the support, wherein the dual-level memory material supports read-and-write binary data memory and write once, read many memory.

  1. Changes in optical properties, chemistry, and micropore and mesopore characteristics of bituminous coal at the contact with dikes in the Illinois Basin

    USGS Publications Warehouse

    Mastalerz, Maria; Drobniak, A.; Schimmelmann, A.

    2009-01-01

    Changes in high-volatile bituminous coal (Pennsylvanian) near contacts with two volcanic intrusions in Illinois were investigated with respect to optical properties, coal chemistry, and coal pore structure. Vitrinite reflectance (Ro) increases from 0.62% to 5.03% within a distance of 5.5??m from the larger dike, and from 0.63% to 3.71% within 3.3??m from the small dike. Elemental chemistry of the coal shows distinct reductions in hydrogen and nitrogen content close to the intrusions. No trend was observed for total sulfur content, but decreases in sulfate content towards the dikes indicate thermochemical sulfate reduction (TSR). Contact-metamorphism has a dramatic effect on coal porosity, and microporosity in particular. Around the large dike, the micropore volume, after a slight initial increase, progressively decreases from 0.0417??cm3/g in coal situated 4.7??m from the intrusive contact to 0.0126??cm3/g at the contact. Strongly decreasing mesopore and micropore volumes in the altered zone, together with frequent cleat and fracture filling by calcite, indicate deteriorating conditions for both coalbed gas sorption and gas transmissibility. ?? 2008 Elsevier B.V. All rights reserved.

  2. Online SAXS investigations of polymeric hollow fibre membranes.

    PubMed

    Pranzas, P Klaus; Knöchel, Arndt; Kneifel, Klemens; Kamusewitz, Helmut; Weigel, Thomas; Gehrke, Rainer; Funari, Sérgio S; Willumeit, Regine

    2003-07-01

    Polymeric membranes are used in industrial and analytical separation techniques. In this study small-angle X-ray scattering (SAXS) with synchrotron radiation has been applied for in-situ characterisation during formation of polymeric membranes. The spinning of a polyetherimide (PEI) hollow fibre membrane was chosen for investigation of dynamic aggregation processes during membrane formation, because it allows the measurement of the dynamic equilibrium at different distances from the spinning nozzle. With this system it is possible to resolve structural changes in the nm-size range which occur during membrane formation on the time-scale of milliseconds. Integral structural parameters, like radius of gyration and pair-distance distribution, were determined. Depending on the chosen spinning parameters, e.g. the flow ratio between polymer solution and coagulant water, significant changes in the scattering curves have been observed. The data are correlated with the distance from the spinning nozzle in order to get information about the kinetics of membrane formation which has fundamental influence on structure and properties of the membrane.

  3. Synthesis and photocatalytic CO2 reduction performance of Cu2O/Coal-based carbon nanoparticle composites

    NASA Astrophysics Data System (ADS)

    Dedong, Zhang; Maimaiti, Halidan; Awati, Abuduheiremu; Yisilamu, Gunisakezi; Fengchang, Sun; Ming, Wei

    2018-05-01

    The photocatalytic reduction of CO2 into hydrocarbons provides a promising approach to overcome the challenges of environmental crisis and energy shortage. Here we fabricated a cuprous oxide (Cu2O) based composite photocatalyst consisting of Cu2O/carbon nanoparticles (CNPs). To prepare the CNPs, coal samples from Wucaiwan, Xinjiang, China, were first treated with HNO3, followed by hydrogen peroxide (H2O2) oxidation to strip nanocrystalline carbon from coal. After linking with oxygen-containing group such as hydroxyl, coal-based CNPs with sp2 carbon structure and multilayer graphene lattice structure were synthesized. Subsequently, the CNPs were loaded onto the surface of Cu2O nanoparticles prepared by in-situ reduction of copper chloride (CuCl2·2H2O). The physical properties and chemical structure of the Cu2O/CNPs as well as photocatalytic activity of CO2/H2O reduction into CH3OH were measured. The results demonstrate that the Cu2O/CNPs are composed of spherical particles with diameter of 50 nm and mesoporous structure, which are suitable for CO2 adsorption. Under illumination of visible light, electron-hole pairs are generated in Cu2O. Thanks to the CNPs, the fast recombination of electron-hole pairs is suppressed. The energy gradient formed on the surface of Cu2O/CNPs facilitates the efficient separation of electron-hole pairs for CO2 reduction and H2O oxidation, leading to enhanced photocatalytic activity.

  4. Pervaporation separation of ethanol-water mixtures using polyacrylic acid composite membranes

    DOEpatents

    Neidlinger, H.H.

    1985-05-07

    Synthetic, organic, polymeric membranes were prepared from polyacrylic acid salts for use with pervaporation apparatus in the separation of ehthanol-water mixtures. The polymeric material was prepared in dilute aqueous solution and coated onto a polysulfone support film, from which excess polymeric material was subsequently removed. Cross-links were then generated by limited exposure to toluene-2,4-diisocyanata solution, after which the prepared membrane was heat-cured. The resulting membrane structure showed selectivity in permeating water over a wide range of feed concentrations. 4 tabs.

  5. Pervaporation separation of ethanol-water mixtures using polyethylenimine composite membranes

    DOEpatents

    Neidlinger, H.H.; Schissel, P.O.; Orth, R.A.

    1985-06-19

    Synthetic, organic, polymeric membranes were prepared from polyethylenimine for use with pervaporation apparatus in the separation of ethanol-water mixtures. The polymeric material was prepared in dilute aqueous solution and coated onto a polysulfone support film, from which excess polymeric material was subsequently removed. Cross-links were then generated by limited exposure to toluene-2,4-diisocyanate solution, after which the prepared membrane was heat-cured. The resulting membrane structures showed high selectivity in permeating ethanol or water over a wide range of feed concentrations. 2 tabs.

  6. On-demand photoinitiated polymerization

    DOEpatents

    Boydston, Andrew J; Grubbs, Robert H; Daeffler, Chris; Momcilovic, Nebojsa

    2015-01-13

    Compositions and methods for adjustable lenses are provided. In some embodiments, the lenses contain a lens matrix material, a masking compound, and a prepolymer. The lens matrix material provides structure to the lens. The masking compound is capable of blocking polymerization or crosslinking of the prepolymer, until photoisomerization of the compound is triggered, and the compound is converted from a first isomer to a second isomer having a different absorption profile. The prepolymer is a composition that can undergo a polymerization or crosslinking reaction upon photoinitiation to alter one or more of the properties of the lenses.

  7. On-demand photoinitiated polymerization

    DOEpatents

    Boydston, Andrew J; Grubbs, Robert H; Daeffler, Chris; Momcilovic, Nebojsa

    2013-12-10

    Compositions and methods for adjustable lenses are provided. In some embodiments, the lenses contain a lens matrix material, a masking compound, and a prepolymer. The lens matrix material provides structure to the lens. The masking compound is capable of blocking polymerization or crosslinking of the prepolymer, until photoisomerization of the compound is triggered, and the compound is converted from a first isomer to a second isomer having a different absorption profile. The prepolymer is a composition that can undergo a polymerization or crosslinking reaction upon photoinitiation to alter one or more of the properties of the lenses.

  8. Composite Materials for Maxillofacial Prostheses.

    DTIC Science & Technology

    1980-08-01

    projected composite systems are elastomeric-shelled, liquid-filled * microcapsules . Experiments continued on the interfacial polymerization process with...filled microcapsules . Experiments continued on the interfacial polymerization process, with spherical, sealed, capsules achieved. Needs identified are...consists of liquid-filled, elastomeric-shelled microcapsules held together to form a deformable mass; this is to simulate the semi-liquid cellular structure

  9. Probing actin polymerization by intermolecular cross-linking.

    PubMed

    Millonig, R; Salvo, H; Aebi, U

    1988-03-01

    We have used N,N'-1,4-phenylenebismaleimide, a bifunctional sulfhydryl cross-linking reagent, to probe the oligomeric state of actin during the early stages of its polymerization into filaments. We document that one of the first steps in the polymerization of globular monomeric actin (G-actin) under a wide variety of ionic conditions is the dimerization of a significant fraction of the G-actin monomer pool. As polymerization proceeds, the yield of this initial dimer ("lower" dimer with an apparent molecular mass of 86 kD by SDS-PAGE [LD]) is attenuated, while an actin filament dimer ("upper" dimer with an apparent molecular mass of 115 kD by SDS-PAGE [UD] as characterized [Elzinga, M., and J. J. Phelan. 1984. Proc. Natl. Acad. Sci. USA. 81:6599-6602]) is formed. This shift from LD to UD occurs concomitant with formation of filaments as assayed by N-(1-pyrenyl)iodoacetamide fluorescence enhancement and electron microscopy. Isolated cross-linked LD does not form filaments, while isolated cross-linked UD will assemble into filaments indistinguishable from those polymerized from unmodified G-actin under typical filament-forming conditions. The presence of cross-linked LD does not effect the kinetics of polymerization of actin monomer, whereas cross-linked UD shortens the "lag phase" of the polymerization reaction in a concentration-dependent fashion. Several converging lines of evidence suggest that, although accounting for a significant oligomeric species formed during early polymerization, the LD is incompatible with the helical symmetry defining the mature actin filament; however, it could represent the interfilament dimer found in paracrystalline arrays or filament bundles. Furthermore, the LD is compatible with the unit cell structure and symmetry common to various types of crystalline actin arrays (Aebi, U., W. E. Fowler, G. Isenberg, T. D. Pollard, and P. R. Smith. 1981. J. Cell Biol. 91:340-351) and might represent the major structural state in which a mutant beta-actin (Leavitt, J., G. Bushar, T. Kakunaga, H. Hamada, T. Hirakawa, D. Goldman, and C. Merril. 1982. Cell. 28:259-268) is arrested under polymerizing conditions.

  10. Star-shaped PHB-PLA block copolymers: immortal polymerization with dinuclear indium catalysts.

    PubMed

    Yu, I; Ebrahimi, T; Hatzikiriakos, S G; Mehrkhodavandi, P

    2015-08-28

    The first example of a one-component precursor to star-shaped polyesters, and its utilization in the synthesis of previously unknown star-shaped poly(hydroxybutyrate)-poly(lactic acid) block copolymers, is reported. A series of such mono- and bis-benzyl alkoxy-bridged complexes were synthesized, fully characterized, and their solvent dependent solution structures and reactivity were examined. These complexes were highly active catalysts for the controlled polymerization of β-butyrolactone to form poly(hydroxybutyrate) at room temperature. Solution studies indicate that a mononuclear propagating species formed in THF and that the dimer-monomer equilibrium affects the rates of BBL polymerization. In the presence of linear and branched alcohols, these complexes catalyze well-controlled immortal polymerization and copolymerization of β-butyrolactone and lactide.

  11. Evaluation available encapsulation materials for low-cost long-life silicon photovoltaic arrays

    NASA Technical Reports Server (NTRS)

    Carmichael, D. C.; Gaines, G. B.; Noel, G. T.; Sliemers, F. A.; Nance, G. P.; Bunk, A. R.; Brockway, M. C.

    1978-01-01

    Experimental evaluation of selected encapsulation designs and materials based on an earlier study which have potential for use in low cost, long-life photovoltaic arrays are reported. The performance of candidate materials and encapsulated cells were evaluated principally for three types of encapsulation designs based on their potentially low materials and processing costs: (1) polymeric coatings, transparent conformal coatings over the cell with a structural-support substrate; (2) polymeric film lamination, cells laminated between two films or sheets of polymeric materials; and (3) glass-covered systems, cells adhesively bonded to a glass cover (superstrate) with a polymeric pottant and a glass or other substrate material. Several other design types, including those utilizing polymer sheet and pottant materials, were also included in the investigation.

  12. (1-Adamantyl)methyl glycidyl ether: a versatile building block for living polymerization.

    PubMed

    Moers, Christian; Wrazidlo, Robert; Natalello, Adrian; Netz, Isabelle; Mondeshki, Mihail; Frey, Holger

    2014-06-01

    (1-Adamantyl)methyl glycidyl ether (AdaGE) is introduced as a versatile monomer for oxyanionic polymerization, enabling controlled incorporation of adamantyl moieties in aliphatic polyethers. Via copolymerization with ethoxyethyl glycidyl ether (EEGE) and subsequent cleavage of the acetal protection groups of EEGE, hydrophilic linear polyglycerols with an adjustable amount of pendant adamantyl moieties are obtained. The adamantyl unit permits control over thermal properties and solubility profile of these polymers (LCST). Additionally, AdaGE is utilized as a termination agent in carbanionic polymerization, affording adamantyl-terminated polymers. Using these structures as macroinitiators for the polymerization of ethylene oxide affords amphiphilic, in-chain adamantyl-functionalized block copolymers. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Atomic moments in Mn 2CoAl thin films analyzed by X-ray magnetic circular dichroism

    DOE PAGES

    Jamer, M. E.; Assaf, B. A.; Sterbinsky, G. E.; ...

    2014-12-05

    Spin gapless semiconductors are known to be strongly affected by structural disorder when grown epitaxially as thin films. The magnetic properties of Mn 2CoAl thin films grown on GaAs (001) substrates are investigated here as a function of annealing. This study investigates the atomic-specific magnetic moments of Mn and Co atoms measured through X-ray magnetic circular dichroism as a function of annealing and the consequent structural ordering. Results indicate that the structural distortion mainly affects the Mn atoms as seen by the reduction of the magnetic moment from its predicted value.

  14. Liquid fuels from coal: analysis of a partial transition from oil to coal; light liquids in Zimbabwe's liquid fuels base

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Maya, R.S.

    1986-01-01

    This study assesses the feasibility of a coal based light liquids program as a way to localize forces that determine the flow of oil into the Zimbabwean economy. Methods in End-use Energy Analysis and Econometrics in which the utilization of petroleum energy is related to economic and industrial activity are used to gain insight into the structure and behavior of petroleum utilization in that country and to forecast future requirements of this resource. The feasibility of coal liquefaction as a substitute for imported oil is assessed by the use of engineering economics in which the technical economics of competing oilmore » supply technologies are analyzed and the best option is selected. Coal conversion technologies are numerous but all except the Fischer-Trosch indirect coal liquefaction technology are deficient in reliability as commercial ventures. The Fischer-Tropsch process by coincidence better matches Zimbabwe's product configuration than the less commercially advanced technologies. Using present value analysis to compare the coal liquefaction and the import option indicates that it is better to continue importing oil than to resort to a coal base for a portion of the oil supplies. An extended analysis taking special consideration of the risk and uncertainty factors characteristic of Zimbabwe's oil supply system indicates that the coal option is better than the import option. The relative infancy of the coal liquefaction industry and the possibility that activities responsible for the risk and uncertainty in the oil supply system will be removed in the future, however, make the adoption of the coal option an unusually risky undertaking.« less

  15. GIS Representation of Coal-Bearing Areas in North, Central, and South America

    USGS Publications Warehouse

    Tewalt, Susan J.; Kinney, Scott A.; Merrill, Matthew D.

    2008-01-01

    Worldwide coal consumption and international coal trade are projected to increase in the next several decades (Energy Information Administration, 2007). A search of existing literature indicates that in the Western Hemisphere, coal resources are known to occur in about 30 countries. The need exists to be able to depict these areas in a digital format for use in Geographic Information System (GIS) applications at small scales (large areas) and in visual presentations. Existing surficial geology GIS layers of the appropriate geologic age have been used as an approximation to depict the extent of coal-bearing areas in North, Central, and South America, as well as Greenland (fig. 1). Global surficial geology GIS data were created by the U.S. Geological Survey (USGS) for use in world petroleum assessments (Hearn and others, 2003). These USGS publications served as the major sources for the selection and creation of polygons to represent coal-bearing areas. Additional publications and maps by various countries and agencies were also used as sources of coal locations. GIS geologic polygons were truncated where literature or hardcopy maps did not indicate the presence of coal. The depicted areas are not adequate for use in coal resource calculations, as they were not adjusted for geologic structure and do not include coal at depth. Additionally, some coal areas in Central America could not be represented by the mapped surficial geology and are shown only as points based on descriptions or depictions from scientific publications or available maps. The provided GIS files are intended to serve as a backdrop for display of coal information. Three attributes of the coal that are represented by the polygons or points include geologic age (or range of ages), published rank (or range of ranks), and information source (published sources for age, rank, or physical location, or GIS geology base).

  16. Superacid Catalyzed Depolymerization and Conversion of Coals. Final Technical Report. [HF:BF{sub 2}/H{sub 2}

    DOE R&D Accomplishments Database

    Olah, G.

    1980-01-01

    We were interested in applying superacid catalyzed cleavage-depolymerization and ionic hydrogenation low temperature conversion of coal to liquid hydrocarbon, as well as obtaining information about the reactions involved and the structure of intermediates of the coal liquefaction process. In order to show the feasibility of our proposed research we have carried out preliminary investigation in these areas. Preceding our work there was no practical application of a superacid system to coal liquefaction. We carried out an extensive study of the potential of the HF:BF{sub 3}/H{sub 2} system for coal hydroliquefaction. Under varying conditions of reactant ratio, reaction time and temperature, we were able to obtain over 95% pyridine extractible product by treating coal in HF:BF{sub 3}:H{sub 2} system at approx. 100 degrees C for 4 hours. The coal to acid ratio was 1:5 and FB{sub 3} at 900 psi and H{sub 2} at 500 psi were used. These are extremely encouraging results in that the conditions used are drastically milder than those used in any known process, such as Exxon donor solvent and related processes. The cyclohexane extractibility of the treated coal was as high as 27% and the yield of liquid distillate at 400 degrees C/5 x 10{sup -3}/sup torr/ was approx. 30%. The infrared spectrum of product coal, extracts and distillates were distinctly different from the starting coal and show a significant increase in the amount of saturates. The {sup 1}H NMR spectrum of cyclohexane extract of the treated coal shows essentially all aliphatic photons. The spectra of other treated coal extracts show increased amounts and types of aliphatic protons as well as significant amounts of protons bound to unsaturated sites. This again indicates that the HF-BF{sub 3} system is depolymerizing the coal to small fragments which are soluble in non-polar solvents.

  17. Coal Formation and Geochemistry

    NASA Astrophysics Data System (ADS)

    Orem, W. H.; Finkelman, R. B.

    2003-12-01

    Coal is one of the most complex and challenging natural materials to analyze and to understand. Unlike most rocks, which consist predominantly of crystalline mineral grains, coal is largely an assemblage of amorphous, degraded plant remains metamorphosed to various degrees and intermixed with a generous sprinkling of minute syngenetic, diagenetic, epigenetic, and detrital mineral grains, and containing within its structure various amounts of water, oils, and gases. Each coal is unique, having been derived from different plant sources over geologic time, having experienty -45ced different thermal histories, and having been exposed to varying geologic processes. This diversity presents a challenge to constructing a coherent picture of coal geochemistry and the processes that influence the chemical composition of coal.Despite the challenge coal presents to geochemists, a thorough understanding of the chemistry and geology of this complex natural substance is essential because of its importance to our society. Coal is, and will remain for sometime, a crucial source of energy for the US and for many other countries (Figure 1). In the USA, more than half of the electricity is generated by coal-fired power plants, and almost 90% of the coal mined in the USA is sold for electricity generation (Pierce et al., 1996). It is also an important source of coke for steel production, chemicals, pharmaceuticals, and even perfumes ( Schobert, 1987). It may also, in some cases, be an economic source of various mineral commodities. The utilization of coal through mining, transport, storage, combustion, and the disposal of the combustion by-products, also presents a challenge to geochemists because of the wide range of environmental and human health problems arising from these activities. The sound and effective use of coal as a natural resource requires a better understanding of the geochemistry of coal, i.e., the chemical and mineralogical characteristics of the coal that control its technological behavior, by-product characteristics, and environmental and human health impacts. In this chapter, we will try to make geochemical sense of this wonderfully complex and important resource. (5K)Figure 1. Photograph of a low rank coal bed (lignite of Pliocene age) from southwestern Romania.

  18. Polymeric Thin Films for Organic Electronics: Properties and Adaptive Structures

    PubMed Central

    Cataldo, Sebastiano; Pignataro, Bruno

    2013-01-01

    This review deals with the correlation between morphology, structure and performance of organic electronic devices including thin film transistors and solar cells. In particular, we report on solution processed devices going into the role of the 3D supramolecular organization in determining their electronic properties. A selection of case studies from recent literature are reviewed, relying on solution methods for organic thin-film deposition which allow fine control of the supramolecular aggregation of polymers confined at surfaces in nanoscopic layers. A special focus is given to issues exploiting morphological structures stemming from the intrinsic polymeric dynamic adaptation under non-equilibrium conditions. PMID:28809362

  19. Did the Middlesboro, Kentucky, bolide impact event influence coal rank?

    USGS Publications Warehouse

    Hower, J.C.; Greb, S.F.; Kuehn, K.W.; Eble, C.F.

    2009-01-01

    The Middlesboro Basin, southeastern Kentucky, occurs on the Cumberland Overthrust Sheet and includes a ca. 5.5-km diameter impact structure. The Lower and Middle Pennsylvanian coal-bearing strata are faulted, with some evidence for shock metamorphism. The event post-dated the latest-Pennsylvanian-early-Permian thrusting and was likely prior to late-Mesozoic entrenchment of drainages. The impact of a 0.5-km meteor traveling at ca. 60,000??km/h would release about 1??EJ, the approximate equivalent of the instantaneous combustion of 30??Mt of coal. The coal rank, while increased slightly above the regional level, still is within the upper portion of the high volatile A bituminous rank range. This helps to constrain the depth of burial at the time of the impact. The coal would have had to have been at a depth of a few kilometers to have avoided a more substantial rank increase. In addition, it is possible that some of the coal rank increase might be attributable to movements along the cross-cutting Rocky Face fault, unrelated to the impact. ?? 2009 Elsevier B.V. All rights reserved.

  20. An analytical model of the mechanical properties of bulk coal under confined stress

    USGS Publications Warehouse

    Wang, G.X.; Wang, Z.T.; Rudolph, V.; Massarotto, P.; Finley, R.J.

    2007-01-01

    This paper presents the development of an analytical model which can be used to relate the structural parameters of coal to its mechanical properties such as elastic modulus and Poisson's ratio under a confined stress condition. This model is developed primarily to support process modeling of coalbed methane (CBM) or CO2-enhanced CBM (ECBM) recovery from coal seam. It applied an innovative approach by which stresses acting on and strains occurring in coal are successively combined in rectangular coordinates, leading to the aggregated mechanical constants. These mechanical properties represent important information for improving CBM/ECBM simulations and incorporating within these considerations of directional permeability. The model, consisting of constitutive equations which implement a mechanically consistent stress-strains correlation, can be used as a generalized tool to study the mechanical and fluid behaviors of coal composites. An example using the model to predict the stress-strain correlation of coal under triaxial confined stress by accounting for the elastic and brittle (non-elastic) deformations is discussed. The result shows a good agreement between the prediction and the experimental measurement. ?? 2007 Elsevier Ltd. All rights reserved.

  1. Sorption characteristic of coal as regards of gas mixtures emitted in the process of the self-heating of coal

    NASA Astrophysics Data System (ADS)

    Wojtacha-Rychter, Karolina; Smoliński, Adam

    2017-10-01

    One of the most challenging tasks in the coal mining sector is the detection of endogenous fire risks. Under field conditions, the distance between the points where samples for the analyses are collected and the actual place where coal self-heating takes place may be quite remote. Coal is a natural sorbent with a diverse character of pore structures which are surrounded by fractures and cleavage planes constituting ideal spaces for the flow and adsorption of gases. The gases (methane, ethane, ethylene, propane, propylene, acetylene, carbon dioxide, carbon monoxide, hydrogen) released from the source of fire migrate through the seam and may be subject to adsorption, or they may cause the desorption of gases accumulated in coal. Therefore, the values of reference sample concentrations may be overstated or understated, respectively. The objective of this experimental study was to investigate the adsorption phenomena accompanying the flow of a multi-component gas mixture through a coal bed which may occur in situ. The research was conducted by means of a method based on a series of calorimetric/chromatographic measurements taken to determine the amount of gases released during coal heating at various temperatures under laboratory conditions. Based on the results obtained in the course of the experiments, it was concluded that the amount of gas adsorbed in the seam depends on the type of coal and the gas. Within the multi-component gas mixture, hydrocarbons demonstrated the largest sorption capacity, especially as concerns propylene.

  2. Preparation and evaluation of coal-derived activated carbons for removal of mercury vapor from simulated coal combustion flue fases

    USGS Publications Warehouse

    Hsi, H.-C.; Chen, S.; Rostam-Abadi, M.; Rood, M.J.; Richardson, C.F.; Carey, T.R.; Chang, R.

    1998-01-01

    Coal-derived activated carbons (CDACs) were tested for their suitability in removing trace amounts of vapor-phase mercury from simulated flue gases generated by coal combustion. CDACs were prepared in bench-scale and pilot-scale fluidized-bed reactors with a three-step process, including coal preoxidation, carbonization, and then steam activation. CDACs from high-organicsulfur Illinois coals had a greater equilibrium Hg0 adsorption capacity than activated carbons prepared from a low-organic-sulfur Illinois coal. When a low-organic-sulfur CDAC was impregnated with elemental sulfur at 600 ??C, its equilibrium Hg0 adsorption capacity was comparable to the adsorption capacity of the activated carbon prepared from the high-organicsulfur coal. X-ray diffraction and sulfur K-edge X-ray absorption near-edge structure examinations showed that the sulfur in the CDACs was mainly in organic forms. These results suggested that a portion of the inherent organic sulfur in the starting coal, which remained in the CDACs, played an important role in adsorption of Hg0. Besides organic sulfur, the BET surface area and micropore area of the CDACs also influenced Hg0 adsorption capacity. The HgCl2 adsorption capacity was not as dependent on the surface area and concentration of sulfur in the CDACs as was adsorption of Hg0. The properties and mercury adsorption capacities of the CDACs were compared with those obtained for commercial Darco FGD carbon.

  3. Chemoselective, Stereospecific, and Living Polymerization of Polar Divinyl Monomers by Chiral Zirconocenium Catalysts.

    PubMed

    Vidal, Fernando; Gowda, Ravikumar R; Chen, Eugene Y-X

    2015-07-29

    This contribution reports the first chemoselective, stereospecific, and living polymerization of polar divinyl monomers, enabled by chiral ansa-zirconocenium catalysts through an enantiomorphic-site controlled coordination-addition polymerization mechanism. Silyl-bridged-ansa-zirconocenium ester enolate 2 has been synthesized and structurally characterized, but it exhibits low to negligible activity and stereospecificity in the polymerization of polar divinyl monomers including vinyl methacrylate (VMA), allyl methacrylate (AMA), 4-vinylbenzyl methacrylate (VBMA), and N,N-diallyl acrylamide (DAA). In contrast, ethylene-bridged-ansa-zirconocenium ester enolate 1 is highly active and stereospecific in the polymerization of such monomers including AMA, VBMA, and DAA. The polymerization by 1 is perfectly chemoselective for all four polar divinyl monomers, proceeding exclusively through conjugate addition across the methacrylic C═C bond, while leaving the pendant C═C bonds intact. The polymerization of DAA is most stereospecific and controlled, producing essentially stereoperfect isotactic PDAA with [mmmm] > 99%, M(n) matching the theoretical value (thus a quantitative initiation efficiency), and a narrow molecular weight distribution (Đ = 1.06-1.16). The stereospecificity is slightly lower for the AMA polymerization but still leading to highly isotactic poly(allyl methacrylate) (PAMA) with 95-97% [mm]. The polymerization of VBMA is further less stereospecific, affording PVBMA with 90-94% [mm], while the polymerization VMA is least stereospecific. Several lines of evidence from both homo- and block copolymerization results have demonstrated living characteristics of the AMA polymerization by 1. Mechanistic studies of this polymerization have yielded a monometallic coordination-addition polymerization mechanism involving the eight-membered chelating intermediate. Post-functionalization of isotactic polymers bearing the pendant vinyl group on every repeating unit via the thiol-ene "click" reaction achieves a full conversion of all the pendant double bonds to the corresponding thioether bonds. Photocuring of such isotactic polymers is also successful, producing an elastic material readily characterizable by dynamic mechanical analysis.

  4. XFAS SPECTROSCOPY ANALYSIS OF SELECTED HAP ELEMENTS IN FINE PM DERIVED FROM COAL COMBUSTION: JOURNAL ARTICLE

    EPA Science Inventory

    NRMRL-RTP-P-646 Shoji, T., Huggins, F.E., Huffman, G.P., Linak*, W.P., and Miller*, C.A. XFAS Spectroscopy Analysis of Selected HAP Elements in Fine PM Derived from Coal Combustion. Energy and Fuels 16 (2): (2002). 11/30/2001 X-ray absorption fine structure (XAFS) spectroscop...

  5. Assessment of corn and banana leaves as potential standardized substrates for leaf decomposition in streams affected by mountaintop removal coal mining, West Virginia, USA

    EPA Science Inventory

    Mountaintop removal and valley filling is a method of coal mining that buries Central Appalachian headwater streams. A 2007 federal court ruling highlighted the need for measurement of both ecosystem structure and function when assessing streams for mitigaton. Rapid functional as...

  6. Direct energy balance based active disturbance rejection control for coal-fired power plant.

    PubMed

    Sun, Li; Hua, Qingsong; Li, Donghai; Pan, Lei; Xue, Yali; Lee, Kwang Y

    2017-09-01

    The conventional direct energy balance (DEB) based PI control can fulfill the fundamental tracking requirements of the coal-fired power plant. However, it is challenging to deal with the cases when the coal quality variation is present. To this end, this paper introduces the active disturbance rejection control (ADRC) to the DEB structure, where the coal quality variation is deemed as a kind of unknown disturbance that can be estimated and mitigated promptly. Firstly, the nonlinearity of a recent power plant model is analyzed based on the gap metric, which provides guidance on how to set the pressure set-point in line with the power demand. Secondly, the approximate decoupling effect of the DEB structure is analyzed based on the relative gain analysis in frequency domain. Finally, the synthesis of the DEB based ADRC control system is carried out based on multi-objective optimization. The optimized ADRC results show that the integrated absolute error (IAE) indices of the tracking performances in both loops can be simultaneously improved, in comparison with the DEB based PI control and H ∞ control system. The regulation performance in the presence of the coal quality variation is significantly improved under the ADRC control scheme. Moreover, the robustness of the proposed strategy is shown comparable with the H ∞ control. Copyright © 2017. Published by Elsevier Ltd.

  7. Molecular Sensing by Nanoporous Crystalline Polymers

    PubMed Central

    Pilla, Pierluigi; Cusano, Andrea; Cutolo, Antonello; Giordano, Michele; Mensitieri, Giuseppe; Rizzo, Paola; Sanguigno, Luigi; Venditto, Vincenzo; Guerra, Gaetano

    2009-01-01

    Chemical sensors are generally based on the integration of suitable sensitive layers and transducing mechanisms. Although inorganic porous materials can be effective, there is significant interest in the use of polymeric materials because of their easy fabrication process, lower costs and mechanical flexibility. However, porous polymeric absorbents are generally amorphous and hence present poor molecular selectivity and undesired changes of mechanical properties as a consequence of large analyte uptake. In this contribution the structure, properties and some possible applications of sensing polymeric films based on nanoporous crystalline phases, which exhibit all identical nanopores, will be reviewed. The main advantages of crystalline nanoporous polymeric materials with respect to their amorphous counterparts are, besides a higher selectivity, the ability to maintain their physical state as well as geometry, even after large guest uptake (up to 10–15 wt%), and the possibility to control guest diffusivity by controlling the orientation of the host polymeric crystalline phase. The final section of the review also describes the ability of suitable polymeric films to act as chirality sensors, i.e., to sense and memorize the presence of non-racemic volatile organic compounds. PMID:22303150

  8. Azo polymeric micelles designed for colon-targeted dimethyl fumarate delivery for colon cancer therapy.

    PubMed

    Ma, Zhen-Gang; Ma, Rui; Xiao, Xiao-Lin; Zhang, Yong-Hui; Zhang, Xin-Zi; Hu, Nan; Gao, Jin-Lai; Zheng, Yu-Feng; Dong, De-Li; Sun, Zhi-Jie

    2016-10-15

    Colon-targeted drug delivery and circumventing drug resistance are extremely important for colon cancer chemotherapy. Our previous work found that dimethyl fumarate (DMF), the approved drug by the FDA for the treatment of multiple sclerosis, exhibited anti-tumor activity on colon cancer cells. Based on the pharmacological properties of DMF and azo bond in olsalazine chemical structure, we designed azo polymeric micelles for colon-targeted dimethyl fumarate delivery for colon cancer therapy. We synthesized the star-shape amphiphilic polymer with azo bond and fabricated the DMF-loaded azo polymeric micelles. The four-arm polymer star-PCL-azo-mPEG (sPCEG-azo) (constituted by star-shape PCL (polycaprolactone) and mPEG (methoxypolyethylene glycols)-olsalazine) showed self-assembly ability. The average diameter and polydispersity index of the DMF-loaded sPCEG-azo polymeric micelles were 153.6nm and 0.195, respectively. In vitro drug release study showed that the cumulative release of DMF from the DMF-loaded sPCEG-azo polymeric micelles was no more than 20% in rat gastric fluid within 10h, whereas in the rat colonic fluids, the cumulative release of DMF reached 60% in the initial 2h and 100% within 10h, indicating that the DMF-loaded sPCEG-azo polymeric micelles had excellent colon-targeted property. The DMF-loaded sPCEG-azo polymeric micelles had no significant cytotoxicity on colon cancer cells in phosphate buffered solution (PBS) and rat gastric fluid. In rat colonic fluid, the micelles showed significant cytotoxic effect on colon cancer cells. The blank sPCEG-azo polymeric micelles (without DMF) showed no cytotoxic effect on colon cancer cells in rat colonic fluids. In conclusion, the DMF-loaded sPCEG-azo polymeric micelles show colon-targeted DMF release and anti-tumor activity, providing a novel approach potential for colon cancer therapy. Colon-targeted drug delivery and circumventing drug resistance are extremely important for colon cancer chemotherapy. Our previous work found that dimethyl fumarate (DMF), the approved drug by the FDA for the treatment of multiple sclerosis, exhibited anti-tumor activities on colon cancer cells (Br J Pharmacol. 2015 172(15):3929-43.). Based on the pharmacological properties of DMF and azo bond in olsalazine chemical structure, we designed azo polymeric micelles for colon-targeted dimethyl fumarate delivery for colon cancer therapy. We found that the DMF-loaded sPCEG-azo polymeric micelles showed colon-targeted DMF release and anti-tumor activities, providing a novel approach potential for colon cancer therapy. Copyright © 2016 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  9. Multifaceted processes controlling the distribution of hazardous compounds in the spontaneous combustion of coal and the effect of these compounds on human health.

    PubMed

    Oliveira, Marcos L S; da Boit, Kátia; Pacheco, Fernanda; Teixeira, Elba C; Schneider, Ismael L; Crissien, Tito J; Pinto, Diana C; Oyaga, Rafael M; Silva, Luis F O

    2018-01-01

    Pollution generated by hazardous elements and persistent organic compounds that affect coal fire is a major environmental concern because of its toxic nature, persistence, and potential risk to human health. The coal mining activities are growing in the state of Santa Catarina in Brazil, thus the collateral impacts on the health and economy are yet to be analyzed. In addition, the environment is also enduring the collateral damage as the waste materials directly influence the coal by-products applied in civil constructions. This study was aimed to establish the relationships between the composition, morphology, and structural characteristics of ultrafine particles emitted by coal mine fires. In Brazil, the self-combustions produced by Al-Ca-Fe-Mg-Si coal spheres are rich in chalcophile elements (As, Cd, Cu, Hg, Pb, Sb, Se, Sn, and Zn), lithophile elements (Ce, Hf, In, La, Th, and U), and siderophile elements (Co, Cr, Mo, Fe, Ni, and V). The relationship between nanomineralogy and the production of hazardous elements as analyzed by advanced methods for the geochemical analysis of different materials were also delineated. The information obtained by the mineral substance analysis may provide a better idea for the understanding of coal-fire development and assessing the response of particular coal in different combustion processes. Copyright © 2017 Elsevier Inc. All rights reserved.

  10. Potential effects of surface coal mining on the hydrology of the Little Bear Creek area, Moorhead coal field, southeastern Montana

    USGS Publications Warehouse

    McClymonds, N.E.

    1986-01-01

    The Little Bear Creek area of the Moorhead Coal Field, 27 miles south of Ashland, Montana, contains large reserves of Federally owned coal that have been identified for potential lease sale. A hydrologic study was conducted in the area to describe existing hydrologic system and to assess potential effects of surface mining on local water resources. Hydrologic data collected from private wells, observation wells, test holes and springs indicate that the aquifers are coal and sandstone beds in the upper part of the Tongue River Member, Fort Union Formation (Paleocene age), and sand and gravel layers of valley alluvium (Pleistocene and Holocene age). Surface water is available from ephemeral flow along stretches of the main streams, and from stock ponds throughout the area. Mining the Anderson and Dietz coal beds would destroy one stock well and several stock ponds, would possibly interfere with the flow of one spring, and would lower the potentiometric surface within the coal and sandstone aquifers. The alluvial aquifer beneath Little Bear Creek and Davidson Draw would be removed at the mine site, as would sandstone and coal aquifers above the mine floor. Although mining would alter existing hydrologic systems, alternative water supplies are available. Planned structuring of the spoils and reconstruction of the alluvial aquifers could minimize downstream water-quality degradation. (USGS)

  11. Fabrication and Handling of 3D Scaffolds Based on Polymers and Decellularized Tissues.

    PubMed

    Shpichka, Anastasia; Koroleva, Anastasia; Kuznetsova, Daria; Dmitriev, Ruslan I; Timashev, Peter

    2017-01-01

    Polymeric, ceramic and hybrid material-based three-dimensional (3D) scaffold or matrix structures are important for successful tissue engineering. While the number of approaches utilizing the use of cell-based scaffold and matrix structures is constantly growing, it is essential to provide a framework of their typical preparation and evaluation for tissue engineering. This chapter describes the fabrication of 3D scaffolds using two-photon polymerization, decellularization and cell encapsulation methods and easy-to-use protocols allowing assessing the cell morphology, cytotoxicity and viability in these scaffolds.

  12. Soy-based polymeric surfactants prepared in carbon dioxide media and influence of structure on their surface properties

    USDA-ARS?s Scientific Manuscript database

    Soybean oil (SO) and epoxidized soybean oil (ESO) were polymerized in the CO2 media (supercritical and sub-supercritical) by BF3•OEt2 catalyst. The resulting polymers (PSO and PESO) were hydrolyzed into polysoaps (HPSO) and (HPESO) with Na+, K+, or TEA+ (triethanolamine, ammonium salt) counter ions....

  13. Conductive Polymer Synthesis with Single-Crystallinity via a Novel Plasma Polymerization Technique for Gas Sensor Applications.

    PubMed

    Park, Choon-Sang; Kim, Dong Ha; Shin, Bhum Jae; Kim, Do Yeob; Lee, Hyung-Kun; Tae, Heung-Sik

    2016-09-30

    This study proposes a new nanostructured conductive polymer synthesis method that can grow the single-crystalline high-density plasma-polymerized nanoparticle structures by enhancing the sufficient nucleation and fragmentation of the pyrrole monomer using a novel atmospheric pressure plasma jet (APPJ) technique. Transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), and field emission scanning electron microscopy (FE-SEM) results show that the plasma-polymerized pyrrole (pPPy) nanoparticles have a fast deposition rate of 0.93 µm·min -1 under a room-temperature process and have single-crystalline characteristics with porous properties. In addition, the single-crystalline high-density pPPy nanoparticle structures were successfully synthesized on the glass, plastic, and interdigitated gas sensor electrode substrates using a novel plasma polymerization technique at room temperature. To check the suitability of the active layer for the fabrication of electrochemical toxic gas sensors, the resistance variations of the pPPy nanoparticles grown on the interdigitated gas sensor electrodes were examined by doping with iodine. As a result, the proposed APPJ device could obtain the high-density and ultra-fast single-crystalline pPPy thin films for various gas sensor applications. This work will contribute to the design of highly sensitive gas sensors adopting the novel plasma-polymerized conductive polymer as new active layer.

  14. The Morphology of Emulsion Polymerized Latex Particles

    DOE R&D Accomplishments Database

    Wignall, G. D.; Ramakrishnan, V. R.; Linne, M. A.; Klein, A.; Sperling, L. H.; Wai, M. P.; Gelman, R. A.; Fatica, M. G.; Hoerl, R. H.; Fisher, L. W.

    1987-11-01

    Under monomer starved feed conditions, emulsion polymerization of perdeuterated methyl methacrylate and styrene in the presence of preformed polymethylmethacrylate latexes resulted in particles with a core-shell morphology, as determined by small-angle neutron scattering (SANS) analysis for a hollow sphere. The locus of polymerization of the added deuterated monomer is therefore at the particle surface. In similar measurements a statistical copolymer of styrene and methyl methacrylate was used as seed particles for further polymerization of trideuteromethyl methacrylate. The resulting polymer latex was again shown to have a core-shell morphological structure as determined by SANS. SANS experiments were also undertaken on polystyrene latexes polymerized by equilibrium swelling methods, with deuterated polymer forming the first or second step. The experiments covered a molecular weight range of 6 x 10{sup 4} 10{sup 6} the molecular weights are consistent with the experimental errors, indicating that the deuterium labeled molecules are randomly distributed in the latex. These results led to the finding that the polymer chains were constrained in the latex particles by factors of 2 to 4 from the relaxed coil dimensions. For M < 10{sup 6} g/mol SANS gave zero angle scattering intensities much higher than expected on the basis of a random distribution of labeled molecules. Several models were examined, including the possible development of core-shell structures at lower molecular weights.

  15. Thermal tuning the reversible optical band gap of self-assembled polystyrene photonic crystals

    NASA Astrophysics Data System (ADS)

    Vakili Tahami, S. H.; Pourmahdian, S.; Shirkavand Hadavand, B.; Azizi, Z. S.; Tehranchi, M. M.

    2016-11-01

    Nano-sized polymeric colloidal particles could undergo self-organization into three-dimensional structures to produce desired optical properties. In this research, a facile emulsifier-free emulsion polymerization method was employed to synthesize highly mono-disperse sub-micron polystyrene colloids. A high quality photonic crystal (PhC) structure was prepared by colloidal polystyrene. The reversible thermal tuning effect on photonic band gap position as well as the attenuation of the band gap was investigated in detail. The position of PBG can be tuned from 420 nm to 400 nm by varying the temperature of the PhC structure, reversibly. This reversible effect provides a reconfigurable PhC structure which could be used as thermo-responsive shape memory polymers.

  16. Single-anchor support and supercritical CO2 drying enable high-precision microfabrication of three-dimensional structures.

    PubMed

    Maruo, Shoji; Hasegawa, Takuya; Yoshimura, Naoki

    2009-11-09

    In high-precision two-photon microfabrication of three-dimensional (3-D) polymeric microstructures, supercritical CO(2) drying was employed to reduce surface tension, which tends to cause the collapse of micro/nano structures. Use of supercritical drying allowed high-aspect ratio microstructures, such as micropillars and cantilevers, to be fabricated. We also propose a single-anchor supporting method to eliminate non-uniform shrinkage of polymeric structures otherwise caused by attachment to the substrate. Use of this method permitted frame models such as lattices to be produced without harmful distortion. The combination of supercritical CO(2) drying and the single-anchor supporting method offers reliable high-precision microfabrication of sophisticated, fragile 3-D micro/nano structures.

  17. Geologic coal assessment: The interface with economics

    USGS Publications Warehouse

    Attanasi, E.D.

    2001-01-01

    Geologic resource assessments describe the location, general characteristics, and estimated volumes of resources, whether in situ or technically recoverable. Such compilations are only an initial step in economic resource evaluation. This paper identifies, by examples from the Illinois and Appalachian basins, the salient features of a geologic assessment that assure its usefulness to downstream economic analysis. Assessments should be in sufficient detail to allocate resources to production units (mines or wells). Coal assessments should include the spatial distribution of coal bed characteristics and the ability to allocate parts of the resource to specific mining technologies. For coal bed gas assessment, the production well recoveries and well deliverability characteristics must be preserved and the risk structure should be specified so dryholes and noncommercial well costs are recovered by commercially successful wells. ?? 2001 International Association for Mathematical Geology.

  18. The investigation of chemical structure of coal macerals via transmitted-light FT-IR microscopy by X. Sun

    USGS Publications Warehouse

    Hower, J.C.; Suarez-Ruiz, I.; Mastalerz, Maria; Cook, A.C.

    2007-01-01

    A recent paper by Sun [X. Sun, Spectrochim. Acta A 62 (1-3) (2005) 557] attempts to characterize a variety of liptinite, termed "barkinite", from Chinese Permian coals. The component identified does not appear to fundamentally differ from previously-described liptinite macerals included in the International Committee for Coal and Organic Petrology's system of maceral nomenclature. Further, chemical comparisons made with macerals from coals of different rank and age are flawed because the author did not account for changes in chemistry with rank or for the chemical changes associated with botanical changes through geologic time. The author has not satisfactorily proved his hypothesis that the component differs morphologically or chemically from known liptinite-group macerals. ?? 2006 Elsevier B.V. All rights reserved.

  19. AFM Imaging Reveals Topographic Diversity of Wild Type and Z Variant Polymers of Human α1-Proteinase Inhibitor

    DOE PAGES

    Gaczynska, Maria; Karpowicz, Przemyslaw; Stuart, Christine E.; ...

    2016-03-23

    α 1-Proteinase inhibitor (antitrypsin) is a canonical example of the serpin family member that binds and inhibits serine proteases. The natural metastability of serpins is crucial to carry out structural rearrangements necessary for biological activity. However, the enhanced metastability of the mutant Z variant of antitrypsin, in addition to folding defect, may substantially contribute to its polymerization, a process leading to incurable serpinopathy. The metastability also impedes structural studies on the polymers. There are no crystal structures of Z monomer or any kind of polymers larger than engineered wild type (WT) trimer. Our understanding of polymerization mechanisms is based onmore » biochemical data using in vitro generated WT oligomers and molecular simulations. Here we applied atomic force microscopy (AFM) to compare topography of monomers, in vitro formed WT oligomers, and Z type polymers isolated from transgenic mouse liver. We found the AFM images of monomers closely resembled an antitrypsin outer shell modeled after the crystal structure. We confirmed that the Z variant demonstrated higher spontaneous propensity to dimerize than WT monomers. We also detected an unexpectedly broad range of different types of polymers with periodicity and topography depending on the applied method of polymerization. Short linear oligomers of unit arrangement similar to the Z polymers were especially abundant in heat-treated WT preparations. Long linear polymers were a prominent and unique component of liver extracts. However, the liver preparations contained also multiple types of oligomers of topographies undistinguishable from those found inWT samples polymerized with heat, low pH or guanidine hydrochloride treatments. In conclusion, we established that AFM is an excellent technique to assess morphological diversity of antitrypsin polymers, which is important for etiology of serpinopathies. These data also support previous, but controversial models of in vivo polymerization showing a surprising diversity of polymer topography. PLOS« less

  20. Polymeric Sulfated Amino Acid Surfactants: A New Class of Versatile Chiral Selectors for Micellar Electrokinetic Chromatography (MEKC) and MEKC-MS

    PubMed Central

    Ali Rizvi, Syed Asad; Zheng, Jie; Apkarian, Robert P.; Dublin, Steven N.; Shamsi, Shahab A.

    2008-01-01

    In this work, three amino acids derived (L-leucinol, L-isoleucinol and L-valinol) sulfated chiral surfactants are synthesized and polymerized. These chiral sulfated surfactants are thoroughly characterized to determine critical micelle concentration, aggregation number, polarity, optical rotation and partial specific volume. For the first time the morphological behavior of polymeric sulfated surfactants is revealed using cryogenic high-resolution electron microscopy (cryo-HRSEM). The polysodium N-undecenoyl-L-leucine sulfate (poly-L-SUCLS) shows distinct tubular structure, while polysodium N-undecenoyl-L-valine sulfate (poly-L-SUCVS) also shows tubular morphology but without any distinct order of the tubes. On the other hand, polysodium N-undecenoyl-L-isoleucine sulfate (poly-L-SUCILS) displays random distribution of coiled/curved filaments with heavy association of tightly and loosely bound water. All three polymeric sulfated surfactants are compared for enantio-separation of broad range of structurally diverse racemic compounds at very acidic, neutral and basic pH conditions in micellar electrokinetic chromatography (MEKC). A small combinatorial library of 10 structurally related phenylethylamines (PEAs) is investigated for chiral separation under acidic and moderately acidic to neutral pH conditions using an experimental design. In contrast to neutral pH conditions, at acidic pH, significantly enhanced chiral resolution is obtained for class I and class II PEAs due to the compact structure of polymeric sulfated surfactants. It is observed that the presence of hydroxy group on the benzene ring of PEAs resulted in deterioration of enantioseparation. A sensitive MEKC-mass spectrometry (MS) method is developed for one of the PEA (e.g., (±)-pseudoephedrine) in human urine. Very low limit of detection (LOD) is obtained at pH 2.0 (LOD 325 ng/mL), which is ca 16 times better compared to pH 8.0 (LOD 5.2 µg/mL). Other broad range of chiral analytes (β-blockers, phenoxypropionic acid, benzoin derivatives, PTH-amino acids, and benzodiazepinones) studied also provided improved chiral separation at low pH compared to high pH conditions. Among the three polymeric sulfated surfactants, poly-L-SUCILS with two chiral centers on the polymer head group provided overall higher enantioresolution for the investigated acidic, basic and neutral compounds. This work clearly demonstrates for the first time the superiority of chiral separation and sensitive MS detection at low pH over conventional high pH chiral separation and detection employing anionic chiral polymeric surfactants in MEKC and MEKC-MS. PMID:17263313

  1. Environmental risks associated with unconventional gas extraction: an Australian perspective

    NASA Astrophysics Data System (ADS)

    Mallants, Dirk; Bekele, Elise; Schmidt, Wolfgang; Miotlinski, Konrad; Gerke Gerke, Kirill

    2015-04-01

    Coal seam gas is naturally occurring methane gas (CH4) formed by the degradation of organic material in coal seam layers over geological times, typically over several millions of years. Unlike conventional gas resources, which occur as discrete accumulations in traps formed by folds and other structures in sedimentary layers, coal seam gas is generally trapped in low permeable rock by adsorption of the gas molecules within the rock formation and cannot migrate to a trap and form a conventional gas deposit. Extraction of coal seam gas requires producers to de pressurise the coal measures by abstracting large amounts of groundwater through pumping. For coal measures that have too low permeabilities for gas extraction to be economical, mechanical and chemical techniques are required to increase permeability and thus gas yield. One such technique is hydraulic fracturing (HF). Hydraulic fracturing increases the rate and total amount of gas extracted from coal seam gas reservoirs. The process of hydraulic fracturing involves injecting large volumes of hydraulic fracturing fluids under high pressure into the coal seam layers to open up (i.e. fracture) the gas-containing coal layers, thus facilitating extraction of methane gas through pumping. After a hydraulic fracturing operation has been completed in a coal seam gas well, the fracturing fluid pressure is lowered and a significant proportion of the injected fluid returns to the surface as "flowback" water via coal seam gas wells. Flowback water is fluid that returns to the surface after hydraulic fracturing has occurred but before the well is put into production; whereas produced water is fluid from the coal measure that is pumped to the surface after the well is in production. This paper summarises available literature data from Australian coal seam gas practices on i) spills from hydraulic fracturing-related fluids used during coal seam gas drilling and hydraulic fracturing operations, ii) leaks to soil and shallow groundwater of flowback water and produced water from surface impoundments, iii) risks from well integrity failure, and iv) increased gas in water bores.

  2. Create a Consortium and Develop Premium Carbon Products from Coal

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Frank Rusinko; John Andresen; Jennifer E. Hill

    2006-01-01

    The objective of these projects was to investigate alternative technologies for non-fuel uses of coal. Special emphasis was placed on developing premium carbon products from coal-derived feedstocks. A total of 14 projects, which are the 2003 Research Projects, are reported herein. These projects were categorized into three overall objectives. They are: (1) To explore new applications for the use of anthracite in order to improve its marketability; (2) To effectively minimize environmental damage caused by mercury emissions, CO{sub 2} emissions, and coal impounds; and (3) To continue to increase our understanding of coal properties and establish coal usage in non-fuelmore » industries. Research was completed in laboratories throughout the United States. Most research was performed on a bench-scale level with the intent of scaling up if preliminary tests proved successful. These projects resulted in many potential applications for coal-derived feedstocks. These include: (1) Use of anthracite as a sorbent to capture CO{sub 2} emissions; (2) Use of anthracite-based carbon as a catalyst; (3) Use of processed anthracite in carbon electrodes and carbon black; (4) Use of raw coal refuse for producing activated carbon; (5) Reusable PACs to recycle captured mercury; (6) Use of combustion and gasification chars to capture mercury from coal-fired power plants; (7) Development of a synthetic coal tar enamel; (8) Use of alternative binder pitches in aluminum anodes; (9) Use of Solvent Extracted Carbon Ore (SECO) to fuel a carbon fuel cell; (10) Production of a low cost coal-derived turbostratic carbon powder for structural applications; (11) Production of high-value carbon fibers and foams via the co-processing of a low-cost coal extract pitch with well-dispersed carbon nanotubes; (12) Use of carbon from fly ash as metallurgical carbon; (13) Production of bulk carbon fiber for concrete reinforcement; and (14) Characterizing coal solvent extraction processes. Although some of the projects funded did not meet their original goals, the overall objectives of the CPCPC were completed as many new applications for coal-derived feedstocks have been researched. Future research in many of these areas is necessary before implementation into industry.« less

  3. Fibrinogen variant B[beta]D432A has normal polymerization but does not bind knob 'B'

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bowley, Sheryl R.; Lord, Susan T.; UNC)

    2009-10-23

    Fibrinogen residue B{beta}432Asp is part of hole 'b' that interacts with knob 'B,' whose sequence starts with Gly-His-Arg-Pro-amide (GHRP). Because previous studies showed B{beta}D432A has normal polymerization, we hypothesized that B{beta}432Asp is not critical for knob 'B' binding and that new knob-hole interactions would compensate for the loss of this Asp residue. To test this hypothesis, we solved the crystal structure of fragment D from B{beta}D432A. Surprisingly, the structure (rfD-B{beta}D432A+GH) showed the peptide GHRP was not bound to hole 'b.' We then re-evaluated the polymerization of this variant by examining clot turbidity, clot structure, and the rate of FXIIIa cross-linking.more » The turbidity and the rate of - dimer formation for B{beta}D432A were indistinguishable compared with normal fibrinogen. Scanning electron microscopy showed no significant differences between the clots of B{beta}D432A and normal, but the thrombin-derived clots had thicker fibers than clots obtained from batroxobin, suggesting that cleavage of FpB is more important than 'B:b' interactions. We conclude that hole 'b' and 'B:b' knob-hole binding per se have no influence on fibrin polymerization.« less

  4. Ion Transport and Structural Properties of Polymeric Electrolytes and Ionic Liquids from Molecular Dynamics Simulations

    NASA Astrophysics Data System (ADS)

    Borodin, Oleg

    2010-03-01

    Molecular dynamics simulations are well suited for exploring electrolyte structure and ion transport mechanisms on the nanometer length scale and the nanosecond time scales. In this presentation we will describe how MD simulations assist in answering fundamental questions about the lithium transport mechanisms in polymeric electrolytes and ionic liquids. In particular, in the first part of the presentation the extent of ion aggregation, the structure of ion aggregates and the lithium cation diffusion in binary polymeric electrolytes will be compared with that of single-ion conducting polymers. In the second part of the talk, the lithium transport in polymeric electrolytes will be compared with that of three ionic liquids ( [emim][FSI] doped with LiFSI , [pyr13][FSI] doped with LiFSI, [emim][BF4] doped with LiBF4). The relation between ionic liquid self-diffusion, conductivity and thermodynamic properties will be discussed in details. A number of correlations between heat of vaporization Hvap, cation-anion binding energy (E+/-), molar volume (Vm), self-diffusion coefficient (D) and ionic conductivity for 29 ionic liquids have been investigated using MD simulations. A significant correlation between D and Hvap has been found, while best correlation was found for -log((D Vm)) vs. Hvap+0.28E+/-. A combination of enthalpy of vaporization and a fraction of the cation-anion binding energy was suggested as a measure of the effective cohesive energy for ionic liquids.

  5. The sorption properties of polymers with molecular imprints of 2,4-dichlorophenoxyacetic acid synthesized by various methods

    NASA Astrophysics Data System (ADS)

    Dmitrienko, S. G.; Popov, S. A.; Chumichkina, Yu. A.; Zolotov, Yu. A.

    2011-03-01

    New sorbents, polymers with molecular imprints of 2,4-dichlorophenoxyacetic acid (2,4-D), were prepared on the basis of acrylamide. The sorbents were synthesized by thermal polymerization methods with and without the use of ultrasound, photopolymerization, and suspension polymerization. The specific surface area of the products was estimated and their sorption properties were studied. Polymers with molecular imprints prepared by thermal polymerization with the use of ultrasound and by suspension polymerization showed the best ability to repeatedly bind 2,4-D. The selectivity of polymers was estimated for the example of structurally related compounds. It was shown that the method of synthesis decisively influenced not only the ability of sorbents to repeatedly bind 2,4-D but also their selectivity.

  6. Curing dynamics of photopolymers measured by single-shot heterodyne transient grating method.

    PubMed

    Arai, Mika; Fujii, Tomomi; Inoue, Hayato; Kuwahara, Shota; Katayama, Kenji

    2013-01-01

    The heterodyne transient grating (HD-TG) method was first applied to the curing dynamics measurement of photopolymers. The curing dynamics for various monomers including an initiator (2.5 vol%) was monitored optically via the refractive index change after a single UV pulse irradiation. We could obtain the polymerization time and the final change in the refractive index, and the parameters were correlated with the viscosity, molecular structure, and reaction sites. As the polymerization time was longer, the final refractive change was larger, and the polymerization time was explained in terms of the monomer properties.

  7. Absence of first-order unbinding transitions of fluid and polymerized membranes

    NASA Technical Reports Server (NTRS)

    Grotehans, Stefan; Lipowsky, Reinhard

    1990-01-01

    Unbinding transitions of fluid and polymerized membranes are studied by renormalization-group (RG) methods. Two different RG schemes are used and found to give rather consistent results. The fixed-point structure of both RG's exhibits a complex behavior as a function of the decay exponent tau for the fluctuation-induced interaction of the membranes. For tau greater than tau(S2) interacting membranes can undergo first-order transitions even in the strong-fluctuation regime. These estimates for tau(S2) imply, however, that both fluid and polymerized membranes unbind in a continuous way in the absence of lateral tension.

  8. Synthesis and activity of novel analogs of hemiasterlin as inhibitors of tubulin polymerization: modification of the A segment.

    PubMed

    Yamashita, Ayako; Norton, Emily B; Kaplan, Joshua A; Niu, Chuan; Loganzo, Frank; Hernandez, Richard; Beyer, Carl F; Annable, Tami; Musto, Sylvia; Discafani, Carolyn; Zask, Arie; Ayral-Kaloustian, Semiramis

    2004-11-01

    Analogs of hemiasterlin (1) and HTI-286 (2), which contain various aromatic rings in the A segment, were synthesized as potential inhibitors of tubulin polymerization. The structure-activity relationships related to stereo- and regio-chemical effects of substituents on the aromatic ring in the A segment were studied. Analogs, which carry a meta-substituted phenyl ring in the A segment show comparable activity for inhibition of tubulin polymerization to 2, as well as in the cell proliferation assay using KB cells containing P-glycoprotein, compared to those of 1 and 2.

  9. Cationic antimicrobial polymers and their assemblies.

    PubMed

    Carmona-Ribeiro, Ana Maria; de Melo Carrasco, Letícia Dias

    2013-05-10

    Cationic compounds are promising candidates for development of antimicrobial agents. Positive charges attached to surfaces, particles, polymers, peptides or bilayers have been used as antimicrobial agents by themselves or in sophisticated formulations. The main positively charged moieties in these natural or synthetic structures are quaternary ammonium groups, resulting in quaternary ammonium compounds (QACs). The advantage of amphiphilic cationic polymers when compared to small amphiphilic molecules is their enhanced microbicidal activity. Besides, many of these polymeric structures also show low toxicity to human cells; a major requirement for biomedical applications. Determination of the specific elements in polymers, which affect their antimicrobial activity, has been previously difficult due to broad molecular weight distributions and random sequences characteristic of radical polymerization. With the advances in polymerization control, selection of well defined polymers and structures are allowing greater insight into their structure-antimicrobial activity relationship. On the other hand, antimicrobial polymers grafted or self-assembled to inert or non inert vehicles can yield hybrid antimicrobial nanostructures or films, which can act as antimicrobials by themselves or deliver bioactive molecules for a variety of applications, such as wound dressing, photodynamic antimicrobial therapy, food packing and preservation and antifouling applications.

  10. Cationic Antimicrobial Polymers and Their Assemblies

    PubMed Central

    Carmona-Ribeiro, Ana Maria; de Melo Carrasco, Letícia Dias

    2013-01-01

    Cationic compounds are promising candidates for development of antimicrobial agents. Positive charges attached to surfaces, particles, polymers, peptides or bilayers have been used as antimicrobial agents by themselves or in sophisticated formulations. The main positively charged moieties in these natural or synthetic structures are quaternary ammonium groups, resulting in quaternary ammonium compounds (QACs). The advantage of amphiphilic cationic polymers when compared to small amphiphilic molecules is their enhanced microbicidal activity. Besides, many of these polymeric structures also show low toxicity to human cells; a major requirement for biomedical applications. Determination of the specific elements in polymers, which affect their antimicrobial activity, has been previously difficult due to broad molecular weight distributions and random sequences characteristic of radical polymerization. With the advances in polymerization control, selection of well defined polymers and structures are allowing greater insight into their structure-antimicrobial activity relationship. On the other hand, antimicrobial polymers grafted or self-assembled to inert or non inert vehicles can yield hybrid antimicrobial nanostructures or films, which can act as antimicrobials by themselves or deliver bioactive molecules for a variety of applications, such as wound dressing, photodynamic antimicrobial therapy, food packing and preservation and antifouling applications. PMID:23665898

  11. Design, synthesis, and characterization of new phosphazene related materials, and study the structure property correlations

    NASA Astrophysics Data System (ADS)

    Tian, Zhicheng

    The work described in this thesis is divided into three major parts, and all of which involve the exploration of the chemistry of polyphosphazenes. The first part (chapters 2 and 3) of my research is synthesis and study polyphoshazenes for biomedical applications, including polymer drug conjugates and injectable hydrogels for drug or biomolecule delivery. The second part (chapters 4 and 5) focuses on the synthesis of several organic/inorganic hybrid polymeric structures, such as diblock, star, brush and palm tree copolymers using living cationic polymerization and atom transfer radical polymerization techniques. The last part (chapters 6 and 7) is about exploratory synthesis of new polymeric structures with fluorinated side groups or cycloaliphatic side groups, and the study of new structure property relationships. Chapter 1 is an outline of the fundamental concepts for polymeric materials, as such the history, important definitions, and some introductory material for to polymer chemistry and physics. The chemistry and applications of phopshazenes is also briefly described. Chapter 2 is a description of the design, synthesis, and characterization of development of a new class of polymer drug conjugate materials based on biodegradable polyphosphazenes and antibiotics. Poly(dichlorophosphazene), synthesized by a thermal ring opening polymerization, was reacted with up to 25 mol% of ciprofloxacin or norfloxacin and three different amino acid esters (glycine, alanine, or phenylalanine) as cosubstituents via macromolecular substitutions. Nano/microfibers of several selected polymers were prepared by an electrospinning technique. Chapter 3 is concerned with the development of a class of injectable and biodegradable hydrogels based on water-soluble poly(organophosphazenes) containing oligo(ethylene glycol) methyl ethers and glycine ethyl esters. The hydrogels can be obtained by mixing alpha-cyclodextrin aqueous solution and poly(organophosphazenes) aqueous solution in various gelation rates depending on the polymer structures and the concentrations. The rheological measurements of the supramolecular hydrogels indicate a fast gelation process and flowable character under a large stain. Chapter 4 outlines the preparation of a number of amphiphilic diblock copolymers based on poly[bis(trifluoroethoxy)phosphazene] (TFE) as the hydrophobic block and poly(dimethylaminoethylmethacrylate) (PDMAEMA) as the hydrophilic block. The TFE block was synthesized first by the controlled living cationic polymerization of a phosphoranimine, followed by replacement of all the chlorine atoms using sodium trifluoroethoxide. To allow for the growth of the PDMAEMA block, 3-azidopropyl-2-bromo-2-methylpropanoate, an atom transfer radical polymerization (ATRP) initiator, was grafted onto the endcap of the TFE block via the 'click' reaction followed by the ATRP of 2-(dimethylamino)ethyl methacrylate (DMAEMA). Chapter 5 is a report on the design and assembly of polyphosphazene materials based on the non-covalent "host--guest" interactions either at the terminus of the polymeric main-chains or the pendant side-chains. The supramolecular interaction at the main chain terminus was used to produce amphiphilic palm-tree like pseudo-block copolymers via host-guest interactions between an adamantane end-functionalized polyphosphazene and a 4-armed beta-cyclodextrin (beta-CD) initiated poly[poly(ethylene glycol) methyl ether methacylate] branched-star type polymer. The formation of micelles of the obtained amphiphiles was analyzed by fluorescence technique, dynamic light scattering, transmission electron microscopy, and atomic force microscopy. Chapter 6 is an investigation of the influence of bulky fluoroalkoxy side groups on the properties of polyphosphazenes. A new series of mixed-substituent high polymeric poly(fluoroalkoxyphosphazenes) containing trifluoroethoxy and branched fluoroalkoxy side groups was synthesized and characterized by NMR and GPC methods. These polymers contained 19--29 mol% of di-branched hexafluoropropoxy groups or 4mol% of tri-branched tert-perfluorobutoxy groups, which serve as regio-irregularities to reduce the macromolecular microcrystallinity. The structure--property correlations of the polymers were then analyzed and interpreted by several techniques: specifically by the thermal behavior by DSC and TGA methods, the crystallinity by wide-angle X-ray diffraction, and the surface hydrophobicity/oleophobicity by contact angle measurements. (Abstract shortened by UMI.). Chapter 7 is an outline of the exploratory synthesis of a new series of phosphazene model cyclic trimers and single- and mixed- substituent high polymers containing cyclic aliphatic rings, --CnH2n-1 (where n = 4--8). The cylco-aliphatic side group containing phosphazenes expand the structural and property boundaries of phosphazene chemistry, and suggest additional approaches for studying slow macromolecular substitution reactions and substituent exchange reactions.

  12. Analysis of factors determining enterprise value of company merger and acquisition: A case study of coal in Kalimantan, Indonesia

    NASA Astrophysics Data System (ADS)

    Candra, Ade; Pasasa, Linus A.; Simatupang, Parhimpunan

    2015-09-01

    The main purpose of this paper is looking at the relationship between the factors of technical, financial and legal with enterprise value in mergers and acquisitions of coal companies in Kalimantan, Indonesia over the last 10 years. Data obtained from secondary data sources in the company works and from published data on the internet. The data thus obtained are as many as 46 secondary data with parameters resources, reserves, stripping ratio, calorific value, distance from pit to port, and distance from ports to vessels, production per annum, the cost from pit to port, from port to vessel costs, royalties, coal price and permit status. The data was analysis using structural equation modeling (SEM) to determine the factors that most significant influence enterprise value of coal company in Kalimantan. The result shows that a technical matter is the factor that most affects the value of enterprise in coal merger and acquisition company. Financial aspect is the second factor that affects the enterprise value.

  13. Assessment of Appalachian basin oil and gas resources: Carboniferous Coal-bed Gas Total Petroleum System: Chapter G.1 in Coal and petroleum resources in the Appalachian basin: distribution, geologic framework, and geochemical character

    USGS Publications Warehouse

    Milici, Robert C.; Ruppert, Leslie F.; Ryder, Robert T.

    2014-01-01

    Trap formation began with the deposition of the peat deposits during the Mississippian and continued into the Late Pennsylvanian and Permian, when strata of the Appalachian Plateaus were deformed during the Alleghanian orogeny. The seals are the connate waters that occupy fractures and larger pore spaces within the coal beds, as well as the fine-grained, siliciclastic sedimentary strata that are intercalated with the coal. The critical moment for the petroleum system occurred during the Alleghanian orogeny, when deformation resulted in the geologic structures in the eastern part of the Appalachian basin that enhanced fracture porosity within the coal beds. In places, burial by thrust sheets (thrust loading) in the Valley and Ridge physiographic province may have resulted in the additional generation of thermogenic coalbed methane in the Pennsylvania Anthracite region and in the semianthracite deposits of Virginia and West Virginia, although other explanations have been offered.

  14. Synthesis of imine bond containing insoluble polymeric ligand and its transition metal complexes, structural characterization and catalytic activity on esterification reaction.

    PubMed

    Gönül, İlyas; Ay, Burak; Karaca, Serkan; Saribiyik, Oguz Yunus; Yildiz, Emel; Serin, Selahattin

    2017-01-01

    In this study, synthesis of insoluble polymeric ligand (L) and its transition metal complexes [Cu(L)Cl 2 ]·2H 2 O (1) , [Co(L)Cl 2 (H 2 O) 2 ] (2) and [Ni(L)Cl 2 (H 2 O) 2 ] (3) , having the azomethine groups, were synthesized by the condensation reactions of the diamines and dialdehydes. The structural properties were characterized by the analytical and spectroscopic methods using by elemental analysis, Fourier Transform Infrared, Thermo Gravimetric Analysis, Powder X-ray Diffraction, magnetic susceptibility and Inductively Coupled Plasma. The solubilities of the synthesized polymeric materials were also investigated and found as insoluble some organic and inorganic solvents. Additionally, their catalytic performance was carried out for the esterification reaction of acetic acid and butyl acetate. The highest conversion rate is 75.75% by using catalyst 1 . The esterification of butanol gave butyl acetate with 100% selectivity.

  15. Effects of some polymeric additives on the cocrystallization of caffeine

    NASA Astrophysics Data System (ADS)

    Chung, Jihae; Kim, Il Won

    2011-11-01

    Effects of polymeric additives on the model cocrystallization were examined. The model cocrystal was made from caffeine and oxalic acid, and poly(ethylene glycol) (PEG), poly( L-lactide) (PLLA), poly(ɛ-caprolactone) (PCL), and poly(acrylic acid) (PAA) were the additives. The cocrystals were formed as millimeter-sized crystals without additives, and they became microcrystals with PLLA and PCL, and nanocrystals with PAA. XRD and IR revealed that the cocrystal structure was unchanged despite the strong effects of the additives on the crystal morphology, although some decrease in crystallinity was observed with PAA as confirmed by DSC. The DSC study also showed that the cocrystal melted and recrystallized to form α-caffeine upon heating. The present study verified that the polymeric additives can be utilized to modulate the size and morphology of the cocrystals without interfering the intermolecular interactions essential to the integrity of the cocrystal structures.

  16. Synthesis and self-assembly of amphiphilic polymeric microparticles.

    PubMed

    Dendukuri, Dhananjay; Hatton, T Alan; Doyle, Patrick S

    2007-04-10

    We report the synthesis and self-assembly of amphiphilic, nonspherical, polymeric microparticles. Wedge-shaped particles bearing segregated hydrophilic and hydrophobic sections were synthesized in a microfludic channel by polymerizing across laminar coflowing streams of hydrophilic and hydrophobic polymers using continuous flow lithography (CFL). Particle monodispersity was characterized by measuring both the size of the particles formed and the extent of amphiphilicity. The coefficient of variation (COV) was found to be less than 2.5% in all measured dimensions. Particle structure was further characterized by measuring the curvature of the interface between the sections and the extent of cross-linking using FTIR spectroscopy. The amphiphilic particles were allowed to self-assemble in water or at water-oil interfaces. In water, the geometry of the particles enabled the formation of micelle-like structures, while in emulsions, the particles migrated to the oil-water interface and oriented themselves to minimize their surface energy.

  17. Spontaneous actin dynamics in contractile rings

    NASA Astrophysics Data System (ADS)

    Kruse, Karsten; Wollrab, Viktoria; Thiagarajan, Raghavan; Wald, Anne; Riveline, Daniel

    Networks of polymerizing actin filaments are known to be capable to self-organize into a variety of structures. For example, spontaneous actin polymerization waves have been observed in living cells in a number of circumstances, notably, in crawling neutrophils and slime molds. During later stages of cell division, they can also spontaneously form a contractile ring that will eventually cleave the cell into two daughter cells. We present a framework for describing networks of polymerizing actin filaments, where assembly is regulated by various proteins. It can also include the effects of molecular motors. We show that the molecular processes driven by these proteins can generate various structures that have been observed in contractile rings of fission yeast and mammalian cells. We discuss a possible functional role of each of these patterns. The work was supported by Agence Nationale de la Recherche, France, (ANR-10-LABX-0030-INRT) and by Deutsche Forschungsgemeinschaft through SFB1027.

  18. Modifying sulfomethylated alkali lignin by horseradish peroxidase to improve the dispersibility and conductivity of polyaniline

    NASA Astrophysics Data System (ADS)

    Yang, Dongjie; Huang, Wenjing; Qiu, Xueqing; Lou, Hongming; Qian, Yong

    2017-12-01

    Pine and wheat straw alkali lignin (PAL and WAL) were sulfomethylated to improve water solubility, polymerized with horseradish peroxidase (HRP) to improve the molecular weight (Mw) and applied to dope and disperse polyaniline (PANI). The structural effect of lignin from different origins on the reactivities of sulfomethylation and HRP polymerization was investigated. The results show that WAL with less methoxyl groups and lower Mw have higher reactivity in sulfomethylation (SWAL). More phenolic hydroxyl groups and lower Mw benefit the HRP polymerization of sulfomethylated PAL (SPAL). Due to the natural three-dimensional aromatic structure and introduced sulfonic groups, SPAL and SWAL could effectively dope and disperse PANI in water by π-π stacking and electrostatic interaction. HRP modified SPAL (HRP-SPAL) with much higher sulfonation degree and larger Mw significantly increased the conductivity and dispersibility of lignin/PANI composites.

  19. Pressure-induced polymerization of acetylene: Structure-directed stereoselectivity and a possible route to graphane

    DOE PAGES

    Sun, Jiangman; Dong, Xiao; Wang, Yajie; ...

    2017-05-02

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

  20. Syntheses of crosslinked latex nanoparticles using differential microemulsion polymerization

    NASA Astrophysics Data System (ADS)

    Hassmoro, N. F.; Rusop, M.; Abdullah, S.

    2013-06-01

    The differential microemulsion polymerization was used to synthesize latex nanoparticles. In this paper, 1, 3-butylene glycol dimethacrylate (1, 3-BGDMA) was used as a crosslinker respectively 1-5 weight% of monomer total. Butyl acrylate (BA), butyl methacrylate (BMA), and methacrylic acid (MAA) was used as the monomer. The thin film of latex nanoparticles were prepared by using spin coating method and have been dried at 100°C for 5 minutes. The amount of the crosslinker added in the polymerization was optimized and we found that the particle sizes fall in the range of 30-60 nm. The structural morphology of the uncrosslinked latex represented the most homogeneous image compared to the crosslinked latex. The effect of the amount of crosslinker on the particle sizes investigated by the Zeta-sizer Nano series while Atomic Force microscopy (AFM) was used to study the structural properties of latex nanoparticles.

  1. One method for life time estimation of a bucket wheel machine for coal moving

    NASA Astrophysics Data System (ADS)

    Vîlceanu, Fl; Iancu, C.

    2016-08-01

    Rehabilitation of outdated equipment with lifetime expired, or in the ultimate life period, together with high cost investments for their replacement, makes rational the efforts made to extend their life. Rehabilitation involves checking operational safety based on relevant expertise of metal structures supporting effective resistance and assessing the residual lifetime. The bucket wheel machine for coal constitute basic machine within deposits of coal of power plants. The estimate of remaining life can be done by checking the loading on the most stressed subassembly by Finite Element Analysis on a welding detail. The paper presents step-by-step the method of calculus applied in order to establishing the residual lifetime of a bucket wheel machine for coal moving using non-destructive methods of study (fatigue cracking analysis + FEA). In order to establish the actual state of machine and areas subject to study, was done FEA of this mining equipment, performed on the geometric model of mechanical analyzed structures, with powerful CAD/FEA programs. By applying the method it can be calculated residual lifetime, by extending the results from the most stressed area of the equipment to the entire machine, and thus saving time and money from expensive replacements.

  2. Identification of the microbial community composition and structure of coal-mine wastewater treatment plants.

    PubMed

    Ma, Qiao; Qu, Yuan-Yuan; Zhang, Xu-Wang; Shen, Wen-Li; Liu, Zi-Yan; Wang, Jing-Wei; Zhang, Zhao-Jing; Zhou, Ji-Ti

    2015-06-01

    The wastewater from coal-mine industry varies greatly and is resistant to biodegradation for containing large quantities of inorganic and organic pollutants. Microorganisms in activated sludge are responsible for the pollutants' removal, whereas the microbial community composition and structure are far from understood. In the present study, the sludges from five coal-mine wastewater treatment plants were collected and the microbial communities were analyzed by Illumina high-throughput sequencing. The diversities of these sludges were lower than that of the municipal wastewater treatment systems. The most abundant phylum was Proteobacteria ranging from 63.64% to 96.10%, followed by Bacteroidetes (7.26%), Firmicutes (5.12%), Nitrospira (2.02%), Acidobacteria (1.31%), Actinobacteria (1.30%) and Planctomycetes (0.95%). At genus level, Thiobacillus and Comamonas were the two primary genera in all sludges, other major genera included Azoarcus, Thauera, Pseudomonas, Ohtaekwangia, Nitrosomonas and Nitrospira. Most of these core genera were closely related with aromatic hydrocarbon degradation and denitrification processes. Identification of the microbial communities in coal-mine wastewater treatment plants will be helpful for wastewater management and control. Copyright © 2015 Elsevier GmbH. All rights reserved.

  3. Solvent refined coal (SRC) process. Annual technical progress report, January 1979-December 1979

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1980-11-01

    A set of statistically designed experiments was used to study the effects of several important operating variables on coal liquefaction product yield structures. These studies used a Continuous Stirred-Tank Reactor to provide a hydrodynamically well-defined system from which kinetic data could be extracted. An analysis of the data shows that product yield structures can be adequately represented by a correlative model. It was shown that second-order effects (interaction and squared terms) are necessary to provide a good model fit of the data throughout the range studied. Three reports were issued covering the SRC-II database and yields as functions of operatingmore » variables. The results agree well with the generally-held concepts of the SRC reaction process, i.e., liquid phase hydrogenolysis of liquid coal which is time-dependent, thermally activated, catalyzed by recycle ash, and reaction rate-controlled. Four reports were issued summarizing the comprehensive SRC reactor thermal response models and reporting the results of several studies made with the models. Analytical equipment for measuring SRC off-gas composition and simulated distillation of coal liquids and appropriate procedures have been established.« less

  4. Polystyrene/Fe3O4 magnetic emulsion and nanocomposite prepared by ultrasonically initiated miniemulsion polymerization.

    PubMed

    Qiu, Guihua; Wang, Qi; Wang, Chao; Lau, Willie; Guo, Yili

    2007-01-01

    Ultrasonically initiated miniemulsion polymerization of styrene in the presence of Fe3O4 nanoparticles was successfully employed to prepare polystyrene (PS)/Fe3O4 magnetic emulsion and nanocomposite. The effects of Fe3O4 nanoparticles on miniemulsion polymerization process, the structure, morphology and properties of PS/Fe3O4 nanocomposite were investigated. The increase in the amount of Fe3O4 nanoparticles drastically increases the polymerization rate due to that Fe3O4 nanoparticles increase the number of radicals and the cavitation bubbles. Polymerization kinetics of ultrasonically initiated miniemulsion polymerization is similar to that of conventional miniemulsion polymerization. PS/Fe3O4 magnetic emulsion consists of two types of particles: latex particles with Fe3O4 nanoparticles and latex particles with no encapsulated Fe3O4 nanoparticles. Fe3O4 nanoparticles lower the molecular weight of PS and broaden the molecular weight and particle size distribution. Thermal stability of PS/Fe3O4 nanocomposite increases with the increase in Fe3O4 content. PS/Fe3O4 emulsion and nanocomposite exhibit magnetic properties. PS/Fe3O4 magnetic particles can be separated from the magnetic emulsion by an external magnetic field and redispersed into the emulsion with agitation.

  5. A microtitre-based method for measuring the haem polymerization inhibitory activity (HPIA) of antimalarial drugs.

    PubMed

    Basilico, N; Pagani, E; Monti, D; Olliaro, P; Taramelli, D

    1998-07-01

    The malaria parasite metabolizes haemoglobin and detoxifies the resulting haem by polymerizing it to form haemozoin (malaria pigment). A polymer identical to haemozoin, beta-haematin, can be obtained in vitro from haematin at acidic pH. Quinoline-containing anti-malarials (e.g. chloroquine) inhibit the formation of either polymer. Haem polymerization is an essential and unique pharmacological target. To identify molecules with haem polymerization inhibitory activity (HPIA) and quantify their potency, we developed a simple, inexpensive, quantitative in-vitro spectrophotometric microassay of haem polymerization. The assay uses 96-well U-bottomed polystyrene microplates and requires 24 h and a microplate reader. The relative amounts of polymerized and unpolymerized haematin are determined, based on solubility in DMSO, by measuring absorbance at 405 nm in the presence of test compounds as compared with untreated controls. The final product (a solid precipitate of polymerized haematin) was validated using infrared spectroscopy and the assay proved reproducible; in this assay, activity could be partly predicted based on the compound's chemical structure. Both water-soluble and water-insoluble compounds can be quantified by this method. Although the throughput of this assay is lower than that of radiometric methods, the assay is easier to set up and cheaper, and avoids the problems related to radioactive waste disposal.

  6. Phosphoinositides and membrane curvature switch the mode of actin polymerization via selective recruitment of toca-1 and Snx9

    PubMed Central

    Gallop, Jennifer L.; Walrant, Astrid; Cantley, Lewis C.; Kirschner, Marc W.

    2013-01-01

    The membrane–cytosol interface is the major locus of control of actin polymerization. At this interface, phosphoinositides act as second messengers to recruit membrane-binding proteins. We show that curved membranes, but not flat ones, can use phosphatidylinositol 3-phosphate [PI(3)P] along with phosphatidylinositol 4,5-bisphosphate [PI(4,5)P2] to stimulate actin polymerization. In this case, actin polymerization requires the small GTPase cell cycle division 42 (Cdc42), the nucleation-promoting factor neural Wiskott–Aldrich syndrome protein (N-WASP) and the actin nucleator the actin-related protein (Arp) 2/3 complex. In liposomes containing PI(4,5)P2 as the sole phosphoinositide, actin polymerization requires transducer of Cdc42 activation-1 (toca-1). In the presence of phosphatidylinositol 3-phosphate, polymerization is both more efficient and independent of toca-1. Under these conditions, sorting nexin 9 (Snx9) can be implicated as a specific adaptor that replaces toca-1 to mobilize neural Wiskott–Aldrich syndrome protein and the Arp2/3 complex. This switch in phosphoinositide and adaptor specificity for actin polymerization from membranes has implications for how different types of actin structures are generated at precise times and locations in the cell. PMID:23589871

  7. Central Appalachia: Production potential of low-sulfur coal

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Watkins, J.

    The vast preponderance of eastern US low sulfur and 1.2-lbs SO{sub 2}/MMBtu compliance coal comes from a relatively small area composed of 14 counties located in eastern Kentucky, southern West Virginia and western Virginia. These 14 counties accounted for 68% of all Central Appalachian coal production in 1989 as well as 85% of all compliance coal shipped to electric utilities from this region. A property-by-property analysis of total production potential in 10 of the 14 counties (Floyd, Knott, Letcher, Harlan, Martin and Pike in Kentucky and Boone, Kanawha, Logan and Mingo in West Virginia) resulted in the following estimates ofmore » active and yet to be developed properties: (1) total salable reserves for all sulfur levels were 5.9 billion tons and (2) 1.2-lbs. SO{sub 2}/MMBtu compliance'' reserves totaled 2.38 billion tons. This potential supply of compliance coal is adequate to meet the expanded utility demand expected under acid rain for the next 20 years. Beyond 2010, compliance supplies will begin to reach depletion levels in some areas of the study region. A review of the cost structure for all active mines was used to categorize the cost structure for developing potential supplies. FOB cash costs for all active mines in the ten counties ranged from $15 per ton to $35 per ton and the median mine cost was about $22 per ton. A total of 47 companies with the ability to produce and ship coal from owned or leased reserves are active in the ten-county region. Identified development and expansion projects controlled by active companies are capable of expanding the region's current production level by over 30 million tons per year over the next twenty years. Beyond this period the issue of reserve depletion for coal of all sulfur levels in the ten county region will become a pressing issue. 11 figs., 12 tabs.« less

  8. Key Technologies and Applications of Gas Drainage in Underground Coal Mine

    NASA Astrophysics Data System (ADS)

    Zhou, Bo; Xue, Sheng; Cheng, Jiansheng; Li, Wenquan; Xiao, Jiaping

    2018-02-01

    It is the basis for the long-drilling directional drilling, precise control of the drilling trajectory and ensuring the effective extension of the drilling trajectory in the target layer. The technology can be used to complete the multi-branch hole construction and increase the effective extraction distance of the coal seam. The gas drainage and the bottom grouting reinforcement in the advanced area are realized, and the geological structure of the coal seam can be proved accurately. It is the main technical scheme for the efficient drainage of gas at home and abroad, and it is applied to the field of geological structure exploration and water exploration and other areas. At present, the data transmission method is relatively mature in the technology and application, including the mud pulse and the electromagnetic wave. Compared with the mud pulse transmission mode, the electromagnetic wave transmission mode has obvious potential in the data transmission rate and drilling fluid, and it is suitable for the coal mine. In this paper, the key technologies of the electromagnetic wave transmission mode are analyzed, including the attenuation characteristics of the electromagnetic transmission channel, the digital modulation scheme, the channel coding method and the weak signal processing technology. A coal mine under the electromagnetic wave drilling prototype is developed, and the ground transmission experiments and down hole transmission test are carried out. The main work includes the following aspects. First, the equivalent transmission line method is used to establish the electromagnetic transmission channel model of coal mine drilling while drilling, and the attenuation of the electromagnetic signal is measured when the electromagnetic channel measured. Second, the coal mine EM-MWD digital modulation method is developed. Third, the optimal linear block code which suitable for EM-MWD communication channel in coal mine is proposed. Fourth, the noise characteristics of well near horizontal directional drilling are analyzed, and the multi-stage filter method is proposed to suppress the natural potential and strong frequency interference signal. And the weak electromagnetic communication signal is extracted from the received signal. Finally, the detailed design of the electromagnetic wave while drilling is given.

  9. Analyses of geological and hydrodynamic controls on methane emissions experienced in a Lower Kittanning coal mine

    PubMed Central

    Karacan, C. Özgen; Goodman, Gerrit V.R.

    2015-01-01

    This paper presents a study assessing potential factors and migration paths of methane emissions experienced in a room-and-pillar mine in Lower Kittanning coal, Indiana County, Pennsylvania. Methane emissions were not excessive at idle mining areas, but significant methane was measured during coal mining and loading. Although methane concentrations in the mine did not exceed 1% limit during operation due to the presence of adequate dilution airflow, the source of methane and its migration into the mine was still a concern. In the course of this study, structural and depositional properties of the area were evaluated to assess complexity and sealing capacity of roof rocks. Composition, gas content, and permeability of Lower Kittanning coal, results of flotation tests, and geochemistry of groundwater obtained from observation boreholes were studied to understand the properties of coal and potential effects of old abandoned mines within the same area. These data were combined with the data obtained from exploration boreholes, such as depths, elevations, thicknesses, ash content, and heat value of coal. Univariate statistical and principal component analyses (PCA), as well as geostatistical simulations and co-simulations, were performed on various spatial attributes to reveal interrelationships and to establish area-wide distributions. These studies helped in analyzing groundwater quality and determining gas-in-place (GIP) of the Lower Kittanning seam. Furthermore, groundwater level and head on the Lower Kittanning coal were modeled and flow gradients within the study area were examined. Modeling results were interpreted with the structural geology of the Allegheny Group of formations above the Lower Kittanning coal to understand the potential source of gas and its migration paths. Analyses suggested that the source of methane was likely the overlying seams such as the Middle and Upper Kittanning coals and Freeport seams of the Allegheny Group. Simulated ground-water water elevations, gradients of groundwater flow, and the presence of recharge and discharge locations at very close proximity to the mine indicated that methane likely was carried with groundwater towards the mine entries. Existing fractures within the overlying strata and their orientation due to the geologic conditions of the area, and activation of slickensides between shale and sandstones due to differential compaction during mining, were interpreted as the potential flow paths. PMID:26478644

  10. Water-soluble polymers bearing phosphorylcholine group and other zwitterionic groups for carrying DNA derivatives.

    PubMed

    Lin, Xiaojie; Ishihara, Kazuhiko

    2014-01-01

    Water-soluble polymers with equal positive and negative charges in the same monomer unit, such as the phosphorylcholine group and other zwitterionic groups, exhibit promising potential in gene delivery with appreciable transfection efficiency, compared with the traditional poly(ethylene glycol)-based polycation-gene complexes. These zwitterionic polymers with various architectural structures and properties have been synthesized by various polymerization methods, such as conventional radical polymerization, atom-transfer radical-polymerization, reversible addition-fragmentation chain-transfer polymerization, and nitroxide-mediated radical polymerization. These techniques have been used to efficiently facilitate gene therapy by fabrication of non-viral vectors with high cytocompatibility, large gene-carrying capacity, effective cell-membrane permeability, and in vivo gene-loading/releasing functionality. Zwitterionic polymer-based gene delivery vectors systems can be categorized into soluble-polymer/gene mixing, molecular self-assembly, and polymer-gene conjugation systems. This review describes the preparation and characterization of various zwitterionic polymer-based gene delivery vectors, specifically water-soluble phospholipid polymers for carrying gene derivatives.

  11. A novel chiral separation material: polymerized organogel formed by chiral gelators for the separation of D- and L-phenylalanine.

    PubMed

    Fu, Xinjian; Yang, Yang; Wang, Ningxia; Wang, Hong; Yang, Yajiang

    2007-01-01

    N-Stearine-N'-stearyl-L-phenylalanine, a chiral compound, was synthesized and used as a gelator for the gelation of polymerizable solvents, such as ss-hydroxyethyl methacrylate (HEMA), styrene, etc. The scanning electron microscope (SEM) images of the gelator aggregates show fibril-like helices, typical chiral aggregates with diameters of 100-200 nm. The solvent molecules were immobilized by capillary forces in the three-dimensional network structures of the organogels. The HEMA organogels containing crosslinker polyethylene glycol dimethacrylates (PEG200DMA) were subsequently polymerized by in situ UV irradiation. A porous polymerized organogels were obtained after removal of gelator aggregates through ethanol extraction. The chiral separation of D- and L-phenylalanine was carried out by the adsorption of the polymerized organogels. The adsorption efficiency of L-phenylalanine on the polymerized organogels was found to be dependent on the concentration of the gelator and crosslinker. (c) 2007 John Wiley & Sons, Ltd.

  12. Synthesis and characterization of polymeric V2O5/AlO(OH) with nanopores on alumina support.

    PubMed

    Ahmad, A L; Abd Shukor, S R; Leo, C P

    2006-12-01

    Polymeric vanadium pentoxide gel was formed via the reaction of V2O5 powder with hydrogen peroxide. The polymeric vanadium pentoxide gel was then dispersed in alumina gel. Different vanadium loading composites were coated on alumina support and calcined at 500 degrees C for 1 hr. These composite layers were characterized using TGA, FT-IR, XRD, SEM, and Autosorb. It was found that the lamellar structure of polymerized vanadium pentoxide was retained in the inorganic matrix. Crystalline alumina in gamma phase was formed after calcinations. However, the vanadium-alumina mixed oxides are lack of the well defined PXRD peaks for polycrystalline V2O5. This is possibly because the vanadia species are highly dispersed in the alumina matrix or the vanadia species are dispersed as crystalline which is smaller than 4 nm. In addition, the imbedded polymeric vanadium oxide improved the specific area and average pore diameter of the composite layer.

  13. Surface water retardation around single-chain polymeric nanoparticles: critical for catalytic function?

    PubMed

    Stals, Patrick J M; Cheng, Chi-Yuan; van Beek, Lotte; Wauters, Annelies C; Palmans, Anja R A; Han, Songi; Meijer, E W

    2016-03-01

    A library of water-soluble dynamic single-chain polymeric nanoparticles (SCPN) was prepared using a controlled radical polymerisation technique followed by the introduction of functional groups, including probes at targeted positions. The combined tools of electron paramagnetic resonance (EPR) and Overhauser dynamic nuclear polarization (ODNP) reveal that these SCPNs have structural and surface hydration properties resembling that of enzymes.

  14. Structural and Functional Studies of H. seropedicae RecA Protein - Insights into the Polymerization of RecA Protein as Nucleoprotein Filament.

    PubMed

    Leite, Wellington C; Galvão, Carolina W; Saab, Sérgio C; Iulek, Jorge; Etto, Rafael M; Steffens, Maria B R; Chitteni-Pattu, Sindhu; Stanage, Tyler; Keck, James L; Cox, Michael M

    2016-01-01

    The bacterial RecA protein plays a role in the complex system of DNA damage repair. Here, we report the functional and structural characterization of the Herbaspirillum seropedicae RecA protein (HsRecA). HsRecA protein is more efficient at displacing SSB protein from ssDNA than Escherichia coli RecA protein. HsRecA also promotes DNA strand exchange more efficiently. The three dimensional structure of HsRecA-ADP/ATP complex has been solved to 1.7 Å resolution. HsRecA protein contains a small N-terminal domain, a central core ATPase domain and a large C-terminal domain, that are similar to homologous bacterial RecA proteins. Comparative structural analysis showed that the N-terminal polymerization motif of archaeal and eukaryotic RecA family proteins are also present in bacterial RecAs. Reconstruction of electrostatic potential from the hexameric structure of HsRecA-ADP/ATP revealed a high positive charge along the inner side, where ssDNA is bound inside the filament. The properties of this surface may explain the greater capacity of HsRecA protein to bind ssDNA, forming a contiguous nucleoprotein filament, displace SSB and promote DNA exchange relative to EcRecA. Our functional and structural analyses provide insight into the molecular mechanisms of polymerization of bacterial RecA as a helical nucleoprotein filament.

  15. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bowley, S.; Okumura, N; Lord, S

    'A:a' knob-hole interactions and D:D interfacial interactions are important for fibrin polymerization. Previous studies with recombinant ?N308K fibrinogen, a substitution at the D:D interface, showed impaired polymerization. We examined the molecular basis for this loss of function by solving the crystal structure of ?N308K fragment D. In contrast to previous fragment D crystals, the ?N308K crystals belonged to a tetragonal space group with an unusually long unit cell (a = b = 95 Angstroms, c = 448.3 Angstroms). Alignment of the normal and ?N308K structures showed the global structure of the variant was not changed and the knob 'A' peptidemore » GPRP was bound as usual to hole 'a'. The substitution introduced an elongated positively charged patch in the D:D region. The structure showed novel, symmetric D:D crystal contacts between ?N308K molecules, indicating the normal asymmetric D:D interface in fibrin would be unstable in this variant. We examined GPRP binding to ?N308K in solution by plasmin protection assay. The results showed weaker peptide binding, suggesting that 'A:a' interactions were altered. We examined fibrin network structures by scanning electron microscopy and found the variant fibers were thicker and more heterogeneous than normal fibers. Considered together, our structural and biochemical studies indicate both 'A:a' and D:D interactions are weaker. We conclude that stable protofibrils cannot assemble from ?N308K monomers, leading to impaired polymerization.« less

  16. Photonic devices based on patterning by two photon induced polymerization techniques

    NASA Astrophysics Data System (ADS)

    Fortunati, I.; Dainese, T.; Signorini, R.; Bozio, R.; Tagliazucca, V.; Dirè, S.; Lemercier, G.; Mulatier, J.-C.; Andraud, C.; Schiavuta, P.; Rinaldi, A.; Licoccia, S.; Bottazzo, J.; Franco Perez, A.; Guglielmi, M.; Brusatin, G.

    2008-04-01

    Two and three dimensional structures with micron and submicron resolution have been achieved in commercial resists, polymeric materials and sol-gel materials by several lithographic techniques. In this context, silicon-based sol-gel materials are particularly interesting because of their versatility, chemical and thermal stability, amount of embeddable active compounds. Compared with other micro- and nano-fabrication schemes, the Two Photon Induced Polymerization is unique in its 3D processing capability. The photopolymerization is performed with laser beam in the near-IR region, where samples show less absorption and less scattering, giving rise to a deeper penetration of the light. The use of ultrashort laser pulses allows the starting of nonlinear processes like multiphoton absorption at relatively low average power without thermally damaging the samples. In this work we report results on the photopolymerization process in hybrid organic-inorganic films based photopolymerizable methacrylate-containing Si-nanobuilding blocks. Films, obtained through sol-gel synthesis, are doped with a photo-initiator allowing a radical polymerization of methacrylic groups. The photo-initiator is activated by femtosecond laser source, at different input energies. The development of the unexposed regions is performed with a suitable solvent and the photopolymerized structures are characterized by microscopy techniques.

  17. Precision Aliphatic Polyesters with Alternating Microstructures via Cross-Metathesis Polymerization: An Event of Sequence Control.

    PubMed

    Li, Zi-Long; Zeng, Fu-Rong; Ma, Ji-Mei; Sun, Lin-Hao; Zeng, Zhen; Jiang, Hong

    2017-06-01

    Sequence-regulated polymerization is realized upon sequential cross-metathesis polymerization (CMP) and exhaustive hydrogenation to afford precision aliphatic polyesters with alternating sequences. This strategy is particularly suitable for the arrangement of well-known monomer units including glycolic acid, lactic acid, and caprolactic acid on polymer chain in a predetermined sequence. First of all, structurally asymmetric monomers bearing acrylate and α-olefin terminuses are generated in an efficient and straightforward fashion. Subsequently, cross-metathesis (co)polymerization of M1 and M2 using the Hoveyda-Grubbs second-generation catalyst (HG-II) furnishes P1-P3, respectively. Finally, hydrogenation yields the desired saturated polyesters HP1-HP3. It is noteworthy that the ε-caprolactone-derived unit is generated in situ rather than introduced to tailor-made monomers prior to CMP. NMR and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) results verify the microstructural periodicity of these precision polyesters. Differential scanning calorimetry (DSC) results reflect that polyesters without methyl side groups exhibit crystallinity, and unsaturated polyester samples show higher glass transition temperatures than their hydrogenated counterparts owing to structural rigidity. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Stratigraphy and structure of coalbed methane reservoirs in the United States: an overview

    USGS Publications Warehouse

    Pashin, J.C.

    1998-01-01

    Stratigraphy and geologic structure determine the shape, continuity and permeability of coal and are therefore critical considerations for designing exploration and production strategies for coalbed methane. Coal in the United states is dominantly of Pennsylvanian, Cretaceous and Tertiary age, and to date, more than 90% of the coalbed methane produced is from Pennsylvanian and cretaceous strata of the Black Warrior and San Juan Basins. Investigations of these basins establish that sequence stratigraphy is a promising approach for regional characterization of coalbed methane reservoirs. Local stratigraphic variation within these strata is the product of sedimentologic and tectonic processes and is a consideration for selecting completion zones. Coalbed methane production in the United States is mainly from foreland and intermontane basins containing diverse compression and extensional structures. Balanced structural models can be used to construct and validate cross sections as well as to quantify layer-parallel strain and predict the distribution of fractures. Folds and faults influence gas and water production in diverse ways. However, interwell heterogeneity related to fractures and shear structures makes the performance of individual wells difficult to predict.Stratigraphy and geologic structure determine the shape, continuity and permeability of coal and are therefore critical considerations for designing exploration and production strategies for coalbed methane. Coal in the United States is dominantly of Pennsylvanian, Cretaceous and Tertiary age, and to date, more than 90% of the coalbed methane produced is from Pennsylvanian and Cretaceous strata of the Black Warrior and San Juan Basins. Investigations of these basins establish that sequence stratigraphy is a promising approach for regional characterization of coalbed methane reservoirs. Local stratigraphic variation within these strata is the product of sedimentologic and tectonic processes and is a consideration for selecting completion zones. Coalbed methane production in the United States is mainly from foreland and intermontane basins containing diverse compressional and extensional structures. Balanced structural models can be used to construct and validate cross sections as well as to quantify layer-parallel strain and predict the distribution of fractures. Folds and faults influence gas and water production in diverse ways. However, interwell heterogeneity related to fractures and shear structures makes the performance of individual wells difficult to predict.

  19. In-situ Polymerization of Polyaniline/Polypyrrole Copolymer using Different Techniques

    NASA Astrophysics Data System (ADS)

    Hammad, A. S.; Noby, H.; Elkady, M. F.; El-Shazly, A. H.

    2018-01-01

    The morphology and surface area of the poly(aniline-co-pyrrole) copolymer (PANPY) are important properties which improve the efficiency of the copolymer in various applications. In this investigation, different techniques were employed to produce PANPY in different morphologies. Aniline and pyrrole were used as monomers, and ammonium peroxydisulfate (APS) was used as an oxidizer with uniform molar ratio. Rapid mixing, drop-wise mixing, and supercritical carbon dioxide (ScCO2) polymerization techniques were appointed. The chemical structure, crystallinity, porosity, and morphology of the composite were distinguished by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), Brunauer, Emmett and Teller (BET) analysis, and transmission electron microscopy (TEM) respectively. The characterization tests indicated that the polyaniline/polypyrrole copolymer was successfully prepared with different morphologies. Based on the obtained TEM, hollow nanospheres were formed using rapid mixing technique with acetic acid that have a diameter of 75 nm and thickness 26 nm approximately. Also, according to the XRD, the produced structures have a semi- crystalline structure. The synthesized copolymer with ScCO2-assisted polymerization technique showed improved surface area (38.1 m2/g) with HCl as dopant.

  20. Mechanistic Studies of ε-Caprolactone Polymerization by (salen)AlOR Complexes and a Predictive Model for Cyclic Ester Polymerizations

    PubMed Central

    2016-01-01

    Aluminum alkoxide complexes (2) of salen ligands with a three-carbon linker and para substituents having variable electron-withdrawing capabilities (X = NO2, Br, OMe) were prepared, and the kinetics of their ring-opening polymerization (ROP) of ε-caprolactone (CL) were investigated as a function of temperature, with the aim of drawing comparisons to similar systems with two-carbon linkers investigated previously (1). While 1 and 2 exhibit saturation kinetics and similar dependences of their ROP rates on substituents X (invariant Keq, similar Hammett ρ = +1.4(1) and 1.2(1) for k2, respectively), ROP by 2 was significantly faster than for 1. Theoretical calculations confirm that, while the reactant structures differ, the transition state geometries are quite similar, and by analyzing the energetics of the involved distortions accompanying the structural changes, a significant contribution to the basis for the rate differences was identified. Using this knowledge, a simplified computational method for evaluating ligand structural influences on cyclic ester ROP rates is proposed that may have utility for future catalyst design. PMID:26900488

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