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Sample records for hp desulfuration directe

  1. 45. 800 H.P. WATER WHEEL UNIT (LEFT HAND) DIRECT CONNECTED ...

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

    45. 800 H.P. WATER WHEEL UNIT (LEFT HAND) DIRECT CONNECTED TO A 500 K.W. G.E. CO. GENERATOR, SPEED 176 R.P.M., HEAD OF WATER 305 FT EFF., FOR SANTA ANA RIVER NO. 2 PLANT. ABNER DOBLE CO., ENGINEERS, SAN FRANCISCO, AUG. 29, 1904. TRACED FROM DOBLE BLUE PRINT, SEPT. 9, 1911. SCE drawing no. 5698. - Santa Ana River Hydroelectric System, SAR-2 Powerhouse, Redlands, San Bernardino County, CA

  2. Biosynthesis of platform chemical 3-hydroxypropionic acid (3-HP) directly from CO2 in cyanobacterium Synechocystis sp. PCC 6803.

    PubMed

    Wang, Yunpeng; Sun, Tao; Gao, Xingyan; Shi, Mengliang; Wu, Lina; Chen, Lei; Zhang, Weiwen

    2016-03-01

    3-hydroxypropionic acid (3-HP) is an important platform chemical with a wide range of applications. So far large-scale production of 3-HP has been mainly through petroleum-based chemical processes, whose sustainability and environmental issues have attracted widespread attention. With the ability to fix CO2 directly, cyanobacteria have been engineered as an autotrophic microbial cell factory to produce fuels and chemicals. In this study, we constructed the biosynthetic pathway of 3-HP in cyanobacterium Synechocystis sp. PCC 6803, and then optimized the system through the following approaches: i) increasing expression of malonyl-CoA reductase (MCR) gene using different promoters and cultivation conditions; ii) enhancing supply of the precursor malonyl-CoA by overexpressing acetyl-CoA carboxylase and biotinilase; iii) improving NADPH supply by overexpressing the NAD(P) transhydrogenase gene; iv) directing more carbon flux into 3-HP by inactivating the competing pathways of PHA and acetate biosynthesis. Together, the efforts led to a production of 837.18 mg L(-1) (348.8 mg/g dry cell weight) 3-HP directly from CO2 in Synechocystis after 6 days cultivation, demonstrating the feasibility photosynthetic production of 3-HP directly from sunlight and CO2 in cyanobacteria. In addition, the results showed that overexpression of the ribulose-1, 5-bisphosphate carboxylase/oxygenase (Rubisco) gene from Anabaena sp. PCC 7120 and Synechococcus sp. PCC 7942 led to no increase of 3-HP production, suggesting CO2 fixation may not be a rate-limiting step for 3-HP biosynthesis in Synechocystis.

  3. Advanced sulfur control concepts in hot-gas desulfurization technology: Phase 1, Feasibility of the direct production of elemental sulfur during the regeneration of high temperature desulfurization sorbents

    SciTech Connect

    Lopez, A.; White, J.; Groves, F.R.; Harrison, D.P.

    1994-10-01

    This topical report de-scribes the results of Phase 1 research performed during the first six months of a three-year contract to study the feasibility of the direct production of elemental sulfur during the regeneration of high temperature desulfurization sorbents. Much effort has gone into the development of a high-temperature meal oxide sorbent process for removal of H{sub 2}S from the coal gas. A number of sorbents based upon metals such as zinc, iron, manganese and others have been studied. In order for high temperature desulfurization to be economical it is necessary that the sorbents be regenerated to permit multicycle operation. Current methods of sorbent regeneration involve oxidation of the metal sulfide to reform the metal oxide and free the sulfur as SO{sub 2}. An alternate regeneration process in which the sulfur is liberated in elemental form is preferable. The overall objective of the current research is to study simpler and economically superior processing of known sorbents capable of producing elemental sulfur during regeneration. This topical report summarizes the first steps of this effort. A literature search has been completed to identify possible regeneration concepts and to collect relevant thermodynamic, kinetic, and process data. Three concepts involving reaction with SO{sub 2}, partial oxidation using an O{sub 2} {minus} H{sub 2}O mixture, and steam regeneration have been identified. The first two concepts result in the direct production of elemental sulfur while H{sub 2}S is the product of steam regeneration. This concept is of potential interest, however, since existing Claus technology can be used to convert H{sub 2}S to elemental sulfur. Following the literature search, a thermodynamic analysis, based upon free-energy minimization was carried out to evaluate candidate sorbents for possible use with the three regeneration concepts.

  4. Direct spectral/hp element simulation of piloted jet non-premixed flames

    NASA Astrophysics Data System (ADS)

    Nastase, Cristian R.

    2004-11-01

    The spectral/hp element method is used for direct numerical simulation (DNS) of piloted non premixed methane jet flames. This method combines the accuracy of spectral methods with versatility of finite element methods, and allows accurate simulations of complex flows on structured and unstructured grids. Here, the methodology is extended for simulation of multi-species, reactive flows using the discontinuous Galerkin formulation. Parallel computation is performed via MPI standards coupled with a domain decomposition methodology. The overall computational scheme allows for an efficient partitioning of the flow configuration. Tests performed with up to 64 processors show quasi-linear parallel performance and scalability. The flame configurations are similar to the piloted jet non-premixed flame considered at the Combustion Research Facility at the Sandia National Laboratories. For a momentum dominated flame, the simulated results portray many of the features observed experimentally. This pertains to both the spatial and the compositional structures of the flow. For a buoyancy controlled flame (at elevated gravity levels), the results indicate an increase in both the turbulence levels and flow acceleration. Departure from equilibrium, including localized extinction is observed on a significant portion of this flame.

  5. 76 FR 28635 - Airworthiness Directives; British Aerospace Regional Aircraft Model HP.137 Jetstream Mk.1...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-18

    ... bores for cracks. Do the inspections following British Aerospace Jetstream Series 3100 & 3200 Service... the MLG leg pivot beam fastener bores for cracks. Do the inspections following British Aerospace...-004-AD; Amendment 39-16699; AD 2011-11-01] RIN 2120-AA64 Airworthiness Directives; British...

  6. The Biocatalytic Desulfurization Project

    SciTech Connect

    David Nunn; James Boltz; Philip M. DiGrazia; Larry Nace

    2006-03-03

    The material in this report summarizes the Diversa technical effort in development of a biocatalyst for the biodesulfurization of Petro Star diesel as well as an economic report of standalone and combined desulfurization options, prepared by Pelorus and Anvil, to support and inform the development of a commercially viable process. We will discuss goals of the projected as originally stated and their modification as guided by parallel efforts to evaluate commercialization economics and process parameters. We describe efforts to identify novel genes and hosts for the generation of an optimal biocatalyst, analysis of diesel fuels (untreated, chemically oxidized and hydrotreated) for organosulfur compound composition and directed evolution of enzymes central to the biodesulfurization pathway to optimize properties important for their use in a biocatalyst. Finally we will summarize the challenges and issues that are central to successful development of a viable biodesulfurization process.

  7. An adaptable parallel algorithm for the direct numerical simulation of incompressible turbulent flows using a Fourier spectral/hp element method and MPI virtual topologies.

    PubMed

    Bolis, A; Cantwell, C D; Moxey, D; Serson, D; Sherwin, S J

    2016-09-01

    A hybrid parallelisation technique for distributed memory systems is investigated for a coupled Fourier-spectral/hp element discretisation of domains characterised by geometric homogeneity in one or more directions. The performance of the approach is mathematically modelled in terms of operation count and communication costs for identifying the most efficient parameter choices. The model is calibrated to target a specific hardware platform after which it is shown to accurately predict the performance in the hybrid regime. The method is applied to modelling turbulent flow using the incompressible Navier-Stokes equations in an axisymmetric pipe and square channel. The hybrid method extends the practical limitations of the discretisation, allowing greater parallelism and reduced wall times. Performance is shown to continue to scale when both parallelisation strategies are used.

  8. An adaptable parallel algorithm for the direct numerical simulation of incompressible turbulent flows using a Fourier spectral/hp element method and MPI virtual topologies

    NASA Astrophysics Data System (ADS)

    Bolis, A.; Cantwell, C. D.; Moxey, D.; Serson, D.; Sherwin, S. J.

    2016-09-01

    A hybrid parallelisation technique for distributed memory systems is investigated for a coupled Fourier-spectral/hp element discretisation of domains characterised by geometric homogeneity in one or more directions. The performance of the approach is mathematically modelled in terms of operation count and communication costs for identifying the most efficient parameter choices. The model is calibrated to target a specific hardware platform after which it is shown to accurately predict the performance in the hybrid regime. The method is applied to modelling turbulent flow using the incompressible Navier-Stokes equations in an axisymmetric pipe and square channel. The hybrid method extends the practical limitations of the discretisation, allowing greater parallelism and reduced wall times. Performance is shown to continue to scale when both parallelisation strategies are used.

  9. Crude oil desulfurization

    NASA Technical Reports Server (NTRS)

    Kalvinskas, J. J.; Hsu, G. C.; Ernest, J. B. (Inventor)

    1982-01-01

    High sulfur crude oil is desulfurized by a low temperature (25-80 C.) chlorinolysis at ambient pressure in the absence of organic solvent or diluent but in the presence of water (water/oil=0.3) followed by a water and caustic wash to remove sulfur and chlorine containing reaction products. The process described can be practiced at a well site for the recovery of desulfurized oil used to generate steam for injection into the well for enhanced oil recovery.

  10. [A method of desulfurization with calcium sulfite and it's mechanism].

    PubMed

    Tong, Z; Chen, Z; Peng, Z

    2001-09-01

    Directing to the scaling problem lying in wet desulfurization with lime slurry, a method of desulfurization with calcium sulfite was proposed. Reaction mechanism and the effects of different conditions on desulfurization efficiency were studied. The optimum conditions were obtained, i.e. air velocity of 2.75 m/s in empty tower, L/G = 3.0 L/m3, solid content 6.7%, air temperature 31 degrees C, concentration inlet of SO2 1500 x 10(-6) and inlet suspension pH of 8.0. Under the conditions, the desulfurization efficiency was about 87%. The presented method theoretically and practically solved the scaling problems, which is a novel indirect lime-method with Ca-contained material as desulfurization agent.

  11. THE BIOCATALYTIC DESULFURIZATION PROJECT

    SciTech Connect

    Steven E. Bonde; David Nunn

    2003-01-01

    During the first quarter of the Biological Desulfurization project several activities were pursued. A project kickoff meeting was held at the Diversa facility in San Diego, CA. Activities that were in process before the meeting and begun afterwards by Diversa Corporation and Petro Star Inc. include: Technology transfer in the form of information generated by Enchira to Diversa, the purchase and installation of equipment by Diversa, development of synthetic methods and preparation of organo-sulfur substrates for use in determining enzyme activities, production of extract via Petro Star's CED process, detailed analysis of Petro Star Inc. diesel and CED extract, and several activities in molecular biology. Diversa Corporation, in the area of molecular biology, engaged in several activities in support of the task list of the contract. These included: construction of a genomic library; development and utilization of a sequence-based gene discovery effort; a parallel discovery approach based on functional expression of enzymes with the ability to oxidize organosulfur compounds. Biodesulfurization genes have already been identified and are being sequenced and subcloned for expression in heterologous biological hosts. Diversa has evaluated and adapted assays developed by Enchira used to assess the activities of DBT and DBTO{sub 2} monooxygenases. Finally, Diversa personnel have developed two novel selection/screen strategies for the improvement of biocatalyst strains by directed evolution.

  12. Fluidized bed coal desulfurization

    NASA Technical Reports Server (NTRS)

    Ravindram, M.

    1983-01-01

    Laboratory scale experiments were conducted on two high volatile bituminous coals in a bench scale batch fluidized bed reactor. Chemical pretreatment and posttreatment of coals were tried as a means of enhancing desulfurization. Sequential chlorination and dechlorination cum hydrodesulfurization under modest conditions relative to the water slurry process were found to result in substantial sulfur reductions of about 80%. Sulfur forms as well as proximate and ultimate analyses of the processed coals are included. These studies indicate that a fluidized bed reactor process has considerable potential for being developed into a simple and economic process for coal desulfurization.

  13. Enzymatic desulfurization of coal

    SciTech Connect

    Boyer, Y.N.; Crooker, S.C.; Kitchell, J.P.; Nochur, S.V.

    1991-05-16

    The overall objective of this program was to investigate the feasibility of an enzymatic desulfurization process specifically intended for organic sulfur removal from coal. Toward that end, a series of specific objectives were defined: (1) establish the feasibility of (bio)oxidative pretreatment followed by biochemical sulfate cleavage for representative sulfur-containing model compounds and coals using commercially-available enzymes; (2) investigate the potential for the isolation and selective use of enzyme preparations from coal-utilizing microbial systems for desulfurization of sulfur-containing model compounds and coals; and (3) develop a conceptual design and economic analysis of a process for enzymatic removal of organic sulfur from coal. Within the scope of this program, it was proposed to carry out a portion of each of these efforts concurrently. (VC)

  14. Enzymatic desulfurization of coal

    SciTech Connect

    Marquis, J.K. . School of Medicine); Kitchell, J.P. )

    1988-12-15

    Our current efforts to develop clean coal technology emphasize the advantages of enzymatic desulfurization techniques and have specifically addressed the potential of using partially-purified extracellular microbial enzymes or commercially available enzymes. Our work is focused on the treatment of model'' organic sulfur compounds such as dibenzothiophene (DBT) and ethylphenylsulfide (EPS). Furthermore, we are designing experiments to facilitate the enzymatic process by means of a hydrated organic solvent matrix.

  15. Fluidized bed desulfurization

    NASA Technical Reports Server (NTRS)

    Ravindram, M.; Kallvinskas, J. J. (Inventor)

    1985-01-01

    High sulfur content carbonaceous material, such as coal is desulfurized by continuous fluidized suspension in a reactor with chlorine gas, inert dechlorinating gas and hydrogen gas. A source of chlorine gas, a source of inert gas and a source of hydrogen gas are connected to the bottom inlet through a manifold and a heater. A flow controler operates servos in a manner to continuously and sequentially suspend coal in the three gases. The sulfur content is reduced at least 50% by the treatment.

  16. Microbial desulfurization of coal

    NASA Technical Reports Server (NTRS)

    Dastoor, M. N.; Kalvinskas, J. J.

    1978-01-01

    Experiments indicate that several sulfur-oxidizing bacteria strains have been very efficient in desulfurizing coal. Process occurs at room temperature and does not require large capital investments of high energy inputs. Process may expand use of abundant reserves of high-sulfur bituminous coal, which is currently restricted due to environmental pollution. On practical scale, process may be integrated with modern coal-slurry transportation lines.

  17. Coal Liquefaction desulfurization process

    DOEpatents

    Givens, Edwin N.

    1983-01-01

    In a solvent refined coal liquefaction process, more effective desulfurization of the high boiling point components is effected by first stripping the solvent-coal reacted slurry of lower boiling point components, particularly including hydrogen sulfide and low molecular weight sulfur compounds, and then reacting the slurry with a solid sulfur getter material, such as iron. The sulfur getter compound, with reacted sulfur included, is then removed with other solids in the slurry.

  18. Enzymatic desulfurization of coal

    SciTech Connect

    Boyer, Y.N.; Crooker, S.C.; Kitchell, J.P.; Nochur, S.V. ); Marquis, J.K. . School of Medicine)

    1989-06-16

    Our current efforts to develop clean coal technology emphasize the advantages of enzymatic desulfurization techniques and have specifically addressed the potential of using partially-purified extracellular microbial enzymes as well as commercially available enzymes. Our work is focused on the treatment of model'' organic sulfur compounds such as dibenzothiophene (DBT) and ethylphenylsulfide (EPS). Furthermore, we are designing experiments to facilitate the enzymatic process by means of a hydrated organic solvent matrix.

  19. THE BIOCATALYTIC DESULFURIZATION PROJECT

    SciTech Connect

    Scott Collins; David Nunn

    2003-10-01

    The analysis of Petro Star diesel sulfur species is complete and a report is attached. Further analytical efforts will concentrate on characterization of diesel fuel, hydrodesulfurized to varying degrees, in order to determine sulfur species that may be problematic to hydrogen treatment and represent potential target substrates for biodesulfurization in a combined HDS-BDS process. Quotes have been received and are being considered for the partial treatment of Petro Star Inc. marine diesel fuel. Direction of research is changing slightly; economic analysis of the hyphenated--BDSHDS, BDS-CED--has shown the highest probability of success to be with a BDS-HDS process where the biodesulfurization precedes hydrodesulfurization. Thus, the microorganisms will be tailored to focus on those compounds that tend to be recalcitrant to hydrodesulfurization and decrease the severity of the hydrodesulfurization step. A separate, detailed justification for this change is being prepared. Research activities have continued in the characterization of the desulfurization enzymes from multiple sources. Genes for all DszA, -B, -C and -D enzymes (and homologs) have been cloned and expressed. Activity determinations, on a variety of substituted benzothiophene and dibenzothiophene substrates, have been carried out and continue. In addition, chemical synthesis efforts have been carried out to generate additional substrates for analytical standards and activity determinations. The generation of a GSSM mutant library of the ''Rhodococcus IGTS8 dszA'' gene has been completed and development of protocols for a high throughput screen to expand substrate specificity are nearing completion. In an effort to obtain improved hosts as biocatalyst, one hundred-thirty ''Rhodococcus'' and related strains are being evaluated for growth characteristics and other criteria deemed important for an optimal biocatalyst strain. We have also begun an effort to generate derivatives of the entire IGTS8 BDS plasmid

  20. Coal desulfurization with iron pentacarbonyl

    NASA Technical Reports Server (NTRS)

    Hsu, G. C.

    1979-01-01

    Coal desulfurization with iron pentacarbonyl treatment under mild conditions removes up to eighty percent of organic sulfur. Preliminary tests on treatment process suggest it may be economical enough to encourage investigation of use for coal desulfurization. With mild operating conditions, process produces environmentally-acceptable clean coal at reasonable cost.

  1. Coal desulfurization by cyclonic whirl

    SciTech Connect

    Jianguo, Y.; Wenjun, Z.; Yuling, W.

    1999-07-01

    The crux of coal desulfurization is how to improve separation efficiency for 3--0.1mm materials. Cyclonic whirl produce centrifugal force and shearing force, heavy medium cyclone uses former, and cyclone flotation column uses both of them. A new system with heavy medium cyclone and cyclone flotation column is provided and testified to be very efficient in commercial desulfurization.

  2. Clerget 100 hp heavy-oil engine

    NASA Technical Reports Server (NTRS)

    Leglise, Pierre

    1931-01-01

    A complete technical description of the Clerget heavy-oil engine is presented along with the general characteristics. The general characteristics are: 9 cylinders, bore 120 mm, stroke 130 mm, four-stroke cycle engine, rated power limited to 100 hp at 1800 rpm; weight 228 kg; propeller with direct drive and air cooling. Moving parts, engine block, and lubrication are all presented.

  3. Differential Cooperation between Heterochromatin Protein HP1 Isoforms and MyoD in Myoblasts*S⃞

    PubMed Central

    Yahi, Hakima; Fritsch, Lauriane; Philipot, Ophelie; Guasconi, Valentina; Souidi, Mouloud; Robin, Philippe; Polesskaya, Anna; Losson, Regine; Harel-Bellan, Annick; Ait-Si-Ali, Slimane

    2008-01-01

    Mechanisms of transcriptional repression are important during cell differentiation. Mammalian heterochromatin protein 1 isoforms HP1α, HP1β, and HP1γ play important roles in the regulation of chromatin structure and function. We explored the possibility of different roles for the three HP1 isoforms in an integrated system, skeletal muscle terminal differentiation. In this system, terminal differentiation is initiated by the transcription factor MyoD, whose target genes remain mainly silent until myoblasts are induced to differentiate. Here we show that HP1α and HP1β isoforms, but not HP1γ, interact with MyoD in myoblasts. This interaction is direct, as shown using recombinant proteins in vitro. A gene reporter assay revealed that HP1α and HP1β, but not HP1γ, inhibit MyoD transcriptional activity, suggesting a model in which MyoD could serve as a bridge between nucleosomes and chromatin-binding proteins such as HDACs and HP1. Chromatin immunoprecipitation assays show a preferential recruitment of HP1 proteins on MyoD target genes in proliferating myoblasts. Finally, modulation of HP1 protein level impairs MyoD target gene expression and muscle terminal differentiation. Together, our data show a nonconventional interaction between HP1 and a tissue-specific transcription factor, MyoD. In addition, they strongly suggest that HP1 isoforms play important roles during muscle terminal differentiation in an isoform-dependent manner. PMID:18599480

  4. Irradiation pretreatment for coal desulfurization

    NASA Technical Reports Server (NTRS)

    Hsu, G. C.

    1979-01-01

    Process using highly-penetrating nuclear radiation (Beta and Gamma radiation) from nuclear power plant radioactive waste to irradiate coal prior to conventional desulfurization procedures increases total extraction of sulfur.

  5. Process of desulfurization

    SciTech Connect

    Colley, J.D.

    1989-10-24

    This patent describes an improvement in a process for the desulfurization of flue gas utilizing limestone as absorbent in a double loop system, wherein the flue gas is introduced into a quenching zone for contact with a first slurry of the limestone, and thereafter passes to an absorbing zone for further contact with a second slurry of the limestone. The second slurry being supplied from a mixing zone into which water and limestone are charged. The first slurry being supplied from the solids rich stream from a solid-liquid separator which is supplied from the mixing zone, and wherein air is introduced into the quenching zone to convert the calcium sulfite present therein to gypsum. The improvement comprises supplying air to the mixing zone to convert calcium sulfite therein to large gypsum crystals which are preferentially separated into the first slurry.

  6. Enzymatic desulfurization of coal

    SciTech Connect

    Boyer, Y.N.; Crooker, S.C.; Kitchell, J.P.; Nochur, S.V. ); Marquis, J.K. . School of Medicine)

    1989-11-07

    Our experimental approach focuses on the use of enzymes which catalyze the addition of oxygen to organic compounds. In tailoring the application of these enzymes to coal processing, we are particularly interested in ensuring that oxidation occurs at sulfur and not at carbon-carbon bonds. Previous studies with DBT have shown that the reaction most frequently observed in microbial oxidative pathways is one in which DBT is oxidized at ring carbons. These reactions, as we have said, are accompanied by a considerable decrease in the energy content of the compound. In addition, microbial pathways have been identified in which the sulfur atom is sequentially oxidized to sulfoxide, to sulfone, to sulfonate, and finally to sulfuric acid. In this case, the fuel value of the desulfurized compounds is largely retained. We are evaluating the potential of commercially available enzymes to selectively catalyze oxidation at sulfur.

  7. Enzymatic desulfurization of coal

    SciTech Connect

    Boyer, Y.N.; Crooker, S.C.; Kitchell, J.P.; Nochur, S.V.

    1990-03-23

    Our experimental approach focuses on the use of enzymes which catalyze the addition of oxygen to organic compounds. In tailoring the application of these enzymes to coal processing, we are particularly interested in ensuring that oxidation occurs at sulfur and not at carbon-carbon bonds. Previous studies with DBT have shown that the reaction most frequently observed in microbial oxidative pathways is one in which DBT is oxidized at ring carbons. These reactions, as we have said, are accompanied by a considerable decrease in the energy content of the compound. In addition, microbial pathways have been identified in which the sulfur atom is sequentially oxidized to sulfoxide, to sulfone, to sulfonate, and finally to sulfuric acid. In this case, the fuel value of the desulfurized compounds is largely retained. We are evaluating the potential of commercially available enzymes to perform this function.

  8. Desulfurization of hydrocarbons

    SciTech Connect

    Eberly, P.E. Jr.

    1986-06-03

    A process is described for reforming a sulfur-containing naphtha feed, wherein is included in combination, a hydrofiner which contains a metal catalyst, the metallic component of which is selected from Group VIB and Group VIII, with which the sulfur-containing naphtha feed is contacted with hydrogen, at reaction conditions inclusive of temperatures ranging from about 400/sup 0/F to about 850/sup 0/F to remove sulfur and provide a product naphtha which contains from about 5 wppm to about 50 wppm, and higher, sulfur, a guard chamber filled with a sorbent into which the partially desulfurized hydrofined naphtha is injected to flow therethrough to effect further removal of sulfur, and a reforming unit which contains a plurality of sulfur sensitive catalyst-containing on-stream reactors connected in series, the naphtha feed to which flows in sequence from one reactor of the series of another to contact the catalyst contained therein at reforming conditions, the improvement comprising maintaining within the guard chamber a sorbent comprised of nickel in concentration ranging from about 10 percent to about 70 percent, calculated as metallic nickel based on the total weight of the sorbent, iron in concentration ranging from about 1 percent to about 15 percent, calculated as metallic iron based on the total weight of the sorbent, and a porous, refractory inorganic oxide, at temperatures ranging above about 350/sup 0/F, to produce a reformer feedstock containing no more than about 2 wppm sulfur.

  9. Desulfurization apparatus and method

    SciTech Connect

    Rong, Charles; Jiang, Rongzhong; Chu, Deryn

    2013-06-18

    A method and system for desulfurization comprising first and second metal oxides; a walled enclosure having an inlet and an exhaust for the passage of gas to be treated; the first and second metal oxide being combinable with hydrogen sulfide to produce a reaction comprising a sulfide and water; the first metal oxide forming a first layer and the second metal oxide forming a second layer within the walled surroundings; the first and second layers being positioned so the first layer removes the bulk amount of the hydrogen sulfide from the treated gas prior to passage through the second layer, and the second layer removes substantially all of the remaining hydrogen sulfide from the treated gas; the first metal oxide producing a stoichiometrical capacity in excess of 500 mg sulfur/gram; the second metal oxide reacts with the hydrogen sulfide more favorably but has a stoichometrical capacity which is less than the first reactant; whereby the optimal amount by weight of the first and second metal oxides is achieved by utilizing two to three units by weight of the first metal oxide for every unit of the second metal oxide.

  10. Desulfurization from Bauxite Water Slurry (BWS) Electrolysis

    NASA Astrophysics Data System (ADS)

    Gong, Xuzhong; Ge, Lan; Wang, Zhi; Zhuang, Siyuan; Wang, Yuhua; Ren, Lihui; Wang, Mingyong

    2016-02-01

    Feasibility of high-sulfur bauxite electrolysis desulfurization was examined using the electrochemical characterization, XRD, DTA, and FTIR. The cyclic voltammetry curves indicated that bauxite water slurry (BWS) electrolysis in NaOH system was controlled by diffusion. Additionally, the desulfurization effect of NaCl as the electrolyte was significantly better than that of NaOH as an electrolyte. As the stirring rate increased, the desulfurization ratio in NaCl system was not increased obviously, while the desulfurization ratio in NaOH system increased significantly, indicating further that electrolysis desulfurization in NaOH solution was controlled by diffusion. According to XRD, DTA, and FTIR analysis, the characteristic peaks of sulfur-containing phase in bauxite after electrolysis weakened or disappeared, indicating that the pyrite in bauxite was removed from electrolysis. Finally, the electrolytic desulfurization technology of bauxite was proposed based on the characteristics of BWS electrolysis.

  11. Coal desulfurization by aqueous chlorination

    NASA Technical Reports Server (NTRS)

    Kalvinskas, J. J.; Vasilakos, N.; Corcoran, W. H.; Grohmann, K.; Rohatgi, N. K. (Inventor)

    1982-01-01

    A method of desulfurizing coal is described in which chlorine gas is bubbled through an aqueous slurry of coal at low temperature below 130 degrees C., and at ambient pressure. Chlorinolysis converts both inorganic and organic sulfur components of coal into water soluble compounds which enter the aqueous suspending media. The media is separated after chlorinolysis and the coal dechlorinated at a temperature of from 300 C to 500 C to form a non-caking, low-sulfur coal product.

  12. Low temperature aqueous desulfurization of coal

    DOEpatents

    Slegeir, W.A.; Healy, F.E.; Sapienza, R.S.

    1985-04-18

    This invention describes a chemical process for desulfurizing coal, especially adaptable to the treatment of coal-water slurries, at temperatures as low as ambient, comprising treating the coal with aqueous titanous chloride whereby hydrogen sulfide is liberated and the desulfurized coal is separated with the conversion of titanous chloride to titanium oxides.

  13. Low temperature aqueous desulfurization of coal

    DOEpatents

    Slegeir, William A.; Healy, Francis E.; Sapienza, Richard S.

    1985-01-01

    This invention describes a chemical process for desulfurizing coal, especially adaptable to the treatment of coal-water slurries, at temperatures as low as ambient, comprising treating the coal with aqueous titanous chloride whereby hydrogen sulfide is liberated and the desulfurized coal is separated with the conversion of titanous chloride to titanium oxides.

  14. Crosstalk between the HpArsRS two-component system and HpNikR is necessary for maximal activation of urease transcription

    PubMed Central

    Carpenter, Beth M.; West, Abby L.; Gancz, Hanan; Servetas, Stephanie L.; Pich, Oscar Q.; Gilbreath, Jeremy J.; Hallinger, Daniel R.; Forsyth, Mark H.; Merrell, D. Scott; Michel, Sarah L. J.

    2015-01-01

    Helicobacter pylori NikR (HpNikR) is a nickel dependent transcription factor that directly regulates a number of genes in this important gastric pathogen. One key gene that is regulated by HpNikR is ureA, which encodes for the urease enzyme. In vitro DNA binding studies of HpNikR with the ureA promoter (PureA) previously identified a recognition site that is required for high affinity protein/DNA binding. As a means to determine the in vivo significance of this recognition site and to identify the key DNA sequence determinants required for ureA transcription, herein, we have translated these in vitro results to analysis directly within H. pylori. Using a series of GFP reporter constructs in which the PureA DNA target was altered, in combination with mutant H. pylori strains deficient in key regulatory proteins, we confirmed the importance of the previously identified HpNikR recognition sequence for HpNikR-dependent ureA transcription. Moreover, we identified a second factor, the HpArsRS two-component system that was required for maximum transcription of ureA. While HpArsRS is known to regulate ureA in response to acid shock, it was previously thought to function independently of HpNikR and to have no role at neutral pH. However, our qPCR analysis of ureA expression in wildtype, ΔnikR and ΔarsS single mutants as well as a ΔarsS/nikR double mutant strain background showed reduced basal level expression of ureA when arsS was absent. Additionally, we determined that both HpNikR and HpArsRS were necessary for maximal expression of ureA under nickel, low pH and combined nickel and low pH stresses. In vitro studies of HpArsR-P with the PureA DNA target using florescence anisotropy confirmed a direct protein/DNA binding interaction. Together, these data support a model in which HpArsRS and HpNikR cooperatively interact to regulate ureA transcription under various environmental conditions. This is the first time that direct “cross-talk” between HpArsRS and HpNikR at

  15. Crosstalk between the HpArsRS two-component system and HpNikR is necessary for maximal activation of urease transcription.

    PubMed

    Carpenter, Beth M; West, Abby L; Gancz, Hanan; Servetas, Stephanie L; Pich, Oscar Q; Gilbreath, Jeremy J; Hallinger, Daniel R; Forsyth, Mark H; Merrell, D Scott; Michel, Sarah L J

    2015-01-01

    Helicobacter pylori NikR (HpNikR) is a nickel dependent transcription factor that directly regulates a number of genes in this important gastric pathogen. One key gene that is regulated by HpNikR is ureA, which encodes for the urease enzyme. In vitro DNA binding studies of HpNikR with the ureA promoter (PureA ) previously identified a recognition site that is required for high affinity protein/DNA binding. As a means to determine the in vivo significance of this recognition site and to identify the key DNA sequence determinants required for ureA transcription, herein, we have translated these in vitro results to analysis directly within H. pylori. Using a series of GFP reporter constructs in which the PureA DNA target was altered, in combination with mutant H. pylori strains deficient in key regulatory proteins, we confirmed the importance of the previously identified HpNikR recognition sequence for HpNikR-dependent ureA transcription. Moreover, we identified a second factor, the HpArsRS two-component system that was required for maximum transcription of ureA. While HpArsRS is known to regulate ureA in response to acid shock, it was previously thought to function independently of HpNikR and to have no role at neutral pH. However, our qPCR analysis of ureA expression in wildtype, ΔnikR and ΔarsS single mutants as well as a ΔarsS/nikR double mutant strain background showed reduced basal level expression of ureA when arsS was absent. Additionally, we determined that both HpNikR and HpArsRS were necessary for maximal expression of ureA under nickel, low pH and combined nickel and low pH stresses. In vitro studies of HpArsR-P with the PureA DNA target using florescence anisotropy confirmed a direct protein/DNA binding interaction. Together, these data support a model in which HpArsRS and HpNikR cooperatively interact to regulate ureA transcription under various environmental conditions. This is the first time that direct "cross-talk" between HpArsRS and HpNikR at

  16. ADVANCED SULFUR CONTROL CONCEPTS FOR HOT GAS DESULFURIZATION TECHNOLOGY

    SciTech Connect

    1998-09-30

    The objective of this project is to develop a hot-gas desulfurization process scheme for control of H2S in HTHP coal gas that can be more simply and economically integrated with known regenerable sorbents in DOE/METC-sponsored work than current leading hot-gas desulfurization technologies. In addition to being more economical, the process scheme to be developed must yield an elemental sulfur byproduct. The Direct Sulfur Recovery Process (DSRP), a leading process for producing an elemental sulfur byproduct in hot-gas desulfurization systems, incurs a coal gas use penalty, because coal gas is required to reduce the SO2 in regeneration off-gas to elemental sulfur. Alternative regeneration schemes, which avoid coal gas use and produce elemental sulfur, will be evaluated. These include (i) regeneration of sulfided sorbent using SO2 ; (ii) partial oxidation of sulfided sorbent in an O2 starved environment; and (iii) regeneration of sulfided sorbent using steam to produce H2S followed by direct oxidation of H2S to elemental sulfur. Known regenerable sorbents will be modified to improve the feasibility of the above alternative regeneration approaches. Performance characteristics of the modified sorbents and processes will be obtained through lab- and bench-scale testing. Technical and economic evaluation of the most promising processes concept(s) will be carried out.

  17. Mass Transfer Model of Desulfurization in the Electroslag Remelting Process

    NASA Astrophysics Data System (ADS)

    Hou, Dong; Jiang, Zhou-Hua; Dong, Yan-Wu; Li, Yang; Gong, Wei; Liu, Fu-Bin

    2017-02-01

    Experimental and theoretical studies have been carried out to investigate the effects of the slag on desulfurization during the electroslag remelting (ESR) process with a focus of developing a mass transfer model to understand the mechanism of desulfurization. Stainless steel 1Cr21Ni5Ti was used as the electrode and remelted with two different kinds of slags using a 50-kg ESR furnace. The contents of sulfur along the axial direction of product ingots were analyzed. It was found that the sulfur content of 350 ppm in the electrode is reduced to 71 to 95 ppm in the ingot by remelting with the slag containing 5 wt pct of CaO, and lowered more to 47 to 59 ppm with another slag having 20 wt pct CaO. On the basis of the penetration and film theories, the theoretical model developed in this work well elucidates the kinetics of desulfurization revealing the mechanism of sulfur transfer during the ESR process. The calculation results obtained from the model agree well with the experimental results. The model indicates that when sulfur content in electrode is given, there is a corresponding minimum value of sulfur content in the ingot due to the kinetics limit. This lowest sulfur content cannot be further reduced even with increasing L S (sulfur distribution coefficient between metal and slag phases) or decreasing sulfur content in the slag. Constant addition of extra amount of CaO to the molten slag with the increase of sulfur content in the slag during the remelting process can improve the macrosegregation of sulfur distributed along the axial direction of ESR ingots. Since the rate-determining steps of the sulfur mass transfer lie in the metal phase, adding calcium as deoxidizer can change mass transfer of sulfur and thus promote desulfurization further during the ESR process.

  18. Human origin recognition complex is essential for HP1 binding to chromatin and heterochromatin organization

    PubMed Central

    Prasanth, Supriya G.; Shen, Zhen; Prasanth, Kannanganattu V.; Stillman, Bruce

    2010-01-01

    The origin recognition complex (ORC) is a DNA replication initiator protein also known to be involved in diverse cellular functions including gene silencing, sister chromatid cohesion, telomere biology, heterochromatin localization, centromere and centrosome activity, and cytokinesis. We show that, in human cells, multiple ORC subunits associate with hetereochromatin protein 1 (HP1) α- and HP1β-containing heterochromatic foci. Fluorescent bleaching studies indicate that multiple subcomplexes of ORC exist at heterochromatin, with Orc1 stably associating with heterochromatin in G1 phase, whereas other ORC subunits have transient interactions throughout the cell-division cycle. Both Orc1 and Orc3 directly bind to HP1α, and two domains of Orc3, a coiled-coil domain and a mod-interacting region domain, can independently bind to HP1α; however, both are essential for in vivo localization of Orc3 to heterochromatic foci. Direct binding of both Orc1 and Orc3 to HP1 suggests that, after the degradation of Orc1 at the G1/S boundary, Orc3 facilitates assembly of ORC/HP1 proteins to chromatin. Although depletion of Orc2 and Orc3 subunits by siRNA caused loss of HP1α association to heterochromatin, loss of Orc1 and Orc5 caused aberrant HP1α distribution only to pericentric heterochromatin-surrounding nucleoli. Depletion of HP1α from human cells also shows loss of Orc2 binding to heterochromatin, suggesting that ORC and HP1 proteins are mutually required for each other to bind to heterochromatin. Similar to HP1α-depleted cells, Orc2 and Orc3 siRNA-treated cells also show loss of compaction at satellite repeats, suggesting that ORC together with HP1 proteins may be involved in organizing higher-order chromatin structure and centromere function. PMID:20689044

  19. Two-stage coal gasification and desulfurization apparatus

    DOEpatents

    Bissett, Larry A.; Strickland, Larry D.

    1991-01-01

    The present invention is directed to a system which effectively integrates a two-stage, fixed-bed coal gasification arrangement with hot fuel gas desulfurization of a first stream of fuel gas from a lower stage of the two-stage gasifier and the removal of sulfur from the sulfur sorbent regeneration gas utilized in the fuel-gas desulfurization process by burning a second stream of fuel gas from the upper stage of the gasifier in a combustion device in the presence of calcium-containing material. The second stream of fuel gas is taken from above the fixed bed in the coal gasifier and is laden with ammonia, tar and sulfur values. This second stream of fuel gas is burned in the presence of excess air to provide heat energy sufficient to effect a calcium-sulfur compound forming reaction between the calcium-containing material and sulfur values carried by the regeneration gas and the second stream of fuel gas. Any ammonia values present in the fuel gas are decomposed during the combustion of the fuel gas in the combustion chamber. The substantially sulfur-free products of combustion may then be combined with the desulfurized fuel gas for providing a combustible fluid utilized for driving a prime mover.

  20. Protein designs in HP models

    NASA Astrophysics Data System (ADS)

    Gupta, Arvind; Khodabakhshi, Alireza Hadj; Maňuch, Ján; Rafiey, Arash; Stacho, Ladislav

    2009-07-01

    The inverse protein folding problem is that of designing an amino acid sequence which folds into a prescribed shape. This problem arises in drug design where a particular structure is necessary to ensure proper protein-protein interactions and could have applications in nanotechnology. A major challenge in designing proteins with native folds that attain a specific shape is to avoid proteins that have multiple native folds (unstable proteins). In this technical note we present our results on protein designs in the variant of Hydrophobic-Polar (HP) model introduced by Dill [6] on 2D square lattice. The HP model distinguishes only polar and hydrophobic monomers and only counts the number of hydrophobic contacts in the energy function. To achieve better stability of our designs we use the Hydrophobic-Polar-Cysteine (HPC) model which distinguishes the third type of monomers called "cysteines" and incorporates also the disulfid bridges (SS-bridges) into the energy function. We present stable designs in 2D square lattice and 3D hexagonal prism lattice in the HPC model.

  1. DIGLIB for HP-1000 computers

    SciTech Connect

    Treadway, T.R.

    1983-11-01

    DIGLIB (Device Independent Graphic LIBrary), originally developed by Hal R. Brand for DEC computers, has been modified for use by HP 1000 computers running under RTE. DIGLIB consists of a small but functionally complete set of FORTRAN-callable library subroutines for creating arbitrary views of two-dimensional objects and for supporting interaction between the graphic application program and its user. Graphic presentation is oriented towards interactive graphic display devices (such as the HP 2648A or Tektronix 4025) and line-drawing plotters (like the CalComp pen plotters). In addition, a high density Versatec V-80 or 1200 electrostatic printer/plotter interface is available. DIGLIB makes the application program independent of the specific graphic hardware devices, thereby presenting a uniform programmer interface to the graphics library, requiring few modifications (typically one) to the application program in order to accommodate a different graphics configuration. A device-independent subroutine library provides a high level of program portability, allowing support of a variety of different display controllers and operating environments.

  2. Flue gas desulfurization

    DOEpatents

    Im, K.H.; Ahluwalia, R.K.

    1984-05-01

    The invention involves a combustion process in which combustion gas containing sulfur oxide is directed past a series of heat exchangers to a stack and in which a sodium compound is added to the combustion gas in a temparature zone of above about 1400 K to form Na/sub 2/SO/sub 4/. Preferably, the temperature is above about 1800 K and the sodium compound is present as a vapor to provide a gas-gas reaction to form Na/sub 2/SO/sub 4/ as a liquid. Since liquid Na/sub 2/SO/sub 4/ may cause fouling of heat exchanger surfaces downstream from the combustion zone, the process advantageously includes the step of injecting a cooling gas downstream of the injection of the sodium compound yet upstream of one or more heat exchangers to cool the combustion gas to below about 1150 K and form solid Na/sub 2/SO/sub 4/. The cooling gas is preferably a portion of the combustion gas downstream which may be recycled for cooling. It is further advantageous to utilize an electrostatic precipitator downstream of the heat exchangers to recover the Na/sub 2/SO/sub 4/. It is also advantageous in the process to remove a portion of the combustion gas cleaned in the electrostatic precipitator and recycle that portion upstream to use as the cooling gas. 3 figures.

  3. Affinity, stoichiometry and cooperativity of heterochromatin protein 1 (HP1) binding to nucleosomal arrays

    NASA Astrophysics Data System (ADS)

    Teif, Vladimir B.; Kepper, Nick; Yserentant, Klaus; Wedemann, Gero; Rippe, Karsten

    2015-02-01

    Heterochromatin protein 1 (HP1) participates in establishing and maintaining heterochromatin via its histone-modification-dependent chromatin interactions. In recent papers HP1 binding to nucleosomal arrays was measured in vitro and interpreted in terms of nearest-neighbour cooperative binding. This mode of chromatin interaction could lead to the spreading of HP1 along the nucleosome chain. Here, we reanalysed previous data by representing the nucleosome chain as a 1D binding lattice and showed how the experimental HP1 binding isotherms can be explained by a simpler model without cooperative interactions between neighboring HP1 dimers. Based on these calculations and spatial models of dinucleosomes and nucleosome chains, we propose that binding stoichiometry depends on the nucleosome repeat length (NRL) rather than protein interactions between HP1 dimers. According to our calculations, more open nucleosome arrays with long DNA linkers are characterized by a larger number of binding sites in comparison to chains with a short NRL. Furthermore, we demonstrate by Monte Carlo simulations that the NRL dependent folding of the nucleosome chain can induce allosteric changes of HP1 binding sites. Thus, HP1 chromatin interactions can be modulated by the change of binding stoichiometry and the type of binding to condensed (methylated) and non-condensed (unmethylated) nucleosome arrays in the absence of direct interactions between HP1 dimers.

  4. Use of glass fiber-reinforced plastic as an absorber in limestone wet flue gas desulfurization.

    PubMed

    Lin, Haibo

    2008-10-01

    The choice of materials for the spraying and oxidation of pipes directly affect the operation in limestone wet flue gas desulfurization (FGD). There is reason to consider using glass fiber-reinforced plastic (FRP) instead of expensive high nickel alloy for the spraying and oxidation of pipes.

  5. Sequence and molecular characterization of a DNA region encoding the dibenzothiophene desulfurization operon of Rhodococcus sp. strain IGTS8.

    PubMed

    Piddington, C S; Kovacevich, B R; Rambosek, J

    1995-02-01

    Dibenzothiophene (DBT), a model compound for sulfur-containing organic molecules found in fossil fuels, can be desulfurized to 2-hydroxybiphenyl (2-HBP) by Rhodococcus sp. strain IGTS8. Complementation of a desulfurization (dsz) mutant provided the genes from Rhodococcus sp. strain IGTS8 responsible for desulfurization. A 6.7-kb TaqI fragment cloned in Escherichia coli-Rhodococcus shuttle vector pRR-6 was found to both complement this mutation and confer desulfurization to Rhodococcus fascians, which normally is not able to desulfurize DBT. Expression of this fragment in E. coli also conferred the ability to desulfurize DBT. A molecular analysis of the cloned fragment revealed a single operon containing three open reading frames involved in the conversion of DBT to 2-HBP. The three genes were designated dszA, dszB, and dszC. Neither the nucleotide sequences nor the deduced amino acid sequences of the enzymes exhibited significant similarity to sequences obtained from the GenBank, EMBL, and Swiss-Prot databases, indicating that these enzymes are novel enzymes. Subclone analyses revealed that the gene product of dszC converts DBT directly to DBT-sulfone and that the gene products of dszA and dszB act in concert to convert DBT-sulfone to 2-HBP.

  6. Method for desulfurization of coal

    DOEpatents

    Kelland, David R.

    1987-01-01

    A process and apparatus for desulfurizing coal which removes sulfur in the inorganic and organic form by preferentially heating the inorganic iron sulfides in coal in a flowing gas to convert some of the inorganic iron sulfides from a pyrite form FeS.sub.2 to a troilite FeS form or a pyrrhotite form Fe.sub.1-x S and release some of the sulfur as a gaseous compound. The troilite and pyrrhotite forms are convenient catalyst for removing the organic sulfur in the next step, which is to react the coal with chemical agents such as alcohol, thus removing the organic sulfur as a liquid or a gas such as H.sub.2 S. The remaining inorganic sulfur is left in the predominantly higher magnetic form of pyrrhotite and is then removed by magnetic separation techniques. Optionally, an organic flocculant may be added after the organic sulfur has been removed and before magnetic separation. The flocculant attaches non-pyrite minerals with the pyrrhotite for removal by magnetic separation to reduce the ash-forming contents.

  7. Method for desulfurization of coal

    DOEpatents

    Kelland, D.R.

    1987-07-07

    A process and apparatus are disclosed for desulfurizing coal which removes sulfur in the inorganic and organic form by preferentially heating the inorganic iron sulfides in coal in a flowing gas to convert some of the inorganic iron sulfides from a pyrite form FeS[sub 2] to a troilite FeS form or a pyrrhotite form Fe[sub 1[minus]x]S and release some of the sulfur as a gaseous compound. The troilite and pyrrhotite forms are convenient catalyst for removing the organic sulfur in the next step, which is to react the coal with chemical agents such as alcohol, thus removing the organic sulfur as a liquid or a gas such as H[sub 2]S. The remaining inorganic sulfur is left in the predominantly higher magnetic form of pyrrhotite and is then removed by magnetic separation techniques. Optionally, an organic flocculant may be added after the organic sulfur has been removed and before magnetic separation. The flocculant attaches non-pyrite minerals with the pyrrhotite for removal by magnetic separation to reduce the ash-forming contents. 2 figs.

  8. Process for desulfurizing an exhaust gas

    SciTech Connect

    Shinoda, N.; Okino, S.; Oshima, M.; Shigeta, S.; Tatani, A.; Ukawa, N.

    1983-12-13

    A process is disclosed for desulfurizing an exhaust gas which comprises desulfurizing an exhaust gas containing SO/sub 2/ by bringing it into contact with a slurry containing calcium compounds and aluminum compounds, characterized in that the concentration of the dissolved aluminum ion in said slurry is detected and a manganese compound is supplied into said slurry in such a manner that the ratio of the concentration of manganese (including both solid and liquid) to said concentration of the dissolved aluminum ion may be maintained in a molar ratio of less than 1 in said slurry.

  9. Operation of the HP2250 with the HP9000 series 200 using PASCAL 3.0

    NASA Technical Reports Server (NTRS)

    Perry, John; Stroud, C. W.

    1986-01-01

    A computer program has been written to provide an interface between the HP Series 200 desktop computers, operating under HP Standard Pascal 3.0, and the HP2250 Data Acquisition and Control System. Pascal 3.0 for the HP9000 desktop computer gives a number of procedures for handling bus communication at various levels. It is necessary, however, to reach the lowest possible level in Pascal to handle the bus protocols required by the HP2250. This makes programming extremely complex since these protocols are not documented. The program described solves those problems and allows the user to immediately program, simply and efficiently, any measurement and control language (MCL/50) application with a few procedure calls. The complete set of procedures is available on a 5 1/4 inch diskette from Cosmic. Included in this group of procedures is an Exerciser which allows the user to exercise his HP2250 interactively. The exerciser operates in a fashion similar to the Series 200 operating system programs, but is adapted to the requirements of the HP2250. The programs on the diskette and the user's manual assume the user is acquainted with both the MCL/50 programming language and HP Standard Pascal 3.0 for the HP series 200 desktop computers.

  10. Desulfurization, demetalation and denitrogenation of coal

    SciTech Connect

    Farcasiu, M.; Mitchell, T.O.; Whitehurst, D.D.

    1981-12-01

    The specification discloses a desulfurization, demetalation and denitrogenation process for coal and coal liquid charge stocks. The process comprises contacting the charge stock in the absence of externally added hydrogen with a hydrogen donor solvent in the presence of a catalytic amount of naturally occurring porous metal ores such as manganese nodules, bog iron, bog manganese, nickel laterites, bauxite or spent bauxite.

  11. Recombinant DNA encoding a desulfurization biocatalyst

    DOEpatents

    Rambosek, J.; Piddington, C.S.; Kovacevich, B.R.; Young, K.D.; Denome, S.A.

    1994-10-18

    This invention relates to a recombinant DNA molecule containing a gene or genes which encode a biocatalyst capable of desulfurizing a fossil fuel which contains organic sulfur molecules. For example, the present invention encompasses a recombinant DNA molecule containing a gene or genes of a strain of Rhodococcus rhodochrous. 13 figs.

  12. Recombinant DNA encoding a desulfurization biocatalyst

    DOEpatents

    Rambosek, John; Piddington, Chris S.; Kovacevich, Brian R.; Young, Kevin D.; Denome, Sylvia A.

    1994-01-01

    This invention relates to a recombinant DNA molecule containing a gene or genes which encode a biocatalyst capable of desulfurizing a fossil fuel which contains organic sulfur molecules. For example, the present invention encompasses a recombinant DNA molecule containing a gene or genes of a strain of Rhodococcus rhodochrous.

  13. Low-Cost Aqueous Coal Desulfurization

    NASA Technical Reports Server (NTRS)

    Kalvinskas, J. J.; Vasilakos, N.; Corcoran, W. H.; Grohmann, K.; Rohatgi, N. K.

    1982-01-01

    Water-based process for desulfurizing coal not only eliminates need for costly organic solvent but removes sulfur more effectively than an earlier solvent-based process. New process could provide low-cost commercial method for converting high-sulfur coal into environmentally acceptable fuel.

  14. [Performance of desulfurizing absorbent of roasted navajoite].

    PubMed

    Chen, Fang; Yang, Chun-ping; Gan, Hai-ming; Wu, Ting; Chen, Hai-lin; Chen, Hong; Xu, Ke-hui; Xie, Geng-xin

    2010-04-01

    An innovative flue gas desulfurization (FGD) coupling process was proposed in this study to overcome the problems in wet-type limestone/lime processes which include fouling, clogging, and difficulty of selling the by-products and the problems in traditional process for vanadium extraction from navajoite ore such as excessive consumption of sulfuric acid and emissions of pollutants. The performance of a jet bubbling reactor (JBR) at pilot-scale was evaluated using navajoite ore produced in the process of extracting vanadium pentoxide as desulfurization absorbent. Results showed that navajoite ore slurry achieved better desulfurization performance than limestone slurry. When the inlet flue gas pressure drop was 3.0 kPa, the gas flow was about 2350 m3 x h(-1) and the pH of the navajoite ore slurry was higher than 4.5, the desulfurization efficiency was stable about 90%. The SO2 removal efficiency appeared to increase along with the increasing of absorbent cycle-index. The efficiency of the second circulation was improved 3.5% compared to the first circulation. After an operating duration of 40 minutes, the leaching rate of vanadium pentoxide was about 20%, and reached 60% when the by-products were leached with 5% dilute sulfuric acid for 10 hours. The by-product from this process not only could be used to produce vanadium pentoxide which is a valuable industrial product, but also could significantly overcome the pollution problem existing in the traditional refining process of vanadium pentoxide when navajoite ore is used as the feed material. This FGD process using roasted navajoite slurry as absorbent is environmental sound and cost-effective, and shows the potential for application in the field of flue gas desulfurization as well as hydrometallurgy.

  15. ADVANCED SULFUR CONTROL CONCEPTS FOR HOT-GAS DESULFURIZATION TECHNOLOGY

    SciTech Connect

    A. LOPEZ ORTIZ; D.P. HARRISON; F.R. GROVES; J.D. WHITE; S. ZHANG; W.-N. HUANG; Y. ZENG

    1998-10-31

    This research project examined the feasibility of a second generation high-temperature coal gas desulfurization process in which elemental sulfur is produced directly during the sorbent regeneration phase. Two concepts were evaluated experimentally. In the first, FeS was regenerated in a H2O-O2 mixture. Large fractions of the sulfur were liberated in elemental form when the H2O-O2 ratio was large. However, the mole percent of elemental sulfur in the product was always quite small (<<1%) and a process based on this concept was judged to be impractical because of the low temperature and high energy requirements associated with condensing the sulfur. The second concept involved desulfurization using CeO2 and regeneration of the sulfided sorbent, Ce2O2S, using SO2 to produce elemental sulfur directly. No significant side reactions were observed and the reaction was found to be quite rapid over the temperature range of 500°C to 700°C. Elemental sulfur concentrations (as S2) as large as 20 mol% were produced. Limitations associated with the cerium sorbent process are concentrated in the desulfurization phase. High temperature and highly reducing coal gas such as produced in the Shell gasification process are required if high sulfur removal efficiencies are to be achieved. For example, the equilibrium H2S concentration at 800°C from a Shell gas in contact with CeO2 is about 300 ppmv, well above the allowable IGCC specification. In this case, a two-stage desulfurization process using CeO2 for bulk H2S removal following by a zinc sorbent polishing step would be required. Under appropriate conditions, however, CeO2 can be reduced to non-stoichiometric CeOn (n<2) which has significantly greater affinity for H2S. Pre-breakthrough H2S concentrations in the range of 1 ppmv to 5 ppmv were measured in sulfidation tests using CeOn at 700°C in highly reducing gases, as measured by equilibrium O2 concentration, comparable to the Shell gas. Good sorbent durability was indicated in

  16. Hydrogen Peroxide (HP) Potential for Space Applications

    NASA Astrophysics Data System (ADS)

    Grafwallner, F.

    2004-10-01

    Low toxicity or "green" propellants are now under study by organizations around the world. Especially ultra high concentrated hydrogen peroxide (HP) may be a significant step toward less toxic, storable und safer operation of upper stages and spacecrafts. HP can be used as a monopropellant, when catalytically decomposed or as a bipropellant constituting the propellant combination`s oxidizer. Serving as a monopropellant, catalytic decomposition will result in exhaust of superheated steam and oxygen which can be used to drive gas turbines and feed life support systems or provide thrust as a monopropellant, provide the oxidizer, or function as an igniter for bipropellant engines. HP can be used in fuel cells to produce electrical power, heat and water.

  17. Hot Gas Desulfurization Using Transport Reactors

    SciTech Connect

    Moorehead, E.L.

    1996-12-31

    Sierra Pacific Power Company is building a 100 MW, IGCC power plant based on KRW fluid bed gasifier technology that utilizes transport reactors for hot gas desulfurization and sorbent regeneration. Use of a transport absorber avoids the need for pre-filtration of dust-laden gasifier effluent, while a transport regenerator allows for the use of 100% air without the need for heat exchange equipment. Selection of transport reactors for hot gas desulfurization using a proprietary sorbent, based on testing performed in a transport reactor test unit (TRTU) at the M. W. Kellogg Technology Development Center and in a fixed bed reactor at Morgantown Energy Technology Center (METC), is outlined. The results obtained in these two test facilities and reasons for selecting transport reactors for the IGCC power plant in preference to either fixed bed or fluidized bed reactors are discussed. This paper reviews the evolution of the hot gas desulfurization system designs and includes selected results on H{sub 2}S absorption and regeneration of sulfided sorbent over several absorption/regeneration cycles conducted in the TRTU and the METC fixed bed reactor. The original design for the Sierra Pacific Project was based on fixed bed reactors with zinc ferrite as the sorbent. Owing to the high steam requirements of this sorbent, zinc titanate was selected and tested in a fixed bed reactor and was found unacceptable due to loss of strength on cyclic absorption/regeneration operation. Another sorbent evaluated was Z-Sorb{reg_sign}, a proprietary sorbent developed by Phillips Petroleum Company, was found to have excellent sulfur capacity, structural strength and regenerability. Steam was found unsuitable as fixed bed regenerator diluent, this results in a requirement for a large amount of inert gas, whereas a transport regenerator requires no diluent. The final Sierra design features transport reactors for both desulfurization and regeneration steps using neat air. 3 refs., 3 figs., 2 tabs.

  18. Desulfurizing Coal With an Alkali Treatment

    NASA Technical Reports Server (NTRS)

    Ravindram, M.; Kalvinskas, J. J.

    1987-01-01

    Experimental coal-desulfurization process uses alkalies and steam in fluidized-bed reactor. With highly volatile, high-sulfur bituminous coal, process removed 98 percent of pyritic sulfur and 47 percent of organic sulfur. Used in coal liquefaction and in production of clean solid fuels and synthetic liquid fuels. Nitrogen or steam flows through bed of coal in reactor. Alkalies react with sulfur, removing it from coal. Nitrogen flow fluidizes bed while heating or cooling; steam is fluidizing medium during reaction.

  19. Zirconia-silica based mesoporous desulfurization adsorbents

    NASA Astrophysics Data System (ADS)

    Palomino, Jessica M.; Tran, Dat T.; Kareh, Ana R.; Miller, Christopher A.; Gardner, Joshua M. V.; Dong, Hong; Oliver, Scott R. J.

    2015-03-01

    We report a series of mesoporous silicate sorbent materials templated by long-chain primary alkylamines that display record level of desulfurization of the jet fuel JP-8. Pure silica frameworks and those with a Si:Zr synthesis molar ratio ranging from 44:1 to 11:1 were investigated. The optimum sorbent was identified as dodecylamine-templated silica-zirconia synthesized from a gel with Si:Zr molar ratio of 15:1. With an optimized silver loading of 11 wt.%, a saturation adsorption capacity of 39.4 mgS g-1 and a silver efficiency of 1.21 molS mol Ag-1 were observed for JP-8. This sorbent displayed exceptional regenerability, maintaining 86% of its initial capacity in model fuel after solvent regeneration with diethyl ether. Low-cost, portable and reusable sorbents for the desulfurization of JP-8 jet fuel are needed to make solid oxide fuel cells (SOFCs) a reality for military power needs. SOFCs require ultra-low sulfur content fuel, which traditional desulfurization methods cannot achieve.

  20. The Orphan Response Regulator HP1021 of Helicobacter pylori Regulates Transcription of a Gene Cluster Presumably Involved in Acetone Metabolism▿ †

    PubMed Central

    Pflock, Michael; Bathon, Melanie; Schär, Jennifer; Müller, Stefanie; Mollenkopf, Hans; Meyer, Thomas F.; Beier, Dagmar

    2007-01-01

    Helicobacter pylori is a gastric pathogen for which no nonhuman reservoir is known. In accordance with the tight adaptation to its unique habitat, the human stomach, H. pylori is endowed with a very restricted repertoire of regulatory proteins. Nevertheless, the three complete two-component systems of H. pylori were shown to be involved in the regulation of important virulence traits like motility and acid resistance and in the control of metal homeostasis. HP1021 is an orphan response regulator with an atypical receiver domain whose inactivation has a considerable impact on the growth of H. pylori. Here we report the identification of HP1021-regulated genes by whole-genome transcriptional profiling. We show that the transcription of the essential housekeeping genes nifS and nifU, which are required for the assembly of Fe-S clusters, is activated by HP1021. Furthermore, we demonstrate that the expression of a gene cluster comprising open reading frames hp0690 to hp0693 and hp0695 to hp0697 which is probably involved in acetone metabolism is strongly upregulated by HP1021. Evidence is provided for a direct regulation of the hp0695-to-hp0697 operon by the binding of HP1021 to its promoter region. PMID:17220217

  1. Functional Association between Eyegone and HP1a Mediates wingless Transcriptional Repression during Development

    PubMed Central

    Salvany, Lara; Requena, David

    2012-01-01

    The eyegone (eyg) gene encodes Eyg, a transcription factor of the Pax family with multiple roles during Drosophila development. Although Eyg has been shown to act as a repressor, nothing is known about the mechanism by which it represses its target genes. Here, we show that Eyg forms a protein complex with heterochromatin protein 1a (HP1a). Both proteins bind to the same chromatin regions on polytene chromosomes and act cooperatively to suppress variegation and mediate gene silencing. In addition, Eyg binds to a wingless (wg) enhancer region, recruiting HP1a to assemble a closed, heterochromatin-like conformation that represses transcription of the wg gene. We describe here the evidence that suggests that Eyg, encoded by eyegone (eyg), represses wingless (wg) during eye development by association with HP1a. We show that Eyg forms a protein complex with HP1a and both proteins colocalize on salivary gland polytene chromosomes. Using position effect variegation (PEV) experiments, we demonstrated that eyg has a dose-dependent effect on heterochromatin gene silencing and identified a genetic interaction with HP1a in this process. We further demonstrated that HP1a binds to the same wg enhancer element as Eyg. DNase I sensitivity assays indicated that this enhancer region has a closed heterochromatin-like conformation, which becomes open in eyg mutants. In these mutants, much less HP1a binds to the wg enhancer region, as shown by ChIP experiments. Furthermore, as previously described for Eyg, a reduction in the amount of HP1a in the eye imaginal disc derepresses wg. Together, our results suggest a model in which Eyg specifically binds to the wg enhancer region, recruiting HP1a to that site. The recruitment of HP1a prevents transcription by favoring a closed, heterochromatin-like structure. Thus, for the first time, we show that HP1a plays a direct role in the repression of a developmentally regulated gene, wg, during Drosophila eye development. PMID:22547675

  2. Functional impact of Aurora A-mediated phosphorylation of HP1γ at serine 83 during cell cycle progression

    PubMed Central

    2013-01-01

    Background Previous elegant studies performed in the fission yeast Schizosaccharomyces pombe have identified a requirement for heterochromatin protein 1 (HP1) for spindle pole formation and appropriate cell division. In mammalian cells, HP1γ has been implicated in both somatic and germ cell proliferation. High levels of HP1γ protein associate with enhanced cell proliferation and oncogenesis, while its genetic inactivation results in meiotic and mitotic failure. However, the regulation of HP1γ by kinases, critical for supporting mitotic progression, remains to be fully characterized. Results We report for the first time that during mitotic cell division, HP1γ colocalizes and is phosphorylated at serine 83 (Ser83) in G2/M phase by Aurora A. Since Aurora A regulates both cell proliferation and mitotic aberrations, we evaluated the role of HP1γ in the regulation of these phenomena using siRNA-mediated knockdown, as well as phosphomimetic and nonphosphorylatable site-directed mutants. We found that genetic downregulation of HP1γ, which decreases the levels of phosphorylation of HP1γ at Ser83 (P-Ser83-HP1γ), results in mitotic aberrations that can be rescued by reintroducing wild type HP1γ, but not the nonphosphorylatable S83A-HP1γ mutant. In addition, proliferation assays showed that the phosphomimetic S83D-HP1γ increases 5-ethynyl-2´-deoxyuridine (EdU) incorporation, whereas the nonphosphorylatable S83A-HP1γ mutant abrogates this effect. Genome-wide expression profiling revealed that the effects of these mutants on mitotic functions are congruently reflected in G2/M gene expression networks in a manner that mimics the on and off states for P-Ser83-HP1γ. Conclusions This is the first description of a mitotic Aurora A-HP1γ pathway, whose integrity is necessary for the execution of proper somatic cell division, providing insight into specific types of posttranslational modifications that associate to distinct functional outcomes of this important chromatin

  3. Flue gas desulfurization gypsum agricultural network alabama (cotton)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Flue gas desulfurization gypsum (FGDG) is an excellent source of gypsum (CaSO4•2H2O) that can be beneficially used in agriculture. Research was conducted as part of the Flue Gas Desulfurization Gypsum Agricultural Network program sponsored by the Electric Power Research Institute in collaboration wi...

  4. The middle region of an HP1-binding protein, HP1-BP74, associates with linker DNA at the entry/exit site of nucleosomal DNA.

    PubMed

    Hayashihara, Kayoko; Uchiyama, Susumu; Shimamoto, Shigeru; Kobayashi, Shouhei; Tomschik, Miroslav; Wakamatsu, Hidekazu; No, Daisuke; Sugahara, Hiroki; Hori, Naoto; Noda, Masanori; Ohkubo, Tadayasu; Zlatanova, Jordanka; Matsunaga, Sachihiro; Fukui, Kiichi

    2010-02-26

    In higher eukaryotic cells, DNA molecules are present as chromatin fibers, complexes of DNA with various types of proteins; chromatin fibers are highly condensed in metaphase chromosomes during mitosis. Although the formation of the metaphase chromosome structure is essential for the equal segregation of replicated chromosomal DNA into the daughter cells, the mechanism involved in the organization of metaphase chromosomes is poorly understood. To identify proteins involved in the formation and/or maintenance of metaphase chromosomes, we examined proteins that dissociated from isolated human metaphase chromosomes by 0.4 m NaCl treatment; this treatment led to significant chromosome decondensation, but the structure retained the core histones. One of the proteins identified, HP1-BP74 (heterochromatin protein 1-binding protein 74), composed of 553 amino acid residues, was further characterized. HP1-BP74 middle region (BP74Md), composed of 178 amino acid residues (Lys(97)-Lys(274)), formed a chromatosome-like structure with reconstituted mononucleosomes and protected the linker DNA from micrococcal nuclease digestion by approximately 25 bp. The solution structure determined by NMR revealed that the globular domain (Met(153)-Thr(237)) located within BP74Md possesses a structure similar to that of the globular domain of linker histones, which underlies its nucleosome binding properties. Moreover, we confirmed that BP74Md and full-length HP1-BP74 directly binds to HP1 (heterochromatin protein 1) and identified the exact sites responsible for this interaction. Thus, we discovered that HP1-BP74 directly binds to HP1, and its middle region associates with linker DNA at the entry/exit site of nucleosomal DNA in vitro.

  5. Effect of Mutations on HP Lattice Proteins

    NASA Astrophysics Data System (ADS)

    Shi, Guangjie; Vogel, Thomas; Landau, David; Li, Ying; Wüst, Thomas

    2013-03-01

    Using Wang-Landau sampling with approriate trial moves[2], we investigate the effect of different types of mutations on lattice proteins in the HP model. While exact studies have been carried out for short HP proteins[3], the systems we investigate are of much larger size and hence not accessible for exact enumerations. Based on the estimated density of states, we systematically analyse the changes in structure and degeneracy of ground states of particular proteins and measure thermodynamic quantities like the stability of ground states and the specific heat, for example. Both, neutral mutations, which do not change the structure and stability of ground states, as well as critical mutations, which do change the thermodynamic behavior qualitatively, have been observed. Research supported by NSF

  6. HP-41 Calculates Dykstra-Parsons permeability

    SciTech Connect

    Bixler, B.

    1983-07-01

    A new program for the HP-41 programmable calculator has been written which will calculate the often used Dykstra-Parsons permeability variation factor, V. No longer must numerous individual permeability values be plotted on log probability paper as a first step in determining V. Input is simply these same permeability values selected at equal spacing along the interval in question. For most core analysis this spacing will be 1 ft. This program is labeled ''KVAR'' (for permeability variation) and is listed here, along with its bar code for those with optical wands. It requires only nine registers for program storage (since it uses HP built-in statistical functions) and eight registers for data storage. Also, it can be stored on one track of the standard two-track magnetic card. Data entry is terminated by entering ''O''. Lastly, it will run with or without a printer.

  7. Some properties of the noncommutative Hp(r ,s ) (𝒜; ℓ∞) and Hp(𝒜; ℓ1) spaces

    NASA Astrophysics Data System (ADS)

    Tulenov, Kanat

    2015-09-01

    In this paper, we introduce the noncommutative Hp(r ,s ) (𝒜; ℓ∞) and Hp (𝒜; ℓ1) spaces. Then, it is shown that both spaces are Banach spaces for r, s ≥ 2 (and resp. p ≥ 1) and the analogue of Saito's theorem for the Hp(r ,s ) (𝒜; ℓ∞) and Hp(𝒜; ℓ1) spaces are proved.

  8. Sorbent for use in hot gas desulfurization

    DOEpatents

    Gasper-Galvin, Lee D.; Atimtay, Aysel T.

    1993-01-01

    A multiple metal oxide sorbent supported on a zeolite of substantially silicon oxide is used for the desulfurization of process gas streams, such as from a coal gasifier, at temperatures in the range of about 1200.degree. to about 1600.degree. F. The sorbent is provided by a mixture of copper oxide and manganese oxide and preferably such a mixture with molybdenum oxide. The manganese oxide and the molybdenum are believed to function as promoters for the reaction of hydrogen sulfide with copper oxide. Also, the manganese oxide inhibits the volatilization of the molybdenum oxide at the higher temperatures.

  9. Flue gas desulfurization wastewater treatment primer

    SciTech Connect

    Higgins, T.E.; Sandy, A.T.; Givens, S.W.

    2009-03-15

    Purge water from a typical wet flue gas desulfurization system contains myriad chemical constituents and heavy metals whose mixture is determined by the fuel source and combustion products as well as the stack gas treatment process. A well-designed water treatment system can tolerate upstream fuel and sorbent arranged in just the right order to produce wastewater acceptable for discharge. This article presents state-of-the-art technologies for treating the waste water that is generated by wet FGD systems. 11 figs., 3 tabs.

  10. Desulfurization Sorbents for Transport-Bed Applications

    SciTech Connect

    Gupta, Raghubir P.; Turk, Brian S.; Vierheilig, Albert A.

    1997-07-01

    This project extends the prior work on the development of fluidizable zinc titanate particles using a spray-drying technique to impart high reactivity and attrition resistance. The specific objectives are: (1) To develop highly reactive and attrition-resistant zinc titanate sorbents in 40- to 150-{micro}m particle size range for transport reactor applications; (2) To transfer sorbent production technology to private sector; and (3) To provide technical support to Sierra Pacific Clean Coal Technology Demonstration plant and FETC's Hot-Gas Desulfurization Process Development Unit (PDU), both employing a transport reactor system.

  11. Advanced Hot-Gas Desulfurization Sorbents

    SciTech Connect

    Jothimurugesan, K.; Adeyiga, A.; Gangwal, S.K.

    1996-12-31

    The objective of this project is to develop advanced hot-gas desulfurization sorbents for relatively low temperature application that show stable and high sulfidation reactivity at 343 to 538 {degrees}C. A number of zinc-based formulations will be prepared and screened for testing in a fixed-bed reactor at high pressure (1 to 20 atm) and high temperatures using simulated coal-derived fuel gases. One of the superior formulations will be tested for long- term durability and chemical reactivity in the reactor. To prevent sulfation, catalyst additives will be investigated, which would promote a lower regeneration temperature.

  12. Structural basis of HP1/PXVXL motif peptide interactions and HP1 localisation to heterochromatin

    PubMed Central

    Thiru, Abarna; Nietlispach, Daniel; Mott, Helen R; Okuwaki, Mitsuru; Lyon, Debbie; Nielsen, Peter R; Hirshberg, Miriam; Verreault, Alain; Murzina, Natalia V; Laue, Ernest D

    2004-01-01

    HP1 family proteins are adaptor molecules, containing two related chromo domains that are required for chromatin packaging and gene silencing. Here we present the structure of the chromo shadow domain from mouse HP1β bound to a peptide containing a consensus PXVXL motif found in many HP1 binding partners. The shadow domain exhibits a novel mode of peptide recognition, where the peptide binds across the dimer interface, sandwiched in a β-sheet between strands from each monomer. The structure allows us to predict which other shadow domains bind similar PXVXL motif-containing peptides and provides a framework for predicting the sequence specificity of the others. We show that targeting of HP1β to heterochromatin requires shadow domain interactions with PXVXL-containing proteins in addition to chromo domain recognition of Lys-9-methylated histone H3. Interestingly, it also appears to require the simultaneous recognition of two Lys-9-methylated histone H3 molecules. This finding implies a further complexity to the histone code for regulation of chromatin structure and suggests how binding of HP1 family proteins may lead to its condensation. PMID:14765118

  13. METC hot gas desulfurization program overview

    SciTech Connect

    Cicero, D.C.

    1994-10-01

    This overview provides a frame of reference for the Morgantown Energy Technology Center`s (METC`S) on-going hot gas desulfurization research. Although there are several methods to separate contaminant gases from fuel gases, that method receiving primary development is absorption through the use of metal oxides. Research into high-temperature and high-pressure control of sulfur species includes primarily those sorbents made of mixed-metal oxides, which offer the advantages of regenerability. These are predominantly composed of zinc and are made into media that can be utilized in reactors of either fixed-bed, moving-bed, fluidized-bed, or transport configurations. Zinc Ferrite (ZnO-Fe{sub 2}O{sub 3}), Zinc Titanate (ZnO-TiO{sub 2}), Z-SORP{reg_sign}, and METC-2/METC-6 are the current mixed-metal sorbents being investigated. The METC desulfurization program is composed of three major components: bench-scale research, pilot-plant operation, and demonstration that is a portion of the Clean Coal Demonstration projects.

  14. Biocatalytic desulfurization (BDS) of petrodiesel fuels.

    PubMed

    Mohebali, Ghasemali; Ball, Andrew S

    2008-08-01

    Oil refineries are facing many challenges, including heavier crude oils, increased fuel quality standards, and a need to reduce air pollution emissions. Global society is stepping on the road to zero-sulfur fuel, with only differences in the starting point of sulfur level and rate reduction of sulfur content between different countries. Hydrodesulfurization (HDS) is the most common technology used by refineries to remove sulfur from intermediate streams. However, HDS has several disadvantages, in that it is energy intensive, costly to install and to operate, and does not work well on refractory organosulfur compounds. Recent research has therefore focused on improving HDS catalysts and processes and also on the development of alternative technologies. Among the new technologies one possible approach is biocatalytic desulfurization (BDS). The advantage of BDS is that it can be operated in conditions that require less energy and hydrogen. BDS operates at ambient temperature and pressure with high selectivity, resulting in decreased energy costs, low emission, and no generation of undesirable side products. Over the last two decades several research groups have attempted to isolate bacteria capable of efficient desulfurization of oil fractions. This review examines the developments in our knowledge of the application of bacteria in BDS processes, assesses the technical viability of this technology and examines its future challenges.

  15. Process for desulfurizing combustion exhaust gases

    SciTech Connect

    Kumagai, T.; Matsuda, S.; Mori, T.; Nishimura, T.; Nishimura, Y.

    1982-05-04

    An improved process for desulfurizing combustion exhaust gases of mainly coal containing sulfur oxides, Hf and dust containing Al is provided, which process consists of four steps; a first step of contacting the gases with calcium carbonate or hydroxide in the form of slurry to convert the sulfur oxides into caso3; a second step of contacting O2 with the resulting slurry to convert CaSo3 into caso4; a third step of separating caso4 and mother liquor from the resulting slurry; and a fourth step of preparing a slurry of calcium carbonate or hydroxide to be employed in the first step, from the mother liquor, the pHs of the slurry and the mother liquor in the first and fourth steps being adjusted to 5 or higher by adding alkali such as sodium carbonate. According to the present process, it is possible to prevent hindrance of hf and al contained in dust to the reaction of so2absorbent (CaCO3 or Ca(OH)2) with SO2 gas, and thereby improve percentage desulfurization and also obtain a high quality gypsum.

  16. Selenium speciation in flue desulfurization residues.

    PubMed

    Zhong, Liping; Cao, Yan; Li, Wenying; Xie, Kechang; Pan, Wei-Ping

    2011-01-01

    Flue gas from coal combustion contains significant amounts of volatile selenium (Se). The capture of Se in the flue gas desulfurization (FGD) scrubber unit has resulted in a generation of metal-laden residues. It is important to determine Se speciation to understand the environmental impact of its disposal. A simple method has been developed for selective inorganic Se(IV), Se(VI) and organic Se determination in the liquid-phase FGD residues by hydride generation atomic fluorescence spectrometry (AFS). It has been determined that Se(IV), Se(VI) and organic Se can be accurately determined with detection limits (DL) of 0.05, 0.06 and 0.06 microg/L, respectively. The accuracy of the proposed method was evaluated by analyzing the certified reference material, NIST CRM 1632c, and also by analyzing spiked tap-water samples. Analysis indicates that the concentration of Se is high in FGD liquid residues and primarily exists in a reduced state as selenite (Se(IV)). The toxicity of Se(IV) is the strongest of all Se species. Flue gas desulfurization residues pose a serious environmental risk.

  17. PULSION® HP: Tunable, High Productivity Plasma Doping

    NASA Astrophysics Data System (ADS)

    Felch, S. B.; Torregrosa, F.; Etienne, H.; Spiegel, Y.; Roux, L.; Turnbaugh, D.

    2011-01-01

    Plasma doping has been explored for many implant applications for over two decades and is now being used in semiconductor manufacturing for two applications: DRAM polysilicon counter-doping and contact doping. The PULSION HP is a new plasma doping tool developed by Ion Beam Services for high-volume production that enables customer control of the dominant mechanism—deposition, implant, or etch. The key features of this tool are a proprietary, remote RF plasma source that enables a high density plasma with low chamber pressure, resulting in a wide process space, and special chamber and wafer electrode designs that optimize doping uniformity.

  18. Molecular dynamics simulation on HP1 protein binding by histone H3 tail methylation and phosphorylation

    NASA Astrophysics Data System (ADS)

    Jiang, Yan-Ke; Zou, Jian-Wei; Wu, Yu-Qian; Zhang, Na; Yu, Qing-Sen; Jiang, Yong-Jun

    Trimethylation of histone H3 lysine 9 is important for recruiting heterochromatin protein 1 (HP1) to discrete regions of the genome, thereby regulating gene expression, chromatin packaging, and heterochromatin formation. Phosphorylation of histone H3 has been linked with mitotic chromatin condensation. During mitosis in vivo, H3 lysine 9 methylation and serine 10 phosphorylation can occur concomitantly on the same histone tail, whereas the influence of phosphorylation to trimethylation H3 tail recruiting HP1 remains controversial. In this work, molecular dynamics simulation of HP1 complexed with both trimethylated and phosphorylated H3 tail were performed and compared with the results from the previous methylated H3-HP1 trajectory. It is clear from the 10-ns dynamics simulation that two adjacent posttranslational modifications directly increase the flexibility of the H3 tail and weaken HP1 binding to chromatin. A combinatorial readout of two adjacent posttranslational modifications-a stable methylation and a dynamic phosphorylation mark-establish a regulatory mechanism of protein-protein interactions.

  19. Recovery of lead from lead paste in spent lead acid battery by hydrometallurgical desulfurization and vacuum thermal reduction.

    PubMed

    Ma, Yunjian; Qiu, Keqiang

    2015-06-01

    Lead sulfate, lead oxides and lead metal are the main component of lead paste in spent lead acid battery. When lead sulfate was desulfurized and transformed into lead carbonate by sodium carbonate, lead metal and lead oxides remained unchanged. Lead carbonate is easily decomposed to lead oxide and carbon dioxide under high temperature. Namely, vacuum thermal process is the reduction reaction of lead oxides. A compatible environmental process consisted of hydrometallurgical desulfurization and vacuum thermal reduction to recycle lead was investigated in this research. Lead paste was firstly desulfurized with sodium carbonate, by which, the content of sulfur declined from 7.87% to 0.26%. Then, the desulfurized lead paste was reduced by charcoal under vacuum. Under the optimized reaction conditions, i.e., vacuum thermal reduction at temperature 850°C under 20 Pa for 45 min, a 22.11×10(-2) g cm(-2) min(-1) reduction rate, and a 98.13% direct recovery ratio of fine lead (99.77%) had been achieved, respectively.

  20. HIGH EFFICIENCY DESULFURIZATION OF SYNTHESIS GAS

    SciTech Connect

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

    2003-11-01

    Mixed metal oxides containing CeO{sub 2} and ZrO{sub 2} are being studied as high temperature desulfurization sorbents capable of achieving the DOE Vision 21 target of 1 ppmv or less H{sub 2}S. The research is justified by recent results in this laboratory that showed that reduced CeO{sub 2}, designated CeOn (1.5 < n < 2.0), is capable of achieving the 1 ppmv target in highly reducing gas atmospheres. The addition of ZrO{sub 2} has improved the performance of oxidation catalysts and three-way automotive catalysts containing CeO{sub 2}, and should have similar beneficial effects on CeO{sub 2} desulfurization sorbents. An electrochemical method for synthesizing CeO{sub 2}-ZrO{sub 2} was developed and the products were characterized by XRD and TEM during year 01. Nanocrystalline particles having a diameter of about 5 nm and containing from approximately 10 mol% to 80 mol% ZrO{sub 2} were prepared. XRD analysis showed the product to be a solid solution at low ZrO{sub 2} contents with a separate ZrO{sub 2} phase emerging at higher ZrO{sub 2} levels. Unfortunately, the quantity of CeO{sub 2}-ZrO{sub 2} that could be prepared electrochemically was too small to permit full desulfurization testing. Also during year 01 a laboratory-scale fixed-bed reactor was constructed for desulfurization testing. All components of the reactor and analytical systems that may be exposed to low concentrations of H{sub 2}S are constructed of quartz, Teflon, or silcosteel. Reactor product gas composition as a function of time is determined using a Varian 3800 gas chromatograph equipped with a pulsed flame photometric detector (PFPD) for measuring low H{sub 2}S concentrations (<{approx}10 ppmv) and a thermal conductivity detector (TCD) for higher concentrations of H{sub 2}S. Larger quantities of CeO{sub 2}-ZrO{sub 2} mixtures from other sources, including mixtures prepared in this laboratory using a coprecipitation procedure, have been obtained. Much of the work during year 02 consisted of

  1. HIGH EFFICIENCY DESULFURIZATION OF SYNTHESIS GAS

    SciTech Connect

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

    2004-03-01

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

  2. HIGH EFFICIENCY DESULFURIZATION OF SYNTHESIS GAS

    SciTech Connect

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

    2002-11-01

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

  3. Theoretical study on the polar hydrogen-π (Hp-π) interactions between protein side chains

    PubMed Central

    2013-01-01

    Background In the study of biomolecular structures and interactions the polar hydrogen-π bonds (Hp-π) are an extensive molecular interaction type. In proteins 11 of 20 natural amino acids and in DNA (or RNA) all four nucleic acids are involved in this type interaction. Results The Hp-π in proteins are studied using high level QM method CCSD/6-311 + G(d,p) + H-Bq (ghost hydrogen basis functions) in vacuum and in solutions (water, acetonitrile, and cyclohexane). Three quantum chemical methods (B3LYP, CCSD, and CCSD(T)) and three basis sets (6-311 + G(d,p), TZVP, and cc-pVTZ) are compared. The Hp-π donors include R2NH, RNH2, ROH, and C6H5OH; and the acceptors are aromatic amino acids, peptide bond unit, and small conjugate π-groups. The Hp-π interaction energies of four amino acid pairs (Ser-Phe, Lys-Phe, His-Phe, and Tyr-Phe) are quantitatively calculated. Conclusions Five conclusion points are abstracted from the calculation results. (1) The common DFT method B3LYP fails in describing the Hp-π interactions. On the other hand, CCSD/6-311 + G(d,p) plus ghost atom H-Bq can yield better results, very close to the state-of-the-art method CCSD(T)/cc-pVTZ. (2) The Hp-π interactions are point to π-plane interactions, possessing much more interaction conformations and broader energy range than other interaction types, such as common hydrogen bond and electrostatic interactions. (3) In proteins the Hp-π interaction energies are in the range 10 to 30 kJ/mol, comparable or even larger than common hydrogen bond interactions. (4) The bond length of Hp-π interactions are in the region from 2.30 to 3.00 Å at the perpendicular direction to the π-plane, much longer than the common hydrogen bonds (~1.9 Å). (5) Like common hydrogen bond interactions, the Hp-π interactions are less affected by solvation effects. PMID:23705926

  4. Plane flame furnace combustion tests on JPL desulfurized coal

    NASA Technical Reports Server (NTRS)

    Reuther, J. J.; Kim, H. T.; Lima, J. G. H.

    1982-01-01

    The combustion characteristics of three raw bituminous (PSOC-282 and 276) and subbituminous (PSOC-230) coals, the raw coals partially desulfurized (ca -60%) by JPL chlorinolysis, and the chlorinated coals more completely desulfurized (ca -75%) by JPL hydrodesulfurization were determined. The extent to which the combustion characteristics of the untreated coals were altered upon JPL sulfur removal was examined. Combustion conditions typical of utility boilers were simulated in the plane flame furnace. Upon decreasing the parent coal voltaile matter generically by 80% and the sulfur by 75% via the JPL desulfurization process, ignition time was delayed 70 fold, burning velocity was retarded 1.5 fold, and burnout time was prolonged 1.4 fold. Total flame residence time increased 2.3 fold. The JPL desulfurization process appears to show significant promise for producing technologically combustible and clean burning (low SO3) fuels.

  5. HIGH EFFICIENCY DESULFURIZATION OF SYNTHESIS GAS

    SciTech Connect

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

    2001-11-01

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

  6. Advanced sulfur control concepts for hot gas desulfurization technology

    SciTech Connect

    1998-09-01

    The objective of this project is to develop a hot-gas desulfurization process scheme for control of H{sub 2}S in HTHP coal gas that can be more simply and economically integrated with known regenerable sorbents in DOE/METC-sponsored work than current leading hot-gas desulfurization technologies. In addition to being more economical, the process scheme to be developed must yield an elemental sulfur byproduct.

  7. hp-Pseudospectral method for solving continuous-time nonlinear optimal control problems

    NASA Astrophysics Data System (ADS)

    Darby, Christopher L.

    2011-12-01

    In this dissertation, a direct hp-pseudospectral method for approximating the solution to nonlinear optimal control problems is proposed. The hp-pseudospectral method utilizes a variable number of approximating intervals and variable-degree polynomial approximations of the state within each interval. Using the hp-discretization, the continuous-time optimal control problem is transcribed to a finite-dimensional nonlinear programming problem (NLP). The differential-algebraic constraints of the optimal control problem are enforced at a finite set of collocation points, where the collocation points are either the Legendre-Gauss or Legendre-Gauss-Radau quadrature points. These sets of points are chosen because they correspond to high-accuracy Gaussian quadrature rules for approximating the integral of a function. Moreover, Runge phenomenon for high-degree Lagrange polynomial approximations to the state is avoided by using these points. The key features of the hp-method include computational sparsity associated with low-order polynomial approximations and rapid convergence rates associated with higher-degree polynomials approximations. Consequently, the hp-method is both highly accurate and computationally efficient. Two hp-adaptive algorithms are developed that demonstrate the utility of the hp-approach. The algorithms are shown to accurately approximate the solution to general continuous-time optimal control problems in a computationally efficient manner without a priori knowledge of the solution structure. The hp-algorithms are compared empirically against local (h) and global (p) collocation methods over a wide range of problems and are found to be more efficient and more accurate. The hp-pseudospectral approach developed in this research not only provides a high-accuracy approximation to the state and control of an optimal control problem, but also provides high-accuracy approximations to the costate of the optimal control problem. The costate is approximated by

  8. An unusually simple HP1 gene set in Hymenopteran insects.

    PubMed

    Fang, C; Schmitz, L; Ferree, P M

    2015-12-01

    The heterochromatin protein 1 (HP1) gene family includes a set of paralogs in higher eukaryotes that serve fundamental roles in heterochromatin structure and maintenance, and other chromatin-related functions. At least 10 full and 16 partial HP1 genes exist among Drosophila species, with multiple gene gains, losses, and sub-functionalizations within this insect group. An important question is whether this diverse set of HP1 genes and their dynamic evolution represent the standard rule in eukaryotic groups. Here we have begun to address this question by bio-informatically identifying the HP1 family genes in representative species of the insect order Hymenoptera, which includes all ants, bees, wasps, and sawflies. Compared to Drosophila species, Hymenopterans have a much simpler set of HP1 genes, including one full and two partial HP1s. All 3 genes appear to have been present in the common ancestor of the Hymenopterans and they derive from a Drosophila HP1B-like gene. In ants, a partial HP1 gene containing only a chromoshadow domain harbors amino acid changes at highly conserved sites within the PxVxL recognition region, suggesting that this gene has undergone sub-functionalization. In the jewel wasp Nasonia vitripennis, the full HP1 and partial chromoshadow-only HP1 are expressed in both germ line and somatic tissues. However, the partial chromodomain-only HP1 is expressed exclusively in the ovary and testis, suggesting that it may have a specialized chromatin role during gametogenesis. Our findings demonstrate that the HP1 gene family is much simpler and evolutionarily less dynamic within the Hymenopterans compared to the much younger Drosophila group, a pattern that may reflect major differences in the range of chromatin-related functions present in these and perhaps other insect groups.

  9. Olefins can limit desulfurization of reformer feedstock

    SciTech Connect

    Ali, S.A.; Anabtawi, J.A.

    1995-07-03

    Pilot plant studies have shown that the presence of even very small amounts of olefins may limit the desulfurization of reformer feedstocks to trace levels. Engineers at the Research Institute of King Fahd University of Petroleum and Minerals observed under typical industrial conditions the recombination reaction of olefins with hydrogen sulfide to form mercaptans. The results indicate that the advantage of using highly active (third generation) CoMo hydrotreating catalysts can be masked by these reactions if the olefins are not saturated. The trend in naphtha reforming is to use high-rhenium, bimetallic catalysts that display less resistance to sulfur than do balanced Pt-Re catalysts. Due consideration, therefore, should be given to these undesirable recombination reactions while designing hydrotreaters and selecting hydrodesulfurization (HDS) and reforming catalysts. The paper discusses catalysts and feedstock tests, catalyst activity, temperature effects, space velocity, feedstock effect, catalyst performance, and recommendations.

  10. Flue gas desulfurization method and apparatus

    DOEpatents

    Madden, Deborah A.; Farthing, George A.

    1998-08-18

    A combined furnace limestone injection and dry scrubber flue gas desulfurization (FGD) system collects solids from the flue gas stream in first particulate collection device located downstream of an outlet of a convection pass of the furnace and upstream of the dry scrubber. The collected solids are diverted to the dry scrubber feed slurry preparation system to increase sulfur oxide species removal efficiency and sorbent utilization. The level of lime in the feed slurry provided to the dry scrubber is thus increased, which enhances removal of sulfur oxide species in the dry scrubber. The decreased particulate loading to the dry scrubber helps maintain a desired degree of free moisture in the flue gas stream entering the dry scrubber, which enhances sulfur oxide species removal both in the dry scrubber and downstream particulate collector, normally a baghouse.

  11. Flue gas desulfurization method and apparatus

    DOEpatents

    Madden, Deborah A.; Farthing, George A.

    1998-09-29

    A combined furnace limestone injection and dry scrubber flue gas desulfurization (FGD) system collects solids from the flue gas stream in first particulate collection device located downstream of an outlet of a convection pass of the furnace and upstream of the dry scrubber. The collected solids are diverted to the dry scrubber feed slurry preparation system to increase sulfur oxide species removal efficiency and sorbent utilization. The level of lime in the feed slurry provided to the dry scrubber is thus increased, which enhances removal of sulfur oxide species in the dry scrubber. The decreased particulate loading to the dry scrubber helps maintain a desired degree of free moisture in the flue gas stream entering the dry scrubber, which enhances sulfur oxide species removal both in the dry scrubber and downstream particulate collector, normally a baghouse.

  12. Flue gas desulfurization method and apparatus

    DOEpatents

    Madden, D.A.; Farthing, G.A.

    1998-08-18

    A combined furnace limestone injection and dry scrubber flue gas desulfurization (FGD) system collects solids from the flue gas stream in first particulate collection device located downstream of an outlet of a convection pass of the furnace and upstream of the dry scrubber. The collected solids are diverted to the dry scrubber feed slurry preparation system to increase sulfur oxide species removal efficiency and sorbent utilization. The level of lime in the feed slurry provided to the dry scrubber is thus increased, which enhances removal of sulfur oxide species in the dry scrubber. The decreased particulate loading to the dry scrubber helps maintain a desired degree of free moisture in the flue gas stream entering the dry scrubber, which enhances sulfur oxide species removal both in the dry scrubber and downstream particulate collector, normally a baghouse. 5 figs.

  13. Flue gas desulfurization method and apparatus

    DOEpatents

    Madden, D.A.; Farthing, G.A.

    1998-09-29

    A combined furnace limestone injection and dry scrubber flue gas desulfurization (FGD) system collects solids from the flue gas stream in first particulate collection device located downstream of an outlet of a convection pass of the furnace and upstream of the dry scrubber. The collected solids are diverted to the dry scrubber feed slurry preparation system to increase sulfur oxide species removal efficiency and sorbent utilization. The level of lime in the feed slurry provided to the dry scrubber is thus increased, which enhances removal of sulfur oxide species in the dry scrubber. The decreased particulate loading to the dry scrubber helps maintain a desired degree of free moisture in the flue gas stream entering the dry scrubber, which enhances sulfur oxide species removal both in the dry scrubber and downstream particulate collector, normally a baghouse. 5 figs.

  14. Limestone-gypsum flue gas desulfurization process

    SciTech Connect

    Kuroda, H.; Hashimoto, T.; Kanda, O.; Nishimura, M.; Nishimura, T.; Nozawa, S.

    1984-12-11

    A flue gas desulfurization process capable of producing a high purity gypsum and also making equipment employed as minimum as possible is provided, which process comprises the steps of cooling and dedusting flue gas containing SO /SUB x/ ; contacting the cooled gas with a slurry containing limestone to remove SO /SUB x/ by absorption and also form CaSO/sub 3/; controlling the pH of the resulting slurry and then blowing air therein to form gypsum; and separating gypsum from the resulting slurry. As a modification of the above process, the slurry of the above second absorption step is further fed to the above first cooling step where unreacted limestone and SO /SUB x/ are reacted to form CaSO/sub 3/.

  15. Developing clean fuels: Novel techniques for desulfurization

    NASA Astrophysics Data System (ADS)

    Nehlsen, James P.

    The removal of sulfur compounds from petroleum is crucial to producing clean burning fuels. Sulfur compounds poison emission control catalysts and are the source of acid rain. New federal regulations require the removal of sulfur in both gasoline and diesel to very low levels, forcing existing technologies to be pushed into inefficient operating regimes. New technology is required to efficiently produce low sulfur fuels. Two processes for the removal of sulfur compounds from petroleum have been developed: the removal of alkanethiols by heterogeneous reaction with metal oxides; and oxidative desulfurization of sulfides and thiophene by reaction with sulfuric acid. Alkanethiols, common in hydrotreated gasoline, can be selectively removed and recovered from a hydrocarbon stream by heterogeneous reaction with oxides of Pb, Hg(II), and Ba. The choice of reactive metal oxides may be predicted from simple thermodynamic considerations. The reaction is found to be autocatalytic, first order in water, and zero order in thiol in the presence of excess oxide. The thiols are recovered by reactive extraction with dilute oxidizing acid. The potential for using polymer membrane hydrogenation reactors (PEMHRs) to perform hydrogenation reactions such as hydrodesulfurization is explored by hydrogenating ketones and olefins over Pt and Au group metals. The dependence of reaction rate on current density suggests that the first hydrogen addition to the olefin is the rate limiting step, rather than the adsorption of hydrogen, for all of the metals tested. PEMHRs proved unsuccessful in hydrogenating sulfur compounds to perform HDS. For the removal of sulfides, a two-phase reactor is used in which concentrated sulfuric acid oxidizes aromatic and aliphatic sulfides present in a hydrocarbon solvent, generating sulfoxides and other sulfonated species. The polar oxidized species are extracted into the acid phase, effectively desulfurizing the hydrocarbon. A reaction scheme is proposed for this

  16. Proteomics and Metabolomics Analyses to Elucidate the Desulfurization Pathway of Chelatococcus sp.

    PubMed Central

    Chaudhuri, Mihir K.

    2016-01-01

    Desulfurization of dibenzothiophene (DBT) and alkylated DBT derivatives present in transport fuel through specific cleavage of carbon-sulfur (C-S) bonds by a newly isolated bacterium Chelatococcus sp. is reported for the first time. Gas chromatography-mass spectrometry (GC-MS) analysis of the products of DBT degradation by Chelatococcus sp. showed the transient formation of 2-hydroxybiphenyl (2-HBP) which was subsequently converted to 2-methoxybiphenyl (2-MBP) by methylation at the hydroxyl group of 2-HBP. The relative ratio of 2-HBP and 2-MBP formed after 96 h of bacterial growth was determined at 4:1 suggesting partial conversion of 2-HBP or rapid degradation of 2-MBP. Nevertheless, the enzyme involved in this conversion process remains to be identified. This production of 2-MBP rather than 2-HBP from DBT desulfurization has a significant metabolic advantage for enhancing the growth and sulfur utilization from DBT by Chelatococcus sp. and it also reduces the environmental pollution by 2-HBP. Furthermore, desulfurization of DBT derivatives such as 4-M-DBT and 4, 6-DM-DBT by Chelatococcus sp. resulted in formation of 2-hydroxy-3-methyl-biphenyl and 2-hydroxy –3, 3/- dimethyl-biphenyl, respectively as end product. The GC and X-ray fluorescence studies revealed that Chelatococcus sp. after 24 h of treatment at 37°C reduced the total sulfur content of diesel fuel by 12% by per gram resting cells, without compromising the quality of fuel. The LC-MS/MS analysis of tryptic digested intracellular proteins of Chelatococcus sp. when grown in DBT demonstrated the biosynthesis of 4S pathway desulfurizing enzymes viz. monoxygenases (DszC, DszA), desulfinase (DszB), and an NADH-dependent flavin reductase (DszD). Besides, several other intracellular proteins of Chelatococcus sp. having diverse biological functions were also identified by LC-MS/MS analysis. Many of these enzymes are directly involved with desulfurization process whereas the other enzymes/proteins support

  17. Pattern Recognition of Adsorbing HP Lattice Proteins

    NASA Astrophysics Data System (ADS)

    Wilson, Matthew S.; Shi, Guangjie; Wüst, Thomas; Landau, David P.; Schmid, Friederike

    2015-03-01

    Protein adsorption is relevant in fields ranging from medicine to industry, and the qualitative behavior exhibited by course-grained models could shed insight for further research in such fields. Our study on the selective adsorption of lattice proteins utilizes the Wang-Landau algorithm to simulate the Hydrophobic-Polar (H-P) model with an efficient set of Monte Carlo moves. Each substrate is modeled as a square pattern of 9 lattice sites which attract either H or P monomers, and are located on an otherwise neutral surface. The fully enumerated set of 102 unique surfaces is simulated with each protein sequence. A collection of 27-monomer sequences is used- each of which is non-degenerate and protein-like. Thermodynamic quantities such as the specific heat and free energy are calculated from the density of states, and are used to investigate the adsorption of lattice proteins on patterned substrates. Research supported by NSF.

  18. HP41C formation evaluation programs

    SciTech Connect

    Hallenburg, J.K.

    1984-01-01

    Over 30 programmable calculator programs for fast, on-the-job analysis are included in this book. They are short, simple, and useable in the field, office, or laboroatory. Each program comes with equations and simple solutions that are geared around the HP41C programmable calculator. The programs are useful for petroleum well log analysis as well as mineral and engineering applications. Contents include: Preliminary Methods - estimating and filtrate, solution temperature correction; Determining R/sub WE/, and calculating average temperature gradient downhole; Analysis Methods - calculating porosity, determining water saturation, acoustic-neutron crossplot for lithology and porosity, and estimating permeability of a sandstone; Troubleshooting Methods - obtaining probable density from porosity and Obtaining R/sub O/ and R/sub XO/; General Programs - determining area under a logged curve, calculating vertical thickness of a bed, determining horizontal displacement of a deviated hole, and estimating cuttings lag while drilling.

  19. HP1 Recruitment in the Absence of Argonaute Proteins in Drosophila

    PubMed Central

    Moshkovich, Nellie; Lei, Elissa P.

    2010-01-01

    Highly repetitive and transposable element rich regions of the genome must be stabilized by the presence of heterochromatin. A direct role for RNA interference in the establishment of heterochromatin has been demonstrated in fission yeast. In metazoans, which possess multiple RNA–silencing pathways that are both functionally distinct and spatially restricted, whether RNA silencing contributes directly to heterochromatin formation is not clear. Previous studies in Drosophila melanogaster have suggested the involvement of both the AGO2-dependent endogenous small interfering RNA (endo-siRNA) as well as Piwi-interacting RNA (piRNA) silencing pathways. In order to determine if these Argonaute genes are required for heterochromatin formation, we utilized transcriptional reporters and chromatin immunoprecipitation of the critical factor Heterochromatin Protein 1 (HP1) to monitor the heterochromatic state of piRNA clusters, which generate both endo-siRNAs and the bulk of piRNAs. Surprisingly, we find that mutation of AGO2 or piwi increases silencing at piRNA clusters corresponding to an increase of HP1 association. Furthermore, loss of piRNA production from a single piRNA cluster results in genome-wide redistribution of HP1 and reduction of silencing at a distant heterochromatic site, suggesting indirect effects on HP1 recruitment. Taken together, these results indicate that heterochromatin forms independently of endo-siRNA and piRNA pathways. PMID:20300658

  20. DEVELOPMENT OF ADVANCED HOT-GAS DESULFURIZATION PROCESSES

    SciTech Connect

    K. Jothimurugesan; Santosh K. Gangwal

    2000-12-01

    The techniques employed in this project have successfully demonstrated the feasibility of preparing sorbents that achieve greater than 99% H{sub 2}S removal at temperatures 480 C and that retain their activity over 50 cycles. Fundamental understanding of phenomena leading to chemical deactivation and high regeneration light-off temperature has enabled us to successfully prepare and scale up a FHR-32 sorbent that showed no loss in reactivity and capacity over 50 cycles. This sorbent removed H{sub 2}S below 80 ppmv and lighted-off nicely at 480 C during regeneration. Overall the test is a success with potential for an optimized FHR-32 to be a candidate for Sierra-Pacific. An advanced attrition resistant hot-gas desulfurization sorbent that can eliminate the problematic SO{sub 2} tail gas and yield elemental sulfur directly has been developed. Attrition resistant Zn-Fe sorbent (AHI-2) formulations have been prepared that can remove H{sub 2}S to below 20 ppmv from coal gas and can be regenerated using SO{sub 2} to produce elemental sulfur.

  1. High Contacting Efficience Carrier Structures & Porcesses for Liquid Phase Regenerable Desulfurization of Logistic Fuels

    DTIC Science & Technology

    2011-02-21

    Phase Regenerable Desulfurization of Logistic Fuels 5a. CONTRACT NUMBER Sb. GRANT NUMBER N00014-06-1-1165 6c. PROGRAM ELEMENT NUMBER 6. AUTHOR...developed and characterized. The adsorbent’s formulation, preparation procedure, desulfurization conditions and regeneration procedure have established and...enables novel process design for the logistic fuel desulfurization . 15. SUBJECT TERMS desulfurization , liquid fuel, silver, titania 16. SECURITY

  2. Functional study of gene hp0169 in Helicobacter pylori pathogenesis.

    PubMed

    Zhao, Huilin; Ji, Xiaofei; Chen, Xingxing; Li, Jiaojiao; Zhang, Ying; Du, Zhenzhen; Zhang, Yumei; Li, Boqing

    2017-03-01

    Many virulence genes have been reported to play important roles in Helicobacter pylori pathogenesis. However the detailed mechanisms of many of them have not been completely clear. In this study, we found gene hp0169, encoding a putative collagenase (HpPrtC), was involved in pathogenesis of H. pylori. Recombinant HpPrtC shows activities to both native and heat-denatured collagens. This result indicated that HpPrtC may act as a virulence factor to help the bacterium colonize in their host stomach by degrading surrounding collagens. hp0169 was deleted by homologous recombination to study its function in bacterium-host cell interaction. For the pathogenic functions on the host cells, the hp0169 mutant exhibits no significant changes on inducing apoptosis of GES-1 cells. However, the viability and proliferation rate of GES-1 cells infected with mutant strain were higher than the cells infected with wild-type strain. These results indicated that except for its collagenolytic activity, HpPrtC might participate in H. pylori pathogenesis through an additional pathway. Functional studies on hp0169 involved in pathogenesis would shed light on deep understanding of the pathogenic mechanism of H. pylori.

  3. A NOVEL APPROACH TO CATALYTIC DESULFURIZATION OF COAL

    SciTech Connect

    John G. Verkade

    2001-11-01

    Column chromatographic separation of the S=PBu{sub 3}/PBu{sub 3} product mixture followed by weighing the S=PBu{sub 3}, and by vacuum distillation of S=PBu{sub 3}/PBu{sub 3}mixture followed by gas chromatographic analysis are described. Effects of coal mesh size, pre-treatment with methanol Coal (S) + excess PR{sub 3} {yields} Coal + S=PR{sub 3}/PBu{sub 3} and sonication on sulfur removal by PBu{sub 3} revealed that particle size was not observed to affect desulfurization efficiency in a consistent manner. Coal pretreatment with methanol to induce swelling or the addition of a filter aid such as Celite reduced desulfurization efficiency of the PBu{sub 3} and sonication was no more effective than heating. A rationale is put forth for the lack of efficacy of methanol pretreatment of the coal in desulfurization runs with PBu{sub 3}. Coal desulfurization with PBu{sub 3} was not improved in the presence of miniscule beads of molten lithium or sodium as a desulfurizing reagent for SPBu{sub 3} in a strategy aimed at regenerating PBu{sub 3} inside coal pores. Although desulfurization of coals did occur in sodium solutions in liquid ammonia, substantial loss of coal mass was also observed. Of particular concern is the mass balance in the above reaction, a problem which is described in some detail. In an effort to solve this difficulty, a specially designed apparatus is described which we believe can solve this problem reasonably effectively. Elemental sodium was found to remove sulfur quantitatively from a variety of polycyclic organosulfur compounds including dibenzothiophene and benzothiophene under relatively mild conditions (150 C) in a hydrocarbon solvent without requiring the addition of a hydrogen donor. Lithium facilitates the same reaction at a higher temperature (254 C). Mechanistic pathways are proposed for these transformations. Curiously, dibenzothiophene and its corresponding sulfone was virtually quantitatively desulfurized in sodium solutions in liquid

  4. CONVERSION EXTRACTION DESULFURIZATION (CED) PHASE III

    SciTech Connect

    James Boltz

    2005-03-01

    This project was undertaken to refine the Conversion Extraction Desulfurization (CED) technology to efficiently and economically remove sulfur from diesel fuel to levels below 15-ppm. CED is considered a generic term covering all desulfurization processes that involve oxidation and extraction. The CED process first extracts a fraction of the sulfur from the diesel, then selectively oxidizes the remaining sulfur compounds, and finally extracts these oxidized materials. The Department of Energy (DOE) awarded Petro Star Inc. a contract to fund Phase III of the CED process development. Phase III consisted of testing a continuous-flow process, optimization of the process steps, design of a pilot plant, and completion of a market study for licensing the process. Petro Star and the Degussa Corporation in coordination with Koch Modular Process Systems (KMPS) tested six key process steps in a 7.6-centimeter (cm) (3.0-inch) inside diameter (ID) column at gas oil feed rates of 7.8 to 93.3 liters per hour (l/h) (2.1 to 24.6 gallons per hour). The team verified the technical feasibility with respect to hydraulics for each unit operation tested and successfully demonstrated pre-extraction and solvent recovery distillation. Test operations conducted at KMPS demonstrated that the oxidation reaction converted a maximum of 97% of the thiophenes. The CED Process Development Team demonstrated that CED technology is capable of reducing the sulfur content of light atmospheric gas oil from 5,000-ppm to less than 15-ppm within the laboratory scale. In continuous flow trials, the CED process consistently produced fuel with approximately 20-ppm of sulfur. The process economics study calculated an estimated process cost of $5.70 per product barrel. The Kline Company performed a marketing study to evaluate the possibility of licensing the CED technology. Kline concluded that only 13 refineries harbored opportunity for the CED process. The Kline study and the research team's discussions with

  5. 40 HP Electro-Mechanical Actuator

    NASA Technical Reports Server (NTRS)

    Fulmer, Chris

    1996-01-01

    This report summarizes the work performed on the 40 BP electro-mechanical actuator (EMA) system developed on NASA contract NAS3-25799 for the NASA National Launch System and Electrical Actuation (ELA) Technology Bridging Programs. The system was designed to demonstrate the capability of large, high power linear ELA's for applications such as Thrust Vector Control (TVC) on rocket engines. It consists of a motor controller, high frequency power source, drive electronics and a linear actuator. The power source is a 25kVA 20 kHz Mapham inverter. The drive electronics are based on the pulse population modulation concept and operate at a nominal frequency of 40 kHz. The induction motor is a specially designed high speed, low inertia motor capable of a 68 peak HP. The actuator was originally designed by MOOG Aerospace under an internal R & D program to meet Space Shuttle Main Engine (SSME) TVC requirements. The design was modified to meet this programs linear rate specification of 7.4 inches/second. The motor and driver were tested on a dynamometer at the Martin Marietta Space Systems facility. System frequency response and step response tests were conducted at the Marshall Space Flight Center facility. A complete description of the system and all test results can be found in the body of the report.

  6. Flue gas desulfurization: Physicochemical and biotechnological approaches

    SciTech Connect

    Pandey, R.A.; Biswas, R.; Chakrabarti, T.; Devotta, S.

    2005-07-01

    Various flue gas desulfurization processes - physicochemical, biological, and chemobiological - for the reduction of emission of SO{sub 2} with recovery of an economic by-product have been reviewed. The physicochemical processes have been categorized as 'once-through' and 'regenerable.' The prominent once-through technologies include wet and dry scrubbing. The wet scrubbing technologies include wet limestone, lime-inhibited oxidation, limestone forced oxidation, and magnesium-enhanced lime and sodium scrubbing. The dry scrubbing constitutes lime spray drying, furnace sorbent injection, economizer sorbent injection, duct sorbent injection, HYPAS sorbent injection, and circulating fluidized bed treatment process. The regenerable wet and dry processes include the Wellman Lord's process, citrate process, sodium carbonate eutectic process, magnesium oxide process, amine process, aqueous ammonia process, Berglau Forchung's process, and Shell's process. Besides these, the recently developed technologies such as the COBRA process, the OSCAR process, and the emerging biotechnological and chemobiological processes are also discussed. A detailed outline of the chemistry, the advantages and disadvantages, and the future research and development needs for each of these commercially viable processes is also discussed.

  7. Method for operating a flue gas desulfurization

    SciTech Connect

    Karger, R.; Weinzierl, K.

    1983-02-01

    A method of operating a flue gas desulfurization with a steam power plant heated with fossil fuels. The sulfur dioxide contained in the flue gas is removed in a wash tower by means of an excess of milk of lime or limestone, and the resulting sulfite is oxidized with air at a low ph-value into calcium sulfate. The non-converted milk of lime or limestone is neutralized at least partially by an addition of acid waste waters from a complete desalination plant for the supply water, and/or by an addition of acid condensate from the flue or chimney of the steam power plant. An installation for carrying out the method of the present invention includes a wash tower having flue gas flowing therethrough, an oxidation tower having air flowing therethrough, milk of lime or limestone supply into the wash tower, and a delivery device for the wash liquid in the wash tower and in the oxidation tower, with the device having a pump for liquid drawn off from the sump of the wash tower. The sump of the wash tower is connected with a supply line for acid waste water from a complete desalination plant, and/or with a supply line for acid condensate from the chimney or flue of the steam power plant.

  8. Coal desulfurization by low temperature chlorinolysis, phase 3

    NASA Technical Reports Server (NTRS)

    Kalvinskas, J. J.; Rohatgi, N. K.; Ernest, J.

    1981-01-01

    Laboratory scale, bench scale batch reactor, and minipilot plant tests were conducted on 22 bituminous, subbituminous, and lignite coals. Chemical pretreatment and post treatment of coals relative to the chlorination were tried as a means of enhancing desulfurization by the chlorinolysis process. Elevated temperature (500-700 C) hydrogen treatment of chlorinolysis-processed coal at atmospheric pressure was found to substantially increase coal desulfurization up to 90 percent. Sulfur forms, proximate and ultimate analyses of the processed coal are included. Minipilot plant operation indicates that the continuous flow reactor provides coal desulfurization results comparable to those obtained in the batch reactor. Seven runs were conducted at coal feed rates of 1.5 to 8.8 kg per hour using water and methylchloroform solvents, gaseous chlorine feed of 3 to 31.4 SCFH at 21 to 70 C, and atmospheric pressure for retention times of 20 to 120 minutes.

  9. Ultrasonic coal-wash for de-sulfurization.

    PubMed

    Ambedkar, B; Nagarajan, R; Jayanti, S

    2011-05-01

    Coal is the one of the world's most abundant fossil fuel resources. It is not a clean fuel, as it contains ash and sulfur. SOx as a pollutant are a real threat to both the ecosystem and to human health. There are numerous de-sulfurization methods to control SO(2) emissions. Nowadays, online flue gas de-sulfurization is being used as one such method to remove sulfur from coal during combustion. The biggest disadvantage associated with this method is formation of by-products (FGD gypsum). A way for effective usage of FGD gypsum has not yet been found. This will lead to acute and chronic effects to humans as well as plants. Power ultrasound can be used for the beneficiation of coal by the removal of sulfur from coal prior to coal combustion. The main effects of ultrasound in liquid medium are acoustic cavitation and acoustic streaming. The process of formation, growth and implosion of bubbles is called cavitation. Bulk fluid motion due to sound energy absorption is known as acoustic streaming. In addition, coupling of an acoustic field to water produces OH radicals, H(2)O(2), O(2), ozone and HO(2) that are strong oxidizing agents. Oxidation that occurs due to ultrasound is called Advanced Oxidation Process (AOP). It converts sulfur from coal to water-soluble sulphates. Conventional chemical-based soaking and stirring methods are compared here to ultrasonic methods of de-sulfurization. The main advantages of ultrasonic de-sulfurization over conventional methods, the mechanism involved in ultrasonic de-sulfurization and the difference between aqueous-based and solvent-based (2N HNO(3), 3-volume percentage H(2)O(2)) de-sulfurization are investigated experimentally.

  10. Transcriptional Profiling of Type II Toxin-Antitoxin Genes of Helicobacter pylori under Different Environmental Conditions: Identification of HP0967-HP0968 System.

    PubMed

    Cárdenas-Mondragón, María G; Ares, Miguel A; Panunzi, Leonardo G; Pacheco, Sabino; Camorlinga-Ponce, Margarita; Girón, Jorge A; Torres, Javier; De la Cruz, Miguel A

    2016-01-01

    Helicobacter pylori is a Gram-negative bacterium that colonizes the human gastric mucosa and is responsible for causing peptic ulcers and gastric carcinoma. The expression of virulence factors allows the persistence of H. pylori in the stomach, which results in a chronic, sometimes uncontrolled inflammatory response. Type II toxin-antitoxin (TA) systems have emerged as important virulence factors in many pathogenic bacteria. Three type II TA systems have previously been identified in the genome of H. pylori 26695: HP0315-HP0316, HP0892-HP0893, and HP0894-HP0895. Here we characterized a heretofore undescribed type II TA system in H. pylori, HP0967-HP0968, which is encoded by the bicistronic operon hp0968-hp0967 and belongs to the Vap family. The predicted HP0967 protein is a toxin with ribonuclease activity whereas HP0968 is an antitoxin that binds to its own regulatory region. We found that all type II TA systems were expressed in H. pylori during early stationary growth phase, and differentially expressed in the presence of urea, nickel, and iron, although, the hp0968-hp0967 pair was the most affected under these environmental conditions. Transcription of hp0968-hp0967 was strongly induced in a mature H. pylori biofilm and when the bacteria interacted with AGS epithelial cells. Kanamycin and chloramphenicol considerably boosted transcription levels of all the four type II TA systems. The hp0968-hp0967 TA system was the most frequent among 317 H. pylori strains isolated from all over the world. This study is the first report on the transcription of type II TA genes in H. pylori under different environmental conditions. Our data show that the HP0967 and HP0968 proteins constitute a bona fide type II TA system in H. pylori, whose expression is regulated by environmental cues, which are relevant in the context of infection of the human gastric mucosa.

  11. The h-p Version of the Finite Element Method.

    DTIC Science & Technology

    1985-07-01

    NUMEERS r. Institute for Physical Science and Technology University of Maryland P College Park, MD 20742 ItI. CONTROLLING OFFICE NAMEC AND ADDRESS Is...commerical code (released in 1985) using the p and h-p versions. The h-p version combines the h and p-versions. The p-version was first theoretically studied ...satisfied 121 L1]- We will study the approximation (in the space H1 ) of functions u B2 ,d 2) by the h-p version and will show that exponential rate

  12. Enhanced durability and reactivity for zinc ferrite desulfurization sorbent

    SciTech Connect

    Jha, M.C.; Baltich, L.K.

    1987-02-23

    AMAX Research Development Center (AMAX R D) has been investigating methods for enhancing the reactivity and durability of the zinc ferrite desulfurization sorbent. Zinc ferrite sorbents are intended for use in desulfurization of hot coal gas in integrated gasification combined cycle (IGCC) or molten carbonate fuel cell (MCFC) applications. For the present program, the reactivity of the sorbent may be defined as its sulfur sorption capacity at the breakthrough point and at saturation in a bench-scale, fixed-bed reactor. Durability may be defined as the ability of the sorbent to maintain important physical characteristics such As size, strength, and specific surface area during 10 cycles of sulfidation and oxidation.

  13. Enhanced durability and reactivity for zinc ferrite desulfurization sorbent

    SciTech Connect

    Silaban, A.; Harrison, D.P. . Dept. of Chemical Engineering)

    1989-05-02

    AMAX Research Development Center (AMAX R D) has been investigating methods for enhancing the reactivity and durability of the zinc ferrite desulfurization sorbent. Zinc ferrite sorbents are intended for use in desulfurization of hot coal gas in integrated gasification combined cycle (IGCC) or molten carbonate fuel cell (MCFC) applications. For the present program, the reactivity of the sorbent may be defined as its sulfur sorption capacity at the breakthrough point and at saturation in a bench-scale, fixed-bed reactor. Durability may be defined as the ability of the sorbent to maintain important physical characteristics such as size, strength, and specific surface area during 10 cycles of sulfidation and oxidation.

  14. Enhanced durability and reactivity for zinc ferrite desulfurization sorbent

    SciTech Connect

    Jha, M.C.; Berggren, M.H.

    1989-05-02

    AMAX Research Development Center (AMAX R D) has been investigating methods for enhancing the reactivity and durability of the zinc ferrite desulfurization sorbent. Zinc ferrite sorbents are intended for use in desulfurization of hot coal gas in integrated gasification combined cycle (IGCC) or molten carbonate fuel cell (MCFC) applications. For the present program, the reactivity of the sorbent may be defined as its sulfur sorption capacity at the breakthrough point and at saturation in a bench-scale, fixed-bed reactor. Durability may be defined as the ability of the sorbent to maintain important physical characteristics such As size, strength, and specific surface area during 10 cycles of sulfidation and oxidation.

  15. Control of thiosulfate in wet desulfurization process solutions

    SciTech Connect

    Castrantas, H.M.

    1983-01-04

    A method for controlling the concentration of dissolved thiosulfate byproduct which forms in a wet desulfurization process, by introducing a peroxygen chemical into its recirculating aqueous absorption medium. A peroxygen chemical such as aqueous hydrogen peroxide is introduced into the recirculating aqueous alkaline absorption medium, preferably after its regeneration, in an amount sufficient to maintain the concentration of thiosulfate byproduct below a saturation concentration. The method is applicable to cyclic wet desulfurization processes, used to recover elemental sulfur from H/sub 2/S-containing gas streams, in which the absorption medium contains a regenerable oxidizing agent and is subject to thiosulfate byproduct buildup.

  16. Desulfurization of coal by microbial column flotation.

    PubMed

    Ohmura, N; Saiki, H

    1994-06-05

    Twenty-three strains capable of oxidizing iron were isolated from coal and ore storage sites as well as coal and ore mines, volcanic areas, and hot spring. Four strains were found to have high iron-oxidizing activity. One strain (T-4) was selected for this experiment since the strain showed the fastest leaching rate of iron and sulfate from pyrite among the four strains. The T-4 strain was assigned for Thiobacillus ferrooxidans from its cultural and morphological characteristics.Bacterial treatment was applied to column flotation. An increase of cell density in the microbial column flotation resulted in the increase of pyrite removal from a coal-pyrite mixture (high sulfur imitated coal) with corresponding decrease of coal recovery. The addition of kerosene into the microbial column flotation increased the recovery of the imitated coal from 55% (without kerosene) to 81% (with 50 microL/L kerosene) with the reduction of pyrite sulfur content from 11% (feed coal) to 3.9% (product coal). The kerosene addition could reduce the pyritic sulfur content by collecting the coal in the recovery. However, the addition could not enhance separation of pyrite from the coal-pyrite mixture, since pyrite rejection was not affected by the increase of the kerosene addition. An excellent separation was obtained by the microbial flotation using a long column which had a length-diameter (L/D) ratio of 12.7. The long column flotation reduced the pyritic sulfur content from 11% (feed coal) to 1.8% (product coal) when 80% of the feed coal was recovered without the kerosene addition. The long column flotation not only attained an excellent separation but also reduced the amount of cells for desulfurization to as little as one-tenth of the reported amount.

  17. Flue gas desulfurization by rotating beds

    SciTech Connect

    Gardner, N.; Keyvani, M.; Coskundeniz, A.

    1992-01-01

    The operating and mass transfer characteristics of rotating foam metal beds were studied to determine the potential for flue gas desulfurization. This is a final technical report on the work supported by DOE [number sign]FG22-87-PC79924. The report is divided into two sections, Part 1 deals primarily with the operating characteristics of rotating beds, and Part 2 covers the mass transfer characteristics of S0[sub 2] absorption in water-lime slurries. Rotating foam metal beds are in essence packed towers operated in high gravitational fields. The foam metal bed is in the form of a cylindrical donut, or torus, and is rotated to produced the high centrifugal forces. The liquid phase enters the bed at the inner surface of the torus and is pulled by the field through the bed. Gas flows countercurrent to the liquid. The bed packing can have a very large specific surface areas and not flood. Possible benefits include much smaller height of a transfer unit resulting in smaller equipment and supporting structures, reduced solvent inventory, faster response with improved process control, reduced pressure drop, and shorter startup and shut-down times. This work is concerned broadly with the operating characteristics of rotating beds, the objectives being to (1) determine the pressure drop through the rotating bed; (2) determine the power required to operate the beds, (3) investigate the residence time distribution of the liquid phase in the beds; and (4) determine the mass transfer coefficients of S0[sub 2] absorption. Three packings of differing specific surface areas were studied, with areas ranging from 656 to 2952 m[sub 2]/m[sub 3]. Liquid flow rates to 36 kg/s*m[sub 2], gas flow rate to 2.2 kg/s*m[sub 2], and gravitational fields to 300 g were covered in this study.

  18. Chromatin Protein HP1α Interacts with the Mitotic Regulator Borealin Protein and Specifies the Centromere Localization of the Chromosomal Passenger Complex*

    PubMed Central

    Liu, Xing; Song, Zhenwei; Huo, Yuda; Zhang, Jiahai; Zhu, Tongge; Wang, Jianyu; Zhao, Xuannv; Aikhionbare, Felix; Zhang, Jiancun; Duan, Hequan; Wu, Jihui; Dou, Zhen; Shi, Yunyu; Yao, Xuebiao

    2014-01-01

    Accurate mitosis requires the chromosomal passenger protein complex (CPC) containing Aurora B kinase, borealin, INCENP, and survivin, which orchestrates chromosome dynamics. However, the chromatin factors that specify the CPC to the centromere remain elusive. Here we show that borealin interacts directly with heterochromatin protein 1α (HP1α) and that this interaction is mediated by an evolutionarily conserved PXVXL motif in the C-terminal borealin with the chromo shadow domain of HP1α. This borealin-HP1α interaction recruits the CPC to the centromere and governs an activation of Aurora B kinase judged by phosphorylation of Ser-7 in CENP-A, a substrate of Aurora B. Consistently, modulation of the motif PXVXL leads to defects in CPC centromere targeting and aberrant Aurora B activity. On the other hand, the localization of the CPC in the midzone is independent of the borealin-HP1α interaction, demonstrating the spatial requirement of HP1α in CPC localization to the centromere. These findings reveal a previously unrecognized but direct link between HP1α and CPC localization in the centromere and illustrate the critical role of borealin-HP1α interaction in orchestrating an accurate cell division. PMID:24917673

  19. Tonopah Test Range EGS graphics tracking display system: HP370

    SciTech Connect

    Meyer, R.H.; Bauhs, K.C.

    1994-08-01

    This report describes the HP370 component of the Enhanced Graphics System (EGS) used at Tonopah Test Range (TTR). Selected Radar data is fed into the computer systems and the resulting tracking symbols are displayed on high-resolution video monitors in real time. These tracking symbols overlay background maps and are used for monitoring/controlling various flight vehicles. This report discusses both the operational aspects and the internal configuration of the HP370 Workstation portion of the EGS system.

  20. ENGINEERING EVALUATION OF HOT-GAS DESULFURIZATION WITH SULFUR RECOVERY

    SciTech Connect

    G.W. ROBERTS; J.W. PORTZER; S.C. KOZUP; S.K. GANGWAL

    1998-05-31

    Engineering evaluations and economic comparisons of two hot-gas desulfurization (HGD) processes with elemental sulfur recovery, being developed by Research Triangle Institute, are presented. In the first process, known as the Direct Sulfur Recovery Process (DSRP), the SO{sub 2} tail gas from air regeneration of zinc-based HGD sorbent is catalytically reduced to elemental sulfur with high selectivity using a small slipstream of coal gas. DSRP is a highly efficient first-generation process, promising sulfur recoveries as high as 99% in a single reaction stage. In the second process, known as the Advanced Hot Gas Process (AHGP), the zinc-based HGD sorbent is modified with iron so that the iron portion of the sorbent can be regenerated using SO{sub 2} . This is followed by air regeneration to fully regenerate the sorbent and provide the required SO{sub 2} for iron regeneration. This second-generation process uses less coal gas than DSRP. Commercial embodiments of both processes were developed. Process simulations with mass and energy balances were conducted using ASPEN Plus. Results show that AHGP is a more complex process to operate and may require more labor cost than the DSRP. Also capital costs for the AHGP are higher than those for the DSRP. However, annual operating costs for the AHGP appear to be considerably less than those for the DSRP with a potential break-even point between the two processes after just 2 years of operation for an integrated gasification combined cycle (IGCC) power plant using 3 to 5 wt% sulfur coal. Thus, despite its complexity, the potential savings with the AHGP encourage further development and scaleup of this advanced process.

  1. A fiber optics system for monitoring utilization of ZnO adsorbent beds during desulfurization for logistic fuel cell applications

    NASA Astrophysics Data System (ADS)

    Sujan, Achintya; Yang, Hongyun; Dimick, Paul; Tatarchuk, Bruce J.

    2016-05-01

    An in-situ fiber optic based technique for direct measurement of capacity utilization of ZnO adsorbent beds by monitoring bed color changes during desulfurization for fuel cell systems is presented. Adsorbents composed of bulk metal oxides (ZnO) and supported metal oxides (ZnO/SiO2 and Cusbnd ZnO/SiO2) for H2S removal at 22 °C are examined. Adsorbent bed utilization at breakthrough is determined by the optical sensor as the maximum derivative of area under UV-vis spectrum from 250 to 800 nm observed as a function of service time. Since the response time of the sensor due to bed color change is close to bed breakthrough time, a series of probes along the bed predicts utilization of the portion of bed prior to H2S breakthrough. The efficacy of the optical sensor is evaluated as a function of inlet H2S concentration, H2S flow rate and desulfurization in presence of CO, CO2 and moisture in feed. A 6 mm optical probe is employed to measure utilization of a 3/16 inch ZnO extrudate bed for H2S removal. It is envisioned that with the application of the optical sensor, desulfurization can be carried out at high adsorbent utilization and low operational costs during on-board miniaturized fuel processing for logistic fuel cell power systems.

  2. Bench-scale demonstration of hot-gas desulfurization technology. Quarterly report, October 1 - December 31, 1995

    SciTech Connect

    1995-12-31

    The US Department of Energy (DOE) Morgantown Energy Technology Center (METC) is sponsoring research in advanced methods for controlling contaminants in hot coal gasifier gas (coal gas) streams of integrated gasification combined-cycle (IGCC) power systems. The programs focus on hot-gas particulate removal and desulfurization technologies that match or nearly match the temperatures and pressures of the gasifier, cleanup system, and power generator. The work seeks to eliminate the need for expensive heat recovery equipment, reduce efficiency losses due to quenching, and minimize wastewater treatment costs. The goal of this project is to continue further development of the zinc titanate desulfurization and direct sulfur recovery process (DSRP) technologies by (1) scaling up the zinc titanate reactor system; (2) developing an integrated skid-mounted zinc titanate desulfurization-DSRP reactor system; (3) testing the integrated system over an extended period with real coal-gas from an operating gasifier to quantify the degradative effect, if any, of the trace contaminants present in coal gas; (4) developing an engineering database suitable for system scaleup; and (5) designing, fabricating and commissioning a larger DSRP reactor system capable of operating on a six-fold greater volume of gas than the DSRP reactor used in the bench-scale field test. The work performed during the October 1 through December 31, 1995 is described.

  3. Kinetics of Mn-based sorbents for hot coal gas desulfurization. Quarterly progress report, July 15, 1995--September 15, 1995

    SciTech Connect

    Hepworth, M.T.

    1995-09-15

    The Morgantown Energy Technology Center (METC) of the U.S. Department of Energy (DOE) is actively pursuing the development of reliable and cost-effective processes to clean coal gasifier gases for application to integrated gasification combined cycle (IGCC) and molten carbonate fuel cell (MCFC) power plants. A large portion of gas cleanup research has been directed towards hot gas desulfurization using Zn-based sorbents. However, zinc titinate sorbents undergo reduction to the metal at temperatures approaching 700{degrees}C. In addition, sulfate formation during regeneration leads to spalling of reactive 293 surfaces. Due to zinc-based sorbent performance, METC has shown interest in formulating and testing manganese-based sorbents. Westmoreland and Harrison evaluated numerous candidate sulfur sorbents and identified Mn as a good candidate. Later, Turkdogan and Olsson tested manganese-based sorbents which demonstrated superior desulfurization capacity under high temperatures, and reducing conditions. Recently, Ben-Slimane and Hepworth conducted several studies on formulating Mn-sorbents and desulfurizing a simulated fuel gas. Although thermodynamics predicts higher over-pressures with Mn verses Zn, under certain operating conditions Mn-based sorbents may obtain < 20 ppmv. In addition, the manganese-sulfur-oxygen (Mn-S-O) system does not reduce to the metal under even highly reducing gases at high temperatures (550-900{degrees}C). Currently, many proposed IGCC processes include a water quench prior to desulfurization. This is for two reasons; limitations in the process hardware (1000{degrees}C), and excessive Zn-based sorbent loss (about 700{degrees}C). With manganese the water quench is obviated due to sorbent loss, as Mn-based sorbents have been shown to retain reactivity under cycling testing at 900{degrees}C. This reduces system hardware, and increases thermal efficiency while decreasing the equilibrium H{sub 2}S over-pressure obtainable with a manganese sorbent.

  4. Bench-scale demonstration of hot-gas desulfurization technology. Quarterly report, October 1 - December 31, 1994

    SciTech Connect

    1994-12-31

    The U.S. Department of Energy (DOE), Morgantown Energy Technology Center (METC), is sponsoring research in advanced methods for controlling contaminants in hot coal gasifier gas (coal gas) streams of integrated gasification combined-cycle (IGCC) power systems. The programs focus on hot-gas particulate removal and desulfurization technologies that match or nearly match the temperatures and pressures of the gasifier, cleanup system, and power generator. The work seeks to eliminate the need for expensive heat recovery equipment, reduce efficiency losses due to quenching, and minimize wastewater treatment costs. Hot-gas desulfurization research has focused on regenerable mixed-metal oxide sorbents which can reduce the sulfur in coal gas to less than 20 ppmv and can be regenerated in a cyclic manner with air for multicycle operation. Zinc titanate (Zn{sub 2}TiO{sub 4} or ZnTiO{sub 3}), formed by a solid-state reaction of zinc (ZnO) and titanium dioxide (TiO{sub 2}), is currently one of the leading sorbents. This report summarizes the highlights and accomplishments of the October slipstream test run of the Zinc Titanate Fluid Bed Desulfurization/Direct Sulfur Recovery Process (ZTFBD/DSRP) Mobile Laboratory at the Department of Energy`s Morgantown Energy Technology Center. Although the run had to be shortened due to mechanical problems with METC`s gasifier, there was sufficient on-stream time to demonstrate highly successful operation of both the zinc titanate fluid bed desulfurization and the DSRP with actual coal gas.

  5. IHI in-line type flue gas desulfurization system

    SciTech Connect

    Yamaguchi, F.; Kanamori, A.; Fujino, Y.

    1995-06-01

    Desulfurization systems are indispensable for reducing air pollution caused by flue gas from power plants. It is essential that the cost for constructing and operating such systems is low. IHI has developed such a system based on its expertise gathered over the years. The test results and outline of the system are presented in this paper.

  6. Effect of Flue Gas Desulfurization Waste on Corn Plants

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Flue gas desulfurization gypsum (FGDG) is a by-product of conversion of sulfur dioxide into solid waste from coal combustion power generation plant. This by-product is rich in calcium, magnesium, and contains various other essential plant nutrients. The beneficial use of application of this waste as...

  7. FLUE GAS DESULFURIZATION: THE STATE OF THE ART

    EPA Science Inventory

    The paper gives results of a review of commercially available flue gas desulfurization (FGD) technologies that have an established record of full-scale performance. (NOTE: Sulfur dioxide (SO2) scrubbers may be used by coal-fired electrcity generating units to meet the requiremen...

  8. CURRENT STATUS OF ADVACATE PROCESS FOR FLUE GAS DESULFURIZATION

    EPA Science Inventory

    The following report discusses current bench- and pilot-plant advances in preparation of ADVAnced siliCATE (ADVACATE) calcium silicate sorbentsfor flue gas desulfurization. It also discusses current bench- and pilot-plant advances in sorbent preparation. Fly ash was ground in a l...

  9. Core-in-shell sorbent for hot coal gas desulfurization

    DOEpatents

    Wheelock, Thomas D.; Akiti, Jr., Tetteh T.

    2004-02-10

    A core-in-shell sorbent is described herein. The core is reactive to the compounds of interest, and is preferably calcium-based, such as limestone for hot gas desulfurization. The shell is a porous protective layer, preferably inert, which allows the reactive core to remove the desired compounds while maintaining the desired physical characteristics to withstand the conditions of use.

  10. Workshop on sulfur chemistry in flue gas desulfurization

    SciTech Connect

    Wallace, W.E. Jr.

    1980-05-01

    The Flue Gas Desulfurization Workshop was held at Morgantown, West Virginia, June 7-8, 1979. The presentations dealt with the chemistry of sulfur and calcium compounds in scrubbers. DOE and EPRI programs in this area are described. Ten papers have been entered individually into EDB and ERA. (LTN)

  11. Fluorescent signaling of oxone by desulfurization of thioamide.

    PubMed

    Eor, Suyoung; Hwang, Jiyoung; Choi, Myung Gil; Chang, Suk-Kyu

    2011-02-04

    The chemosignaling of the oxidant Oxone by selective desulfurization of a thioamide was investigated. Pyrene-thioamide was efficiently converted to its amide analogue by reaction with Oxone, resulting in a pronounced fluorescent turn-on type signaling. Selective signaling of Oxone in aqueous solution was possible in the presence of representative alkali and alkaline earth metal ions, as well as common anions.

  12. Development of advanced hot-gas desulfurization processes

    SciTech Connect

    Jothimurugesan, K.

    1999-10-14

    Advanced integrated gasification combined cycle (IGCC) power plants nearing completion, such as Sierra-Pacific, employ a circulating fluidized-bed (transport) reactor hot-gas desulfurization (HGD) process that uses 70-180 {micro}m average particle size (aps) zinc-based mixed-metal oxide sorbent for removing H{sub 2}S from coal gas down to less than 20 ppmv. The sorbent undergoes cycles of absorption (sulfidation) and air regeneration. The key barrier issues associated with a fluidized-bed HGD process are chemical degradation, physical attrition, high regeneration light-off (initiation) temperature, and high cost of the sorbent. Another inherent complication in all air-regeneration-based HGD processes is the disposal of the problematic dilute SO{sub 2} containing regeneration tail-gas. Direct Sulfur Recovery Process (DSRP), a leading first generation technology, efficiently reduces this SO{sub 2} to desirable elemental sulfur, but requires the use of 1-3 % of the coal gas, thus resulting in an energy penalty to the plant. Advanced second-generation processes are under development that can reduce this energy penalty by modifying the sorbent so that it could be directly regenerated to elemental sulfur. The objective of this research is to support the near and long term DOE efforts to commercialize the IGCC-HGD process technology. Specifically we aim to develop: optimized low-cost sorbent materials with 70-80 {micro}m average aps meeting all Sierra specs; attrition resistant sorbents with 170 {micro}m aps that allow greater flexibility in the choice of the type of fluidized-bed reactor e.g. they allow increased throughput in a bubbling-bed reactor; and modified fluidizable sorbent materials that can be regenerated to produce elemental sulfur directly with minimal or no use of coal gas The effort during the reporting period has been devoted to development of an advanced hot-gas process that can eliminate the problematic SO{sub 2} tail gas and yield elemental sulfur

  13. Development of advanced hot-gas desulfurization processes

    SciTech Connect

    Jothimurugesan, K.

    1999-04-26

    Advanced integrated gasification combined cycle (IGCC) power plants nearing completion, such as Sierra-Pacific, employ a circulating fluidized-bed (transport) reactor hot-gas desulfurization (HGD) process that uses 70-180 {micro}m average particle size (aps) zinc-based mixed-metal oxide sorbent for removing H{sub 2}S from coal gas down to less than 20 ppmv. The sorbent undergoes cycles of absorption (sulfidation) and air regeneration. The key barrier issues associated with a fluidized-bed HGD process are chemical degradation, physical attrition, high regeneration light-off (initiation) temperature, and high cost of the sorbent. Another inherent complication in all air-regeneration-based HGD processes is the disposal of the problematic dilute SO{sub 2} containing regeneration tail-gas. Direct Sulfur Recovery Process (DSRP), a leading first generation technology, efficiently reduces this SO{sub 2} to desirable elemental sulfur, but requires the use of 1-3% of the coal gas, thus resulting in an energy penalty to the plant. Advanced second-generation processes are under development that can reduce this energy penalty by modifying the sorbent so that it could be directly regenerated to elemental sulfur. The objective of this research is to support the near and long term DOE efforts to commercialize the IGCC-HGD process technology. Specifically we aim to develop: optimized low-cost sorbent materials with 70-80 {micro}m average aps meeting all Sierra specs; attrition resistant sorbents with 170 {micro}m aps that allow greater flexibility in the choice of the type of fluidized-bed reactor e.g. they allow increased throughput in a bubbling-bed reactor; and modified fluidizable sorbent materials that can be regenerated to produce elemental sulfur directly with minimal or no use of coal gas. The effort during the reporting period has been devoted to development of optimized low-cost zinc-oxide-based sorbents for Sierra-Pacific. The sorbent surface were modified to prevent

  14. Effect of operating parameters and reactor structure on moderate temperature dry desulfurization

    SciTech Connect

    Jie Zhang; Changfu You; Haiying Qi; Bo Hou; Changhe Chen; Xuchang Xu

    2006-07-01

    A moderate temperature dry desulfurization process at 600-800 C was studied in a pilot-scale circulating fluidized bed flue gas desulfurization (CFB-FGD) experimental facility. The desulfurization efficiency was investigated for various operating parameters. Structural improvements in key parts of the CFB-FGD system, i.e., the cyclone separator and the distributor, were made to improve the desulfurization efficiency and flow resistance. The experimental results show that the desulfurization efficiency increased rapidly with increasing temperature above 600 C due to enhanced gas diffusion and the shift of the equilibrium for the carbonate reaction. The sorbent sulfated gradually after quick carbonation of the sorbent with a long particle residence time necessary to realize a high desulfurization ratio. A reduced solids concentration in the bed reduced the particle residence time and the desulfurization efficiency. A single-stage cyclone separator produced no improvement in the desulfurization efficiency compared with a two-stage cyclone separator. Compared with a wind cap distributor, a large hole distributor reduced the flow resistance which reduced the desulfurization efficiency due to the reduced bed pressure drop and worsened bed fluidization. The desulfurization efficiency can be improved by increasing the collection efficiency of fine particles to prolong their residence time and by improving the solids concentration distribution to increase the gas-solid contact surface area. 16 refs., 9 figs.

  15. Effect of operating parameters and reactor structure on moderate temperature dry desulfurization.

    PubMed

    Zhang, Jie; You, Changfu; Qi, Haiying; Hou, Bo; Chen, Changhe; Xu, Xuchang

    2006-07-01

    A moderate temperature dry desulfurization process at 600-800 degrees C was studied in a pilot-scale circulating fluidized bed flue gas desulfurization (CFB-FGD) experimental facility. The desulfurization efficiency was investigated for various operating parameters, such as bed temperature, CO2 concentration, and solids concentration. In addition, structural improvements in key parts of the CFB-FGD system, i.e., the cyclone separator and the distributor, were made to improve the desulfurization efficiency and flow resistance. The experimental results show that the desulfurization efficiency increased rapidly with increasing temperature above 600 degrees C due to enhanced gas diffusion and the shift of the equilibrium for the carbonate reaction. The sorbent sulfated gradually after quick carbonation of the sorbent with a long particle residence time necessary to realize a high desulfurization ratio. A reduced solids concentration in the bed reduced the particle residence time and the desulfurization efficiency. A single-stage cyclone separator produced no improvement in the desulfurization efficiency compared with a two-stage cyclone separator. Compared with a wind cap distributor, a large hole distributor reduced the flow resistance which reduced the desulfurization efficiency due to the reduced bed pressure drop and worsened bed fluidization. The desulfurization efficiency can be improved by increasing the collection efficiency of fine particles to prolong their residence time and by improving the solids concentration distribution to increase the gas-solid contact surface area.

  16. Effect of surface attractive strength on structural transitions of a confined HP lattice protein

    NASA Astrophysics Data System (ADS)

    Pattanasiri, Busara; Li, Ying Wai; Wust, Thomas; Landau, David P.

    2015-09-01

    We investigate the influence of surface attractive strength on structural transitions of a hydrophobic-polar (HP) lattice protein confined in a slit formed by two parallel, attractive walls. We apply Wang-Landau sampling together with efficient Monte Carlo updates to estimate the density of states of the system. The conformational transitions, namely, the debridging process and hydrophobic core formation, can be identified by analyzing the specific heat together with several structural observables, such as the numbers of surface contacts, the number of hydrophobic pairs, and radii of gyration in different directions. As temperature decreases, we find that the occurrence of the debridging process is conditional depending on the surface attractive strength. This, in turn, affects the nature of the hydrophobic core formation that takes place at a lower temperature. We illustrate these observations with the aid of a HP protein chain with 48 monomers.

  17. Effect of surface attractive strength on structural transitions of a confined HP lattice protein

    SciTech Connect

    Pattanasiri, Busara; Li, Ying Wai; Wuest, Thomas; Landau, David P

    2015-01-01

    We investigate the influence of surface attractive strength on structural transitions of a hydrophobic-polar (HP) lattice protein confined in a slit formed by two parallel, attractive walls. We apply Wang-Landau sampling together with efficient Monte Carlo updates to estimate the density of states of the system. The conformational transitions, namely, the debridging process and hydrophobic core formation, can be identified by analyzing the specific heat together with several structural observables, such as the numbers of surface contacts, the number of hydrophobic pairs, and radii of gyration in different directions. As temperature decreases, we find that the occurrence of the debridging process is conditional depending on the surface attractive strength. This, in turn, affects the nature of the hydrophobic core formation that takes place at a lower temperature. We illustrate these observations with the aid of a HP protein chain with 48 monomers.

  18. Development of a hot-gas desulfurization system for IGCC applications

    SciTech Connect

    Gupta, R.; McMichael, W.J.; Gangwal, S.K.; Jain, S.C.; Dorchak, T.P.

    1992-12-31

    Integrated gasification combined cycle (IGCC) power plants are being advanced worldwide to produce electricity from coal because of their superior environmental performance, economics, and efficiency in comparison to conventional coal-based power plants. One key component of an advanced IGCC power plant is a hot-gas desulfurization system employing regenerable sorbents. To carry out hot-gas desulfurization in a fluidized-bed reactor, it is necessary that the sorbents have high attrition resistance, while still maintaining high chemical reactivity and sulfur absorption capacity. Also, efficient processes are needed for the treatment of SO{sub 2}-containing regeneration off-gas to produce environmentally benign waste or useful byproducts. A series of durable zinc titanate sorbents were formulated and tested in a bench-scale fluidized-bed reactor system. Reactive sorbents were developed with addition resistance comparable to fluid-bed cracking (FCC) catalysts used in petroleum refineries. In addition, progress continues on the development of the Direct Sulfur Recovery Process (DSRP) for converting SO{sub 2} in the regeneration off-gas to elemental sulfur. Plans are under way to test these bench-scale systems at gasifier sites with coal gas. This paper describes the status and future plans for the demonstration of these technologies.

  19. DEEP DESULFURIZATION OF DIESEL FUELS BY A NOVEL INTEGRATED APPROACH

    SciTech Connect

    Xiaoliang Ma; Michael Sprague; Lu Sun; Chunshan Song

    2002-10-01

    In order to reduce the sulfur level in liquid hydrocarbon fuels for environmental protection and fuel cell applications, deep desulfurization of a model diesel fuel and a real diesel fuel was conducted by our SARS (selective adsorption for removing sulfur) process using the adsorbent A-2. Effect of temperature on the desulfurization process was examined. Adsorption desulfurization at ambient temperature, 24 h{sup -1} of LHSV over A-2 is efficient to remove dibenzothiophene (DBT) in the model diesel fuel, but difficult to remove 4-methyldibenzothiophene (4-MDBT) and 4,6-dimethyl-dibenzothiophene (4,6-DMDBT). Adsorption desulfurization at 150 C over A-2 can efficiently remove DBT, 4-MDBT and 4,6-DMDBT in the model diesel fuel. The sulfur content in the model diesel fuel can be reduced to less than 1 ppmw at 150 C without using hydrogen gas. The adsorption capacity corresponding to the break-through point is 6.9 milligram of sulfur per gram of A-2 (mg-S/g-A-2), and the saturate capacity is 13.7 mg-S/g-A-2. Adsorption desulfurization of a commercial diesel fuel with a total sulfur level of 47 ppmw was also performed at ambient temperature and 24 h{sup -1} of LHSV over the adsorbent A-2. The results show that only part of the sulfur compounds existing in the low sulfur diesel can be removed by adsorption over A-2 at such operating conditions, because (1) the all sulfur compounds in the low sulfur diesel are the refractory sulfur compounds that have one or two alkyl groups at the 4- and/or 6-positions of DBT, which inhibit the approach of the sulfur atom to the adsorption site; (2) some compounds coexisting in the commercial low sulfur diesel probably inhibit the interaction between the sulfur compounds and the adsorbent. Further work in determining the optimum operating conditions and screening better adsorbent is desired.

  20. Desulfurization ability of refining slag with medium basicity

    NASA Astrophysics Data System (ADS)

    Yu, Hui-xiang; Wang, Xin-hua; Wang, Mao; Wang, Wan-jun

    2014-12-01

    The desulfurization ability of refining slag with relative lower basicity ( B) and Al2O3 content ( B = 3.5-5.0; 20wt%-25wt% Al2O3) was studied. Firstly, the component activities and sulfide capacity ( C S) of the slag were calculated. Then slag-metal equilibrium experiments were carried out to measure the equilibrium sulfur distribution ( L S). Based on the laboratorial experiments, slag composition was optimized for a better desulfurization ability, which was verified by industrial trials in a steel plant. The obtained results indicated that an MgO-saturated CaO-Al2O3-SiO2-MgO system with the basicity of about 3.5-5.0 and the Al2O3 content in the range of 20wt%-25wt% has high activity of CaO ( a CaO), with no deterioration of C S compared with conventional desulfurization slag. The measured L S between high-strength low-alloyed (HSLA) steel and slag with a basicity of about 3.5 and an Al2O3 content of about 20wt% and between HSLA steel and slag with a basicity of about 5.0 and an Al2O3 content of about 25wt% is 350 and 275, respectively. The new slag with a basicity of about 3.5-5.0 and an Al2O3 content of about 20wt% has strong desulfurization ability. In particular, the key for high-efficiency desulfurization is to keep oxygen potential in the reaction system as low as possible, which was also verified by industrial trials.

  1. Development of advanced hot-gas desulfurization processes

    SciTech Connect

    Jothimurugesan, K.

    2000-04-17

    Advanced integrated gasification combined cycle (IGCC) power plants nearing completion, such as Sierra-Pacific, employ a circulating fluidized-bed (transport) reactor hot-gas desulfurization (HGD) process that uses 70-180 {micro}m average particle size (aps) zinc-based mixed-metal oxide sorbent for removing H{sub 2}S from coal gas down to less than 20 ppmv. The sorbent undergoes cycles of absorption (sulfidation) and air regeneration. The key barrier issues associated with a fluidized-bed HGD process are chemical degradation, physical attrition, high regeneration light-off (initiation) temperature, and high cost of the sorbent. Another inherent complication in all air-regeneration-based HGD processes is the disposal of the problematic dilute SO{sub 2} containing regeneration tail-gas. Direct Sulfur Recovery Process (DSRP), a leading first generation technology, efficiently reduces this SO{sub 2} to desirable elemental sulfur, but requires the use of 1-3 % of the coal gas, thus resulting in an energy penalty to the plant. Advanced second-generation processes are under development that can reduce this energy penalty by modifying the sorbent so that it could be directly regenerated to elemental sulfur. The objective of this research is to support the near and long term DOE efforts to commercialize the IGCC-HGD process technology. Specifically we aim to develop: optimized low-cost sorbent materials with 70-80 {micro}m average aps meeting all Sierra specs; attrition resistant sorbents with 170 {micro}m aps that allow greater flexibility in the choice of the type of fluidized-bed reactor e.g. they allow increased throughput in a bubbling-bed reactor; and modified fluidizable sorbent materials that can be regenerated to produce elemental sulfur directly with minimal or no use of coal gas. The effort during the reporting period has been devoted to testing the FHR-32 sorbent. FHR-32 sorbent was tested for 50 cycles of sulfidation in a laboratory scale reactor.

  2. Petrographical records of multiple fluid-infiltration during HP-LT metamorphism (Invited)

    NASA Astrophysics Data System (ADS)

    Tsujimori, T.

    2013-12-01

    lawsonitite-bearing thermal regime, and subsequently a Cr-rich fluid infiltrated from ultramafic protoliths into the lawsonitite, probably along microfractures, and crystallized Cr-rich jadeite. Except for fluid-inclusion studies, direct tracking of subduction-zone aqueous fluids is not simple. However, syn-metamorphic crack-seal HP-LT mineral veins and peculiar metasomatic rocks such as lawsonitite have a great potential for decoding the origin and history of subduction-zone fluids. These petrographical records should certainly narrow down the critical targets of in-situ geochemistry in the exploration of fluid in fossil slabs.

  3. Electron beam inspection of 16nm HP node EUV masks

    NASA Astrophysics Data System (ADS)

    Shimomura, Takeya; Narukawa, Shogo; Abe, Tsukasa; Takikawa, Tadahiko; Hayashi, Naoya; Wang, Fei; Ma, Long; Lin, Chia-Wen; Zhao, Yan; Kuan, Chiyan; Jau, Jack

    2012-11-01

    EUV lithography (EUVL) is the most promising solution for 16nm HP node semiconductor device manufacturing and beyond. The fabrication of defect free EUV mask is one of the most challenging roadblocks to insert EUVL into high volume manufacturing (HVM). To fabricate and assure the defect free EUV masks, electron beam inspection (EBI) tool will be likely the necessary tool since optical mask inspection systems using 193nm and 199nm light are reaching a practical resolution limit around 16nm HP node EUV mask. For production use of EBI, several challenges and potential issues are expected. Firstly, required defect detection sensitivity is quite high. According to ITRS roadmap updated in 2011, the smallest defect size needed to detect is about 18nm for 15nm NAND Flash HP node EUV mask. Secondly, small pixel size is likely required to obtain the high sensitivity. Thus, it might damage Ru capped Mo/Si multilayer due to accumulated high density electron beam bombardments. It also has potential of elevation of nuisance defects and reduction of throughput. These challenges must be solved before inserting EBI system into EUV mask HVM line. In this paper, we share our initial inspection results for 16nm HP node EUV mask (64nm HP absorber pattern on the EUV mask) using an EBI system eXplore® 5400 developed by Hermes Microvision, Inc. (HMI). In particularly, defect detection sensitivity, inspectability and damage to EUV mask were assessed. As conclusions, we found that the EBI system has capability to capture 16nm defects on 64nm absorber pattern EUV mask, satisfying the sensitivity requirement of 15nm NAND Flash HP node EUV mask. Furthermore, we confirmed there is no significant damage to susceptible Ru capped Mo/Si multilayer. We also identified that low throughput and high nuisance defect rate are critical challenges needed to address for the 16nm HP node EUV mask inspection. The high nuisance defect rate could be generated by poor LWR and stitching errors during EB writing

  4. DEEP DESULFURIZATION OF DIESEL FUELS BY A NOVEL INTEGRATED APPROACH

    SciTech Connect

    Xiaoliang Ma; Uday Turaga; Shingo Watanabe; Subramani Velu; Chunshan Song

    2004-05-01

    The overall objective of this project is to explore a new desulfurization system concept, which consists of efficient separation of the refractory sulfur compounds from diesel fuel by selective adsorption, and effective hydrodesulfurization of the concentrated fraction of the refractory sulfur compounds in diesel fuels. Our approaches focused on (1) selecting and developing new adsorbents for selective adsorption of sulfur or sulfur compounds in commercial diesel fuel; (2) conducting the adsorption desulfurization of model fuels and real diesel fuels by the selective-adsorption-for-removing-sulfur (PSUSARS) process over various developed adsorbents, and examining the adsorptive desulfurization performance of various adsorbents; (3) developing and evaluating the regeneration methods for various spent adsorbent; (4) developing new catalysts for hydrodesulfurization of the refractory sulfur existing in the commercial diesel fuel; (5) on the basis of the fundamental understanding of the adsorptive performance and regeneration natures of the adsorbents, further confirming and improving the conceptual design of the novel PSU-SARS process for deep desulfurization of diesel fuel Three types of adsorbents, the metal-chloride-based adsorbents, the activated nickel-based adsorbents and the metal-sulfide-based adsorbents, have been developed for selective adsorption desulfurization of liquid hydrocarbons. All of three types of the adsorbents exhibit the significant selectivity for sulfur compounds, including alkyl dibenzothiophenes (DBTs), in diesel fuel. Adsorption desulfurization of real diesel fuels (regular diesel fuel (DF), S: 325 ppmw; low sulfur diesel fuel (LSD-I), S: 47 ppmw) over the nickel-based adsorbents (A-2 and A-5) has been conducted at different conditions by using a flowing system. The adsorption capacity of DF over A-2 corresponding to an outlet sulfur level of 30 ppmw is 2.8 mg-S/g-A. The adsorption capacity of LSD-I over A-5 corresponding to the break

  5. Analysis of Flue Gas Desulfurization (FGD) Processes for Potential Use on Army Coal-Fired Boilers

    DTIC Science & Technology

    1980-09-01

    TECHNICAL REPORT N-93 September 1980 ANALYSIS OF FLUE GAS DESULFURIZATION (FGD) PROCESSES FOR POTENTIAL USE ON ARMY COAL-FIRED BOILERS TECHNICAL LIBRARY...REFERENCE: Technical Report N-93, Analysis of Flue Gas Desulfurization (FGD) Ppooesses for Potential Use on Army Coal-Fired Boilers Please take a few...REPORT DOCUMENTATION PAGE 1. REPORT NUMBER CERL-TR-N-93 2. GOVT ACCESSION NO «. TITLE (end Subtitle) ANALYSIS OF FLUE GAS DESULFURIZATION (FGD

  6. Effect of Single-Site Mutations on HP Lattice Proteins

    SciTech Connect

    Shi, Guangjie; Vogel, Thomas; Wuest, Thomas; Li, Ying Wai; Landau, David P

    2014-01-01

    We developed a heuristic method for determining the ground-state degeneracy of hydrophobic-polar (HP) lattice proteins, based on Wang-Landau and multicanonical sampling. It is applied during comprehensive studies of single-site mutations in specific HP proteins with different sequences. The effects in which we are interested include structural changes in ground-states, changes of ground-state energy, degeneracy, and thermodynamic properties of the system. With respect to mutations, both extremely sensitive and insensitive positions in the HP sequence have been found. That is, ground state energies and degeneracies, as well as other thermodynamic and structural quantities may be either largely unaffected or may change significantly due to mutation.

  7. Design of an advanced 500-HP helicopter transmission

    NASA Technical Reports Server (NTRS)

    Braddock, C. E.

    1982-01-01

    A 500-hp Advanced Technology Demonstrator helicopter transmission was designed by an American aerospace company under a NASA contract. The project was mainly concerned with designing a 500-hp version of the OH-58C 317-hp transmission which would have the capabilities for a long, quiet life at a minimum increase in cost, weight, and space, which usually increase along with power increases. This objective was accomplished by implementing advanced technology which has been developed during the last decade and by making improvements dictated by field experience. The improvements are related to bearings made of cleaner gear steels, spiral bevel gears made of cleaner gear steels, high contact ratio spur gear teeth in the planetary which will reduce noise level and increase gear life, and modifications concerning the sun gear.

  8. Unraveling heavy oil desulfurization chemistry: targeting clean fuels.

    PubMed

    Choudhary, Tushar V; Parrott, Stephen; Johnson, Byron

    2008-03-15

    The sulfur removal chemistry of heavy oils has been unraveled by systematically investigating several heavy oils with an extremely wide range of properties. The heavy oil feed and product properties have been characterized by advanced analytical methods, and these properties have been related to the sulfur conversion data observed in pilot hydrotreating units. These studies coupled with kinetic treatment of the data have revealed that the desulfurization chemistry of heavy oils is essentially controlled by the strongly inhibiting three and larger ring aromatic hydrocarbon content and surprisingly not by the content of the "hard-to-remove" sulfur compounds. Such enhanced understanding of the heavy oil sulfur removal is expected to open new avenues for catalyst/process optimization for heavy oil desulfurization and thereby assist the efficent production of clean transporation fuels.

  9. Development of advanced hot-gas desulfurization sorbents. Final report

    SciTech Connect

    Jothimurugesan, K.; Adeyiga, A.A.; Gangwal, S.K.

    1997-10-01

    The objective of this project was to develop hot-gas desulfurization sorbent formulations for relatively lower temperature application, with emphasis on the temperature range from 343--538 C. The candidate sorbents include highly dispersed mixed metal oxides of zinc, iron, copper, cobalt, nickel and molybdenum. The specific objective was to develop suitable sorbents, that would have high and stable surface area and are sufficiently reactive and regenerable at the relatively lower temperatures of interest in this work. Stability of surface area during regeneration was achieved by adding stabilizers. To prevent sulfation, catalyst additives that promote the light-off of the regeneration reaction at lower temperature was considered. Another objective of this study was to develop attrition-resistant advanced hot-gas desulfurization sorbents which show stable and high sulfidation reactivity at 343 to 538 C and regenerability at lower temperatures than leading first generation sorbents.

  10. Exploring the Mechanism of Biocatalyst Inhibition in Microbial Desulfurization

    PubMed Central

    Abin-Fuentes, Andres; Mohamed, Magdy El-Said; Wang, Daniel I. C.

    2013-01-01

    Microbial desulfurization, or biodesulfurization (BDS), of fuels is a promising technology because it can desulfurize compounds that are recalcitrant to the current standard technology in the oil industry. One of the obstacles to the commercialization of BDS is the reduction in biocatalyst activity concomitant with the accumulation of the end product, 2-hydroxybiphenyl (HBP), during the process. BDS experiments were performed by incubating Rhodococcus erythropolis IGTS8 resting-cell suspensions with hexadecane at 0.50 (vol/vol) containing 10 mM dibenzothiophene. The resin Dowex Optipore SD-2 was added to the BDS experiments at resin concentrations of 0, 10, or 50 g resin/liter total volume. The HBP concentration within the cytoplasm was estimated to decrease from 1,100 to 260 μM with increasing resin concentration. Despite this finding, productivity did not increase with the resin concentration. This led us to focus on the susceptibility of the desulfurization enzymes toward HBP. Dose-response experiments were performed to identify major inhibitory interactions in the most common BDS pathway, the 4S pathway. HBP was responsible for three of the four major inhibitory interactions identified. The concentrations of HBP that led to a 50% reduction in the enzymes' activities (IC50s) for DszA, DszB, and DszC were measured to be 60 ± 5 μM, 110 ± 10 μM, and 50 ± 5 μM, respectively. The fact that the IC50s for HBP are all significantly lower than the cytoplasmic HBP concentration suggests that the inhibition of the desulfurization enzymes by HBP is responsible for the observed reduction in biocatalyst activity concomitant with HBP generation. PMID:24096431

  11. Numerical simulation of flow in the wet scrubber for desulfurization

    NASA Astrophysics Data System (ADS)

    Novosád, Jan; Vít, Tomáš

    2015-05-01

    This article deals with numerical simulation of flow and chemical reactions in absorber for desulfurization of flue-gas. The objective of the work is the investigation of effect of different nozzles types and their placement in spray layers. These nozzles distribute lime suspension into flue gas stream. The research includes two types of nozzles and four different arrangements of nozzles and spray layers. Conclusion describes the effect of nozzle types and their arrangements on the suspension concentration in absorber.

  12. Unusual chemical compounds in flue gas desulfurization systems

    SciTech Connect

    Dille, E.R.

    1996-08-01

    Flue gas desulfurization (FGD) systems continue to have deposits formed on internal surfaces of the materials of which the FGD systems are fabricated. These compounds contribute to crevice corrosion of the alloys of which some of the FGD systems are made. In the process of performing the failure analysis of the FGD fabrication materials, new compounds were discovered. This paper discusses two corrosion failure analysis case histories and the new compounds that were discovered and the chemical environment in which they were discovered.

  13. A methodology to split the total cumulative Hp(10) dose into the Hp(10) i doses received during various procedures performed by interventional cardiologist.

    PubMed

    Domienik, Joanna

    2017-03-01

    The methodology describing how to split the cumulative Hp(10) dose of interventional cardiologists into Hp(10) i doses received during procedures of various types based on procedure-specific ELDO coefficients and Hp(3) doses per procedure is presented. The appropriate equations for Hp(10) i (Hp(10) for procedure type i), depending on the number of various procedure types (i  =  1 … 4) performed by a particular physician, are derived. The methodology can be applied to whole-body doses measured on the lead apron and therefore can be used for optimisation of work practices in those catheterisation labs where routine dosimeter is worn above the apron.

  14. Transcriptional Profiling of Type II Toxin–Antitoxin Genes of Helicobacter pylori under Different Environmental Conditions: Identification of HP0967–HP0968 System

    PubMed Central

    Cárdenas-Mondragón, María G.; Ares, Miguel A.; Panunzi, Leonardo G.; Pacheco, Sabino; Camorlinga-Ponce, Margarita; Girón, Jorge A.; Torres, Javier; De la Cruz, Miguel A.

    2016-01-01

    Helicobacter pylori is a Gram-negative bacterium that colonizes the human gastric mucosa and is responsible for causing peptic ulcers and gastric carcinoma. The expression of virulence factors allows the persistence of H. pylori in the stomach, which results in a chronic, sometimes uncontrolled inflammatory response. Type II toxin–antitoxin (TA) systems have emerged as important virulence factors in many pathogenic bacteria. Three type II TA systems have previously been identified in the genome of H. pylori 26695: HP0315–HP0316, HP0892–HP0893, and HP0894–HP0895. Here we characterized a heretofore undescribed type II TA system in H. pylori, HP0967–HP0968, which is encoded by the bicistronic operon hp0968–hp0967 and belongs to the Vap family. The predicted HP0967 protein is a toxin with ribonuclease activity whereas HP0968 is an antitoxin that binds to its own regulatory region. We found that all type II TA systems were expressed in H. pylori during early stationary growth phase, and differentially expressed in the presence of urea, nickel, and iron, although, the hp0968–hp0967 pair was the most affected under these environmental conditions. Transcription of hp0968–hp0967 was strongly induced in a mature H. pylori biofilm and when the bacteria interacted with AGS epithelial cells. Kanamycin and chloramphenicol considerably boosted transcription levels of all the four type II TA systems. The hp0968–hp0967 TA system was the most frequent among 317 H. pylori strains isolated from all over the world. This study is the first report on the transcription of type II TA genes in H. pylori under different environmental conditions. Our data show that the HP0967 and HP0968 proteins constitute a bona fide type II TA system in H. pylori, whose expression is regulated by environmental cues, which are relevant in the context of infection of the human gastric mucosa. PMID:27920769

  15. The mechanism of coal gas desulfurization by iron oxide sorbents.

    PubMed

    Lin, Yi-Hsing; Chen, Yen-Chiao; Chu, Hsin

    2015-02-01

    This study aims to understand the roles of hydrogen and carbon monoxide during the desulfurization process in a coal gasification system that H2S of the syngas was removed by Fe2O3/SiO2 sorbents. The Fe2O3/SiO2 sorbents were prepared by incipient wetness impregnation. Through the breakthrough experiments and Fourier transform infrared spectroscopy analyses, the overall desulfurization mechanism of the Fe2O3/SiO2 sorbents was proposed in this study. The results show that the major reaction route is that Fe2O3 reacts with H2S to form FeS, and the existence of CO and H2 in the simulated gas significantly affects equilibrium concentrations of H2S and COS. The formation of COS occurs when the feeding gas is blended with CO and H2S, or CO2 and H2S. The pathways in the formation of products from the desulfurization process by the reaction of Fe2O3 with H2S have been successfully established.

  16. Molecular biological enhancement of coal desulfurization. Final report

    SciTech Connect

    Krawiec, S.

    1994-12-31

    During the period from 1986 through 1993 the prospect of bacterial desulfurization of fossil fuel was transformed from a theoretically appealing concept to a demonstrable laboratory phenomenon. Results from several laboratories confirmed that there was not one but, rather, several metabolic bases of selectively removing sulfur from the carbon frame of sulfur-containing organic compounds characteristic of fossil fuels. Results in this report relate solely to the so-called ``4S`` pathway (named for the four sulfur-containing compounds in the sequence: (l) dibenzothiophene [DBT] {yields} (2) dibenzothiophene sulfoxide [DBTO] {yields} (3) dibenzosulfone [DBTO{sup 2}] {yields} (4) dibenzosulfonate {yields} monohydroxybiphenyl [OH-BP] + SO{sub 4}{sup =}. [An additional desulfurized product, biphenyl, has been hypothesized and another, o,o{prime}-biphenyl, observed.]) The following subjects are discussed: isolating bacteria with a DbtS{sup +} phenotype; confirming the production of a desulfurized product; determining the identity of the isolates; determining the growth characteristics of the isolates in batch and continuous cultures; determining the kinetics and yields of product in batch and continuous cultures.

  17. Human Hp1-1 and Hp2-2 Phenotype-Specific Haptoglobin Therapeutics Are Both Effective In Vitro and in Guinea Pigs to Attenuate Hemoglobin Toxicity

    PubMed Central

    Lipiski, Miriam; Deuel, Jeremy W.; Baek, Jin Hyen; Engelsberger, Wolfgang R.

    2013-01-01

    Abstract Aims: Infusion of purified haptoglobin (Hp) functions as an effective hemoglobin (Hb) scavenging therapeutic in animal models of hemolysis to prevent cardiovascular and renal injury. Epidemiologic studies demonstrate the phenotype heterogeneity of human Hp proteins and suggest differing vascular protective potential imparted by the dimeric Hp1-1 and the polymeric Hp2-2. Results: In vitro experiments and in vivo studies in guinea pigs were performed to evaluate phenotype-specific differences in Hp therapeutics. We found no differences between the two phenotypes in Hb binding and intravascular compartmentalization of Hb in vivo. Both Hp1-1 and Hp2-2 attenuate Hb-induced blood pressure response and renal iron deposition. These findings were consistent with equal prevention of Hb endothelial translocation. The modulation of oxidative Hb reactions by the two Hp phenotypes was not found to be different. Both phenotypes stabilize the ferryl (Fe4+) Hb transition state, provide heme retention within the complex, and prevent Hb-driven low-density lipoprotein (LDL) peroxidation. Hb-mediated peroxidation of LDL resulted in endothelial toxicity, which was equally blocked by the addition of Hp1-1 and Hp2-2. Innovation and Conclusion: The present data do not provide support for the concept that phenotype-specific Hp therapeutics offer differential efficacy in mitigating acute Hb toxicity. Antioxid. Redox Signal. 19, 1619–1633. PMID:23418677

  18. Use of Flue Gas Desulfurization (FGD) Gypsum as a Heavy Metal Stabilizer in Contaminated Soils

    EPA Science Inventory

    Flue Gas Desulfurization (FGD) gypsum is a synthetic by-product generated from the flue gas desulfurization process in coal power plants. It has several beneficial applications such as an ingredient in cement production, wallboard production and in agricultural practice as a soil...

  19. Genetic screening for modifiers of the DREF pathway in Drosophila melanogaster: identification and characterization of HP6 as a novel target of DREF

    PubMed Central

    Ida, Hiroyuki; Suzusho, Noriyuki; Suyari, Osamu; Yoshida, Hideki; Ohno, Katsuhito; Hirose, Fumiko; Itoh, Masanobu; Yamaguchi, Masamitsu

    2009-01-01

    The DNA replication-related element-binding factor (DREF) regulates cell proliferation-related gene expression in Drosophila. By genetic screening, taking advantage of the rough eye phenotype of transgenic flies that express DREF in the eye discs, we identified 24 genes that suppressed and 12 genes that enhanced the rough eye phenotype when heterozygous for mutations. Five genes, HP6, pigeon, lace, X box binding protein 1 and guftagu were found to carry replication-related element (DRE) sequences in their 5′-flanking regions. Of these, the HP6 gene carries two sequences that match seven out of eight nucleotides of DRE and two additional sequences that match six out of eight nucleotides of DRE in the 5′-flanking region. Band mobility shift assays using Drosophila Kc cell nuclear extracts demonstrated DREF binding to two of these sites and chromatin immunoprecipitation using anti-DREF antibodies confirmed that this occurs in vivo. Knockdown of DREF in Drosophila S2 cells decreased the HP6 mRNA level. The results, taken together, indicate that DREF directly regulates expression of the HP6 gene. HP6 mRNA was detected throughout development by RT-PCR with highest levels in adult males. In addition, immunostaining analyses revealed colocalization of HP6 and DREF in nuclei at the apical tips in the testes. PMID:19136464

  20. Genetic screening for modifiers of the DREF pathway in Drosophila melanogaster: identification and characterization of HP6 as a novel target of DREF.

    PubMed

    Ida, Hiroyuki; Suzusho, Noriyuki; Suyari, Osamu; Yoshida, Hideki; Ohno, Katsuhito; Hirose, Fumiko; Itoh, Masanobu; Yamaguchi, Masamitsu

    2009-04-01

    The DNA replication-related element-binding factor (DREF) regulates cell proliferation-related gene expression in Drosophila. By genetic screening, taking advantage of the rough eye phenotype of transgenic flies that express DREF in the eye discs, we identified 24 genes that suppressed and 12 genes that enhanced the rough eye phenotype when heterozygous for mutations. Five genes, HP6, pigeon, lace, X box binding protein 1 and guftagu were found to carry replication-related element (DRE) sequences in their 5'-flanking regions. Of these, the HP6 gene carries two sequences that match seven out of eight nucleotides of DRE and two additional sequences that match six out of eight nucleotides of DRE in the 5'-flanking region. Band mobility shift assays using Drosophila Kc cell nuclear extracts demonstrated DREF binding to two of these sites and chromatin immunoprecipitation using anti-DREF antibodies confirmed that this occurs in vivo. Knockdown of DREF in Drosophila S2 cells decreased the HP6 mRNA level. The results, taken together, indicate that DREF directly regulates expression of the HP6 gene. HP6 mRNA was detected throughout development by RT-PCR with highest levels in adult males. In addition, immunostaining analyses revealed colocalization of HP6 and DREF in nuclei at the apical tips in the testes.

  1. 78 FR 48468 - Hewlett Packard Company, Hewlett Packard Enterprise Business Unit, EG HP Storage, Enterprise...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-08

    ... Employment and Training Administration Hewlett Packard Company, Hewlett Packard Enterprise Business Unit, EG HP Storage, Enterprise Storage, Servers and Networking Storage, APP Management, Research and... behalf of workers of Hewlett Packard Company, Hewlett Packard Enterprise Business Unit, EG HP...

  2. Evidences for CYP3A4 autoactivation in the desulfuration of dimethoate by the human liver.

    PubMed

    Buratti, Franca M; Testai, Emanuela

    2007-11-20

    Dimethoate (DIM) is an organophosphorothionate (OPT) pesticide used worldwide as a systemic insecticide and acaricide. It is characterized by low-to-moderate acute mammalian toxicity; similarly to the other OPT pesticides, its mode of action is mediated by the inhibition of acetylcholinesterase (AChE), exerted by its toxic metabolite dimethoate-oxon or omethoate (OME), which is also used as a direct acting pesticide. Human hepatic DIM bioactivation to the toxic metabolite OME has been characterized by using c-DNA expressed human CYPs and human liver microsomes (HLM) also in the presence of CYP-specific chemical inhibitors, with a method based on AChE inhibition. The obtained kinetic parameters and AChE IC(50) have been compared with those previously obtained with other OPTs, indicating a lower efficiency in DIM desulfuration reaction and a lower potency in inhibiting AChE. Results showed that, similarly to the other OPTs tested so far, at low DIM concentration OME formation is mainly catalysed by CYP1A2, while the role of 3A4 is relevant at high DIM levels. Differently from the other OPTs, DIM desulfuration reaction showed an atypical kinetic profile, likely due to CYP3A4 autoactivation. The sigmoidicity degree of the activity curve increased with the level of CYP3A4 in HLM or disappeared in the presence of a CYP3A4 chemical inhibitor. This atypical kinetic behaviour can be considered one of the possible explanations for the recent findings that among patients hospitalized following OPT intoxication, DIM ingestion gave different symptoms and more severe poisoning (23.1% of fatal cases versus total) than chlorpyrifos (8% of deaths), which has a lower LD(50) value. Since DIM-poisoned patients poorly responded to pralidoxime, the possibility to use CYP3A4 inhibitors could be considered as a complementary treatment.

  3. Bench-scale demonstration of hot-gas desulfurization technology. Quarterly technical progress report, October 1--December 31, 1993

    SciTech Connect

    Not Available

    1994-04-01

    Research Triangle Institute (RTI) with DOE/METC sponsorship has been developing zinc titanate sorbent technology since 1986. In addition, RTI has been developing the Direct Sulfur Recovery Process (DSRP) with DOE/METC sponsorship since 1988. Fluidized-bed zinc titanate desulfurization coupled to the DSRP is currently the most advanced and attractive technology for sulfur removal/recovery for IGCC systems, and it has recently been proposed in a Clean Coal Technology project. The goal of this project is to continue further development of the zinc titanate desulfurization and DSRP technologies by: scaling up the zinc titanate reactor system; developing an integrated skid-mounted zinc titanate desulfurization-DSRP reactor system; testing the integrated system over an extended period with real coal-gas from an operating gasifier to quantify the degradative effect, if any, of the trace contaminants present in coal gas; developing an engineering database suitable for system scaleup; and designing, fabricating and commissioning a larger DSRP reactor system capable of operating on a six-fold greater volume of gas than the DSRP reactor used in the bench-scale field test. During this reporting period the Construction Permit Application was completed and approved by the Process Safety Committee, and a final revised Application has been submitted to DOE/METC. A draft Test Plan for the field test was formulated. Finally, progress was made in the reactor system fabrication with the submission of purchase orders for nearly all major equipment, and with the final design of the trailer (mobile laboratory).

  4. Adsorption of HP Lattice Proteins on Patterned Surfaces

    NASA Astrophysics Data System (ADS)

    Wilson, Matthew; Shi, Guangjie; Landau, David P.; Li, Ying Wai; Wuest, Thomas

    2014-03-01

    The HP lattice model[2] is a course-grained, yet useful tool for modeling protein sequences where amino acids are treated as either hydrophobic (H) or polar (P) monomers. With the use of Wang-Landau sampling and an efficient set of Monte-Carlo moves[3], HP lattice proteins adsorbed on patterned surfaces are studied. Each substrate is modeled as a periodically bounded pattern of lattice sites that interact with either H or P monomers in the lattice protein, where the energy contributions of the surface are determined by assigned coupling strengths. By analyzing energy degeneracies, along with the thermodynamic and structural quantities of the protein, both the protein folding and surface adsorption can be observed. The adsorption behavior of the lattice proteins on patterned surfaces will be compared to those interacting with uniform surfaces. Research supported by NSF.

  5. Performance modeling of Arabian asphalt using HP-GPC

    NASA Astrophysics Data System (ADS)

    Asi, I. M.; Wahhab, H. I. Al-Abdul; Al-Dubabi, I. A.; Ali, M. F.

    1997-08-01

    In this study, Arabian neat asphalt samples were collected from different asphalt producing refineries in the Gulf countries. Another set of polymer modified samples was also included in this study. In the polymer modification process, 5,10, and 15% crumb rubber (CRT) and 3,6, and 9% styrene-butadiene-styrene (SBS) were used. All asphalt samples were subjected to two aging processes to simulate heating, mixing, compaction, and in-service aging. The asphalt samples at the different aging stages were subjected to performance-based tests that were adapted and/or modified by the Strategic Highway Research Program (SHRP) team. High pressure gel permeation chromatography (HP-GPC) was used to chemically analyze the test samples by generating profiles of their molecular size distribution. Models were built to predict the performance-based properties from the produced HP-GPC profiles.

  6. Maintenance of HP 5071A Primary Frequency Standards at USNO

    DTIC Science & Technology

    1997-12-01

    29th Annual Precise Time and Time Interual (PTTI) Meeting MAINTENANCE OF HP 5071A PRIMARY FREQUENCY STANDARDS USNO AT H. Chadsey (hc...planck.usno.navy.mil A. Kubik (tony@ simon.usno.navy.rni1) Time Service Department U.S. Naval Observatory Washington, D.C. 20392 Abstract The US. Naval...show any correlation of them with the time , frequency, and environmental changes. This paper will also ofet some indicators to predict future device

  7. Molecular biological enhancement of coal desulfurization. Final report

    SciTech Connect

    Krawiec, S.

    1995-01-01

    Fresh isolates of bacteria presumptively identified as R. erythropolis unequivocally have a DbtS{sup +} phenotype. The production of OH-BP from either DBT or DBTO{sub 2} was confirmed by difference spectroscopy, HPLC, and mass spectrometry. The temperature, pH, and means of supplying the thiophenic or sulfonic sole source of sulfur were optimized. The maximal rate of growth of the organism, its affinity for sulfone, and the extent to which substrate was converted to product were determined by using batch, fed batch, and continuous cultures. For strain N1-36, the maximum specific growth rate was 0.235 hr{sup -1} which corresponds to a minimal generation time of 2.95 hr. The K{sub s} was estimated to be 0.39 {mu}M. With 100 {mu}M DBT as the sole sulfur source, approximately 40 {mu}M OH-BP are produced (after 40 hr of growth); with 100 {mu}M DBTO{sub 2} as the sole sulfur source, approximately 70 {mu}M OH-BP are produced (after 40 hr of growth). The desulfurization activity is repressed by SO{sub 4}{sup =} OH-BP does not serve as a carbon source. The DbtS{sup +} phenotype of the R. erythropolis isolates is stable and discrete. The isolates selectively remove sulfur from DBT, a compound which models a refractory form of organic sulfur in compounds characteristic of fossil fuels. The desulfurization occurs with no oxidation of carbon-carbon bonds. The stability and specificity (along with genetic regulation) indicate that microbial desulfurization in a real phenomenon in which a noxious element is removed without significantly affecting the calorific value of the substrate. Additional characterization (and optimization) would provide the basis of a very important form of fossil fuel beneficiation.

  8. Hot-Gas Desulfurization with Sulfur Recovery

    SciTech Connect

    Portzer, Jeffrey W.; Damle, Ashok S.; Gangwal, Santosh K.

    1997-07-01

    The objective of this study is to develop a second generation HGD process that regenerates the sulfided sorbent directly to elemental sulfur using SO{sub 2}, with minimal consumption of coal gas. The goal is to have better overall economics than DSRP when integrated with the overall IGCC system.

  9. Exploring HP protein models using Wang-Landau sampling

    NASA Astrophysics Data System (ADS)

    Wuest, Thomas; Landau, David P.

    2008-03-01

    The hydrophobic-polar (HP) protein model has become a standard in assessing the efficiency of computational methods for protein structure prediction as well as for exploring the statistical physics of protein folding in general. Numerous methods have been proposed to address the challenges of finding minimal energy conformations within the rough energy landscape of this lattice heteropolymer model. However, only a few studies have been dedicated to the more revealing - but also more demanding - problem of estimating the density of states which allows access to thermodynamic properties of a system at any temperature. Here, we show that Wang-Landau sampling, in connection with a suitable move set (``pull moves''), provides a powerful route for the ground state search and the precise determination of the density of states for HP sequences (with up to 100 monomers) in both, two and three dimensions. Our procedure possesses an intrinsic simplicity and overcomes the inevitable limitations inherent in other more tailored approaches. The main advantage lies in its general applicability to a broad range of lattice protein models that go beyond the scope of the HP model.

  10. The 3600 hp split-torque helicopter transmission

    NASA Technical Reports Server (NTRS)

    White, G.

    1985-01-01

    Final design details of a helicopter transmission that is powered by GE twin T 700 engines each rated at 1800 hp are presented. It is demonstrated that in comparison with conventional helicopter transmission arrangements the split torque design offers: weight reduction of 15%; reduction in drive train losses of 9%; and improved reliability resulting from redundant drive paths between the two engines and the main shaft. The transmission fits within the NASA LeRC 3000 hp Test Stand and accepts the existing positions for engine inputs, main shaft, connecting drive shafts, and the cradle attachment points. One necessary change to the test stand involved gear trains of different ratio in the tail drive gearbox. Progressive uprating of engine input power from 3600 to 4500 hp twin engine rating is allowed for in the design. In this way the test transmission will provide a base for several years of analytical, research, and component development effort targeted at improving the performance and reliability of helicopter transmission.

  11. Methods, systems, and devices for deep desulfurization of fuel gases

    DOEpatents

    Li, Liyu [Richland, WA; King, David L [Richland, WA; Liu, Jun [Richland, WA; Huo, Qisheng [Richland, WA

    2012-04-17

    A highly effective and regenerable method, system and device that enables the desulfurization of warm fuel gases by passing these warm gasses over metal-based sorbents arranged in a mesoporous substrate. This technology will protect Fischer-Tropsch synthesis catalysts and other sulfur sensitive catalysts, without drastic cooling of the fuel gases. This invention can be utilized in a process either alone or alongside other separation processes, and allows the total sulfur in such a gas to be reduced to less than 500 ppb and in some instances as low as 50 ppb.

  12. Cost effective materials for flue gas desulfurization (FGD)

    SciTech Connect

    Kelley, D.H.; Brady, B.

    1996-10-01

    Wet Flue Gas Desulfurization (FGD) is an effective way to remove sulfur dioxide from coal combustion processes and reduce the potential for acid rain. However, wet FGD processes often require highly corrosion resistant construction materials such as high alloys for adequate service life. An excellent material for wet FGD applications at about one half the cost of high alloys is fiberglass-reinforced plastic (FRP) based on epoxy vinyl ester resin. This paper discusses the background and improvements that have led to the use of some of the world`s largest composite structures in FGD service.

  13. Spray tower: the workhorse of flue-gas desulfurization

    SciTech Connect

    Saleem, A.

    1980-10-01

    A recently developed spray tower system for use in a utility flue gas desulfurization system is simple, durable, and capable of achieving very high sulfur dioxide removal efficiencies, possibly approaching 100%. The principles behind the design and operation of the spray tower are discussed. The quality of water used for washing, tower size limitations, construction materials liquid distribution, gas-inlet design, gas distribution, mass transfer, and operating characteristics are examined. Procedures to maintain the reliability and high performance of the spray tower are described. (5 diagrams, 5 photos, 12 references, 1 table)

  14. Synthesis of Neoglycoconjugates by the Desulfurative Rearrangement of Allylic Disulfides

    PubMed Central

    Crich, David; Yang, Fan

    2009-01-01

    Two series of neoglucosyl donors are prepared based on connection of the allylic disulfide motif to the anomeric center via either a simple O-glycosyl linkage or N-glycosyl amide unit. Conjugation of both sets of donors to cysteine in peptides is demonstrated through classical disulfide exchange followed by the phosphine-mediated desulfurative allylic rearrangement resulting in neoglycopeptides characterized by a simple thioether spacer. The conjugation reaction functions in the absence of protecting groups on both the neoglycosyl donor and peptide in aqueous media at room temperature. PMID:18729514

  15. Desulfurization Of Gas-Turbine Blades

    NASA Technical Reports Server (NTRS)

    Outlaw, Ronald A.

    1994-01-01

    Sulfur removed from nickel-base superalloy used to make gas-turbine blades by heating alloy and simultaneously subjecting it to sputtering by directed Ar(Sup+) ions from ion gun or from glow discharge. Reduction of sulfur content of superalloy by factor of 10 increases lifetime of turbine blade made of alloy by similar factor, because stability of protective surface oxide formed during operation of turbine increased.

  16. Helicobacter pylori CheZ(HP) and ChePep form a novel chemotaxis-regulatory complex distinct from the core chemotaxis signaling proteins and the flagellar motor.

    PubMed

    Lertsethtakarn, Paphavee; Howitt, Michael R; Castellon, Juan; Amieva, Manuel R; Ottemann, Karen M

    2015-09-01

    Chemotaxis is important for Helicobacter pylori to colonize the stomach. Like other bacteria, H. pylori uses chemoreceptors and conserved chemotaxis proteins to phosphorylate the flagellar rotational response regulator, CheY, and modulate the flagellar rotational direction. Phosphorylated CheY is returned to its non-phosphorylated state by phosphatases such as CheZ. In previously studied cases, chemotaxis phosphatases localize to the cellular poles by interactions with either the CheA chemotaxis kinase or flagellar motor proteins. We report here that the H. pylori CheZ, CheZ(HP), localizes to the poles independently of the flagellar motor, CheA, and all typical chemotaxis proteins. Instead, CheZ(HP) localization depends on the chemotaxis regulatory protein ChePep, and reciprocally, ChePep requires CheZ(HP) for its polar localization. We furthermore show that these proteins interact directly. Functional domain mapping of CheZ(HP) determined the polar localization motif lies within the central domain of the protein and that the protein has regions outside of the active site that participate in chemotaxis. Our results suggest that CheZ(HP) and ChePep form a distinct complex. These results therefore suggest the intriguing idea that some phosphatases localize independently of the other chemotaxis and motility proteins, possibly to confer unique regulation on these proteins' activities.

  17. Enhanced desulfurizing flotation of coal using sonoelectrochemical method.

    PubMed

    Zhang, Hong-Xi; Hou, Xiao-Yang; Xu, Shi-Xun; Li, Zhi-Long; Yu, Hai-Feng; Shen, Xue-Hua

    2013-09-01

    Enhanced desulfurizing flotation of low sulfur coal was investigated using sonoelectrochemical method. The supporting electrolyte used in this process was sodium chloride and the additive was anhydrous ethanol. The effects of treatment conditions on desulfurization were studied by a single-factor method. The conditions include anhydrous ethanol concentration, sodium chloride concentration, sonoelectrolytic voltage, sonoelectrolytic temperature, sonoelectrolytic time and coal sample granulometry. The optimal experimental conditions achieved for anhydrous ethanol concentration, sodium chloride concentration, sonoelectrolytic voltage, sonoelectrolytic temperature and sonoelectrolytic time are 1.7 mol L(-1), 5.1×10(-3) mol L(-1), 10 V, 70 °C, 50 min achieved for a -0.18 mm coal sample. Optimal conditions cause a sulfur reduction of up to 69.4%. The raw and treated coals were analyzed by infrared spectroscopy and a chemical method. Pyritic sulfur, organic sulfur, ash as well as moisture are partially removed. The combination of high sulfur reduction, high yield, as well as high ash reduction was obtained in the newly developed method of enhanced flotation by sonoelectrochemistry. Ultrasound irradiation promotes electron transfer efficiency and increases clean coal yield.

  18. Anion-exchange resin-based desulfurization process

    SciTech Connect

    Sheth, A.C.; Strevel, S.D.; Dharmapurikar, R.

    1992-01-01

    Under the current grant, the University of Tennessee Space Institute (UTSI) will carry out the bench scale evaluation and further development of the anion-exchange resin-based desulfurization concept to desulfurize alkali metal sulfates. This concept has been developed and patented by UTSI under US Patent No. 4,917,874. The developmental program proposed under this DOE grant includes screening of commercially available resins to select three candidate resins for further study. These three resins will undergo a series of experiments designed to test the resins' performance under different process conditions (including the use of spent MHD seed material). The best of these resins will be used in optimizing the regeneration step and in testing the effects of performance enhancers. The process schematic developed from the results will be used to estimate the related economics. During this reporting period, October 1, 1991 to September 30, 1992, analysis of batch mode screening experiments was completed to select three candidate resins for process variables study in the fixed-bed set-up. This setup was modified and the experiments were carded out to evaluate effects of major process variables. The analysis of fixed-bed experiments is going on and we have also started simple batch mode experiments to identify desirable conditions for resin regeneration step. We have also started simple process engineering type calculations to determine the trade-off between the solution concentration and the resulting evaporation/concentration load.

  19. BENCH-SCALE DEMONSTRATION OF HOT-GAS DESULFURIZATION TECHNOLOGY

    SciTech Connect

    Unknown

    1999-07-01

    The U.S. Department of Energy (DOE), National Energy Technology Laboratory (NETL), is sponsoring research in advanced methods for controlling contaminants in hot coal gasifier gas (coal-derived fuel-gas) streams of integrated gasification combined-cycle (IGCC) power systems. The hot gas cleanup work seeks to eliminate the need for expensive heat recovery equipment, reduce efficiency losses due to quenching, and minimize wastewater treatment costs. Hot-gas desulfurization research has focused on regenerable mixed-metal oxide sorbents that can reduce the sulfur in coal-derived fuel-gas to less than 20 ppmv and can be regenerated in a cyclic manner with air for multicycle operation. Zinc titanate (Zn{sub 2}TiO{sub 4} or ZnTiO{sub 3}), formed by a solid-state reaction of zinc oxide (ZnO) and titanium dioxide (TiO{sub 2}), is currently one of the leading sorbents. Overall chemical reactions with Zn{sub 2}TiO{sub 4} during the desulfurization (sulfidation)-regeneration cycle are shown. The sulfidation/regeneration cycle can be carried out in a fixed-bed, moving-bed, or fluidized-bed reactor configuration. The fluidized-bed reactor configuration is most attractive because of several potential advantages including faster kinetics and the ability to handle the highly exothermic regeneration to produce a regeneration offgas containing a constant concentration of SO{sub 2}.

  20. BENCH-SCALE DEMONSTRATION OF HOT-GAS DESULFURIZATION TECHNOLOGY

    SciTech Connect

    Unknown

    2000-09-01

    The U.S. Department of Energy (DOE), National Energy Technology Laboratory (NETL), is sponsoring research in advanced methods for controlling contaminants in hot coal gasifier gas (coal-derived fuel-gas) streams of integrated gasification combined-cycle (IGCC) power systems. The hot gas cleanup work seeks to eliminate the need for expensive heat recovery equipment, reduce efficiency losses due to quenching, and minimize wastewater treatment costs. Hot-gas desulfurization research has focused on regenerable mixed-metal oxide sorbents that can reduce the sulfur in coal-derived fuel-gas to less than 20 ppmv and can be regenerated in a cyclic manner with air for multicycle operation. Zinc titanate (Zn{sub 2}TiO{sub 4} or ZnTiO{sub 3}), formed by a solid-state reaction of zinc oxide (ZnO) and titanium dioxide (TiO{sub 2}), is currently one of the leading sorbents. Overall chemical reactions with Zn{sub 2}TiO{sub 4} during the desulfurization (sulfidation)-regeneration cycle are shown. The sulfidation/regeneration cycle can be carried out in a fixed-bed, moving-bed, or fluidized-bed reactor configuration. The fluidized-bed reactor configuration is most attractive because of several potential advantages including faster kinetics and the ability to handle the highly exothermic regeneration to produce a regeneration offgas containing a constant concentration of SO{sub 2}.

  1. An experimental study on desulfurization of high-sulfur coal slime with free jet flotation column

    SciTech Connect

    Xie Hua; Huang Bo; Xia Qing

    1998-12-31

    A free jet flotation column gives good selectivity and high separation efficiency in treating fine and ultra-fine coal. This paper reports test results of coal desulfurization with a free jet flotation column. Test results showed that when the coal sample from Zhong Liang Shan was processed its pyritic sulfur content was reduced from 3.08% to 0.84%, with 72.22% recovery of combustible matter in clean coal. The concept of Desulfurization Efficiency Index E(ds) for a comprehensive evaluation of desulfurization process is proposed, which is defined as the product of the ratio of sulfur content reduction and the recovery of combustible matters in clean coal.

  2. Method for enhancing the desulfurization of hot coal gas in a fluid-bed coal gasifier

    DOEpatents

    Grindley, Thomas

    1989-01-01

    A process and apparatus for providing additional desulfurization of the hot gas produced in a fluid-bed coal gasifier, within the gasifier. A fluid-bed of iron oxide is located inside the gasifier above the gasification bed in a fluid-bed coal gasifier in which in-bed desulfurization by lime/limestone takes place. The product gases leave the gasification bed typically at 1600.degree. to 1800.degree. F. and are partially quenched with water to 1000.degree. to 1200.degree. F. before entering the iron oxide bed. The iron oxide bed provides additional desulfurization beyond that provided by the lime/limestone.

  3. Phosphorylation–dephosphorylation cycle of HP1α governs accurate mitotic progression

    PubMed Central

    Chakraborty, Arindam; Prasanth, Supriya G

    2014-01-01

    Heterochromatin protein 1α (HP1α), a bona fide factor of silent chromatin, is required for establishing as well as maintaining the higher-order chromatin structure in eukaryotes. HP1α is decorated with several post-translational modifications, and many of these are critical for its cellular functions. HP1α is heavily phosphorylated; however, its physiological relevance had remained to be completely understood. We have recently demonstrated that human HP1α is a mitotic target for NDR kinase, and the phosphorylation at the hinge region of HP1α at the G2/M phase of the cell cycle is crucial for mitotic progression and Sgo1 loading at mitotic centromeres (Chakraborty et al., 2014). We now demonstrate that the dephosphorylation of HP1α within its hinge domain occurs during mitosis, specifically soon after prometaphase. In the absence of the hinge-specific HP1α phosphorylation, either as a consequence of depleting NDR1 or in cells expressing a non-phosphorylatable HP1α mutant, the cells arrest in prometaphase with several mitotic defects. In this study we show that NDR1-depleted cells expressing hinge-specific phosphomimetic HP1α mutant rescues the prometaphase arrest but displays defects in mitotic exit, suggesting that the dephosphorylation of HP1α is required for the completion of cytokinesis. Taken together, our results reveal that the phosphorylation–dephosphorylation cycle of HP1α orchestrates accurate progression of cells through mitosis. PMID:24786771

  4. Gas cleaning and hydrogen sulfide removal for COREX coal gas by sorption enhanced catalytic oxidation over recyclable activated carbon desulfurizer.

    PubMed

    Sun, Tonghua; Shen, Yafei; Jia, Jinping

    2014-02-18

    This paper proposes a novel self-developed JTS-01 desulfurizer and JZC-80 alkaline adsorbent for H2S removal and gas cleaning of the COREX coal gas in small-scale and commercial desulfurizing devices. JTS-01 desulfurizer was loaded with metal oxide (i.e., ferric oxides) catalysts on the surface of activated carbons (AC), and the catalyst capacity was improved dramatically by means of ultrasonically assisted impregnation. Consequently, the sulfur saturation capacity and sulfur capacity breakthrough increased by 30.3% and 27.9%, respectively. The whole desulfurizing process combined selective adsorption with catalytic oxidation. Moreover, JZC-80 adsorbent can effectively remove impurities such as HCl, HF, HCN, and ash in the COREX coal gas, stabilizing the system pressure drop. The JTS-01 desulfurizer and JZC-80 adsorbent have been successfully applied for the COREX coal gas cleaning in the commercial plant at Baosteel, Shanghai. The sulfur capacity of JTS-01 desulfurizer can reach more than 50% in industrial applications. Compared with the conventional dry desulfurization process, the modified AC desulfurizers have more merit, especially in terms of the JTS-01 desulfurizer with higher sulfur capacity and low pressure drop. Thus, this sorption enhanced catalytic desulfurization has promising prospects for H2S removal and other gas cleaning.

  5. Perspectives on Industrial Innovation from Agilent, HP, and Bell Labs

    NASA Astrophysics Data System (ADS)

    Hollenhorst, James

    2014-03-01

    Innovation is the life blood of technology companies. I will give perspectives gleaned from a career in research and development at Bell Labs, HP Labs, and Agilent Labs, from the point of view of an individual contributor and a manager. Physicists bring a unique set of skills to the corporate environment, including a desire to understand the fundamentals, a solid foundation in physical principles, expertise in applied mathematics, and most importantly, an attitude: namely, that hard problems can be solved by breaking them into manageable pieces. In my experience, hiring managers in industry seldom explicitly search for physicists, but they want people with those skills.

  6. The 300 H.P. Benz Aircraft Engine

    NASA Technical Reports Server (NTRS)

    Heller, A

    1921-01-01

    A description is given of the Benz 12-cylinder aircraft engine. The 300 H.P. engine, with the cylinders placed at an angle of 60 degrees not only realizes a long-cherished conception, but has received refinement in detail. It may be described as a perfect example of modern German aircraft engine construction. Here, a detailed description is given of the construction of this engine. Emphasis is placed on the design and construction of the cylinders, pistons, and connecting rods. Also discussed are engine fitting, lubrication, oil pumps, bearings, the oil tank, fuel pump, carburetors, and cooling system.

  7. PULSION registered HP: Tunable, High Productivity Plasma Doping

    SciTech Connect

    Felch, S. B.; Torregrosa, F.; Etienne, H.; Spiegel, Y.; Roux, L.; Turnbaugh, D.

    2011-01-07

    Plasma doping has been explored for many implant applications for over two decades and is now being used in semiconductor manufacturing for two applications: DRAM polysilicon counter-doping and contact doping. The PULSION HP is a new plasma doping tool developed by Ion Beam Services for high-volume production that enables customer control of the dominant mechanism--deposition, implant, or etch. The key features of this tool are a proprietary, remote RF plasma source that enables a high density plasma with low chamber pressure, resulting in a wide process space, and special chamber and wafer electrode designs that optimize doping uniformity.

  8. Coal desulfurization in a rotary kiln combustor

    SciTech Connect

    Cobb, J.T. Jr.

    1992-09-11

    The purpose of this project was to demonstrate the combustion of coal and coal wastes in a rotary kiln reactor with limestone addition for sulfur control. The rationale for the project was the perception that rotary systems could bring several advantages to combustion of these fuels, and may thus offer an alternative to fluid-bed boilers. Towards this end, an existing wood pyrolysis kiln (the Humphrey Charcoal kiln) was to be suitably refurbished and retrofitted with a specially designed version of a patented air distributor provided by Universal Energy, Inc. (UEI). As the project progressed beyond the initial stages, a number of issues were raised regarding the feasibility and the possible advantages of burning coals in a rotary kiln combustor and, in particular, the suitability of the Humphrey Charcoal kiln as a combustor. Instead, an opportunity arose to conduct combustion tests in the PEDCO Rotary Cascading-Bed Boiler (RCBB) commercial demonstration unit at the North American Rayon CO. (NARCO) in Elizabethton, TN. The tests focused on anthracite culm and had two objectives: (a) determine the feasibility of burning anthracite culms in a rotary kiln boiler and (b) obtain input for any further work involving the Humphrey Charcoal kiln combustor. A number of tests were conducted at the PEDCO unit. The last one was conducted on anthracite culm procured directly from the feed bin of a commercial circulating fluid-bed boiler. The results were disappointing; it was difficult to maintain sustained combustion even when large quantities of supplemental fuel were used. Combustion efficiency was poor, around 60 percent. The results suggest that the rotary kiln boiler, as designed, is ill-suited with respect to low-grade, hard to burn solid fuels, such as anthracite culm. Indeed, data from combustion of bituminous coal in the PEDCO unit suggest that with respect to coal in general, the rotary kiln boiler appears inferior to the circulating fluid bed boiler.

  9. Shigella flexneri targets the HP1γ subcode through the phosphothreonine lyase OspF

    PubMed Central

    Harouz, Habiba; Rachez, Christophe; Meijer, Benoit M; Marteyn, Benoit; Donnadieu, Françoise; Cammas, Florence; Muchardt, Christian; Sansonetti, Philippe; Arbibe, Laurence

    2014-01-01

    HP1 proteins are transcriptional regulators that, like histones, are targets for post-translational modifications defining an HP1-mediated subcode. HP1γ has multiple phosphorylation sites, including serine 83 (S83) that marks it to sites of active transcription. In a guinea pig model for Shigella enterocolitis, we observed that the defective type III secretion mxiD Shigella flexneri strain caused more HP1γ phosphorylation in the colon than the wild-type strain. Shigella interferes with HP1 phosphorylation by injecting the phospholyase OspF. This effector interacts with HP1γ and alters its phosphorylation at S83 by inactivating ERK and consequently MSK1, a downstream kinase. MSK1 that here arises as a novel HP1γ kinase, phosphorylates HP1γ at S83 in the context of an MSK1-HP1γ complex, and thereby favors its accumulation on its target genes. Genome-wide transcriptome analysis reveals that this mechanism is linked to up-regulation of proliferative gene and fine-tuning of immune gene expression. Thus, in addition to histones, bacteria control host transcription by modulating the activity of HP1 proteins, with potential implications in transcriptional reprogramming at the mucosal barrier. PMID:25216677

  10. Synthesis and application of different phthalocyanine molecular sieve catalyst for oxidative desulfurization

    SciTech Connect

    Zhao, Na; Li, Siwen; Wang, Jinyi; Zhang, Ronglan; Gao, Ruimin; Zhao, Jianshe; Wang, Junlong

    2015-05-15

    M{sub 2}(PcAN){sub 2} (M=Fe, Co, Ni, Cu, Zn and Mn) anchored onto W-HZSM-5 (M{sub 2}(PcAN){sub 2}–W-HZSM-5) or the M{sub 2}(PcTN){sub 2} doping W-HZSM-5 (M{sub 2}(PcTN){sub 2}/W-HZSM-5) were prepared and their catalytic performances were tested for oxidative desulfurization in the presence of oxygen. Thiophene (T), benzothiophene (BT), and dibenzothiophene (DBT) were considered as sulfur compounds. Among zeolite-based catalysts, the Cu{sub 2}(PcAN){sub 2}–W-HZSM-5 and Cu{sub 2}(PcTN){sub 2}/W-HZSM-5 showed superior desulfurization performance and the activity of selectivity followed the order: T>BT>DBT. The effects of phthalocyanine concentration were studied by UV–Vis and calcination temperature was obtained by TG-DSC for Cu{sub 2}(PcTN){sub 2}/W-HZSM-5. Catalysts were characterized by EA, IR, XRD, SEM, TEM, ICP, and N{sub 2} adsorption. Reaction time, temperature and the amount of catalyst were investigated as the important parameters for optimization of the reaction. Furthermore, a possible process of oxidative desulfurization and the reaction products were proposed. - Graphical abstract: The ODS reaction schematic shows the reaction mechanism of ultra-deep desulfurization. The sulfur compounds are oxidized to their corresponding sulfoxides or sulfones through the use of oxygen and catalysts. The reaction process of ultra-deep desulfurization. - Highlights: • A kind of novel catalyst for deep desulfurization was synthesized. • Cu{sub 2}(PcAN){sub 2}–W-HZSM-5 exhibits excellent catalytic performance for desulfurization. • The reaction conditions that affect desulfurization efficiency are investigated. • The reaction process of model sulfur compounds is proposed.

  11. Desulfurization of coal and petroleum. (Latest citations from the NTIS bibliographic database). Published Search

    SciTech Connect

    1996-04-01

    The bibliography contains citations concerning the desulfurization of coal, coal liquids, and crude oil. Flotation heap leaching, oxydesulfurization, metal oxide, microwave process, and chlorination are among the pre-combustion processes discussed. Coal liquefaction and gasification are only included if sulfur removal is stressed. Flue gas desulfurization and other post-combustion sulfur control processes are excluded. (Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)

  12. Key factor in rice husk ash/CaO sorbent for high flue gas desulfurization activity

    SciTech Connect

    Irvan Dahlan; Keat Teong Lee; Azlina Harun Kamaruddin; Abdul Rahman Mohamed

    2006-10-01

    Siliceous materials such as rice husk ash (RHA) have potential to be utilized as high performance sorbents for the flue gas desulfurization process in small-scale industrial boilers. This study presents findings on identifying the key factor for high desulfurization activity in sorbents prepared from RHA. Initially, a systematic approach using central composite rotatable design was used to develop a mathematical model that correlates the sorbent preparation variables to the desulfurization activity of the sorbent. The sorbent preparation variables studied are hydration period, x{sub 1} (6-16 h), amount of RHA, x{sub 2} (5-15 g), amount of CaO, x{sub 3} (2-6 g), amount of water, x{sub 4} (90-110 mL), and hydration temperature, x{sub 5} (150-250{sup o}C). The mathematical model developed was subjected to statistical tests and the model is adequate for predicting the SO{sub 2} desulfurization activity of the sorbent within the range of the sorbent preparation variables studied. Based on the model, the amount of RHA, amount of CaO, and hydration period used in the preparation step significantly influenced the desulfurization activity of the sorbent. The ratio of RHA and CaO used in the preparation mixture was also a significant factor that influenced the desulfurization activity of the sorbent. A RHA to CaO ratio of 2.5 leads to the formation of specific reactive species in the sorbent that are believed to be the key factor responsible for high desulfurization activity in the sorbent. Other physical properties of the sorbent such as pore size distribution and surface morphology were found to have insignificant influence on the desulfurization activity of the sorbent. 31 refs., 5 figs., 3 tabs.

  13. Nektar++: An open-source spectral/ hp element framework

    NASA Astrophysics Data System (ADS)

    Cantwell, C. D.; Moxey, D.; Comerford, A.; Bolis, A.; Rocco, G.; Mengaldo, G.; De Grazia, D.; Yakovlev, S.; Lombard, J.-E.; Ekelschot, D.; Jordi, B.; Xu, H.; Mohamied, Y.; Eskilsson, C.; Nelson, B.; Vos, P.; Biotto, C.; Kirby, R. M.; Sherwin, S. J.

    2015-07-01

    Nektar++ is an open-source software framework designed to support the development of high-performance scalable solvers for partial differential equations using the spectral/ hp element method. High-order methods are gaining prominence in several engineering and biomedical applications due to their improved accuracy over low-order techniques at reduced computational cost for a given number of degrees of freedom. However, their proliferation is often limited by their complexity, which makes these methods challenging to implement and use. Nektar++ is an initiative to overcome this limitation by encapsulating the mathematical complexities of the underlying method within an efficient C++ framework, making the techniques more accessible to the broader scientific and industrial communities. The software supports a variety of discretisation techniques and implementation strategies, supporting methods research as well as application-focused computation, and the multi-layered structure of the framework allows the user to embrace as much or as little of the complexity as they need. The libraries capture the mathematical constructs of spectral/ hp element methods, while the associated collection of pre-written PDE solvers provides out-of-the-box application-level functionality and a template for users who wish to develop solutions for addressing questions in their own scientific domains.

  14. A repair station for HpGe detectors

    NASA Astrophysics Data System (ADS)

    Shearman, Robert; Lister, Christopher; Mitchell, A. J.; Copp, Patrick; Jepeal, Steven; Chowdhury, Partha

    2013-10-01

    Hyper-pure Germanium detectors (HpGe) offer the highest energy resolution for gamma-ray nuclear spectroscopy (about 1.5 keV @ 1 MeV), and are used in all the world's leading detector arrays such as GammaSphere, AGATA and GRETINA. The detector crystals are operated in cryostats at 100 K to reduce thermal noise. To maintain low leakage current and low operating temperatures, cryostat hygiene is very important. Detectors must be regularly maintained by using a high-vacuum, oil-free annealing station. At elevated temperatures above 373 K the process of pumping and baking can also anneal away neutron damage to the detector crystals. This poster will show the design and building of a new HpGe repair station at U. Mass Lowell, and make comparisons of results obtained from this new station to the Gammasphere annealing factory at Argonne. This research is funded by the DOE National Nuclear Safety Administration and the Office of Science.

  15. Agricultural use of a flue gas desulfurization by-product

    SciTech Connect

    Dick, W.; Chen, L.; Nelson, S. Jr.

    1998-12-31

    Few, if any, economical alternatives exist for operators of small coal-fired boilers that require a flue-gas desulfurization system which does not generate wastes. A new duct-injection technology called Fluesorbent has been developed to help fill this gap. Fluesorbent FGD was intentionally designed so that the saturated SO{sub 2}-sorbent materials would be valuable soil amendments for agricultural or turf-grass land. Agricultural and turf grass studies recently commenced using spent Fluesorbent materials from an FGD pilot program at an Ohio power plant. In the first year of testing, alfalfa yields on field plots with the FGD by-products were approximately 250% greater than on plots with no treatment, and about 40% greater than on plots treated with an equivalent amount of agricultural lime. Because the FGD by-products contained trace elements from included fly ash, the chemical composition of the alfalfa was significantly improved. Detailed yield and chemical data are presented.

  16. The durability of stabilized flue gas desulfurization sludge

    SciTech Connect

    Chen, X.; Wolfe, W.E.; Hargraves, M.D.

    1995-12-31

    The effects of freeze-thaw cycling on the strength and durability of samples of compacted, stabilized, wet flue gas desulfurization (FGD) by-products are reported. The results of laboratory tests show a clear relationship between higher water contents and increasing vulnerability to freeze-thaw effects. In the samples tested, water contents at or above 40% were characteristic of all the freeze-thaw specimens exhibiting low strengths. Lime content and curing time were also shown to have a marked influence on the durability of the FGD material. It was shown that samples can maintain good strength under freeze-thaw conditions provided 5% lime was added before compaction and the time from compaction to first freeze was at least 60 days.

  17. Application research of integrated desulfurization and dust removal technology

    SciTech Connect

    Fei, S.; Hongsun, J.

    1999-07-01

    The conclusion about the emission control characteristics of the coal-fired power plants is drawn on the basis of investigation in Northeast of China. A simple, reliable and low cost integrated technology instead of many mature but expensive FGD technologies was developed to achieve overall desulfurization and dust removal qualification simultaneously. With the adoption of limestone injection into furnace and three-phase fluidized packing column transformation, the technology is especially suitable for retrofit of existing units between 50MW and 200MW that are commonly equipped with wet scrubbers. The feasibility of retrofit application to a 220t/h boiler is demonstrated according to technical and economic research and design. The new FGD project is capable of meeting environment demand with minimal modification and capital and operating cost, while ensuring uninterrupted and safe power generation.

  18. Washing tower for the desulfurization of flue gases

    SciTech Connect

    Stehning, W.

    1985-05-07

    A scrubber is provided with a grate in its sump through which oxygen is introduced to separate the oxidation zone above this grate from a reaction zone below the grate, a calcium containing additive being introduced into this reaction zone. Flue gas to be desulfurized is passed through a washing zone above the sump and there contacted with normally circulating scrubbing liquid containing the additive to absorb sulfur dioxide and sulfur trioxide. The sulfur dioxide is oxidized to sulfur trioxide and the additive induces precipitation of calcium sulfate in the sump. After a prolonged standstill, settled solids in the sump are induced into movement by drawing a portion of the sump liquid from an upper part thereof and injecting it into a lower part of the sump.

  19. BENCH-SCALE DEMONSTRATION OF HOT-GAS DESULFURIZATION TECHNOLOGY

    SciTech Connect

    Unknown

    1999-10-01

    The U.S. Department of Energy (DOE), Federal Energy Technology Center (FETC), is sponsoring research in advanced methods for controlling contaminants in hot coal gasifier gas (coal-derived fuel-gas) streams of integrated gasification combined-cycle (IGCC) power systems. The hot gas cleanup work seeks to eliminate the need for expensive heat recovery equipment, reduce efficiency losses due to quenching, and minimize wastewater treatment costs. Hot-gas desulfurization research has focused on regenerable mixed-metal oxide sorbents that can reduce the sulfur in coal-derived fuel-gas to less than 20 ppmv and can be regenerated in a cyclic manner with air for multicycle operation. Zinc titanate (Zn{sub 2} TiO{sub 4} or ZnTiO{sub 3}), formed by a solid-state reaction of zinc oxide (ZnO) and titanium dioxide (TiO{sub 2}), is currently one of the leading sorbents. Overall chemical reactions with Zn{sub 2} TiO{sub 4} during the desulfurization (sulfidation)-regeneration cycle are shown below: Sulfidation: Zn{sub 2} TiO{sub 4} + 2H{sub 2}S {yields} 2ZnS + TiO{sub 2} + 2H{sub 2}O; Regeneration: 2ZnS + TiO{sub 2} + 3O{sub 2} {yields} Zn{sub 2} TiO{sub 4} + 2SO{sub 2} The sulfidation/regeneration cycle can be carried out in a fixed-bed, moving-bed, or fluidized-bed reactor configuration. The fluidized-bed reactor configuration is most attractive because of several potential advantages including faster kinetics and the ability to handle the highly exothermic regeneration to produce a regeneration offgas containing a constant concentration of SO{sub 2}.

  20. Separation of Mercury from Flue Gas Desulfurization Scrubber Produced Gypsum

    SciTech Connect

    Hensman, Carl, E., P.h.D; Baker, Trevor

    2008-06-16

    Frontier Geosciences (Frontier; FGS) proposed for DOE Grant No. DE-FG02-07ER84669 that mercury control could be achieved in a wet scrubber by the addition of an amendment to the wet-FGD scrubber. To demonstrate this, a bench-scale scrubber and synthetic flue-gas supply was designed to simulate the limestone fed, wet-desulfurization units utilized by coal-fired power plants. Frontier maintains that the mercury released from these utilities can be controlled and reduced by modifying the existing equipment at installations where wet flue-gas desulfurization (FGD) systems are employed. A key element of the proposal was FGS-PWN, a liquid-based mercury chelating agent, which can be employed as the amendment for removal of all mercury species which enter the wet-FGD scrubber. However, the equipment design presented in the proposal was inadequate to demonstrate these functions and no significant progress was made to substantiate these claims. As a result, funding for a Phase II continuation of this work will not be pursued. The key to implementing the technology as described in the proposal and report appears to be a high liquid-to-gas ratio (L/G) between the flue-gas and the scrubber liquor, a requirement not currently implemented in existing wet-FGD designs. It may be that this constraint can be reduced through parametric studies, but that was not apparent in this work. Unfortunately, the bench-scale system constructed for this project did not function as intended and the funds and time requested were exhausted before the separation studies could occur.

  1. Enhanced durability and reactivity for zinc ferrite desulfurization sorbent

    SciTech Connect

    Berggren, M.H.; Jha, M.C.

    1989-10-01

    AMAX Research Development Center (AMAX R D) investigated methods for enhancing the reactivity and durability of zinc ferrite desulfurization sorbents. Zinc ferrite sorbents are intended for use in desulfurization of hot coal gas in integrated gasification combined cycle (IGCC) or molten carbonate fuel cell (MCFC) applications. For this program, the reactivity of the sorbent may be defined as its sulfur sorption capacity at the breakthrough point and at saturation in a bench-scale, fixed-bed reactor. Durability may be defined as the ability of the sorbent to maintain important physical characteristics such as size, strength, and specific surface area during 10 cycles of sulfidation and oxidation. Two base case sorbents, a spherical pellet and a cylindrical extrude used in related METC-sponsored projects, were used to provide a basis for the aimed enhancement in durability and reactivity. Sorbent performance was judged on the basis of physical properties, single particle kinetic studies based on thermogravimetric (TGA) techniques, and multicycle bench-scale testing of sorbents. A sorbent grading system was utilized to quantify the characteristics of the new sorbents prepared during the program. Significant enhancements in both reactivity and durability were achieved for the spherical pellet shape over the base case formulation. Overall improvements to reactivity and durability were also made to the cylindrical extrude shape. The primary variables which were investigated during the program included iron oxide type, zinc oxide:iron oxide ratio, inorganic binder concentration, organic binder concentration, and induration conditions. The effects of some variables were small or inconclusive. Based on TGA studies and bench-scale tests, induration conditions were found to be very significant.

  2. A NOVEL APPROACH TO CATALYTIC DESULFURIZATION OF COAL

    SciTech Connect

    John G. Verkade

    1997-08-31

    Remarkably mild conditions have been discovered for quantitative sulfur removal from dibenzothiophene and other organosulfur systems using relatively cheap elemental sodium. The project objectives are: (1) Optimize the coal desulfurization reaction with respect to time, temperature, coal type and the R groups (including R = H), and also on extraction, impregnation and sonication conditions; (2) Optimize the conditions for the HDS reaction (which allows the PR{sub 3} to function as an HDS catalyst for coal) with respect to R group, temperature, pressure, H{sub 2} gas flow rate and inert solvent presence; (3) Determine the product(s) and the pathway of the novel redox reaction that appears to quantitatively remove sulfur from dibenzothiophene (DBT) when R = Bu when FeCl{sub 3} is used as a catalyst; (4) Impregnate sulfur-laden coals with Fe{sup 3+} to ascertain if the PR{sub 3} desulfurization rate increases; (5) Determine the nature of the presently unextractable phosphorus compounds formed in solid coals by PR{sub 3}; (6) Explore the efficacy of PR{sub 3}/Fe{sup 3+} in removing sulfur from petroleum feedstocks, heavy ends (whether solid or liquid), coal tar and discarded tire rubber; (7) Explore the possibility of using water-soluble PR{sub 3} compounds and Fe{sup 3+} to remove sulfur from petroleum feedstocks and heavy ends in order to remove the SPR{sub 3} (and Fe{sup 3+} catalyst) by water extraction (for subsequent HDS of the SPR{sub 3}); and (8) Explore the possibility of using solid-supported PR{sub 3} compounds (plus Fe{sup 3+} catalyst) to remove sulfur from petroleum feedstocks and heavy ends in order to keep the oil and the SPR{sub 3} (formed in the reaction) in easily separable phases.

  3. Simulation studies on a prototype ionisation chamber for measurement of personal dose equivalent, Hp(10).

    PubMed

    Cardoso, J; Carvalho, A F; Oliveira, C

    2007-01-01

    A prototype ionisation chamber for direct measurement of the personal dose equivalent, Hp(10), similar to the one developed by the Physikalisch-Technische Bundesantalt (PTB), was designed and constructed by the Metrological Laboratory of Ionizing Radiation (LMRI) of Nuclear and Technological Institute (ITN). Tests already performed have shown that the behaviour of this chamber is very similar to the PTB chamber, mainly the energy dependence for the X-ray radiation qualities of the ISO 4037-1 narrow series N-30, N-40, N-60, N-80, N-100 and N-120 and also for gamma radiation of 137Cs and 60Co. However, the results obtained also show a dependence on the energy and angles of incident radiation and a low magnitude of the electrical response of the ionisation chamber. In order to optimise the performance of the chamber, the LMRI initiated numerical simulation of this ionisation chamber by Monte Carlo method using the MCNPX code.

  4. Recent advances with quiescent power supply current (I(sub DDQ)) testing at Sandia using the HP82000

    NASA Astrophysics Data System (ADS)

    Righter, A. W.; Leong, D. J.; Cox, L. B.

    Last year at the HP82000 Users Group Meeting, Sandia National Laboratories gave a presentation on I(sub DDQ) testing. This year, some advances are presented on this testing including DUT board fixturing, external DC PMU measurement, and automatic IDD-All circuit calibration. Implementation is examined more than theory, with results presented from Sandia tests. After a brief summary I(sub DDQ) theory and testing concepts, how the break (hold state) vector and data formatting present a test vector generation concern for the HP82000 is described. Fixturing of the DUT board for both types of I(sub DDQ) measurement is then discussed, along with how the continuity test and test vector generation must be taken into account. Results of a test including continuity, IDD-All and I(sub DDQ) Value measurements is shown. Next, measurement of low current using an external PMU is discussed, including noise considerations, implementation and some test results showing nA-range measurements. A method is presented for automatic calibration of the IDD-All analog comparator circuit using RM BASIC on the HP82000, with implementation and measurement results. Finally, future directions for research in this area is explored.

  5. Engineering of Helicobacter pylori Dimeric Oxidoreductase DsbK (HP0231)

    PubMed Central

    Bocian-Ostrzycka, Katarzyna M.; Grzeszczuk, Magdalena J.; Banaś, Anna M.; Jastrząb, Katarzyna; Pisarczyk, Karolina; Kolarzyk, Anna; Łasica, Anna M.; Collet, Jean-François; Jagusztyn-Krynicka, Elżbieta K.

    2016-01-01

    The formation of disulfide bonds that are catalyzed by proteins of the Dsb (disulfide bond) family is crucial for the correct folding of many extracytoplasmic proteins. Thus, this formation plays an essential, pivotal role in the assembly of many virulence factors. The Helicobacter pylori disulfide bond-forming system is uncomplicated compared to the best-characterized Escherichia coli Dsb pathways. It possesses only two extracytoplasmic Dsb proteins named HP0377 and HP0231. As previously shown, HP0377 is a reductase involved in the process of cytochrome c maturation. Additionally, it also possesses disulfide isomerase activity. HP0231 was the first periplasmic dimeric oxidoreductase involved in disulfide generation to be described. Although HP0231 function is critical for oxidative protein folding, its structure resembles that of dimeric EcDsbG, which does not confer this activity. However, the HP0231 catalytic motifs (CXXC and the so-called cis-Pro loop) are identical to that of monomeric EcDsbA. To understand the functioning of HP0231, we decided to study the relations between its sequence, structure and activity through an extensive analysis of various HP0231 point mutants, using in vivo and in vitro strategies. Our work shows the crucial role of the cis-Pro loop, as changing valine to threonine in this motif completely abolishes the protein function in vivo. Functioning of HP0231 is conditioned by the combination of CXXC and the cis-Pro loop, as replacing the HP0231 CXXC motif by the motif from EcDsbG or EcDsbC results in bifunctional protein, at least in E. coli. We also showed that the dimerization domain of HP0231 ensures contact with its substrates. Moreover, the activity of this oxidase is independent on the structure of the catalytic domain. Finally, we showed that HP0231 chaperone activity is independent of its redox function. PMID:27507968

  6. Interaction between HP1{alpha} and replication proteins in mammalian cells

    SciTech Connect

    Auth, Tanja . E-mail: tauth@uni-bonn.de; Kunkel, Elisabeth; Grummt, Friedrich . E-mail: grummt@biozentrum.uni-wuerzburg.de

    2006-10-15

    HP1 is an essential heterochromatin-associated protein known to play an important role in the organization of heterochromatin as well as in the transcriptional regulation of heterochromatic and euchromatic genes both in repression and activation. Using the yeast two-hybrid system and immunoprecipitation, we report here that murine HP1{alpha} interacts with the preRC proteins ORC1, ORC2 and CDC6. Immunofluorescence staining and EGFP/DsRed fusion proteins revealed a colocalization of HP1{alpha} with ORC1, ORC2 and CDC6 in heterochromatin, supporting the notion that ORC and probably CDC6 play an important role in murine HP1{alpha} function. Besides that, we also observed a colocalization of HP1{alpha} with {gamma}-tubulin suggesting a centrosomal localization of HP1{alpha} in murine cells. To gain insight into HP1{alpha} function, we applied the RNAi technique. Depletion of HP1{alpha} leads to a slow down of cell proliferation, an aberrant cell cycle progression as well as to multinucleated cells with insufficiently organized microtubule. These results together indicate that HP1{alpha} exerts functions in mitosis and cytokinesis.

  7. Performance of the h, p and h-p versions

    NASA Technical Reports Server (NTRS)

    Babuska, I.; Gui, W.; Szabo, B.

    1984-01-01

    There are three basic versions of the finite element method, called the h, p and h-p versions. They are characterized by the way in which the finite element meshes and polynomial degree of elements are chosen. They differ in computer implementation (program architecture) and mathematical analysis. The manner in which the meshes and polynomial degree of the elements affect the accuracy of finite element solutions is examined. The approach is to fix certain parameters and increase the number of degrees of freedom so that the finie element solutions converge to the exact solution. Such a systematic increase of the number of degrees of freedom is called extension because it can be interpreted as a systematic extension of finite element spaces.

  8. Absolute properties of the triple star HP Aurigae

    SciTech Connect

    Lacy, Claud H. Sandberg; Burks, Charles L.; Torres, Guillermo; Wolf, Marek E-mail: clburks@email.uark.edu E-mail: wolf@cesnet.cz

    2014-01-01

    New photometric, spectroscopic, and eclipse timing observations of the eclipsing binary star HP Aur allow for very accurate orbital determinations, even in the presence of a third body and transient starspot activity. The eclipsing binary masses are determined to an accuracy of ±0.4% and the radii to ±0.6%. The masses are 0.9543 ± 0.0041 and 0.8094 ± 0.0036 solar masses, and the radii are 1.0278 ± 0.0042 and 0.7758 ± 0.0034 solar radii, respectively. The orbital period in the outer orbit is accurately determined for the first time: 4.332 ± 0.011 yr. A comparison with current theories of stellar evolution shows that the components' absolute properties can be well-matched by the current models at an age of about 7 billion years.

  9. A Unix print filter for controlling an HP Laserjet printer

    SciTech Connect

    Hoffman, F.M.

    1992-09-01

    This report describes a Unix print filter designed to control an Hewlett Packard Laserjet or other printer that uses Hewlett Packard's Printer Control Language (HP-PCL). The filter gives users the ability to control print pitch, orientation, and indentation by using standard flags to the Unix 1pr. command or multiple entries in the /etc/printcap file and allows both ascii and binary (i.e., graphics and down-loadable fonts) files to be printed. Additionally, the filter provides some accounting capability. The supported print pitch and orientation options are described, as are the different configuration options. The code for the filter and sample entries for the /etc/printcap file are included.

  10. A Unix print filter for controlling an HP Laserjet printer

    SciTech Connect

    Hoffman, F.M.

    1992-09-01

    This report describes a Unix print filter designed to control an Hewlett Packard Laserjet or other printer that uses Hewlett Packard`s Printer Control Language (HP-PCL). The filter gives users the ability to control print pitch, orientation, and indentation by using standard flags to the Unix 1pr. command or multiple entries in the /etc/printcap file and allows both ascii and binary (i.e., graphics and down-loadable fonts) files to be printed. Additionally, the filter provides some accounting capability. The supported print pitch and orientation options are described, as are the different configuration options. The code for the filter and sample entries for the /etc/printcap file are included.

  11. A Unix Print Filter for Controlling an HP Laserjet Printer

    SciTech Connect

    Hoffman, F.M.

    1992-01-01

    This report describes a Unix print filter designed to control an Hewlett Packard Laserjet or other printer that uses Hewlett Packard's Printer Control Language (HP-PCL). The filter gives users the ability to control print pitch, orientation, and indentation by using standard flags to the Unix lpr command or multiple entries in the /etc/printcap file and allows both ascii and binary (i.e., graphics and down-loadable fonts) files to be printed. Additionally, the filter provides some accounting capability. The supported print pitch and orientation options are described, as are the different configuration options. The code for the filter is included in Appendix A and sample entries for the /etc/printcap file are included in Appendix B and C.

  12. 17. VIEW SOUTHEAST OF 450 HP TURBINE IN BASEMENT OF ...

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

    17. VIEW SOUTHEAST OF 450 HP TURBINE IN BASEMENT OF GRANITEVILLE MILL. THE MAIN BEARING OF THE TURBINE IS AT LEFT CENTER OF THE PHOTOGRAPH. A LOMBARD REGULATOR CAN BE SEEN AT THE LEFT CENTER REAR. THE LARGE HANDWHEEL AT THE LEFT CENTER IS GEARED TO A SECTIONAL GEAR AT THE CENTER OF THE PHOTOGRAPH AND IS USED TO MANUALLY OPEN THE GATES AND ALLOW WATER INTO THE TURBINE. THE SMALL PULLEY ON THE END OF THE MAIN SHAFT NORMALLY WOULD HAVE A BELT CONNECTING IT TO A PULLEY ON THE LOMBARD REGULATOR. THIS BELT TRANSMITTED TURBINE SPEED (RPM) TO THE LOMBARD WHICH WOULD OPEN OR CLOSE THE GATES TO KEEP TURBINE SPEED CONSTANT UNDER VARYING LOADS. THIS TURBINE WAS INSTALLED IN THE REFIT OF 1912. - Graniteville Mill, Marshall Street, Graniteville, Aiken County, SC

  13. 18. VIEW SOUTHWEST OF 450 HP TURBINE INSTALLATION IN BASEMENT ...

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

    18. VIEW SOUTHWEST OF 450 HP TURBINE INSTALLATION IN BASEMENT OF GRANITEVILLE MILL. MAIN FEATURE OF THE PHOTOGRAPH IS THE PENSTOCK CONDUCTING WATER TO THE TURBINE IN THE BACKGROUND. THE PENSTOCK IS OF RIVETED IRON CONSTRUCTION AND REPLACED A WOOD PENSTOCK IN 1882. THE COVERED OPENING IN THE CENTER OF THE PHOTOGRAPH ORIGINALLY CONNECTED TO A STANDPIPE WHICH EXITED VERTICALLY THROUGH THE MILL. THE STANDPIPE MODERATED WATER PRESSURE AND SERVED AS A SAFETY FEATURE IN THE EVENT THE TURBINE GATES WERE RAPIDLY CLOSED. (IF LOAD IN THE MILL WERE SUDDENLY STOPPED-SAY AT QUITTING TIME-THE GATES WOULD SHUT DOWN FLOW TO THE TURBINE. THE STANDPIPE OFFERED A PLACE FOR THE WATER, RAPIDLY MOVING THROUGH THE PENSTOCK, TO ESCAPE. IN A SHUT-DOWN SITUATION WATER WOULD ... - Graniteville Mill, Marshall Street, Graniteville, Aiken County, SC

  14. [Experimental investigation of nano-TiO2 on combustion and desulfurization Catalysis].

    PubMed

    Wang, Shu-qin; Zhao, Yi; Tan, Qian; Xu, Pei-yao

    2008-02-01

    Experiment research of nanometer TiO2 catalytic combustion to CaO desulfurization was studied. Desulfurization effect was measured by the composition analysis of fly ash after combustion and the content of SO2 in flue gas. The effects of analytical grade CaO desulfurization by nanometer TiO2 addition, Ca/S molar ratio, nanometer TiO2 that was prepared at different conditions and combustion temperature were discussed. Desulfurization effects were compared with different coals and Ca-base agents by nanometer TiO2 addition. The reaction products wereanalyzed by X-ray diffraction analysis (XRD) and scanning electron microscopy (SEM) analysis. The combustion desulfurization mechanisms of CaO by nanometer TiO2 addition were discussed. The experiment results show that nanometer TiO2 has good catalytic effect to CaO combustion desulfurization. When nanometer TiO2 was added together with CaO, the optimal addition dosage of nanometer TiO2 is 8%, Ca/S molar ratio is 2 and the combustion temperature is 850 degrees C. The desulfurization efficiency of analytical and industrial grade CaO catalyzed by nanometer TiO2 can achieve to 87.8% and 60.3%, and it increased 13.4% and 29.6% than that without nanometer TiO2. The pore diameter and surface area of different coal ashes with nano-TiO2 addition increase because of the active centers of nano-TiO2 surface which are helpful to the diffusion of SO2 and reaction of SO2 to SO3 and increase the desulphurization efficiency of CaO.

  15. Advanced sulfur control concepts in hot-gas desulfurization technology. Quarterly report, April--June 1994

    SciTech Connect

    Harrison, D.P.

    1994-07-01

    The primary objective of this research project is the direct production of elemental sulfur during the regeneration of known high temperature desulfurization sorbents. The contract was awarded to LSU on April 12, 1994, and this quarterly report covers accomplishments during the first 2 1/2 months of the project. Effort during the initial 2 1/2 month period has been limited to Tasks 1 and 2, and involves a search of the literature to identify concepts for producing elemental sulfur during regeneration of known metal oxide sorbents and a thermodynamic evaluation of these concepts. While searching and evaluating the literature is a continuing process, concentrated effort on that phase is now complete and a detailed summary is included in this report. Three possible concepts for the direct production of elemental sulfur were identified in the LSU proposal, and the literature search has not uncovered any additional concepts. Thus, the three concepts being investigated involve: (1) regeneration with SO{sub 2}, (2) regeneration with mixtures Of 02 and H{sub 2}O, and (3) regeneration with H{sub 2}O. While concept (3) directly produces H{sub 2}S instead of elemental sulfur, the concept is included because the possibility exists for converting H{sub 2}S to elemental sulfur using the Claus process. Each of the concepts will ultimately be compared to the Direct Sulfur Recovery Process (DSRP) under development by RTI. DSRP involves initial sorbent regeneration to SO{sub 2}, and the inclusion of additional processing steps to reduce the SO{sub 2} to elemental sulfur.

  16. Molecular biological enhancement of coal desulfurization: Cloning and expression of the sulfoxide/sulfone/sulfonate/sulfate genes in Pseudomonads and Thiobacillae. [Rhodococcus erythropolis, Thiobacillus acidophilus, Thiobacillus novellus

    SciTech Connect

    Krawiec, S.

    1992-01-01

    Research continues on desulfurization of coal using microorganisms. Topics reported on this quarter include: desulfurization with N1-36 (presumptively identified as Rhodochrous erythropolis), pulsed-field gel electrophoresis of chromosomal DNA's of Thiobacillus spp., and fresh isolates with the presumptive capacity to desulfurize dibenzothiophenes.

  17. Molecular biological enhancement of coal desulfurization: Cloning and expression of the sulfoxide/sulfone/sulfonate/sulfate genes in Pseudomonads and Thiobacillae. Eleventh quarterly report

    SciTech Connect

    Krawiec, S.

    1992-08-01

    Research continues on desulfurization of coal using microorganisms. Topics reported on this quarter include: desulfurization with N1-36 (presumptively identified as Rhodochrous erythropolis), pulsed-field gel electrophoresis of chromosomal DNA`s of Thiobacillus spp., and fresh isolates with the presumptive capacity to desulfurize dibenzothiophenes.

  18. Drosophila Heterochromatin Protein 1 (HP1)/Origin Recognition Complex (ORC) Protein Is Associated with HP1 and ORC and Functions in Heterochromatin-induced Silencing

    PubMed Central

    Shareef, Mohammed Momin; King, Chadwick; Damaj, Mona; Badagu, RamaKrishna; Huang, Da Wei; Kellum, Rebecca

    2001-01-01

    Heterochromatin protein 1 (HP1) is a conserved component of the highly compact chromatin of higher eukaryotic centromeres and telomeres. Cytogenetic experiments in Drosophila have shown that HP1 localization into this chromatin is perturbed in mutants for the origin recognition complex (ORC) 2 subunit. ORC has a multisubunit DNA-binding activity that binds origins of DNA replication where it is required for origin firing. The DNA-binding activity of ORC is also used in the recruitment of the Sir1 protein to silence nucleation sites flanking silent copies of the mating-type genes in Saccharomyces cerevisiae. A fraction of HP1 in the maternally loaded cytoplasm of the early Drosophila embryo is associated with a multiprotein complex containing Drosophila melanogaster ORC subunits. This complex appears to be poised to function in heterochromatin assembly later in embryonic development. Here we report the identification of a novel component of this complex, the HP1/ORC-associated protein. This protein contains similarity to DNA sequence-specific HMG proteins and is shown to bind specific satellite sequences and the telomere-associated sequence in vitro. The protein is shown to have heterochromatic localization in both diploid interphase and mitotic chromosomes and polytene chromosomes. Moreover, the gene encoding HP1/ORC-associated protein was found to display reciprocal dose-dependent variegation modifier phenotypes, similar to those for mutants in HP1 and the ORC 2 subunit. PMID:11408576

  19. Peptide recognition by heterochromatin protein 1 (HP1) chromoshadow domains revisited: Plasticity in the pseudosymmetric histone binding site of human HP1.

    PubMed

    Liu, Yanli; Qin, Su; Lei, Ming; Tempel, Wolfram; Zhang, Yuzhe; Loppnau, Peter; Li, Yanjun; Min, Jinrong

    2017-04-07

    Heterochromatin protein 1 (HP1), a highly conserved non-histone chromosomal protein in eukaryotes, plays important roles in the regulation of gene transcription. Each of the three human homologs of HP1 includes a chromoshadow domain (CSD). The CSD interacts with various proteins bearing the PXVXL motif but also with a region of histone H3 that bears the similar PXXVXL motif. The latter interaction has not yet been resolved in atomic detail. Here we demonstrate that the CSDs of all three human HP1 homologs have comparable affinities to the PXXVXL motif of histone H3. The HP1 C-terminal extension enhances the affinity, as does the increasing length of the H3 peptide. The crystal structure of the human HP1γ CSD (CSDγ) in complex with an H3 peptide suggests that recognition of H3 by CSDγ to some extent resembles CSD-PXVXL interaction. Nevertheless, the prolyl residue of the PXXVXL motif appears to play a role distinct from that of Pro in the known HP1β CSD-PXVXL complexes. We consequently generalize the historical CSD-PXVXL interaction model and expand the search scope for additional CSD binding partners.

  20. Hand-held calculator assists in directional drilling control

    SciTech Connect

    Marsh, J.L.

    1983-01-01

    Describes a procedure for the use of an HP-41C to correct error terms due to scale factor, bias, temperature, and misalignment errors in the individual magnetic and gravity sensors used in a borehole angle measurement system. Borehole angle sensors as used in a directional measurement system often have errors due to a variety of different sources. Presents figures showing an example coefficient list for a complete sensor; user instructions; a program listing of ''Errors'' for an HP-41C programmable calculator with 2 extra HP-82143A printers; example input and output data; and a bar code listing for those readers with HP optical wands.

  1. The Mt. Ochi melange (South Evvia Island, Greece): a case study for HP metamorphism and syn-convergent exhumation.

    NASA Astrophysics Data System (ADS)

    Moustaka, Eleni; Soukis, Konstantinos; Huet, Benjamin; Lozios, Stylianos; Magganas, Andreas

    2014-05-01

    The Attic-Cycladic complex (central Aegean Sea, Greece) experienced profound extension since at least the Oligo-Miocene boundary during which the previously thickened crust was reworked by a series of detachments forming the NE directed North Cycladic Detachment System (NCDS) and the SSW directed West Cycladic Detachment System (WCDS). South Evvia Island is located at the northwestern part of the Attic Cycladic complex linking the highly thinned and polymetamorphosed central part of the complex with mainland Greece. Furthermore, greenschists-facies retrograde metamorphism has only partially overprinted the HP mineral assemblages. Consequently, it is an ideal area to study tectonic processes associated with subduction, HP metamorphism and subsequent exhumation from eclogitic depths to the surface. Geological mapping in 1:2:000 scale revealed that the tectonostratigraphy of Mt. Ochi includes three distinct units all metamorphosed in HP conditions followed by greenschist facies overprint. These units are from top to bottom a) the Ochi Unit, a thick metavolcanosedimentary sequence with some intensely folded cipoline marble intercalations and isolated occurrences of metabasic rocks b) the ophiolitic mélange (metagabbros, metawherlites, peridotites, metabasites within a metasedimentary+serpentinite matrix) and c) the lowermost Styra Unit, a cipoline marble-dominated unit with thin mica schists and rare quartzitic layers often boudinaged. The thrust fault that was responsible for the juxtaposition of these three units acted in an early stage during HP metamorphism and it was isoclinally folded and sheared by the following syn-metamorphic deformation events. Detailed structural study in meso- and microscopic scale combined with petrological and geochemical analyses of the Mt Ochi rocks led to the distinction of at least three syn-metamorphic and two post-metamorphic deformation episodes that affected all units. The oldest structure identified is a relic foliation formed

  2. The CompHP Core Competencies Framework for Health Promotion in Europe

    ERIC Educational Resources Information Center

    Barry, Margaret M.; Battel-Kirk, Barbara; Dempsey, Colette

    2012-01-01

    Background: The CompHP Project on Developing Competencies and Professional Standards for Health Promotion in Europe was developed in response to the need for new and changing health promotion competencies to address health challenges. This article presents the process of developing the CompHP Core Competencies Framework for Health Promotion across…

  3. POF and HP1 bind expressed exons, suggesting a balancing mechanism for gene regulation.

    PubMed

    Johansson, Anna-Mia; Stenberg, Per; Pettersson, Fredrik; Larsson, Jan

    2007-11-01

    Two specific chromosome-targeting and gene regulatory systems are present in Drosophila melanogaster. The male X chromosome is targeted by the male-specific lethal complex believed to mediate the 2-fold up-regulation of the X-linked genes, and the highly heterochromatic fourth chromosome is specifically targeted by the Painting of Fourth (POF) protein, which, together with heterochromatin protein 1 (HP1), modulates the expression level of genes on the fourth chromosome. Here we use chromatin immunoprecipitation and tiling microarray analysis to map POF and HP1 on the fourth chromosome in S2 cells and salivary glands at high resolution. The enrichment profiles were complemented by transcript profiles to examine the link between binding and transcripts. The results show that POF specifically binds to genes, with a strong preference for exons, and the HP1 binding profile is a mirror image of POF, although HP1 displays an additional "peak" in the promoter regions of bound genes. HP1 binding within genes is much higher than the basal HP1 enrichment on Chromosome 4. Our results suggest a balancing mechanism for the regulation of the fourth chromosome where POF and HP1 competitively bind at increasing levels with increased transcriptional activity. In addition, our results contradict transposable elements as a major nucleation site for HP1 on the fourth chromosome.

  4. Draft Genome Sequence of Photorhabdus luminescens subsp. laumondii HP88, an Entomopathogenic Bacterium Isolated from Nematodes

    PubMed Central

    Ghazal, Shimaa; Oshone, Rediet; Simpson, Stephen; Morris, Krystalynne; Abebe-Akele, Feseha; Thomas, W. Kelley; Khalil, Kamal M.

    2016-01-01

    Photorhabdus luminescens subsp. laumondii HP88 is an entomopathogenic bacterium that forms a symbiotic association with Heterorhabditis nematodes. We report here a 5.27-Mbp draft genome sequence for P. luminescens subsp. laumondii HP88, with a G+C content of 42.4% and containing 4,243 candidate protein-coding genes. PMID:26988056

  5. Simultaneous desulfurization and denitrification by microwave reactor with ammonium bicarbonate and zeolite.

    PubMed

    Wei, Zaishan; Lin, Zhehang; Niu, Hejingying; He, Haiming; Ji, Yongfeng

    2009-03-15

    Microwave reactor with ammonium bicarbonate (NH(4)HCO(3)) and zeolite was set up to study the simultaneous removal of sulfur dioxide (SO(2)) and nitrogen oxides (NO(x)) from flue gas. The results showed that the microwave reactor filled with NH(4)HCO(3) and zeolite could reduce SO(2) to sulfur with the best desulfurization efficiency of 99.1% and reduce NO(x) to nitrogen with the best NO(x) purifying efficiency of 86.5%. Microwave desulfurization and denitrification effect of the experiment using ammonium bicarbonate and zeolite together is much higher than that using ammonium bicarbonate or zeolite only. NO(x) concentration has little effect on denitrification but has no influence on desulfurization, SO(2) concentration has no effect on denitrification. The optimal microwave power and empty bed residence time (EBRT) on simultaneous desulfurization and dentrification are 211-280 W and 0.315 s, respectively. The mechanism for microwave reduced desulfurization and denitrification can be described as the microwave-induced catalytic reduction reaction between SO(2), NO(x) and ammonium bicarbonate with zeolite being the catalyst and microwave absorbent.

  6. Roles of Electrolyte Characterization on Bauxite Electrolysis Desulfurization with Regeneration and Recycling

    NASA Astrophysics Data System (ADS)

    Gong, Xuzhong; Wang, Zhi; Zhuang, Siyuan; Wang, Dong; Wang, Yuhua; Wang, Mingyong

    2017-02-01

    The recycling of NaCl used as supporting electrolyte for bauxite electrolysis was carried out in this study. The electrolyte was regenerated by adding anhydrous CaCl2 into the solution after filtration, and effects of electrolyte characterization on bauxite electrolysis were examined by observing the change in desulfurization ratio and cell voltage. The results indicated that the desulfurization ratio increased with increasing recycling times of electrolyte. In the meantime, the increase in recycling times has led to the decrease in pH value as well as the increase in Fe ion concentration in the electrolyte, which were the main reasons for the increase in the desulfurization ratio with increasing recycling of electrolyte. The pH value of electrolyte after second electrolysis was lower than 1.5, and the desulfurization ratio increased obviously due to the increase in Fe3+ concentration and suppression of jarosite formation. The increase in Ca2+ concentration did not apparently change desulfurization ratio and anode surface activity. However, with Ca2+ addition, the cathode surface was covered by CaSO4·nH2O, thus resulting in the increase of cell voltage.

  7. Molecular modeling and cytotoxicity of diffractaic acid: HP-β-CD inclusion complex encapsulated in microspheres.

    PubMed

    Silva, Camilla V N S; Barbosa, Jéssica A P; Ferraz, Milena S; Silva, Nicácio H; Honda, Neli K; Rabello, Marcelo M; Hernandes, Marcelo Z; Bezerra, Beatriz P; Cavalcanti, Isabella M F; Ayala, Alejandro P; Santos, Noemia P S; Santos-Magalhães, Nereide S

    2016-11-01

    In this pioneer study, 2-hydroxypropyl-β-cyclodextrin (HP-β-CD) was used to improve the solubility of the diffractaic acid (DA) via inclusion complex (DA:HP-β-CD). Subsequently, DA:HP-β-CD was incorporated into poly-ε-caprolactone (PCL) microspheres (DA:HP-β-CD-MS). Microspheres containing DA (DA-MS) or DA:HP-β-CD (DA:HP-β-CD-MS) were prepared using the multiple W/O/W emulsion-solvent evaporation technique. The phase-solubility diagram of DA in HP-β-CD (10-50mM) showed an AL type curve with a stability constant K1:1=821M(-1). (1)H NMR, FTIR, X-ray diffraction and thermal analysis showed changes in the molecular environment of DA in DA:HP-β-CD. The molecular modeling approach suggests a guest-host complex formation between the carboxylic moiety of both DA and the host (HP-β-CD). The mean particle size of the microspheres were ∅DA-MS=5.23±1.65μm and ∅DA:HP-β-CD-MS=4.11±1.39μm, respectively. The zeta potential values of the microspheres were ζDA-MS=-7.85±0.32mV and ζDA:HP-β-CD-MS=-6.93±0.46mV. Moreover, the encapsulation of DA:HP-β-CD into microspheres resulted in a more slower release (k2=0.042±0.001; r(2)=0.996) when compared with DA-MS (k2=0.183±0.005; r(2)=0.996). The encapsulation of DA or DA:HP-β-CD into microspheres reduced the cytotoxicity of DA (IC50=43.29μM) against Vero cells (IC50 of DA-MS=108.48μM and IC50 of DA:HP-β-CD-MS=142.63μM).

  8. Development of a new ionisation chamber, for HP(10) measurement, using Monte-Carlo simulation and experimental methods.

    PubMed

    Silva, H; Cardoso, J; Oliveira, C

    2011-03-01

    An ionisation chamber that directly measures the quantity personal dose equivalent, H(p)(10), is used as a secondary standard in some metrology laboratories. An ionisation chamber of this type was first developed by Ankerhold. Using the Monte-Carlo simulation, the dose in the sensitive volume as a function of the IC dimensions and the effects of the several components of the ionising chamber have been investigated. Based on these results, a new ionising chamber, lighter than the previous ones, is constructed and experimentally tested.

  9. TSOL18/HP6-Tsol, an immunogenic Taenia solium oncospheral adhesion protein and potential protective antigen.

    PubMed

    Parkhouse, R Michael E; Bonay, Pedro; González, Luis Miguel; Ferrer, Elizabeth; Gárate, Teresa; Aguilar, Cruz M; Cortez A, Milagros M; Harrison, Leslie J S

    2008-04-01

    In this study, we employed Taenia solium mRNA extracted from a tapeworm of Venezuelan origin to clone express and test the recombinant protein of the T. solium homologue of the 18-kDa oncospheral adhesion molecule of Taenia saginata (HP6-Tsag/TSA18). We first confirm the conserved nature of the sequence of the T. solium homologue (TSOL18/HP6-Tsol) and demonstrate that the recombinant protein, which, as with its T. saginata homologue, is characterised by a fibronectin type III homology region, functions as an adhesion molecule. This emphasises the possible importance of TSOL18/HP6-Tsol in tissue invasion, thus providing a rational explanation for its efficacy as a vaccine. As protection against Taenia spp., oncospheres is antibody mediated, logically, therefore, TSOL18/HP6-Tsol may also serve as a diagnostic antigen, as is indeed the case for recombinant HP6-Tsag/TSA18.

  10. Recurring exon deletions in the haptoglobin (HP) gene associate with lower blood cholesterol levels

    PubMed Central

    Boettger, Linda M.; Salem, Rany M.; Handsaker, Robert E.; Peloso, Gina; Kathiresan, Sekar; Hirschhorn, Joel; McCarroll, Steven A.

    2016-01-01

    Two exons of the human haptoglobin (HP) gene exhibit copy number variation that affects HP multimerization and underlies one of the first protein polymorphisms identified in humans. The evolutionary origins and medical significance of this polymorphism have been uncertain. Here we show that this variation has likely arisen from the recurring reversion of an ancient hominin-specific duplication of these exons. Though this polymorphism has been largely invisible to genome-wide genetic studies to date, we describe a way to analyze it by imputation from SNP haplotypes and find among 22,288 individuals that these HP exonic deletions associate with reduced LDL and total cholesterol levels. We show that these deletions, and a SNP that affects HP expression, are the likely drivers of the strong but complex association of cholesterol levels to SNPs near HP. Recurring exonic deletions in the haptoglobin gene likely enhance human health by lowering cholesterol levels in the blood. PMID:26901066

  11. Emergent protein folding modeled with evolved neural cellular automata using the 3D HP model.

    PubMed

    Santos, José; Villot, Pablo; Diéguez, Martin

    2014-11-01

    We used cellular automata (CA) for the modeling of the temporal folding of proteins. Unlike the focus of the vast research already done on the direct prediction of the final folded conformations, we will model the temporal and dynamic folding process. To reduce the complexity of the interactions and the nature of the amino acid elements, lattice models like HP were used, a model that categorizes the amino acids regarding their hydrophobicity. Taking into account the restrictions of the lattice model, the CA model defines how the amino acids interact through time to obtain a folded conformation. We extended the classical CA models using artificial neural networks for their implementation (neural CA), and we used evolutionary computing to automatically obtain the models by means of Differential Evolution. As the iterative folding also provides the final folded conformation, we can compare the results with those from direct prediction methods of the final protein conformation. Finally, as the neural CA that provides the iterative folding process can be evolved using several protein sequences and used as operators in the folding of another protein with different length, this represents an advantage over the NP-hard complexity of the original problem of the direct prediction.

  12. Gas suspension absorption demonstrated for flue gas desulfurization

    SciTech Connect

    1994-03-01

    The first U.S. demonstration of gas suspension absorption (GSA), a flue gas desulfurization (FGD) technology developed in Europe, has been conducted at the Tennessee Valley Authority`s National Center for Emissions Research (NCER) in Paducah, Kentucky. The technology was developed by the Danish company FLS miljo a/s. GSA is an attractive FGD candidate technology because, unlike conventional wet scrubbing, GSA requires no chemical analyses as part of its routine operation and maintenance. The 10-MW GSA demonstration plant was constructed by AirPol, Inc. (Teterboro, New Jersey), a U.S. subsidiary of FLS miljo a/s. The project was partially funded by the U.S. Department of Energy (DOE) through its clean coal technology program. GSA technology and results of the demonstration project are discussed in this paper in brief. The factorial tests conducted on the GSA demonstration plant at NCER showed that, using a modest Ca/S ratio, the system can achieve high SO{sub 2} removal efficiencies, low particulate emissions, and a low-moisture solid waste by-product. 1 ref., 3 figs., 1 tab.

  13. Characteristics of pneumatically-emplaced dry flue gas desulfurization materials

    SciTech Connect

    Carter, S.D.; Rathbone, R.F.; Graham, U.M.; Robl, T.L.

    1996-12-31

    The University of Kentucky in collaboration with the Department of Energy, Addington, Inc. and Costain Coal is currently developing a commercial concept for the haul back of dry flue gas desulfurization materials (FGDM) into highwall mine adits. The University`s Center for Applied Energy Research (CAER) is investigating emplacement systems for a mine demonstration which is planned for the third quarter of 1996. A laboratory-scale transport system has been built at the CAER to evaluate the potential of pneumatic transport for FGDM emplacement. The system is modeled after shotcreting systems in which water is mixed with cement (FGDM) in a nozzle at the end of the pneumatic pipe. Solids travel approximately 70 ft in the lab-scale system at a rate of up to 6 lb FGDM/minute prior to impingement onto a sample collector. Prehydrated FGDM from a circulating fluidized bed combustor has been successfully emplaced onto vertically positioned sample surfaces without excessive dust liberation. The test program is focussed on determining the pneumatic conditions necessary to maximize the strength of the emplaced FGDM under anticipated mine curing conditions while minimizing dust formation. The mineralogy and strength of a pneumatically created sample are described following curing for 60 days.

  14. Coal desulfurization by a microwave process. Technical progress report

    SciTech Connect

    Zavitsanos, P.D.; Golden, J.A.; Bleiler, K.W.

    1982-01-01

    Desulfurization experiments have been carried out using the moving bed flow reactor to examine the following: (1) hardgrove grindability index of microwave treated coal compared with raw coal; (2) washability of microwave treated coal compared with raw coal; (3) the extent of sulfur and ash removal from alkali/coal treated samples. In the washability experiments, the following treatment sequence was carried out: expose raw coal (1-2'' size) to microwaves (2 kW power level, 120 to 240 sec exposure); crush (30 to 200 mesh); float/sink (1.6 S.G.). Sulfur, ash and CV measurements were made on the float fractions for comparison with similar measurements on raw coal float samples prepared in the same way as microwave treated samples. Table 2 is a summary of the sulfur, ash and calorific value analyses comparing washed with raw coal samples. These data were used to calculate percent energy recovery as shown in the table. It is not possible to conclude from the data taken to date whether there is beneficiation from microwave treated-washed coal since two coals showed increased energy recovery and two did not. Additional washability data will be taken to pursue this question.

  15. Microbial communities associated with wet flue gas desulfurization systems

    PubMed Central

    Brown, Bryan P.; Brown, Shannon R.; Senko, John M.

    2012-01-01

    Flue gas desulfurization (FGD) systems are employed to remove SOx gasses that are produced by the combustion of coal for electric power generation, and consequently limit acid rain associated with these activities. Wet FGDs represent a physicochemically extreme environment due to the high operating temperatures and total dissolved solids (TDS) of fluids in the interior of the FGD units. Despite the potential importance of microbial activities in the performance and operation of FGD systems, the microbial communities associated with them have not been evaluated. Microbial communities associated with distinct process points of FGD systems at several coal-fired electricity generation facilities were evaluated using culture-dependent and -independent approaches. Due to the high solute concentrations and temperatures in the FGD absorber units, culturable halothermophilic/tolerant bacteria were more abundant in samples collected from within the absorber units than in samples collected from the makeup waters that are used to replenish fluids inside the absorber units. Evaluation of bacterial 16S rRNA genes recovered from scale deposits on the walls of absorber units revealed that the microbial communities associated with these deposits are primarily composed of thermophilic bacterial lineages. These findings suggest that unique microbial communities develop in FGD systems in response to physicochemical characteristics of the different process points within the systems. The activities of the thermophilic microbial communities that develop within scale deposits could play a role in the corrosion of steel structures in FGD systems. PMID:23226147

  16. Enhanced durability of desulfurization sorbents for fluidized-bed applications

    SciTech Connect

    Gupta, R.P.; Gangwal, S.K.

    1991-06-01

    Advanced integrated gasification combined cycle (IGCC) power systems require the development of high-temperature desulfurization sorbents capable of removing hydrogen sulfide from coal gasifier down to very low levels. The objective of this investigation was to identify and demonstrate methods for enhancing the long-term chemical reactivity and mechanical strength of zinc ferrite, a leading regenerable sorbent, for fluidized-bed applications. Fluidized sorbent beds offer significant potential in IGCC systems because of their ability to control the highly exothermic regeneration involved. However, fluidized beds require a durable, attrition-resistant sorbent in the 100--300 {mu}m size range. A bench-scale high-temperature, high- pressure (HTHP) fluidized-bed reactor (7.6-cm I.D.) system capable of operating up to 24 atm and 800{degree}C was designed, built and tested. A total of 175 sulfidation-regeneration cycles were carried out using KRW-type coal gas with various zinc ferrite formulations. A number of sorbent manufacturing techniques including spray drying, impregnation, crushing and screening, and granulation were investigated. While fluidizable sorbents prepared by crushing durable pellets and screening had acceptable sulfur capacity, they underwent excessive attrition during multicycle testing. The sorbent formulations prepared by a proprietary technique were found to have excellent attrition resistance and acceptable chemical reactivity during multicycle testing. However, zinc ferrite was found to be limited to 550{degree}C, beyond which excessive sorbent weakening due to chemical transformations, e.g., iron oxide reduction, was observed.

  17. Producing ammonium sulfate from flue gas desulfurization by-products

    USGS Publications Warehouse

    Chou, I.-Ming; Bruinius, J.A.; Benig, V.; Chou, S.-F.J.; Carty, R.H.

    2005-01-01

    Emission control technologies using flue gas desulfurization (FGD) have been widely adopted by utilities burning high-sulfur fuels. However, these technologies require additional equipment, greater operating expenses, and increased costs for landfill disposal of the solid by-products produced. The financial burdens would be reduced if successful high-volume commercial applications of the FGD solid by-products were developed. In this study, the technical feasibility of producing ammonium sulfate from FGD residues by allowing it to react with ammonium carbonate in an aqueous solution was preliminarily assessed. Reaction temperatures of 60, 70, and 80??C and residence times of 4 and 6 hours were tested to determine the optimal conversion condition and final product evaluations. High yields (up to 83%) of ammonium sulfate with up to 99% purity were achieved under relatively mild conditions. The optimal conversion condition was observed at 60??C and a 4-hour residence time. The results of this study indicate the technical feasibility of producing ammonium sulfate fertilizer from an FGD by-product. Copyright ?? Taylor & Francis Inc.

  18. Ductwork: Materials of construction for flue gas desulfurization systems

    SciTech Connect

    O`Donnell, R.J.; Khederian, J.C.; Martin, J.E.; Watson, W.K.

    1995-09-01

    This paper identifies the ductwork materials required for the various service conditions in the wet limestone flue gas desulfurization system (FGDS) at Indianapolis Power and Light Company`s (IPL) Petersburg Units 1 and 2. This project was initiated by IPL in response to the Clean Air Act Amendments (CAAA) of 1990 and is intended to treat the flue gas from two base-loaded units with a combined capacity of approximately 700 MW gross electrical output. The flue gas conditions include hot unscrubbed gas (bypass), hot unscrubbed gas mixed with cool ambient air (normal), a mixing zone of gas only/air only associated with an open bypass system (no damper), and cool, wet scrubbed gas (outlet ducts). In addition, there are upset conditions associated with the loss of an air preheater. This system is somewhat unique, in that each unit has its own separate open or undampered bypass system, including separate stack liners. While a separate bypass system eliminates the extremely severe corrosion problems associated with mixing unscrubbed gas and scrubbed gas in a common bypass flue, it does create potential problems mixing cool ambient air with hot flue gas.

  19. Microbial communities associated with wet flue gas desulfurization systems.

    PubMed

    Brown, Bryan P; Brown, Shannon R; Senko, John M

    2012-01-01

    Flue gas desulfurization (FGD) systems are employed to remove SO(x) gasses that are produced by the combustion of coal for electric power generation, and consequently limit acid rain associated with these activities. Wet FGDs represent a physicochemically extreme environment due to the high operating temperatures and total dissolved solids (TDS) of fluids in the interior of the FGD units. Despite the potential importance of microbial activities in the performance and operation of FGD systems, the microbial communities associated with them have not been evaluated. Microbial communities associated with distinct process points of FGD systems at several coal-fired electricity generation facilities were evaluated using culture-dependent and -independent approaches. Due to the high solute concentrations and temperatures in the FGD absorber units, culturable halothermophilic/tolerant bacteria were more abundant in samples collected from within the absorber units than in samples collected from the makeup waters that are used to replenish fluids inside the absorber units. Evaluation of bacterial 16S rRNA genes recovered from scale deposits on the walls of absorber units revealed that the microbial communities associated with these deposits are primarily composed of thermophilic bacterial lineages. These findings suggest that unique microbial communities develop in FGD systems in response to physicochemical characteristics of the different process points within the systems. The activities of the thermophilic microbial communities that develop within scale deposits could play a role in the corrosion of steel structures in FGD systems.

  20. SCALE-UP OF ADVANCED HOT-GAS DESULFURIZATION SORBENTS

    SciTech Connect

    K. JOTHIMURUGESAN; S.K. GANGWAL

    1998-03-01

    The objective of this study was to develop advanced regenerable sorbents for hot gas desulfurization in IGCC systems. The specific objective was to develop durable advanced sorbents that demonstrate a strong resistance to attrition and chemical deactivation, and high sulfidation activity at temperatures as low as 343 C (650 F). Twenty sorbents were synthesized in this work. Details of the preparation technique and the formulations are proprietary, pending a patent application, thus no details regarding the technique are divulged in this report. Sulfidations were conducted with a simulated gas containing (vol %) 10 H{sub 2}, 15 CO, 5 CO{sub 2}, 0.4-1 H{sub 2}S, 15 H{sub 2}O, and balance N{sub 2} in the temperature range of 343-538 C. Regenerations were conducted at temperatures in the range of 400-600 C with air-N{sub 2} mixtures. To prevent sulfation, catalyst additives were investigated that promote regeneration at lower temperatures. Characterization were performed for fresh, sulfided and regenerated sorbents.

  1. Economic assessment of advanced flue gas desulfurization processes. Final report

    SciTech Connect

    Bierman, G. R.; May, E. H.; Mirabelli, R. E.; Pow, C. N.; Scardino, C.; Wan, E. I.

    1981-09-01

    This report presents the results of a project sponsored by the Morgantown Energy Technology Center (METC). The purpose of the study was to perform an economic and market assessment of advanced flue gas desulfurization (FGD) processes for application to coal-fired electric utility plants. The time period considered in the study is 1981 through 1990, and costs are reported in 1980 dollars. The task was divided into the following four subtasks: (1) determine the factors affecting FGD cost evaluations; (2) select FGD processes to be cost-analyzed; (3) define the future electric utility FGD system market; and (4) perform cost analyses for the selected FGD processes. The study was initiated in September 1979, and separate reports were prepared for the first two subtasks. The results of the latter two subtasks appear only in this final reprot, since the end-date of those subtasks coincided with the end-date of the overall task. The Subtask 1 report, Criteria and Methods for Performing FGD Cost Evaluations, was completed in October 1980. A slightly modified and condensed version of that report appears as appendix B to this report. The Subtask 2 report, FGD Candidate Process Selection, was completed in January 1981, and the principal outputs of that subtask appear in Appendices C and D to this report.

  2. Apparatus and method for the desulfurization of petroleum by bacteria

    DOEpatents

    Lizama, Hector M.; Scott, Timothy C.; Scott, Charles D.

    1995-01-01

    A method for treating petroleum with anaerobic microorganisms acting as biocatalysts that can remove sulfur atoms from hydrocarbon molecules, under anaerobic conditions, and then convert the sulfur atoms to hydrogen sulfide. The microorganisms utilized are from the family known as the "Sulfate Reducing Bacteria." These bacteria generate metabolic energy from the oxidation of organic compounds, but use oxidized forms of sulfur as an electron acceptor. Because the biocatalyst is present in the form of bacteria in an aqueous suspension, whereas the reacting substrate consists of hydrocarbon molecules in an organic phase, the actual desulfurization reaction takes place at the aqueous-organic interphase. To ensure adequate interfacial contacting and mass transfer, a biphasic electrostatic bioreactor system is utilized. The bioreactor is utilized to disperse and recoalesce a biocatalyst contained in the aqueous liquid phase into the organic liquid phase containing the sulfur. High-intensity electrical fields rupture the aqueous drops into a plurality of microdroplets and induce continuous coalescence and redispersion as the microdroplets travel through the organic phase, thus increasing surface area. As the aqueous microdroplets progress through the organic phase, the biocatalyst then reacts with the sulfur to produce hydrogen sulfide which is then removed from the bioreactor. The organic liquid, now free of the sulfur, is ready for immediate use or further processing.

  3. Apparatus and method for the desulfurization of petroleum by bacteria

    DOEpatents

    Lizama, H.M.; Scott, T.C.; Scott, C.D.

    1995-10-17

    A method is described for treating petroleum with anaerobic microorganisms acting as biocatalysts that can remove sulfur atoms from hydrocarbon molecules, under anaerobic conditions, and then convert the sulfur atoms to hydrogen sulfide. The microorganisms utilized are from the family known as the ``Sulfate Reducing Bacteria``. These bacteria generate metabolic energy from the oxidation of organic compounds, but use oxidized forms of sulfur as an electron acceptor. Because the biocatalyst is present in the form of bacteria in an aqueous suspension, whereas the reacting substrate consists of hydrocarbon molecules in an organic phase, the actual desulfurization reaction takes place at the aqueous-organic interphase. To ensure adequate interfacial contacting and mass transfer, a biphasic electrostatic bioreactor system is utilized. The bioreactor is utilized to disperse and recoalesce a biocatalyst contained in the aqueous liquid phase into the organic liquid phase containing the sulfur. High-intensity electrical fields rupture the aqueous drops into a plurality of microdroplets and induce continuous coalescence and redispersion as the microdroplets travel through the organic phase, thus increasing surface area. As the aqueous microdroplets progress through the organic phase, the biocatalyst then reacts with the sulfur to produce hydrogen sulfide which is then removed from the bioreactor. The organic liquid, now free of the sulfur, is ready for immediate use or further processing. 5 figs.

  4. HP1a Targets the Drosophila KDM4A Demethylase to a Subset of Heterochromatic Genes to Regulate H3K36me3 Levels

    PubMed Central

    Lin, Chia-Hui; Paulson, Ariel; Abmayr, Susan M.; Workman, Jerry L.

    2012-01-01

    The KDM4 subfamily of JmjC domain-containing demethylases mediates demethylation of histone H3K36me3/me2 and H3K9me3/me2. Several studies have shown that human and yeast KDM4 proteins bind to specific gene promoters and regulate gene expression. However, the genome-wide distribution of KDM4 proteins and the mechanism of genomic-targeting remain elusive. We have previously identified Drosophila KDM4A (dKDM4A) as a histone H3K36me3 demethylase that directly interacts with HP1a. Here, we performed H3K36me3 ChIP-chip analysis in wild type and dkdm4a mutant embryos to identify genes regulated by dKDM4A demethylase activity in vivo. A subset of heterochromatic genes that show increased H3K36me3 levels in dkdm4a mutant embryos overlap with HP1a target genes. More importantly, binding to HP1a is required for dKDM4A-mediated H3K36me3 demethylation at a subset of heterochromatic genes. Collectively, these results show that HP1a functions to target the H3K36 demethylase dKDM4A to heterochromatic genes in Drosophila. PMID:22761891

  5. Ultrasound-assisted oxidative desulfurization of bunker-C oil using tert-butyl hydroperoxide.

    PubMed

    Tang, Qiong; Lin, Song; Cheng, Ying; Liu, Sujun; Xiong, Jun-Ru

    2013-09-01

    This work investigated the ultrasonic assisted oxidative desulfurization of bunker-C oil with TBHP/MoO3 system. The operational parameters for the desulfurization procedure such as ultrasonic irradiation time, ultrasonic wave amplitude, catalyst initial concentration and oxidation agent initial concentration were studied. The experimental results show that the present oxidation system was very efficient for the desulfurization of bunker-C oil and ~35% sulfur was removed which was dependent on operational parameters. The application of ultrasonic irradiation allowed sulfur removal in a shorter time. The stronger the solvent polarity is, the higher the sulfur removal rate, but the recovery rate of oil is lower. The sulfur compounds in bunker-C oil reacted with TBHP to produce corresponding sulfoxide, and further oxidation produced the corresponding sulfone.

  6. Sulfur-selective desulfurization of dibenzothiophene and diesel oil by newly isolated Rhodococcus sp. strains.

    PubMed

    Castorena, Gladys; Suárez, Claudia; Valdez, Idania; Amador, Guadalupe; Fernández, Luis; Le Borgne, Sylvie

    2002-09-24

    New desulfurizing bacteria able to convert dibenzothiophene into 2-hydroxybiphenyl and sulfate were isolated from contaminated soils collected in Mexican refineries. Random amplified polymorphic DNA analysis showed they were different from previously reported Rhodococcus erythropolis desulfurizing strains. According to 16S rRNA gene sequencing and fatty acid analyses, these new isolates belonged to the genus Rhodococcus. These strains could desulfurize 4,6-dimethyldibenzothiophene which is one of the most difficult dibenzothiophene derivatives to remove by hydrodesulfurization. A deeply hydrodesulfurized diesel oil containing significant amounts of 4,6-dimethyldibenzothiophene was treated with Rhodococcus sp. IMP-S02 cells. Up to 60% of the total sulfur was removed and all the 4,6-dimethyldibenzothiophene disappeared as a result of this treatment.

  7. Identification and cloning of genes involved in specific desulfurization dibenzothiophene by Rhodococcus sp. strain IGTS8

    SciTech Connect

    Denome, S.A.; Young, K.D.; Olson, E.S. )

    1993-09-01

    The presence of sulfur in coal and petroleum contributes to corrosion of production and refining equipment and burning these high-sulfur products emits sulfur oxides to the atmosphere. Microorganisms that can enzymatically release organically bound sulfur from organic components of coal or petroleum or from dibenzothiophene (DBT) could reduce the sulfur content of high sulfur fuels without depleting their British thermal unit value. Two major pathways for microbial metabolism of DBT have been proposed. Some of the genes for the DPT degradative pathway have been isolated and characterized. However, no genes for the desulfurization pathway have been identified. This paper reports the isolation from Rhodoccus sp. strain IGTS8 pf a set of genes that confer a specific desulfurization phenotype to mutants and to a related organism, R. fascians D188-5, that is normally unable to desulfurize DBT. 38 refs., 2 figs., 1 tab.

  8. Molecular biology of coal bio-desulfurization. Quarterly technical progress report, January 1--March 31, 1992

    SciTech Connect

    Young, K.D.; Gallagher, J.R.

    1992-04-30

    Genes cloned from Rhodococcus rhodochrous IGTS8 can transfer the DBT desulfurization phenotype to a different species (R. Fascians). The product was identified as 2-phenylphenol by gas chromatography. This result parallels the results we have previously reported for the activity of these genes in a DBT-negative mutant of IGTS8. Thus, the evidence is strong that we have identified and cloned the entire set of genes that are responsible for this very specific desulfurization reaction. Sequencing of these genes has commenced. A genomic library was constructed from the bacterium, Besulfovibrio desulfuricans. Screening has not yet identified a clone that carries the desulfurization genes from that organism. Two open reading frames, doxH and doxJ, in the C18 DBT degradation pathway were mutated and are now believed to be dispensable to that pathway. Finally, progress was made toward beginning to sequence the DBT dixoygenase genes from strain A15.

  9. Molecular biology of coal bio-desulfurization. [Rhodococcus rhodochrous, Desulfovibrio desulfuricans

    SciTech Connect

    Young, K.D.; Gallagher, J.R.

    1992-04-30

    Genes cloned from Rhodococcus rhodochrous IGTS8 can transfer the DBT desulfurization phenotype to a different species (R. Fascians). The product was identified as 2-phenylphenol by gas chromatography. This result parallels the results we have previously reported for the activity of these genes in a DBT-negative mutant of IGTS8. Thus, the evidence is strong that we have identified and cloned the entire set of genes that are responsible for this very specific desulfurization reaction. Sequencing of these genes has commenced. A genomic library was constructed from the bacterium, Besulfovibrio desulfuricans. Screening has not yet identified a clone that carries the desulfurization genes from that organism. Two open reading frames, doxH and doxJ, in the C18 DBT degradation pathway were mutated and are now believed to be dispensable to that pathway. Finally, progress was made toward beginning to sequence the DBT dixoygenase genes from strain A15.

  10. Evaluation of sulfur-reducing microorganisms for organic desulfurization. [Pyrococcus furiosus

    SciTech Connect

    Miller, K.W.

    1991-01-01

    Because of substantial portion of the sulfur in Illinois coal is organic, microbial desulfurization of sulfidic and thiophenic functionalities could hold great potential for completing pyritic sulfur removal. We are testing the hypothesis that organic sulfur can be reductively removed as H{sub 2}S through the activities of anaerobic microorganisms. Our objectives for this year include the following: (1) To obtain cultures that will reductively desulfurize thiophenic model compounds. In addition to crude oil enrichments begun last year, we sampled municipal sewage sludge. (2) To continue to work toward optimizing the activity of the DBDS-reducing cultures obtained during the previous year. (3) To expand coal desulfurization work to include other coals including Illinois Basin Coal 101 and a North Dakota lignite, which might be more susceptible to the dibenzyldisulfide reducing cultures due to its lower rank. (4) To address the problem of sulfide sorption, by investigating the sorption capacity of coals in addition to Illinois Basin Coal 108.

  11. An hp symplectic pseudospectral method for nonlinear optimal control

    NASA Astrophysics Data System (ADS)

    Peng, Haijun; Wang, Xinwei; Li, Mingwu; Chen, Biaosong

    2017-01-01

    An adaptive symplectic pseudospectral method based on the dual variational principle is proposed and is successfully applied to solving nonlinear optimal control problems in this paper. The proposed method satisfies the first order necessary conditions of continuous optimal control problems, also the symplectic property of the original continuous Hamiltonian system is preserved. The original optimal control problem is transferred into a set of nonlinear equations which can be solved easily by Newton-Raphson iterations, and the Jacobian matrix is found to be sparse and symmetric. The proposed method, on one hand, exhibits exponent convergence rates when the number of collocation points are increasing with the fixed number of sub-intervals; on the other hand, exhibits linear convergence rates when the number of sub-intervals is increasing with the fixed number of collocation points. Furthermore, combining with the hp method based on the residual error of dynamic constraints, the proposed method can achieve given precisions in a few iterations. Five examples highlight the high precision and high computational efficiency of the proposed method.

  12. Seven health physics calculator programs for the HP-41CV

    SciTech Connect

    Rittmann, P.D.

    1984-08-01

    Several user-oriented programs for the Hewlett-Packard HP-41CV are explained. The first program builds, stores, alters, and ages a list of radionuclides. This program only handles single- and double-decay chains. The second program performs convenient conversions for the six nuclides of concern in plutonium handling. The conversions are between mass, activity, and weight percents of the isotopes. The source can be aged and/or neutron generation rates can be computed. The third program is a timekeeping program that improves the process of manually estimating and tracking personnel exposure during high dose rate tasks by replacing the pencil, paper, and stopwatch method. This program requires a time module. The remaining four programs deal with computations of time-integrated air concentrations at various distances from an airborne release. Building wake effects, source depletion by ground deposition, and sector averaging can all be included in the final printout of the X/Q - Hanford and X/Q - Pasquill programs. The shorter versions of these, H/Q and P/Q, compute centerline or sector-averaged values and include a subroutine to facilitate dose estimation by entering dose factors and quantities released. The horizontal and vertical dispersion parameters in the Pasquill-Gifford programs were modeled with simple, two-parameter functions that agreed very well with the usual textbook graphs. 8 references, 7 appendices.

  13. Preparation of WO3/g-C3N4 composites and their application in oxidative desulfurization

    NASA Astrophysics Data System (ADS)

    Zhao, Rongxiang; Li, Xiuping; Su, Jianxun; Gao, Xiaohan

    2017-01-01

    WO3/graphitic carbon nitride (g-C3N4) composites were successfully synthesized through direct calcining of a mixture of WO3 and g-C3N4 at 400 °C for 2 h. The WO3 was prepared by calcination of phosphotungstic acid at 550 °C for 4 h, and the g-C3N4 was obtained by calcination of melamine at 520 °C for 4 h. The WO3/g-C3N4 composites were characterized by X-ray diffraction (XRD), Scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FT-IR), and Brunner-Emmett-Teller analysis (BET). The WO3/g-C3N4 composites exhibited stronger XRD peaks of WO3 and g-C3N4 than the WO3 and pure g-C3N4. In addition, two WO3 peaks at 25.7° and 26.6° emerged for the 36% -WO3/g-C3N4 composite. This finding indicated that WO3 was highly dispersed on the surface of the g-C3N4 nanosheets and interacted with the nanosheets, which resulted in the appearance of (012) and (022) planes of WO3. The WO3/g-C3N4 composite also exhibited a larger specific surface area and higher degree of crystallization than WO3 or pure g-C3N4, which resulted in high catalytic activity of the catalyst. Desulfurization experiments demonstrated that the desulfurization rate of dibenzothiophene (DBT) in model oil reached 91.2% under optimal conditions. Moreover, the activity of the catalyst was not significantly decreased after five recycles.

  14. Advanced Flue Gas Desulfurization (AFGD) demonstration project: Volume 2, Project performance and economics. Final technical report

    SciTech Connect

    1996-04-30

    The project objective is to demonstrate removal of 90--95% or more of the SO{sub 2} at approximately one-half the cost of conventional scrubbing technology; and to demonstrate significant reduction of space requirements. In this project, Pure Air has built a single SO{sub 2} absorber for a 528-MWe power plant. The absorber performs three functions in a single vessel: prequencher, absorber, and oxidation of sludge to gypsum. Additionally, the absorber is of a co- current design, in which the flue gas and scrubbing slurry move in the same direction and at a relatively high velocity compared to conventional scrubbers. These features all combine to yield a state- of-the-art SO{sub 2} absorber that is more compact and less expensive than conventional scrubbers. The project incorporated a number of technical features including the injection of pulverized limestone directly into the absorber, a device called an air rotary sparger located within the base of the absorber, and a novel wastewater evaporation system. The air rotary sparger combines the functions of agitation and air distribution into one piece of equipment to facilitate the oxidation of calcium sulfite to gypsum. Additionally, wastewater treatment is being demonstrated to minimize water disposal problems inherent in many high-chloride coals. Bituminous coals primarily from the Indiana, Illinois coal basin containing 2--4.5% sulfur were tested during the demonstration. The Advanced Flue Gas Desulfurization (AFGD) process has demonstrated removal of 95% or more of the SO{sub 2} while providing a commercial gypsum by-product in lieu of solid waste. A portion of the commercial gypsum is being agglomerated into a product known as PowerChip{reg_sign} gypsum which exhibits improved physical properties, easier flowability and more user friendly handling characteristics to enhance its transportation and marketability to gypsum end-users.

  15. Assessment of four calculation methods proposed by the EC for waste hazardous property HP 14 'Ecotoxic'.

    PubMed

    Hennebert, Pierre; Humez, Nicolas; Conche, Isabelle; Bishop, Ian; Rebischung, Flore

    2016-02-01

    Legislation published in December 2014 revised both the List of Waste (LoW) and amended Appendix III of the revised Waste Framework Directive 2008/98/EC; the latter redefined hazardous properties HP 1 to HP 13 and HP 15 but left the assessment of HP 14 unchanged to allow time for the Directorate General of the Environment of the European Commission to complete a study that is examining the impacts of four different calculation methods for the assessment of HP 14. This paper is a contribution to the assessment of the four calculation methods. It also includes the results of a fifth calculation method; referred to as "Method 2 with extended M-factors". Two sets of data were utilised in the assessment; the first (Data Set #1) comprised analytical data for 32 different waste streams (16 hazardous (H), 9 non-hazardous (NH) and 7 mirror entries, as classified by the LoW) while the second data set (Data Set #2), supplied by the eco industries, comprised analytical data for 88 waste streams, all classified as hazardous (H) by the LoW. Two approaches were used to assess the five calculation methods. The first approach assessed the relative ranking of the five calculation methods by the frequency of their classification of waste streams as H. The relative ranking of the five methods (from most severe to less severe) is: Method 3>Method 1>Method 2 with extended M-factors>Method 2>Method 4. This reflects the arithmetic ranking of the concentration limits of each method when assuming M=10, and is independent of the waste streams, or the H/NH/Mirror status of the waste streams. A second approach is the absolute matching or concordance with the LoW. The LoW is taken as a reference method and the H wastes are all supposed to be HP 14. This point is discussed in the paper. The concordance for one calculation method is established by the number of wastes with identical classification by the considered calculation method and the LoW (i.e. H to H, NH to NH). The discordance is

  16. Preparation, characterization, and evaluation in vivo of Ins-SiO₂-HP55 (insulin-loaded silica coating HP55) for oral delivery of insulin.

    PubMed

    Zhao, Xiuhua; Shan, Chang; Zu, Yuangang; Zhang, Ying; Wang, Weiguo; Wang, Kunlun; Sui, Xiaoyu; Li, Ruiqiang

    2013-09-15

    Insulin is the most effective and durable drug in the treatment of advanced stage diabetes. However, oral delivering insulin was a tough task for rapid enzymatic degradation. In this work, we designed and developed a delivery system composed of enteric nanosphere for oral delivery of insulin. The silica was selected for loading insulin, which surface has a lot of pores with a powerful adsorption capacity, advantages for permeability and slow-release. The insulin-loaded silica (Ins-SiO2) was prepared by adsorption in HCl solution. The Ins-SiO2 obtained was coated with the hydroxypropyl methylcellulose phthalate (HP55) by desolvation method, which is a good enteric coating material. The Ins-SiO2-HP55, an enteric nanosphere of insulin obtained were characterized by transmission electron microscope (TEM), surface area, Fourier-transform infrared (FT-IR), X-ray diffraction (XRD), differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The results showed that insulin was loaded most in the pores of silica, while the HP55 coated on the extent of Ins-SiO2. In vitro drug release results revealed that the release of insulin from Ins-SiO2-HP55 was markedly reduced in simulated gastric fluid (SGF). By contrast, the release amount of insulin from Ins-SiO2-HP55 was increased significantly in simulated intestinal fluid (SIF). In vivo evaluation on diabetic animals showed the blood glucose level of diabetic rats could be effectively reduced after oral administration Ins-SiO2-HP55. There is marked hypoglycemic effect after 1h of taking the Ins-SiO2-HP55. After 3h, the GLU of rats of the Ins-SiO2-HP55 stably kept from 4.85 to 2.67 mmol/L that was significantly less than the normal level (6.7 mmol/L). However, that of rats taking raw insulin kept from 8.03 to 6.56 mmol/L that is higher than the normal level. These results suggested that Ins-SiO2-HP55 could have potential value in oral administration systems of diabetes chemotherapy.

  17. Desulfurization with a modified limestone formulation in an industrial CFBC boiler

    SciTech Connect

    Young Goo Park; Seung Ho Kim

    2006-02-01

    This work presents a practical result of experimental investigation of the limestone particle size effect on de-SOx from a circulating fluidized bed combustion (CFBC) boiler that burns domestic anthracite and is the first industrial scale in Korea. Because of combustion problems such as clinker formation, fine limestone has not been used as a desulfurization agent. The present test, however, showed that higher content (up to 50%) of the particles under 0.1 mm did not entail any malfunction in a modern CFBC system. In addition, the desulfurization efficiency was found to be comparable to the old mode of limestone sorbents. 17 refs., 4 figs., 3 tabs.

  18. Effect of Slag Chemistry on the Desulfurization Kinetics in Secondary Refining Processes

    NASA Astrophysics Data System (ADS)

    Kang, Jin Gyu; Shin, Jae Hong; Chung, Yongsug; Park, Joo Hyun

    2017-03-01

    Desulfurization behavior was investigated based on a wide slag composition and working temperature range. Moreover, the rate-controlling step (RCS) for desulfurization with regard to the ladle-refining conditions and the transition of the RCS by changing the slag composition was systematically discussed. The desulfurization ratio reached an equilibrium value within approximately 15 minutes irrespective of the CaO/Al2O3 (=C/A = 1.3 to 1.9) and CaO/SiO2 (=C/S = 3.8 to 6.3) ratios. However, the desulfurization behavior of less basic slags (C/A = 1.1 or C/S = 1.9) exhibited a relatively sluggish [S]-decreasing rate as a function of time. The equilibrium S partition ratio increased with an increase in slag basicity (C/A and C/S ratio), not only due to an increase in sulfide capacity but also due to a decrease in oxygen activity in the molten steel. There was a good correlation between the calculated and measured S partition ratios at various slag compositions. However, the measured S partition ratio increased by adding 5 pct CaF2, followed by a constant value. Multiphase slag exhibited a relatively slow desulfurization rate compared to that of fully liquid slag, possibly due to a decrease in the effective liquid slag volume, interfacial reaction area, and a relatively slow slag initial melting rate due to a high melting point. The activation energy of the desulfurization process was estimated to be 58.7 kJ/mol, from which it was proposed that the desulfurization reaction of molten steel via CaO-Al2O3-SiO2-MgO-CaF2 ladle slag was generally controlled by the mass transfer of sulfur in the metal phase. However, there was a transitional period associated with the rate-controlling mechanism due to a change in the physicochemical properties of the slag. For slag with a viscosity greater than about 1.1 dPa·s and an equilibrium S partition ratio lower than about 400, the overall mass-transfer coefficient was affected by the slag properties. Hence, it was theoretically and

  19. Role of the Epigenetic Regulator HP1γ in the Control of Embryonic Stem Cell Properties

    PubMed Central

    Caillier, Maïa; Thénot, Sandrine; Tribollet, Violaine; Birot, Anne-Marie; Samarut, Jacques; Mey, Anne

    2010-01-01

    The unique properties of embryonic stem cells (ESC) rely on long-lasting self-renewal and their ability to switch in all adult cell type programs. Recent advances have shown that regulations at the chromatin level sustain both ESC properties along with transcription factors. We have focused our interest on the epigenetic modulator HP1γ (Heterochromatin Protein 1, isoform γ) that binds histones H3 methylated at lysine 9 (meH3K9) and is highly plastic in its distribution and association with the transcriptional regulation of specific genes during cell fate transitions. These characteristics of HP1γ make it a good candidate to sustain the ESC flexibility required for rapid program changes during differentiation. Using RNA interference, we describe the functional role of HP1γ in mouse ESC. The analysis of HP1γ deprived cells in proliferative and in various differentiating conditions was performed combining functional assays with molecular approaches (RT-qPCR, microarray). We show that HP1γ deprivation slows down the cell cycle of ESC and decreases their resistance to differentiating conditions, rendering the cells poised to differentiate. In addition, HP1γ depletion hampers the differentiation to the endoderm as compared with the differentiation to the neurectoderm or the mesoderm. Altogether, our results reveal the role of HP1γ in ESC self-renewal and in the balance between the pluripotent and the differentiation programs. PMID:21085495

  20. Dynamics of the HP1β-PCNA-containing complexes in DNA replication and repair.

    PubMed

    Trembecka-Lucas, Dominika O; Szczurek, Aleksander T; Dobrucki, Jurek W

    2013-01-01

    Heterochromatin protein 1 (HP1), a small non-histone chromosomal protein, was recently shown to form a complex in vivo with Proliferating Cell Nuclear Antigen (PCNA), a key factor in DNA replication. The complex, which requires HP1β in a form of a dimer, is engaged in DNA repair and replication. We now provide further evidence based on FRET-FLIM live cell studies confirming the association and close proximity between HP1β and PCNA in the complex. We also demonstrate using FRAP, that although HP1β-PCNA complexes are highly mobile in nonreplicating nuclei, when engaged in DNA replication, they become bound and do not exchange with the mobile pool. These observations are in agreement with a notion that a subpopulation of HP1 molecules interact with PCNA in vivo during DNA replication. Similarly, HP1β which is associated with PCNA in regions of DNA repair, is bound and does not exchange with the mobile pool, suggesting that HP1β in association with PCNA may be a component of a DNA repair complex.

  1. Position Determination with LORAN-C Triplets and the Hewlett-Packard HP-41CV Programmable Calculator.

    DTIC Science & Technology

    1982-09-01

    NAVAL POSTGRADUATE SCHOOL Monterey, California POSITION DETERMINATION WITH LORAN-C TRIPLETS AND THE HEWLETT-PACKARD HP-41CV PROGRAMMABLE CALCULATOR by...HP-41CV PROGRAMMABLE CALCULATOR 6. PERFORMING ORG. REPORT NUMBER 7. AUTHOR(e) 6. CONTRACT O GRANT NUMBER(*) Rex H. Shudd? 9. PERFORMING ORGANIZATION...Hyperbolic Fixing Programmable Calculator Loran-C Radio Positioning HP-41C Navigation Geodetics HP-41CV Position Determination Geodetic Distances

  2. Fully automatic hp-adaptivity for acoustic and electromagnetic scattering in three dimensions

    NASA Astrophysics Data System (ADS)

    Kurtz, Jason Patrick

    We present an algorithm for fully automatic hp-adaptivity for finite element approximations of elliptic and Maxwell boundary value problems in three dimensions. The algorithm automatically generates a sequence of coarse grids, and a corresponding sequence of fine grids, such that the energy norm of the error decreases exponentially with respect to the number of degrees of freedom in either sequence. At each step, we employ a discrete optimization algorithm to determine the refinements for the current coarse grid such that the projection-based interpolation error for the current fine grid solution decreases with an optimal rate with respect to the number of degrees of freedom added by the refinement. The refinements are restricted only by the requirement that the resulting mesh is at most 1-irregular, but they may be anisotropic in both element size h and order of approximation p. While we cannot prove that our method converges at all, we present numerical evidence of exponential convergence for a diverse suite of model problems from acoustic and electromagnetic scattering. In particular we show that our method is well suited to the automatic resolution of exterior problems truncated by the introduction of a perfectly matched layer. To enable and accelerate the solution of these problems on commodity hardware, we include a detailed account of three critical aspects of our implementation, namely an efficient implementation of sum factorization, several efficient interfaces to the direct multi-frontal solver MUMPS, and some fast direct solvers for the computation of a sequence of nested projections.

  3. Catalytic oxidative desulfurization of liquid hydrocarbon fuels using air

    NASA Astrophysics Data System (ADS)

    Sundararaman, Ramanathan

    Conventional approaches to oxidative desulfurization of liquid hydrocarbons involve use of high-purity, expensive water soluble peroxide for oxidation of sulfur compounds followed by post-treatment for removal of oxidized sulfones by extraction. Both are associated with higher cost due to handling, storage of oxidants and yield loss with extraction and water separation, making the whole process more expensive. This thesis explores an oxidative desulfurization process using air as an oxidant followed by catalytic decomposition of sulfones thereby eliminating the aforementioned issues. Oxidation of sulfur compounds was realized by a two step process in which peroxides were first generated in-situ by catalytic air oxidation, followed by catalytic oxidation of S compounds using the peroxides generated in-situ completing the two step approach. By this technique it was feasible to oxidize over 90% of sulfur compounds present in real jet (520 ppmw S) and diesel (41 ppmw S) fuels. Screening of bulk and supported CuO based catalysts for peroxide generation using model aromatic compound representing diesel fuel showed that bulk CuO catalyst was more effective in producing peroxides with high yield and selectivity. Testing of three real diesel fuels obtained from different sources for air oxidation over bulk CuO catalyst showed different level of effectiveness for generating peroxides in-situ which was consistent with air oxidation of representative model aromatic compounds. Peroxides generated in-situ was then used as an oxidant to oxidize sulfur compounds present in the fuel over MoO3/SiO2 catalyst. 81% selectivity of peroxides for oxidation of sulfur compounds was observed on MoO3/SiO2 catalyst at 40 °C and under similar conditions MoO3/Al2O3 gave only 41% selectivity. This difference in selectivity might be related to the difference in the nature of active sites of MoO3 on SiO2 and Al2O 3 supports as suggested by H2-TPR and XRD analyses. Testing of supported and bulk Mg

  4. Chemical and physical properties of dry flue gas desulfurization products.

    PubMed

    Kost, David A; Bigham, Jerry M; Stehouwer, Richard C; Beeghly, Joel H; Fowler, Randy; Traina, Samuel J; Wolfe, William E; Dick, Warren A

    2005-01-01

    Beneficial and environmentally safe recycling of flue gas desulfurization (FGD) products requires detailed knowledge of their chemical and physical properties. We analyzed 59 dry FGD samples collected from 13 locations representing four major FGD scrubbing technologies. The chemistry of all samples was dominated by Ca, S, Al, Fe, and Si and strong preferential partitioning into the acid insoluble residue (i.e., coal ash residue) was observed for Al, Ba, Be, Cr, Fe, Li, K, Pb, Si, and V. Sulfur, Ca, and Mg occurred primarily in water- or acid-soluble forms associated with the sorbents or scrubber reaction products. Deionized water leachates (American Society for Testing and Materials [ASTM] method) and dilute acetic acid leachates (toxicity characteristic leaching procedure [TCLP] method) had mean pH values of >11.2 and high mean concentrations of S primarily as SO(2-)4 and Ca. Concentrations of Ag, As, Ba, Cd, Cr, Hg, Pb, and Se (except for ASTM Se in two samples) were below drinking water standards in both ASTM and TCLP leachates. Total toxicity equivalents (TEQ) of dioxins, for two FGD products used for mine reclamation, were 0.48 and 0.53 ng kg(-1). This was similar to the background level of the mine spoil (0.57 ng kg(-1)). The FGD materials were mostly uniform in particle size. Specific surface area (m2 g(-1)) was related to particle size and varied from 1.3 for bed ash to 9.5 for spray dryer material. Many of the chemical and physical properties of these FGD samples were associated with the quality of the coal rather than the combustion and SO2 scrubbing processes used.

  5. Flue gas desulfurization by rotating beds. Final technical report

    SciTech Connect

    Gardner, N.; Keyvani, M.; Coskundeniz, A.

    1992-12-01

    The operating and mass transfer characteristics of rotating foam metal beds were studied to determine the potential for flue gas desulfurization. This is a final technical report on the work supported by DOE {number_sign}FG22-87-PC79924. The report is divided into two sections, Part 1 deals primarily with the operating characteristics of rotating beds, and Part 2 covers the mass transfer characteristics of S0{sub 2} absorption in water-lime slurries. Rotating foam metal beds are in essence packed towers operated in high gravitational fields. The foam metal bed is in the form of a cylindrical donut, or torus, and is rotated to produced the high centrifugal forces. The liquid phase enters the bed at the inner surface of the torus and is pulled by the field through the bed. Gas flows countercurrent to the liquid. The bed packing can have a very large specific surface areas and not flood. Possible benefits include much smaller height of a transfer unit resulting in smaller equipment and supporting structures, reduced solvent inventory, faster response with improved process control, reduced pressure drop, and shorter startup and shut-down times. This work is concerned broadly with the operating characteristics of rotating beds, the objectives being to (1) determine the pressure drop through the rotating bed; (2) determine the power required to operate the beds, (3) investigate the residence time distribution of the liquid phase in the beds; and (4) determine the mass transfer coefficients of S0{sub 2} absorption. Three packings of differing specific surface areas were studied, with areas ranging from 656 to 2952 m{sub 2}/m{sub 3}. Liquid flow rates to 36 kg/s*m{sub 2}, gas flow rate to 2.2 kg/s*m{sub 2}, and gravitational fields to 300 g were covered in this study.

  6. Analytical chemistry of the citrate process for flue gas desulfurization

    SciTech Connect

    Marchant, W.N.; May, S.L.; Simpson, W.W.; Winter, J.K.; Beard, H.R.

    1980-01-01

    The citrate process for flue gas desulfurization (FGD) is a product of continuing research by the US Bureau of Mines to meet the goal of minimizing the objectionable effects of minerals industry operations upon the environment. The reduction of SO/sub 2/ in solution by H/sub 2/S to produce elemental sulfur by the citrate process is extremely complex and results in solutions that contain at least nine different sulfur species. Process solution analysis is essential to a clear understanding of process chemistry and its safe, efficient operation. The various chemical species, the approximate ranges of their concentrations in citrate process solutions, and the analytical methods evolved to determine them are hydrogen sulfide (approx. 0M to 0.06M) by specific ion electrode, polysulfides (unknown) by ultraviolet (uv) spectrophotometry, elemental sulfur (approx. 0M to approx. 0.001M dissolved, approx. 0M to approx. 0.1M suspended) by uv spectrophotometry, thiosulfate (approx. 0M to approx. 0.25M) by iodometry or high performance liquid chromatography (HPLC), polythionates (approx. 0M to approx. 0.01M) by thin layer chromatography (TLC), dithionite (searched for but not detected in process solutions) by polarography or TLC, bisulfite (approx. 0M to 0.2M) by iodometry, sulfate (approx. 0M to 1M) by a Bureau-developed gravimetric procedure, citric acid (approx. 0M to 0.5M) by titration or visible colorimetry, glycolic acid (approx. 0M to 1M) by HPLC, sodium (approx. 1.5M) by flame photometry, and chloride by argentometric titration.

  7. ENHANCED CONTROL OF MERCURY BY WET FLUE GAS DESULFURIZATION SYSTEMS

    SciTech Connect

    G. Blythe; B. Marsh; S. Miller; C. Richardson; M. Richardson

    2001-06-01

    The U.S. Department of Energy and EPRI have co-funded this project to improve the control of mercury emissions from coal-fired power plants equipped with wet flue gas desulfurization (FGD) systems. The project investigated catalytic oxidation of vapor-phase elemental mercury to a form that is more effectively captured in wet FGD systems. If successfully developed, the process could be applicable to over 90,000 MW of utility generating capacity with existing FGD systems and to future FGD installations. Field tests have been conducted to determine whether candidate catalyst materials remain active towards mercury oxidation after extended flue gas exposure. Catalyst life will have a large impact on the cost effectiveness of this potential process. A mobile catalyst test unit has been used to test the activity of four different catalyst materials for a period of up to six months at each of three utility sites. Catalyst testing was completed at the first site, which fires Texas lignite, in December 1998 and at the second test site, which fires a Powder River Basin subbituminous coal in the fall of 1999. Testing at the third site, which fires a medium- to high-sulfur bituminous coal, began in June 2000 and was completed at the end of January 2001. This Topical Reports includes results from Site 3; results from Sites 1 and 2 were reported previously. At Site 3, catalysts were tested in two forms, including powders dispersed in sand bed reactors and in a commercially available form as a coated honeycomb structure. Field testing has been supported by laboratory tests to screen catalysts for activity at specific flue gas compositions, to investigate catalyst deactivation mechanisms and methods for regenerating spent catalysts. Laboratory results related to the Site 3 field effort are also included and discussed in this Topical Report.

  8. ENHANCED CONTROL OF MERCURY BY WET FLUE GAS DESULFURIZATION SYSTEMS

    SciTech Connect

    Unknown

    2001-06-01

    The U.S. Department of Energy and EPRI co-funded this project to improve the control of mercury emissions from coal-fired power plants equipped with wet flue gas desulfurization (FGD) systems. The project has investigated catalytic oxidation of vapor-phase elemental mercury to a form that is more effectively captured in wet FGD systems. If successfully developed, the process could be applicable to over 90,000 MW of utility generating capacity with existing FGD systems, and to future FGD installations. Field tests were conducted to determine whether candidate catalyst materials remain active towards mercury oxidation after extended flue gas exposure. Catalyst life will have a large impact on the cost effectiveness of this potential process. A mobile catalyst test unit was used to test the activity of four different catalyst materials for a period of up to six months each at three utility sites. Catalyst testing was completed at the first site, which fires Texas lignite, in December 1998; at the second test site, which fires a Powder River Basin subbituminous coal, in November 1999; and at the third site, which fires a medium- to high-sulfur bituminous coal, in January 2001. Results of testing at each of the three sites were reported in previous technical notes. At Site 1, catalysts were tested only as powders dispersed in sand bed reactors. At Sites 2 and 3, catalysts were tested in two forms, including powders dispersed in sand and in commercially available forms such as extruded pellets and coated honeycomb structures. This final report summarizes and presents results from all three sites, for the various catalyst forms tested. Field testing was supported by laboratory tests to screen catalysts for activity at specific flue gas compositions, to investigate catalyst deactivation mechanisms and methods for regenerating spent catalysts. Laboratory results are also summarized and discussed in this report.

  9. Shawnee flue gas desulfurization computer model users manual

    SciTech Connect

    Sudhoff, F.A.; Torstrick, R.L.

    1985-03-01

    In conjunction with the US Enviromental Protection Agency sponsored Shawnee test program, Bechtel National, Inc., and the Tennessee Valley Authority jointly developed a computer model capable of projecting preliminary design and economics for lime- and limestone-scrubbing flue gas desulfurization systems. The model is capable of projecting relative economics for spray tower, turbulent contact absorber, and venturi-spray tower scrubbing options. It may be used to project the effect on system design and economics of variations in required SO/sub 2/ removal, scrubber operating parameters (gas velocity, liquid-to-gas (L/G) ration, alkali stoichiometry, liquor hold time in slurry recirculation tanks), reheat temperature, and scrubber bypass. It may also be used to evaluate alternative waste disposal methods or additives (MgO or adipic acid) on costs for the selected process. Although the model is not intended to project the economics of an individual system to a high degree of accuracy, it allows prospective users to quickly project comparative design and costs for limestone and lime case variations on a common design and cost basis. The users manual provides a general descripton of the Shawnee FGD computer model and detailed instructions for its use. It describes and explains the user-supplied input data which are required such as boiler size, coal characteristics, and SO/sub 2/ removal requirments. Output includes a material balance, equipment list, and detailed capital investment and annual revenue requirements. The users manual provides information concerning the use of the overall model as well as sample runs to serve as a guide to prospective users in identifying applications. The FORTRAN-based model is maintained by TVA, from whom copies or individual runs are available. 25 refs., 3 figs., 36 tabs.

  10. Desulfurization of dibenzothiophene (DBT) by a novel strain Lysinibacillus sphaericus DMT-7 isolated from diesel contaminated soil.

    PubMed

    Bahuguna, Ashutosh; Lily, Madhuri K; Munjal, Ashok; Singh, Ravindra N; Dangwal, Koushalya

    2011-01-01

    A new bacterial strain DMT-7 capable of selectively desulfurizing dibenzothiophene (DBT) was isolated from diesel contaminated soil. The DMT-7 was characterized and identified as Lysinibacillus sphaericus DMT-7 (NCBI GenBank Accession No. GQ496620) using 16S rDNA gene sequence analysis. The desulfurized product of DBT, 2-hydroxybiphenyl (2HBP), was identified and confirmed by high performance liquid chromatography analysis and gas chromatography-mass spectroscopy analysis respectively. The desulfurization kinetics revealed that DMT-7 started desulfurization of DBT into 2HBP after the lag phase of 24 hr, exponentially increasing the accumulation of 2HBP up to 15 days leading to approximately 60% desulfurization of the DBT. However, further growth resulted into DBT degradation. The induced culture of DMT-7 showed shorter lag phase of 6 hr and early onset of stationary phase within 10 days for desulfurization as compared to that of non-induced culture clearly indicating the inducibility of the desulfurization pathway of DMT-7. In addition, Lysinibacillus sphaericus DMT-7 also possess the ability to utilize broad range of substrates as sole source of sulfur such as benzothiophene, 3,4-benzo DBT, 4,6-dimethyl DBT, and 4,6-dibutyl DBT. Therefore, Lysinibacillus sphaericus DMT-7 could serve as model system for efficient biodesulfurization of diesel and petrol.

  11. HELICOBACTER PYLORI (HP) INFECTION IN OBESE PATIENTS UNDERGOING ROUXEN- Y GASTRIC BYPASS; EFFICACY OF TWO DIFFERENT TREATMENT REGIMENS IN HP ERADICATION.

    PubMed

    Cuesta Hernández, Martín; Pérez Peña, Celia; Matía Martín, Pilar; Cabrerizo García, Lucio; Pérez-Ferre, Natalia; Sánchez-Pernaute, Andrés; Torres García, Antonio; Rubio Herrera, Miguel Ángel

    2015-08-01

    Introducción: las causas implicadas en el aumento de incidencia de úlcera gástrica tras el bypass en Y de Roux no son completamente conocidas. El tratamiento de la infección por HP se recomienda antes de la cirugía en países cuya prevalencia sea elevada, como el caso de España, de cara a disminuir dicha complicación. Sin embargo, las pautas actuales de tratamiento pueden no ser adecuadas dados los elevados índices de resistencia. Pacientes y métodos: análisis retrospectivo de 243 pacientes operados de bypass en Y de Roux. De ellos, 111 pacientes (45%) presentaban infección por HP. Objetivo principal: comparación de la eficacia de dos terapias de erradicación de la infección por HP. Resultados: 70 pacientes recibieron OCA( Omeprazol 20 mg/12 h, Claritromicina 500 mg/12 h y Amoxicilina 1 g/12h durante 10 días), mientras que 41 pacientes recibieron OLA (Omeprazol 20 mg/12 h, Levofloxacino 500 mg/12 h y Amoxicilina 1 g/12 h durante 10 días). En 56/70 pacientes (80%) que recibieron OCA HP fue erradicado, comparado con 37/41 (91%) del grupo que recibió OLA como primera terapia (p = 0,283). La terapia con OLA usada de segunda línea fue eficaz en 13/14 pacientes con HP resistente a la terapia OCA. Conclusión: la resistencia de HP a Claritromicina es significativa en nuestra serie de pacientes, siendo la terapia con OLA una alternativa adecuada en las cepas resistentes.

  12. An HP1 isoform-specific feedback mechanism regulates Suv39h1 activity under stress conditions.

    PubMed

    Raurell-Vila, Helena; Bosch-Presegue, Laia; Gonzalez, Jessica; Kane-Goldsmith, Noriko; Casal, Carmen; Brown, Jeremy P; Marazuela-Duque, Anna; Singh, Prim B; Serrano, Lourdes; Vaquero, Alejandro

    2017-02-01

    The presence of H3K9me3 and heterochromatin protein 1 (HP1) are hallmarks of heterochromatin conserved in eukaryotes. The spreading and maintenance of H3K9me3 is effected by the functional interplay between the H3K9me3-specific histone methyltransferase Suv39h1 and HP1. This interplay is complex in mammals because the three HP1 isoforms, HP1α, β, and γ, are thought to play a redundant role in Suv39h1-dependent deposition of H3K9me3 in pericentric heterochromatin (PCH). Here, we demonstrate that despite this redundancy, HP1α and, to a lesser extent, HP1γ have a closer functional link to Suv39h1, compared to HP1β. HP1α and γ preferentially interact in vivo with Suv39h1, regulate its dynamics in heterochromatin, and increase Suv39h1 protein stability through an inhibition of MDM2-dependent Suv39h1-K87 polyubiquitination. The reverse is also observed, where Suv39h1 increases HP1α stability compared HP1β and γ. The interplay between Suv39h1 and HP1 isoforms appears to be relevant under genotoxic stress. Specifically, loss of HP1α and γ isoforms inhibits the upregulation of Suv39h1 and H3K9me3 that is observed under stress conditions. Reciprocally, Suv39h1 deficiency abrogates stress-dependent upregulation of HP1α and γ, and enhances HP1β levels. Our work defines a specific role for HP1 isoforms in regulating Suv39h1 function under stress via a feedback mechanism that likely regulates heterochromatin formation.

  13. Helicobacter pylori Secreted Protein HP1286 Triggers Apoptosis in Macrophages via TNF-Independent and ERK MAPK-Dependent Pathways

    PubMed Central

    Tavares, Raquel; Pathak, Sushil Kumar

    2017-01-01

    Macrophages constitute a powerful line of defense against H. pylori. The final disease outcome is highly dependent on the bacterial ability to modulate the effector functions of activated macrophages. Here, we report that H. pylori secreted protein HP1286 is a novel regulator of macrophage responses. Differential expression and release of HP1286 homologues were observed among H. pylori strains. Recombinant purified HP1286 (rHP1286) had the ability to bind to primary human monocyte-derived macrophages (MDM) and macrophage cell lines. Exposure to rHP1286 induced apoptosis in macrophages in a dose- and time-dependent manner. Although interaction of rHP1286 was observed for several other cell types, such as human monocytes, differentiated neutrophil-like HL60 cells, and the T lymphocyte Jurkat cell line, rHP1286 failed to induce apoptosis under similar conditions, indicating a macrophage-specific effect of the protein. A mutant strain of H. pylori lacking HP1286 protein expression was significantly impaired in its ability to induce apoptosis in macrophages. Significantly higher caspase 3 activity was detected in rHP1286-challenged macrophages. Furthermore, rHP1286-induced macrophages apoptosis was not inhibited in the presence of neutralizing antibodies against TNF. These observations indicate that rHP1286 induced a caspase-dependent and TNF-independent macrophage apoptosis. Pre-treatment of macrophages with U0126, an inhibitor of the ERK MAPK signaling pathway significantly reduced rHP1286-induced apoptosis. Furthermore, nuclear translocation of ERK and phosphorylation of c-Fos was detected in rHP1286-treated macrophages. These results provide functional insight into the potential role of HP1286 during H. pylori infection. Considering the ability of HP1286 to induce macrophage apoptosis, the protein could possibly help in the bacterial escape from the activated macrophages and persistence in the stomach. PMID:28293545

  14. HP1-Assisted Aurora B Kinase Activity Prevents Chromosome Segregation Errors.

    PubMed

    Abe, Yusuke; Sako, Kosuke; Takagaki, Kentaro; Hirayama, Youko; Uchida, Kazuhiko S K; Herman, Jacob A; DeLuca, Jennifer G; Hirota, Toru

    2016-03-07

    Incorrect attachment of kinetochore microtubules is the leading cause of chromosome missegregation in cancers. The highly conserved chromosomal passenger complex (CPC), containing mitotic kinase Aurora B as a catalytic subunit, ensures faithful chromosome segregation through destabilizing incorrect microtubule attachments and promoting biorientation of chromosomes on the mitotic spindle. It is unknown whether CPC dysfunction affects chromosome segregation fidelity in cancers and, if so, how. Here, we show that heterochromatin protein 1 (HP1) is an essential CPC component required for full Aurora B activity. HP1 binding to the CPC becomes particularly important when Aurora B phosphorylates kinetochore targets to eliminate erroneous microtubule attachments. Remarkably, a reduced proportion of HP1 bound to CPC is widespread in cancers, which causes an impairment in Aurora B activity. These results indicate that HP1 is an essential modulator for CPC function and identify a molecular basis for chromosome segregation errors in cancer cells.

  15. 22. ASSEMBLY OF 9700 H.P. ALLIS CHALMERS TURBINE, CENTERVILLE P.H. ...

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

    22. ASSEMBLY OF 9700 H.P. ALLIS CHALMERS TURBINE, CENTERVILLE P.H. Drawing no. 50153, traced from Allis Chalmers drawing #699, April 24, 1906. - Centerville Hydroelectric System, Powerhouse, Butte Creek, Centerville, Butte County, CA

  16. Laplace and Z Transform Solutions of Differential and Difference Equations With the HP-41C.

    ERIC Educational Resources Information Center

    Harden, Richard C.; Simons, Fred O., Jr.

    1983-01-01

    A previously developed program for the HP-41C programmable calculator is extended to handle models of differential and difference equations with multiple eigenvalues. How to obtain difference equation solutions via the Z transform is described. (MNS)

  17. LOOKING DOWN ON GENERAL ELECTRIC 250HP SYNCHRONOUS MOTOR. LARGE HANDWHEEL ...

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

    LOOKING DOWN ON GENERAL ELECTRIC 250-HP SYNCHRONOUS MOTOR. LARGE HANDWHEEL IN FOREGROUND USED TO TIGHTEN BRAKE BAND AROUND ARMATURE TO STOP BALL MILL AND MOTOR ROTATION. - Shenandoah-Dives Mill, 135 County Road 2, Silverton, San Juan County, CO

  18. [Comparison of port needle with safety device between Huber Plus (HP) and Poly PERF Safe (PPS)].

    PubMed

    Shimono, Chigusa; Tanaka, Atsuko; Fujita, Ai; Ishimoto, Miki; Oura, Shoji; Yamaue, Hiroki; Sato, Morio

    2010-05-01

    An embedded port is frequently used for outpatients with advanced cancer in central venous chemotherapy or hepatic arterial chemoinfusion. The port needle with a safety device in an ambulatory treatment center is indispensable for medical employees and patient plus family to reduce the risk of a needle puncture accident and to prevent iatrogenic infection. The port needle with safety system has been already introduced in our chemotherapy center. There are two types of port needle with safety device; Huber Plus (HP, Medicon Co., Ltd.) and POLY PERF Safe (PPS, Pyolax Device, Co., Ltd.). The comparison of the feasibility between HP and PPS was conducted by both medical employees and patients plus family using an inquiry score method. HP was highly regarded for its stability plus fixation and PPS for its usefulness in puncture and extraction of the needle. PPS was found to be preferable to HP based on the overall evaluation.

  19. Method and apparatus for enhancing the desulfurization of hot coal gas in a fluid-bed coal gasifier

    DOEpatents

    Grindley, T.

    1988-04-05

    A process and apparatus for providing additional desulfurization of the hot gas produced in a fluid-bed coal gasifier, within the gasifier is described. A fluid-bed of iron oxide is located inside the gasifier above the gasification bed in a fluid-bed coal gasifier in which in-bed desulfurization by lime/limestone takes place. The product gases leave the gasification bed typically at 1600 to 1800 F and are partially quenched with water to 1000 to 1200 F before entering the iron oxide bed. The iron oxide bed provides additional desulfurization beyond that provided by the lime /limestone. 1 fig.

  20. Field studies on the use of flue gas desulfurization (FGD) gypsum in agriculture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Flue gas desulfurization gypsum (FGDG) is a product of precipitation of sulfur from stack gases from coal-fired electric power plants. This material is produced in increasingly large quantities by electric power companies to meet clean air standards. We have evaluated this material for beneficial us...

  1. Bench-scale development of mild gasification char desulfurization. Technical report, 1 March--31 May 1994

    SciTech Connect

    Knight, R.A.

    1994-09-01

    The goal of this project is to scale up a process, developed under a previous ICCI grant, for desulfurization of mild gasification char by treatment with hydrogen-rich process-derived fuel gas at 650--760 C and 7--15 atm. The char can be converted into a low-sulfur metallurgical form coke. In the prior study, IBC-105 coal with 4.0 wt% sulfur was converted to chars with less than 1.0 wt% sulfur in a laboratory-scale batch reactor. The susceptibility of the char to desulfurization was correlated with physicochemical char properties and mild gasification conditions. Acid pretreatment of the coal prior to mild gasification was also shown to significantly enhance subsequent sulfur removal. In this study, IGT is conducting continuous bench-scale tests in a 1-lb/h fluidized-bed reactor to determine the preferred process conditions and obtain steady-state data necessary for process design and scale-up. The desulfurized chars are to be used to produce low-sulfur form coke, which will be evaluated for density, reactivity, and strength properties relevant to utilization in blast furnaces. This quarter, 2,500 g of mild gasification char was produced from untreated IBC-105 coal in the bench-scale reactor. Half of this char will be subjected to sulfuric acid treatment to enhance subsequent desulfurization. Char-producing runs were also initiated with acid-pretreated coal, which will produce about 1,250 g of char.

  2. Synthesis, characterization, and application of 1-butyl-3-methylimidazolium thiocyanate for extractive desulfurization of liquid fuel.

    PubMed

    Dharaskar, Swapnil A; Wasewar, Kailas L; Varma, Mahesh N; Shende, Diwakar Z

    2016-05-01

    1-Butyl-3-methylimidazolium thiocyanate [BMIM]SCN has been presented on extractive desulfurization of liquid fuel. The FTIR, (1)H-NMR, and C-NMR have been discussed for the molecular confirmation of synthesized [BMIM]SCN. Further, thermal, conductivity, moisture content, viscosity, and solubility analyses of [BMIM]SCN were carried out. The effects of time, temperature, sulfur compounds, ultrasonication, and recycling of [BMIM]SCN on removal of dibenzothiophene from liquid fuel were also investigated. In extractive desulfurization, removal of dibenzothiophene in n-dodecane was 86.5 % for mass ratio of 1:1 in 30 min at 30 °C under the mild process conditions. [BMIM]SCN could be reused five times without a significant decrease in activity. Also, in the desulfurization of real fuels, multistage extraction was examined. The data and results provided in the present paper explore the significant insights of imidazolium-based ionic liquids as novel extractant for extractive desulfurization of liquid fuels.

  3. Coal desulfurization by chlorinolysis production and combustion test evaluation of product coals

    NASA Technical Reports Server (NTRS)

    Kalvinskas, J. J.; Daly, D.

    1982-01-01

    Laboratory-scale screening tests were carried out on coal from Harrison County, Ohio to establish chlorination and hydrodesulfurization conditions for the batch reactor production of chlorinolysis and chlorinolysis-hydrodesulfurized coals. In addition, three bituminous coals, were treated on the lab scale by the chlorinolysis process to provide 39 to 62% desulfurization. Two bituminous coals and one subbituminous coal were then produced in 11 to 15 pound lots as chlorinolysis and hydrodesulfurized coals. The chlorinolysis coals had a desulfurization of 29-69%, reductions in voltatiles and hydrogen. Hydrodesulfurization provided a much greater desulfurization (56-86%), reductions in volatiles and hydrogen. The three coals were combustion tested in the Penn State ""plane flame furnace'' to determine ignition and burning characteristics. All three coals burned well to completion as: raw coals, chlorinolysis processed coals, and hydrodesulfurized coals. The hydrodesulfurized coals experienced greater ignition delays and reduced burning rates than the other coals because of the reduced volatile content. It is thought that the increased open pore volume in the desulfurized-devolatilized coals compensates in part for the decreased volatiles effect on ignition and burning.

  4. High Temperature Flue Gas Desulfurization In Moving Beds With Regenerable Copper Based Sorbents

    SciTech Connect

    Cengiz, P.A.; Ho, K.K.; Abbasian, J.; Lau, F.S.

    2002-09-20

    The objective of this study was to develop new and improved regenerable copper based sorbent for high temperature flue gas desulfurization in a moving bed application. The targeted areas of sorbent improvement included higher effective capacity, strength and long-term durability for improved process control and economic utilization of the sorbent.

  5. COMPARISON OF WEST GERMAN AND U.S. FLUE GAS DESULFURIZATION AND SELECTIVE CATALYTIC REDUCTION COSTS

    EPA Science Inventory

    The report documents a comparison of the actual cost retrofitting flue gas desulfurization (FGD) and selective catalytic reduction (SCR) on Federal Republic of German (FRG) boilers to cost estimating procedures used in the U.S. to estimate the retrofit of these controls on U.S. b...

  6. Elemental sulfur-producing high-temperature fuel gas desulfurization process

    SciTech Connect

    Anderson, G.L.; Garrigan, P.C.; Berry, F.O.

    1980-01-01

    Preliminary studies have shown that certain materials when added to air-regenerable, high-temperature, fuel gas desulfurization sorbents, such as iron oxide or zinc oxide, significantly increase elemental sulfur formation during regeneration. Although the full range of conditions under which these materials can be applied remains to be determined, successful applications could eliminate a costly SO/sub 2/ reduction step.

  7. Investigation Of A Mercury Speciation Technique For Flue Gas Desulfurization Materials

    EPA Science Inventory

    Most of the synthetic gypsum generated from wet flue gas desulfurization (FGD) scrubbers is currently being used for wallboard production. Because oxidized mercury is readily captured by the wet FGD scrubber, and coal-fired power plants equipped with wet scrubbers desire to bene...

  8. Comparison of soil applied flue gas desulfurization (FGD) and agricultural gypsum on soil physical properties

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Gypsum can come from different sources. Agricultural gypsum is typically mined and used to supply calcium to crops. Flue gas desulfurization (FGD) gypsum is a by-product of coal power plants. Although their chemical formulas are the same, different trace elements and materials are present in them....

  9. Catalyst for Desulfurization of Industrial Waste Gases and Process for Preparing the Catalyst

    SciTech Connect

    Dupin, T.

    1983-12-27

    Industrial waste gases containing objectionable/polluting compounds of sulfur, e.g., H/sub 2/S, SO/sub 2/ and such organo-sulfur derivatives as COS, CS/sub 2/ and mercaptans, are catalytically desulfurized, e.g., by Claus process, employing an improved catalyst comprising titanium dioxide and calcium, barium, strontium or magnesium sulfate.

  10. Oxidative desulfurization of dibenzothiophene from model oil using ionic liquids as extracting agent

    NASA Astrophysics Data System (ADS)

    Taha, Mohd F.; Atikah, N.; Chong, F. K.; Shaharun, Maizatul S.

    2012-09-01

    The oxidative desulfurization of dibenzothiophene (DBT) from model oil (in n-dodecane) was carried out using ionic liquid as the extractant and catalyst, and hydrogen peroxide (H2O2) in combination with acetic acid (CH3COOH) and sulphuric acid (H2SO4) as the oxidant. The ionic liquids used were 1-butyl-3-methylimidazolium octyl sulphate ([Bmim][OcSO4]) and 1-butyl-3-methylimidazolium acetate ([Bmim][Ac]). The effect of the amounts of H2O2 on oxidative desulphurization of model oil was first investigated without the usage of ionic liquids at room temperature. The results indicate that greater amount of H2O2 give higher desulfurization and the maximum desulfurization in this study, i.e. 34 %, was occurred when the molar ratio of H2O2 to sulfur was 5:1. With the usage of ionic liquid and the molar ratio of 5:1 (H2O2:sulfur), the efficiency of DBT removal from model oil was increased significantly in terms of percent removal and removal time. Ionic liquid of [Bmim][OcSO4] performed better than [Bmim][Ac] with 72 % DBT removal. When molar ratio of H2O2 to sulphur was 5:1, volume ratio of ionic liquid to model oil was 1:1 and mixing time was 60 min at room temperature. The results indicate the potential of ionic liquids as the extractant and catalyst for oxidative desulfurization of hydrocarbon fuels.

  11. Flue gas desulfurization gypsum: Its effectiveness as an alternative bedding material for broiler production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Flue gas desulfurization gypsum (FGDG) may be a viable low-cost alternative bedding material for broiler production. In order to evaluate FGD gypsum’s viability, three consecutive trials were conducted to determine its influence on live performance (body weight, feed consumption, feed efficiency, an...

  12. Decreasing phosphorus loss in tile-drained landscapes using flue gas desulfurization gypsum

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Elevated phosphorus (P) loading from agricultural non-point source pollution continues to impair inland waterbodies throughout the world. The application of flue gas desulfurization (FGD) gypsum to agricultural fields has been suggested to decrease P loading because of its high calcium content and P...

  13. Spectral/HP Element Method With Hierarchical Reconstruction for Solving Hyperbolic Conservation Laws

    SciTech Connect

    Xu, Zhiliang; Lin, Guang

    2009-12-01

    Hierarchical reconstruction (HR) has been successfully applied to prevent oscillations in solutions computed by finite volume, discontinuous Galerkin, spectral volume schemes when solving hyperbolic conservation laws. In this paper, we demonstrate that HR can also be combined with spectral/hp element methods for solving hyperbolic conservation laws. We show that HR preserves the order of accuracy of spectral/hp element methods for smooth solutions and generate essentially non-oscillatory solution profiles for shock wave problems.

  14. In-Plant Protection against Helicoverpa armigera by Production of Long hpRNA in Chloroplasts

    PubMed Central

    Bally, Julia; McIntyre, Glen J.; Doran, Rachel L.; Lee, Karen; Perez, Alicia; Jung, Hyungtaek; Naim, Fatima; Larrinua, Ignacio M.; Narva, Kenneth E.; Waterhouse, Peter M.

    2016-01-01

    Expressing double-stranded RNA (dsRNA) in transgenic plants to silence essential genes within herbivorous pests is referred to as trans-kingdom RNA interference (TK-RNAi) and has emerged as a promising strategy for crop protection. However, the dicing of dsRNA into siRNAs by the plant’s intrinsic RNAi machinery may reduce this pesticidal activity. Therefore, genetic constructs, encoding ∼200 nt duplex-stemmed-hairpin (hp) RNAs, targeting the acetylcholinesterase gene of the cotton bollworm, Helicoverpa armigera, were integrated into either the nuclear or the chloroplast genome of Nicotiana benthamiana. Undiced, full-length hpRNAs accumulated in transplastomic lines of N. benthamiana and conferred strong protection against H. armigera herbivory while the hpRNAs of nuclear-transformed plants were processed into siRNAs and gave more modest anti-feeding activity. This suggests that there is little or no RNAi machinery or activity in the chloroplast, that hpRNAs produced within this organelle do not enter the cytoplasm, and that oral delivery of chloroplast-packaged intact hpRNA is a more effective means of delivering TK-RNAi than using nuclear encoded hpRNAs. This contrasts with a recently reported correlation between siRNA expression and effectiveness of TK-RNAi targeting the chitinase gene of H. armigera, but is consistent with reports of efficient TK-RNAi by dsRNA generated in chloroplasts by converging promoters flanking a pest gene sequence and from very small (21 nt-stem) hpRNAs resembling artificial miRNAs. Here we demonstrate that hpRNAs, constructed along the conventional design principles of plant RNAi constructs but integrated into the chloroplast genome, are stable and effective over multiple generations, and hold the promise of providing durable pest resistance in crops. PMID:27746796

  15. In-Plant Protection against Helicoverpa armigera by Production of Long hpRNA in Chloroplasts.

    PubMed

    Bally, Julia; McIntyre, Glen J; Doran, Rachel L; Lee, Karen; Perez, Alicia; Jung, Hyungtaek; Naim, Fatima; Larrinua, Ignacio M; Narva, Kenneth E; Waterhouse, Peter M

    2016-01-01

    Expressing double-stranded RNA (dsRNA) in transgenic plants to silence essential genes within herbivorous pests is referred to as trans-kingdom RNA interference (TK-RNAi) and has emerged as a promising strategy for crop protection. However, the dicing of dsRNA into siRNAs by the plant's intrinsic RNAi machinery may reduce this pesticidal activity. Therefore, genetic constructs, encoding ∼200 nt duplex-stemmed-hairpin (hp) RNAs, targeting the acetylcholinesterase gene of the cotton bollworm, Helicoverpa armigera, were integrated into either the nuclear or the chloroplast genome of Nicotiana benthamiana. Undiced, full-length hpRNAs accumulated in transplastomic lines of N. benthamiana and conferred strong protection against H. armigera herbivory while the hpRNAs of nuclear-transformed plants were processed into siRNAs and gave more modest anti-feeding activity. This suggests that there is little or no RNAi machinery or activity in the chloroplast, that hpRNAs produced within this organelle do not enter the cytoplasm, and that oral delivery of chloroplast-packaged intact hpRNA is a more effective means of delivering TK-RNAi than using nuclear encoded hpRNAs. This contrasts with a recently reported correlation between siRNA expression and effectiveness of TK-RNAi targeting the chitinase gene of H. armigera, but is consistent with reports of efficient TK-RNAi by dsRNA generated in chloroplasts by converging promoters flanking a pest gene sequence and from very small (21 nt-stem) hpRNAs resembling artificial miRNAs. Here we demonstrate that hpRNAs, constructed along the conventional design principles of plant RNAi constructs but integrated into the chloroplast genome, are stable and effective over multiple generations, and hold the promise of providing durable pest resistance in crops.

  16. The HP0256 gene product is involved in motility and cell envelope architecture of Helicobacter pylori

    PubMed Central

    2010-01-01

    Background Helicobacter pylori is the causative agent for gastritis, and peptic and duodenal ulcers. The bacterium displays 5-6 polar sheathed flagella that are essential for colonisation and persistence in the gastric mucosa. The biochemistry and genetics of flagellar biogenesis in H. pylori has not been fully elucidated. Bioinformatics analysis suggested that the gene HP0256, annotated as hypothetical, was a FliJ homologue. In Salmonella, FliJ is a chaperone escort protein for FlgN and FliT, two proteins that themselves display chaperone activity for components of the hook, the rod and the filament. Results Ablation of the HP0256 gene in H. pylori significantly reduced motility. However, flagellin and hook protein synthesis was not affected in the HP0256 mutant. Transmission electron transmission microscopy revealed that the HP0256 mutant cells displayed a normal flagellum configuration, suggesting that HP0256 was not essential for assembly and polar localisation of the flagella in the cell. Interestingly, whole genome microarrays of an HP0256 mutant revealed transcriptional changes in a number of genes associated with the flagellar regulon and the cell envelope, such as outer membrane proteins and adhesins. Consistent with the array data, lack of the HP0256 gene significantly reduced adhesion and the inflammatory response in host cells. Conclusions We conclude that HP0256 is not a functional counterpart of FliJ in H. pylori. However, it is required for full motility and it is involved, possibly indirectly, in expression of outer membrane proteins and adhesins involved in pathogenesis and adhesion. PMID:20377912

  17. Double pattern EDA solutions for 32nm HP and beyond

    NASA Astrophysics Data System (ADS)

    Bailey, George E.; Tritchkov, Alexander; Park, Jea-Woo; Hong, Le; Wiaux, Vincent; Hendrickx, Eric; Verhaegen, Staf; Xie, Peng; Versluijs, Janko

    2007-03-01

    The fate of optical-based lithography hinges on the ability to deploy viable resolution enhancement techniques (RET). One such solution is double patterning (DP). Like the double-exposure technique, double patterning is a decomposition of the design to relax the pitch that requires dual masks, but unlike double-exposure techniques, double patterning requires an additional develop and etch step, which eliminates the resolution degradation due to the cross-coupling that occurs in the latent images of multiple exposures. This additional etch step is worth the effort for those looking for an optical extension [1]. The theoretical k I for a double-patterning technique of a 32nm half-pitch (HP) design for a 1.35NA 193nm imaging system is 0.44 whereas the k I for a single-exposure technique of this same design would be 0.22 [2], which is sub-resolution. There are other benefits to the DP technique such as the ability to add sub-resolution assist features (SRAF) in the relaxed pitch areas, the reduction of forbidden pitches, and the ability to apply mask biases and OPC without encountering mask constraints. Similarly to AltPSM and SRAF techniques one of the major barriers to widespread deployment of double patterning to random logic circuits is design compliance with split layout synthesis requirements [3]. Successful implementation of DP requires the evolution and adoption of design restrictions by specifically tailored design rules. The deployment of double patterning does spawn a couple of issues that would need addressing before proceeding into a production environment. As with any dual-mask RET application, there are the classical overlay requirements between the two exposure steps and there are the complexities of decomposing the designs to minimize the stitching but to maximize the depth of focus (DoF). In addition, the location of the design stitching would require careful consideration. For example, a stitch in a field region or wider lines is preferred over a

  18. Marinobacter adhaerens HP15 harbors two CzcCBA efflux pumps involved in zinc detoxification.

    PubMed

    Stahl, Antje; Pletzer, Daniel; Mehmood, Amna; Ullrich, Matthias S

    2015-09-01

    Several members of the ubiquitously found γ-proteobacterial genus Marinobacter were described or assumed to inhabit marine environments naturally enriched in heavy metals. However, direct studies that describe the ability of this genus to occupy such environments have not been conducted. To cope with heavy metal stress, bacteria possess specific efflux pumps as tools for detoxification, among which the CzcCBA type efflux system is one representative. Previous studies showed that this system plays an important role in resistance towards cadmium, zinc, and cobalt. Up to now, no study had focused on characterization of Czc pumps in Marinobacter sp. or other marine prokaryotes. Herein, we elucidated the function of two CzcCBA pumps encoded by Marinobacter adhaerens HP15's genome during exposure to cadmium, zinc, and cobalt. Single and double knock-out mutants lacking the corresponding two czcCBA operons were generated and analyzed in terms of their resistance profiles. Both operons appeared to be important for zinc resistance but had no role in tolerance towards cadmium or cobalt. One of the mutations was genetically complemented thereby restoring the wild type phenotype. In accordance with the resistance pattern, expression of the genes coding for both CzcCBA pumps was induced by zinc but neither by cadmium nor cobalt.

  19. Microbial Desulfurization of Alkylated Dibenzothiophenes from a Hydrodesulfurized Middle Distillate by Rhodococcus erythropolis I-19

    PubMed Central

    Folsom, B. R.; Schieche, D. R.; DiGrazia, P. M.; Werner, J.; Palmer, S.

    1999-01-01

    Rhodococcus erythropolis I-19, containing multiple copies of key dsz genes, was used to desulfurize alkylated dibenzothiophenes (Cx-DBTs) found in a hydrodesulfurized middle-distillate petroleum (MD 1850). Initial desulfurization rates of dibenzothiophene (DBT) and MD 1850 by I-19 were 5.0 and 2.5 μmol g dry cell weight−1 min−1, more than 25-fold higher than that for wild-type bacteria. According to sulfur K-edge X-ray absorption near-edge structure (XANES) analysis, thiophenic compounds accounted for >95% of the total sulfur found in MD 1850, predominantly Cx-DBTs and alkylated benzothiophenes. Extensive biodesulfurization resulted in a 67% reduction of total sulfur from 1,850 to 615 ppm S. XANES analysis of the 615-ppm material gave a sulfur distribution of 75% thiophenes, 11% sulfides, 2% sulfoxides, and 12% sulfones. I-19 preferentially desulfurized DBT and C1-DBTs, followed by the more highly alkylated Cx-DBTs. Shifting zero- to first-order (first-order) desulfurization rate kinetics were observed when MD 1850 was diluted with hexadecane. Apparent saturation rate constant (K0) and half-saturation rate constant (K1) values were calculated to be 2.8 μmol g dry cell weight−1 min−1 and 130 ppm, respectively. However, partial biocatalytic reduction of MD 1850 sulfur concentration followed by determination of initial rates with fresh biocatalyst led to a sigmoidal kinetic behavior. A competitive-substrate model suggested that the apparent K1 values for each group of Cx-DBTs increased with increasing alkylation. Overall desulfurization rate kinetics with I-19 were affected by the concentration and distribution of Cx-DBTs according to the number and/or lengths of alkyl groups attached to the basic ring structure. PMID:10543810

  20. Characteristics and reactivity of rapidly hydrated sorbent for semidry flue gas desulfurization

    SciTech Connect

    Jie Zhang; Changfu You; Suwei Zhao; Changhe Chen; Haiying Qi

    2008-03-01

    The semidry flue gas desulfurization (FGD) process has many advantages over the wet FGD process for moving sulfur dioxide emissions from pulverized coal-fired power plants. Semidry FGD with a rapidly hydrated sorbent was studied in a pilot-scale circulating fluidized bed (CFB) experimental facility. The sorbent was made from lumps of lime and coal fly ash. The desulfurization efficiency was measured for various operating parameters, including the sorbent recirculation rate and the water spray method. The experimental results show that the desulfurization efficiencies of the rapidly hydrated sorbent were 1.5-3.0 times higher than a commonly used industrial sorbent for calcium to sulfur molar ratios from 1.2 to 3.0, mainly due to the higher specific surface area and pore volume. The Ca(OH){sub 2} content in the cyclone separator ash was about 2.9% for the rapidly hydrated sorbent and was about 0.1% for the commonly used industrial sorbent, due to the different adhesion between the fine Ca(OH){sub 2} particles and the fly ash particles, and the low cyclone separation efficiency for the fine Ca(OH){sub 2} particles that fell off the sorbent particles. Therefore the actual recirculation rates of the active sorbent with Ca(OH){sub 2} particles were higher for the rapidly hydrated sorbent, which also contributed to the higher desulfurization efficiency. The high fly ash content in the rapidly hydrated sorbent resulted in good operating stability. The desulfurization efficiency with upstream water spray was 10-15% higher than that with downstream water spray. 20 refs., 7 figs., 1 tab.

  1. Advanced sulfur control concepts for hot gas desulfurization technology. Quarterly report, January 1--March 31, 1997

    SciTech Connect

    1997-08-01

    Favorable results were achieved in the sulfidation of CeO{sub 2} by H{sub 2}S and the regeneration of Ce{sub 2}O{sub 2}S by SO{sub 2}. Successful removal of approximately 99% of the H{sub 2}S from the sulfidation gas to levels of about 100 ppmv (or lower), and the production of approximately 12% elemental sulfur (as S{sub 2}) in the regeneration product gas were highlights. Final effort in the preliminary phase included a ten-cycle test at standard sulfidation and regeneration conditions with little or no sorbent deterioration. In the initial test of the detailed experimental phase of the program, the authors investigated the effect of temperature on the regeneration reaction. Results of preliminary tests showed that the Ce{sub 2}O{sub 2}S-SO{sub 2} reaction did not occur at 350 C, and all subsequent regeneration tests were at 600 C where the reaction was rapid. Significant progress has been made on the process analysis effort during the quarter. Detailed process flow diagrams along with material and energy balance calculations for six design case studies were completed in the previous quarter. Two of the cases involved two-stage desulfurization with steam regeneration, three used two-stage desulfurization with SO{sub 2} regeneration, and the sixth was based on single-stage desulfurization with elemental sulfur recovery using the DSRP concept. In the present quarter, major process equipment was sized for each of the six cases. Preliminary annual operating and levelized total cost estimates were then completed for two design cases--one involving two-stage desulfurization with SO{sub 2} regeneration and the second based on single-stage desulfurization with DSRP.

  2. 76 FR 14349 - Airworthiness Directives; British Aerospace Regional Aircraft Model HP.137 Jetstream Mk.1...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-16

    ... MLG leg pivot beam fastener bores for cracks. Do the inspections following British Aerospace Jetstream...) after replacement, eddy current inspect all the MLG leg pivot beam fastener bores for cracks. Do the... to exceed 27,000 flight cycles (landings), eddy current inspect all the MLG leg pivot beam...

  3. 75 FR 19209 - Airworthiness Directives; British Aerospace Regional Aircraft Model HP.137 Jetstream Mk.1...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-14

    ... Register approved the incorporation by reference of BAE Systems British Aerospace Jetstream Series 3100... issued AD 003-11- 2002 (which references BAE Systems Service Bulletin (SB) 32- JA020741), requiring an... unserviceable. In response to this development, BAE Systems issued SB 32- JA030644 so that a revised...

  4. 75 FR 3418 - Airworthiness Directives; British Aerospace Regional Aircraft Model HP.137 Jetstream Mk.1...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-21

    ... address this unsafe condition, the UK CAA issued AD 003-11- 2002 (which references BAE Systems Service... optimistic assessment of the component's safe life. The CAA UK issued AD G-2004-0029, superseding AD 003-11... JM5414. For the reasons described above, this new AD retains the requirements of UK CAA AD...

  5. Writing time estimation of EB mask writer EBM-9000 for hp16nm/logic11nm node generation

    NASA Astrophysics Data System (ADS)

    Kamikubo, Takashi; Takekoshi, Hidekazu; Ogasawara, Munehiro; Yamada, Hirokazu; Hattori, Kiyoshi

    2014-10-01

    The scaling of semiconductor devices is slowing down because of the difficulty in establishing their functionality at the nano-size level and also because of the limitations in fabrications, mainly the delay of EUV lithography. While multigate devices (FinFET) are currently the main driver for scalability, other types of devices, such as 3D devices, are being realized to relax the scaling of the node. In lithography, double or multiple patterning using ArF immersion scanners is still a realistic solution offered for the hp16nm node fabrication. Other lithography candidates are those called NGL (Next Generation Lithography), such as DSA (Directed-Self-Assembling) or nanoimprint. In such situations, shot count for mask making by electron beam writers will not increase. Except for some layers, it is not increasing as previously predicted. On the other hand, there is another aspect that increases writing time. The exposure dose for mask writing is getting higher to meet tighter specifications of CD uniformity, in other words, reduce LER. To satisfy these requirements, a new electron beam mask writer, EBM-9000, has been developed for hp16nm/logic11nm generation. Electron optical system, which has the immersion lens system, was evolved from EBM-8000 to achieve higher current density of 800A/cm2. In this paper, recent shot count and dose trend are discussed. Also, writing time is estimated for the requirements in EBM-9000.

  6. Flue gas desulfurization: the state of the art.

    PubMed

    Srivastava, R K; Jozewicz, W

    2001-12-01

    Coal-fired electricity-generating plants may use SO2 scrubbers to meet the requirements of Phase II of the Acid Rain SO2 Reduction Program. Additionally, the use of scrubbers can result in reduction of Hg and other emissions from combustion sources. It is timely, therefore, to examine the current status of SO2 scrubbing technologies. This paper presents a comprehensive review of the state of the art in flue gas desulfurization (FGD) technologies for coal-fired boilers. Data on worldwide FGD applications reveal that wet FGD technologies, and specifically wet limestone FGD, have been predominantly selected over other FGD technologies. However, lime spray drying (LSD) is being used at the majority of the plants employing dry FGD technologies. Additional review of the U.S. FGD technology applications that began operation in 1991 through 1995 reveals that FGD processes of choice recently in the United States have been wet limestone FGD, magnesium-enhanced lime (MEL), and LSD. Further, of the wet limestone processes, limestone forced oxidation (LSFO) has been used most often in recent applications. The SO2 removal performance of scrubbers has been reviewed. Data reflect that most wet limestone and LSD installations appear to be capable of approximately 90% SO2 removal. Advanced, state-of-the-art wet scrubbers can provide SO2 removal in excess of 95%. Costs associated with state-of-the-art applications of LSFO, MEL, and LSD technologies have been analyzed with appropriate cost models. Analyses indicate that the capital cost of an LSD system is lower than those of same capacity LSFO and MEL systems, reflective of the relatively less complex hardware used in LSD. Analyses also reflect that, based on total annualized cost and SO2 removal requirements: (1) plants up to approximately 250 MWe in size and firing low- to medium-sulfur coals (i.e., coals with a sulfur content of 2% or lower) may use LSD; and (2) plants larger than 250 MWe and firing medium- to high-sulfur coals (i

  7. Flue Gas Desulfurization: The State of the Art.

    PubMed

    Srivastava, R K; Jozewicz, W

    2001-12-01

    Coal-fired electricity-generating plants may use SO2 scrubbers to meet the requirements of Phase II of the Acid Rain SO2 Reduction Program. Additionally, the use of scrubbers can result in reduction of Hg and other emissions from combustion sources. It is timely, therefore, to examine the current status of SO2 scrubbing technologies. This paper presents a comprehensive review of the state of the art in flue gas desulfurization (FGD) technologies for coal-fired boilers. Data on worldwide FGD applications reveal that wet FGD technologies, and specifically wet limestone FGD, have been predominantly selected over other FGD technologies. However, lime spray drying (LSD) is being used at the majority of the plants employing dry FGD technologies. Additional review of the U.S. FGD technology applications that began operation in 1991 through 1995 reveals that FGD processes of choice recently in the United States have been wet limestone FGD, magnesium-enhanced lime (MEL), and LSD. Further, of the wet limestone processes, limestone forced oxidation (LSFO) has been used most often in recent applications. The SO2 removal performance of scrubbers has been reviewed. Data reflect that most wet limestone and LSD installations appear to be capable of ~90% SO2 removal. Advanced, state-of-the-art wet scrubbers can provide SO2 removal in excess of 95%. Costs associated with state-of-the-art applications of LSFO, MEL, and LSD technologies have been analyzed with appropriate cost models. Analyses indicate that the capital cost of an LSD system is lower than those of same capacity LSFO and MEL systems, reflective of the relatively less complex hardware used in LSD. Analyses also reflect that, based on total annualized cost and SO2 removal requirements: (1) plants up to ~250 MWe in size and firing low- to medium-sulfur coals (i.e., coals with a sulfur content of 2% or lower) may use LSD; and (2) plants larger than 250 MWe and firing medium- to high-sulfur coals (i.e., coals with a sulfur

  8. Results of testing various natural gas desulfurization adsorbents

    NASA Astrophysics Data System (ADS)

    Israelson, Gordon

    2004-06-01

    This article presents the results of testing many commercially available and some experimental sulfur adsorbents. The desired result of our testing was to find an effective method to reduce the quantity of sulfur in natural gas to less than 100 ppb volume (0.1 ppm volume). An amount of 100 ppb sulfur is the maximum limit permitted for Siemens Westinghouse solid oxide fuel cells (SOFCs). The tested adsorbents include some that rely only on physical adsorption such as activated carbon, some that rely on chemisorption such as heated zinc oxide, and some that may use both processes. The testing was performed on an engineering scale with beds larger than those used for typical laboratory tests. All tests were done at about 3.45 barg (50 psig). The natural gas used for testing was from the local pipeline in Pittsburgh and averaged 6 ppm volume total sulfur. The primary sulfur species were dimethyl sulfide (DMS), isopropyl mercaptan, tertiary butyl mercaptan, and tetrahydrothiophene. Some tests required several months to achieve a sulfur breakthrough of the bed. It was found that DMS always came through a desulfurizer bed first, independent of adsorption process. Since the breakthrough of DMS always exceeds the 100 ppb SOFC sulfur limit before other sulfurs were detected, an index was created to rate the adsorbents in units of ppm DMS × absorbent bed volume. This index is useful for calculating the expected adsorbent bed lifetime before sulfur breakthrough when the inlet natural gas DMS content is known. The adsorbents that are included in these reports were obtained from suppliers in the United States, the Netherlands, Japan, and England. Three activated carbons from different suppliers were found to have identical performance in removing DMS. One of these activated carbons was operated at four different space velocities and again showed the same performance. When using activated carbon as the basis of comparison for other adsorbents, three high-performance adsorbents

  9. Characterization of promising resist platforms for sub-30-nm HP manufacturability and EUV CAR extendibility study

    NASA Astrophysics Data System (ADS)

    Koh, Chawon; Georger, Jacque; Ren, Liping; Huang, George; Goodwin, Frank; Wurm, Stefan; Ashworth, Dominic; Montgomery, Warren; Pierson, Bill; Park, Joo-on; Naulleau, Patrick

    2010-04-01

    Extreme ultraviolet lithography (EUVL) is the most effective way to print sub-30 nm features. We characterized EUVL readiness of the three major resist platforms for sub-30 nm half-pitch (HP) manufacturability using a full-field ASML alpha demo tool (ADT) scanner and studied the extendibility of EUV chemically amplified resist (CAR). Based on an "M-factor" analysis, which shows the maturity of EUV resist for 28 nm HP manufacturability, a polymer-bound photoacid generator (PAG) resist was 78% ready, a PHS hybrid resist was 81%, and a molecular glass EUV resist was 58%. The polymer-bound resist showed good resolution for 25 nm HP using the ASML ADT. It also demonstrated fair linewidth roughness (LWR) and a good lithographic process margin of 18% exposure latitude (EL) and 160 nm depth of field (DOF) for 28 nm HP patterning compared with the other resist platforms, but its resist collapse and etch resistance need to be improved for manufacturability. PHS hybrid resist showed a fair etch resistance and resist collapse performance compared to the other resist platforms, but LWR needs to be improved. The molecular resist needs to mature further, especially in resist collapse and iso-dense (ID) bias. When considering its many strong points and control of lower acid diffusion, the polymer-bound PAG resist appears to be the most suitable platform for manufacturability and EUV CAR extension. We therefore would like to encourage the development of next generation polymer-bound PAG resist with a higher etch resistance. A process window of 80 nm DOF was demonstrated for 26 nm HP patterning and a measurable DOF for 25 nm HP was achieved with the polymer-bound PAG resist. Resist collapse and LWR are major issues for 22 nm HP patterning in manufacturing. LWR improvements were achieved with various techniques, and resist collapse was greatly improved with a novel approach that uses a residual resist layer. 16 nm HP line/space (L/S) image modulation and 18 nm HP resolution were

  10. Superoxide radical and UV irradiation in ultrasound assisted oxidative desulfurization (UAOD): A potential alternative for greener fuels

    NASA Astrophysics Data System (ADS)

    Chan, Ngo Yeung

    This study is aimed at improving the current ultrasound assisted oxidative desulfurization (UAOD) process by utilizing superoxide radical as oxidant. Research was also conducted to investigate the feasibility of ultraviolet (UV) irradiation-assisted desulfurization. These modifications can enhance the process with the following achievements: (1) Meet the upcoming sulfur standards on various fuels including diesel fuel oils and residual oils; (2) More efficient oxidant with significantly lower consumption in accordance with stoichiometry; (3) Energy saving by 90%; (4) Greater selectivity in petroleum composition. Currently, the UAOD process and subsequent modifications developed in University of Southern California by Professor Yen's research group have demonstrated high desulfurization efficiencies towards various fuels with the application of 30% wt. hydrogen peroxide as oxidant. The UAOD process has demonstrated more than 50% desulfurization of refractory organic sulfur compounds with the use of Venturella type catalysts. Application of quaternary ammonium fluoride as phase transfer catalyst has significantly improved the desulfurization efficiency to 95%. Recent modifications incorporating ionic liquids have shown that the modified UAOD process can produce ultra-low sulfur, or near-zero sulfur diesels under mild conditions with 70°C and atmospheric pressure. Nevertheless, the UAOD process is considered not to be particularly efficient with respect to oxidant and energy consumption. Batch studies have demonstrated that the UAOD process requires 100 fold more oxidant than the stoichiometic requirement to achieve high desulfurization yield. The expected high costs of purchasing, shipping and storage of the oxidant would reduce the practicability of the process. The excess use of oxidant is not economically desirable, and it also causes environmental and safety issues. Post treatments would be necessary to stabilize the unspent oxidant residual to prevent the waste

  11. Pressurized fluidized-bed hydroretorting of Eastern oil shales -- Sulfur control. Topical report for Subtask 3.1, In-bed sulfur capture tests; Subtask 3.2, Electrostatic desulfurization; Subtask 3.3, Microbial desulfurization and denitrification

    SciTech Connect

    Roberts, M.J.; Abbasian, J.; Akin, C.; Lau, F.S.; Maka, A.; Mensinger, M.C.; Punwani, D.V.; Rue, D.M.; Gidaspow, D.; Gupta, R.; Wasan, D.T.; Pfister, R.M.: Krieger, E.J.

    1992-05-01

    This topical report on ``Sulfur Control`` presents the results of work conducted by the Institute of Gas Technology (IGT), the Illinois Institute of Technology (IIT), and the Ohio State University (OSU) to develop three novel approaches for desulfurization that have shown good potential with coal and could be cost-effective for oil shales. These are (1) In-Bed Sulfur Capture using different sorbents (IGT), (2) Electrostatic Desulfurization (IIT), and (3) Microbial Desulfurization and Denitrification (OSU and IGT). The objective of the task on In-Bed Sulfur Capture was to determine the effectiveness of different sorbents (that is, limestone, calcined limestone, dolomite, and siderite) for capturing sulfur (as H{sub 2}S) in the reactor during hydroretorting. The objective of the task on Electrostatic Desulfurization was to determine the operating conditions necessary to achieve a high degree of sulfur removal and kerogen recovery in IIT`s electrostatic separator. The objectives of the task on Microbial Desulfurization and Denitrification were to (1) isolate microbial cultures and evaluate their ability to desulfurize and denitrify shale, (2) conduct laboratory-scale batch and continuous tests to improve and enhance microbial removal of these components, and (3) determine the effects of processing parameters, such as shale slurry concentration, solids settling characteristics, agitation rate, and pH on the process.

  12. Neurocysticercosis: HP10 Antigen Detection Is Useful for the Follow-up of the Severe Patients

    PubMed Central

    Fleury, Agnès; Garcia, Esperanza; Hernández, Marisela; Carrillo, Roger; Govezensky, Tzipe; Fragoso, Gladis; Sciutto, Edda; Harrison, Leslie J. S.; Parkhouse, R. Michael Evans

    2013-01-01

    Background The most severe clinical form of neurocysticercosis (NC) occurs when cysticerci are located in the subarachnoid space at the base of the brain (SaB). The diagnosis, monitoring and treatment of NC-SaB, constitutes a severe clinical challenge. Herein we evaluate the potential of the HP10 antigen detection enzyme-linked immunosorbent assay (HP10 Ag-ELISA) in the long term follow-up of NC-SaB cases. Assay performance was compared with that of Magnetic Resonance Imaging (MRI). In addition, the robustness of the HP10 Ag-ELISA was evaluated independently at two different institutions. Methodology/Principal Findings A double-blind prospective cohort trial was conducted involving 38 NC-SaB cases and a total of 108 paired serum and cerebrospinal fluid (CSF) samples taken at intervals of 4 to 8 months for up to 43 months. At each medical visit, results of sera and CSF HP10 Ag-ELISA and MRI obtained at last visit were compared and their accuracy was evaluated retrospectively, considering radiological evolution between appointments. In the long-term follow-up study, HP10 Ag-ELISA had a better agreement than MRI with retrospective radiological evaluation. High reproducibility of HP10 Ag-ELISA between laboratories was also demonstrated. Conclusions Results reported in this study establish for the first time the usefulness of the comparatively low cost HP10 Ag-ELISA for long term follow-up of NC-SaB patients. PMID:23505587

  13. Phosphorylation-Dependent Targeting of Tetrahymena HP1 to Condensed Chromatin

    PubMed Central

    Yale, Katerina; Tackett, Alan J.; Neuman, Monica; Bulley, Emily; Chait, Brian T.

    2016-01-01

    ABSTRACT The evolutionarily conserved proteins related to heterochromatin protein 1 (HP1), originally described in Drosophila, are well known for their roles in heterochromatin assembly and gene silencing. Targeting of HP1 proteins to specific chromatin locales is mediated, at least in part, by the HP1 chromodomain, which binds to histone H3 methylated at lysine 9 that marks condensed regions of the genome. Mechanisms that regulate HP1 targeting are emerging from studies with yeast and metazoans and point to roles for posttranslational modifications. Here, we report that modifications of an HP1 homolog (Hhp1) in the ciliate model Tetrahymena thermophila correlated with the physiological state and with nuclear differentiation events involving the restructuring of chromatin. Results support the model in which Hhp1 chromodomain binds lysine 27-methylated histone H3, and we show that colocalization with this histone mark depends on phosphorylation at a single Cdc2/Cdk1 kinase site in the “hinge region” adjacent to the chromodomain. These findings help elucidate important functional roles of reversible posttranslational modifications of proteins in the HP1 family, in this case, regulating the targeting of a ciliate HP1 to chromatin regions marked with methylated H3 lysine 27. IMPORTANCE Compacting the genome to various degrees influences processes that use DNA as a template, such as gene transcription and replication. This project was aimed at learning more about the cellular mechanisms that control genome compaction. Posttranslational modifications of proteins involved in genome condensation are emerging as potentially important points of regulation. To help elucidate protein modifications and how they affect the function of condensation proteins, we investigated the phosphorylation of the chromatin protein called Hhp1 in the ciliated protozoan Tetrahymena thermophila. This is one of the first functional investigations of these modifications of a nonhistone

  14. Phosphorylation-Dependent Targeting of Tetrahymena HP1 to Condensed Chromatin.

    PubMed

    Yale, Katerina; Tackett, Alan J; Neuman, Monica; Bulley, Emily; Chait, Brian T; Wiley, Emily

    2016-01-01

    The evolutionarily conserved proteins related to heterochromatin protein 1 (HP1), originally described in Drosophila, are well known for their roles in heterochromatin assembly and gene silencing. Targeting of HP1 proteins to specific chromatin locales is mediated, at least in part, by the HP1 chromodomain, which binds to histone H3 methylated at lysine 9 that marks condensed regions of the genome. Mechanisms that regulate HP1 targeting are emerging from studies with yeast and metazoans and point to roles for posttranslational modifications. Here, we report that modifications of an HP1 homolog (Hhp1) in the ciliate model Tetrahymena thermophila correlated with the physiological state and with nuclear differentiation events involving the restructuring of chromatin. Results support the model in which Hhp1 chromodomain binds lysine 27-methylated histone H3, and we show that colocalization with this histone mark depends on phosphorylation at a single Cdc2/Cdk1 kinase site in the "hinge region" adjacent to the chromodomain. These findings help elucidate important functional roles of reversible posttranslational modifications of proteins in the HP1 family, in this case, regulating the targeting of a ciliate HP1 to chromatin regions marked with methylated H3 lysine 27. IMPORTANCE Compacting the genome to various degrees influences processes that use DNA as a template, such as gene transcription and replication. This project was aimed at learning more about the cellular mechanisms that control genome compaction. Posttranslational modifications of proteins involved in genome condensation are emerging as potentially important points of regulation. To help elucidate protein modifications and how they affect the function of condensation proteins, we investigated the phosphorylation of the chromatin protein called Hhp1 in the ciliated protozoan Tetrahymena thermophila. This is one of the first functional investigations of these modifications of a nonhistone chromatin

  15. Linking deep earth to surface processes in the Woodlark Rift of Papua New Guinea; a framework for understanding (U)HP exhumation globally

    NASA Astrophysics Data System (ADS)

    Baldwin, S.; Fitzgerald, P. G.; Bermudez, M. A.; Webb, L. E.; Moucha, R.; Miller, S. R.; Catalano, J. P.; Zirakparvar, N. A.

    2012-12-01

    During the Cenozoic the leading edge of the AUS plate was subducted northwards beneath the forearc of oceanic island arc(s), during its north-northeast passage over a complexly structured mantle. Sediments and basalts were metamorphosed under (U)HP conditions to form blueschists and eclogites, and lower-grade metamorphic rocks that are now exposed throughout New Guinea, primarily south of, and structurally beneath, obducted ophiolites. In the Woodlark Rift the youngest (2-8 Ma) (U)HP rocks on Earth were exhumed from mantle depths (>90 km) at plate tectonic rates (1-4 cm yr-1) west of the active Woodlark Basin seafloor spreading center rift tip. How these (U)HP rocks were exhumed is the focus of an ongoing collaborative multidisciplinary project which aims to understand linkages between deep earth, plate tectonic, and surface processes in the Woodlark Rift. Since the Late Miocene, a regionally extensive subduction complex was exhumed on the southern-rifted margin of the Woodlark Basin (Pocklington Rise), and in the lower plates of the D'Entrecasteaux, Misima, and Dayman dome metamorphic core complexes. Late Miocene-to-Pliocene metamorphism of sediments and basalts preceded diachronous exhumation from east to west, in the same direction as rift propagation. In contrast the northern-rifted margin (Woodlark Rise) comprises mid-Miocene to Pliocene volcanic flows and pyroclastic material ranging in composition from basalt to rhyolite, with capping limestone. The age of volcanic rocks on the northern-rifted margin also youngs from east to west. Pliocene to active syn-rift volcanism on the Woodlark Rise and in the D'Entrecasteaux Islands is synchronous with (U)HP exhumation, and results from decompression melting of a relict mantle wedge. As lithospheric extension proceeds, volcanic compositions evolve from subduction zone geochemical signatures (i.e., negative HFSE anomalies) toward E-MORB. Preliminary mantle convection models investigate large-scale background mantle

  16. Heterochromatin protein 1 (HP1) connects the FACT histone chaperone complex to the phosphorylated CTD of RNA polymerase II

    PubMed Central

    Kwon, So Hee; Florens, Laurence; Swanson, Selene K.; Washburn, Michael P.; Abmayr, Susan M.; Workman, Jerry L.

    2010-01-01

    Heterochromatin protein 1 (HP1) is well known as a silencing protein found at pericentric heterochromatin. Most eukaryotes have at least three isoforms of HP1 that play differential roles in heterochromatin and euchromatin. In addition to its role in heterochromatin, HP1 proteins have been shown to function in transcription elongation. To gain insights into the transcription functions of HP1, we sought to identify novel HP1-interacting proteins. Biochemical and proteomic approaches revealed that HP1 interacts with the histone chaperone complex FACT (facilitates chromatin transcription). HP1c interacts with the SSRP1 (structure-specific recognition protein 1) subunit and the intact FACT complex. Moreover, HP1c guides the recruitment of FACT to active genes and links FACT to active forms of RNA polymerase II. The absence of HP1c partially impairs the recruitment of FACT into heat-shock loci and causes a defect in heat-shock gene expression. Thus, HP1c functions to recruit the FACT complex to RNA polymerase II. PMID:20889714

  17. An integrated biodesulfurization process, including inoculum preparation, desulfurization and sulfate removal in a single step, for removing sulfur from oils.

    SciTech Connect

    Tangaromsuk, Jantana; Borole, Abhijeet P; Kruatrachue, Maleeya; Pokethitiyook, Prayad

    2008-01-01

    BACKGROUND: A single-stage reactor, in which the growth of bacterial culture, induction of desulfurizing enzymes, and desulfurization reaction are carried out in a single step, was adopted to investigate desulfurization of DBT at high cell densities. IGTS8 was used as the biocatalyst. Optimal condition for the bacterial growth and DBT desulfurization were also investigated. RESULTS: Optimization of fermentation conditions was necessary to obtain high cell densities including controlling accumulation of acetate. Under optimal operating conditions, the maximum OD600 was measured to be 26.6 at 118 h of cultivation. When biodesulfurization of DBT in model oil with a high cell density culture of IGTS8 was investigated, accumulation of sulfate was found to limit the extent of desulfurization. A sulfate removal step was added to obtain a single-stage integrated biodesulfurization process. Sulfate removal was achieved via an aqueous bleed stream and use of a separation unit to recycle the organic phase. CONCLUSION : A proof of principle of a complete system capable of biocatalyst growth, induction, desulfurization and by-product separation was demonstrated. This system enables simplification of the biodesulfurization process and has potential to lower the operating cost of the bioprocess.

  18. Desulfurization of coal. Final report. [Flotation followed by olefin and vinyl monomer treatment

    SciTech Connect

    Dichter, M.; Sanduja, M.

    1980-10-01

    Ohio coal, like many other types of coal, has a high sulfur as well as ash content. We at PRCA, through a series of steps involving the treatment of coal with an olefin-catalyst and/or catalyzed oxidizing system, have established the following: (1) Crushing and pulverizing of coal to a size of 150 to 200 mesh is an important factor in the process of desulfurization, as this allows improvement of the efficiency of flotation and chemical desulfurization. (2) Flotation results in a significant reduction of sulfur and ash content of the coal and reduces the amount of water absorbed on the pulverized coal when petroleum fractions are introduced into the flotation process. Coal containing 4.3% and 2.7% sulfur have been desulfurized to 2.8% to 3.0% and 1.5% to 1.9%, respectively. The ash content has been reduced after flotation from 10.7% to 6.5% of the Pittsburgh No. 8 coal and from 16.5% to 10.5% of a coal provided by Consolidation Coal Co. (3) Chemical treatment with olefins and monomers allows complete removal of the rest of the pyritic sulfur and part of the organic sulfur. The higher molecular weight olefins give better results and an introduction of some maleic anhydride monomer helps to get a higher reduction of the sulfur in the coal. The presence of an alkaline medium (NaOH or Na/sub 2/CO/sub 3/) enhances the sulfur removal efficiency. (4) Elevated temperatures and pressures allows reduction of the time of reaction to obtain lower sulfur content coal. However, the pressure in the range of 100 to 200 psi allows achievement of an optimum desulfurization of treated coal. Even 25 to 30 psi has shown satisfactory results in the same time. (5) The results of desulfurization by a monomer (olefin) treatment are given. Further work on the desulfurization of the Ohio coals is recommended in a small scale pilot plant on a continuous basis. This pilot plant will represent an approximation of a real plant which will allow the necessary insight needed for scale up.

  19. [Effects of intergenic interaction of the high pigmentation gene hp-2(dg) (high pigment-2 dark green) with the gene B (beta-carotene) in tomato].

    PubMed

    Kuzemenskiĭ, A V

    2008-01-01

    It was shown that during intergenic interaction of genes hp-2(dg) and B in dihomozygote an additive factor is formed activating biogenesis of beta-carotene in tomato fruits. In the genotype B/B//hp-2(dg)/hp-2(dg) there is preserved the positive effects of the gene hp-2(dg) on the content of ascorbic acid and the negative one on the content of titrated acids. With this stabilization of the gene hp-2(dg) genetic depression is observed, which is manifested in the increased productivity of B/B//hp-2(dg)/hp-2(dg)-genotypes.

  20. HP1 Binding to Chromatin Methylated at H3K9 Is Enhanced by Auxiliary Factors▿

    PubMed Central

    Eskeland, Ragnhild; Eberharter, Anton; Imhof, Axel

    2007-01-01

    A large portion of the eukaryotic genome is packaged into transcriptionally silent heterochromatin. Several factors that play important roles during the establishment and maintenance of this condensed form have been identified. Methylation of lysine 9 within histone H3 and the subsequent binding of the chromodomain protein heterochromatin protein 1 (HP1) are thought to initiate heterochromatin formation in vivo and to propagate a heterochromatic state lasting through several cell divisions. For the present study we analyzed the binding of HP1 to methylated chromatin in a fully reconstituted system. In contrast to its strong binding to methylated peptides, HP1 binds only weakly to methylated chromatin. However, the addition of recombinant SU(VAR) protein, such as ACF1 or SU(VAR)3-9, facilitates HP1 binding to chromatin methylated at lysine 9 within the H3 N terminus (H3K9). We propose that HP1 has multiple target sites that contribute to its recognition of chromatin, only one of them being methylated at H3K9. These findings have implications for the mechanisms of recognition of specific chromatin modifications in vivo. PMID:17101786

  1. Complete genome sequence of Marinobacter adhaerens type strain (HP15), a diatom-interacting marine microorganism.

    PubMed

    Gärdes, Astrid; Kaeppel, Eva; Shehzad, Aamir; Seebah, Shalin; Teeling, Hanno; Yarza, Pablo; Glöckner, Frank Oliver; Grossart, Hans-Peter; Ullrich, Matthias S

    2010-09-28

    Marinobacter adhaerens HP15 is the type strain of a newly identified marine species, which is phylogenetically related to M. flavimaris, M. algicola, and M. aquaeolei. It is of special interest for research on marine aggregate formation because it showed specific attachment to diatom cells. In vitro it led to exopolymer formation and aggregation of these algal cells to form marine snow particles. M. adhaerens HP15 is a free-living, motile, rod-shaped, Gram-negative gammaproteobacterium, which was originally isolated from marine particles sampled in the German Wadden Sea. M. adhaerens HP15 grows heterotrophically on various media, is easy to access genetically, and serves as a model organism to investigate the cellular and molecular interactions with the diatom Thalassiosira weissflogii. Here we describe the complete and annotated genome sequence of M. adhaerens HP15 as well as some details on flagella-associated genes. M. adhaerens HP15 possesses three replicons; the chromosome comprises 4,422,725 bp and codes for 4,180 protein-coding genes, 51 tRNAs and three rRNA operons, while the two circular plasmids are ~187 kb and ~42 kb in size and contain 178 and 52 protein-coding genes, respectively.

  2. Early Cretaceous extensional reworking of the Triassic HP-UHP metamorphic orogen in Eastern China

    NASA Astrophysics Data System (ADS)

    Lin, W.; Ji, W.; Faure, M.; Wu, L.; Li, Q. L.; Shi, Y.; Scharer, U.; Wang, F.; Wang, Q.

    2015-12-01

    Corresponding to the Early Mesozoic continental subduction between the North China Block (NCB) and the South China Block (SCB), the Tongbaishan-Hong'an-Dabieshan-Sulu massifs are famous for their HP-UHP metamorphism. More than 50% of the HP-UHP Orogenic Belt was significantly reworked by Early Cretaceous extensional tectonics. This Early Cretaceous event with a fast cooling period, at 130-120 Ma, superimposed on the Early Mesozoic HP-UHP orogenic belt and intensively changed the architecture of this orogen. Each individual segment documents different Early Cretaceous extensional structures, namely the central Tongbaishan domain is a metamorphic core complex (MCC) represented by an A-type non-cylindrical antiform; the central Dabieshan domain is a typical Cordilleran-type migmatite-cored MCC; the Southern Sulu UHP domain is a "wedge-shaped" structure exhumed by a simple detachment fault. These late stage extensional structures expose the previous HP-UHP orogenic belt as fragments along the NCB-SCB boundary. The geodynamic setting of this Early Cretaceous extensional tectonics along the HP-UHP orogen is a part of a 1000 km-scale crustal extension belt that is widespread in eastern Eurasia continent from Trans-Baikal to the central part of the South China Block. Convective erosion or delamination of the mantle lithosphere might be considered as a possible mechanism for mantle removal.

  3. Early Cretaceous extensional reworking of the Triassic HP-UHP metamorphic orogen in Eastern China

    NASA Astrophysics Data System (ADS)

    Lin, Wei; Ji, Wenbin; Faure, Michel; Wu, Lin; Li, Qiuli; Shi, Yonghong; Scharer, Urs; Wang, Fei; Wang, Qingchen

    2015-11-01

    Corresponding to the Early Mesozoic continental subduction between the North China Block (NCB) and the South China Block (SCB), the Tongbaishan-Hong'an-Dabieshan-Sulu massifs are famous for their HP-UHP metamorphism. More than 50% of the HP-UHP Orogenic Belt was significantly reworked by Early Cretaceous extensional tectonics. This Early Cretaceous event with a fast cooling period, at 130-120 Ma, superimposed on the Early Mesozoic HP-UHP orogenic belt and intensively changed the architecture of this orogen. Each individual segment documents different Early Cretaceous extensional structures, namely the central Tongbaishan domain is a metamorphic core complex (MCC) represented by an A-type non-cylindrical antiform; the central Dabieshan domain is a typical Cordilleran-type migmatite-cored MCC; the Southern Sulu UHP domain is a "wedge-shaped" structure exhumed by a simple detachment fault. These late stage extensional structures expose the previous HP-UHP orogenic belt as fragments along the NCB-SCB boundary. The geodynamic setting of this Early Cretaceous extensional tectonics along the HP-UHP orogen is a part of a 1000 km-scale crustal extension belt that is widespread in eastern Eurasia continent from Trans-Baikal to the central part of SCB. Convective erosion or delamination of the mantle lithosphere might be considered as a possible mechanism for mantle removal.

  4. Up-regulation of HP1γ expression during neuronal maturation promotes axonal and dendritic development in mouse embryonic neocortex.

    PubMed

    Oshiro, Hiroaki; Hirabayashi, Yusuke; Furuta, Yasuhide; Okabe, Shigeo; Gotoh, Yukiko

    2015-02-01

    Immature neurons undergo morphological and physiological changes including axonal and dendritic development to establish neuronal networks. As the transcriptional status changes at a large number of genes during neuronal maturation, global changes in chromatin modifiers may take place in this process. We now show that the amount of heterochromatin protein 1γ (HP1γ) increases during neuronal maturation in the mouse neocortex. Knockdown of HP1γ suppressed axonal and dendritic development in mouse embryonic neocortical neurons in culture, and either knockdown or knockout of HP1γ impaired the projection of callosal axons of superficial layer neurons to the contralateral hemisphere in the developing neocortex. Conversely, forced expression of HP1γ facilitated axonal and dendritic development, suggesting that the increase of HP1γ is a rate limiting step in neuronal maturation. These results together show an important role for HP1γ in promoting axonal and dendritic development in maturing neurons.

  5. Ada Compiler Validation Summary Report. Certificate Number: 891019W1. 10178, Hewlett Packard Company HP 9000 Series 800 Ada Compiler, Version 4.35 HP 9000 Series 800 Model 850. Completion of On-Site Testing: 19 October 1989

    DTIC Science & Technology

    1989-10-19

    ACVC Version: 1.10 Certificate Number: 891019W1.10178 Host Computer: Machine : HP 9000 Series 800 Model 850 Operating System: HP-UX Version A.B3.10...release 3.1) Memory Size: 96 Mb Target Computer: Machine : HP 9000 Series 800 Model 850 Operating System: HP-UX Version A.B3.10 (release 3.1) Memory...allowed implementation dependencies correspond to implementation-dependent pragmas, to certain machine -dependent conventions as mentioned in Chapter 13

  6. Prediction of Extracellular Proteases of the Human Pathogen Helicobacter pylori Reveals Proteolytic Activity of the Hp1018/19 Protein HtrA

    PubMed Central

    Löwer, Martin; Weydig, Christiane; Metzler, Dirk; Reuter, Andreas; Starzinski-Powitz, Anna

    2008-01-01

    Exported proteases of Helicobacter pylori (H. pylori) are potentially involved in pathogen-associated disorders leading to gastric inflammation and neoplasia. By comprehensive sequence screening of the H. pylori proteome for predicted secreted proteases, we retrieved several candidate genes. We detected caseinolytic activities of several such proteases, which are released independently from the H. pylori type IV secretion system encoded by the cag pathogenicity island (cagPAI). Among these, we found the predicted serine protease HtrA (Hp1019), which was previously identified in the bacterial secretome of H. pylori. Importantly, we further found that the H. pylori genes hp1018 and hp1019 represent a single gene likely coding for an exported protein. Here, we directly verified proteolytic activity of HtrA in vitro and identified the HtrA protease in zymograms by mass spectrometry. Overexpressed and purified HtrA exhibited pronounced proteolytic activity, which is inactivated after mutation of Ser205 to alanine in the predicted active center of HtrA. These data demonstrate that H. pylori secretes HtrA as an active protease, which might represent a novel candidate target for therapeutic intervention strategies. PMID:18946507

  7. Prediction of extracellular proteases of the human pathogen Helicobacter pylori reveals proteolytic activity of the Hp1018/19 protein HtrA.

    PubMed

    Löwer, Martin; Weydig, Christiane; Metzler, Dirk; Reuter, Andreas; Starzinski-Powitz, Anna; Wessler, Silja; Schneider, Gisbert

    2008-01-01

    Exported proteases of Helicobacter pylori (H. pylori) are potentially involved in pathogen-associated disorders leading to gastric inflammation and neoplasia. By comprehensive sequence screening of the H. pylori proteome for predicted secreted proteases, we retrieved several candidate genes. We detected caseinolytic activities of several such proteases, which are released independently from the H. pylori type IV secretion system encoded by the cag pathogenicity island (cagPAI). Among these, we found the predicted serine protease HtrA (Hp1019), which was previously identified in the bacterial secretome of H. pylori. Importantly, we further found that the H. pylori genes hp1018 and hp1019 represent a single gene likely coding for an exported protein. Here, we directly verified proteolytic activity of HtrA in vitro and identified the HtrA protease in zymograms by mass spectrometry. Overexpressed and purified HtrA exhibited pronounced proteolytic activity, which is inactivated after mutation of Ser205 to alanine in the predicted active center of HtrA. These data demonstrate that H. pylori secretes HtrA as an active protease, which might represent a novel candidate target for therapeutic intervention strategies.

  8. Remaining activity determination of the resid desulfurization catalyst in a commerical plant

    SciTech Connect

    Yung-Ji Tarng; Sheng-Yang Ju

    1996-12-31

    The objective of this paper is to present a method to determine the remaining catalyst activity of the resid desulfurization plant. Using the daily available operating data, we can establish a performance curve which is a temperature versus days on stream curve. By the use of the performance curve, we can in situ predict how much the catalyst life remains. With the knowledge of the catalyst life remaining, plant engineers are able to control the operating conditions to meet the specified run length of the catalyst suggested by the catalyst venders and refinery planning department. There are five heavy oil desulfurization (RDS) plants in Chinese Petroleum Corporation (CPC) to produce the low sulfur fuel oil and low metal content feed stocks for the downstream processes. In general four or five reactors are connected in series for the reacting system and catalysts of various types are loaded in each reactor. 3 refs., 1 fig., 4 tabs.

  9. Reclamation of abandoned surface coal mined land using flue gas desulfurization products

    SciTech Connect

    Chen, L.; Kost, D.; Dick, W.A.

    2009-07-01

    Details are given of a field-scale research project where the Fleming site, in Ohio, of highly degraded and acid-forming abandoned surface coal-mined land, was reclaimed using a dry flue gas desulfurization product from an atmospheric fluidized bed combustion burner at a General Motors plant Pontiac, MI, which burned eastern Ohio coal and used dolomitic limestone for desulfurization. Plots were seeded with a mixture of grasses, wheat and clover, in 1994 and soil and water samples were analysed in 1995 and in 2009. It was found that FGD-treated plots promoted good regenerative growth, similar to that in plots using more concentrated re-soil material. The FGD treatment also greatly improved overall water quality. 3 figs., 4 tabs.

  10. Characterization and fixed-bed testing of a nickel-based hot gas desulfurization sorbent

    SciTech Connect

    Gasper-Galvin, L.D.; Swisher, J.H.; Hammerbeck, K.

    1994-10-01

    The objective of this project was to (1) extend a preliminary investigation completed earlier on dispersed nickel sorbents by developing new processing methods, characterizing sorbent materials more extensively, and evaluating the materials in fixed bed reactor tests, and (2) to determine the feasibility of using dispersed nickel sorbents with reductive regeneration for hot gas desulfurization. One of the properties of nickel that is somewhat unique is that it forms a liquid sulfide at sufficiently high temperatures with high sulfur potentials or H{sub 2}S levels. A eutectic exists in the Ni-S phase diagram at 637 C and a composition of 33.4 wt% or 21.5 wt% S. Under controlled conditions, the formation of a liquid phase can be used to advantage in hot gas desulfurization. Sorbent preparation, the experimental unit, and experimental procedure are described. Results from the sorbent, 24Ni-7Cu-Al{sub 2}O{sub 3}, are given.

  11. Fluence to Hp(3) conversion coefficients for neutrons from thermal to 15 MeV.

    PubMed

    Gualdrini, G; Ferrari, P; Tanner, R

    2013-12-01

    The recent statement on tissue reactions issued by the International Commission on Radiological Protection in April 2011 recommends a very significant reduction in the equivalent dose annual limit for the eye lens from 150 to 20 mSv y(-1); this has stimulated a lot of interest in eye lens dosimetry in the radiation protection community. Until now no conversion coefficients were available for the operational quantity Hp(3) for neutrons. The scope of the present work was to extend previous evaluations of H*(10) and Hp(10) performed at the PTB in 1995 to provide also Hp(3) data for neutrons. The present work is also intended to complete the studies carried out on photons during the last 4 y within the European Union-funded ORAMED (optimisation of radiation protection for medical staff) project.

  12. Ray-tracing polymorphic multidomain spectral/hp elements for isosurface rendering.

    PubMed

    Nelson, Blake; Kirby, Robert M

    2006-01-01

    The purpose of this paper is to present a ray-tracing isosurface rendering algorithm for spectral/hp (high-order finite) element methods in which the visualization error is both quantified and minimized. Determination of the ray-isosurface intersection is accomplished by classic polynomial root-finding applied to a polynomial approximation obtained by projecting the finite element solution over element-partitioned segments along the ray. Combining the smoothness properties of spectral/hp elements with classic orthogonal polynomial approximation theory, we devise an adaptive scheme which allows the polynomial approximation along a ray-segment to be arbitrarily close to the true solution. The resulting images converge toward a pixel-exact image at a rate far faster than sampling the spectral/hp element solution and applying classic low-order visualization techniques such as marching cubes.

  13. Enzymatic desulfurization of coal. Second quarterly report, October 1--December 15, 1988

    SciTech Connect

    Marquis, J.K.; Kitchell, J.P.

    1988-12-15

    Our current efforts to develop clean coal technology emphasize the advantages of enzymatic desulfurization techniques and have specifically addressed the potential of using partially-purified extracellular microbial enzymes or commercially available enzymes. Our work is focused on the treatment of ``model`` organic sulfur compounds such as dibenzothiophene (DBT) and ethylphenylsulfide (EPS). Furthermore, we are designing experiments to facilitate the enzymatic process by means of a hydrated organic solvent matrix.

  14. Pore structure and reactivity changes in hot coal gas desulfurization sorbents

    SciTech Connect

    Sotirchos, S.V.

    1991-05-01

    The primary objective of the project was the investigation of the pore structure and reactivity changes occurring in metal/metal oxide sorbents used for desulfurization of hot coal gas during sulfidation and regeneration, with particular emphasis placed on the effects of these changes on the sorptive capacity and efficiency of the sorbents. Commercially available zinc oxide sorbents were used as model solids in our experimental investigation of the sulfidation and regeneration processes.

  15. Preparation of sodium humate/{alpha}-aluminum oxide adsorbents for flue gas desulfurization

    SciTech Connect

    Sun, Z.G.; Gao, H.Y.; Hu, G.X.; Li, Y.H.

    2009-06-15

    A new composite adsorbent of sodium humate (HNa)=alpha-aluminium oxide ({alpha}-Al{sub 2}O{sub 3}) for flue gas desulfurization (FGD) was prepared using the impregnation method. Both the adsorbent of {alpha}-Al{sub 2}O{sub 3} and HNa={alpha}-Al{sub 2}O{sub 3} were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), energy dispersive X-ray spectrometer (EDS), and scanning electron microscope (SEM). Desulfurization activity of the adsorbent impregnated with ammonia (NH{sub 4}OH) was investigated in a fixed-bed quartz reactor. Experimental results indicate that HNa, which coats the {alpha}-Al{sub 2}O{sub 3} fibers impregnated with HNa solution, improved the property of {alpha}-Al{sub 2}O{sub 3} support for FGD. On the other hand, the HNa-coating on the adsorbent of HNa/{alpha}-Al{sub 2}O{sub 3} impregnated with NH{sub 4}OH played an important role in enhancing the desulfurization property of the {alpha}-Al{sub 2}O{sub 3}. Due to the strong adsorption capability of HNa, more NH{sub 4}OH was adsorbed in the adsorbent of HNa/{alpha}-Al{sub 2}O{sub 3} the longer a high sulfur dioxide (SO{sub 2}) conversation rate was maintained. In addition, because the desulfurization product was a compound fertilizer consisting of ammonium sulfate ((NH{sub 4}){sub 2}SO{sub 4}), ammonium humate (HNH{sub 4}), and HNa, the recycling use of {alpha}-Al{sub 2}O{sub 3} was also easily achieved. Thus, this study can provide a new cost-effective way to remove SO{sub 2} from flue gas.

  16. Sulfidation of a Novel Iron Sorbent Supported on Lignite Chars during Hot Coal Gas Desulfurization

    NASA Astrophysics Data System (ADS)

    Yin, Fengkui; Yu, Jianglong; Gupta, Sushil; Wang, Shaoyan; Wang, Dongmei; Yang, Li; Tahmasebi, Arash

    The sulfidation behavior of novel iron oxide sorbents supported using activated-chars during desulfurization of hot coal gases has been studied. The sulfidation of the char-supported sorbents was investigated using a fixed-bed quartz reactor in the temperature range of 673K to 873K. The product gases were analyzed using a GC equipped with a TCD and a FPD detector. The sorbent samples before and after sulfidation were examined using SEM and XRD.

  17. Physicochemical characterizations and desulfurization properties in coal combustion of three calcium and sodium industrial wastes

    SciTech Connect

    Jun Cheng; Junhu Zhou; Jianzhong Liu; Xinyu Cao; Kefa Cen

    2009-05-15

    To recycle industrial wastes and reduce SO{sub 2} pollutant emission in coal combustion, the mineralogical compositions, porosity structures, surface morphologies, and desulfurization properties of three calcium and sodium industrial wastes were investigated via X-ray diffraction (XRD), porosimeter, scanning electron microscopy (SEM), and a fixed-bed reactor. (1) White lime mud (WLM) mainly composed of CaCO{sub 3} with Na{sub 2}O and K{sub 2}O impurities has smaller CaCO{sub 3} particles and a higher surface area than limestone. But calcined WLM has larger CaO particles and a lower surface area than limestone calcined at 1200{sup o}C for 300 s. (2) Calcium carbide residue (CCR) mainly composed of Ca(OH)2, has the highest surface area and smaller Ca(OH){sub 2} particles than the CaCO{sub 3} particles in WLM. Its surface area monotonously and dramatically decreases at 1200{sup o}C for 300 s, but the sintered CaO particles are still smaller than those in the limestone. (3) When brine sludge (BS), mainly composed of NaCl and CaCO{sub 3}, is heated at 1200{sup o}C for 300 s, the NaCl/CaO eutectic solvent facilitates the aggregation of some complex composites to form many larger particles. (4) WLM gives the highest desulfurization efficiency of 80.4% at 1000{sup o}C and 65.0% at 1100{sup o}C in coal combustion. Combined CCR and limestone give a synergistic desulfurization efficiency of 45.8% at 1200{sup o}C. BS with a molar ratio of Na/Ca at 1:15 effectively promotes the synergistic desulfurization efficiency of combined CCR and limestone to a peak of 54.9% at 1200{sup o}C. 23 refs., 10 figs., 3 tabs.

  18. Thermal preparation effects on the x-ray diffractograms of compounds produced during flue gas desulfurization

    SciTech Connect

    Wertz, D.L.; Burns, K.H.; Keeton, R.W.

    1995-12-31

    The diffractograms of syn-gypsum and of flue gas desulfurization products indicate that CaSO{sub 4} {center_dot} 2H{sub 2}O is converted to other phase(s) when heated to 100{degrees}C. Syn-hannebachite CaSO{sub 3}{center_dot}0.5H{sub 2}O is unaffected by similar thermal treatment. 6 refs., 3 figs.

  19. Test and Characterization of Some Zeolite Supported Gas Phase Desulfurization Sorbents

    DTIC Science & Technology

    2009-06-01

    of-the-art SOFC electrode material is improving, the gas phase desulfurization step at high temperature is still essential to SOFCs . Our report ...NOTICES Disclaimers The findings in this report are not to be construed as an official Department of the Army position unless so...the use thereof. Destroy this report when it is no longer needed. Do not return it to the originator. Army Research Laboratory Adelphi, MD

  20. Biocatalytic desulfurization of thiophenic compounds and crude oil by newly isolated bacteria.

    PubMed

    Mohamed, Magdy El-Said; Al-Yacoub, Zakariya H; Vedakumar, John V

    2015-01-01

    Microorganisms possess enormous highly specific metabolic activities, which enable them to utilize and transform nearly every known chemical class present in crude oil. In this context, one of the most studied biocatalytic processes is the biodesulfurization (BDS) of thiophenic sulfur-containing compounds such as benzothiophene (BT) and dibenzothiophene (DBT) in crude oils and refinery streams. Three newly isolated bacterial strains, which were affiliated as Rhodococcus sp. strain SA11, Stenotrophomonas sp. strain SA21, and Rhodococcus sp. strain SA31, were enriched from oil contaminated soil in the presence of DBT as the sole S source. GC-FID analysis of DBT-grown cultures showed consumption of DBT, transient formation of DBT sulfone (DBTO2) and accumulation of 2-hydroxybiphenyl (2-HBP). Molecular detection of the plasmid-borne dsz operon, which codes for the DBT desulfurization activity, revealed the presence of dszA, dszB, and dszC genes. These results point to the operation of the known 4S pathway in the BDS of DBT. The maximum consumption rate of DBT was 11 μmol/g dry cell weight (DCW)/h and the maximum formation rate of 2-HBP formation was 4 μmol/g DCW/h. Inhibition of both cell growth and DBT consumption by 2-HBP was observed for all isolates but SA11 isolate was the least affected. The isolated biocatalysts desulfurized other model DBT alkylated homologs. SA11 isolate was capable of desulfurizing BT as well. Resting cells of SA11 exhibited 10% reduction in total sulfur present in heavy crude oil and 18% reduction in total sulfur present in the hexane-soluble fraction of the heavy crude oil. The capabilities of the isolated bacteria to survive and desulfurize a wide range of S compounds present in crude oil are desirable traits for the development of a robust BDS biocatalyst to upgrade crude oils and refinery streams.

  1. Enzymatic desulfurization of coal. Fourth quarterly report, March 16--June 15, 1989

    SciTech Connect

    Boyer, Y.N.; Crooker, S.C.; Kitchell, J.P.; Nochur, S.V.; Marquis, J.K.

    1989-06-16

    Our current efforts to develop clean coal technology emphasize the advantages of enzymatic desulfurization techniques and have specifically addressed the potential of using partially-purified extracellular microbial enzymes as well as commercially available enzymes. Our work is focused on the treatment of ``model`` organic sulfur compounds such as dibenzothiophene (DBT) and ethylphenylsulfide (EPS). Furthermore, we are designing experiments to facilitate the enzymatic process by means of a hydrated organic solvent matrix.

  2. Sulfur oxides control technology series: Flue-gas desulfurization. Dual alkali process. Summary report

    SciTech Connect

    Not Available

    1980-10-01

    The report describes a dual alkali (or double alkali) flue gas desulfurization (FGD), which is a throwaway process in which sulfur dioxide (SO2) is removed from the flue gas by a soluble sodium-based scrubbing liquor. The collected SO2 is precipitated as calcium sulfite (CaSO3), calcium sulfate (CaSO4), or a mixed crystal of both salts, and is purged from the system.

  3. HP1BP3 is a novel histone H1 related protein with essential roles in viability and growth

    PubMed Central

    Garfinkel, Benjamin P.; Melamed-Book, Naomi; Anuka, Eli; Bustin, Michael; Orly, Joseph

    2015-01-01

    The dynamic architecture of chromatin is vital for proper cellular function, and is maintained by the concerted action of numerous nuclear proteins, including that of the linker histone H1 variants, the most abundant family of nucleosome-binding proteins. Here we show that the nuclear protein HP1BP3 is widely expressed in most vertebrate tissues and is evolutionarily and structurally related to the H1 family. HP1BP3 contains three globular domains and a highly positively charged C-terminal domain, resembling similar domains in H1. Fluorescence recovery after photobleaching (FRAP) studies indicate that like H1, binding of HP1BP3 to chromatin depends on both its C and N terminal regions and is affected by the cell cycle and post translational modifications. HP1BP3 contains functional motifs not found in H1 histones, including an acidic stretch and a consensus HP1-binding motif. Transcriptional profiling of HeLa cells lacking HP1BP3 showed altered expression of 383 genes, suggesting a role for HP1BP3 in modulation of gene expression. Significantly, Hp1bp3−/− mice present a dramatic phenotype with 60% of pups dying within 24 h of birth and the surviving animals exhibiting a lifelong 20% growth retardation. We suggest that HP1BP3 is a ubiquitous histone H1 like nuclear protein with distinct and non-redundant functions necessary for survival and growth. PMID:25662603

  4. HP1BP3 is a novel histone H1 related protein with essential roles in viability and growth.

    PubMed

    Garfinkel, Benjamin P; Melamed-Book, Naomi; Anuka, Eli; Bustin, Michael; Orly, Joseph

    2015-02-27

    The dynamic architecture of chromatin is vital for proper cellular function, and is maintained by the concerted action of numerous nuclear proteins, including that of the linker histone H1 variants, the most abundant family of nucleosome-binding proteins. Here we show that the nuclear protein HP1BP3 is widely expressed in most vertebrate tissues and is evolutionarily and structurally related to the H1 family. HP1BP3 contains three globular domains and a highly positively charged C-terminal domain, resembling similar domains in H1. Fluorescence recovery after photobleaching (FRAP) studies indicate that like H1, binding of HP1BP3 to chromatin depends on both its C and N terminal regions and is affected by the cell cycle and post translational modifications. HP1BP3 contains functional motifs not found in H1 histones, including an acidic stretch and a consensus HP1-binding motif. Transcriptional profiling of HeLa cells lacking HP1BP3 showed altered expression of 383 genes, suggesting a role for HP1BP3 in modulation of gene expression. Significantly, Hp1bp3(-/-) mice present a dramatic phenotype with 60% of pups dying within 24 h of birth and the surviving animals exhibiting a lifelong 20% growth retardation. We suggest that HP1BP3 is a ubiquitous histone H1 like nuclear protein with distinct and non-redundant functions necessary for survival and growth.

  5. HP0197 contributes to CPS synthesis and the virulence of Streptococcus suis via CcpA.

    PubMed

    Zhang, Anding; Chen, Bo; Yuan, Zhengzhi; Li, Ran; Liu, Cheng; Zhou, Hongbo; Chen, Huanchun; Jin, Meilin

    2012-01-01

    Streptococcus suis serotype 2 (SS2), a major swine pathogen and an emerging zoonotic agent, has greatly challenged global public health. The encoding proteins with unknown functions the bacterium encodes are an obstruction to studies of the pathogenesis. A novel surface protective antigen HP0197 is one of these proteins which have no sequence homology to any known protein. In the present study, the protein was determined to be involved in bacterial virulence through an evaluation of the isogenic mutant (Δhp0197) in both mice and pigs. The experimental infection also indicated that Δhp0197 could be cleared easily during infection, which could be attributed to the reduced thickness of the capsular polysaccharides (CPS) and the significantly reduced phagocytotic resistance. Microarrays-based comparative transcriptome analysis suggested that the suppressed expression of the operon responsible for CPS synthesis might be reversed by CcpA activity, which controlled global regulation of carbon catabolite through the binding of the CcpA and HPr-Ser-46-P to the catabolite-responsive elements (cre) of the target operons. The hypothesis was approved by the fact that the purified FLAG-tagged HPr from WT stain exhibited a higher binding activity to cre with CcpA compared to the Δhp0197 by the Electrophoretic Mobility Shift Assay, suggesting lower level of phosphorylation of the phosphocarrier protein HPr at residue Ser-46 (HPr-Ser-46P) in Δhp0197. These indicated that HP0197 could enhance CcpA activity to control the expression of genes involved in carbohydrate utilization and CPS synthesis, thus contributing to the virulence of S. suis.

  6. Bensal HP Attenuates the Inflammatory Response in Hair Shaving Associated Dermatitis.

    PubMed

    Ray, Anjana; Mordorski, Breanne; Landriscina, Angelo; Rosen, Jamie; Nosanchuk, Joshua; Friedman, Adam

    2016-07-01

    Shaving is an ubiquitous practice, and cutaneous irritation and inflammation are common sequelae, which may be worsened by underlying skin conditions or poor hair removal techniques. Moisturizing shaving creams and aftershaves are available to help maintain or restore the epidermal barrier; however, many continue to suffer from post-shave redness, itching, and pain. To reduce post-shave inflammation, some products have included botanical and other natural ingredients, which are often favored by consumers. We evaluated Bensal HP, an ointment containing 3% oak bark extract, 3% salicylic acid, and 6% benzoic acid, which has documented anti-inflammatory and antimicrobial properties, in a murine model of shave irritation to determine whether it would be useful in this clinical setting. Shaving dermatitis was simulated using a depilatory agent and electric clippers, and the shaved area was photographed and treated with Bensal HP daily for four days. Compared to untreated controls, mice treated with Bensal HP experienced a visible reduction in skin irritation and inflammation. These findings were mirrored on histology, as Bensal HP-treated areas demonstrated increased epidermal integrity and decreased dermal inflammatory infiltrate compared to untreated skin. Using immunohistochemistry, fewer neutrophils and macrophages were noted, and cytokine analysis also revealed decreased IL-6 in Bensal HP-treated skin at 24 and 96 hours after shaving. These results highlight the potential of Bensal HP as an anti-inflammatory treatment for shave irritation. Given the product's application against a variety of inflammatory and infectious skin disorders, its use against shave irritation may also improve comorbid skin conditions, such as pseudofolliculitis barbae.

    J Drugs Dermatol. 2016;15(7):836-840.

  7. Rapid conversion of adolescent MMPI raw scores to T scores using the HP-67 programmable calculator.

    PubMed

    Hembling, D W

    1984-01-01

    Used a programmable Hewlett-Packard scientific calculator (HP-67, 97, 41C, 41CV) to rapidly convert raw scores from adolescent MMPI protocols to T scores, scale by scale. The K factor is handled, as needed, automatically. The program is stored on one side of a standard HP magnetic card. The norm data for adolescents (or optionally any other group) in the age groups less than 15, 15, 16, and 17 occupy two sides per sex per age group of eight magnetic data cards. Complete scoring and profiling of the R-form MMPI can be done in less than 10 minutes.

  8. Phase 3 evaluation of HP802-247 in the treatment of chronic venous leg ulcers.

    PubMed

    Kirsner, Robert S; Vanscheidt, Wolfgang; Keast, David H; Lantis, John C; Dove, Cyaandi R; Cazzell, Shawn M; Vartivarian, Mher; Augustin, Matthias; Marston, William A; McCoy Bs, Nicholas D; Cargill PhD, D Innes; Lee Mshs, Tommy D; Dickerson, Jaime E; Slade Md, Herbert B

    2016-09-01

    In 2012 we reported promising results from a phase 2 clinical trial of HP802-247, a novel spray-applied investigational treatment for chronic venous leg ulcers consisting of human, allogeneic fibroblasts and keratinocytes. We now describe phase 3 clinical testing of HP802-247, its failure to detect efficacy, and subsequent investigation into the root causes of the failure. Two randomized, controlled trials enrolled a total of 673 adult outpatients at 96 centers in North America and Europe. The primary endpoint was the proportion of ulcers with confirmed closure at the end of 12 weeks of treatment. An investigation into the root cause for the failure of HP802-247 to show efficacy in these two phase 3 trials was initiated immediately following the initial review of the North American trial results. Four hundred twenty-one patients were enrolled in the North American (HP802-247, 211; Vehicle 210) and 252 in the European (HP802-247, 131; Vehicle 121) trials. No difference in proportion of closed ulcers at week 12 was observed between treatment groups for either the North American (HP802-247, 61.1%; Vehicle 60.0%; p = 0.5896) or the European (HP802-247, 47.0%; Vehicle 50.0%; p = 0.5348) trials. Thorough investigation found no likelihood that design or execution of the trials contributed to the failure. Variability over time during the trials in the clinical response implicated the quality of the cells comprising HP802-247. Concordance between the two separate, randomized, controlled trials with distinct, nonoverlapping investigative sites and independent monitoring teams renders the possibility of a Type II error vanishingly small and provides strong credibility for the unexpected lack of efficacy observed. The most likely causative factors for the efficacy failure in phase 3 was phenotypic change in the cells (primarily keratinocytes) leading to batch to batch variability due to the age of the cell banks.

  9. Red variables in the Hipparcos HpV-T2 system: lessons learned

    NASA Astrophysics Data System (ADS)

    Platais, I.; Pourbaix, D.; Jorissen, A.; Makarov, V. V.

    2003-03-01

    For 4785 M, 50 S, and 321 C stars from Hipparcos Catalogue, we provide calibrated Cousins V-I color indices using the newly derived Hp-V-T2 color. The standard error of the mean V-I is 0.1 mag or better down to Hp 9. This photometry can be used to explore the chromaticity effects on the Hipparcos astrometry of red stars with extreme colors. It can also help to solve some problematic cases in the Hipparcos Catalogue, involving a red variable star in a real or a possible binary system.

  10. hp-DPI: Helicobacter pylori database of protein interactomes--embracing experimental and inferred interactions.

    PubMed

    Lin, Chung-Yen; Chen, Chia-Ling; Cho, Chi-Shiang; Wang, Li-Ming; Chang, Chia-Ming; Chen, Pao-Yang; Lo, Chen-Zen; Hsiung, Chao A

    2005-04-01

    We implemented a statistical model into our protein interaction database for validation of two-hybrid assays of Helicobacter pylori, and prediction of putative protein interactions not yet discovered experimentally. To present the enormous amount of experimental and inferred protein interaction networking maps, the H.pylori Database of Protein Interactomes (hp-DPI) is developed with a succinct yet comprehensive visualization tool integrated with annotation from Genbank, GO, and KEGG. hp-DPI is first built with, but not limited to, H.pylori protein interactions and is expected to naturally include other organisms' protein interacting relationships in the future.

  11. An hp -local discontinuous Galerkin method for some quasilinear elliptic boundary value problems of nonmonotone type

    NASA Astrophysics Data System (ADS)

    Gudi, Thirupathi; Nataraj, Neela; Pani, Amiya K.

    2008-06-01

    In this paper, an hp -local discontinuous Galerkin method is applied to a class of quasilinear elliptic boundary value problems which are of nonmonotone type. On hp -quasiuniform meshes, using the Brouwer fixed point theorem, it is shown that the discrete problem has a solution, and then using Lipschitz continuity of the discrete solution map, uniqueness is also proved. A priori error estimates in broken H^1 norm and L^2 norm which are optimal in h , suboptimal in p are derived. These results are exactly the same as in the case of linear elliptic boundary value problems. Numerical experiments are provided to illustrate the theoretical results.

  12. Effects of magnetic fields on improving mass transfer in flue gas desulfurization using a fluidized bed

    NASA Astrophysics Data System (ADS)

    Zhang, Qi; Gui, Keting; Wang, Xiaobo

    2016-02-01

    The effects of magnetic fields on improving the mass transfer in flue gas desulfurization using a fluidized bed are investigated in the paper. In this research, the magnetically fluidized bed (MFB) is used as the reactor in which ferromagnetic particles are fluidized with simulated flue gas under the influence of an external magnetic field. Lime slurry is continuously sprayed into the reactor. As a consequence, the desulfurization reaction and the slurry drying process take place simultaneously in the MFB. In this paper, the effects of ferromagnetic particles and external magnetic fields on the desulphurization efficiency are studied and compared with that of quartz particles as the fluidized particles. Experimental results show that the ferromagnetic particles not only act as a platform for lime slurry to precipitate on like quartz particles, but also take part in the desulfurization reaction. The results also show that the specific surface area of ferromagnetic particles after reaction is enlarged as the magnetic intensity increases, and the external magnetic field promotes the oxidation of S(IV), improving the mass transfer between sulphur and its sorbent. Hence, the efficiency of desulphurization under the effects of external magnetic fields is higher than that in general fluidized beds.

  13. [Domestication study about desulfuration microorganism from oxidation ditch by low concentration SO2].

    PubMed

    Huang, Bing; Shi, Zhe; Wang, Yan-Yan; Zhang, Shi-Ling

    2010-06-01

    An excellent desulfuration microorganism with a quick growth and propagation, high activation, high efficiency of removing SO2 is obtained from oxidation ditch of a city sewage treatment plant by inductive acclimatization over 6 d with low concentration SO2 gas (100-2 000 mg/m3). The desulfurition microorganism get their energy sources for growth from transforming SO2 (SO3(2-)) to SO4(2-). The predominant bacterium of the desulfuration microorganism has the same characteristic with Thiobacillus ferrooxidans (T. ferrooxidans), which showed that it was Gram negative, short rod bacteria with a single polar flagellum under a microscopic examination, and obtained its nourishment through the oxidation of inorganic compounds. The technology process condition of domestication and desulfuration of microorganism are particular studied, and the results showed that aerating time, SO2 flux and time to provide nutriment contained N, P, K to microorganism were very important. They have an ability with degradation rate of 160g/ (m3 x h) and degradation efficiency over 50% to transform sulfite to sulfate in liquid phase. The bacteria have a 98% of removing efficiency and over 80% of biodegradation efficiency for the 5 500 mg/m3 SO2 gas and the outlet concentration of SO2 is lower than 100 mg/m3, and also have a 95% of removing efficiency for 15 000 mg/m3 SO2 gas in the packed tower reactor with Raschig ring at 3s contact time.

  14. Enhanced pervaporative desulfurization by polydimethylsiloxane membranes embedded with silver/silica core-shell microspheres.

    PubMed

    Cao, Ruijian; Zhang, Xiongfei; Wu, Hong; Wang, Jingtao; Liu, Xiaofei; Jiang, Zhongyi

    2011-03-15

    Pervaporative desulfurization based on membrane technology provides a promising alternative for removal of sulfur substances (as represented by thiophene) in fluid catalytic cracking (FCC) gasoline. The present study focused on the performance enhancement of polydimethylsiloxane (PDMS) membrane by incorporation of core-shell structured silver/silica microspheres. A silane coupling agent, N-[3-(trimethoxysily)propyl]-ethylenediamine (TSD), was used to chelate the Ag(+) via its amino groups and attach the silver seeds onto the silica surface via condensation of its methoxyl groups. The resultant microspheres were characterized by Zeta-positron annihilation lifetime spectroscopy (ZetaPALS), inductively coupled plasmaoptical emission spectrophotometer (ICP), transmission electron microscopy (TEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The Ag(+)/SiO(2)-PDMS composite membranes were prepared by blending PDMS with the as-synthesized silver/silica microspheres. PALS analysis was used to correlate the apparent fractional free volume with permeation flux. The sorption selectivity towards thiophene was enhanced after incorporation of silver/silica microspheres due to the π-complexation between the silver on the microsphere surface and the thiophene molecules. The pervaporative desulfurization performance of the composite membrane was investigated using thiophene/n-octane mixture as a model gasoline. The composite membrane exhibited an optimum desulfurization performance with a permeation flux of 7.76 kg/(m(2)h) and an enrichment factor of 4.3 at the doping content of 5%.

  15. Competitive adsorption desulfurization performance over K - Doped NiY zeolite.

    PubMed

    Li, Haizheng; Han, Xiaona; Huang, Haokai; Wang, Yuxian; Zhao, Liang; Cao, Liyuan; Shen, Baojian; Gao, Jinsen; Xu, Chunming

    2016-12-01

    NiY and KNiY were successfully prepared by impregnation method and characterized by X-ray diffraction (XRD), N2 sorption (BET), scanning electron microscope (SEM), infrared spectrum (IR) and X-ray Photoelectron Spectroscopy (XPS). The competitive adsorption mechanisms of adsorbents were studied by in situ FTIR to explain different desulfurization performance which was evaluated in a miniature fixed-bed flow by gasoline model compounds with 1-hexene or toluene. NiY and KNiY adsorbents showed better desulfurization performance than HY zeolite due to the high selectivity of loaded active metals. Especially, KNiY adsorbent showed its advantages in desulfurization performance with 5vol% olefins or 5vol% aromatics involvement. It could be assigned that introduced K cation enhanced dispersion and content of active Ni species on the surface which made Ni species reduce easily. On the other hand, adsorption mechanisms showed that the protonation reactions of thiophene and 1-hexene occurred on the Brönsted acid sites of NiY, which resulted in pore blockage and the coverage of adsorption active centers. By doping K cation on NiY, the amount of the Brönsted acid sites of NiY was decreased and protonation reactions were weaken. Therefore, the negative effects of Brönsted acid sites were reduced.

  16. Catalytic Emulsion Based on Janus Nanosheets for Ultra-Deep Desulfurization.

    PubMed

    Xia, Lixin; Zhang, Hairan; Wei, Zhichao; Jiang, Yi; Zhang, Ling; Zhao, Jie; Zhang, Junhui; Dong, Li; Li, Erni; Ruhlmann, Laurent; Zhang, Qian

    2017-02-03

    Catalytic Janus nanosheets were synthesized by using an anion-exchange reaction between heteropolyacids (HPAs) and the modified ionic-liquid (IL) moieties of Janus nanosheets. Their morphology and surface properties were characterized by using SEM, energy-dispersive spectroscopy (EDS), FTIR spectroscopy, and X-ray photoelectron spectroscopy (XPS) studies. Because of their inherent Janus structure, the nanosheets exhibited good amphipathic character with ILs and oil to form a stable ILs-in-oil emulsion. Therefore, these Janus nanosheets can be used as both emulsifiers and catalysts to perform emulsive desulfurization. During this process, sulfur-containing compounds at the interface could be easily oxidized and efficiently removed from a model oil. Application of this Janus emulsion brings an efficient, useful, and green procedure to the desulfurization process. Compared with the desulfurization catalyzed by using HPAs in a conventional two-phase system, the sulfur removal of dibenzothiophene (DBT) achieved in a Janus emulsion system was improved from 68 to 97 % within 1.5 h. Moreover, this emulsion system could be demulsified easily by simple centrifugation to recover both the nanosheets and the ILs. Owing to the good structural stability of the Janus nanosheets, the sulfur removal efficiency of DBT could still reach 99.9 % after the catalytic nanosheets had been recycled at least six times.

  17. Bench-scale development of mild gasification char desulfurization; [Quarterly] report, September 1--November 30, 1993

    SciTech Connect

    Knight, R.A.

    1994-03-01

    This goal of this project is to scale up a process, developed under a previous ICCI grant, for desulfurization of mild gasification char by treatment with hydrogen-rich process-derived fuel gas at 650{degree}--760{degree}C and 7-15 atm. The char can be converted into a low-sulfur metallurgical form coke. In the prior study, IBC-105 coal with 4.0 wt % sulfur was converted to chars with less than 1.0 wt % sulfur in a laboratory-scale batch reactor. The susceptibility of the char to desulfurization was correlated with physicochemical char properties and mild gasification conditions. Acid pretreatment of the coal prior to mild gasification was also shown to significantly enhance subsequent sulfur removal. In this study, IGT is conducting continuous bench-scale tests in a 1-lb/h fluidized-bed reactor to determine the preferred process conditions and obtain steady-state data necessary for process design and scale-up. The desulfurized chars are to be used to produce low-sulfur form coke, which will be evaluated for density, reactivity, and strength properties relevant to utilization in blast furnaces. During the first quarter, 180 lb (82 kg) of IBC-105 coal was obtained and subjected to crushing, and sizing to prepare 49 lb (22 kg) of material for test operation.

  18. Preparation of Ag/TiO2-zeolite adsorbents, their desulfurization performance, and benzothiophene adsorption isotherms

    NASA Astrophysics Data System (ADS)

    Song, Hua; Yang, Gang; Song, Hua-Lin; Wang, Deng; Wang, Xue-Qin

    2017-02-01

    A series of Ag/TiO2-NaY (TY) composite adsorbents were successfully prepared and characterized by X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, BET, scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) techniques. The effects of TiO2 and Ag contents on the structure and desulfurization performance of NaY zeolite were studied. The results show that anatase phase is the main form of TiO2 in AgTY adsorbent, and the Y-zeolite framework remained unchanged. AgTY with 6 wt % of Ag and 50 wt % of TiO2 exhibited the best desulfurization performance with the effluent volume of 63.2 mL/g at 10 mg/L sulfur breakthrough level (desulfurization rate of 95%). The benzothiophene (BT) removal performance of the various adsorbents follows the order: NaY < TiO2 < TY-50 < AgTY-50-6. The equilibrium data were modeled by Langmuir and Freundlich equations. The Langmuir model can describe well the adsorption isotherms of BT over AgTY.

  19. METC`s pilot-scale hot-gas desulfurization Process Development Unit

    SciTech Connect

    McMillian, M.H.; Bissett, L.A.

    1996-12-31

    801The Morgantown Energy Technology Center (METC) has designed and is currently constructing an on-site, hot gas desulfurization (HGD) Process Development Unit (PDU). The PDU is designed to use regenerable solid metal oxide sorbents that absorb hydrogen sulfide from high-temperature, high-pressure simulated coal-gasification fuel gas that is generated by a METC-designed syngas generator. The simulated coal gas is a mixture of partially combusted natural gas, water, carbon dioxide and hydrogen sulfide. PDU process conditions will be representative of anticipated commercial applications in terms of temperatures, pressures, compositions, velocities, and sorbent cycling. The PDU supports the Integrated Gasification Combined Cycle (IGCC) mission at METC by providing a test bed for development of IGCC cleanup systems that offer low capital cost, operating costs, and costs of electricity. METC intends to develop additional industrial involvement opportunities as the project progresses towards operations. Objectives The primary objectives of the PDU are to: (1) fill the gap between small-scale testing and large-scale demonstration projects by providing a cost effective test site for transport and fluid-bed desulfurization reactor and sorbent development, (2) demonstrate sorbent suitability over a wide range of parameters and (3) generate significant information on process control for transport and fluidized bed based desulfurization. PDU data is expected to be used to optimize process performance by expanding the experience for larger-scale demonstration projects, such as Sierra Pacific Power Company`s Clean Coal Technology project.

  20. Desulfurization of dibenzothiophene by a newly isolated Corynebacterium sp. ZD-1 in aqueous phase.

    PubMed

    Wang, Miao-Dong; Li, Wei; Wang, Da-Hui; Shi, Yao

    2004-01-01

    Sulfur emission through fuel combustion is a global problem because it is a major cause of acid rain. Crud oil contains many heterocyclic organic sulfur compounds, among which dibenzothiophene (DBT) and DBTs bearing alkyl substitutions usually are representative compounds. A strain was isolated from refinery sludge and identified as Corynebacterium ZD-1. The behavior of DBT degradation by ZD-1 in aqueous phase was investigated. Corynebacterium ZD-1 could metabolize DBT to 2-hydroxybiphenyl(2-HBP) as the dead-end metabolite through a sulfur-specific pathway. In shake flask culture, ZD-1 had its maximal desulfurization activity in the late exponential growth phase and the specific production rate of 2-HBP was about 0.14 (mmol x kg dry cell(-1) x min(-1), mmol x KDC(-1) x min(-1)). Active resting cells for desulfurization should be prepared only in this period. 2-HBP inhibited the growth of strain ZD-1, the production of DBT degradation enzymes, and the activity of enzymes. Sulfate inhibited the production of dibenzothiophene (DBT) degradation enzymes but had no effect on the enzymes' activity. The production rates of 2-HBP at lower cell densities were higher and the maximum amount conversion of DBT to 2-HBP (0.067 mmol/L) after 8 h was gained at 9.2 g dry cell/L rather higher cell density. The results indicated that this newly isolated strain could be a promising biocatalyst for DBT desulfurization.

  1. [Research on desulfurization using coke-oven wastewater with pulsed corona discharge].

    PubMed

    Shao, Gui-wei; Li, Jin; Wang, Wan-lin; Li, Sheng-li

    2004-03-01

    A recent investigation into the application of pulsed corona discharge process, in which simultaneous SO2 removal from simulated flue gas and coke-oven wastewater degradation, was conducted at Wuhan Integrated Steel Plant. The outcome indicates that coke-oven wastewater had good desulfurization ability, and SO2 removal efficiency increased gradually as the simulated flue gas temperature increasing in the temperature range used during the experiment. When the flow of simulated flue gas was 428 m3/h, the temperature of simulated flue gas was 65 degrees C and coke-oven wastewater flow was 107 L/h, the desulfurization rate was 85%. Introducing pulsed corona discharge to the reactor enhanced the removal efficiencies of SO2, the desulfurization rate increased to 90% when high voltage was 52kV. When SO2 was removed from simulated flue gas by pulsed corona discharge, oil and phenols content in coke-oven wastewater decreased 39.26% and 68.75% respectively, and 99.98% content of cyanide was degraded, which is of important value in solving the inactivation problem of aerobic bacteria in biological treatment of coke-oven wastewater.

  2. Highly stable and regenerable Mn-based/SBA-15 sorbents for desulfurization of hot coal gas.

    PubMed

    Zhang, F M; Liu, B S; Zhang, Y; Guo, Y H; Wan, Z Y; Subhan, Fazle

    2012-09-30

    A series of mesoporous xCuyMn/SBA-15 sorbents with different Cu/Mn atomic ratios were prepared by wet impregnation method and their desulfurization performance in hot coal gas was investigated in a fixed-bed quartz reactor in the range of 700-850°C. The successive nine desulfurization-regeneration cycles at 800°C revealed that 1Cu9Mn/SBA-15 presented high performance with durable regeneration ability due to the high dispersion of Mn(2)O(3) particles incorporated with a certain amount of copper oxides. The breakthrough sulfur capacity of 1Cu9Mn/SBA-15 observed 800°C is 13.8 g S/100g sorbents, which is remarkably higher than these of 40 wt%LaFeO(3)/SBA-15 (4.8 g S/100g sorbents) and 50 wt%LaFe(2)O(x)/MCM-41 (5.58 g S/100g sorbents) used only at 500-550°C. This suggested that the loading of Mn(2)O(3) active species with high thermal stability to SBA-15 support significantly increased sulfur capacity at relatively higher sulfidation temperature. The fresh and used xCuyMn/SBA-15 sorbents were characterized by means of BET, XRD, XPS, XAES, TG/DSC and HRTEM techniques, confirmed that the structure of the sorbents remained intact before and after hot coal gas desulfurization.

  3. Removal of polychlorinated naphthalenes by desulfurization and emissions of polychlorinated naphthalenes from sintering plant

    PubMed Central

    Wang, Mengjing; Liu, Wenbin; Hou, Meifang; Li, Qianqian; Han, Ying; Liu, Guorui; Li, Haifeng; Liao, Xiao; Chen, Xuebin; Zheng, Minghui

    2016-01-01

    The sintering flue gas samples were collected at the inlets and outlets of the desulfurization systems to evaluate the influence of the systems on PCNs emission concentrations, profiles, and emission factors. The PCNs concentrations at the inlets and outlets were 27888–153672 pg m−3 and 11988–42245 pg m−3,respectively. Desulfurization systems showed excellent removal for PCNs, and the removal efficiencies of PCNs increase with increasing chlorination level. Lower chlorinated homologs are more sensitive to the desulfurization process than higher ones. High levels of PCNs were also detected in the gypsum (11600–29720 pg g−1) and fly ash samples (4946–64172 pg g−1). The annual total emissions of PCNs released to flue gas and gypsum from the sintering plants were about 394 kg, 48.5% of which was in gypsum. The surface area of the fly ash samples increased significantly from the first to the fourth stage of the series-connected electrostatic precipitator, accompanying obvious rising of concentration of PCNs in the fly ash samples. PMID:27197591

  4. Numerical simulation and field test study of desulfurization wastewater evaporation treatment through flue gas.

    PubMed

    Deng, Jia-Jia; Pan, Liang-Ming; Chen, De-Qi; Dong, Yu-Quan; Wang, Cheng-Mu; Liu, Hang; Kang, Mei-Qiang

    2014-01-01

    Aimed at cost saving and pollution reduction, a novel desulfurization wastewater evaporation treatment system (DWETS) for handling wet flue gas desulfurization (WFGD) wastewater of a coal-fired power plant was studied. The system's advantages include simple process, and less investment and space. The feasibility of this system has been proven and the appropriate position and number of nozzles, the spray droplet size and flue gas temperature limitation have been obtained by computational fluid dynamics (CFD) simulation. The simulation results show that a longer duct, smaller diameter and higher flue gas temperature could help to increase the evaporation rate. The optimal DWETS design of Shangdu plant is 100 μm droplet sprayed by two nozzles located at the long duct when the flue gas temperature is 130 °C. Field tests were carried out based on the simulation results. The effects of running DWETS on the downstream devices have been studied. The results show that DWETS has a positive impact on ash removal efficiency and does not have any negative impact on the electrostatic precipitator (ESP), flue gas heat exchanger and WFGD. The pH values of the slurry of WFGD slightly increase when the DWETS is running. The simulation and field test of the DWETS show that it is a feasible future technology for desulfurization wastewater treatment.

  5. Semi-wet flue gas desulfurization with a multi-solid fluidized bed

    SciTech Connect

    Lei, Z.; Wu, C.; Xu, B.; Chen, Y.; Liu, B.

    1997-12-31

    In this study, the authors put forward a new flue gas desulfurization process with a Multi-Solid Fluidized Bed. The principle of the method is as follows. The flue gas is supplied to the bottom of the fluidized bed and lime/limestone slurry is dropped from the top to a bed of the coarse particles. The slurry is uniformly dispersed in the bed by the fluidizing coarse particles, so that the slurry can make contact with the flue gas sufficiently. Dried fine particles of desulfurization product are entrained to the gas-solid separator. In this system, the drying process of the slurry is a key point. During the primary work, they investigated the drying mechanism of the limestone slurry containing fine particles in the coarse particle bed. The desulfurization performance of a simulated flue gas has been carried out. It is concluded that: (1) the drying process of the slurry is mainly one of the water involved; (2) the slurry drying process can be separated into two steps with constant and decreasing velocity, respectively; and (3) using this apparatus, more than 95% SO{sub 2} removal can be obtained when Ca/S equals 2.

  6. A multicomponent assembly approach for the design of deep desulfurization heterogeneous catalysts.

    PubMed

    Xu, Yanqi; Xuan, Weimin; Zhang, Mengmeng; Miras, Haralampos N; Song, Yu-Fei

    2016-12-06

    Deep desulfurization is a challenging task and global efforts are focused on the development of new approaches for the reduction of sulfur-containing compounds in fuel oils. In this work, we have proposed a new design strategy for the development of deep desulfurization heterogeneous catalysts. Based on the adopted design strategy, a novel composite material of polyoxometalate (POM)-based ionic liquid-grafted layered double hydroxides (LDHs) was synthesized by an exfoliation/grafting/assembly process. The structural properties of the as-prepared catalyst were characterized using FT-IR, XRD, TG, NMR, XPS, BET, SEM and HRTEM. The heterogeneous catalyst exhibited high activity in deep desulfurization of DBT (dibenzothiophene), 4,6-DMDBT (4,6-dimethyldibenzothiophene) and BT (benzothiophene) at 70 °C in 25, 30 and 40 minutes, respectively. The catalyst can be easily recovered and reused at least ten times without obvious decrease of its catalytic activity. Such excellent sulfur removal ability as well as the cost efficiency of the novel heterogeneous catalyst can be attributed to the rational design, where the spatial proximity of the substrate and the active sites, the immobilization of ionic liquid onto the LDHs via covalent bonding and the recyclability of the catalyst are carefully considered.

  7. Preliminary evaluation of a process using plasma reactions to desulfurize heavy oils. Final report

    SciTech Connect

    Grimes, P.W.; Miknis, F.P.

    1997-09-01

    Western Research Institute (WRI) has conducted exploratory experiments on the use of microwave-induced plasmas to desulfurize heavy oils. Batch mode experiments were conducted in a quartz reactor system using various reactive and nonreactive plasmas. In these experiments a high-sulfur asphalt was exposed to various plasmas, and the degree of conversion to distillate, gas, and solids was recorded. Products from selected experiments were analyzed to determine if the plasma exposure had resulted in a significant reduction in sulfur content. Exploratory experiments were conducted using reactive plasmas generated from hydrogen and methane and nonreactive plasmas generated from nitrogen. The effects of varying exposure duration, sample temperature, and location of the sample with respect to the plasma discharge were investigated. For comparative purposes two experiments were conducted in which the sample was heated under nitrogen with no plasma exposure. Distillates containing approximately 28% less sulfur than the feedstock represented the maximum desulfurization attained in the plasma experiments. It does not appear that plasma reactions using the simple configurations employed in this study represent a viable method for the desulfurization of heavy oils.

  8. Integrating desulfurization with CO{sub 2}-capture in chemical-looping combustion

    SciTech Connect

    Solunke, Rahul; Veser, Goetz

    2011-02-01

    Chemical looping combustion (CLC) is an emerging technology for clean combustion. We have previously demonstrated that the embedding of metal nanoparticles into a nanostructured ceramic matrix can result in unusually active and sinter-resistant nanocomposite oxygen carrier materials for CLC which maintain high reactivity and high-temperature stability even when sulfur contaminated fuels are used in CLC. Here, we propose a novel process scheme for in situ desulfurization of syngas with simultaneous CO{sub 2}-capture in chemical looping combustion by using these robust nanocomposite oxygen carriers simultaneously as sulfur-capture materials. We found that a nanocomposite Cu-BHA carrier can indeed strongly reduce the H{sub 2}S concentration in the fuel reactor effluent. However, during the process the support matrix is also sulfidized and takes part in the redox process of CLC. This results in SO{sub 2} production during the reduction of the oxygen carrier and thus limits the degree of desulfurization attainable with this kind of carrier. Nevertheless, the results suggest that simultaneous desulfurization and CO{sub 2} capture in CLC is feasible with Cu as oxygen carrier as long as appropriate carrier support materials are chosen, and could result in a novel, strongly intensified process for low-emission, high efficiency combustion of sulfur contaminated fuel streams.

  9. Desulfurization of aromatic sulfonates by rhizosphere bacteria: high diversity of the asfA gene.

    PubMed

    Schmalenberger, Achim; Kertesz, Michael A

    2007-02-01

    The plant growth-promoting effect of Pseudomonas putida S-313 is associated with its ability to desulfurize arylsulfonates. To understand this further, other plant-associated bacteria able to desulfurize a range of arylsulfonates were isolated from the rhizospheres of winter and spring barley. The isolates belonged to the beta-proteobacteria, including bacteria from the Variovorax paradoxus group and from the Acidovorax genus. They desulfurized toluenesulfonate to p-cresol, and were found to contain orthologues of the P. putida S-313 asfA gene (> 70% sequence identity to AsfA), which is required for aryldesulfonation in this species. Further putative asfA orthologues were identified in several bacteria and cyanobacteria whose genomes have been sequenced, but of these only Cupriavidus (Ralstonia) metallidurans was able to utilize arylsulfonates as sulfur source. Cultivation of V. paradoxus, C. metallidurans or P. putida S-313 with toluenesulfonate as sulfur source led to a 100-fold increase in expression of the asfA homologues, which was largely repressed when sulfate was added. Polymerase chain reaction with degenerate primers was used to generate asfAB clone libraries from spring- and winter-barley rhizosphere DNA. Cluster analysis of 76 sequenced AsfA fragments revealed a broad diversity, with the majority of the sequences clustered together with AsfA from bacteria that are able to utilize toluenesulfonate as sulfur source. The diversity of asfA in barley rhizosphere underlines the importance of the desulfonation process for bacteria that inhabit the plant rhizosphere.

  10. Hot-gas desulfurization. II. Use of gasifier ash in a fluidized-bed process. Final report

    SciTech Connect

    Schrodt, J.T.

    1981-02-01

    Three gasifier coal ashes were used as reactant/sorbents in batch fluidized-beds to remove hydrogen sulfide from hot, made-up fuel gases. It is predominantly the iron oxide in the ash that reacts with and removes the hydrogen sulfide; the sulfur reappears in ferrous sulfide. Sulfided ashes were regenerated by hot, fluidizing streams of oxygen in air; the sulfur is recovered as sulfur dioxide, exclusively. Ash sorption efficiency and sulfur capacity increase and stabilize after several cycles of use. These two parameters vary directly with the iron oxide content of the ash and process temperature, but are independent of particle size in the range 0.01 - 0.02 cm. A western Kentucky No. 9 ash containing 22 weight percent iron as iron oxide sorbed 4.3 weight percent sulfur at 1200/sup 0/F with an ash sorption efficiency of 0.83 at ten percent breakthrough. A global, fluidized-bed, reaction rate model was fitted to the data and it was concluded that chemical kinetics is the controlling mechanism with a predicted activation energy of 19,600 Btu/lb mol. Iron oxide reduction and the water-gas-shift reaction were two side reactions that occurred during desulfurization. The regeneration reaction occurred very rapidly in the fluid-bed regime, and it is suspected that mass transfer is the controlling phenomenon.

  11. AFRL’s HP3 60mm Powder Gun

    DTIC Science & Technology

    2012-08-08

    the phenolic body, which is a hollow tube of grade LE linen -phenolic for the high speed projectile, with an inner diameter of 1.5 inches. During...as opposed to hollow) rod of grade LE linen phenolic. The rear is drilled and tapped to directly accept the stud from the boot, so no aluminum rear...for less drag in the barrel (and therefore less deceleration). It should be noted that although the high and low speed projectiles use grade LE linen

  12. 29. INDUCTION MOTOR (6600 VOLTS, 5750 H.P.) DRIVES THE 21INCH ...

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

    29. INDUCTION MOTOR (6600 VOLTS, 5750 H.P.) DRIVES THE 21-INCH AND 18-INCH BILLET MILLS. MOTOR WAS MANUFACTURED BY THE GENERAL ELECTRIC COMPANY, SCHENECTADY, NEW YORK. - Corrigan, McKinney Steel Company, 3100 East Forty-fifth Street, Cleveland, Cuyahoga County, OH

  13. DETAIL OF GENERAL ELECTRIC 250HP SYNCHRONOUS MOTOR FROM DRIVE END. ...

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

    DETAIL OF GENERAL ELECTRIC 250-HP SYNCHRONOUS MOTOR FROM DRIVE END. MOTOR BADGE PLATE READS 263 AMP, 400 VOLT, FRAME 6274-D #4940649, 250 HORSEPOWER, TYPE TSR, 3 PHASE, 60 CYCLE, SPEED 300 RPM. - Shenandoah-Dives Mill, 135 County Road 2, Silverton, San Juan County, CO

  14. Detail, unit 4, 1,850 horsepower (hp) synchronous pump motor manufactured ...

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

    Detail, unit 4, 1,850 horsepower (hp) synchronous pump motor manufactured by The Electric Products Company, Cleveland , Ohio. Pump units 1, 2, and 3 are identical to this unit. View to the west - Wellton-Mohawk Irrigation System, Pumping Plant No. 3, South of Interstate 8, Wellton, Yuma County, AZ

  15. Detail, unit 4, 3,000 hp synchronous pump motor. Manufactured by ...

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

    Detail, unit 4, 3,000 hp synchronous pump motor. Manufactured by The Electric Products Company, Cleveland, Ohio. Unit 5 is identical to this unit - Wellton-Mohawk Irrigation System, Pumping Plant No. 2, Bounded by Interstate 8 to south, Wellton, Yuma County, AZ

  16. Detail, unit 3, 1,100 horsepower (hp) pump motor. Manufactured by ...

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

    Detail, unit 3, 1,100 horsepower (hp) pump motor. Manufactured by the Electric Products Company, Cleveland, Ohio, USA. Units 1,2, and 4 are identical to this unit - Wellton-Mohawk Irrigation System, Pumping Plant No. 1, Bounded by Gila River & Union Pacific Railroad, Wellton, Yuma County, AZ

  17. Detail, unit 1, 3,000 horsepower (hp) synchronous pump motor. Manufactured ...

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

    Detail, unit 1, 3,000 horsepower (hp) synchronous pump motor. Manufactured by The Electric Machinery Manufacturing Company, Minneapolis, Minnesota. Units 2 and 3 are identical to this unit - Wellton-Mohawk Irrigation System, Pumping Plant No. 2, Bounded by Interstate 8 to south, Wellton, Yuma County, AZ

  18. 10. BOILER #16 (BUILDING L8) TO LEFT, L.P. AND H.P. ...

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

    10. BOILER #16 (BUILDING L8) TO LEFT, L.P. AND H.P. BOILER ROOMS (BUILDINGS L4 AND L2) TO RIGHT, AND STEPHENS SUBSTATION (BUILDING L6) IN BACKGROUND, FROM THE ROOF OF THE POWERHOUSE EXTENSION (BUILDING L5) - Portland General Electric Company, Station "L", 1841 Southeast Water Street, Portland, Multnomah County, OR

  19. Critical Success Factors in Crafting Strategic Architecture for E-Learning at HP University

    ERIC Educational Resources Information Center

    Sharma, Kunal; Pandit, Pallvi; Pandit, Parul

    2011-01-01

    Purpose: The purpose of this paper is to outline the critical success factors for crafting a strategic architecture for e-learning at HP University. Design/methodology/approach: A descriptive survey type of research design was used. An empirical study was conducted on students enrolled with the International Centre for Distance and Open Learning…

  20. Strategic Architecture for E-Learning at H.P. University

    ERIC Educational Resources Information Center

    Sharma, Kunal; Sood, Deepak; Singh, Amarjeet; Pandit, Pallvi

    2010-01-01

    Purpose: The purpose of the paper is to unravel a strategic architecture for e-learning for a traditional university like Himachal Pradesh University (H.P. University) and provide guidelines as to how to carry the implementation of e-learning for the university of the future. Design/methodology/approach: Getting to the future first is not just…

  1. New approach to calculate the true-coincidence effect of HpGe detector

    SciTech Connect

    Alnour, I. A. E-mail: ibrahim.elnour@yahoo.com; Wagiran, H.; Ibrahim, N.; Hamzah, S.; Elias, M. S.; Siong, W. B.

    2016-01-22

    The corrections for true-coincidence effects in HpGe detector are important, especially at low source-to-detector distances. This work established an approach to calculate the true-coincidence effects experimentally for HpGe detectors of type Canberra GC3018 and Ortec GEM25-76-XLB-C, which are in operation at neutron activation analysis lab in Malaysian Nuclear Agency (NM). The correction for true-coincidence effects was performed close to detector at distances 2 and 5 cm using {sup 57}Co, {sup 60}Co, {sup 133}Ba and {sup 137}Cs as standard point sources. The correction factors were ranged between 0.93-1.10 at 2 cm and 0.97-1.00 at 5 cm for Canberra HpGe detector; whereas for Ortec HpGe detector ranged between 0.92-1.13 and 0.95-100 at 2 and 5 cm respectively. The change in efficiency calibration curve of the detector at 2 and 5 cm after correction was found to be less than 1%. Moreover, the polynomial parameters functions were simulated through a computer program, MATLAB in order to find an accurate fit to the experimental data points.

  2. Study of the inclusion interaction of HP-γ-cyclodextrin with bupropion and its analytical application

    NASA Astrophysics Data System (ADS)

    Misiuk, Wieslawa; Jasiuk, Emilia

    2014-02-01

    Inclusion complex formation between bupropion (BUP) and hydroxypropyl-γ-cyclodextrin (HP-γ-CD) was studied by Fourier transformation infrared (FT-IR), nuclear magnetic resonance (NMR) and UV spectroscopy. The main factors affecting inclusion interaction were discussed in detail. The inclusion complex of bupropion and hydroxypropyl-γ-cyclodextrin was studied at pH 5 in aqueous phase. Stoichiometry of the complex was found to be 1:1 and apparent formation constant (log K) was determined as 3.54 ± 0.01, suggesting a tendency of the drug to enter HP-γ-CD cavity. All obtained information proved the formation of BUP/HP-γ-CD inclusion complex. A significant enhancement of absorption intensity of bupropion in presence of HP-γ-CD was shown. Due to the property a sensitive spectrophotometric method was elaborated for determination of active substance in bulk solution. At optimum experimental conditions, a linear relationship between absorbance and concentration of bupropion is observed in range of 4-60 μg mL-1 with limit detection of 0.32 μg mL-1 and correlation coefficient of 0.9991. The proposed method was applied successfully to the determination of BUP in pharmaceutical preparations and the results were satisfactory in comparison to official method.

  3. Displacement of D1, HP1 and topoisomerase II from satellite heterochromatin by a specific polyamide.

    PubMed

    Blattes, Roxane; Monod, Caroline; Susbielle, Guillaume; Cuvier, Olivier; Wu, Jian-hong; Hsieh, Tao-shih; Laemmli, Ulrich K; Käs, Emmanuel

    2006-06-07

    The functions of DNA satellites of centric heterochromatin are difficult to assess with classical molecular biology tools. Using a chemical approach, we demonstrate that synthetic polyamides that specifically target AT-rich satellite repeats of Drosophila melanogaster can be used to study the function of these sequences. The P9 polyamide, which binds the X-chromosome 1.688 g/cm3 satellite III (SAT III), displaces the D1 protein. This displacement in turn results in a selective loss of HP1 and topoisomerase II from SAT III, while these proteins remain bound to the adjacent rDNA repeats and to other regions not targeted by P9. Conversely, targeting of (AAGAG)n satellite V repeats by the P31 polyamide results in the displacement of HP1 from these sequences, indicating that HP1 interactions with chromatin are sensitive to DNA-binding ligands. P9 fed to larvae suppresses the position-effect variegation phenotype of white-mottled adult flies. We propose that this effect is due to displacement of the heterochromatin proteins D1, HP1 and topoisomerase II from SAT III, hence resulting in stochastic chromatin opening and desilencing of the nearby white gene.

  4. 75 FR 34169 - Hewlett-Packard Company, Inkjet Consumer Solutions, HP Consumer Hardware Inkjet Lab, Including...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-16

    ..., engineering specifications, and drawings used in the manufacturing of HP Deskjet and Photosmart printers. New..., PDG Oncore, K Force, Supply Source, Sigma Design, Novo Engineering, Act, Stilwell Baker, and... Design, Novo Engineering, ACT, Stilwell Baker and BeyondSoft were employed on-site at the...

  5. Local rules for protein folding on a triangular lattice and generalized hydrophobicity in the HP model

    SciTech Connect

    Agarwala, R.; Batzoglou, S.; Dancik, V.

    1997-06-01

    We consider the problem of determining the three-dimensional folding of a protein given its one-dimensional amino acid sequence. We use the HP model for protein folding proposed by Dill, which models protein as a chain of amino acid residues that are either hydrophobic or polar, and hydrophobic interactions are the dominant initial driving force for the protein folding. Hart and Istrail gave approximation algorithms for folding proteins on the cubic lattice under HP model. In this paper, we examine the choice of a lattice by considering its algorithmic and geometric implications and argue that triangular lattice is a more reasonable choice. We present a set of folding rules for a triangular lattice and analyze the approximation ratio which they achieve. In addition, we introduce a generalization of the HP model to account for residues having different levels of hydrophobicity. After describing the biological foundation for this generalization, we show that in the new model we are able to achieve similar constant factor approximation guarantees on the triangular lattice as were achieved in the standard HP model. While the structures derived from our folding rules are probably still far from biological reality, we hope that having a set of folding rules with different properties will yield more interesting folds when combined.

  6. DETAIL OF GENERAL ELECTRIC 250HP SYNCHRONOUS MOTOR FROM SLIP RING ...

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

    DETAIL OF GENERAL ELECTRIC 250-HP SYNCHRONOUS MOTOR FROM SLIP RING END. NOTE BOLTS AND SPRINGS OF BRAKE BAND, HEAVY-WIRE ARMATURE WINDINGS, AND TIGHTLY WOUND STATOR (FIELD) COILS. - Shenandoah-Dives Mill, 135 County Road 2, Silverton, San Juan County, CO

  7. Citrullination of Histone H3 Interferes with HP1-Mediated Transcriptional Repression

    PubMed Central

    Sharma, Priyanka; Azebi, Saliha; England, Patrick; Christensen, Tove; Møller-Larsen, Anné; Petersen, Thor; Batsché, Eric; Muchardt, Christian

    2012-01-01

    Multiple Sclerosis (MS) is an autoimmune disease associated with abnormal expression of a subset of cytokines, resulting in inappropriate T-lymphocyte activation and uncontrolled immune response. A key issue in the field is the need to understand why these cytokines are transcriptionally activated in the patients. Here, we have examined several transcription units subject to pathological reactivation in MS, including the TNFα and IL8 cytokine genes and also several Human Endogenous RetroViruses (HERVs). We find that both the immune genes and the HERVs require the heterochromatin protein HP1α for their transcriptional repression. We further show that the Peptidylarginine Deiminase 4 (PADI4), an enzyme with a suspected role in MS, weakens the binding of HP1α to tri-methylated histone H3 lysine 9 by citrullinating histone H3 arginine 8. The resulting de-repression of both cytokines and HERVs can be reversed with the PADI-inhibitor Cl-amidine. Finally, we show that in peripheral blood mononuclear cells (PBMCs) from MS patients, the promoters of TNFα, and several HERVs share a deficit in HP1α recruitment and an augmented accumulation of histone H3 with a double citrulline 8 tri-methyl lysine 9 modifications. Thus, our study provides compelling evidence that HP1α and PADI4 are regulators of both immune genes and HERVs, and that multiple events of transcriptional reactivation in MS patients can be explained by the deficiency of a single mechanism of gene silencing. PMID:23028349

  8. Developing Consensus on the CompHP Professional Standards for Health Promotion in Europe

    ERIC Educational Resources Information Center

    Speller, Viv; Parish, Richard; Davison, Heather; Zilnyk, Anna

    2012-01-01

    Building on the CompHP Core Competencies for health promotion the Professional Standards for Health Promotion have been developed and consulted on across Europe. The standards were formulated to fit within the complexity of professional, occupational and educational standards frameworks in Europe as learning outcome standards with performance…

  9. Integration of hp-Adaptivity and a Two Grid Solver. II. Electromagnetic Problems

    DTIC Science & Technology

    2005-01-01

    for lower order FE spaces. More precisely, let T be a grid,M the associated lowest order Nedelec subspaces ofHD(curl; Ω) of the first kind [24], and W... Nedelec , Mixed finite elements in IR3., Numer. Math., 35 (1980), pp. 315–341. [25] D. Pardo and L. Demkowicz, Integration of hp-adaptivity with a two

  10. Haptoglobin (HP) and Haptoglobin-related protein (HPR) copy number variation, natural selection, and trypanosomiasis.

    PubMed

    Hardwick, Robert J; Ménard, Anne; Sironi, Manuela; Milet, Jacqueline; Garcia, André; Sese, Claude; Yang, Fengtang; Fu, Beiyuan; Courtin, David; Hollox, Edward J

    2014-01-01

    Haptoglobin, coded by the HP gene, is a plasma protein that acts as a scavenger for free heme, and haptoglobin-related protein (coded by the HPR gene) forms part of the trypanolytic factor TLF-1, together with apolipoprotein L1 (ApoL1). We analyse the polymorphic small intragenic duplication of the HP gene, with alleles Hp1 and Hp2, in 52 populations, and find no evidence for natural selection either from extended haplotype analysis or from correlation with pathogen richness matrices. Using fiber-FISH, the paralog ratio test, and array-CGH data, we also confirm that the HPR gene is copy number variable, with duplication of the whole HPR gene at polymorphic frequencies in west and central Africa, up to an allele frequency of 15 %. The geographical distribution of the HPR duplication allele overlaps the region where the pathogen causing chronic human African trypanosomiasis, Trypanosoma brucei gambiense, is endemic. The HPR duplication has occurred on one SNP haplotype, but there is no strong evidence of extended homozygosity, a characteristic of recent natural selection. The HPR duplication shows a slight, non-significant undertransmission to human African trypanosomiasis-affected children of unaffected parents in the Democratic Republic of Congo. However, taken together with alleles of APOL1, there is an overall significant undertransmission of putative protective alleles to human African trypanosomiasis-affected children.

  11. HP-9810A calculator programs for plotting the 2-dimensional motion of cyclindrical payloads relative to the shuttle orbiter

    NASA Technical Reports Server (NTRS)

    Wilson, S. W.

    1976-01-01

    The HP-9810A calculator programs described provide the capability to generate HP-9862A plotter displays which depict the apparent motion of a free-flying cyclindrical payload relative to the shuttle orbiter body axes by projecting the payload geometry into the orbiter plane of symmetry at regular time intervals.

  12. Paleomagnetism of the Mississippian HP pipe and the western margin of the North American craton

    NASA Astrophysics Data System (ADS)

    Symons, D. T. A.; Lewchuk, M. T.

    The HP pipe is a small oval (80m×40m) kimberlitic diatreme near Golden, B.C., in the fold-and-thrust belt of the Rocky Mountains. The pipe intrudes gently-dipping (˜10°S) Late Cambrian to Middle Ordovician limestones with nearly vertical contacts. It is comprised of carbonate breccia fragments and pyroxenite nodules in a light-green serpentine matrix and gives a Rb-Sr age of 348±7 Ma. A later phase of dark-green dikes cut the breccia and adjacent limestones. AF and thermal step demagnetization of 168 specimens from 42 oriented blocks was done using an automated cryogenic magnetometer in a shielded room for remanence measurement. The diatreme breccia and dikes retain a stable A remanence component after thermal cleaning above ˜400°C and AF cleaning above ˜20 mT. Their combined mean direction of 129.8°, -44.3° (α95 = 6.5°) after tilt correction gives a concordant Mississippian pole position of 138.5°E, 44.5°N (Dp = 5.1°, Dm = 8.2°). The limestones provide a positive contact test by giving a stable B component direction of 114.4°, -22.7° (α95 = 12.4°) with a concordant Late Cambrian to Middle Ordovician pole of 141.0°E, 24.3°N (δp = 7.0°, δm = 13.3°). These concordant poles indicate that the fold-and-thrust belt is part of the North American craton. Thus the suture with allochthonous terranes to the west must be located at or west of the Rocky Mountain Trench. Both the diatreme and limestones retain a low-coercivity and unblocking-temperature C component, isolated by vector subtraction without tilt correction, that records a minor overprint from the Laramide Orogeny combined with Pleistocene viscous remanence.

  13. Hp(3)/Φ conversion coefficients for neutrons: discussion on the basis of the new ICRP recommended limit for the eye lens.

    PubMed

    Ferrari, P; Gualdrini, G; Tanner, R; Fantuzzi, E

    2014-10-01

    The new recommendation issued by the International Commission on Radiological Protection (ICRP) introducing a 20-mSv annual dose limit for the eye lens stimulated an interesting debate among the radiation protection community. In the present work the problem of estimating Hp(3) for neutron realistic workplace spectra is treated, employing the recently published Hp(3)/Φ conversion coefficients with the aim of establishing a workplace-dependent relationship between Hp(10) and Hp(3). The results demonstrate that, whilst the two quantities can differ by less than 10 %, in general, Hp(10) cannot be considered a conservative estimate of Hp(3).

  14. Identification and characterization of a nuclear localization signal of TRIM28 that overlaps with the HP1 box.

    PubMed

    Moriyama, Tetsuji; Sangel, Percival; Yamaguchi, Hiroki; Obuse, Chikashi; Miyamoto, Yoichi; Oka, Masahiro; Yoneda, Yoshihiro

    2015-07-03

    Tripartite motif-containing 28 (TRIM28) is a transcription regulator, which forms a repressor complex containing heterochromatin protein 1 (HP1). Here, we report identification of a nuclear localization signal (NLS) within the 462-494 amino acid region of TRIM28 that overlaps with its HP1 binding site, HP1 box. GST-pulldown experiments revealed the interaction of the arginine-rich TRIM28 NLS with various importin α subtypes (α1, α2 and α4). In vitro transport assay demonstrated that nuclear localization of GFP-TRIM28 NLS is mediated by importin αs, in conjunction with importin β1 and Ran. Further, we demonstrated that HP1 and importin αs compete for binding to TRIM28. Together, our findings suggest that importin α has an essential role in the nuclear delivery and preferential HP1 interaction of TRIM28.

  15. Metamorphism and exhumation of the youngest known HP/UHP terrane on Earth, eastern Papua New Guinea

    NASA Astrophysics Data System (ADS)

    Baldwin, S. L.; Webb, L. E.; Monteleone, B. D.; Little, T. A.; Fitzgerald, P. G.; Chappell, J. L.

    2005-12-01

    Variably retrogressed Late Miocene-Pliocene HP/UHP rocks occur in the exhumed lower plates of the D'Entrecasteaux Islands (DI) metamorphic core complexes (mccs) in eastern Papua New Guinea (PNG). There, HP/UHP exhumation occurred in a rapidly extending (>2 cm/yr) region where the Woodlark Basin seafloor spreading system (sfs) terminates into a zone of rifting. The evolution of this complex plate boundary zone involved northward subduction of the Australian continental margin beneath oceanic lithosphere, a collision that led to HP/UHP metamorphism of Jurassic-Cretaceous sediments and basalts, and southward obduction of oceanic crust and mantle (Papuan Ultramafic Belt). P-T-t-D data reveal the variability in paths followed by rocks as they were subducted and subsequently exhumed via top-to-the-north normal-sense motion on kilometer scale mylonitic shear zones. In situ ion probe analyses on zircons and garnets yielded trace and REE patterns indicative of coeval growth under eclogite facies conditions and 206Pb/238U zircon ages ranging from 7.9-2.8 Ma. In western Fergusson Island a 7.9 Ma eclogite contains coesite, recognized petrographically as an inclusion in omphacite, and confirmed by Raman spectroscopy. Garnet - cpx - phengite barometry (~26 kbar) underestimates peak pressures required by the presence of coesite. Thermochronology (40Ar/39Ar, fission track and (U-Th)/He) on host felsic gneisses record rapid cooling during exhumation at average rates of >1 cm/yr, and indicate lower plate rocks reached shallow crustal levels by ~1.5 Ma. On Goodenough Island, in situ ion probe analyses on zircon inclusions in garnet from retrogressed eclogite lenses within host felsic gneisses yielded 206Pb/238U ages of 2.8-2.9 Ma. Zircon/garnet REE patterns support an interpretation of coeval growth at (retrograde?) HP conditions. 206Pb/238U ages for the youngest zircon population from felsic host gneisses are concordant with in situ zircon analyses from retrogressed eclogite lenses

  16. Interaction between Ni and HZSM-5 in aromatization-enhanced reactive adsorption desulfurization catalysts for FCC gasoline upgrading.

    PubMed

    Zhao, Jinchong; Zhang, Lulu; She, Nannan; Liu, Yunqi; Chai, Yongming; Liu, Chenguang

    A compound catalyst (RA) consisted of Ni, ZnO and HZSM-5 with functions of reactive adsorption desulfurization (RADS) and olefin aromatization for fluid catalytic cracking (FCC) gasoline upgrading was prepared. X-ray powder diffraction (XRD), temperature-programmed reduction and low-temperature N2 adsorption were used to characterize the properties of the catalysts. Performance evaluation by FCC gasoline was carried out, and the result showed that the catalyst RA performed well in desulfurization and aromatization. For comparison, RADS catalyst (represented by DS) consisted of Ni and ZnO and aromatization catalyst (represented by Ar) consisted of HZSM-5 were prepared, respectively. They were combined in different ways to help investigating interaction between Ni and HZSM-5. Performance evaluated by FCC gasoline showed that catalyst RA performed best in desulfurization with a slight octane number loss. Interaction between Ni and HZSM-5 is a significant factor which influences the performance of the catalyst.

  17. Evaluation of sulfur-reducing microorganisms for organic desulfurization. Final technical report, September 1, 1990--August 31, 1991

    SciTech Connect

    Miller, K.W.

    1991-12-31

    Because of substantial portion of the sulfur in Illinois coal is organic, microbial desulfurization of sulfidic and thiophenic functionalities could hold great potential for completing pyritic sulfur removal. We are testing the hypothesis that organic sulfur can be reductively removed as H{sub 2}S through the activities of anaerobic microorganisms. Our objectives for this year include the following: (1) To obtain cultures that will reductively desulfurize thiophenic model compounds. In addition to crude oil enrichments begun last year, we sampled municipal sewage sludge. (2) To continue to work toward optimizing the activity of the DBDS-reducing cultures obtained during the previous year. (3) To expand coal desulfurization work to include other coals including Illinois Basin Coal 101 and a North Dakota lignite, which might be more susceptible to the dibenzyldisulfide reducing cultures due to its lower rank. (4) To address the problem of sulfide sorption, by investigating the sorption capacity of coals in addition to Illinois Basin Coal 108.

  18. Identification and Cloning of Genes Involved in Specific Desulfurization of Dibenzothiophene by Rhodococcus sp. Strain IGTS8.

    PubMed

    Denome, S A; Olson, E S; Young, K D

    1993-09-01

    The gram-positive bacterium Rhodococcus sp. strain IGTS8 is able to remove sulfur from certain aromatic compounds without breaking carbon-carbon bonds. In particular, sulfur is removed from dibenzothiophene (DBT) to give the final product, 2-hydroxybiphenyl. A genomic library of IGTS8 was constructed in the cosmid vector pLAFR5, but no desulfurization phenotype was imparted to Escherichia coli. Therefore, IGTS8 was mutagenized, and a new strain (UV1) was selected that had lost the ability to desulfurize DBT. The genomic library was transferred into UV1, and several colonies that had regained the desulfurization phenotype were isolated, though free plasmid could not be isolated. Instead, vector DNA had integrated into either the chromosome or a large resident plasmid. DNA on either side of the inserted vector sequences was cloned and used to probe the original genomic library in E. coli. This procedure identified individual cosmid clones that, when electroporated into strain UV1, restored desulfurization. When the origin of replication from a Rhodococcus plasmid was inserted, the efficiency with which these clones transformed UV1 increased 20- to 50-fold and they could be retrieved as free plasmids. Restriction mapping and subcloning indicated that the desulfurization genes reside on a 4.0-kb DNA fragment. Finally, the phenotype was transferred to Rhodococcus fascians D188-5, a species normally incapable of desulfurizing DBT. The mutant strain, UV1, and R. fascians produced 2-hydroxybiphenyl from DBT when they contained appropriate clones, indicating that the genes for the entire pathway have been isolated.

  19. Linear dispersion-diffusion analysis and its application to under-resolved turbulence simulations using discontinuous Galerkin spectral/hp methods

    NASA Astrophysics Data System (ADS)

    Moura, R. C.; Sherwin, S. J.; Peiró, J.

    2015-10-01

    We investigate the potential of linear dispersion-diffusion analysis in providing direct guidelines for turbulence simulations through the under-resolved DNS (sometimes called implicit LES) approach via spectral/hp methods. The discontinuous Galerkin (DG) formulation is assessed in particular as a representative of these methods. We revisit the eigensolutions technique as applied to linear advection and suggest a new perspective to the role of multiple numerical modes, peculiar to spectral/hp methods. From this new perspective, "secondary" eigenmodes are seen to replicate the propagation behaviour of a "primary" mode, so that DG's propagation characteristics can be obtained directly from the dispersion-diffusion curves of the primary mode. Numerical dissipation is then appraised from these primary eigencurves and its effect over poorly-resolved scales is quantified. Within this scenario, a simple criterion is proposed to estimate DG's effective resolution in terms of the largest wavenumber it can accurately resolve in a given hp approximation space, also allowing us to present points per wavelength estimates typically used in spectral and finite difference methods. Although strictly valid for linear advection, the devised criterion is tested against (1D) Burgers turbulence and found to predict with good accuracy the beginning of the dissipation range on the energy spectra of under-resolved simulations. The analysis of these test cases through the proposed methodology clarifies why and how the DG formulation can be used for under-resolved turbulence simulations without explicit subgrid-scale modelling. In particular, when dealing with communication limited hardware which forces one to consider the performance for a fixed number of degrees of freedom, the use of higher polynomial orders along with moderately coarser meshes is shown to be the best way to translate available degrees of freedom into resolution power.

  20. Enhanced durability and reactivity for zinc ferrite desulfurization sorbent. Quarterly technical progress report No. 1, October--December 1986

    SciTech Connect

    Jha, M.C.; Baltich, L.K.

    1987-02-23

    AMAX Research & Development Center (AMAX R&D) has been investigating methods for enhancing the reactivity and durability of the zinc ferrite desulfurization sorbent. Zinc ferrite sorbents are intended for use in desulfurization of hot coal gas in integrated gasification combined cycle (IGCC) or molten carbonate fuel cell (MCFC) applications. For the present program, the reactivity of the sorbent may be defined as its sulfur sorption capacity at the breakthrough point and at saturation in a bench-scale, fixed-bed reactor. Durability may be defined as the ability of the sorbent to maintain important physical characteristics such As size, strength, and specific surface area during 10 cycles of sulfidation and oxidation.

  1. Enhanced durability and reactivity for zinc ferrite desulfurization sorbent. Volume 1, Bench-scale testing and analysis

    SciTech Connect

    Jha, M.C.; Berggren, M.H.

    1989-05-02

    AMAX Research & Development Center (AMAX R&D) has been investigating methods for enhancing the reactivity and durability of the zinc ferrite desulfurization sorbent. Zinc ferrite sorbents are intended for use in desulfurization of hot coal gas in integrated gasification combined cycle (IGCC) or molten carbonate fuel cell (MCFC) applications. For the present program, the reactivity of the sorbent may be defined as its sulfur sorption capacity at the breakthrough point and at saturation in a bench-scale, fixed-bed reactor. Durability may be defined as the ability of the sorbent to maintain important physical characteristics such As size, strength, and specific surface area during 10 cycles of sulfidation and oxidation.

  2. An efficient approach for conversion of 5-substituted 2-thiouridines built in RNA oligomers into corresponding desulfured 4-pyrimidinone products.

    PubMed

    Chwialkowska, Anna; Wielgus, Ewelina; Leszczynska, Grazyna; Sobczak, Milena; Mikolajczyk, Barbara; Sochacka, Elzbieta; Nawrot, Barbara

    2015-08-15

    An efficient approach for the desulfuration of C5-substituted 2-thiouridines (R5S2U) bound in the RNA chain exclusively to 4-pyrimidinone nucleoside (R5H2U)-containing RNA products is proposed. This post-synthetic transformation avoids the preparation of a suitably protected H2U phosphoramidite, which otherwise would be necessary for solid-phase synthesis of the modified RNA. Optimization of the desulfuration, which included reaction stoichiometry, time and temperature, allowed to transform a set of ten R5S2U-RNAs into their R5H2U-RNA congeners in ca. 90% yield.

  3. Determination of dispersion parameters for oxidizing air and the oxidation rate of calcium sulfites in a pilot desulfurization plant

    SciTech Connect

    Burenkov, D.K.; Derevich, I.V.; Rzaev, A.I.

    1995-10-01

    In the effort to remove sulfur oxides from waste gases, the widest use is gained by desulfurization plants based on wet collection of sulfur dioxide in empty absorbers in which a limestone-gypsum suspension is sprayed, with gypsum being produced as a commodity product. Dispersion of oxidizing air in a model liquid and the oxidation rate of calcium sulfites in a suspension contained in the sump of a pilot desulfurization plant absorber are studied experimentally. Flow velocities, bubble trajectories, and oxidation rates were determined and are presented.

  4. Advanced fuel gas desulfurization (AFGD) demonstration project. Technical progress report No. 19, July 1, 1994--September 30, 1994

    SciTech Connect

    1995-12-01

    The {open_quotes}Advanced Flue Gas Desulfurization (AFGD) Demonstration Project{close_quotes} is a $150.5 million cooperative effort between the U.S. Department of Energy and Pure Air, a general partnership of Air Products and Chemicals, Inc. and Mitsubishi Heavy Industries America, Inc. The AFGD process is one of several alternatives to conventional flue gas desulfurization (FGD) being demonstrated under the Department of Energy`s Clean Coal Technology Demonstration Program. The AFGD demonstration project is located at the Northern Indiana Public Service Company`s Bailly Generating Station, about 12 miles northeast of Gary, Indiana.

  5. Influence of Fe loadings on desulfurization performance of activated carbon treated by nitric acid.

    PubMed

    Guo, Jia-Xiu; Shu, Song; Liu, Xiao-Li; Wang, Xue-Jiao; Yin, Hua-Qiang; Chu, Ying-Hao

    2017-02-01

    A series of Fe supported on activated carbon treated by nitric acid are prepared by incipient wetness impregnation with ultrasonic assistance and characterized by N2 adsorption-desorption, X-ray diffraction, Fourier transform infrared spectrum and X-ray photoelectron spectroscopy. It has shown that Fe loadings significantly influence the desulfurization activity. Fe/NAC5 exhibits an excellent removal ability of SO2, corresponding to breakthrough sulfur capacity of 323 mg/g. With the increasing Fe loadings, the generated Fe3O4 and Fe2SiO4 increase, but Fe2(SO4)3 is observed after desulfurization. Fe/NAC1 has a Brunauer-Emmett-Teller (BET) surface area of 925 m(2)/g with micropore surface area of 843 m(2)/g and total pore volume of 0.562 cm(3)/g including a micropore volume of 0.300 cm(3)/g. With the increasing Fe loadings, BET surface area and micropore volume decrease, and those of Fe/NAC10 decrease to 706 m(2)/g and 0.249 cm(3)/g. The Fe loadings influence the pore-size distribution, and SO2 adsorption mainly reacts in micropores at about 0.70 nm. C=O and C-O are observed for all samples before SO2 removal. After desulfurization, the C-O stretching is still detected, but the C=O stretching vibration of carbonyl groups disappears. The stretching of S-O or S=O in sulfate is observed at 592 cm(-1) for the used sample, proving that the existence of [Formula: see text].

  6. Pilot-plant technical assessment of wet flue gas desulfurization using limestone

    SciTech Connect

    Ortiz, F.J.G.; Vidal, F.; Ollero, P.; Salvador, L.; Cortes, V.; Gimenez, A.

    2006-02-15

    An experimental study was performed on a countercurrent pilot-scale packed scrubber for wet flue gas desulfurization (FGD). The flow rate of the treated flue gas was around 300 Nm{sup 3}/h, so the pilot-plant capacity is one of the largest with respect to other published studies on a pilot-plant wet FGD. The tests were carried out at an SO{sub 2} inlet concentration of 2000 ppm by changing the recycle slurry pH to around 4.8 and the L/G ratio to between 7.5 and 15. Three types of limestone were tested, obtaining desulfurization efficiencies from 59 to 99%. We show the importance of choosing an appropriate limestone in order to get a better performance from the FGD plant. Thus, it is important to know the reactivity (on a laboratory scale) and the sorbent utilization (on a pilot-plant scale) in order to identify if a limestone is reactive enough and to compare it with another type. In addition, by using the transfer-unit concept, a function has been obtained for the desulfurization efficiency, using the L/G ratio and the recycle slurry pH as independent variables. The Ca/S molar ratio is related to these and to the SO{sub 2} removal efficiency. This function, together with a simplified function of the operation variable cost, allows us to determine the pair (L/G ratio and pH) to achieve the desired SO{sub 2} removal with the minimum operation cost. Finally, the variable operation costs between packed towers and spray scrubbers have been compared, using as a basis the pilot packed tower and the industrial spray column at the Compostilla Power Station's FGD plant (in Leon, Spain).

  7. Mass spectrometric detection of CYP450 adducts following oxidative desulfuration of methyl parathion.

    PubMed

    Kyle, Patrick B; Smith, Stanley V; Baker, Rodney C; Kramer, Robert E

    2013-07-01

    Cytochrome P450 (CYP)-mediated desulfuration of methyl parathion results in mechanism-based inhibition of the enzyme. Although previous data suggest that reactive sulfur is released and binds to the apoprotein, the identities of neither the adduct(s) nor the affected amino acid(s) have been clearly determined. In this study, nanospray tandem mass spectroscopy was used to analyze peptide digests of CYP resolved by SDS-PAGE from liver microsomes of male rats following incubation in the absence or presence of methyl parathion. Oxidative desulfuration was confirmed by measurement of methyl paraoxon, and inhibition of specific CYP isozymes was determined by measurement of testosterone hydroxylation. Total CYP content was quantified spectrophotometrically. Incubation of microsomes with methyl parathion decreased CYP content by 58%. This effect was not associated with a comparable increase in absorbance at 420 nm, suggesting the displacement of heme from the apoprotein. Rates of testosterone 2β- and 6β-hydroxylation, respectively, were reduced to 8 and 2%, implicating CYP3A and CYP2C11 in the oxidative desulfuration of methyl parathion. Mass spectrometric analysis identified 96 amu adducts to cysteines 64 and 378 of CYP3A1. In addition, a peptide containing cysteine 433 that coordinates with heme was possibly modified as it was detected in control, but not methyl parathion samples. A comparison of rat CYP3A1 with human CYP3A4 suggests that cysteines 64 and 378 reside along the substrate channel, remote from the active site. Alteration of these residues might modulate substrate entry to the binding pocket of the enzyme.

  8. Advances on simultaneous desulfurization and denitrification using activated carbon irradiated by microwaves.

    PubMed

    Ma, Shuang-Chen; Gao, Li; Ma, Jing-Xiang; Jin, Xin; Yao, Juan-Juan; Zhao, Yi

    2012-06-01

    This paper describes the research background and chemistry of desulfurization and denitrification technology using microwave irradiation. Microwave-induced catalysis combined with activated carbon adsorption and reduction can reduce nitric oxide to nitrogen and sulfur dioxide to sulfur from flue gas effectively. This paper also highlights the main drawbacks of this technology and discusses future development trends. It is reported that the removal of sulfur dioxide and nitric oxide using microwave irradiation has broad prospects for development in the field of air pollution control.

  9. Adipic acid-enhanced limestone flue gas desulfurization system commercial demonstration. [Missouri

    SciTech Connect

    Hargrove, O.W. Jr.; Colley, J.D.; Mobley, J.D.

    1981-01-01

    A full-scale demonstration carried out at Springfield, Mo City Utilities Southwest Power Plant in 1980-1981 on adipic acid enhanced limestone flue gas desulfurization system is reported. The major process findings during the demonstration are discussed. It is found that adipic acid is a viable means for improving SO/sub 2/ removal in scrubbers which are limited from a dissolved alkalinity standpoint. Dibasic acid (a mixture of glutaric, adipic, and succinic acids) is a technically viable alternative to adipic acid. 6 refs.

  10. Using stable isotopes to monitor forms of sulfur during desulfurization processes: A quick screening method

    USGS Publications Warehouse

    Liu, Chao-Li; Hackley, Keith C.; Coleman, D.D.; Kruse, C.W.

    1987-01-01

    A method using stable isotope ratio analysis to monitor the reactivity of sulfur forms in coal during thermal and chemical desulfurization processes has been developed at the Illinois State Geological Survey. The method is based upon the fact that a significant difference exists in some coals between the 34S/32S ratios of the pyritic and organic sulfur. A screening method for determining the suitability of coal samples for use in isotope ratio analysis is described. Making these special coals available from coal sample programs would assist research groups in sorting out the complex sulfur chemistry which accompanies thermal and chemical processing of high sulfur coals. ?? 1987.

  11. Process for the manufacture of an attrition resistant sorbent used for gas desulfurization

    DOEpatents

    Venkataramani, Venkat S.; Ayala, Raul E.

    2003-09-16

    This process produces a sorbent for use in desulfurization of coal gas. A zinc titanate compound and a metal oxide are mixed by milling the compounds in an aqueous medium, the resulting mixture is dried and then calcined, crushed, sleved and formed into pellets for use in a moving-bed reactor. Metal oxides suitable for use as an additive in this process include: magnesium oxide, magnesium oxide plus molybdenum oxide, calcium oxide, yttrium oxide, hafnium oxide, zirconium oxide, cupric oxide, and tin oxide. The resulting sorbent has a percentage of the original zinc or titanium ions substituted for the oxide metal of the chosen additive.

  12. Sodium-limestone double alkali flue gas desulfurization process with improved limestone utilization

    SciTech Connect

    Biolchini, R.J.; Boward, W.L. Jr.; Wang, K.H.

    1987-08-18

    This patent describes a sodium-limestone double alkali process for the continuous desulfurization of flue gas, having the steps of absorbing sulfur dioxide from an SO/sub 2/-containing gas stream in an absorber with an aqueous solution of sodium sulfite and sodium bisulfite, diverting at least a portion of the absorber effluent solution for regeneration with limestone, introducing limestone into the diverted absorber effluent solution to convert bisulfite to sulfite, separating by-product solids from the limestone-treated solution, and returning regenerated solution to the absorber, the improvement for increasing the utilization of the limestone used during the regeneration operation.

  13. Cbx3/HP1γ deficiency confers enhanced tumor-killing capacity on CD8+ T cells

    PubMed Central

    Sun, Michael; Ha, Ngoc; Pham, Duc-Hung; Frederick, Megan; Sharma, Bandana; Naruse, Chie; Asano, Masahide; Pipkin, Matthew E.; George, Rani E.; Thai, To-Ha

    2017-01-01

    Cbx3/HP1γ is a histone reader whose function in the immune system is not completely understood. Here, we demonstrate that in CD8+ T cells, Cbx3/HP1γ insufficiency leads to chromatin remodeling accompanied by enhanced Prf1, Gzmb and Ifng expression. In tumors obtained from Cbx3/HP1γ-insufficient mice or wild type mice treated with Cbx3/HP1γ-insufficient CD8+ T cells, there is an increase of CD8+ effector T cells expressing the stimulatory receptor Klrk1/NKG2D, a decrease in CD4+ CD25+ FOXP3+ regulatory T cells (Treg cells) as well as CD25+ CD4+ T cells expressing the inhibitory receptor CTLA4. Together these changes in the tumor immune environment may have mitigated tumor burden in Cbx3/HP1γ-insufficient mice or wild type mice treated with Cbx3/HP1γ-insufficient CD8+ T cells. These findings suggest that targeting Cbx3/HP1γ can represent a rational therapeutic approach to control growth of solid tumors. PMID:28220815

  14. Heterochromatin-associated interactions of Drosophila HP1a with dADD1, HIPP1, and repetitive RNAs.

    PubMed

    Alekseyenko, Artyom A; Gorchakov, Andrey A; Zee, Barry M; Fuchs, Stephen M; Kharchenko, Peter V; Kuroda, Mitzi I

    2014-07-01

    Heterochromatin protein 1 (HP1a) has conserved roles in gene silencing and heterochromatin and is also implicated in transcription, DNA replication, and repair. Here we identify chromatin-associated protein and RNA interactions of HP1a by BioTAP-XL mass spectrometry and sequencing from Drosophila S2 cells, embryos, larvae, and adults. Our results reveal an extensive list of known and novel HP1a-interacting proteins, of which we selected three for validation. A strong novel interactor, dADD1 (Drosophila ADD1) (CG8290), is highly enriched in heterochromatin, harbors an ADD domain similar to human ATRX, displays selective binding to H3K9me2 and H3K9me3, and is a classic genetic suppressor of position-effect variegation. Unexpectedly, a second hit, HIPP1 (HP1 and insulator partner protein-1) (CG3680), is strongly connected to CP190-related complexes localized at putative insulator sequences throughout the genome in addition to its colocalization with HP1a in heterochromatin. A third interactor, the histone methyltransferase MES-4, is also enriched in heterochromatin. In addition to these protein-protein interactions, we found that HP1a selectively associated with a broad set of RNAs transcribed from repetitive regions. We propose that this rich network of previously undiscovered interactions will define how HP1a complexes perform their diverse functions in cells and developing organisms.

  15. Development of a novel viral DNA vaccine against human papillomavirus: AcHERV-HP16L1.

    PubMed

    Lee, Hee-Jung; Park, Nuri; Cho, Hee-Jeong; Yoon, Jong Kwang; Van, Nguyen Dinh; Oh, Yu-Kyoung; Kim, Young Bong

    2010-02-10

    In this study, we developed a novel DNA vaccine for HPV; a recombinant baculovirus bearing human endogenous retrovirus (HERV) envelope protein, which cannot replicate in mammals, was used as a nano-carrier for HPV-16L1 DNA vaccine (AcHERV-HP16L1). For in vivo test, mice were injected intramuscularly with 107 particles of the constructs, with two boosts at 2-week intervals. Compared with Gardasil (25 microL/dose), the AcHERV-HP16L1 immunized mice showed similar high levels of humoral immunity in IgG/IgA and in neutralization of HPV pseudovirions. Combined immunization (prime with AcHERV-HP16L1 and boost with Gardasil) induced slightly higher neutralizing activity. As compared to the group treated with Gardasil, the mice immunized with AcHERV-HP16L1 showed 450- and 490-fold increase in the IFN-gamma at 5 and 20 weeks after the first priming, respectively. The combined immunization conferred lower T cell immunity than AcHERV-HP16L1 treatment. The advantages of our novel AcHERV-HP16L1 vaccine over Gardasil include higher cellular immunogenicity, considerably lower production cost, and comparable safety. Therefore, we suggest that AcHERV-HP16L1 can be developed as an efficient prophylactic vaccine and therapeutic vaccine.

  16. Identification and characterization of a nuclear localization signal of TRIM28 that overlaps with the HP1 box

    SciTech Connect

    Moriyama, Tetsuji; Sangel, Percival; Yamaguchi, Hiroki; Obuse, Chikashi; Miyamoto, Yoichi; Oka, Masahiro; Yoneda, Yoshihiro

    2015-07-03

    Tripartite motif-containing 28 (TRIM28) is a transcription regulator, which forms a repressor complex containing heterochromatin protein 1 (HP1). Here, we report identification of a nuclear localization signal (NLS) within the 462-494 amino acid region of TRIM28 that overlaps with its HP1 binding site, HP1 box. GST-pulldown experiments revealed the interaction of the arginine-rich TRIM28 NLS with various importin α subtypes (α1, α2 and α4). In vitro transport assay demonstrated that nuclear localization of GFP-TRIM28 NLS is mediated by importin αs, in conjunction with importin β1 and Ran. Further, we demonstrated that HP1 and importin αs compete for binding to TRIM28. Together, our findings suggest that importin α has an essential role in the nuclear delivery and preferential HP1 interaction of TRIM28. - Highlights: • TRIM28 contains an NLS within the 462-494 amino acid region. • The nuclear import of TRIM28 is mediated by importin α/importin β1. • TRIM28 NLS overlaps with HP1 Box. • HP1 and importin α compete for binding to TRIM28.

  17. Periodic trim solutions with hp-version finite elements in time

    NASA Technical Reports Server (NTRS)

    Peters, David A.; Hou, Lin-Jun

    1990-01-01

    Finite elements in time as an alternative strategy for rotorcraft trim problems are studied. The research treats linear flap and linearized flap-lag response both for quasi-trim and trim cases. The connection between Fourier series analysis and hp-finite elements for periodic a problem is also examined. It is proved that Fourier series is a special case of space-time finite elements in which one element is used with a strong displacement formulation. Comparisons are made with respect to accuracy among Fourier analysis, displacement methods, and mixed methods over a variety parameters. The hp trade-off is studied for the periodic trim problem to provide an optimum step size and order of polynomial for a given error criteria. It is found that finite elements in time can outperform Fourier analysis for periodic problems, and for some given error criteria. The mixed method provides better results than does the displacement method.

  18. Surface adsorption of lattice HP proteins: Thermodynamics and structural transitions using Wang-Landau sampling

    NASA Astrophysics Data System (ADS)

    Li, Ying Wai; Wüst, Thomas; Landau, David P.

    2012-12-01

    Wang-Landau sampling has been applied to investigate the thermodynamics and structural properties of a lattice hydrophobic-polar heteropolymer (the HP protein model) interacting with an attractive substrate. For simplicity, we consider a short HP sequence consisting of only 36 monomers interacting with a substrate which attracts all monomers in the sequence. The conformational “phase transitions” have been identified by a canonical analysis of the specific heat and suitable structural observables. Three major “transitions”, namely, adsorption, hydrophobic core formation and “flattening” of adsorbed structures, are observed. Depending on the surface attractive strength relative to the intra-protein attraction among the H monomers, these processes take place in different sequences upon cooling.

  19. Wang-Landau sampling of protein adsorption using the HP model

    NASA Astrophysics Data System (ADS)

    Li, Ying-Wai; Landau, D. P.; Wuest, T.

    2011-03-01

    We have applied Wang-Landau sampling with appropriate trial moves to investigate the thermodynamics and structural properties of lattice hydrophobic-polar heteropolymers (commonly known as the HP protein model) interacting with an attractive substrate. We estimate the density of states of the system, from which the partition function and all thermodynamic quantities, e.g. specific heat, radius of gyration, end-to-end distance and surface contacts, can be calculated. ``Transitions'' between ``phases'' are then identified based on a comprehensive analysis of these observables. Generally speaking, three transition processes are observed: adsorption-desorption, collapse (formation of hydrophobic core), and ``flattening'' of adsorbed structures. These have been confirmed by ``snapshots'' of typical states of the system. Depending on the surface attractive strength, these transitions take place in different order upon cooling, giving rise to different thermodynamic behaviors. Such dependence of folding hierarchy on the surface attraction is found to be universal for different HP sequences. Research supported by NSF.

  20. Approach to hp10nm resolution by applying Dry Development Rinse Process (DDRP) and Materials (DDRM)

    NASA Astrophysics Data System (ADS)

    Shibayama, Wataru; Shigaki, Shuhei; Takeda, Satoshi; Onishi, Ryuji; Nakajima, Makoto; Sakamoto, Rikimaru

    2016-03-01

    EUV lithography has been desired as the leading technology for single nm half-pitch patterning. However, the source power, masks and resist materials still have critical issues for mass production. Especially in resist materials, RLS trade-off is the key issue. To overcome this issue, we are suggesting Dry Development Rinse Process (DDRP) and Materials (DDRM) as the pattern collapse mitigation approach. This DDRM can perform not only as pattern collapse free materials for fine pitch, but also as the etching hard mask against bottom layer (spin on carbon : SOC). In this paper, we especially propose new approaches to achieve high resolution around hp10nm. The key points of our concepts are 1) control PR profiles, 2) new solvent system to avoid chemical mixture, 3) high etching selective DDR materilas and 4) high planar DDR materials. This new DDRM technology can be the promising approach for hp10nm level patterning in N7/N5 and beyond.

  1. Fuzzy physical programming for Space Manoeuvre Vehicles trajectory optimization based on hp-adaptive pseudospectral method

    NASA Astrophysics Data System (ADS)

    Chai, Runqi; Savvaris, Al; Tsourdos, Antonios

    2016-06-01

    In this paper, a fuzzy physical programming (FPP) method has been introduced for solving multi-objective Space Manoeuvre Vehicles (SMV) skip trajectory optimization problem based on hp-adaptive pseudospectral methods. The dynamic model of SMV is elaborated and then, by employing hp-adaptive pseudospectral methods, the problem has been transformed to nonlinear programming (NLP) problem. According to the mission requirements, the solutions were calculated for each single-objective scenario. To get a compromised solution for each target, the fuzzy physical programming (FPP) model is proposed. The preference function is established with considering the fuzzy factor of the system such that a proper compromised trajectory can be acquired. In addition, the NSGA-II is tested to obtain the Pareto-optimal solution set and verify the Pareto optimality of the FPP solution. Simulation results indicate that the proposed method is effective and feasible in terms of dealing with the multi-objective skip trajectory optimization for the SMV.

  2. Characterization of welded HP 9-4-30 steel for the advanced solid rocket motor

    NASA Technical Reports Server (NTRS)

    Watt, George William

    1990-01-01

    Solid rocket motor case materials must be high-strength, high-toughness, weldable alloys. The Advanced Solid Rocket Motor (ASRM) cases currently being developed will be made from a 9Ni-4Co quench and temper steel called HP 9-4-30. These ultra high-strength steels must be carefully processed to give a very clean material and a fine grained microstructure, which insures excellent ductility and toughness. The HP 9-4-30 steels are vacuum arc remelted and carbon deoxidized to give the cleanliness required. The ASRM case material will be formed into rings and then welded together to form the case segments. Welding is the desired joining technique because it results in a lower weight than other joining techniques. The mechanical and corrosion properties of the weld region material were fully studied.

  3. An hp-adaptivity and error estimation for hyperbolic conservation laws

    NASA Technical Reports Server (NTRS)

    Bey, Kim S.

    1995-01-01

    This paper presents an hp-adaptive discontinuous Galerkin method for linear hyperbolic conservation laws. A priori and a posteriori error estimates are derived in mesh-dependent norms which reflect the dependence of the approximate solution on the element size (h) and the degree (p) of the local polynomial approximation. The a posteriori error estimate, based on the element residual method, provides bounds on the actual global error in the approximate solution. The adaptive strategy is designed to deliver an approximate solution with the specified level of error in three steps. The a posteriori estimate is used to assess the accuracy of a given approximate solution and the a priori estimate is used to predict the mesh refinements and polynomial enrichment needed to deliver the desired solution. Numerical examples demonstrate the reliability of the a posteriori error estimates and the effectiveness of the hp-adaptive strategy.

  4. Development of an hp-version finite element method for computational optimal control

    NASA Technical Reports Server (NTRS)

    Hodges, Dewey H.; Warner, Michael S.

    1993-01-01

    The purpose of this research effort is to develop a means to use, and to ultimately implement, hp-version finite elements in the numerical solution of optimal control problems. The hybrid MACSYMA/FORTRAN code GENCODE was developed which utilized h-version finite elements to successfully approximate solutions to a wide class of optimal control problems. In that code the means for improvement of the solution was the refinement of the time-discretization mesh. With the extension to hp-version finite elements, the degrees of freedom include both nodal values and extra interior values associated with the unknown states, co-states, and controls, the number of which depends on the order of the shape functions in each element.

  5. Periodic trim solutions with hp-version finite elements in time

    NASA Technical Reports Server (NTRS)

    Hou, Lin-Jun; Peters, David A.

    1991-01-01

    Finite elements in time as an alternative strategy for rotorcraft trim problems are studied. The research treats linear flap and linearized flap-lag response both for quasi-trim and trim cases. The connection between Fourier series analysis and hp-finite elements for periodic a problem is also examined. It is proved that Fourier series is a special case of space-time finite elements in which one element is used with a strong displacement formulation. Comparisons are made with respect to accuracy among Fourier analysis, displacement methods, and mixed methods over a variety parameters. The hp trade-off is studied for the periodic trim problem to provide an optimum step size and order of polynomial for a given error criteria. It is found that finite elements in time can outperform Fourier analysis for periodic problems, and for some given error criteria. The mixed method provides better results than does the displacement method.

  6. HP-MoO2: A High-Pressure Polymorph of Molybdenum Dioxide.

    PubMed

    Lüdtke, Tobias; Wiedemann, Dennis; Efthimiopoulos, Ilias; Becker, Nils; Seidel, Stefan; Janka, Oliver; Pöttgen, Rainer; Dronskowski, Richard; Koch-Müller, Monika; Lerch, Martin

    2017-02-20

    High-pressure molybdenum dioxide (HP-MoO2) was synthesized using a multianvil press at 18 GPa and 1073 K, as motivated by previous first-principles calculations. The crystal structure was determined by single-crystal X-ray diffraction. The new polymorph crystallizes isotypically to HP-WO2 in the orthorhombic crystal system in space group Pnma and was found to be diamagnetic. Theoretical investigations using structure optimization at density-functional theory (DFT) level indicate a transition pressure of 5 GPa at 0 K and identify the new compound as slightly metastable at ambient pressure with respect to the thermodynamically stable monoclinic MoO2 (α-MoO2; ΔEm = 2.2 kJ·mol(-1)).

  7. Crystal structure of the secreted protein HP1454 from the human pathogen Helicobacter pylori.

    PubMed

    Quarantini, Sandra; Cendron, Laura; Zanotti, Giuseppe

    2014-10-01

    HP1454 is a protein of 303 amino acids found in the extracellular milieu of Helicobacter pylori. The protein structure, crystallized in the orthorhombic C222₁ space group with one molecule per asymmetric unit, has been determined using the single-wavelength anomalous dispersion method. HP1454 exhibits an elongated bent shape, composed of three distinct domains. Each domain possesses a fold already present in other structures: Domain I contains a three-strand antiparallel β-barrel flanked by a long α-helix, Domain II is an anti-parallel three-helix bundle, and Domain III a β-sheet flanked by two α-helices. The overall assembly of the protein does not bear any similarity with known structures.

  8. Conceptual design of 500 to 3000 hp Stirling engines for stationary power generation

    NASA Astrophysics Data System (ADS)

    Toscano, W. M.; Chandrasehkar, R.; Harvey, A. C.; Lee, K.

    Both near term and far term conceptual designs of a 373 kW (500 hp) to 2237 kW (3000 hp) Stirling engine for stationary power generation have been prepared. The recommended near term conceptual design is modular, consisting of a basic Stirling engine cylinder of 100 kW that is easily adaptable to any type of heat input or machine output. The engine output configuration selected is the single crank, narrow V, multicylinder arrangement in which any number of cylinders, in groups of four or five, provide the desired power rating. For clean fuel combustion, the prevaporized, premixed, combustion method with exhaust gas recirculation is employed. For coal combustion a Wormser Grate two-stage atmospheric fluidized bed combustion system with a high pressure gas circulation loop system is recommended. The predicted overall fuel to electrical energy conversion efficiency varied between 25 and 34 percent, depending on the system configuration.

  9. Efficiency transfer in the calibration of a coaxial p-type HpGe detector using the Monte Carlo method.

    PubMed

    Vargas, M Jurado; Díaz, N Cornejo; Sánchez, D Pérez

    2003-06-01

    Monte Carlo simulation was applied to the efficiency transfer exercise described in the EUROMET428 project (Appl. Radiat. Isot. 55 (2001) 493), evaluating the peak efficiencies in the energy range 60-2000 keV for a typical coaxial p-type HpGe detector and several types of source configuration: point sources located at various distances from the detector and a cylindrical box containing three matrices. The efficiency values were derived in two ways: (a) by direct calculation taking into account the physical dimensions of the detector provided by the supplier, and (b) by means of relative computation (efficiency transfer) taking also into consideration the known efficiency values for a reference point source. As expected, some significant discrepancies between the calculated and experimental values were found when a direct computation was made using the data provided by the supplier. On the contrary, the results for the peak efficiency derived by relative calculation by means of an efficiency transfer were in good agreement with the experimental values. The deviations found with this last procedure were generally below 5% for all the geometries considered, which is entirely satisfactory for the purposes of routine measurements.

  10. Improvement of pulmonary absorption of poorly absorbable macromolecules by hydroxypropyl-β-cyclodextrin grafted polyethylenimine (HP-β-CD-PEI) in rats.

    PubMed

    Zhang, Hailong; Huang, Xiaoyan; Sun, Ya; Lu, Guangyou; Wang, Ke; Wang, Zhigang; Xing, Jianfeng; Gao, Yang

    2015-07-15

    Effects of hydroxypropyl-β-cyclodextrin grafted polyethylenimine (HP-β-CD-PEI) including HP-β-CD-PEI600, HP-β-CD-PEI1800, HP-β-CD-PEI10000 on the pulmonary absorption of insulin, calcitonin, 5(6)-carboxyfluorescein (CF) and fluorescein isothiocyanate dextrans (FDs) with various molecular weights (FD4, FD10 and FD70) were examined by an pulmonary absorption study in rats. Pulmonary absorptions of these poorly absorbable drugs were significantly enhanced by HP-β-CD-PEI1800 and HP-β-CD-PEI10000, and HP-β-CD-PEI1800 with the concentration of 5% (w/v) provided maximal absorption enhancing effect on pulmonary absorption of these model drugs. The toxicity study demonstrated that HP-β-CD-PEI did not induce any toxic action to rat pulmonary membranes. In addition, zeta potential of insulin solution changed to positive by addition of various HP-β-CD-PEI, meanwhile, the degree of positive charge was linearly correlated with absorption enhancing effect of HP-β-CD-PEI, suggesting that positive charge of HP-β-CD-PEI might be related to their absorption enhancing mechanisms for enhancing pulmonary absorption of insulin in rats. In conclusion, HP-β-CD-PEI is a potential and safe absorption enhancer for improving absorption of hydrophilic macromolecules especially peptide and protein drugs by pulmonary delivery.

  11. Recent Progress in the p and h-p Version of the Finite Element Method.

    DTIC Science & Technology

    1987-07-01

    THE p AND h-p VERSION OF THE FINITE ELDIEr METHOD I. Babu~ka Institute tor Physical Science and Technology University of Maryland, College Park, MD...85-K-0169 9. PERFORMING ORGANIZATION NAME ANO ADDRESS 1* -PROGRAM ELEMENT. PROJECT . T ASK AREA & WORK UNIT NUMBE RS University of Maryland Institute ...METHOD by I. Babu~ka Institute for Physical Science and Technology University of Maryland, College Park, MD 20742 1. INTRODUCTION finite element method

  12. The h-p Version of the Finite Element Method with Quasiuniform Meshes.

    DTIC Science & Technology

    1986-05-01

    Noetic Technologies, St. Louis).1 The theoretical aspects have been studied only recently. The first theoretical paper appeared in 1981 (see [6...Research Reports :~ :~THE h-p VERSION OF THE FINITE ELEMENT METHOD WITH QUASIUNIFORM MESHES I. Babuska Institute for Physical Science and Technology...p VERSION OF THE FINITE ELEMENT METHOD > ’ WITH QUASIUNIFORM MESHES t. Ba bus aka1 Institute for Physical Science and Technology University of

  13. 5. INDUSTRIAL PIPING SYSTEM FOR 500 H.P. LLEWELLYN BOILER, ADDITION ...

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

    5. INDUSTRIAL PIPING SYSTEM FOR 500 H.P. LLEWELLYN BOILER, ADDITION TO POWER HOUSE. United Engineering Company Ltd., Alameda Shipyard. John Hudspeth, architect, foot of Main Street, Alameda, California. Sheet M1. Plan no. 10,551. Scale 1/4 inch to the foot. June 1, 1945. pencil on vellum - United Engineering Company Shipyard, Boiler House, 2900 Main Street, Alameda, Alameda County, CA

  14. Looking-Free Mixed hp Finite Element Methods for Linear and Geometrically Nonlinear Elasticity

    DTIC Science & Technology

    1997-06-09

    element method. Particu- lar areas of interest : hp versions, mixed methods , nearly incompressible materials, curvilinear domains, nonlinear elasticity...1 Introduction 1 2 Preliminaries 10 2.1 The Standard and Mixed Methods for Linear Elasticity .......... 10 2.2 Locking...be used to denote pressure, we use k to denote polynomial degree. 4 Mixed methods have also been used to avoid locking. In these methods, an aux

  15. A conformational switch in HP1 releases auto-inhibition to drive heterochromatin assembly

    PubMed Central

    Canzio, Daniele; Liao, Maofu; Naber, Nariman; Pate, Ed; Larson, Adam; Wu, Shenping; Marina, Diana B.; Garcia, Jennifer F.; Madhani, Hiten D.; Cooke, Roger; Schuck, Peter; Cheng, Yifan; Narlikar, Geeta J.

    2014-01-01

    A hallmark of histone H3 lysine 9 (H3K9) methylated heterochromatin, conserved from fission yeast,Schizosaccharomyces pombe (S. pombe), to humans, is its ability to spread to adjacent genomic regions1–6. Central to heterochromatin spread is the heterochromatin protein 1 (HP1), which recognizes H3K9 methylated chromatin, oligomerizes, and forms a versatile platform that participates in diverse nuclear functions, ranging from gene silencing to chromosome segregation1–6. How HP1 proteins assemble on methylated nucleosomal templates and how the HP1-nucleosome complex achieves functional versatility remain poorly understood. Here, we show that binding of the major S. pombe HP1 protein, Swi6, to methylated nucleosomes drives a switch from an auto-inhibited state to a spreading competent state. In the auto-inhibited state, a histone mimic sequence in one Swi6 monomer blocks methyl mark recognition by the chromodomain of another monomer. Auto-inhibition is relieved by recognition of two template features, the H3K9 methyl mark and nucleosomal DNA. Cryo-Electron Microscopy (EM) based reconstruction of the Swi6-nucleosome complex provides the overall architecture of the spreading-competent state in which two unbound chromodomain sticky ends appear exposed. Disruption of the switch between the auto-inhibited and spreading competent state disrupts heterochromatin assembly and gene silencing in vivo. These findings are reminiscent of other conditionally activated polymerization processes, such as actin nucleation, and open up a new class of regulatory mechanisms that operate on chromatin in vivo. PMID:23485968

  16. Detailed description of the HP-9825A HFRMP trajectory processor (TRAJ)

    NASA Technical Reports Server (NTRS)

    Kindall, S. M.; Wilson, S. W.

    1979-01-01

    The computer code for the trajectory processor of the HP-9825A High Fidelity Relative Motion Program is described in detail. The processor is a 12-degrees-of-freedom trajectory integrator which can be used to generate digital and graphical data describing the relative motion of the Space Shuttle Orbiter and a free-flying cylindrical payload. Coding standards and flow charts are given and the computational logic is discussed.

  17. An h-p Taylor-Galerkin finite element method for compressible Euler equations

    NASA Technical Reports Server (NTRS)

    Demkowicz, L.; Oden, J. T.; Rachowicz, W.; Hardy, O.

    1991-01-01

    An extension of the familiar Taylor-Galerkin method to arbitrary h-p spatial approximations is proposed. Boundary conditions are analyzed, and a linear stability result for arbitrary meshes is given, showing the unconditional stability for the parameter of implicitness alpha not less than 0.5. The wedge and blunt body problems are solved with both linear, quadratic, and cubic elements and h-adaptivity, showing the feasibility of higher orders of approximation for problems with shocks.

  18. Examination results of the Three Mile Island radiation detector HP-R-212

    SciTech Connect

    Mueller, G M

    1984-01-01

    Area radiation detector HP-R-212 was removed from the Three Mile Island containment building on November 13, 1981. The detector apparently started to fail during November 1979 and by the first part of December 1979 the detector readings had degraded from 1 R/h to 20 mR/h. This report discusses the cause of ailure, detector radiation measurement characteristics, and our estimates of the total gamma radiation dose received by the detector electronics.

  19. TST from geofinder traverse data on HP41CV programmable calculator

    SciTech Connect

    Carman, G.J. )

    1989-02-01

    Using program subroutines designed for the HP41CV programmable calculator and the geometric data recorded from Geofinder traversing or other pace-and-compass-type methods, the true stratigraphic thickness (TST) of dipping or gently folded strata is calculated at a rate of about 30 seconds per station. TST information is therefore readily available for reviewing stratigraphic and structure data and for post survey graphical plots.

  20. Generic transition hierarchies of lattice HP protein adsorption: A Wang-Landau study

    NASA Astrophysics Data System (ADS)

    Li, Ying Wai; Landau, D. P.; Wüst, T.

    2012-02-01

    We have applied Wang-Landau sampling with appropriate trial movesootnotetextT. W"ust and D. P. Landau, Phy. Rev. Lett. 102, 178101 (2009). to investigate the thermodynamics and structural properties of the HP lattice protein modelootnotetextK. A. Dill, Biochemistry 24, 1501 (1985). interacting with an attractive substrate. The conformational ``phase transitions'' of several benchmark HP sequences have been identified by a comprehensive canonical analysis of the specific heat and structural observables, e. g. radius of gyration and thermal derivatives of number of surface contacts. Three major ``transitions'': adsorption, hydrophobic core formation, and ``flattening'' of adsorbed structures, are observed. Depending on the surface attractive strength relative to the intra-protein attraction among the H monomers, these processes take place in a different order upon cooling. We identify a small number of generic categories that are sufficient to classify the folding hierarchies for different HP chains consisting of assorted sequences and chain lengths, regardless of the monomer type that the surface attracts. We thus believe that this classification scheme is generally applicable to lattice protein adsorption problems.

  1. Wang-Landau sampling of the interplay between surface adsorption and folding of HP lattice proteins

    SciTech Connect

    Li, Ying Wai; Wuest, Thomas; Landau, David P

    2014-01-01

    Generic features associated with the adsorption of proteins on solid surfaces are reviewed within the framework of the hydrophobic-polar (HP) lattice protein model. The thermodynamic behavior and structural properties of various HP protein sequences interacting with attractive surfaces have been studied using extensive Wang-Landau sampling with different types of surfaces, each of which attracts either: all monomers, only hydrophobic (H) monomers, or only polar (P) monomers, respectively. Consequently, different types of folding behavior occur for varied surface strengths. Analysis of the combined patterns of various structural observables, e.g., the derivatives of the numbers of interaction contacts, together with the specific heat, leads to the identification of fundamental categories of folding and transition hierarchies. We also inferred a connection between the transition categories and the relative surface strengths, i.e., the ratios of the surface attractive strengths to the intra-chain attraction among H monomers. We thus believe that the folding hierarchies and identification scheme are generic for different HP sequences interacting with attractive surfaces, regardless of the chain length, sequence, or surface attraction.

  2. Microstructural characterization of dissimilar welds between alloy 800 and HP heat-resistant steel

    SciTech Connect

    Dehmolaei, R.; Shamanian, M. Kermanpur, A.

    2008-10-15

    In this study, dissimilar welds between HP heat-resistant steel and Incoloy 800 were made with four different filler materials including: 309 stainless steel and nickel-based Inconel 82, 182 and 617. The microstructure of the base metals, weld metals and their interfaces were characterized by utilizing optical and scanning electron microscopy. Grain boundaries migration in the weld metals was studied. It was found that the migration of grain boundaries in the Inconel 82 weld metal was very extensive. Precipitates of TiC and M{sub 23}C{sub 6} (M = Cr and Mo) in the Inconel 617 weld metal are identified. The necessary conditions for the formation of cracks close to the fusion line of the 309-HP joints are described. Furthermore unmixed zone near the fusion line between HP steel base metal and Inconel 82 weld metal is discussed. An epitaxial growth is characterized at the fusion line of the 309-Alloy 800 and Inconel 617-Alloy 800 joints.

  3. HP-Xe to go: Storage and transportation of hyperpolarized 129Xenon

    NASA Astrophysics Data System (ADS)

    Repetto, M.; Zimmer, S.; Allmendinger, F.; Blümler, P.; Doll, M.; Grasdijk, J. O.; Heil, W.; Jungmann, K.; Karpuk, S.; Krause, H.-J.; Offenhäusser, A.; Schmidt, U.; Sobolev, Y.; Willmann, L.

    2016-04-01

    Recently the spin-lattice relaxation time T1 of hyperpolarized (HP)-129Xe was significantly improved by using uncoated and Rb-free storage vessels of GE180 glass. For these cells, a simple procedure was established to obtain reproducible wall relaxation times of about 18 h. Then the limiting relaxation mechanism in pure Xe is due to the coupling between the nuclear spins and the angular momentum of the Xe-Xe van-der-Waals-molecules. This mechanism can be significantly reduced by using different buffer gases of which CO2 was discovered to be the most efficient so far. From these values, it was estimated that for a 1:1 mixture of HP-Xe with CO2 a longitudinal relaxation time of about 7 h can be expected, sufficient to transport HP-Xe from a production to a remote application site. This prediction was verified for such a mixture at a total pressure of about 1 bar in a 10 cm glass cell showing a storage time of T1 ≈ 9 h (for T1wall = (34 ± 9) h) which was transported inside a magnetic box over a distance of about 200 km by car.

  4. Nighttime thermospheric meridional winds inferred from ionospheric h-F and hpF2 data

    NASA Astrophysics Data System (ADS)

    Muella, M. T. A. H.; Fagundes, P. R.; Bittencourt, J. A.; Sahai, Y.; Lima, W. L. C.; Becker-Guedes, F.; Pillat, V. G.

    Nighttime thermospheric meridional winds along the magnetic meridian have been inferred using ionospheric parameters h F and hpF2 obtained at two equatorial stations Manaus 2 9 o S 60 0 o W dip latitude 6 4 o N and Palmas 10 2 o S 48 o W dip latitude5 5 o S and one low latitude station S a o Jos e dos Campos 23 2 o S 45 9 o W dip latitude 17 6 o S during geomagnetically quiet periods in the months of August and September 2002 The height variations of the parameters h F and hpF2 were obtained by three digital ionosondes of the type known as the Canadian Advanced Digital Ionosonde CADI which are operated in time-synchronized mode and takes ionograms every 5 minutes An extension of the servo model is applied in order to infer the magnetic meridional component of the thermospheric neutral winds over the low latitude region The coefficients of diffusion recombination and loss rate required in the servo equations were calculated using an appropriated atmospheric model MSIS-90 In this work we show that the servo model gives similar results using either h F or hpF2 This result is interesting because it shows that during the months of August and September the wind systems are similar at both bottomside and peak of the F-layer

  5. Characterization and cloning of oxygen-tolerant hydrogenase from Klebsiella oxytoca HP1.

    PubMed

    Wu, Xiaobing; Liang, Yi; Li, Qianyi; Zhou, Juan; Long, Minnan

    2011-04-01

    Hydrogenase from a hot spring bacterium Klebsiella oxytoca HP1 was purified and found to have a specific activity of 199.8 U/mg of protein and a yield of 7.3%. The purified enzyme was determined to consist of six subunits (65, 33, 28, 23, 21 and 18 kDa), similar to hydrogenase-3 from Escherichia coli, and therefore it was named Hyd3. The enzyme displayed remarkable oxygen tolerance. For the purified enzyme, 50% maximal activity was maintained following incubation for 24 h in air at room temperature. The hydrogenase gene cluster (hyc) was cloned and found to consist of hycD, hycE, hycF, hycdG, hycH and hycI genes. hycE and hycG genes encode for the large and small subunit of the hydrogenase, respectively. A hycE gene deletion mutant, ΔhycE, was constructed for elucidating the function of the hyc-operon in hydrogen metabolism. Compared with the wild type strain HP1, the mutant strain showed a dramatic decrease in hydrogen production in the presence of formate, sodium pyruvate and glucose under O(2)-stressed conditions, while substantial activity was detected under anaerobic conditions. This strongly suggests that K. oxytoca HP1 carries a number of hydrogenases or hydrogen metabolic pathways independently of Hyd3. However, Hyd3 is the main factor responsible for hydrogen production under O(2) stress conditions.

  6. Enhanced hybrid search algorithm for protein structure prediction using the 3D-HP lattice model.

    PubMed

    Zhou, Changjun; Hou, Caixia; Zhang, Qiang; Wei, Xiaopeng

    2013-09-01

    The problem of protein structure prediction in the hydrophobic-polar (HP) lattice model is the prediction of protein tertiary structure. This problem is usually referred to as the protein folding problem. This paper presents a method for the application of an enhanced hybrid search algorithm to the problem of protein folding prediction, using the three dimensional (3D) HP lattice model. The enhanced hybrid search algorithm is a combination of the particle swarm optimizer (PSO) and tabu search (TS) algorithms. Since the PSO algorithm entraps local minimum in later evolution extremely easily, we combined PSO with the TS algorithm, which has properties of global optimization. Since the technologies of crossover and mutation are applied many times to PSO and TS algorithms, so enhanced hybrid search algorithm is called the MCMPSO-TS (multiple crossover and mutation PSO-TS) algorithm. Experimental results show that the MCMPSO-TS algorithm can find the best solutions so far for the listed benchmarks, which will help comparison with any future paper approach. Moreover, real protein sequences and Fibonacci sequences are verified in the 3D HP lattice model for the first time. Compared with the previous evolutionary algorithms, the new hybrid search algorithm is novel, and can be used effectively to predict 3D protein folding structure. With continuous development and changes in amino acids sequences, the new algorithm will also make a contribution to the study of new protein sequences.

  7. Novel preparation of PLGA/HP55 nanoparticles for oral insulin delivery

    NASA Astrophysics Data System (ADS)

    Wu, Zhi Min; Ling, Li; Zhou, Li Ying; Guo, Xin Dong; Jiang, Wei; Qian, Yu; Luo, Kathy Qian; Zhang, Li Juan

    2012-06-01

    The aim of the present study was to develop the PLGA/HP55 nanoparticles with improved hypoglycemic effect for oral insulin delivery. The insulin-loaded PLGA/HP55 nanoparticles were produced by a modified multiple emulsion solvent evaporation method. The physicochemical characteristics, in vitro release of insulin, and in vivo efficacy in diabetic rats of the nanoparticles were evaluated. The insulin encapsulation efficiency was up to 94%, and insulin was released in a pH-dependent manner under simulated gastrointestinal conditions. When administered orally (50 IU/kg) to diabetic rats, the nanoparticles can decrease rapidly the blood glucose level with a maximal effect between 1 and 8 h. The relative bioavailability compared with subcutaneous injection (5 IU/kg) in diabetic rats was 11.3% ± 1.05%. This effect may be explained by the fast release of insulin in the upper intestine, where it is better absorbed by the high gradient concentration of insulin than other regions. These results show that the PLGA/HP55 nanoparticles developed in the study might be employed as a potential method for oral insulin delivery.

  8. Advances of flue gas desulfurization technology for coal-fired boilers and strategies for sulfur dioxide pollution prevention in China

    SciTech Connect

    Yang, C.; Zeng, G.; Li, G.; Qiu, J.

    1999-07-01

    Coal is one of the most important kinds of energy resources at the present time and in the immediate future in China. Sulfur dioxide resulting from combustion of coal is one of the principle pollutants in the air. Control of SO{sub 2} discharge is still a major challenge for environmental protection in developing China. In this paper, research, development and application of technology of flue gas desulfurization (FGD) for coal-fired boilers in China will be reviewed with emphasis on cost-effective technology, and the development trends of FGD technology, as well as the strategy for SO{sub 2} discharge control in China, will be analyzed. A practical technology for middle-small-sized boilers developed by the primary author and the field investigation results will also be presented. At present, there are four major kinds of FGD technologies that are practical to be applied in China for their cost-effectiveness and efficiency to middle-small-sized boilers. An important development trend of the FGD technology for middle-small-sized boilers for the next decade is improvement of the existing cost-effective wet-type FGD technology, and in the future it will be the development of dry-type FGD technology. For middle-sized generating boilers, the development direction of the FGD technology is the spraying and drying process. For large-sized generating boilers, the wet-type limestone-plaster process will still be applied in the immediate future, and dry-type FGD technologies, such as ammonia with electron beam irradiation, will be developed in the future. State strategies for the control of SO{sub 2} discharge will involve the development and popularization of efficient coal-fired devices, extension of gas coal and liquefied coal, spreading coal washing, and centralized heating systems.

  9. Thermostabilization of desulfurization enzymes from Rhodococcos sp. IGTS8. Final technical report

    SciTech Connect

    John J. Kilbane II

    2000-12-15

    The objective of this project was to develop thermophilic cultures capable of expressing the desulfurization (dsz) operon of Rhodococcus sp. IGTS8. The approaches taken in this project included the development of plasmid and integrative expression vectors that function well in Thermus thermophilus, the cloning of Rhodococcus dsz genes in Thermus expression vectors, and the isolation of bacterial cultures that express the dsz operon at thermophilic temperatures. This project has resulted in the development of plasmid and integrative expression vectors for use in T. thermophilus. The dsz genes have been expressed at moderately thermophilic temperatures (52 C) in Mycobacterium phlei and at temperatures as high as 72 C in T. thermophilus. The tools and methods developed in this project will be generally useful for the expression of heterologous genes in Thermus. Key developments in the project have been the isolation of a Mycobacterium phlei culture capable of expressing the desulfurization operon at 52 C, development of plasmid and integrative expression vectors for Thermus thermophilus, and the development of a host-vector system based on the malate dehydrogenase gene that allows plasmids to be stably maintained in T. thermophilus and provides a convenient reporter gene for the accurate quantification of gene expression. Publications have been prepared regarding each of these topics; these preprints are included.

  10. Desulfurization of 4-methyl dibenzothiophene using titanium supported Keggin type polyoxometalate

    NASA Astrophysics Data System (ADS)

    Lesbani, Aldes; Anggraini, Ana; Mohadi, Risfidian; Rohendi, Dedi; Said, Muhammad

    2017-03-01

    Titanium supported Keggin type polyoxometalate H5PV2Mo10O40.nH2O has been prepared using tetra isopropyl orthotitanate by sol-gel method and microemulsion to form H5PV2Mo10O40/TiO2. Compound H5PV2Mo10O40.nH2O/TiO2 was characterized using FTTR spectroscopy, X-Ray analysis, and acidity measurement. FTTR spectrum showed that all vibration of titanium and polyoxometalate were appeared in H5PV2Mo10O40.nH2O/TiO2 with decreasing crystallinity. The acidity of H5PV2Mo10O40.nH2O/TiO2 was higher than H5PV2Mo10O40.nH2O. Desulfurization of 4-methyl dibenzothiophene (4-MDBT) using H5PV2Mo10O40.nH2O/TiO2 as catalyst resulted conversion of 4-MDBT was 99% and higher than desulfurization using H5PV2Mo10O40.nH2O under mild conditions.

  11. Status of METC investigations of coal gas desulfurization at high temperature. [Zinc ferrite

    SciTech Connect

    Steinfeld, G.

    1984-03-01

    This report documents the continuing effort at the US Department of Energy/Morgantown Energy Technology Center (METC) to develop a hot-gas desulfurization process for coal-derived gas, primarily for application to molten carbonate fuel cells. Metal oxide sorbents were tested on lab-scale test equipment, and it was determined that scale-up of the process was warranted. A larger, skid-mounted test unit was therefore designed, constructed, and installed on a sidestream of the DOE/METC fixed-bed gasifier. A first series of tests was conducted during Gasifier Run 101. These tests served to shake down the test unit, and provide data on the performance of the test unit operating on coal-derived gas. Overall, the process operated well on fixed-bed, air-blown gasifier gas. Sulfur levels in exit dry gas were reduced to less than 10 ppM. Regeneration appears to restore the sulfur-removing capacity of the sorbent. Sorbent integrity was maintained during the test period, which incorporated three sulfidations. It is recommended that treatment of the regeneration offgas be investigated, and that testing and development of a system to reduce the sulfur in this gas to elemental sulfur be initiated. In addition, it is suggested that a multiple reactor system be planned for continuous operation, to allow for long-term tests of downstream users of desulfurized gas. 7 references, 18 figures, 9 tables.

  12. Effect of the water-vapor content on the oxidative desulfurization of sulfur-rich coal

    SciTech Connect

    S. Pysh'yev; K. Shevchuk; L. Chmielarz; P. Kutrowski; A. Pattek-Janczyk

    2007-01-15

    Ukrainian sulfur-rich coal containing about 3.6 mass % of sulfur was studied. The desulfurization process was performed in the fluidized-bed reactor in dry (4 vol % of H{sub 2}O vapor) and wet (30-70 vol % of H{sub 2}O vapor) atmospheres in the temperature range of 350-450{sup o}C. A significant influence of the water-vapor content in the reaction mixture on the sulfur removal during the oxidative desulfurization of the coal was observed especially at low temperatures. The extent of FeS{sub 2} oxidation, the main sulfur-containing compound, was studied by Moessbauer spectroscopy. The Moessbauer data revealed different iron-containing products (FeSO{sub 4}nH{sub 2}O, Fe{sub 2}O{sub 3}, Fe{sub 3}O{sub 4}, and Fe{sub 1-x}S) formed in the course of the process carried out in dry and wet atmospheres. The promoting effect of water vapor on the pyrite transformation was observed especially at low temperatures. The mechanism of this promotion on the molecular scale was proposed. 19 refs., 6 figs., 4 tabs.

  13. Hg2+ reduction and re-emission from simulated wet flue gas desulfurization liquors.

    PubMed

    Wo, Jingjing; Zhang, Meng; Cheng, Xiaoya; Zhong, Xiaohang; Xu, Jiang; Xu, Xinhua

    2009-12-30

    In this study, considering that Hg(2+) in wet flue gas desulfurization (FGD) systems can easily be reduced and then released into atmosphere, causing secondary pollution, the researches about Hg(2+) reduction and Hg(0) re-emission mechanism were carried out. The effects of several experimental parameters on the reduction were studied, including initial pH, temperature, and concentrations of Cl(-) and S(IV). Our experimental results indicated that Cl(-) had a restraining effect on the Hg(2+) reduction and Hg(0) re-emission, after 24h reaction, only 20.5% of Hg(2+) was reduced with 100mM Cl(-) in simulated desulfurization solution. Cl(-) can slow Hg(2+) reduction and Hg(0) re-emissions dramatically through changing reaction mechanism, with formation of new intermediate: ClHgSO(3)(-), which can decompose to Hg(0), but much more slowly than Hg(SO(3))(2)(2-) or HgSO(3). Simulating the conditions of the practical application (initial pH 5, T=50 degrees C, S(IV)=5 mM, Cl(-)=100 mM), we also found that Ca(2+), NO(3)(-), F(-), etc. all had obvious effects on reduction rates. Based on the material balance and characteristic of the reactants, the reduction emission mechanism of Hg(2+) has been established, providing theoretical basis for industrial application of mercury control in wet FGD systems.

  14. Distribution and quality of carbonate rock for desulfurization in coal combustion processes

    SciTech Connect

    Eggleston, J.R.; Kress, T.H.

    1995-12-31

    To meet the requirements of the Federal Clean Air Act of 1970 and the Amendments of 1977 and 1990, coal-burning power plants will use large tonnages of carbonate rock (limestone and dolomite) and lime for flue gas desulfurization, fluidized bed combustion, and other processes designed to minimize air pollution. By January 1, 2000, the end of Phase 2 of Title IV of the Clean Air Act, all plants having a capacity of 25 MW or more must restrict their sulfur emissions to 1.2 lb per million Btu or less. As power companies endeavor to comply with this regulation, they will need to identify resources of limestone and dolomite having specific quality and grindability characteristics, in sufficient quantity for their needs and within proximity to their plants. A study is underway at the US Geological Survey (USGS) to identify limestone resources in the Eastern US that are best suited for desulfurization in the various combustion systems. Carbonate resources are being identified, quantified, and characterized on the basis of their sorbent properties and proximity to potential markets. In addition, the USGS has developed a carbonate data base that includes approximately 1,500 chemically analyzed samples from the US. The current study focuses on limestones that are suited for wet scrubber operations and have at least 90% CaCO{sub 3}.

  15. Use Of limestone resources in flue-gas desulfurization power plants in the Ohio River Valley

    USGS Publications Warehouse

    Foose, M.P.; Barsotti, A.F.

    1999-01-01

    In 1994, more than 41 of the approximately 160 coal-fired, electrical- power plants within the six-state Ohio River Valley region used flue-gas desulfurization (FGD) units to desulfurize their emissions, an approximately 100% increase over the number of plants using FGD units in 1989. This increase represents a trend that may continue with greater efforts to meet Federal Clean Air Act standards. Abundant limestone resources exist in the Ohio River Valley and are accessed by approximately 975 quarries. However, only 35 of these are believed to have supplied limestone for FGD electrical generating facilities. The locations of these limestone suppliers do not show a simple spatial correlation with FGD facilities, and the closest quarries are not being used in most cases. Thus, reduction in transportation costs may be possible in some cases. Most waste generated by FGD electrical-generating plants is not recycled. However, many FGD sites are relatively close to gypsum wallboard producers that may be able to process some of their waste.

  16. Potential Agricultural Uses of Flue Gas Desulfurization Gypsum in the Northern Great Plains

    SciTech Connect

    DeSutter, T.M.; Cihacek, L.J.

    2009-07-15

    Flue gas desulfurization gypsum (FGDG) is a byproduct from the combustion of coal for electrical energy production. Currently, FGDG is being produced by 15 electrical generating stations in Alabama, Florida, Indiana, Iowa, Kentucky, Ohio, North Carolina, South Carolina, Tennessee, Texas, and Wisconsin. Much of this byproduct is used in the manufacturing of wallboard. The National Network for Use of FGDG in Agriculture was initiated to explore alternative uses of this byproduct. In the northern Great Plains (North Dakota, South Dakota, and Montana), FGDG has the potential to be used as a Ca or S fertilizer, as an acid soil ameliorant, and for reclaiming or mitigating sodium-affected soils. Greater than 1.4 million Mg of FGDG could initially be used in these states for these purposes. Flue gas desulfurization gypsum can be an agriculturally important resource for helping to increase the usefulness of problem soils and to increase crop and rangeland production. Conducting beneficial use audits would increase the public awareness of this product and help identify to coal combustion electrical generating stations the agriculturally beneficial outlets for this byproduct.

  17. Efficient desulfurization by polymer-inorganic nanocomposite membranes fabricated in reverse microemulsion.

    PubMed

    Li, Ben; Yu, Shengnan; Jiang, Zhongyi; Liu, Wanpeng; Cao, Ruijian; Wu, Hong

    2012-04-15

    The sulfur in gasoline will convert to SO(2) after combustion under high temperature, which adversely affects human health and the environment. Membrane technique in particular pervaporation offers a number of potential advantages over conventional FCC gasoline desulfurization processes. The present study focuses on the performance enhancement of PDMS membrane by incorporating silica nanoparticles. Specifically, silica nanoparticles formed by the catalysis and templating of protamine in w/o reverse microemulsion are in situ embedded into PDMS bulk matrix, endowing the resultant oleophilic nanocomposite membranes with appropriate free volume properties and superior separation performance. Through the rational manipulation of biomimetic mineralization at water-oil interface, silica particles with uniform size are acquired. Following this protocol, by introducing organic PDMS oligomers into the oil phase, PDMS-SiO(2) nanocomposite membranes are prepared in a facile way. The resultant nanocomposite membranes display superior permeability and permselectivity in the pervaporative desulfurization using thiophene/n-octane binary mixture as model gasoline, for example, under the condition of 500 ppm sulfur in feed (40 L/h) at 30°C, an enrichment factor of 4.83-5.82 with a normalized permeation rate of 6.61-10.76 × 10(-5)kgm/m(2)h is acquired.

  18. Catalytic seawater flue gas desulfurization process: an experimental pilot plant study

    SciTech Connect

    F. Vidal B.; P. Ollero; F.J. Gutierrez Ortiz; A. Villanueva

    2007-10-15

    In previous articles by the authors on seawater S(IV) oxidation kinetics, a significant catalytic effect was demonstrated by means of a commercially available activated carbon. The aims of this study carried out at pilot plant scale were to assess the use of high-efficiency structured packing and to validate the positive results obtained previously in laboratory studies. A comparison between a packed tower and a spray column was made by maintaining the same desulfurization efficiency. A 47% reduction in seawater flow can be obtained with a packed tower. This option seems to be more economical, with a reduction in operation costs of least of 33%. With the appropriate activated carbon, it is possible to reach a greater oxidation rate at a low pH level than by operating conventionally at a high pH level without a catalyst. A preliminary technical and financial comparison between the advanced seawater desulfurization process (equipped with a packed tower and a catalytic oxidation plant) and the conventional process (spray tower and noncatalytic oxidation) was carried out. 18 refs., 4 figs., 4 tabs.

  19. Land application uses for dry flue gas desulfurization by-products: Phase 3

    SciTech Connect

    Dick, W.; Bigham, J.; Forster, R.; Hitzhusen, F.; Lal, R.; Stehouwer, R.; Traina, S.; Wolfe, W.; Haefner, R.; Rowe, G.

    1999-01-31

    New flue gas desulfurization (FGD) scrubbing technologies create a dry, solid by-product material consisting of excess sorbent, reaction product that contains sulfate and sulfite, and coal fly ash. Generally, dry FGD by-products are treated as solid wastes and disposed in landfills. However, landfill sites are becoming scarce and tipping fees are constantly increasing. Provided the environmental impacts are socially and scientifically acceptable, beneficial uses via recycling can provide economic benefits to both the producer and the end user of the FGD. A study titled ''Land Application Uses for Dry Flue Gas Desulfurization By-Products'' was initiated in December, 1990 to develop and demonstrate large volume, beneficial uses of FGD by-products. Phase 1 and Phase 2 reports have been published by the Electric Power Research Institute (EPRI), Palo Alto, CA. Phase 3 objectives were to demonstrate, using field studies, the beneficial uses of FGD by-products (1) as an amendment material on agricultural lands and on abandoned surface coal mine land, (2) as an engineering material for soil stabilization and raid repair, and (3) to assess the environmental and economic impacts of such beneficial uses. Application of dry FGD by-product to three soils in place of agricultural limestone increased alfalfa (Medicago sativa L.) and corn (Zea may L.) yields. No detrimental effects on soil and plant quality were observed.

  20. Three-dimensional interconnected nickel phosphide networks with hollow microstructures and desulfurization performance

    SciTech Connect

    Zhang, Shuna; Zhang, Shujuan; Song, Limin; Wu, Xiaoqing; Fang, Sheng

    2014-05-01

    Graphical abstract: Three-dimensional interconnected nickel phosphide networks with hollow microstructures and desulfurization performance. - Highlights: • Three-dimensional Ni{sub 2}P has been prepared using foam nickel as a template. • The microstructures interconnected and formed sponge-like porous networks. • Three-dimensional Ni{sub 2}P shows superior hydrodesulfurization activity. - Abstract: Three-dimensional microstructured nickel phosphide (Ni{sub 2}P) was fabricated by the reaction between foam nickel (Ni) and phosphorus red. The as-prepared Ni{sub 2}P samples, as interconnected networks, maintained the original mesh structure of foamed nickel. The crystal structure and morphology of the as-synthesized Ni{sub 2}P were characterized by X-ray diffraction, scanning electron microscopy, automatic mercury porosimetry and X-ray photoelectron spectroscopy. The SEM study showed adjacent hollow branches were mutually interconnected to form sponge-like networks. The investigation on pore structure provided detailed information for the hollow microstructures. The growth mechanism for the three-dimensionally structured Ni{sub 2}P was postulated and discussed in detail. To investigate its catalytic properties, SiO{sub 2} supported three-dimensional Ni{sub 2}P was prepared successfully and evaluated for the hydrodesulfurization (HDS) of dibenzothiophene (DBT). DBT molecules were mostly hydrogenated and then desulfurized by Ni{sub 2}P/SiO{sub 2}.

  1. [Influence and mechanism of calcium-based desulfurizer on NO conversion in fluidized bed of coal].

    PubMed

    Zhang, Dongping; Chi, Yong; Yan, Jianhua; Li, Xiangpai; Cao, Yuchun; Cen, Kefa

    2003-01-01

    On the experimental table of fluidized bed which scale was phi 150 mm x 1000 mm and temperature interval was from 840 degrees C to 960 degrees C, the influence of desulfurizer variety, particle size and molar ratios Ca/S on nitrogen conversion to NO were studied. This paper elaborated on the mechanism of calcium-based desulfurizer lead to the increase of NO conversion rate. Experiment presented that given identical quantities, burnt calcium had maximum NO conversion rate, then limestone, calcite last. Nitrogen conversion to NO increased with increasing molar ratios Ca/S. When the particle size was between 1-2 mm, the NO conversion rate was the maximum, second was 2-3 mm, the last 0.2-1 mm. HCl, HF, SO2 decreased with calcium addition. At the same time H, OH, HO2 radicals increased. The CO oxidation was favored, the reaction of monoxide and NO catalyzed by char, sand, ash will weaken, therefore NO content will increase.

  2. Hot coal gas desulfurization with manganese-based sorbents. Final report, September 1992--December 1994

    SciTech Connect

    Hepworth, M.T.; Slimane, R.B.

    1994-11-01

    The focus of much current work being performed by the Morgantown Energy Technology Center (METC) of the Department of Energy on hot coal-derived fuel gas desulfurization is in the use of zinc-based sorbents. METC has shown interest in formulating and testing manganese-based pellets as alternative effective sulfur sorbents in the 700 to 1200{degree}C temperature range. To substantiate the potential superiority of Mn-based pellets, a systematic approach toward the evaluation of the desulfurizing power of single-metal sorbents is developed based on thermodynamic considerations. This novel procedure considered several metal-based sorbents and singled out manganese oxide as a prime candidate sorbent capable of being utilized under a wide temperature range, irrespective of the reducing power (determined by CO{sub 2}/CO ratio) of the fuel gas. Then, the thermodynamic feasibility of using Mn-based pellets for the removal of H{sub 2}S from hot-coal derived fuel gases, and the subsequent oxidative regeneration of loaded (sulfided) pellets was established. It was concluded that MnO is the stable form of manganese for virtually all commercially available coal-derived fuel gases. In addition, the objective of reducing the H{sub 2}S concentration below 150 ppMv to satisfy the integrated gasification combined cycle system requirement was shown to be thermodynamically feasible. A novel process is developed for the manufacture of Mn-based spherical pellets which have the desired physical and chemical characteristics required.

  3. A potassium tert-butoxide and hydrosilane system for ultra-deep desulfurization of fuels

    NASA Astrophysics Data System (ADS)

    Toutov, Anton A.; Salata, Mike; Fedorov, Alexey; Yang, Yun-Fang; Liang, Yong; Cariou, Renan; Betz, Kerry N.; Couzijn, Erik P. A.; Shabaker, John W.; Houk, Kendall N.; Grubbs, Robert H.

    2017-02-01

    Hydrodesulfurization (HDS) is the process by which sulfur-containing impurities are removed from petroleum streams, typically using a heterogeneous, sulfided transition metal catalyst under high H2 pressures and temperatures. Although generally effective, a major obstacle that remains is the desulfurization of highly refractory sulfur-containing heterocycles, such as 4,6-dimethyldibenzothiophene (4,6-Me2DBT), which are naturally occurring in fossil fuels. Homogeneous HDS strategies using well-defined molecular catalysts have been designed to target these recalcitrant S-heterocycles; however, the formation of stable transition metal sulfide complexes following C-S bond activation has largely prevented catalytic turnover. Here we show that a robust potassium (K) alkoxide (O)/hydrosilane (Si)-based ('KOSi') system efficiently desulfurizes refractory sulfur heterocycles. Subjecting sulfur-rich diesel (that is, [S] ∼ 10,000 ppm) to KOSi conditions results in a fuel with [S] ∼ 2 ppm, surpassing ambitious future governmental regulatory goals set for fuel sulfur content in all countries.

  4. Negative-tone imaging with EUV exposure for 14nm hp and beyond

    NASA Astrophysics Data System (ADS)

    Tsubaki, Hideaki; Nihashi, Wataru; Tsuchihashi, Toru; Fujimori, Toru; Momota, Makoto; Goto, Takahiro

    2015-03-01

    Manipulation of dissolution properties by changing organic solvent developer and rinse material provides a novel technology to obtain fine pattern beyond the limitation of imaging system based on alkaline developer. QCM study showed no swelling character in negative-tone imaging (NTI) process even for current developer of n-butyl acetate (nBA). Actually, NTI process has shown advantages on resolution and line-width roughness (LWR) in loose pitch around 30 ~ 45 nm hp as a consequence of its non-swelling character. On the other hand, bridge and collapse limited its resolution below 20 nm hp, indicating that non-negligible amount of swelling still exists for tight pitch resolution. We investigated effects of solubility parameter of organic solvents on resolution below 20 nm hp. A bridge was reduced with a decrease in the solubility parameter dp from nBA. On the other hand, much lower dp caused film remaining due to its extremely slow Rmax. Based on these results, we newly developed FN-DP301 containing organic solvent with smaller dp than nBA. Although rinse solvent gave negligible effects on bridge, there is a clear improvement on pattern collapse only in case of using new rinse solvent of FN-RP311. Lithographic performances of NTI process using nBA and FN-DP301 together with the other organic solvents were described in this paper under exposures with an E-beam and a EUV light. It is emphasized that 14 nm hp resolution was obtained only using FN-DP301 as a developer and FN-RP311 as a rinse under E-beam exposure. NTI showed 43% faster photospeed in comparison with PTI at 16 nm hp, indicating that NTI is applicable to obtain high throughput with maintaining resolution. In addition, sub-20 nm trench was obtained using NTI without bridge under EUV exposure, all of which are attributed to the low swelling character of NTI process. Similarly, NTI was able to print 20 nm dots using NXE:3100 with only a little peeling. Conversely CH patterning was significantly worse with NTI

  5. HP 0.35, a cephalosporin degradation product is a specific inhibitor of lentiviral RNAses H.

    PubMed Central

    Hafkemeyer, P; Neftel, K; Hobi, R; Pfaltz, A; Lutz, H; Lüthi, K; Focher, F; Spadari, S; Hübscher, U

    1991-01-01

    Penicillins, cephalosporins and other betalactam antibiotics are widely used antibacterial drugs. Recently it was found that some of them also have effects on proliferating eukaryotic cells (Neftel, K.A. and Hübscher, U. (1987) Antimicrob. Agents Chemother. 31, 1657-1661), and one such effect was shown to be the inhibition of DNA polymerase alpha (Huynh Do,U., Neftel, K.A., Spadari, S. and Hübscher, U. (1987) Nucl. Acids Res. 15, 10495-10506). The data suggested that degradation products of betalactam antibiotics were responsible for the inhibitory effect on DNA polymerase alpha. There is some confirmation at the structural level, since we found that penicillin binding proteins, the natural target of the cephalosporins, share amino-acid homologies to DNA polymerases and also to reverse transcriptase from HIV1 (Hafkemeyer, P., Neftel, K.A. and Hübscher, U. Meth. Find. Exp. Clin. Pharmacol. 12, 43-46, 1990). We have purified and determined the structure of one product from the cephalosporin Ceftazidim and found one molecule (HP 0.35) that did not interfere with eukaryotic cell proliferation but rather had a specific inhibitory effect on the RNase H activity of human immunodeficiency virus 1 (HIV1) and feline immunodeficiency virus (FIV) reverse transcriptases, while the DNA polymerising activity of these enzymes was not affected. RNases H from HeLa cells, calf thymus and Escherichia coli on the other hand were much less affected by HP 0.35. The inhibitory concentration of 50% (IC50) was more than 10 times lower compared to those of all cellular RNases H. We therefore tested the effect of HP 0.35 on in vitro lentivirus infection as exemplified by FIV-infection of CD(4+)-cat lymphocytes in cell culture. Under conditions where cell proliferation was absolutely unaffected, HP 0.35 was able to inhibit FIV-infection in CD(4+)-cat lymphocytes. Moreover, preincubation of these lymphocytes with HP 0.35 rendered the cells completely unsusceptible to FIV-infection. These

  6. Desulfurization in reducing atmosphere and ammonia injection denitrification in a coal-fired fluidized bed combustor with fly-ash recycle

    NASA Astrophysics Data System (ADS)

    Zhong, Zhaoping; Lan, Jixiang; Han, Yongsheng; Wu, Xin; Zheng, Haiyun

    1997-03-01

    With the rising of IGCC and the second generation PFBC-CC, and with the development of technology of staged combustion to lower emission of NOx, the desulfurization efficiency under reducing atmosphere is raised. In this paper, with the application of the fly-ash recycle and two-stage combustion technologies in a fluidized bed combustor, the desulfurization test under reducing atmosphere is described. Meanwhile, ammonia injection test was also conducted. Results show that desulfurization under reducing atmosphere has higher efficiency, and ammonia injection denitrification effect is very perfect.

  7. Advanced Flue Gas Desulfurization (AFGD) Demonstration Project, A DOE Assessment

    SciTech Connect

    National Energy Technology Laboratory

    2001-08-31

    The AFGD process as demonstrated by Pure Air at the Bailly Station offers a reliable and cost-effective means of achieving a high degree of SO{sub 2} emissions reduction when burning high-sulfur coals. Many innovative features have been successfully incorporated in this process, and it is ready for widespread commercial use. The system uses a single-loop cocurrent scrubbing process with in-situ oxidation to produce wallboard-grade gypsum instead of wet sludge. A novel wastewater evaporation system minimizes effluents. The advanced scrubbing process uses a common absorber to serve multiple boilers, thereby saving on capital through economies of scale. Major results of the project are: (1) SO{sub 2} removal of over 94 percent was achieved over the three-year demonstration period, with a system availability exceeding 99.5 percent; (2) a large, single absorber handled the combined flue gas of boilers generating 528 MWe of power, and no spares were required; (3) direct injection of pulverized limestone into the absorber was successful; (4) Wastewater evaporation eliminated the need for liquid waste disposal; and (5) the gypsum by-product was used directly for wallboard manufacture, eliminating the need to dispose of waste sludge.

  8. Elemental sulfur recovery from desulfurization sorbents in advanced power systems

    SciTech Connect

    Dorchak, T.P.; Gangwal, S.K.; Turk, B.S.

    1995-12-31

    Regenerable metal oxide sorbents, such as zinc titanate, are being developed to efficiently remove hydrogen sulfide (H{sub 2}S) from coal gas in advanced power systems. Dilute air regeneration of the sorbents produces a tailgas containing a few percent sulfur dioxide (SO{sub 2}). Catalytic reduction of the SO{sub 2} to elemental sulfur with a coal gas slipstream using the Direct Sulfur Recovery Process (DSRP) is a leading first-generation technology. Currently the DSRP is undergoing field testing at gasifier sites. The objective of this study is to develop second-generation processes that produce elemental sulfur with limited use of coal gas. Novel approaches that were evaluated to produce elemental sulfur from sulfided sorbents include (1) SO{sub 2} regeneration, (2) substoichiometric oxidation, (3) steam regeneration followed by H{sub 2}S oxidation, and (4) steam-air regeneration. Experimental results at high temperature and high pressure demonstrate that, with simple sorbent modifications, direct regeneration to elemental sulfur is feasible without the use of coal gas.

  9. A green surfactant-assisted synthesis of hierarchical TS-1 zeolites with excellent catalytic properties for oxidative desulfurization.

    PubMed

    Du, Shuting; Li, Fen; Sun, Qiming; Wang, Ning; Jia, Mingjun; Yu, Jihong

    2016-02-25

    Hierarchical TS-1 zeolites with uniform intracrystalline mesopores have been successfully synthesized through the hydrothermal method by using the green and cheap surfactant Triton X-100 as the mesoporous template. The resultant materials exhibit remarkably enhanced catalytic activity in oxidative desulfurization reactions compared to the conventional TS-1 zeolite.

  10. Impact of Leaching Conditions on Constituents Release from Flue Gas Desulfurization Gypsum (FGDG) and FGDG-Soil Mixture

    EPA Science Inventory

    The interest in using Flue Gas Desulfurization Gypsum(FGDG) has increased recently. This study evaluates the leaching characteristics of trace elements in "modern" FGDG (produced after fly ash removal) and FGDG-mixed soil (SF) under different environmental conditions using rece...

  11. Synthesis, characterization and application of 1-butyl-3 methylimidazolium chloride as green material for extractive desulfurization of liquid fuel.

    PubMed

    Dharaskar, Swapnil A; Varma, Mahesh N; Shende, Diwakar Z; Yoo, Chang Kyoo; Wasewar, Kailas L

    2013-01-01

    The possible application of imidazolium ionic liquids as energy-efficient green material for extractive deep desulfurization of liquid fuel has been investigated. 1-Butyl-3-methylimidazolium chloride [BMIM]Cl was synthesized by nucleophilic substitution reaction of n-methylimidazolium and 1-chlorobutane. Molecular structures of the ILs were confirmed by FTIR, (1)H-NMR, and (13)C-NMR. The thermal properties, conductivity, solubility, water content and viscosity analysis of [BMIM]Cl were carried out. The effects of reaction time, reaction temperature, sulfur compounds, and recycling of IL without regeneration on dibenzothiophene removal of liquid fuel were presented. In the extractive desulfurization process, the removal of dibenzothiophene in n-dodecane using [BMIM]Cl was 81% with mass ratio of 1 : 1, in 30 min at 30°C under the mild reaction conditions. Also, desulfurization of real fuels with IL and multistage extraction were studied. The results of this work might offer significant insights in the perceptive use of imidazoled ILs as energy-efficient green material for extractive deep desulfurization of liquid fuels as it can be reused without regeneration with considerable extraction efficiency.

  12. Synthesis, Characterization and Application of 1-Butyl-3 Methylimidazolium Chloride as Green Material for Extractive Desulfurization of Liquid Fuel

    PubMed Central

    Dharaskar, Swapnil A.; Varma, Mahesh N.; Shende, Diwakar Z.; Yoo, Chang Kyoo; Wasewar, Kailas L.

    2013-01-01

    The possible application of imidazolium ionic liquids as energy-efficient green material for extractive deep desulfurization of liquid fuel has been investigated. 1-Butyl-3-methylimidazolium chloride [BMIM]Cl was synthesized by nucleophilic substitution reaction of n-methylimidazolium and 1-chlorobutane. Molecular structures of the ILs were confirmed by FTIR, 1H-NMR, and 13C-NMR. The thermal properties, conductivity, solubility, water content and viscosity analysis of [BMIM]Cl were carried out. The effects of reaction time, reaction temperature, sulfur compounds, and recycling of IL without regeneration on dibenzothiophene removal of liquid fuel were presented. In the extractive desulfurization process, the removal of dibenzothiophene in n-dodecane using [BMIM]Cl was 81% with mass ratio of 1 : 1, in 30 min at 30°C under the mild reaction conditions. Also, desulfurization of real fuels with IL and multistage extraction were studied. The results of this work might offer significant insights in the perceptive use of imidazoled ILs as energy-efficient green material for extractive deep desulfurization of liquid fuels as it can be reused without regeneration with considerable extraction efficiency. PMID:24307868

  13. A template-free solvent-mediated synthesis of high surface area boron nitride nanosheets for aerobic oxidative desulfurization.

    PubMed

    Wu, Peiwen; Zhu, Wenshuai; Chao, Yanhong; Zhang, Jinshui; Zhang, Pengfei; Zhu, Huiyuan; Li, Changfeng; Chen, Zhigang; Li, Huaming; Dai, Sheng

    2016-01-04

    Hexagonal boron nitride nanosheets (h-BNNs) with rather high specific surface area (SSA) are important two-dimensional layer-structured materials. Here, a solvent-mediated synthesis of h-BNNs revealed a template-free lattice plane control strategy that induced high SSA nanoporous structured h-BNNs with outstanding aerobic oxidative desulfurization performance.

  14. High H2O-resistance CaO-MnOx/MSU-H sorbents for hot coal gas desulfurization.

    PubMed

    Xia, Hong; Liu, Bingsi

    2017-02-15

    A series of xMnyCa/MSU-H sorbents with various Mn/Ca molar ratio were first designed and synthesized with a sol-gel method. The desulfurization performance of the new sorbent was investigated at 600-800°C in hot coal gas. 90Mn10Ca/MSU-H exhibited better desulfurization performance at 750°C with a breakthrough sulfur capacity (BSC) of 18.69g S/100g sorbent compared to other supported Mn-based sorbents (13.2g S/100g sorbent) in similar desulfurization condition, and strong durability in multiple sulfidation-regeneration cycles using oxidation/reduction regeneration method which resolved the scientific issue of that CaSO4 is hardly decomposed to CaO. The introduction of Ca species effectively promoted the dispersion of active constituents, which improved the desulfurization activity. More importantly, 90Mn10Ca/MSU-H showed excellent H2O-resistance ability due to the fact that CaO enhanced the sorption of H2O. Moreover, the utilization of MSU-H with large pore size and excellent thermal stability effectively assured fast mass-transfer and confined the migration of active particles, which led to long lifetime stability of sorbents.

  15. Use of animal waste and flue gas desulfurized gypsum to improve forage production on reclaimed mine soil in Mississippi

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Reclaimed mine soils amended with flue gas desulfurized (FGD) gypsum may tolerate higher levels of animal manure, and would therefore be more productive in the long-term. Studies were conducted in respread soil during the first year of land reclamation at Red Hills Mine, a surface lignite mine in no...

  16. Three annual flue gas desulfurization gypsum applications on macronutrient and micronutrient losses in runoff from bermudagrass fertilized with poultry litter

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Considerable amounts of flue gas desulfurization (FGD) gypsum are being produced as a by-product of generating electricity. As a result, beneficial reuse of this by-product is being sought to reduce landfilling and its associated cost. The use of this byproduct as a low-cost soil amendment for suppl...

  17. Mercury emission and plant uptake of trace elements during early stage of soil amendment using flue gas desulfurization materials.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A pilot-scale field study was carried out to investigate the distribution of Hg and other selected elements in the three potential mitigation pathways, i.e., emission to ambient air, uptake by surface vegetation (i.e., grass), and rainfall infiltration, after flue gas desulfurization (FGD) material ...

  18. Desulfurization characteristics of rapidly hydrated sorbents with various adhesive carrier particles for a semidry CFB-FGD system.

    PubMed

    You, Changfu; Li, Yuan

    2013-03-19

    Semidry flue gas desulfurization (FGD) experiments were conducted using rapidly hydrated sorbents with four different adhesive carrier particles: circulation ash from a circulating fluidized bed boiler (CFBB circulation ash), fly ash from the first electrical field of the electrostatic precipitator of a circulating fluidized bed boiler (CFBB ESP ash), fly ash from a chain boiler (chain boiler ash), and river sand smaller than 1 mm. The influences of various adhesive carrier particles and operating conditions on the desulfurization characteristics of the sorbents were investigated, including sprayed water, reaction temperature, and the ratio of calcium to sulfur (Ca/S). The experimental results indicated that the rapidly hydrated sorbents had better desulfurization characteristics by using adhesive carrier particles which possessed better pore, adhesion, and fluidization characteristics. The desulfurization efficiency of the system increased as the reaction temperature decreased, it improved from 35% to 90% as the mass flow rate of the sprayed water increased from 0 to 10 kg/h, and it increased from 65.6% to 82.7% as Ca/S increased from 1.0 to 2.0. Based on these findings, a new semidry circulating fluidized bed (CFB)-FGD system using rapidly hydrated sorbent was developed. Using the rapidly hydrated sorbent, this system uses a cyclone separator instead of an ESP or a bag filter to recycle the sorbent particles, thereby decreasing the system flow resistance, saving investment and operating costs of the solids collection equipment.

  19. 75 FR 41531 - Hewlett Packard (HP) Global Product Development, Working On-Site at General Motors Corporation...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-16

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF LABOR Employment and Training Administration Hewlett Packard (HP) Global Product Development, Working On-Site at General Motors Corporation, Milford, MI; Notice of Revised Termination of Investigation Pursuant...

  20. A Comparison between the hp-version of Finite Element Method with EIDORS for Electrical Impedance Tomography.

    PubMed

    Saeedizadeh, N; Kermani, S; Rabbani, H

    2011-07-01

    In this study, a hp-version of Finite Element Method (FEM) was applied for forward modeling in image reconstruction of Electrical Impedance Tomography (EIT). The EIT forward solver is normally based on the conventional Finite Element Method (h-FEM). In h-FEM, the polynomial order (p) of the element shape functions is constant and the element size (h) is decreasing. To have an accurate simulation with the h-FEM, a mesh with large number of nodes and elements is usually needed. In order to overcome this problem, the high order finite element method (p-FEM) was proposed. In the p-version, the polynomial order is increasing and the mesh size is constant. Combining the advantages of two previously mentioned methods, the element size (h) was decreased and the polynomial order (p) was increased, simultaneously, which is called the hp-version of Finite Element Method (hp-FEM). The hp-FEM needs a smaller number of nodes and consequently, less computational time and less memory to achieve the same or even better accuracy than h-FEM. The SNR value is 42db for hp-FEM and is 9db for h-FEM. The numerical results are presented and verified that the performance of the hp-version is better than of the h-version in image reconstruction of EIT.

  1. Investigation of the inclusion behavior of HP-β-cyclodextrin with polydatin in solution and its analytical application

    NASA Astrophysics Data System (ADS)

    An, Songsong; He, Jiang; Sun, Lijuan; Ren, Dong; Ban, Yihe

    2013-04-01

    The inclusion complex of the slight water solubility, polydatin (PD), with hydroxypropyl-β-cyclodextrin (HP-β-CD) was investigated for the first time in solution. The effect of HP-β-CD on the spectral feature of PD was measured using fluorescence technique by varying the concentrations of HP-β-CD. Meanwhile, the molecular mechanism of the formation of inclusion complex of PD with HP-β-CD was studied and discussed by molecular modeling. The experimental result clearly indicated that the benzene ring of PD was encapsulated within the HP-β-CD cavity to form a 1:1 stoichiometry host-guest compound. The apparent formation constants (K) was obtained by the typical double reciprocal plots and phase solubility studies. Due to the remarkable enhancement of the fluorescence intensity of PD, a spectrofluorimetric method was developed for the determination of PD in bulk aqueous solution in the presence of HP-β-CD. The linear range was 2.00 × 10-7-2.00 × 10-5 mol/L (r = 0.998) with the detection limit 9.50 × 10-9 mol/L. The present study provided useful information for a more rational determination of PD in serum with recoveries of 97-104%.

  2. Hinge and chromoshadow of HP1α participate in recognition of K9 methylated histone H3 in nucleosomes.

    PubMed

    Mishima, Yuichi; Watanabe, Makoto; Kawakami, Toru; Jayasinghe, Chanika D; Otani, Junji; Kikugawa, Yusuke; Shirakawa, Masahiro; Kimura, Hiroshi; Nishimura, Osamu; Aimoto, Saburo; Tajima, Shoji; Suetake, Isao

    2013-01-09

    The majority of the genome in eukaryotes is packaged into transcriptionally inactive chromatin. Heterochromatin protein 1 (HP1) is a major player in the establishment and maintenance of heterochromatin. HP1 specifically recognizes a methylated lysine residue at position 9 in histone H3 through its N-terminal chromo domain (CD). To elucidate the binding properties of HP1α to nucleosomes in vitro, we reconstituted nucleosomes containing histone H3 trimethylated at lysine 9. HP1α exhibited high-affinity binding to nucleosomes containing methylated histone H3 in a nucleosome core-number-dependent manner. The hinge region (HR) connecting the CD and C-terminal chromoshadow domain (CSD), and the CSD contributed to the selective binding of HP1α to histone H3 with trimethylated lysine 9 through weak DNA binding and by suppressing the DNA binding, respectively. We propose that not only the specific recognition of lysine 9 methylation of histone H3 by the CD but also the HR and the CSD cooperatively contribute to the selective binding of HP1α to histone H3 lysine 9 methylated nucleosomes.

  3. HP-NAP inhibits the growth of bladder cancer in mice by activating a cytotoxic Th1 response.

    PubMed

    Codolo, Gaia; Fassan, Matteo; Munari, Fabio; Volpe, Andrea; Bassi, Piefrancesco; Rugge, Massimo; Pagano, Francesco; D'Elios, Mario Milco; de Bernard, Marina

    2012-01-01

    Intravesical Bacillus Calmette-Guérin (BCG) is the gold standard treatment for intermediate and high-risk non-muscle-invasive bladder cancer. BCG therapy is the most successful example of immunotherapy in cancer. Unfortunately, the treatment-related side effects are still relevant. Furthermore, non-responder patients are candidate to radical cystectomy in the absence of valuable alternative options. These aspects have prompted the search for newer biological response modifiers (BRM) with a better benefit/side effects ratio. The toll-like receptor (TLR) 2 ligand, Helicobacter pylori protein HP-NAP, has been shown to deserve a potential role as BRM. HP-NAP is capable of driving the differentiation of T helper (Th) 1 cells, both in vitro and in vivo, because of its ability to create an IL-12-enriched milieu. Herein, we report that local administration of HP-NAP decreases tumour growth by triggering tumour necrosis in a mouse model of bladder cancer implant. The effect is accompanied by a significant accumulation of both CD4+ and CD8+ IFN-γ-secreting cells, within tumour and regional lymph nodes. Noteworthy, HP-NAP-treated tumours show also a reduced vascularization due to the anti-angiogenic activity of IFN-γ induced by HP-NAP. Our findings strongly indicate that HP-NAP might become a novel therapeutic "bullet" for the cure of bladder tumours.

  4. Strength of Hycon 3 HP Be-Cu and other copper alloys from 20 C to 200 C

    NASA Astrophysics Data System (ADS)

    Weggel, Robert J.; Ratka, John O.; Spiegelberg, William D.; Sakai, Yoshikazu

    1994-07-01

    To be suitable for high-performance water-cooled magnets a conductor must have an excellent combination of electrical conductivity and tensile strength at moderately elevated temperatures. We have measured the 0.2% yield and ultimate tensile strengths, elongation and modulus of five copper alloys, in the form of heavily cold-worked strip 0.4 mm to 1.2 mm thick, at temperatures up to 200 C. The alloys are Hycon 3 HP Be-Cu (UNS alloy C17510), a 24% silver-copper being developed by NRIM (Tsukuba, Japan), Glidcop(sup (R)), Zr-Cu and electrolytic tough pitch copper. Be-Cu, Zr-Cu and Ag-Cu all retained strength very well. Be-Cu decreased in U.T.S. only 10% from room temperature to 200 C, Zr-Cu, 15%. For Ag-Cu the decrease was 10% from 20 C to 150 C, and another 10% during the next 50 C. Glidcop weakened 20% by 150 C. So did ETP copper, whose strength then plummeted another 50% by 200 C. Except for Ag-Cu, with its filamentary microstructure, all alloys were isotropic within about 5%. The anisotropy of Ag-Cu was about 12%, with the transverse direction being the stronger.

  5. H-P adaptive methods for finite element analysis of aerothermal loads in high-speed flows

    NASA Technical Reports Server (NTRS)

    Chang, H. J.; Bass, J. M.; Tworzydlo, W.; Oden, J. T.

    1993-01-01

    The commitment to develop the National Aerospace Plane and Maneuvering Reentry Vehicles has generated resurgent interest in the technology required to design structures for hypersonic flight. The principal objective of this research and development effort has been to formulate and implement a new class of computational methodologies for accurately predicting fine scale phenomena associated with this class of problems. The initial focus of this effort was to develop optimal h-refinement and p-enrichment adaptive finite element methods which utilize a-posteriori estimates of the local errors to drive the adaptive methodology. Over the past year this work has specifically focused on two issues which are related to overall performance of a flow solver. These issues include the formulation and implementation (in two dimensions) of an implicit/explicit flow solver compatible with the hp-adaptive methodology, and the design and implementation of computational algorithm for automatically selecting optimal directions in which to enrich the mesh. These concepts and algorithms have been implemented in a two-dimensional finite element code and used to solve three hypersonic flow benchmark problems (Holden Mach 14.1, Edney shock on shock interaction Mach 8.03, and the viscous backstep Mach 4.08).

  6. Development and comparison of HP-41C software to predict solar irradiation of tilted surfaces, based upon cloud cover factors

    SciTech Connect

    Nawrocki, A.D.; Anderson, S.P.

    1982-01-01

    Summarized is a comparison between predicted and measured solar radiation and cloud cover data from NOAA weather stations and Solar Energy Meterological Research and Training Sites at various locations throughout the US, based upon a semiempirical method which was used recently to generate synthetic insolation data for correlation with measured solar performance under the SUEDE program. This method is unique, since it predicts irradiation of a tilted surface from sky cover estimates by weather observers, using a modified ASHRAE method to compute direct and diffuse insolation on a clear day. Data comparisons were made using an HP-41C programmable calculator, card reader, printer, and eight magnetic cards. Although a more detailed study with a larger data base is desirable, these particular findings, using hourly summations to obtain monthly averages in 1980, indicate that approximately -5 to 15% difference between measured and calculated monthly results is typical of continental US sites. A sensitivity study indicated that monthly percentage differences are reduced by centering ASHRAE constants and earth declination on the 15th day of each month instead of the 21st day.

  7. Stability of Basalt plus Anhydrite plus Calcite at HP-HT: Implications for Venus, the Earth and Mars

    NASA Technical Reports Server (NTRS)

    Martin, A. M.; Righter, K.; Treiman, A. H.

    2010-01-01

    "Canali" observed at Venus surface by Magellan are evidence for very long melt flows, but their composition and origin remain uncertain. The hypothesis of water-rich flow is not reasonable regarding the temperature at Venus surface. The length of these channels could not be explained by a silicate melt composition but more likely, by a carbonate-sulfate melt which has a much lower viscosity (Kargel et al 1994). One hypothesis is that calcite CaCO3 and anhydrite CaSO4 which are alteration products of basalts melted during meteorite impacts. A famous example recorded on the Earth (Chicxulub) produced melt and gas rich in carbon and sulfur. Calcite and sulfate evaporites are also present on Mars surface, associated with basalts. An impact on these materials might release C- and S-rich melt or fluid. Another type of planetary phenomenon (affecting only the Earth) might provoke a high pressure destabilization of basalt+anhydrite+calcite. Very high contents of C and S are measured in some Earth s magmas, either dissolved or in the form of crystals (Luhr 2008). As shown by the high H content and high fO2 of primary igneous anhydrite-bearing lavas, the high S content in their source may be explained by subduction of an anhydrite-bearing oceanic crust, either directly (by melting followed by eruption) or indirectly (by release of S-rich melt or fluid that metasomatize the mantle) . Calcite is a major product of oceanic sedimentation and alteration of the crust. Therefore, sulfate- and calcite-rich material may be subducted to high pressures and high temperatures (HP-HT) and release S- and C-rich melts or fluids which could influence the composition of subduction zone lavas or gases. Both phenomena - meteorite impact and subduction - imply HP-HT conditions - although the P-T-time paths are different. Some HP experimental/theoretical studies have been performed on basalt/eclogite, calcite and anhydrite separately or on a combination of two. In this study we performed piston

  8. Stability of basalt+anhydrite+calcite at HP-HT: implications for Venus, the Earth and Mars

    NASA Astrophysics Data System (ADS)

    Martin, A. M.; Righter, K.; Treiman, A. H.

    2010-12-01

    “Canali” observed at Venus’ surface by Magellan are evidence for very long melt flows, but their composition and origin remain uncertain. The hypothesis of water-rich flow is not reasonable regarding Venus’ surface temperature. The length of these channels could not be explained by a silicate melt composition but more likely, by a carbonate-sulfate melt which has a much lower viscosity (Kargel et al 1994). One hypothesis is that calcite CaCO3 and anhydrite CaSO4 - which are alteration products of basalts - melted during meteorite impacts. A famous example recorded on the Earth (Chicxulub) produced melt and gas rich in carbon and sulfur. Calcite and sulfate evaporites are also present on Mars surface, associated with basalts. An impact on these materials may release C- and S-rich melt or fluid. Another type of planetary phenomenon (affecting only the Earth) might provoke a high pressure destabilization of basalt+anhydrite+calcite. Very high contents of C and S are measured in some Earth’s magmas, either dissolved or in the form of crystals (Luhr 2008). As shown by the high H content and high fO2 of primary igneous anhydrite-bearing lavas, the high S content in their source may be explained by the subduction of an anhydrite-bearing oceanic crust, either directly (by melting followed by eruption) or indirectly (by release of S-rich melt or fluid that metasomatize the mantle). Calcite is a major product of oceanic sedimentation and alteration of the crust. Therefore, sulfate- and calcite-rich material may be subducted to high pressures and high temperatures (HP-HT) and release S- and C-rich melts or fluids which could influence the composition of subduction zone lavas or gases. Both phenomena - meteorite impact and subduction - imply HP-HT conditions - although the P-T-time paths are different. Some HP experimental/theoretical studies have been performed on basalt/eclogite, calcite and anhydrite separately or on a combination of two. In this study we

  9. Growth promotion in pigs by oxytetracycline coincides with down regulation of serum inflammatory parameters and of hibernation-associated protein HP-27.

    PubMed

    Soler, Laura; Miller, Ingrid; Hummel, Karin; Razzazi-Fazeli, Ebrahim; Jessen, Flemming; Escribano, Damian; Niewold, Theo

    2016-05-01

    The growth promoting effect of supplementing animal feed with antibiotics like tetracycline has traditionally been attributed to their antibiotic character. However, more evidence has been accumulated on their direct anti-inflammatory effect during the last two decades. Here we used a pig model to explore the systemic molecular effect of feed supplementation with sub therapeutic levels of oxytetracycline (OTC) by analysis of serum proteome changes. Results showed that OTC promoted growth, coinciding with a significant down regulation of different serum proteins related to inflammation, oxidation and lipid metabolism, confirming the anti-inflammatory mechanism of OTC. Interestingly, apart from the classic acute phase reactants also down regulation was seen of a hibernation associated plasma protein (HP-27), which is to our knowledge the first description in pigs. Although the exact function in non-hibernators is unclear, down regulation of HP-27 could be consistent with increased appetite, which is possibly linked to the anti-inflammatory action of OTC. Given that pigs are good models for human medicine due to their genetic and physiologic resemblance, the present results might also be used for rational intervention in human diseases in which inflammation plays an important role such as obesity, type 2 diabetes and cardiovascular diseases.

  10. BENCH-SCALE DEMONSTRATION OF HOT-GAS DESULFURIZATION TECHNOLOGY

    SciTech Connect

    1998-05-01

    The Direct Sulfur Recovery Process (DSRP) is a one- or two-stage catalytic reduction process for efficiently converting to elemental sulfur up to 98 percent or more of the sulfur dioxide (SO{sub 2}) contained in the regeneration offgas streams produced in advanced integrated gasification combined cycle (IGCC) power systems. The DSRP reacts the regeneration offgas with a small slipstream of coal gas to effect the desired reduction. In this project the DSRP was demonstrated with actual coal gas (as opposed to the simulated laboratory mixtures used in previous studies) in a 75-mm, 1-L size fixed-bed reactor. Integrated with this testing, a US Department of Energy/Research Triangle Institute (DOE/RTI) patented zinc titanate-based fluidizable sorbent formulation was tested in a 75-mm (3-in.) diameter fluidized-bed reactor, and the regeneration offgas from that test was treated with the bench-unit DSRP. The testing was conducted at the DOE Federal Energy Technology Center (FETC)-Morgantown in conjunction with test campaigns of the pilot-scale gasifier there. The test apparatus was housed in a mobile laboratory built in a specially equipped office trailer that facilitated moving the equipment from RTI in North Carolina to the West Virginia test site. A long duration test of the DSRP using actual coal gas and simulated regeneration offgas showed no degradation in efficiency of conversion to elemental sulfur after 160 h of catalyst exposure. An additional exposure (200 h) of that same catalyst charge at the General Electric pilot gasifier showed only a small decline in performance. That problem is believed to have been caused by tar and soot deposits on the catalyst, which were caused by the high tar content of the atypical fixed-bed gasifier gas. A six-fold larger, single-stage skid-mounted DSRP apparatus was fabricated for additional, larger-scale slipstream testing.

  11. Chemical formulation and combined process for inhibiting deposition and corrosion in cooling water and gypsum scaling in flue gas desulfurization scrubber systems

    SciTech Connect

    Mouche, R.J.; Lin, M.L.; Ekis, E.W. Jr.

    1989-05-30

    A combined cooling water/flue gas desulfurization process is described comprising: (a) contacting a gas with water in a cooling tower the gas having a lower temperature than the water such that upon contact the water is cooled by the transfer of thermal energy from the water to the gas. The water comprising between about 0.2 and about 100 ppm active by weight of an inhibitor formulation comprising polyacrylate, polymaleic anhydride, and phosphonate; (b) contacting a sulfur-containing gas with reagent slurry in a flue gas desulfurizer thereby desulfurizing the sulfur containing gas; and (c) supplying at least a portion of the water from the cooling tower to make up at least a portion of wash water in the desulfurizer, the water being supplied in an amount sufficient to maintain between about 0.01 and about 20 ppm active by weight of the inhibitor formulation in the reagent wash water.

  12. Appendix A: The Impact of the HP 5071A on International Atomic Time

    NASA Technical Reports Server (NTRS)

    Allan, David W.; Lepek, Alex; Cutler, Len; Giffard, Robin; Kusters, Jack

    1996-01-01

    The international clock ensemble, which contributes to the generation of International Atomic Time (TAI and UTC) has improved dramatically over the last few years. The main change has been the introduction of a significant number of HP 5071A clocks. Of the 313 clocks contributing to TAI/UTC during 1994, 94 of these were HP 5071As. The environmental insensitivity of the HP 5071A clocks is more than an order of magnitude better than that of previously contributing clocks. This environmental insensitivity translates to outstanding long-term stability - with a typical flicker floor of a few x10(sup -15). in addition, there are now several hydrogen masers with cavity tuning contributing to TAI/UTC. These not only have outstanding short-term stability, but comparatively low frequency drifts and excellent intermediate-type frequency stability. By analyzing data available from the international ensemble, we have obtained two important results. First the frequency stability obtainable with an optimum algorithm is about 10(sup -15) for both the intermediate and long-term regions. It could be as good in the short-term (if time transfer measurement instabilities were reduced sufficiently. Second, with cooperation, this performance can be made available on an international basis in near real time. The recent enhancements in the contributing clocks are already providing a significant improvement in the accuracy with which UTC is made available to the world from several of the national timing centers, such as the National Institute for Standards and Technology (NIST) and the US Naval Observatory (USNO).

  13. A GAL4-HP1 fusion protein targeted near heterochromatin promotes gene silencing.

    PubMed

    Seum, C; Spierer, A; Delattre, M; Pauli, D; Spierer, P

    2000-11-01

    We have constructed a new reporter transgene, Winkelried, equipped with a synthetic binding site for the yeast GAL4 transcriptional activator. The binding site is inserted between the white and lacZ reporter genes, and is flanked by FRT sequences. These elements allow excision of the GAL4 binding site by crossing the transgenic line with an FLP recombinase producing strain. We have generated by X-ray irradiation two independent chromosomal rearrangements, Heidi and Tell, relocating Winkelried next to pericentromeric heterochromatin. These rearrangements induce variegation of both white and lacZ. Variegation of Winkelried in the rearranged transgenic lines responds to the loss and excess of doses of the dominant suppressors of position-effect variegation (PEV) Su(var)3-7 and Su(var)2-5. Winkelried therefore constitutes a unique tool to test the effect on variegation in cis of any factor fused to the GAL4 DNA binding domain. Indeed, a chimeric protein, made of the DNA binding site of GAL4 and of HP1, the modifier of PEV encoded by Su(var)2-5, is shown to enhance variegation of Heidi and Tell. Excision of the binding sites for GAL4 in the variegating rearrangements Heidi and Tell abolishes the modifier effect of the GAL4-HP1 chimera. Therefore, in the Heidi and Tell rearrangements, enhancement of position-effect variegation depends strictly both on the concentration of GAL4-HP1 and on the presence of its binding site in the vicinity of the reporter genes.

  14. Development of an hp-version finite element method for computational optimal control

    NASA Technical Reports Server (NTRS)

    Hodges, Dewey H.; Warner, Michael S.

    1993-01-01

    The purpose of this research effort was to begin the study of the application of hp-version finite elements to the numerical solution of optimal control problems. Under NAG-939, the hybrid MACSYMA/FORTRAN code GENCODE was developed which utilized h-version finite elements to successfully approximate solutions to a wide class of optimal control problems. In that code the means for improvement of the solution was the refinement of the time-discretization mesh. With the extension to hp-version finite elements, the degrees of freedom include both nodal values and extra interior values associated with the unknown states, co-states, and controls, the number of which depends on the order of the shape functions in each element. One possible drawback is the increased computational effort within each element required in implementing hp-version finite elements. We are trying to determine whether this computational effort is sufficiently offset by the reduction in the number of time elements used and improved Newton-Raphson convergence so as to be useful in solving optimal control problems in real time. Because certain of the element interior unknowns can be eliminated at the element level by solving a small set of nonlinear algebraic equations in which the nodal values are taken as given, the scheme may turn out to be especially powerful in a parallel computing environment. A different processor could be assigned to each element. The number of processors, strictly speaking, is not required to be any larger than the number of sub-regions which are free of discontinuities of any kind.

  15. An HP Adaptive Discontinuous Galerkin Method for Hyperbolic Conservation Laws. Ph.D. Thesis

    NASA Technical Reports Server (NTRS)

    Bey, Kim S.

    1994-01-01

    This dissertation addresses various issues for model classes of hyperbolic conservation laws. The basic approach developed in this work employs a new family of adaptive, hp-version, finite element methods based on a special discontinuous Galerkin formulation for hyperbolic problems. The discontinuous Galerkin formulation admits high-order local approximations on domains of quite general geometry, while providing a natural framework for finite element approximations and for theoretical developments. The use of hp-versions of the finite element method makes possible exponentially convergent schemes with very high accuracies in certain cases; the use of adaptive hp-schemes allows h-refinement in regions of low regularity and p-enrichment to deliver high accuracy, while keeping problem sizes manageable and dramatically smaller than many conventional approaches. The use of discontinuous Galerkin methods is uncommon in applications, but the methods rest on a reasonable mathematical basis for low-order cases and has local approximation features that can be exploited to produce very efficient schemes, especially in a parallel, multiprocessor environment. The place of this work is to first and primarily focus on a model class of linear hyperbolic conservation laws for which concrete mathematical results, methodologies, error estimates, convergence criteria, and parallel adaptive strategies can be developed, and to then briefly explore some extensions to more general cases. Next, we provide preliminaries to the study and a review of some aspects of the theory of hyperbolic conservation laws. We also provide a review of relevant literature on this subject and on the numerical analysis of these types of problems.

  16. Stress corrosion evaluation of HP 9Ni-4Co-0.30C steel plate welds

    NASA Technical Reports Server (NTRS)

    Torres, Pablo D.

    1993-01-01

    A stress corrosion cracking (SCC) investigation was conducted on HP 9Ni-4Co-0.30C steel plate welds (welded by using straight polarity plasma arc and HP 9Ni-4Co-0.20C weld wire) since this material is being considered for use in the Advanced Solid Rocket Motor (ASRM) program. Prior to the welding, the material was double tempered at 538 C (1,000 F). After welding, only part of the material was stress relieved at 510 C (950 F) for 3 h. Round tensile specimens obtained from nonstress-relieved material were tested in 100-percent relative humidity at 38 C (100 F), in 3.5-percent NaCl alternate immersion, and in 5-percent salt spray at 35 C (95 F). Specimens obtained from stress-relieved material were tested in alternate immersion. The stress levels were 50, 75, and 90 percent of the corresponding 0.2-percent yield strength (YS). All the nonstress-relieved specimens exposed to salt spray and alternate immersion failed. Stress-relieved specimens (exposed to alternate immersion) failed at 75 and 90 percent of YS. No failures occurred at 50 percent of YS in the stress-relieved specimens which indicates a beneficial effect of the stress relief on the SCC resistance of these welds. The stress relief also had a positive effect on the mechanical properties of the welds (the most important being an increase of 21 percent on the YS). Under the conditions of these tests, the straight polarity plasma are welded HP 9Ni4Co-0.30C steel plate was found highly susceptible to SCC in the nonstress-relieved condition. This susceptibility to SCC was reduced by stress relieving.

  17. Hipparcos red stars in the HpVT2 and VIC systems

    NASA Astrophysics Data System (ADS)

    Platais, I.; Pourbaix, D.; Jorissen, A.; Makarov, V. V.; Berdnikov, L. N.; Samus, N. N.; Lloyd Evans, T.; Lebzelter, T.; Sperauskas, J.

    2003-01-01

    For Hipparcos M, S, and C spectral type stars, we provide calibrated instantaneous (epoch) Cousins V - I color indices using newly derived HpVT2 photometry. Three new sets of ground-based Cousins VI data have been obtained for more than 170 carbon and red M giants. These datasets in combination with the published sources of V I photometry served to obtain the calibration curves linking Hipparcos/Tycho Hp-VT2 with the Cousins V - I index. In total, 321 carbon stars and 4464 M- and S-type stars have new V - I indices. The standard error of the mean V - I is about 0.1 mag or better down to Hp~9 although it deteriorates rapidly at fainter magnitudes. These V - I indices can be used to verify the published Hipparcos V - I color indices. Thus, we have identified a handful of new cases where, instead of the real target, a random field star has been observed. A considerable fraction of the DMSA/C and DMSA/V solutions for red stars appear not to be warranted. Most likely such spurious solutions may originate from usage of a heavily biased color in the astrometric processing. Based on observations from the Hipparcos astrometric satellite operated by the European Space Agency (ESA 1997).}\\fnmsep\\thanks{Table 7 is only available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/397/997

  18. The p and h-p Versions of the Finite Element Method; State of the Art.

    DTIC Science & Technology

    1986-09-01

    INSTITUTE FOp [m]Yci C Z... S’- -_ AND TECH-INOLOGY (11111:1;) ,. Technical Note BN-1156 (0 I . % I. ,,8’ .- *.° . ’ .4’ .- o%_ THE p AND h-p VERSIONS...OF THE FINITE ELEMENT METHOD. THE STATE OF THE ART -.. ; U.S.A. %%.Z - 4’ ° DTIC .21 R U-noW _STkl;,.CT.2,1986 I. Babu~ka €’ ",’- Institute ror... Institute for Physical Science and Technology AREAS WOrK UNT NUMBERS University of Maryland College Park, MD 20742 ii. CONTROLLING OFFICE NAME AND

  19. Computational Aspects of the h, p and h-p Versions of the Finite Element Method.

    DTIC Science & Technology

    1987-03-01

    and T. Scapolla BN-1 061 March 1987 %" iqAppr,- - " . ..utr""o":" S Appr..: ’ ...... tor pilbhc j0 ,oe "IDI .. ,%~~~~1 %-... z u n Unliz~ited INSTITUTE ...PROGRAM ELEMENT. PROJECT. TASK AREA & WORK UNIT NUMIERS Institute for Physical Science and Technology University of Maryland College Park, MD 20742 it...the h, p and h-p versions of the finite element method Ivo Babulka 1" Institute for Physical Science and Technology University of Maryland, College

  20. The Theory and Practice of the h-p Version of Finite Element Method.

    DTIC Science & Technology

    1987-04-01

    85-K-0169 I. Babuska and B. Guo NSF DMS-85-16191 9. PERFORMING ORGANIZATION NAME AND ADDRES 10. PROGRAM ELEMENT. PROJECT. TASK Institute for Physical...uitered) THE THEORY AND PRACTICE O THE h-p vERSION OF FINITE ElEMENT METHOD Ben Qi Guo* Ivo Babuska** Institute of Physical Science & Technology and...1Wr-194 ’The problem with none-hmogeneous Dirichlet problem is to find the finite element solution u. £ data was studied by Babuika, Guo.im- 4401 The h